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Sample records for 3d global hybrid

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

    NASA Technical Reports Server (NTRS)

    Lipatov, Alexander S.; Combi, Michael R.

    2006-01-01

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

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

    NASA Technical Reports Server (NTRS)

    Lipatov, Alexander S.; Combi, Michael R.

    2004-01-01

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

  3. Global effects of transmitted shock wave propagation through the Earth's inner magnetosphere: First results from 3-D hybrid kinetic modeling

    NASA Astrophysics Data System (ADS)

    Lipatov, A. S.; Sibeck, D. G.

    2016-09-01

    We use a new hybrid kinetic model to simulate the response of ring current, outer radiation belt, and plasmaspheric particle populations to impulsive interplanetary shocks. Since particle distributions attending the interplanetary shock waves and in the ring current and radiation belts are non-Maxwellian, wave-particle interactions play a crucial role in energy transport within the inner magnetosphere. Finite gyroradius effects become important in mass loading the shock waves with the background plasma in the presence of higher energy ring current and radiation belt ions and electrons. Initial results show that shocks cause strong deformations in the global structure of the ring current, radiation belt, and plasmasphere. The ion velocity distribution functions at the shock front, in the ring current, and in the radiation belt help us determine energy transport through the Earth's inner magnetosphere.

  4. Global Effects of Transmitted Shock Wave Propagation Through the Earth's Inner Magnetosphere: First Results from 3-D Hybrid Kinetic Modeling

    NASA Technical Reports Server (NTRS)

    Lipatov, A. S.; Sibeck, D. G.

    2016-01-01

    We use a new hybrid kinetic model to simulate the response of ring current, outer radiation belt, and plasmaspheric particle populations to impulsive interplanetary shocks. Since particle distributions attending the interplanetary shock waves and in the ring current and radiation belts are non-Maxwellian, waveparticle interactions play a crucial role in energy transport within the inner magnetosphere. Finite gyroradius effects become important in mass loading the shock waves with the background plasma in the presence of higher energy ring current and radiation belt ions and electrons. Initial results show that shocks cause strong deformations in the global structure of the ring current, radiation belt, and plasmasphere. The ion velocity distribution functions at the shock front, in the ring current, and in the radiation belt help us determine energy transport through the Earth's inner magnetosphere.

  5. A Hybrid 3D Indoor Space Model

    NASA Astrophysics Data System (ADS)

    Jamali, Ali; Rahman, Alias Abdul; Boguslawski, Pawel

    2016-10-01

    GIS integrates spatial information and spatial analysis. An important example of such integration is for emergency response which requires route planning inside and outside of a building. Route planning requires detailed information related to indoor and outdoor environment. Indoor navigation network models including Geometric Network Model (GNM), Navigable Space Model, sub-division model and regular-grid model lack indoor data sources and abstraction methods. In this paper, a hybrid indoor space model is proposed. In the proposed method, 3D modeling of indoor navigation network is based on surveying control points and it is less dependent on the 3D geometrical building model. This research proposes a method of indoor space modeling for the buildings which do not have proper 2D/3D geometrical models or they lack semantic or topological information. The proposed hybrid model consists of topological, geometrical and semantical space.

  6. Improved hybrid optimization algorithm for 3D protein structure prediction.

    PubMed

    Zhou, Changjun; Hou, Caixia; Wei, Xiaopeng; Zhang, Qiang

    2014-07-01

    A new improved hybrid optimization algorithm - PGATS algorithm, which is based on toy off-lattice model, is presented for dealing with three-dimensional protein structure prediction problems. The algorithm combines the particle swarm optimization (PSO), genetic algorithm (GA), and tabu search (TS) algorithms. Otherwise, we also take some different improved strategies. The factor of stochastic disturbance is joined in the particle swarm optimization to improve the search ability; the operations of crossover and mutation that are in the genetic algorithm are changed to a kind of random liner method; at last tabu search algorithm is improved by appending a mutation operator. Through the combination of a variety of strategies and algorithms, the protein structure prediction (PSP) in a 3D off-lattice model is achieved. The PSP problem is an NP-hard problem, but the problem can be attributed to a global optimization problem of multi-extremum and multi-parameters. This is the theoretical principle of the hybrid optimization algorithm that is proposed in this paper. The algorithm combines local search and global search, which overcomes the shortcoming of a single algorithm, giving full play to the advantage of each algorithm. In the current universal standard sequences, Fibonacci sequences and real protein sequences are certified. Experiments show that the proposed new method outperforms single algorithms on the accuracy of calculating the protein sequence energy value, which is proved to be an effective way to predict the structure of proteins.

  7. Global Magnetospheric Modeling of 3D Reconnection

    NASA Technical Reports Server (NTRS)

    Spicer, Daniel S.

    1999-01-01

    A review of approaches to the global modeling of the terrestrial magnetosphere, how these approaches are utilized to interpret satellite data, and how these approaches have been successful at predicting magnetospheric phenomena will be presented. In addition, the importance of the ionospheric boundary and its effect on the globally topology of the magnetospheric magnetic field will be reviewed. In particular, numerical results that are rapidly changing our view of magnetospheric reconnection within the magnetospheric magnetic field will be discussed.

  8. Hybrid 3D-2D printing for bone scaffolds fabrication

    NASA Astrophysics Data System (ADS)

    Seleznev, V. A.; Prinz, V. Ya

    2017-02-01

    It is a well-known fact that bone scaffold topography on micro- and nanometer scale influences the cellular behavior. Nano-scale surface modification of scaffolds allows the modulation of biological activity for enhanced cell differentiation. To date, there has been only a limited success in printing scaffolds with micro- and nano-scale features exposed on the surface. To improve on the currently available imperfect technologies, in our paper we introduce new hybrid technologies based on a combination of 2D (nano imprint) and 3D printing methods. The first method is based on using light projection 3D printing and simultaneous 2D nanostructuring of each of the layers during the formation of the 3D structure. The second method is based on the sequential integration of preliminarily created 2D nanostructured films into a 3D printed structure. The capabilities of the developed hybrid technologies are demonstrated with the example of forming 3D bone scaffolds. The proposed technologies can be used to fabricate complex 3D micro- and nanostructured products for various fields.

  9. Hybrid 3D-2D printing of bone scaffolds Hybrid 3D-2D printing methods for bone scaffolds fabrication.

    PubMed

    Prinz, V Ya; Seleznev, Vladimir

    2016-12-13

    It is a well-known fact that bone scaffold topography on micro- and nanometer scale influences the cellular behavior. Nano-scale surface modification of scaffolds allows the modulation of biological activity for enhanced cell differentiation. To date, there has been only a limited success in printing scaffolds with micro- and nano-scale features exposed on the surface. To improve on the currently available imperfect technologies, in our paper we introduce new hybrid technologies based on a combination of 2D (nano imprint) and 3D printing methods. The first method is based on using light projection 3D printing and simultaneous 2D nanostructuring of each of the layers during the formation of the 3D structure. The second method is based on the sequential integration of preliminarily created 2D nanostructured films into a 3D printed structure. The capabilities of the developed hybrid technologies are demonstrated with the example of forming 3D bone scaffolds. The proposed technologies can be used to fabricate complex 3D micro- and nanostructured products for various fields.

  10. A hybrid framework for 3D medical image segmentation.

    PubMed

    Chen, Ting; Metaxas, Dimitris

    2005-12-01

    In this paper we propose a novel hybrid 3D segmentation framework which combines Gibbs models, marching cubes and deformable models. In the framework, first we construct a new Gibbs model whose energy function is defined on a high order clique system. The new model includes both region and boundary information during segmentation. Next we improve the original marching cubes method to construct 3D meshes from Gibbs models' output. The 3D mesh serves as the initial geometry of the deformable model. Then we deform the deformable model using external image forces so that the model converges to the object surface. We run the Gibbs model and the deformable model recursively by updating the Gibbs model's parameters using the region and boundary information in the deformable model segmentation result. In our approach, the hybrid combination of region-based methods and boundary-based methods results in improved segmentations of complex structures. The benefit of the methodology is that it produces high quality segmentations of 3D structures using little prior information and minimal user intervention. The modules in this segmentation methodology are developed within the context of the Insight ToolKit (ITK). We present experimental segmentation results of brain tumors and evaluate our method by comparing experimental results with expert manual segmentations. The evaluation results show that the methodology achieves high quality segmentation results with computational efficiency. We also present segmentation results of other clinical objects to illustrate the strength of the methodology as a generic segmentation framework.

  11. Hybrid additive manufacturing of 3D electronic systems

    NASA Astrophysics Data System (ADS)

    Li, J.; Wasley, T.; Nguyen, T. T.; Ta, V. D.; Shephard, J. D.; Stringer, J.; Smith, P.; Esenturk, E.; Connaughton, C.; Kay, R.

    2016-10-01

    A novel hybrid additive manufacturing (AM) technology combining digital light projection (DLP) stereolithography (SL) with 3D micro-dispensing alongside conventional surface mount packaging is presented in this work. This technology overcomes the inherent limitations of individual AM processes and integrates seamlessly with conventional packaging processes to enable the deposition of multiple materials. This facilitates the creation of bespoke end-use products with complex 3D geometry and multi-layer embedded electronic systems. Through a combination of four-point probe measurement and non-contact focus variation microscopy, it was identified that there was no obvious adverse effect of DLP SL embedding process on the electrical conductivity of printed conductors. The resistivity maintained to be less than 4  ×  10-4 Ω · cm before and after DLP SL embedding when cured at 100 °C for 1 h. The mechanical strength of SL specimens with thick polymerized layers was also identified through tensile testing. It was found that the polymerization thickness should be minimised (less than 2 mm) to maximise the bonding strength. As a demonstrator a polymer pyramid with embedded triple-layer 555 LED blinking circuitry was successfully fabricated to prove the technical viability.

  12. Magnetism in a graphene-4 f -3 d hybrid system

    NASA Astrophysics Data System (ADS)

    Huttmann, Felix; Klar, David; Atodiresei, Nicolae; Schmitz-Antoniak, Carolin; Smekhova, Alevtina; Martínez-Galera, Antonio J.; Caciuc, Vasile; Bihlmayer, Gustav; Blügel, Stefan; Michely, Thomas; Wende, Heiko

    2017-02-01

    We create an interface of graphene with a metallic and magnetic support that leaves its electronic structure largely intact. This is achieved by exposing epitaxial graphene on ferromagnetic thin films of Co and Ni to vapor of the rare earth metal Eu at elevated temperatures, resulting in the intercalation of an Eu monolayer in between graphene and its substrate. The system is atomically well defined, with the Eu monolayer forming a (√{3 }×√{3 }) R 30∘ superstructure with respect to the graphene lattice. Thereby, we avoid the strong hybridization with the (Ni,Co) substrate 3 d states that otherwise drastically modify the electronic structure of graphene. This picture is suggested by our x-ray absorption spectroscopy measurements which show that after Eu intercalation the empty 2 p states of C atoms resemble more the ones measured for graphite in contrast to graphene directly bound to 3 d ferromagnetic substrates. We use x-ray magnetic circular dichroism at the Co and Ni L2 ,3 and Eu M4 ,5 as an element-specific probe to investigate magnetism in these systems. An antiferromagnetic coupling between Eu and Co/Ni moments is found, which is so strong that a magnetic moment of the Eu layer can be detected at room temperature. Density functional theory calculations confirm the antiferromagnetic coupling and provide an atomic insight into the magnetic coupling mechanism.

  13. Efficient global wave propagation adapted to 3-D structural complexity: a pseudospectral/spectral-element approach

    NASA Astrophysics Data System (ADS)

    Leng, Kuangdai; Nissen-Meyer, Tarje; van Driel, Martin

    2016-12-01

    We present a new, computationally efficient numerical method to simulate global seismic wave propagation in realistic 3-D Earth models. We characterize the azimuthal dependence of 3-D wavefields in terms of Fourier series, such that the 3-D equations of motion reduce to an algebraic system of coupled 2-D meridian equations, which is then solved by a 2-D spectral element method (SEM). Computational efficiency of such a hybrid method stems from lateral smoothness of 3-D Earth models and axial singularity of seismic point sources, which jointly confine the Fourier modes of wavefields to a few lower orders. We show novel benchmarks for global wave solutions in 3-D structures between our method and an independent, fully discretized 3-D SEM with remarkable agreement. Performance comparisons are carried out on three state-of-the-art tomography models, with seismic period ranging from 34 s down to 11 s. It turns out that our method has run up to two orders of magnitude faster than the 3-D SEM, featured by a computational advantage expanding with seismic frequency.

  14. GBS: Global 3D simulation of tokamak edge region

    NASA Astrophysics Data System (ADS)

    Zhu, Ben; Fisher, Dustin; Rogers, Barrett; Ricci, Paolo

    2012-10-01

    A 3D two-fluid global code, namely Global Braginskii Solver (GBS), is being developed to explore the physics of turbulent transport, confinement, self-consistent profile formation, pedestal scaling and related phenomena in the edge region of tokamaks. Aimed at solving drift-reduced Braginskii equations [1] in complex magnetic geometry, the GBS is used for turbulence simulation in SOL region. In the recent upgrade, the simulation domain is expanded into close flux region with twist-shift boundary conditions. Hence, the new GBS code is able to explore global transport physics in an annular full-torus domain from the top of the pedestal into the far SOL. We are in the process of identifying and analyzing the linear and nonlinear instabilities in the system using the new GBS code. Preliminary results will be presented and compared with other codes if possible.[4pt] [1] A. Zeiler, J. F. Drake and B. Rogers, Phys. Plasmas 4, 2134 (1997)

  15. Enhanced hybrid search algorithm for protein structure prediction using the 3D-HP lattice model.

    PubMed

    Zhou, Changjun; Hou, Caixia; Zhang, Qiang; Wei, Xiaopeng

    2013-09-01

    The problem of protein structure prediction in the hydrophobic-polar (HP) lattice model is the prediction of protein tertiary structure. This problem is usually referred to as the protein folding problem. This paper presents a method for the application of an enhanced hybrid search algorithm to the problem of protein folding prediction, using the three dimensional (3D) HP lattice model. The enhanced hybrid search algorithm is a combination of the particle swarm optimizer (PSO) and tabu search (TS) algorithms. Since the PSO algorithm entraps local minimum in later evolution extremely easily, we combined PSO with the TS algorithm, which has properties of global optimization. Since the technologies of crossover and mutation are applied many times to PSO and TS algorithms, so enhanced hybrid search algorithm is called the MCMPSO-TS (multiple crossover and mutation PSO-TS) algorithm. Experimental results show that the MCMPSO-TS algorithm can find the best solutions so far for the listed benchmarks, which will help comparison with any future paper approach. Moreover, real protein sequences and Fibonacci sequences are verified in the 3D HP lattice model for the first time. Compared with the previous evolutionary algorithms, the new hybrid search algorithm is novel, and can be used effectively to predict 3D protein folding structure. With continuous development and changes in amino acids sequences, the new algorithm will also make a contribution to the study of new protein sequences.

  16. Impact of 3D Var GSI-ENKF hybrid data assimilation system

    NASA Astrophysics Data System (ADS)

    Prasad, V. S.; Johny, C. J.; Sodhi, Jagdeep Singh

    2016-12-01

    The hybrid two-way coupled 3DEnsVar assimilation system was tested with the NCMRWF global data assimilation forecasting system. At present, this system consists of T574L64 deterministic model and the grid-point statistical interpolation analysis scheme. In this experiment, the analysis system is modified with a two-way coupling with an 80 member Ensemble Kalman Filter of T254L64 resolution and runs are carried out in parallel to the operational system for the Indian summer monsoon season (June-September) for the year 2015 to study its impact. Both the assimilation systems are based on NCEP GFS system. It is found that hybrid assimilation marginally improved the quality of the forecasts of all variables over the deterministic 3D Var system, in terms of statistical skill scores and also in terms of circulation features. The impact of the hybrid system in prediction of extreme rainfall and cyclone track is discussed.

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

    NASA Astrophysics Data System (ADS)

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

    2013-09-01

    to LoD4. The accuracy and structural complexity of the 3D objects increases with the LoD level where LoD0 is the simplest LoD (2.5D; Digital Terrain Model (DTM) + building or roof print) while LoD4 is the most complex LoD (architectural details with interior structures). Semantic information is one of the main components in CityGML and 3D City Models, and provides important information for any analyses. However, more often than not, the semantic information is not available for the 3D city model due to the unstandardized modelling process. One of the examples is where a building is normally generated as one object (without specific feature layers such as Roof, Ground floor, Level 1, Level 2, Block A, Block B, etc). This research attempts to develop a method to improve the semantic data updating process by segmenting the 3D building into simpler parts which will make it easier for the users to select and update the semantic information. The methodology is implemented for 3D buildings in LoD2 where the buildings are generated without architectural details but with distinct roof structures. This paper also introduces hybrid semantic-geometric 3D segmentation method that deals with hierarchical segmentation of a 3D building based on its semantic value and surface characteristics, fitted by one of the predefined primitives. For future work, the segmentation method will be implemented as part of the change detection module that can detect any changes on the 3D buildings, store and retrieve semantic information of the changed structure, automatically updates the 3D models and visualize the results in a userfriendly graphical user interface (GUI).

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

    NASA Astrophysics Data System (ADS)

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

    2005-12-01

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

  19. 3-D Hybrid Simulation of Quasi-Parallel Bow Shock and Its Effects on the Magnetosphere

    SciTech Connect

    Lin, Y.; Wang, X.Y.

    2005-08-01

    A three-dimensional (3-D) global-scale hybrid simulation is carried out for the structure of the quasi-parallel bow shock, in particular the foreshock waves and pressure pulses. The wave evolution and interaction with the dayside magnetosphere are discussed. It is shown that diamagnetic cavities are generated in the turbulent foreshock due to the ion beam plasma interaction, and these compressional pulses lead to strong surface perturbations at the magnetopause and Alfven waves/field line resonance in the magnetosphere.

  20. Mars Odyssey Seen by Mars Global Surveyor (3-D)

    NASA Technical Reports Server (NTRS)

    2005-01-01

    This stereoscopic picture of NASA's Mars Odyssey spacecraft was created from two views of that spacecraft taken by the Mars Orbiter Camera on NASA's Mars Global Surveyor. The camera's successful imaging of Odyssey and of the European Space Agency's Mars Express in April 2005 produced the first pictures of any spacecraft orbiting Mars taken by another spacecraft orbiting Mars.

    Mars Global Surveyor acquired this image of Mars Odyssey on April 21, 2005. The stereoscopic picture combines one view captured while the two orbiters were 90 kilometers (56 miles) apart with a second view captured from a slightly different angle when the two orbiters were 135 kilometers (84 miles) apart. For proper viewing, the user needs '3-D' glasses with red over the left eye and blue over the right eye.

    The Mars Orbiter Camera can resolve features on the surface of Mars as small as a few meters or yards across from Mars Global Surveyor's orbital altitude of 350 to 405 kilometers (217 to 252 miles). From a distance of 100 kilometers (62 miles), the camera would be able to resolve features substantially smaller than 1 meter or yard across.

    Mars Odyssey was launched on April 7, 2001, and reached Mars on Oct. 24, 2001. Mars Global Surveyor left Earth on Nov. 7, 1996, and arrived in Mars orbit on Sept. 12, 1997. Both orbiters are in an extended mission phase, both have relayed data from the Mars Exploration Rovers, and both are continuing to return exciting new results from Mars. JPL, a division of the California Institute of Technology, Pasadena, manages both missions for NASA's Science Mission Directorate, Washington, D.C.

  1. Hybrid 3D printing: a game-changer in personalized cardiac medicine?

    PubMed

    Kurup, Harikrishnan K N; Samuel, Bennett P; Vettukattil, Joseph J

    2015-12-01

    Three-dimensional (3D) printing in congenital heart disease has the potential to increase procedural efficiency and patient safety by improving interventional and surgical planning and reducing radiation exposure. Cardiac magnetic resonance imaging and computed tomography are usually the source datasets to derive 3D printing. More recently, 3D echocardiography has been demonstrated to derive 3D-printed models. The integration of multiple imaging modalities for hybrid 3D printing has also been shown to create accurate printed heart models, which may prove to be beneficial for interventional cardiologists, cardiothoracic surgeons, and as an educational tool. Further advancements in the integration of different imaging modalities into a single platform for hybrid 3D printing and virtual 3D models will drive the future of personalized cardiac medicine.

  2. 3D Evolution of Lower Hybrid Turbulence in the Ionosphere

    NASA Astrophysics Data System (ADS)

    Ganguli, Gurudas; Crabtree, Chris; Rudakov, Leonid

    2016-10-01

    Three-dimensional evolution of the lower hybrid turbulence driven by a spatially localized ion ring beam perpendicular to the ambient magnetic field in space plasmas is considered. It is shown that the quasi-linear saturation model breaks down when the nonlinear rate of scattering by thermal electron is larger than linear damping rates, which can occur even for low wave amplitudes. The evolution is found to be essentially a three-dimensional phenomenon, which cannot be accurately explained by two-dimensional simulations. An important feature missed in previous studies of this phenomenon is the nonlinear conversion of electrostatic lower hybrid waves into electromagnetic whistler and magnetosonic waves and the consequent energy loss due to radiation from the source region that can result in unique low-amplitude saturation with extended saturation time. It is shown that when the realistic nonlinear effects are considered the net energy that can be permanently extracted from the ring beam is larger. The results are applied to anticipate the outcome of a planned experiment that will seed lower hybrid turbulence in the ionosphere and monitor its evolution. NRL Base Program.

  3. Fluorescence in situ hybridization applications for super-resolution 3D structured illumination microscopy.

    PubMed

    Markaki, Yolanda; Smeets, Daniel; Cremer, Marion; Schermelleh, Lothar

    2013-01-01

    Fluorescence in situ hybridization on three-dimensionally preserved cells (3D-FISH) is an efficient tool to analyze the subcellular localization and spatial arrangement of targeted DNA sequences and RNA transcripts at the single cell level. 3D reconstructions from serial optical sections obtained by confocal laser scanning microscopy (CLSM) have long been considered the gold standard for 3D-FISH analyses. Recent super-resolution techniques circumvent the diffraction-limit of optical resolution and have defined a new state-of-the-art in bioimaging. Three-dimensional structured illumination microscopy (3D-SIM) represents one of these technologies. Notably, 3D-SIM renders an eightfold improved volumetric resolution over conventional imaging, and allows the simultaneous visualization of differently labeled target structures. These features make this approach highly attractive for the analysis of spatial relations and substructures of nuclear targets that escape detection by conventional light microscopy. Here, we focus on the application of 3D-SIM for the visualization of subnuclear 3D-FISH preparations. In comparison with conventional fluorescence microscopy, the quality of 3D-SIM data is dependent to a much greater extent on the optimal sample preparation, labeling and acquisition conditions. We describe typical problems encountered with super-resolution imaging of in situ hybridizations in mammalian tissue culture cells and provide optimized DNA-/(RNA)-FISH protocols including combinations with immunofluorescence staining (Immuno-FISH) and DNA replication labeling using click chemistry.

  4. Mobile 3D quality of experience evaluation: a hybrid data collection and analysis approach

    NASA Astrophysics Data System (ADS)

    Utriainen, Timo; Häyrynen, Jyrki; Jumisko-Pyykkö, Satu; Boev, Atanas; Gotchev, Atanas; Hannuksela, Miska M.

    2011-02-01

    The paper presents a hybrid approach to study the user's experienced quality of 3D visual content on mobile autostereoscopic displays. It combines extensive subjective tests with collection and objective analysis of eye-tracked data. 3D cues which are significant for mobiles are simulated in the generated 3D test content. The methodology for conducting subjective quality evaluation includes hybrid data-collection of quantitative quality preferences, qualitative impressions, and binocular eye-tracking. We present early results of the subjective tests along with eye movement reaction times, areas of interest and heatmaps obtained from raw eye-tracked data after statistical analysis. The study contributes to the question what is important to be visualized on portable auto-stereoscopic displays and how to maintain and visually enhance the quality of 3D content for such displays.

  5. Improved time-space method for 3-D heat transfer problems including global warming

    SciTech Connect

    Saitoh, T.S.; Wakashima, Shinichiro

    1999-07-01

    In this paper, the Time-Space Method (TSM) which has been proposed for solving general heat transfer and fluid flow problems was improved in order to cover global and urban warming. The TSM is effective in almost all-transient heat transfer and fluid flow problems, and has been already applied to the 2-D melting problems (or moving boundary problems). The computer running time will be reduced to only 1/100th--1/1000th of the existing schemes for 2-D and 3-D problems. However, in order to apply to much larger-scale problems, for example, global warming, urban warming and general ocean circulation, the SOR method (or other iterative methods) in four dimensions is somewhat tedious and provokingly slow. Motivated by the above situation, the authors improved the speed of iteration of the previous TSM by introducing the following ideas: (1) Timewise chopping: Time domain is chopped into small peaches to save memory requirement; (2) Adaptive iteration: Converged region is eliminated for further iteration; (3) Internal selective iteration: Equation with slow iteration speed in iterative procedure is selectively iterated to accelerate entire convergence; and (4) False transient integration: False transient term is added to the Poisson-type equation and the relevant solution is regarded as a parabolic equation. By adopting the above improvements, the higher-order finite different schemes and the hybrid mesh, the computer running time for the TSM is reduced to some 1/4600th of the conventional explicit method for a typical 3-D natural convection problem in a closed cavity. The proposed TSM will be more efficacious for large-scale environmental problems, such as global warming, urban warming and general ocean circulation, in which a tremendous computing time would be required.

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

    NASA Astrophysics Data System (ADS)

    Masson, Yder; Romanowicz, Barbara

    2013-04-01

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

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

    PubMed

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

    2015-04-07

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

  8. A multiply-add engine with monolithically integrated 3D memristor crossbar/CMOS hybrid circuit.

    PubMed

    Chakrabarti, B; Lastras-Montaño, M A; Adam, G; Prezioso, M; Hoskins, B; Cheng, K-T; Strukov, D B

    2017-02-14

    Silicon (Si) based complementary metal-oxide semiconductor (CMOS) technology has been the driving force of the information-technology revolution. However, scaling of CMOS technology as per Moore's law has reached a serious bottleneck. Among the emerging technologies memristive devices can be promising for both memory as well as computing applications. Hybrid CMOS/memristor circuits with CMOL (CMOS + "Molecular") architecture have been proposed to combine the extremely high density of the memristive devices with the robustness of CMOS technology, leading to terabit-scale memory and extremely efficient computing paradigm. In this work, we demonstrate a hybrid 3D CMOL circuit with 2 layers of memristive crossbars monolithically integrated on a pre-fabricated CMOS substrate. The integrated crossbars can be fully operated through the underlying CMOS circuitry. The memristive devices in both layers exhibit analog switching behavior with controlled tunability and stable multi-level operation. We perform dot-product operations with the 2D and 3D memristive crossbars to demonstrate the applicability of such 3D CMOL hybrid circuits as a multiply-add engine. To the best of our knowledge this is the first demonstration of a functional 3D CMOL hybrid circuit.

  9. A multiply-add engine with monolithically integrated 3D memristor crossbar/CMOS hybrid circuit

    NASA Astrophysics Data System (ADS)

    Chakrabarti, B.; Lastras-Montaño, M. A.; Adam, G.; Prezioso, M.; Hoskins, B.; Cheng, K.-T.; Strukov, D. B.

    2017-02-01

    Silicon (Si) based complementary metal-oxide semiconductor (CMOS) technology has been the driving force of the information-technology revolution. However, scaling of CMOS technology as per Moore’s law has reached a serious bottleneck. Among the emerging technologies memristive devices can be promising for both memory as well as computing applications. Hybrid CMOS/memristor circuits with CMOL (CMOS + “Molecular”) architecture have been proposed to combine the extremely high density of the memristive devices with the robustness of CMOS technology, leading to terabit-scale memory and extremely efficient computing paradigm. In this work, we demonstrate a hybrid 3D CMOL circuit with 2 layers of memristive crossbars monolithically integrated on a pre-fabricated CMOS substrate. The integrated crossbars can be fully operated through the underlying CMOS circuitry. The memristive devices in both layers exhibit analog switching behavior with controlled tunability and stable multi-level operation. We perform dot-product operations with the 2D and 3D memristive crossbars to demonstrate the applicability of such 3D CMOL hybrid circuits as a multiply-add engine. To the best of our knowledge this is the first demonstration of a functional 3D CMOL hybrid circuit.

  10. A multiply-add engine with monolithically integrated 3D memristor crossbar/CMOS hybrid circuit

    PubMed Central

    Chakrabarti, B.; Lastras-Montaño, M. A.; Adam, G.; Prezioso, M.; Hoskins, B.; Cheng, K.-T.; Strukov, D. B.

    2017-01-01

    Silicon (Si) based complementary metal-oxide semiconductor (CMOS) technology has been the driving force of the information-technology revolution. However, scaling of CMOS technology as per Moore’s law has reached a serious bottleneck. Among the emerging technologies memristive devices can be promising for both memory as well as computing applications. Hybrid CMOS/memristor circuits with CMOL (CMOS + “Molecular”) architecture have been proposed to combine the extremely high density of the memristive devices with the robustness of CMOS technology, leading to terabit-scale memory and extremely efficient computing paradigm. In this work, we demonstrate a hybrid 3D CMOL circuit with 2 layers of memristive crossbars monolithically integrated on a pre-fabricated CMOS substrate. The integrated crossbars can be fully operated through the underlying CMOS circuitry. The memristive devices in both layers exhibit analog switching behavior with controlled tunability and stable multi-level operation. We perform dot-product operations with the 2D and 3D memristive crossbars to demonstrate the applicability of such 3D CMOL hybrid circuits as a multiply-add engine. To the best of our knowledge this is the first demonstration of a functional 3D CMOL hybrid circuit. PMID:28195239

  11. A hybrid approach for addressing ring flexibility in 3D database searching.

    PubMed

    Sadowski, J

    1997-01-01

    A hybrid approach for flexible 3D database searching is presented that addresses the problem of ring flexibility. It combines the explicit storage of up to 25 multiple conformations of rings, with up to eight atoms, generated by the 3D structure generator CORINA with the power of a torsional fitting technique implemented in the 3D database system UNITY. A comparison with the original UNITY approach, using a database with about 130,000 entries and five different pharmacophore queries, was performed. The hybrid approach scored, on an average, 10-20% more hits than the reference run. Moreover, specific problems with unrealistic hit geometries produced by the original approach can be excluded. In addition, the influence of the maximum number of ring conformations per molecule was investigated. An optimal number of 10 conformations per molecule is recommended.

  12. Recent US Activities Toward Development of a Global Tropospheric 3D Wind Profiling System

    NASA Astrophysics Data System (ADS)

    Gentry, B. M.; Atlas, R.; Baker, W.; Emmitt, G. D.; Hardesty, R. M.; Kakar, R. K.; Kavaya, M. J.; Mango, S.; Miller, K.; Riishojgaard, L. P.

    2008-12-01

    The wind field plays a unique dynamical role in forcing the mass field to adjust to it at all scales in the tropics, and at small scales in the extra-tropics. Because of this unique role, knowledge of the wind field is required to accurately specify the global initial conditions for numerical weather forecasting. In addition to improving numerical weather prediction, there is also a need for improved accuracy of wind fields to assess long term sensitivity of the general circulation to climate change and to improve horizontal and vertical transport estimates of important atmospheric constituents. In spite of the significance, the 3-D structure of the wind field remains largely unobserved on a global scale. A new satellite mission to accurately measure the global wind field would fill this important gap in the Global Observing System. Space-based Doppler wind lidar has been identified as the key technology necessary to meet the global wind profiling requirement. The 2007 NRC Decadal Survey for Earth Science lists a Global Tropospheric 3-D Wind mission as one of the 15 priority missions recommended for NASA in the next decade. The NRC survey recommended a two phase approach to achieving an operational global wind measurement capability. The first recommended step is for NASA to develop the technology and fly a pre-operational mission to demonstrate the technology and measurement concept and establish the performance standards for an operational wind mission. Phase two would be to develop and fly an operational wind system in the 2025 timeframe. The technology approach recommended is a hybrid Doppler wind lidar (HDWL). The HDWL takes advantage of the complementary capabilities of two Doppler lidar technologies, a coherent Doppler lidar sensing winds from the aerosol backscattered laser signal at a wavelength of 2 microns and a direct detection Doppler lidar sensing winds from the molecular backscattered laser signal at 355 nm. The direct detection Doppler system

  13. Development of hybrid 3-D hydrological modeling for the NCAR Community Earth System Model (CESM)

    SciTech Connect

    Zeng, Xubin; Troch, Peter; Pelletier, Jon; Niu, Guo-Yue; Gochis, David

    2015-11-15

    This is the Final Report of our four-year (3-year plus one-year no cost extension) collaborative project between the University of Arizona (UA) and the National Center for Atmospheric Research (NCAR). The overall objective of our project is to develop and evaluate the first hybrid 3-D hydrological model with a horizontal grid spacing of 1 km for the NCAR Community Earth System Model (CESM). We have made substantial progress in model development and evaluation, computational efficiencies and software engineering, and data development and evaluation, as discussed in Sections 2-4. Section 5 presents our success in data dissemination, while Section 6 discusses the scientific impacts of our work. Section 7 discusses education and mentoring success of our project, while Section 8 lists our relevant DOE services. All peer-reviewed papers that acknowledged this project are listed in Section 9. Highlights of our achievements include: • We have finished 20 papers (most published already) on model development and evaluation, computational efficiencies and software engineering, and data development and evaluation • The global datasets developed under this project have been permanently archived and publicly available • Some of our research results have already been implemented in WRF and CLM • Patrick Broxton and Michael Brunke have received their Ph.D. • PI Zeng has served on DOE proposal review panels and DOE lab scientific focus area (SFA) review panels

  14. Hybrid atlas-based and image-based approach for segmenting 3D brain MRIs

    NASA Astrophysics Data System (ADS)

    Bueno, Gloria; Musse, Olivier; Heitz, Fabrice; Armspach, Jean-Paul

    2001-07-01

    This work is a contribution to the problem of localizing key cerebral structures in 3D MRIs and its quantitative evaluation. In pursuing it, the cooperation between an image-based segmentation method and a hierarchical deformable registration approach has been considered. The segmentation relies on two main processes: homotopy modification and contour decision. The first one is achieved by a marker extraction stage where homogeneous 3D regions of an image, I(s), from the data set are identified. These regions, M(I), are obtained combining information from deformable atlas, achieved by the warping of eight previous labeled maps on I(s). Then, the goal of the decision stage is to precisely locate the contours of the 3D regions set by the markers. This contour decision is performed by a 3D extension of the watershed transform. The anatomical structures taken into consideration and embedded into the atlas are brain, ventricles, corpus callosum, cerebellum, right and left hippocampus, medulla and midbrain. The hybrid method operates fully automatically and in 3D, successfully providing segmented brain structures. The quality of the segmentation has been studied in terms of the detected volume ratio by using kappa statistic and ROC analysis. Results of the method are shown and validated on a 3D MRI phantom. This study forms part of an on-going long term research aiming at the creation of a 3D probabilistic multi-purpose anatomical brain atlas.

  15. 2D-3D hybrid stabilized finite element method for tsunami runup simulations

    NASA Astrophysics Data System (ADS)

    Takase, S.; Moriguchi, S.; Terada, K.; Kato, J.; Kyoya, T.; Kashiyama, K.; Kotani, T.

    2016-09-01

    This paper presents a two-dimensional (2D)-three-dimensional (3D) hybrid stabilized finite element method that enables us to predict a propagation process of tsunami generated in a hypocentral region, which ranges from offshore propagation to runup to urban areas, with high accuracy and relatively low computational costs. To be more specific, the 2D shallow water equation is employed to simulate the propagation of offshore waves, while the 3D Navier-Stokes equation is employed for the runup in urban areas. The stabilized finite element method is utilized for numerical simulations for both of the 2D and 3D domains that are independently discretized with unstructured meshes. The multi-point constraint and transmission methods are applied to satisfy the continuity of flow velocities and pressures at the interface between the resulting 2D and 3D meshes, since neither their spatial dimensions nor node arrangements are consistent. Numerical examples are presented to demonstrate the performance of the proposed hybrid method to simulate tsunami behavior, including offshore propagation and runup to urban areas, with substantially lower computation costs in comparison with full 3D computations.

  16. R3D Align web server for global nucleotide to nucleotide alignments of RNA 3D structures

    PubMed Central

    Rahrig, Ryan R.; Petrov, Anton I.; Leontis, Neocles B.; Zirbel, Craig L.

    2013-01-01

    The R3D Align web server provides online access to ‘RNA 3D Align’ (R3D Align), a method for producing accurate nucleotide-level structural alignments of RNA 3D structures. The web server provides a streamlined and intuitive interface, input data validation and output that is more extensive and easier to read and interpret than related servers. The R3D Align web server offers a unique Gallery of Featured Alignments, providing immediate access to pre-computed alignments of large RNA 3D structures, including all ribosomal RNAs, as well as guidance on effective use of the server and interpretation of the output. By accessing the non-redundant lists of RNA 3D structures provided by the Bowling Green State University RNA group, R3D Align connects users to structure files in the same equivalence class and the best-modeled representative structure from each group. The R3D Align web server is freely accessible at http://rna.bgsu.edu/r3dalign/. PMID:23716643

  17. Nanoscale Analysis of a Hierarchical Hybrid Solar Cell in 3D

    PubMed Central

    Divitini, Giorgio; Stenzel, Ole; Ghadirzadeh, Ali; Guarnera, Simone; Russo, Valeria; Casari, Carlo S; Bassi, Andrea Li; Petrozza, Annamaria; Di Fonzo, Fabio; Schmidt, Volker; Ducati, Caterina

    2014-01-01

    A quantitative method for the characterization of nanoscale 3D morphology is applied to the investigation of a hybrid solar cell based on a novel hierarchical nanostructured photoanode. A cross section of the solar cell device is prepared by focused ion beam milling in a micropillar geometry, which allows a detailed 3D reconstruction of the titania photoanode by electron tomography. It is found that the hierarchical titania nanostructure facilitates polymer infiltration, thus favoring intermixing of the two semiconducting phases, essential for charge separation. The 3D nanoparticle network is analyzed with tools from stochastic geometry to extract information related to the charge transport in the hierarchical solar cell. In particular, the experimental dataset allows direct visualization of the percolation pathways that contribute to the photocurrent. PMID:25834481

  18. 3D MoS2-graphene hybrid aerogels as catalyst for enhanced efficient hydrogen evolution

    NASA Astrophysics Data System (ADS)

    Xu, Xiaobing; Sun, Yuan; Qiao, Wen; Zhang, Xing; Chen, Xing; Song, Xueyin; Wu, Liqian; Zhong, Wei; Du, Youwei

    2017-02-01

    Aerogel composite materials consisting of MoS2 and reduced graphite oxide (rGO) are synthesized by a facile general hydrothermal method, where GO is utilized as a template and provides a novel substrate for the nucleation and subsequent growth of MoS2. These MoS2/rGO hybrid nanostructures exhibit three-dimensional (3D) leaf-like morphology, and show excellent electrocatalytic activities of hydrogen evolution reaction (HER), with a low overpotential of approximately 105 mV, a small Tafel slope of 51 mV/dec and a large exchange current density (j0) of 3.28 × 10-5 A/cm2. The superior electrochemical performance should be attributed to the 3D porous MoS2/rGO hybrid architecture, which enhances the conductivity from graphene to MoS2 as well as the HER activity.

  19. Development of hybrid 3-D hydrological modeling for the NCAR Community Earth System Model (CESM)

    SciTech Connect

    Zeng, Xubin; Troch, Peter; Pelletier, Jon; Niu, Guo-Yue; Gochis, David

    2015-11-15

    This is the Final Report of our four-year (3-year plus one-year no cost extension) collaborative project between the University of Arizona (UA) and the National Center for Atmospheric Research (NCAR). The overall objective of our project is to develop and evaluate the first hybrid 3-D hydrological model with a horizontal grid spacing of 1 km for the NCAR Community Earth System Model (CESM).

  20. Binary 3D image interpolation algorithm based global information and adaptive curves fitting

    NASA Astrophysics Data System (ADS)

    Zhang, Tian-yi; Zhang, Jin-hao; Guan, Xiang-chen; Li, Qiu-ping; He, Meng

    2013-08-01

    Interpolation is a necessary processing step in 3-D reconstruction because of the non-uniform resolution. Conventional interpolation methods simply use two slices to obtain the missing slices between the two slices .when the key slice is missing, those methods may fail to recover it only employing the local information .And the surface of 3D object especially for the medical tissues may be highly complicated, so a single interpolation can hardly get high-quality 3D image. We propose a novel binary 3D image interpolation algorithm. The proposed algorithm takes advantages of the global information. It chooses the best curve adaptively from lots of curves based on the complexity of the surface of 3D object. The results of this algorithm are compared with other interpolation methods on artificial objects and real breast cancer tumor to demonstrate the excellent performance.

  1. Role of bioactive 3D hybrid fibrous scaffolds on mechanical behavior and spatiotemporal osteoblast gene expression.

    PubMed

    Allo, Bedilu A; Lin, Shigang; Mequanint, Kibret; Rizkalla, Amin S

    2013-08-14

    Three-dimensional (3D) bioactive organic-inorganic (O/I) hybrid fibrous scaffolds are attractive extracellular matrix (ECM) surrogates for bone tissue engineering. With the aim of regulating osteoblast gene expression in 3D, a new class of hybrid fibrous scaffolds with two distinct fiber diameters (260 and 600 nm) and excellent physico-mechanical properties were fabricated from tertiary (SiO2-CaO-P2O5) bioactive glass (BG) and poly (ε-caprolactone) (PCL) by in situ sol-gel and electrospinning process. The PCL/BG hybrid fibrous scaffolds exhibited accelerated wetting properties, enhanced pore sizes and porosity, and superior mechanical properties that were dependent on fiber diameter. Contrary to control PCL fibrous scaffolds that were devoid of bonelike apatite particles, incubating PCL/BG hybrid fibrous scaffolds in simulated body fluid (SBF) revealed bonelike apatite deposition. Osteoblast cells cultured on PCL/BG hybrid fibrous scaffolds spread with multiple attachments and actively proliferated suggesting that the low temperature in situ sol-gel and electrospinning process did not have a detrimental effect. Targeted bone-associated gene expressions by rat calvarial osteoblasts seeded on these hybrid scaffolds demonstrated remarkable spatiotemporal gene activation. Transcriptional-level gene expressions for alkaline phosphatase (ALP), osteopontin (OPN), bone sialoprotein (BSP), and osteocalcin (OCN) were significantly higher on the hybrid fibrous scaffolds (p < 0.001) that were largely dependent on fiber diameter compared. Taken together, our results suggest that PCL/BG fibrous scaffolds may accelerate bone formation by providing a favorable microenvironment.

  2. 2D/3D perovskite hybrids as moisture-tolerant and efficient light absorbers for solar cells.

    PubMed

    Ma, Chaoyan; Leng, Chongqian; Ji, Yixiong; Wei, Xingzhan; Sun, Kuan; Tang, Linlong; Yang, Jun; Luo, Wei; Li, Chaolong; Deng, Yunsheng; Feng, Shuanglong; Shen, Jun; Lu, Shirong; Du, Chunlei; Shi, Haofei

    2016-11-03

    The lifetime and power conversion efficiency are the key issues for the commercialization of perovskite solar cells (PSCs). In this paper, the development of 2D/3D perovskite hybrids (CA2PbI4/MAPbIxCl3-x) was firstly demonstrated to be a reliable method to combine their advantages, and provided a new concept for achieving both stable and efficient PSCs through the hybridization of perovskites. 2D/3D perovskite hybrids afforded significantly-improved moisture stability of films and devices without encapsulation in a high humidity of 63 ± 5%, as compared with the 3D perovskite (MAPbIxCl3-x). The 2D/3D perovskite-hybrid film did not undergo any degradation after 40 days, while the 3D perovskite decomposed completely under the same conditions after 8 days. The 2D/3D perovskite-hybrid device maintained 54% of the original efficiency after 220 hours, whereas the 3D perovskite device lost all the efficiency within only 50 hours. Moreover, the 2D/3D perovskite hybrid achieved comparable device performances (PCE: 13.86%) to the 3D perovskite (PCE: 13.12%) after the optimization of device fabrication conditions.

  3. Study of the internal magnetic field of Mercury through 3D hybrid simulations

    NASA Astrophysics Data System (ADS)

    Leclercq, Ludivine; Marcel Chanteur, Gerard; Modolo, Ronan; Leblanc, Francois; Schmidt, Carl; Langlais, Benoît; Thebault, Erwan

    2016-10-01

    In 1974, Mariner 10 discovered the intrinsic magnetic field of Mercury which interacts with the solar wind, leading to the formation of a magnetosphere. In spite of the recent MESSENGER observations, this magnetosphere remains quite unknown, especially in the Southern hemisphere. In order to improve our understanding of the Hermean magnetosphere, and to prepare the Bepi-Colombo mission (ESA/JAXA), we simulated the magnetized environment of Mercury using the model named LatHyS (LATMOS Hybrid Simulation). LatHyS is a 3D parallel multi-species hybrid code which has been applied to Mars, Titan and Ganymede, which has recently be improved by the implementation of a multi-grid method allowing to refine the spatial resolution near the planetary object (40 km in the case of Mercury). In order to investigate the Hermean environment, several hybrid simulations have been performed considering different internal field models, and results are compared with MESSENGER observations.

  4. Local-global alignment for finding 3D similarities in protein structures

    DOEpatents

    Zemla, Adam T.

    2011-09-20

    A method of finding 3D similarities in protein structures of a first molecule and a second molecule. The method comprises providing preselected information regarding the first molecule and the second molecule. Comparing the first molecule and the second molecule using Longest Continuous Segments (LCS) analysis. Comparing the first molecule and the second molecule using Global Distance Test (GDT) analysis. Comparing the first molecule and the second molecule using Local Global Alignment Scoring function (LGA_S) analysis. Verifying constructed alignment and repeating the steps to find the regions of 3D similarities in protein structures.

  5. Bioavailable atmospheric phosphorous supply to the global ocean: a 3-D global modeling study

    NASA Astrophysics Data System (ADS)

    Myriokefalitakis, Stelios; Nenes, Athanasios; Baker, Alex R.; Mihalopoulos, Nikolaos; Kanakidou, Maria

    2016-12-01

    The atmospheric cycle of phosphorus (P) is parameterized here in a state-of-the-art global 3-D chemistry transport model, taking into account primary emissions of total P (TP) and soluble P (DP) associated with mineral dust, combustion particles from natural and anthropogenic sources, bioaerosols, sea spray and volcanic aerosols. For the present day, global TP emissions are calculated to be roughly 1.33 Tg-P yr-1, with the mineral sources contributing more than 80 % to these emissions. The P solubilization from mineral dust under acidic atmospheric conditions is also parameterized in the model and is calculated to contribute about one-third (0.14 Tg-P yr-1) of the global DP atmospheric source. To our knowledge, a unique aspect of our global study is the explicit modeling of the evolution of phosphorus speciation in the atmosphere. The simulated present-day global annual DP deposition flux is 0.45 Tg-P yr-1 (about 40 % over oceans), showing a strong spatial and temporal variability. Present-day simulations of atmospheric P aerosol concentrations and deposition fluxes are satisfactory compared with available observations, indicating however an underestimate of about 70 % on current knowledge of the sources that drive the P atmospheric cycle. Sensitivity simulations using preindustrial (year 1850) anthropogenic and biomass burning emission scenarios showed a present-day increase of 75 % in the P solubilization flux from mineral dust, i.e., the rate at which P is converted into soluble forms, compared to preindustrial times, due to increasing atmospheric acidity over the last 150 years. Future reductions in air pollutants due to the implementation of air-quality regulations are expected to decrease the P solubilization flux from mineral dust by about 30 % in the year 2100 compared to the present day. Considering, however, that all the P contained in bioaerosols is readily available for uptake by marine organisms, and also accounting for all other DP sources, a total

  6. Optimization of a Hybrid Magnetic Bearing for a Magnetically Levitated Blood Pump via 3-D FEA

    PubMed Central

    Cheng, Shanbao; Olles, Mark W.; Burger, Aaron F.; Day, Steven W.

    2011-01-01

    In order to improve the performance of a magnetically levitated (maglev) axial flow blood pump, three-dimensional (3-D) finite element analysis (FEA) was used to optimize the design of a hybrid magnetic bearing (HMB). Radial, axial, and current stiffness of multiple design variations of the HMB were calculated using a 3-D FEA package and verified by experimental results. As compared with the original design, the optimized HMB had twice the axial stiffness with the resulting increase of negative radial stiffness partially compensated for by increased current stiffness. Accordingly, the performance of the maglev axial flow blood pump with the optimized HMBs was improved: the maximum pump speed was increased from 6000 rpm to 9000 rpm (50%). The radial, axial and current stiffness of the HMB was found to be linear at nominal operational position from both 3-D FEA and empirical measurements. Stiffness values determined by FEA and empirical measurements agreed well with one another. The magnetic flux density distribution and flux loop of the HMB were also visualized via 3-D FEA which confirms the designers’ initial assumption about the function of this HMB. PMID:22065892

  7. Optimization of a Hybrid Magnetic Bearing for a Magnetically Levitated Blood Pump via 3-D FEA.

    PubMed

    Cheng, Shanbao; Olles, Mark W; Burger, Aaron F; Day, Steven W

    2011-10-01

    In order to improve the performance of a magnetically levitated (maglev) axial flow blood pump, three-dimensional (3-D) finite element analysis (FEA) was used to optimize the design of a hybrid magnetic bearing (HMB). Radial, axial, and current stiffness of multiple design variations of the HMB were calculated using a 3-D FEA package and verified by experimental results. As compared with the original design, the optimized HMB had twice the axial stiffness with the resulting increase of negative radial stiffness partially compensated for by increased current stiffness. Accordingly, the performance of the maglev axial flow blood pump with the optimized HMBs was improved: the maximum pump speed was increased from 6000 rpm to 9000 rpm (50%). The radial, axial and current stiffness of the HMB was found to be linear at nominal operational position from both 3-D FEA and empirical measurements. Stiffness values determined by FEA and empirical measurements agreed well with one another. The magnetic flux density distribution and flux loop of the HMB were also visualized via 3-D FEA which confirms the designers' initial assumption about the function of this HMB.

  8. Paper/PMMA Hybrid 3D Cell Culture Microfluidic Platform for the Study of Cellular Crosstalk.

    PubMed

    Lei, Kin Fong; Chang, Chih-Hsuan; Chen, Ming-Jie

    2017-04-06

    Studying cellular crosstalk is important for understanding tumor initiation, progression, metastasis, and therapeutic resistance. Moreover, a three-dimensional (3D) cell culture model can provide a more physiologically meaningful culture microenvironment. However, studying cellular crosstalk in a 3D cell culture model involves tedious processing. In this study, a paper/poly(methyl methacrylate) (PMMA) hybrid 3D cell culture microfluidic platform was successfully developed for the study of cellular crosstalk. The platform was a paper substrate with culture microreactors placed on a PMMA substrate with hydrogel-infused channels. Different types of cells were directly seeded and cultured in the microreactors. Aberrant cell proliferation of the affected cells was induced by secretions from transfected cells, and the proliferation ratios were investigated using a colorimetric method. The results showed that the responses of cellular crosstalk were different in different types of cells. Moreover, neutralizing and competitive assays were performed to show the functionality of the platform. Additionally, the triggered signaling pathways of the affected cells were directly analyzed by a subsequent immunoassay. The microfluidic platform provides a simple method for studying cellular crosstalk and the corresponding signaling pathways in a 3D culture model.

  9. Hybrid wide-field and scanning microscopy for high-speed 3D imaging.

    PubMed

    Duan, Yubo; Chen, Nanguang

    2015-11-15

    Wide-field optical microscopy is efficient and robust in biological imaging, but it lacks depth sectioning. In contrast, scanning microscopic techniques, such as confocal microscopy and multiphoton microscopy, have been successfully used for three-dimensional (3D) imaging with optical sectioning capability. However, these microscopic techniques are not very suitable for dynamic real-time imaging because they usually take a long time for temporal and spatial scanning. Here, a hybrid imaging technique combining wide-field microscopy and scanning microscopy is proposed to accelerate the image acquisition process while maintaining the 3D optical sectioning capability. The performance was demonstrated by proof-of-concept imaging experiments with fluorescent beads and zebrafish liver.

  10. Characteristics Analysis on Various Kinds of Hybrid Stepping Motors Using 3D Finite Element Method

    NASA Astrophysics Data System (ADS)

    Enomoto, Yuji; Maki, Kohji; Miyata, Kenji; Oonishi, Kazuo; Sakamoto, Masafumi; Abukawa, Toshimi

    We have presented a powerful scheme of investigating hybrid stepping motor characteristics by using 3D finite element method. A linear magnetic field analysis is effectively applicable to predict relative performance of several motors in an extremely short computing time. The waveforms of cogging torque by linear and nonlinear analysis resemble each other, while the wave amplitude in the linear analysis is about 2 times larger than one in the nonlinear analysis in the presented example. The overestimation factor of cogging torque is approximately constant for the same material composition.

  11. Optical design of wavelength selective CPVT system with 3D/2D hybrid concentration

    NASA Astrophysics Data System (ADS)

    Ahmad, N.; Ijiro, T.; Yamada, N.; Kawaguchi, T.; Maemura, T.; Ohashi, H.

    2012-10-01

    Optical design of a concentrating photovoltaic/thermal (CPVT) system is carried out. Using wavelength-selective optics, the system demonstrates 3-D concentration onto a solar cell and 2-D concentration onto a thermal receiver. Characteristics of the two types of concentrator systems are examined with ray-tracing analysis. The first system is a glazed mirror-based concentrator system mounted on a 2-axis pedestal tracker. The size of the secondary optical element is minimized to decrease the cost of the system, and it has a wavelength-selective function for performing 3-D concentration onto a solar cell and 2-D concentration onto a thermal receiver. The second system is a non-glazed beamdown concentrator system containing parabolic mirrors in the lower part. The beam-down selective mirror performs 3-D concentration onto a solar cell placed above the beam-down selective mirror, and 2-D concentration down to a thermal receiver placed at the bottom level. The system is mounted on a two-axis carousel tracker. A parametric study is performed for those systems with different geometrical 2-D/3-D concentration ratios. Wavelength-selective optics such as hot/cold mirrors and spectrum-splitting technologies are taken into account in the analysis. Results show reduced heat load on the solar cell and increased total system efficiency compared to a non-selective CPV system. Requirements for the wavelength-selective properties are elucidated. It is also shown that the hybrid concept with 2-D concentration onto a thermal receiver and 3-D concentration onto a solar cell has an advantageous geometry because of the high total system efficiency and compatibility with the piping arrangement of the thermal receiver.

  12. The Use of Atomic Force Microscopy for 3D Analysis of Nucleic Acid Hybridization on Microarrays.

    PubMed

    Dubrovin, E V; Presnova, G V; Rubtsova, M Yu; Egorov, A M; Grigorenko, V G; Yaminsky, I V

    2015-01-01

    Oligonucleotide microarrays are considered today to be one of the most efficient methods of gene diagnostics. The capability of atomic force microscopy (AFM) to characterize the three-dimensional morphology of single molecules on a surface allows one to use it as an effective tool for the 3D analysis of a microarray for the detection of nucleic acids. The high resolution of AFM offers ways to decrease the detection threshold of target DNA and increase the signal-to-noise ratio. In this work, we suggest an approach to the evaluation of the results of hybridization of gold nanoparticle-labeled nucleic acids on silicon microarrays based on an AFM analysis of the surface both in air and in liquid which takes into account of their three-dimensional structure. We suggest a quantitative measure of the hybridization results which is based on the fraction of the surface area occupied by the nanoparticles.

  13. Localizing Protein in 3D Neural Stem Cell Culture: a Hybrid Visualization Methodology

    PubMed Central

    Fai, Stephen; Bennett, Steffany A.L.

    2010-01-01

    The importance of 3-dimensional (3D) topography in influencing neural stem and progenitor cell (NPC) phenotype is widely acknowledged yet challenging to study. When dissociated from embryonic or post-natal brain, single NPCs will proliferate in suspension to form neurospheres. Daughter cells within these cultures spontaneously adopt distinct developmental lineages (neurons, oligodendrocytes, and astrocytes) over the course of expansion despite being exposed to the same extracellular milieu. This progression recapitulates many of the stages observed over the course of neurogenesis and gliogenesis in post-natal brain and is often used to study basic NPC biology within a controlled environment. Assessing the full impact of 3D topography and cellular positioning within these cultures on NPC fate is, however, difficult. To localize target proteins and identify NPC lineages by immunocytochemistry, free-floating neurospheres must be plated on a substrate or serially sectioned. This processing is required to ensure equivalent cell permeabilization and antibody access throughout the sphere. As a result, 2D epifluorescent images of cryosections or confocal reconstructions of 3D Z-stacks can only provide spatial information about cell position within discrete physical or digital 3D slices and do not visualize cellular position in the intact sphere. Here, to reiterate the topography of the neurosphere culture and permit spatial analysis of protein expression throughout the entire culture, we present a protocol for isolation, expansion, and serial sectioning of post-natal hippocampal neurospheres suitable for epifluorescent or confocal immunodetection of target proteins. Connexin29 (Cx29) is analyzed as an example. Next, using a hybrid of graphic editing and 3D modelling softwares rigorously applied to maintain biological detail, we describe how to re-assemble the 3D structural positioning of these images and digitally map labelled cells within the complete neurosphere. This

  14. 3D magnetospheric parallel hybrid multi-grid method applied to planet–plasma interactions

    SciTech Connect

    Leclercq, L.; Mancini, M.

    2016-03-15

    We present a new method to exploit multiple refinement levels within a 3D parallel hybrid model, developed to study planet–plasma interactions. This model is based on the hybrid formalism: ions are kinetically treated whereas electrons are considered as a inertia-less fluid. Generally, ions are represented by numerical particles whose size equals the volume of the cells. Particles that leave a coarse grid subsequently entering a refined region are split into particles whose volume corresponds to the volume of the refined cells. The number of refined particles created from a coarse particle depends on the grid refinement rate. In order to conserve velocity distribution functions and to avoid calculations of average velocities, particles are not coalesced. Moreover, to ensure the constancy of particles' shape function sizes, the hybrid method is adapted to allow refined particles to move within a coarse region. Another innovation of this approach is the method developed to compute grid moments at interfaces between two refinement levels. Indeed, the hybrid method is adapted to accurately account for the special grid structure at the interfaces, avoiding any overlapping grid considerations. Some fundamental test runs were performed to validate our approach (e.g. quiet plasma flow, Alfven wave propagation). Lastly, we also show a planetary application of the model, simulating the interaction between Jupiter's moon Ganymede and the Jovian plasma.

  15. 3D Scene Reconstruction Using Omnidirectional Vision and LiDAR: A Hybrid Approach

    PubMed Central

    Vlaminck, Michiel; Luong, Hiep; Goeman, Werner; Philips, Wilfried

    2016-01-01

    In this paper, we propose a novel approach to obtain accurate 3D reconstructions of large-scale environments by means of a mobile acquisition platform. The system incorporates a Velodyne LiDAR scanner, as well as a Point Grey Ladybug panoramic camera system. It was designed with genericity in mind, and hence, it does not make any assumption about the scene or about the sensor set-up. The main novelty of this work is that the proposed LiDAR mapping approach deals explicitly with the inhomogeneous density of point clouds produced by LiDAR scanners. To this end, we keep track of a global 3D map of the environment, which is continuously improved and refined by means of a surface reconstruction technique. Moreover, we perform surface analysis on consecutive generated point clouds in order to assure a perfect alignment with the global 3D map. In order to cope with drift, the system incorporates loop closure by determining the pose error and propagating it back in the pose graph. Our algorithm was exhaustively tested on data captured at a conference building, a university campus and an industrial site of a chemical company. Experiments demonstrate that it is capable of generating highly accurate 3D maps in very challenging environments. We can state that the average distance of corresponding point pairs between the ground truth and estimated point cloud approximates one centimeter for an area covering approximately 4000 m2. To prove the genericity of the system, it was tested on the well-known Kitti vision benchmark. The results show that our approach competes with state of the art methods without making any additional assumptions. PMID:27854315

  16. 3D Scene Reconstruction Using Omnidirectional Vision and LiDAR: A Hybrid Approach.

    PubMed

    Vlaminck, Michiel; Luong, Hiep; Goeman, Werner; Philips, Wilfried

    2016-11-16

    In this paper, we propose a novel approach to obtain accurate 3D reconstructions of large-scale environments by means of a mobile acquisition platform. The system incorporates a Velodyne LiDAR scanner, as well as a Point Grey Ladybug panoramic camera system. It was designed with genericity in mind, and hence, it does not make any assumption about the scene or about the sensor set-up. The main novelty of this work is that the proposed LiDAR mapping approach deals explicitly with the inhomogeneous density of point clouds produced by LiDAR scanners. To this end, we keep track of a global 3D map of the environment, which is continuously improved and refined by means of a surface reconstruction technique. Moreover, we perform surface analysis on consecutive generated point clouds in order to assure a perfect alignment with the global 3D map. In order to cope with drift, the system incorporates loop closure by determining the pose error and propagating it back in the pose graph. Our algorithm was exhaustively tested on data captured at a conference building, a university campus and an industrial site of a chemical company. Experiments demonstrate that it is capable of generating highly accurate 3D maps in very challenging environments. We can state that the average distance of corresponding point pairs between the ground truth and estimated point cloud approximates one centimeter for an area covering approximately 4000 m 2 . To prove the genericity of the system, it was tested on the well-known Kitti vision benchmark. The results show that our approach competes with state of the art methods without making any additional assumptions.

  17. Compilation of 3D global conductivity model of the Earth for space weather applications

    NASA Astrophysics Data System (ADS)

    Alekseev, Dmitry; Kuvshinov, Alexey; Palshin, Nikolay

    2015-07-01

    We have compiled a global three-dimensional (3D) conductivity model of the Earth with an ultimate goal to be used for realistic simulation of geomagnetically induced currents (GIC), posing a potential threat to man-made electric systems. Bearing in mind the intrinsic frequency range of the most intense disturbances (magnetospheric substorms) with typical periods ranging from a few minutes to a few hours, the compiled 3D model represents the structure in depth range of 0-100 km, including seawater, sediments, earth crust, and partly the lithosphere/asthenosphere. More explicitly, the model consists of a series of spherical layers, whose vertical and lateral boundaries are established based on available data. To compile a model, global maps of bathymetry, sediment thickness, and upper and lower crust thicknesses as well as lithosphere thickness are utilized. All maps are re-interpolated on a common grid of 0.25×0.25 degree lateral spacing. Once the geometry of different structures is specified, each element of the structure is assigned either a certain conductivity value or conductivity versus depth distribution, according to available laboratory data and conversion laws. A numerical formalism developed for compilation of the model, allows for its further refinement by incorporation of regional 3D conductivity distributions inferred from the real electromagnetic data. So far we included into our model four regional conductivity models, available from recent publications, namely, surface conductance model of Russia, and 3D conductivity models of Fennoscandia, Australia, and northwest of the United States.

  18. Application of a hybrid 3D-2D laser scanning system to the characterization of slate slabs.

    PubMed

    López, Marcos; Martínez, Javier; Matías, José María; Vilán, José Antonio; Taboada, Javier

    2010-01-01

    Dimensional control based on 3D laser scanning techniques is widely used in practice. We describe the application of a hybrid 3D-2D laser scanning system to the characterization of slate slabs with structural defects that are difficult for the human eye to characterize objectively. Our study is based on automating the process using a 3D laser scanner and a 2D camera. Our results demonstrate that the application of this hybrid system optimally characterizes slate slabs in terms of the defects described by the Spanish UNE-EN 12326-1 standard.

  19. Automatic 3D liver segmentation based on deep learning and globally optimized surface evolution.

    PubMed

    Hu, Peijun; Wu, Fa; Peng, Jialin; Liang, Ping; Kong, Dexing

    2016-12-21

    The detection and delineation of the liver from abdominal 3D computed tomography (CT) images are fundamental tasks in computer-assisted liver surgery planning. However, automatic and accurate segmentation, especially liver detection, remains challenging due to complex backgrounds, ambiguous boundaries, heterogeneous appearances and highly varied shapes of the liver. To address these difficulties, we propose an automatic segmentation framework based on 3D convolutional neural network (CNN) and globally optimized surface evolution. First, a deep 3D CNN is trained to learn a subject-specific probability map of the liver, which gives the initial surface and acts as a shape prior in the following segmentation step. Then, both global and local appearance information from the prior segmentation are adaptively incorporated into a segmentation model, which is globally optimized in a surface evolution way. The proposed method has been validated on 42 CT images from the public Sliver07 database and local hospitals. On the Sliver07 online testing set, the proposed method can achieve an overall score of [Formula: see text], yielding a mean Dice similarity coefficient of [Formula: see text], and an average symmetric surface distance of [Formula: see text] mm. The quantitative validations and comparisons show that the proposed method is accurate and effective for clinical application.

  20. Automatic 3D liver segmentation based on deep learning and globally optimized surface evolution

    NASA Astrophysics Data System (ADS)

    Hu, Peijun; Wu, Fa; Peng, Jialin; Liang, Ping; Kong, Dexing

    2016-12-01

    The detection and delineation of the liver from abdominal 3D computed tomography (CT) images are fundamental tasks in computer-assisted liver surgery planning. However, automatic and accurate segmentation, especially liver detection, remains challenging due to complex backgrounds, ambiguous boundaries, heterogeneous appearances and highly varied shapes of the liver. To address these difficulties, we propose an automatic segmentation framework based on 3D convolutional neural network (CNN) and globally optimized surface evolution. First, a deep 3D CNN is trained to learn a subject-specific probability map of the liver, which gives the initial surface and acts as a shape prior in the following segmentation step. Then, both global and local appearance information from the prior segmentation are adaptively incorporated into a segmentation model, which is globally optimized in a surface evolution way. The proposed method has been validated on 42 CT images from the public Sliver07 database and local hospitals. On the Sliver07 online testing set, the proposed method can achieve an overall score of 80.3+/- 4.5 , yielding a mean Dice similarity coefficient of 97.25+/- 0.65 % , and an average symmetric surface distance of 0.84+/- 0.25 mm. The quantitative validations and comparisons show that the proposed method is accurate and effective for clinical application.

  1. QUASI-OPTICAL 3-dB HYBRID FOR FUTURE HIGH-ENERGY ACCELERATORS

    SciTech Connect

    Jay L. Hirshfield

    2005-12-15

    Phase-controlled wave combiners-commutators and isolators for protecting rf sources against reflection from the accelerating structure can be built using a 3-dB hybrid built around a metallic grating used in a ''magic-Y'' configuration. Models of the magic-Y were designed and tested, both at 34.272 GHz using the Omega-P Ka-band magnicon, and at 11.424 GHz using the Omega-P/NRL X-band magnicon. All elements of the magic-Y were optimized analytically and numerically. A non-vacuum 34 GHz model of the magic Y was built and tested experimentally at a low power. An engineering design for the high power (vacuum) compressor was configured. Similar steps were taken for the 11-GHz version.

  2. A hybrid metalloarsenate 3D framework-1D interrupted metal oxide.

    PubMed

    Hughes, Robert W; Gerrard, Lee A; Price, Daniel J; Weller, Mark T

    2003-06-30

    Complex metal arsenates of the stoichiometry M(1)(-)(x)()M'(6)(OH)(3)(AsO(4)H(2)(x)()(/3))(3)(HAsO(4)), M = M' = Co, Ni, have been synthesized under hydrothermal conditions. The two compounds display a very similar structural topology to that of the mineral dumortierite, an uncommon complex oxyborosilicate of aluminum. The hybrid structures consist of well separated, vacancy interrupted chains of face sharing MO(6) octahedra, with short M.M distances near 2.5 A, embedded in a metalloarsenate 3D framework having the topology of the aluminosilicate cancrinite. The framework also contains a quadruply bridging hydroxide ion. Magnetic susceptibility measurements reveal a strong antiferromagnetic interaction and magnetic transition to low temperature spin canted phases below 51 K (Co) and 42 K (Ni). The material may be considered as a zeotype framework structure templated by an interrupted one-dimensional metal oxide.

  3. 3D hybrid simulations with gyrokinetic particle ions and fluid electrons

    SciTech Connect

    Belova, E.V.; Park, W.; Fu, G.Y.; Strauss, H.R.; Sugiyama, L.E.

    1998-12-31

    The previous hybrid MHD/particle model (MH3D-K code) represented energetic ions as gyrokinetic (or drift-kinetic) particles coupled to MHD equations using the pressure or current coupling scheme. A small energetic to bulk ion density ratio was assumed, n{sub h}/n{sub b} {much_lt} 1, allowing the neglect of the energetic ion perpendicular inertia in the momentum equation and the use of MHD Ohm`s law E = {minus}v{sub b} {times} B. A generalization of this model in which all ions are treated as gyrokinetic/drift-kinetic particles and fluid description is used for the electron dynamics is considered in this paper.

  4. Supergravity Analysis of Hybrid Inflation Model from D3--D7 System

    SciTech Connect

    Koyama, Fumikazu; Tachikawa, Yuji; Watari, Taizan

    2003-11-20

    The slow-roll inflation is a beautiful paradigm, yet the inflaton potential can hardly be sufficiently flat when unknown gravitational effects are taken into account. However, the hybrid inflation models constructed in D = 4 N = 1 supergravity can be consistent with N = 2 supersymmetry, and can be naturally embedded into string theory. This article discusses the gravitational effects carefully in the string model, using D = 4 supergravity description. We adopt the D3--D7 system of Type IIB string theory compactified on K3 x T^2/Z_2 orientifold for definiteness. It turns out that the slow-roll parameter can be sufficiently small despite the non-minimal Kahler potential of the model. The conditions for this to happen are clarified in terms of string vacua. We also find that the geometry obtained by blowing up singularity, which is necessary for the positive vacuum energy, is stabilized by introducing certain 3-form fluxes.

  5. 3D Ag/ZnO hybrids for sensitive surface-enhanced Raman scattering detection

    NASA Astrophysics Data System (ADS)

    Huang, Chenyue; Xu, Chunxiang; Lu, Junfeng; Li, Zhaohui; Tian, Zhengshan

    2016-03-01

    To combine the surface plasma resonance of metal and local field enhancement in metal/semiconductor interface, Ag nanoparticles (NPs) were assembled on a ZnO nanorod array which was grown by hydrothermally on carbon fibers. The construction of dimensional (3D) Surface-Enhanced Raman Scattering (SERS) substrate is used for the sensitive detection of organic pollutants with the advantages such as facile synthesis, short detection time and low cost. The hybrid substrate was manifested a high sensitivity to phenol red at a lower concentration of 1 × 10-9 M and a higher enhancement factor of 3.18 × 109. Moreover, the ZnO nanostructures decorated with Ag NPs were demonstrated self-cleaning function under UV irradiation via photocatalytic degradation of the analytic molecules. The fabrication process of the materials and sensors, optimization of the SERS behaviors for different sized Ag NPs, the mechanism of SERS and recovery were presented with a detailed discussion.

  6. Variational formulation of hybrid problems for fully 3-D transonic flow with shocks in rotor

    NASA Technical Reports Server (NTRS)

    Liu, Gao-Lian

    1991-01-01

    Based on previous research, the unified variable domain variational theory of hybrid problems for rotor flow is extended to fully 3-D transonic rotor flow with shocks, unifying and generalizing the direct and inverse problems. Three variational principles (VP) families were established. All unknown boundaries and flow discontinuities (such as shocks, free trailing vortex sheets) are successfully handled via functional variations with variable domain, converting almost all boundary and interface conditions, including the Rankine Hugoniot shock relations, into natural ones. This theory provides a series of novel ways for blade design or modification and a rigorous theoretical basis for finite element applications and also constitutes an important part of the optimal design theory of rotor bladings. Numerical solutions to subsonic flow by finite elements with self-adapting nodes given in Refs., show good agreement with experimental results.

  7. 3D myofibril imaging in live cardiomyocytes via hybrid SHG-TPEF microscopy

    NASA Astrophysics Data System (ADS)

    Shao, Yonghong; Liu, Honghai; Ye, Tong; Borg, Tom; Qu, Junle; Peng, Xiang; Niu, Hanben; Gao, Bruce

    2011-03-01

    We developed a hybrid SHG-TPEF polarization imaging system that allowed the excitation beam from an fs Ti:Sappire laser being bi-directionally raster scanned across the focal plane using a pair of orthogonal galvanometers. To implement high-speed scanning, the turning regions of the triangular waves were smoothed by a custom-designed waveform. The SHG and TPEF signals from samples were recorded by two PMTs in the forward and backward direction. Using this imaging system, we obtained 3D images of the sarcomere structure via SHG and DiO-stained lipid membrane via TPEF in live cardiomyocytes isolated from neonatal and adult rats. The results demonstrated the potential applications of SHG and TPEF in the research of myofibrillogensis.

  8. 3D hybrid modeling of the plasma environment near Titan for T5 encounter

    NASA Astrophysics Data System (ADS)

    Lipatov, A. S.; Sittler, E. C., Jr.; Hartle, R. E.; Cooper, J. F.; Sarantos, M.

    2012-09-01

    Wave-particle interactions play a very important role in the plasma dynamics near Titan: mass loading, excitation of low-frequency waves and formation of the particle velocity distribution function (e.g. ring/shelllike distributions, etc.) The kinetic approach is important for estimating collision processes; e.g., charge exchange. In this report we discuss results of 3D hybrid modeling of the interaction between Saturn's magnetosphere and Titan's atmosphere/ionosphere for T5 encounter. T5 flyby is the only encounter when the 2 main ionizating sources of Titan atmosphere, solar radiation and corotating plasma, align quasi-antiparallel. The modeling is based on recent analysis of the Cassini Plasma Spectrometer (CAPS) and the Cassini Ion, and Neutral Mass Spectrometer (INMS) measurements during the T5 flyby through Titan's ram-side and polar ionosphere [1, 2]. Magnetic field data was used from the MAG instrument [3]. In our model the background ions (O+, H+), all pickup ions, and ionospheric ions are considered as a particles, whereas the electrons are described as a fluid (see e.g. [4]). Inhomogeneous photoionization (in the dayside ionosphere), electron-impact ionization, and charge exchange are included in our model. The temperature of the background electrons and pickup electrons was also incorporated into the generalized Ohm's law. We also take into account collisions between ions and neutrals. In our hybrid simulations we use Chamberlain profiles for the exosphere's components. The moon is considered as a weakly conducting body. The first results of our hybridmodeling show a strong asymmetry in the background (H+, O+) and pickup (H+2 , N+2 ,CH+4 ) ion density profiles. Such strong asymmetry cannot be explained by a single-fluid multi-species 3D MHD model [5], which included complex chemistry but does not produce finite gyroradius and kinetic effects.

  9. Advanced Li-Ion Hybrid Supercapacitors Based on 3D Graphene-Foam Composites.

    PubMed

    Liu, Wenwen; Li, Jingde; Feng, Kun; Sy, Abel; Liu, Yangshuai; Lim, Lucas; Lui, Gregory; Tjandra, Ricky; Rasenthiram, Lathankan; Chiu, Gordon; Yu, Aiping

    2016-10-05

    Li-ion hybrid supercapacitors (LIHSs) have recently attracted increasing attention as a new and promising energy storage device. However, it is still a great challenge to construct novel LIHSs with high-performance due to the majority of battery-type anodes retaining the sluggish kinetics of Li-ion storage and most capacitor-type cathodes with low specific capacitance. To solve this problem, 3D graphene-wrapped MoO3 nanobelt foam with the unique porous network structure has been designed and prepared as anode material, which delivers high capacity, improved rate performance, and enhanced cycle stability. First-principles calculation reveals that the combination of graphene dramatically reduces the diffusion energy barrier of Li(+) adsorbed on the surface of MoO3 nanobelt, thus improving its electrochemical performance. Furthermore, 3D graphene-wrapped polyaniline nanotube foam derived carbon is employed as a new type of capacitor-type cathode, demonstrating high specific capacitance, good rate performance, and long cycle stability. Benefiting from these two graphene foam-enhanced materials, the constructed LIHSs show a wide operating voltage range (3.8 V), a long stable cycle life (90% capacity retention after 3000 cycles), a high energy density (128.3 Wh·kg(-1)), and a high power density (13.5 kW·kg(-1)). These encouraging performances indicate that the obtained LIHSs may have promising prospect as next-generation energy-storage devices.

  10. A hybrid method for inversion of 3D DC resistivity logging measurements.

    PubMed

    Gajda-Zagórska, Ewa; Schaefer, Robert; Smołka, Maciej; Paszyński, Maciej; Pardo, David

    This paper focuses on the application of hp hierarchic genetic strategy (hp-HGS) for solution of a challenging problem, the inversion of 3D direct current (DC) resistivity logging measurements. The problem under consideration has been formulated as the global optimization one, for which the objective function (misfit between computed and reference data) exhibits multiple minima. In this paper, we consider the extension of the hp-HGS strategy, namely we couple the hp-HGS algorithm with a gradient based optimization method for a local search. Forward simulations are performed with a self-adaptive hp finite element method, hp-FEM. The computational cost of misfit evaluation by hp-FEM depends strongly on the assumed accuracy. This accuracy is adapted to the tree of populations generated by the hp-HGS algorithm, which makes the global phase significantly cheaper. Moreover, tree structure of demes as well as branch reduction and conditional sprouting mechanism reduces the number of expensive local searches up to the number of minima to be recognized. The common (direct and inverse) accuracy control, crucial for the hp-HGS efficiency, has been motivated by precise mathematical considerations. Numerical results demonstrate the suitability of the proposed method for the inversion of 3D DC resistivity logging measurements.

  11. External force back-projective composition and globally deformable optimization for 3-D coronary artery reconstruction.

    PubMed

    Yang, Jian; Cong, Weijian; Chen, Yang; Fan, Jingfan; Liu, Yue; Wang, Yongtian

    2014-02-21

    The clinical value of the 3D reconstruction of a coronary artery is important for the diagnosis and intervention of cardiovascular diseases. This work proposes a method based on a deformable model for reconstructing coronary arteries from two monoplane angiographic images acquired from different angles. First, an external force back-projective composition model is developed to determine the external force, for which the force distributions in different views are back-projected to the 3D space and composited in the same coordinate system based on the perspective projection principle of x-ray imaging. The elasticity and bending forces are composited as an internal force to maintain the smoothness of the deformable curve. Second, the deformable curve evolves rapidly toward the true vascular centerlines in 3D space and angiographic images under the combination of internal and external forces. Third, densely matched correspondence among vessel centerlines is constructed using a curve alignment method. The bundle adjustment method is then utilized for the global optimization of the projection parameters and the 3D structures. The proposed method is validated on phantom data and routine angiographic images with consideration for space and re-projection image errors. Experimental results demonstrate the effectiveness and robustness of the proposed method for the reconstruction of coronary arteries from two monoplane angiographic images. The proposed method can achieve a mean space error of 0.564 mm and a mean re-projection error of 0.349 mm.

  12. Probabilistic intra-retinal layer segmentation in 3-D OCT images using global shape regularization.

    PubMed

    Rathke, Fabian; Schmidt, Stefan; Schnörr, Christoph

    2014-07-01

    With the introduction of spectral-domain optical coherence tomography (OCT), resulting in a significant increase in acquisition speed, the fast and accurate segmentation of 3-D OCT scans has become evermore important. This paper presents a novel probabilistic approach, that models the appearance of retinal layers as well as the global shape variations of layer boundaries. Given an OCT scan, the full posterior distribution over segmentations is approximately inferred using a variational method enabling efficient probabilistic inference in terms of computationally tractable model components: Segmenting a full 3-D volume takes around a minute. Accurate segmentations demonstrate the benefit of using global shape regularization: We segmented 35 fovea-centered 3-D volumes with an average unsigned error of 2.46 ± 0.22 μm as well as 80 normal and 66 glaucomatous 2-D circular scans with errors of 2.92 ± 0.5 μm and 4.09 ± 0.98 μm respectively. Furthermore, we utilized the inferred posterior distribution to rate the quality of the segmentation, point out potentially erroneous regions and discriminate normal from pathological scans. No pre- or postprocessing was required and we used the same set of parameters for all data sets, underlining the robustness and out-of-the-box nature of our approach.

  13. Single-Particle Cryo-EM and 3D Reconstruction of Hybrid Nanoparticles with Electron-Dense Components.

    PubMed

    Yu, Guimei; Yan, Rui; Zhang, Chuan; Mao, Chengde; Jiang, Wen

    2015-10-01

    Single-particle cryo-electron microscopy (cryo-EM), accompanied with 3D reconstruction, is a broadly applicable tool for the structural characterization of macromolecules and nanoparticles. Recently, the cryo-EM field has pushed the limits of this technique to higher resolutions and samples of smaller molecular mass, however, some samples still present hurdles to this technique. Hybrid particles with electron-dense components, which have been studied using single-particle cryo-EM yet with limited success in 3D reconstruction due to the interference caused by electron-dense elements, constitute one group of such challenging samples. To process such hybrid particles, a masking method is developed in this work to adaptively remove pixels arising from electron-dense portions in individual projection images while maintaining maximal biomass signals for subsequent 2D alignment, 3D reconstruction, and iterative refinements. As demonstrated by the success in 3D reconstruction of an octahedron DNA/gold hybrid particle, which has been previously published without a 3D reconstruction, the devised strategy that combines adaptive masking and standard single-particle 3D reconstruction approach has overcome the hurdle of electron-dense elements interference, and is generally applicable to cryo-EM structural characterization of most, if not all, hybrid nanomaterials with electron-dense components.

  14. Earthscape, a Multi-Purpose Interactive 3d Globe Viewer for Hybrid Data Visualization and Analysis

    NASA Astrophysics Data System (ADS)

    Sarthou, A.; Mas, S.; Jacquin, M.; Moreno, N.; Salamon, A.

    2015-08-01

    The hybrid visualization and interaction tool EarthScape is presented here. The software is able to display simultaneously LiDAR point clouds, draped videos with moving footprint, volume scientific data (using volume rendering, isosurface and slice plane), raster data such as still satellite images, vector data and 3D models such as buildings or vehicles. The application runs on touch screen devices such as tablets. The software is based on open source libraries, such as OpenSceneGraph, osgEarth and OpenCV, and shader programming is used to implement volume rendering of scientific data. The next goal of EarthScape is to perform data analysis using ENVI Services Engine, a cloud data analysis solution. EarthScape is also designed to be a client of Jagwire which provides multisource geo-referenced video fluxes. When all these components will be included, EarthScape will be a multi-purpose platform that will provide at the same time data analysis, hybrid visualization and complex interactions. The software is available on demand for free at france@exelisvis.com.

  15. A fast hybrid (3-D/1-D) model for thermal radiative transfer in cirrus via successive orders of scattering

    NASA Astrophysics Data System (ADS)

    Fauchez, Thomas; Davis, Anthony B.; Cornet, Céline; Szczap, Fredéric; Platnick, Steven; Dubuisson, Philippe; Thieuleux, François

    2017-01-01

    We investigate the impact of cirrus cloud heterogeneity on the direct emission by cloud or surface and on the scattering by ice particles in the thermal infrared (TIR). Realistic 3-D cirri are modeled with the 3DCLOUD code, and top-of-atmosphere radiances are simulated by the 3-D Monte Carlo radiative transfer (RT) algorithm 3DMCPOL for two (8.65 μm and 12.05 μm) channels of the Imaging Infrared Radiometer on CALIPSO. At nadir, comparisons of 1-D and 3-D RT show that 3-D radiances are larger than their 1-D counterparts for direct emission but smaller for scattered radiation. For our cirrus cases, 99% of the 3-D total radiance is computed by the third scattering order, which corresponds to 90% of the total computational effort, but larger optical thicknesses need more scattering orders. To radically accelerate the 3-D RT computations (using only few percent of 3-D RT time with a Monte Carlo code), even in the presence of large optical depths, we develop a hybrid model based on exact 3-D direct emission, the first scattering order from 1-D in each homogenized column, and an empirical adjustment linearly dependent on the optical thickness to account for higher scattering orders. Good agreement is found between the hybrid model and the exact 3-D radiances for two very different cirrus models without changing the empirical parameters. We anticipate that a future deterministic implementation of the hybrid model will be fast enough to process multiangle thermal imagery in a practical tomographic reconstruction of 3-D cirrus fields.

  16. A Fast Hybrid (3-D/1-D) Model for Thermal Radiative Transfer in Cirrus via Successive Orders of Scattering

    NASA Technical Reports Server (NTRS)

    Fauchez, Thomas; Davis, Anthony B.; Cornet, Celine; Szczap, Frederic; Platnick, Steven; Dubuisson, Philippe; Thieuleux, Francois

    2017-01-01

    We investigate the impact of cirrus cloud heterogeneity on the direct emission by cloud or surface and on the scattering by ice particles in the thermal infrared (TIR). Realistic 3-D cirri are modeled with the 3DCLOUD code, and top-of-atmosphere radiances are simulated by the 3-D Monte Carlo radiative transfer (RT) algorithm 3DMCPOL for two (8.65 micrometers and 12.05 micrometers) channels of the Imaging Infrared Radiometer on CALIPSO. At nadir, comparisons of 1-D and 3-D RT show that 3-D radiances are larger than their 1-D counterparts for direct emission but smaller for scattered radiation. For our cirrus cases, 99% of the 3-D total radiance is computed by the third scattering order, which corresponds to 90% of the total computational effort, but larger optical thicknesses need more scattering orders. To radically accelerate the 3-D RT computations (using only few percent of 3-D RT time with a Monte Carlo code), even in the presence of large optical depths, we develop a hybrid model based on exact 3-D direct emission, the first scattering order from 1-D in each homogenized column, and an empirical adjustment linearly dependent on the optical thickness to account for higher scattering orders. Good agreement is found between the hybrid model and the exact 3-D radiances for two very different cirrus models without changing the empirical parameters. We anticipate that a future deterministic implementation of the hybrid model will be fast enough to process multiangle thermal imagery in a practical tomographic reconstruction of 3-D cirrus fields.

  17. Effects of Na+ and He+ pickup ions on the lunar plasma environment: 3D hybrid modeling

    NASA Astrophysics Data System (ADS)

    Lipatov, A. S.; Cooper, J. F.; Sittler, E. C.; Hartle, R. E.; Sarantos, M.

    2011-12-01

    The hybrid kinetic model used here supports comprehensive simulation of the interaction between different spatial and energetic elements of the moon-solar wind-magnetosphere of the Earth system. There is a set of MHD,kinetic, hybrid, drift kinetic, electrostatic and full kinetic modeling of the lunar plasma environment [1]. However, observations show the existence of several species of the neutrals and pickup ions like Na, He, K, O etc., (see e.g., [2,3,4]). The solar wind parameters are chosen from the ARTEMIS observations [5]. The Na+, He+ lunar exosphere's parameters are chosen from [6,7]. The hybrid kinetic model allows us to take into account the finite gyroradius effects of pickup ions and to correctly estimate the ions velocity distribution and the fluxes along the magnetic field, and on the lunar surface. Modeling shows the formation of the asymmetric Mach cone, the structuring of the pickup ion tails, and presents another type of lunar-solar wind interaction. We will compare the results of our modeling with observed distributions. References [1] Lipatov, A.S., and Cooper, J.F., Hybrid kinetic modeling of the Lunar plasma environment: Past, present and future. In: Lunar Dust, Plasma and Atmosphere: The Next Steps, January 27-29, 2010, Boulder, Colorado, Abstracts/lpa2010.colorado.edu/. [2] Potter, A.E., and Morgan, T.H., Discovery of sodium and potassium vapor in the atmosphere of the Moon, Science, 241, 675-680, doi:10.1126/science.241.4866.675, 1988. [3] Tyler, A.L., et al., Observations of sodium in the tenuous lunar atmosphere, Geophys. Res. Lett., 15(10), 1141-1144, doi:10.1029/GL015i010p01141, 1988. [4] Tanaka, T., et al., First in situ observation of the Moon-originating ions in the Earth's Magnetosphere by MAP-PACE on SELENE (KAGUYA), Geophys. Res. Lett., 36, L22106, doi:10.1029/2009GL040682, 2009. [5] Wiehle, S., et al., First Lunar Wake Passage of ARTEMIS: Discrimination of Wake Effects and Solar Wind Fluctuations by 3D Hybrid Simulations, Planet

  18. Multi and mixed 3D-printing of graphene-hydroxyapatite hybrid materials for complex tissue engineering.

    PubMed

    Jakus, Adam E; Shah, Ramille N

    2017-01-01

    With the emergence of three-dimensional (3D)-printing (3DP) as a vital tool in tissue engineering and medicine, there is an ever growing need to develop new biomaterials that can be 3D-printed and also emulate the compositional, structural, and functional complexities of human tissues and organs. In this work, we probe the 3D-printable biomaterials spectrum by combining two recently established functional 3D-printable particle-laden biomaterial inks: one that contains hydroxyapatite microspheres (hyperelastic bone, HB) and another that contains graphene nanoflakes (3D-graphene, 3DG). We demonstrate that not only can these distinct, osteogenic, and neurogenic inks be co-3D-printed to create complex, multimaterial constructs, but that composite inks of HB and 3DG can also be synthesized. Specifically, the printability, microstructural, mechanical, electrical, and biological properties of a hybrid material comprised of 1:1 HA:graphene by volume is investigated. The resulting HB-3DG hybrid exhibits mixed characteristics of the two distinct systems, while maintaining 3D-printability, electrical conductivity, and flexibility. In vitro assessment of HB-3DG using mesenchymal stem cells demonstrates the hybrid material supports cell viability and proliferation, as well as significantly upregulates both osteogenic and neurogenic gene expression over 14 days. This work ultimately demonstrates a significant step forward towards being able to 3D-print graded, multicompositional, and multifunctional constructs from hybrid inks for complex composite tissue engineering. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 274-283, 2017.

  19. The performance of semilocal and hybrid density functionals in 3d transition-metal chemistry

    NASA Astrophysics Data System (ADS)

    Furche, Filipp; Perdew, John P.

    2006-01-01

    We investigate the performance of contemporary semilocal and hybrid density functionals for bond energetics, structures, dipole moments, and harmonic frequencies of 3d transition-metal (TM) compounds by comparison with gas-phase experiments. Special attention is given to the nonempirical metageneralized gradient approximation (meta-GGA) of Tao, Perdew, Staroverov, and Scuseria (TPSS) [Phys. Rev. Lett. 91, 146401 (2003)], which has been implemented in TURBOMOLE for the present work. Trends and error patterns for classes of homologous compounds are analyzed, including dimers, monohydrides, mononitrides, monoxides, monofluorides, polyatomic oxides and halogenides, carbonyls, and complexes with organic π ligands such as benzene and cyclopentadienyl. Weakly bound systems such as Ca2, Mn2, and Zn2 are discussed. We propose a reference set of reaction energies for benchmark purposes. Our all-electron results with quadruple zeta valence basis sets validate semilocal density-functional theory as the workhorse of computational TM chemistry. Typical errors in bond energies are substantially larger than in (organic) main group chemistry, however. The Becke-Perdew'86 [Phys. Rev. A 38, 3098 (1988); Phys. Rev. B 33, 8822 (1986)] GGA and the TPSS meta-GGA have the best price/performance ratio, while the TPSS hybrid functional achieves a slightly lower mean absolute error in bond energies. The popular Becke three-parameter hybrid B3LYP underbinds significantly and tends to overestimate bond distances; we give a possible explanation for this. We further show that hybrid mixing does not reduce the width of the error distribution on our reference set. The error of a functional for the s-d transfer energy of a TM atom does not predict its error for TM bond energies and bond lengths. For semilocal functionals, self-interaction error in one- and three-electron bonds appears to be a major source of error in TM reaction energies. Nevertheless, TPSS predicts the correct ground

  20. Global gyrokinetic models for energetic particle driven Alfvén instabilities in 3D equilibria

    NASA Astrophysics Data System (ADS)

    Spong, Don; Holod, Ihor

    2015-11-01

    The GTC global gyrokinetic PIC model has been adapted to 3D VMEC equilibria and provides a new method for the analysis of Alfvénic instabilities in stellarators, 3D tokamaks, and helical RFP states. The gyrokinetic orderings (k||/k⊥ << 1, ω/Ωci << 1, ρEP/L << 1) are applicable to a range of energetic particle driven instabilities that have been observed in 3D configurations. Applications of this model to stellarators have indicated that a variety of different Alfvén instabilities can be excited, depending on the toroidal mode number, fast ion average energy and fast ion density profile. Both an LHD discharge where bursting n = 1 Alfvén activity in the TAE gap was observed and a W7-X case have been examined. TAE,/EAE/GAE modes have been found in the simulations, depending on the mode family and fast ion profiles used. The dynamical evolution of the instabilities shows the field period coupling between n and n + Nfp expected for a stellarator. The development of gyrofluid reduced models that can capture relevant physics aspects of the gyrokinetic models will also be discussed. Research sponsored by the U.S. Department of Energy under Contract DE-AC05-00OR22725 with UT-Battelle, LLC and the GSEP SciDAC Center.

  1. 3D Higher Order Modeling in the BEM/FEM Hybrid Formulation

    NASA Technical Reports Server (NTRS)

    Fink, P. W.; Wilton, D. R.

    2000-01-01

    Higher order divergence- and curl-conforming bases have been shown to provide significant benefits, in both convergence rate and accuracy, in the 2D hybrid finite element/boundary element formulation (P. Fink and D. Wilton, National Radio Science Meeting, Boulder, CO, Jan. 2000). A critical issue in achieving the potential for accuracy of the approach is the accurate evaluation of all matrix elements. These involve products of high order polynomials and, in some instances, singular Green's functions. In the 2D formulation, the use of a generalized Gaussian quadrature method was found to greatly facilitate the computation and to improve the accuracy of the boundary integral equation self-terms. In this paper, a 3D, hybrid electric field formulation employing higher order bases and higher order elements is presented. The improvements in convergence rate and accuracy, compared to those resulting from lower order modeling, are established. Techniques developed to facilitate the computation of the boundary integral self-terms are also shown to improve the accuracy of these terms. Finally, simple preconditioning techniques are used in conjunction with iterative solution procedures to solve the resulting linear system efficiently. In order to handle the boundary integral singularities in the 3D formulation, the parent element- either a triangle or rectangle-is subdivided into a set of sub-triangles with a common vertex at the singularity. The contribution to the integral from each of the sub-triangles is computed using the Duffy transformation to remove the singularity. This method is shown to greatly facilitate t'pe self-term computation when the bases are of higher order. In addition, the sub-triangles can be further divided to achieve near arbitrary accuracy in the self-term computation. An efficient method for subdividing the parent element is presented. The accuracy obtained using higher order bases is compared to that obtained using lower order bases when the number

  2. Saturn's magnetosphere interaction with Titan for T5 encounter: 3D hybrid modeling. First results

    NASA Astrophysics Data System (ADS)

    Simpson, D. G.; Lipatov, A. S.; Sittler, E. C.; Hartle, R. E.; Cooper, J. F.

    2011-12-01

    Wave-particle interactions play a very important role in the plasma dynamics near Titan: mass loading, excitation of low-frequency waves and formation of the particle velocity distribution function (e.g. ring/shell-like distributions, etc.) The kinetic approach is important for estimating collision processes; e.g., charge exchange. In this report we discuss results of 3D hybrid modeling of the interaction between Saturn's magnetosphere and Titan's atmosphere/ionosphere. The modeling is based on recent analysis of the Cassini Plasma Spectrometer (CAPS) and the Cassini Ion, and Neutral Mass Spectrometer (INMS) measurements during the T5 flyby through Titan's ram-side and polar ionosphere [1,2]. Magnetic field data was used from the MAG instrument [3]. In our model the background ions (O+, H+), all pickup ions, and ionospheric ions are considered as a particles, whereas the electrons are described as a fluid. Inhomogeneous photoionization (in the dayside ionosphere), electron-impact ionization, and charge exchange are included in our model. The temperature of the background electrons and pickup electrons was also incorporated into the generalized Ohm's law. We also take into account collisions between ions and neutrals. In our hybrid simulations we use Chamberlain profiles for the exosphere's components. The moon is considered as a weakly conducting body. Special attention will be paid to comparing the modeling results with a single-fluid multi-species 3D MHD model [4], which included complex chemistry but does not produce finite gyroradius and kinetic effects. References [1] Sittler, E.C., et al., Energy Deposition Processes in Titan's Atmosphere and Its Induced Magnetosphere. In: Titan from Cassini-Huygens, Brown, R.H., Lebreton, J.P., Waite, J.H., Eds., Springer, (Dordrecht, Heidelberg, London, New York), pp. 393-455. [2] Agren, K., et al., On magnetosphere electron impact ionization and dynamics in Titan's ram-side and polar ionosphere -- a Cassini case study, Ann

  3. 3D assembly of semiconductor and metal nanocrystals: hybrid CdTe/Au structures with controlled content.

    PubMed

    Lesnyak, Vladimir; Wolf, André; Dubavik, Aliaksei; Borchardt, Lars; Voitekhovich, Sergei V; Gaponik, Nikolai; Kaskel, Stefan; Eychmüller, Alexander

    2011-08-31

    A 3D metal ion assisted assembly of nanoparticles has been developed. The approach relies on the efficient complexation of cadmium ions and 5-mercaptomethyltetrazole employed as the stabilizer of both colloidal CdTe and Au nanoparticles. It enables in a facile way the formation of hybrid metal-semiconductor 3D structures with controllable and tunable composition in aqueous media. By means of critical point drying, these assemblies form highly porous aerogels. The hybrid architectures obtained are characterized by electron microscopy, nitrogen adsorption, and optical spectroscopy methods.

  4. Go-ICP: A Globally Optimal Solution to 3D ICP Point-Set Registration.

    PubMed

    Yang, Jiaolong; Li, Hongdong; Campbell, Dylan; Jia, Yunde

    2016-11-01

    The Iterative Closest Point (ICP) algorithm is one of the most widely used methods for point-set registration. However, being based on local iterative optimization, ICP is known to be susceptible to local minima. Its performance critically relies on the quality of the initialization and only local optimality is guaranteed. This paper presents the first globally optimal algorithm, named Go-ICP, for Euclidean (rigid) registration of two 3D point-sets under the L2 error metric defined in ICP. The Go-ICP method is based on a branch-and-bound scheme that searches the entire 3D motion space SE(3). By exploiting the special structure of SE(3) geometry, we derive novel upper and lower bounds for the registration error function. Local ICP is integrated into the BnB scheme, which speeds up the new method while guaranteeing global optimality. We also discuss extensions, addressing the issue of outlier robustness. The evaluation demonstrates that the proposed method is able to produce reliable registration results regardless of the initialization. Go-ICP can be applied in scenarios where an optimal solution is desirable or where a good initialization is not always available.

  5. 3D Global Two-Fluid Simulations of Turbulence in LAPD

    NASA Astrophysics Data System (ADS)

    Fisher, Dustin; Rogers, Barrett; Ricci, Paolo

    2012-10-01

    3D global two-fluid simulations are presented in an ongoing effort to identify and understand the physics of instabilities that arise in the Large Plasma Device (LAPD) at UCLA's Basic Science Facility. The LAPD, with its wide range of tunable parameters and device configurations, is ideally suited for studying space and laboratory plasmas. Moreover, the highly detailed and reproducible measurements of the LAPD lend themselves amicably to comparisons with simulations. Ongoing modeling is done using a modified version of the Global Braginskii Solver (GBS) [1] that models the plasma from source to edge region in a fully 3D two-fluid code. The reduced Braginskii equations are solved on a field-aligned grid using a finite difference method and 4th order Runge-Kutta time stepping and are parallelized on Dartmouth's Discovery cluster. Recent progress has been made to account for the thermionic cathode emission of fast electrons at the source, the axial dependence of the plasma source, and it is now possible to vary the potential on the front and side walls. Preliminary results, seen from the density and temperature profiles, show that the low frequency Kelvin Helmholtz instability still dominates the turbulence in the device.[4pt] [1] B. Rogers and P. Ricci. Phys. Rev. Lett. 104:225002, 2010

  6. 3D Equilibrium Reconstruction with Improved Magnetic Diagnostics on the Compact Toroidal Hybrid

    NASA Astrophysics Data System (ADS)

    Ma, Xinxing; Hanson, James D.; Hartwell, Gregory J.; Knowlton, Stephen F.; Maurer, David A.

    2013-10-01

    Equilibrium reconstructions using the three-dimensional V3FIT code [ 1 ] have been performed for low density (low β) current carrying plasmas on the Compact Toroidal Hybrid (CTH), a torsatron in which the magnetic configuration can be strongly modified by an ohmically-driven plasma current. These reconstructions use 50 external magnetic diagnostic measurements, including segmented and full Rogowski coils, saddle loops, poloidal and radial magnetic pickup coils. Time dependent 3D reconstructions document the evolution of the plasma cross section and current profile, with calculated value of βθ much less than the plasma internal inductance, li. Reconstructions typically show the plasma to move outward in major radius and become less elongated in poloidal cross section with increasing plasma current. In plasmas with low vacuum transform (ιvac ~ 0 . 04), the plasma current profile peaks with li above 0 . 84 when the total transform is 1 / 2 , which typically leads disruption. With values of ιvac >= 0 . 1 , li remains low (~ 0 . 7), and the discharges no longer disrupt. This work is supported by the USDoE under grant DE-FG02-00ER54610.

  7. The plasma interaction of Enceladus: 3D hybrid simulations and comparison with Cassini MAG data

    NASA Astrophysics Data System (ADS)

    Kriegel, H.; Simon, S.; Müller, J.; Motschmann, U.; Saur, J.; Glassmeier, K.-H.; Dougherty, M. K.

    2009-12-01

    We study the interaction of Saturn's small, icy moon Enceladus and its plume with the corotating magnetospheric plasma by means of a 3D hybrid simulation model, which treats the ions as individual particles and the electrons as a massless, charge-neutralizing fluid. We analyze systematically how Enceladus' internal conductivity and plasma absorption at the surface as well as charge exchange and pick-up in the plume contribute to the overall structure of the interaction region. Furthermore, we provide a comparison of our simulation results to data obtained by the Cassini magnetometer instrument. The major findings of this study are: (1) the magnetic field diffuses through the solid body of Enceladus almost unaffected, whereas plasma absorption gives rise to a symmetric depletion wake downstream of the moon; (2) due to the small gyroradii of the newly generated plume ions, the pick-up tail possesses a 2D structure; (3) the magnetic field lines drape around the plume, which triggers an Alfvén wing system that dominates the structure of Enceladus' plasma environment. Inside the plume itself, a magnetic cavity is formed; (4) besides the reproduction of the key features of the observed magnetic field signatures, evidence for variability in the locations of the active jets and in the total gas content of the plume are shown.

  8. 3D phase unwrapping using global expected phase as a reference: application to MRI global shimming.

    PubMed

    Liu, Wentao; Tang, Xin; Ma, Yajun; Gao, Jia-Hong

    2013-07-01

    MRI phase data often suffers from phase wrapping (i.e., phase may be discontinuous by 2π jumps). Numerous MRI phase unwrapping strategies were developed in the past using a criterion based on phase information of local or neighboring voxels. In this study, an alternative and novel three dimensional phase unwrapping strategy is introduced. This method considers the global character of the phase distribution and utilizes continuous trigonometric functions to construct an expected phase map as an unwrapping reference, which is then used to guide the phase correction of every individual voxel. The original phase is estimated by analyzing the derivative of the wrapped phase image. Simulations of various phase wrapped situations were performed and this new method was also used for an in vivo application (i.e., MRI automatic global shimming). Both simulated and experimental results demonstrate that our proposed method is more reliable and robust than traditional algorithms at obtaining correct phase maps, especially in regions of low-signal and air cavities, such as the abdomen and pelvis.

  9. Extraordinary rate capability achieved by a 3D "skeleton/skin" carbon aerogel-polyaniline hybrid with vertically aligned pores.

    PubMed

    Liu, Mingkai; Li, Bomin; Zhou, Hang; Chen, Cong; Liu, Yuqing; Liu, Tianxi

    2017-03-02

    A 3D "skeleton/skin" carbon aerogel-polyaniline (CA-PANI) hybrid with vertically aligned pores exhibits an extraordinary rate capability. A high capacity retention (95%) has been achieved when the current density is increased from 1 to 100 A g(-1).

  10. Phosphonate-functionalized large pore 3-D cubic mesoporous (KIT-6) hybrid as highly efficient actinide extracting agent.

    PubMed

    Lebed, Pablo J; de Souza, Kellen; Bilodeau, François; Larivière, Dominic; Kleitz, Freddy

    2011-11-07

    A new type of radionuclide extraction material is reported based on phosphonate functionalities covalently anchored on the mesopore surface of 3-D cubic mesoporous silica (KIT-6). The easily prepared nanoporous hybrid shows largely superior performance in selective sorption of uranium and thorium as compared to the U/TEVA commercial resin and 2-D hexagonal SBA-15 equivalent.

  11. 3D Tomography of Ionospheric Perturbations Produced by Earthquakes Using Global Positioning System

    NASA Astrophysics Data System (ADS)

    Crespon, F.; Garcia, R.; Lognonné, P.; Murakami, M.

    2004-12-01

    The recent development of Global Positioning System led to establish dense regional networks of bistatic GPS receivers providing today a powerful ionospheric observing system. Now the ionosphere can be imaged by tomographic methods using GPS data. Therefore the ionospheric perturbations can be characterized by monitoring Total Electronic Content (TEC). These disturbances have multiple sources located adove and below ionospheric layers. The most known are the Travelling Ionospheric Disturbances (TID) produced by internal gravity waves. But some ionospheric disturbances are also due to infrasonic waves. We focus this study on ionospheric perturbations generated by infrasonic waves exited by seismic waves, resulting from the coupling between Earth and the atmosphere. We present a spectral analysis of TEC GPS data, the 3D tomographic method and its application to post-seismic perturbations. By removing background noise we are able to monitor acoustic post-seismic waves, generated by the rupture process and the seismic surface waves, that reach the ionosphere. Especially, we show the observations for the Denali earthquake of 3rd November 2002 and the Hokkaido earthquake of 25th September 2003 using respectively the Californian networks (SICGN) and the Japan network (GEONET). Both the horizontal and vertical propagation of the waves are vizualized in the 3D tomographic movies. The observed waves arrive with a timing and a propagation velocity coherent with expected waves and we purpose an interpretation in terms of infrasonic waves in the atmosphere, generated both near the epicenter and at further distance, at the level of the Rayleigh waves front. Finally we present the improvement of the 3D tomographic methods with the advent of the Galileo system and possible application in seismology.

  12. Analyzing Biological Performance of 3D-Printed, Cell-Impregnated Hybrid Constructs for Cartilage Tissue Engineering.

    PubMed

    Izadifar, Zohreh; Chang, Tuanjie; Kulyk, William; Chen, Xiongbiao; Eames, B Frank

    2016-03-01

    Three-dimensional (3D) bioprinting of hybrid constructs is a promising biofabrication method for cartilage tissue engineering because a synthetic polymer framework and cell-impregnated hydrogel provide structural and biological features of cartilage, respectively. During bioprinting, impregnated cells may be subjected to high temperatures (caused by the adjacent melted polymer) and process-induced mechanical forces, potentially compromising cell function. This study addresses these biofabrication issues, evaluating the heat distribution of printed polycaprolactone (PCL) strands and the rheological property and structural stability of alginate hydrogels at various temperatures and concentrations. The biocompatibility of parameters from these studies was tested by culturing 3D hybrid constructs bioprinted with primary cells from embryonic chick cartilage. During initial two-dimensional culture expansion of these primary cells, two morphologically and molecularly distinct cell populations ("rounded" and "fibroblastic") were isolated. The biological performance of each population was evaluated in 3D hybrid constructs separately. The cell viability, proliferation, and cartilage differentiation were observed at high levels in hybrid constructs of both cell populations, confirming the validity of these 3D bioprinting parameters for effective cartilage tissue engineering. Statistically significant performance variations were observed, however, between the rounded and fibroblastic cell populations. Molecular and morphological data support the notion that such performance differences may be attributed to the relative differentiation state of rounded versus fibroblastic cells (i.e., differentiated chondrocytes vs. chondroprogenitors, respectively), which is a relevant issue for cell-based tissue engineering strategies. Taken together, our study demonstrates that bioprinting 3D hybrid constructs of PCL and cell-impregnated alginate hydrogel is a promising approach for

  13. Mixed-hybrid and vertex-discontinuous-Galerkin finite element modeling of multiphase compositional flow on 3D unstructured grids

    NASA Astrophysics Data System (ADS)

    Moortgat, Joachim; Firoozabadi, Abbas

    2016-06-01

    Problems of interest in hydrogeology and hydrocarbon resources involve complex heterogeneous geological formations. Such domains are most accurately represented in reservoir simulations by unstructured computational grids. Finite element methods accurately describe flow on unstructured meshes with complex geometries, and their flexible formulation allows implementation on different grid types. In this work, we consider for the first time the challenging problem of fully compositional three-phase flow in 3D unstructured grids, discretized by any combination of tetrahedra, prisms, and hexahedra. We employ a mass conserving mixed hybrid finite element (MHFE) method to solve for the pressure and flux fields. The transport equations are approximated with a higher-order vertex-based discontinuous Galerkin (DG) discretization. We show that this approach outperforms a face-based implementation of the same polynomial order. These methods are well suited for heterogeneous and fractured reservoirs, because they provide globally continuous pressure and flux fields, while allowing for sharp discontinuities in compositions and saturations. The higher-order accuracy improves the modeling of strongly non-linear flow, such as gravitational and viscous fingering. We review the literature on unstructured reservoir simulation models, and present many examples that consider gravity depletion, water flooding, and gas injection in oil saturated reservoirs. We study convergence rates, mesh sensitivity, and demonstrate the wide applicability of our chosen finite element methods for challenging multiphase flow problems in geometrically complex subsurface media.

  14. 3D hybrid-porous carbon derived from carbonization of metal organic frameworks for high performance supercapacitors

    NASA Astrophysics Data System (ADS)

    Bao, Weizhai; Mondal, Anjon Kumar; Xu, Jing; Wang, Chengyin; Su, Dawei; Wang, Guoxiu

    2016-09-01

    We report a rational design and synthesis of 3D hybrid-porous carbon with a hierarchical pore architecture for high performance supercapacitors. It contains micropores (<2 nm diameter) and mesopores (2-4 nm), derived from carbonization of unique porous metal organic frameworks (MOFs). Owning to the synergistic effect of micropores and mesopores, the hybrid-porous carbon has exceptionally high ion-accessible surface area and low ion diffusion resistance, which is desired for supercapacitor applications. When applied as electrode materials in supercapacitors, 3D hybrid-porous carbon demonstrates a specific capacitance of 332 F g-1 at a constant charge/discharge current of 500 mA g-1. The supercapacitors can endure more than 10,000 cycles without degradation of capacitance.

  15. Local and Global 3-D Effects in the Magnetic Reconnection Experiment (MRX)

    NASA Astrophysics Data System (ADS)

    Dorfman, S.; Ji, H.; Yamada, M.; Oz, E.; Yoo, J.; Daughton, W.; Roytershteyn, V.

    2009-11-01

    One of the key open questions in Magnetic Reconnection is the nature of the mechanism that governs the reconnection rate in real astrophysical and laboratory systems. Comparisons between fully kinetic 2-D simulations of the Magnetic Reconnection Experiment (MRX) and experimental data show that the 2-D, collisionless expression for the electric field due to particle dynamics [1] does not match MRX data; related to this is a factor of 3-5 discrepancy in the layer width [2,3]. Adding collisions to the simulation leads to a broadening of the layer, but the level of collisionality present in MRX may not be high enough to resolve the discrepancy. Ongoing research on MRX explores the role of fluctuations and 3-D effects in the force balance. Significant toroidal asymmetries have been found, manifested by regions of high inductive electric field moving in the electron flow direction within the layer. Electromagnetic fluctuations in the lower hybrid frequency range [4] tend to occur in discharges with high local currents and a rapid local reconnection rate. The precise relation of these phenomena to fast reconnection is actively being investigated. [1] M. Hesse, et al., Phys. Plasmas, 6:1781 (1999). [2] Y. Ren, et al., Phys. Plasmas 15, 082113 (2008). [3] S. Dorfman, et al., Phys. Plasmas 15, 102107 (2008). [4] H. Ji, et al., Phys.Rev.Lett. 92 (2004) 115001. Supported by NDSEG, DOE, NASA, and NSF.

  16. 3D tract-specific local and global analysis of white matter integrity in Alzheimer's disease.

    PubMed

    Jin, Yan; Huang, Chao; Daianu, Madelaine; Zhan, Liang; Dennis, Emily L; Reid, Robert I; Jack, Clifford R; Zhu, Hongtu; Thompson, Paul M

    2017-03-01

    Alzheimer's disease (AD) is a chronic neurodegenerative disease characterized by progressive decline in memory and other aspects of cognitive function. Diffusion-weighted imaging (DWI) offers a non-invasive approach to delineate the effects of AD on white matter (WM) integrity. Previous studies calculated either some summary statistics over regions of interest (ROI analysis) or some statistics along mean skeleton lines (Tract Based Spatial Statistic [TBSS]), so they cannot quantify subtle local WM alterations along major tracts. Here, a comprehensive WM analysis framework to map disease effects on 3D tracts both locally and globally, based on a study of 200 subjects: 49 healthy elderly normal controls, 110 with mild cognitive impairment, and 41 AD patients has been presented. 18 major WM tracts were extracted with our automated clustering algorithm-autoMATE (automated Multi-Atlas Tract Extraction); we then extracted multiple DWI-derived parameters of WM integrity along the WM tracts across all subjects. A novel statistical functional analysis method-FADTTS (Functional Analysis for Diffusion Tensor Tract Statistics) was applied to quantify degenerative patterns along WM tracts across different stages of AD. Gradually increasing WM alterations were found in all tracts in successive stages of AD. Among all 18 WM tracts, the fornix was most adversely affected. Among all the parameters, mean diffusivity (MD) was the most sensitive to WM alterations in AD. This study provides a systematic workflow to examine WM integrity across automatically computed 3D tracts in AD and may be useful in studying other neurological and psychiatric disorders. Hum Brain Mapp 38:1191-1207, 2017. © 2016 Wiley Periodicals, Inc.

  17. 3D tract‐specific local and global analysis of white matter integrity in Alzheimer's disease

    PubMed Central

    Jin, Yan; Huang, Chao; Daianu, Madelaine; Zhan, Liang; Dennis, Emily L.; Reid, Robert I.; Jack, Clifford R.; Zhu, Hongtu

    2016-01-01

    Abstract Alzheimer's disease (AD) is a chronic neurodegenerative disease characterized by progressive decline in memory and other aspects of cognitive function. Diffusion‐weighted imaging (DWI) offers a non‐invasive approach to delineate the effects of AD on white matter (WM) integrity. Previous studies calculated either some summary statistics over regions of interest (ROI analysis) or some statistics along mean skeleton lines (Tract Based Spatial Statistic [TBSS]), so they cannot quantify subtle local WM alterations along major tracts. Here, a comprehensive WM analysis framework to map disease effects on 3D tracts both locally and globally, based on a study of 200 subjects: 49 healthy elderly normal controls, 110 with mild cognitive impairment, and 41 AD patients has been presented. 18 major WM tracts were extracted with our automated clustering algorithm—autoMATE (automated Multi‐Atlas Tract Extraction); we then extracted multiple DWI‐derived parameters of WM integrity along the WM tracts across all subjects. A novel statistical functional analysis method—FADTTS (Functional Analysis for Diffusion Tensor Tract Statistics) was applied to quantify degenerative patterns along WM tracts across different stages of AD. Gradually increasing WM alterations were found in all tracts in successive stages of AD. Among all 18 WM tracts, the fornix was most adversely affected. Among all the parameters, mean diffusivity (MD) was the most sensitive to WM alterations in AD. This study provides a systematic workflow to examine WM integrity across automatically computed 3D tracts in AD and may be useful in studying other neurological and psychiatric disorders. Hum Brain Mapp 38:1191–1207, 2017. © 2016 Wiley Periodicals, Inc. PMID:27883250

  18. Fabrication of chitosan-silver nanoparticle hybrid 3D porous structure as a SERS substrate for biomedical applications

    NASA Astrophysics Data System (ADS)

    Jung, Gyeong-Bok; Kim, Ji-Hye; Burm, Jin Sik; Park, Hun-Kuk

    2013-05-01

    We propose a simple, low-cost, large-area, and functional surface enhanced Raman scattering (SERS) substrate for biomedical applications. The SERS substrate with chitosan-silver nanoparticles (chitosan-Ag NPs) hybrid 3D porous structure was fabricated simply by a one-step method. The chitosan was used as a template for the Ag NPs deposition. SERS enhancement by the chitosan-Ag NPs substrate was experimentally verified using rhodamine B as an analyte. Thiolated single stranded DNA was also measured for atopic dermatitis genetic markers (chemokines CCL17) at a low concentration of 5 pM. We successfully designed a novel SERS substrate with silver nanoparticle hybridized 3D porous chitosan that has the potential to become a highly sensitive and selective tool for biomedical applications.

  19. Enhanced bone tissue regeneration using a 3D printed microstructure incorporated with a hybrid nano hydrogel.

    PubMed

    Heo, Dong Nyoung; Castro, Nathan J; Lee, Se-Jun; Noh, Hanaul; Zhu, Wei; Zhang, Lijie Grace

    2017-02-17

    Three-dimensional (3D) functional constructs with biomimetic mechanical and chemical properties are ideal for various regenerative medicine applications. These properties of 3D fabricated constructs mainly depend on the intrinsic characteristics of the materials and fabrication method. In this respect, the current use of hydrogels for musculoskeletal tissue repair is not ideal due to the lack of suitable mechanical properties, as well as the high biomimetic requirement for success. To overcome this limitation, we developed a novel functionalized hydrogel with bioactive gold nanoparticles (GNPs), reinforcing a 3D printed microstructure via fused deposition modeling (FDM) for bone tissue regeneration. We used biodegradable thermoplastic polylactic acid (PLA) as the 3D printed microstructure in combination with photo-curable gelatin hydrogels as the encapsulation matrix for the incorporation of cyclic RGD conjugated GNPs (RGNP), and investigated their mechanical properties. In addition, human adipose-derived stem cells (ADSCs) were encapsulated within the gelatin hydrogel and examined for viability, morphology, and osteogenic differentiation in vitro. The results showed that the stiffness of the composite hydrogel on reinforcing a 3D printed microstructure can be readily modulated to simulate the stiffness of the human mandibular condyle. ADSCs encapsulated in the composite structures remained viable within the hydrogel and showed excellent spreading on the 3D printed PLA microstructure. More importantly, osteogenic differentiation with incorporated RGNPs promoted significantly higher gene expression of osteogenic specific factors. Therefore, reinforced composite hydrogels are suitable for stem cell differentiation control and bone tissue regeneration.

  20. 3D Graphene-Foam-Reduced-Graphene-Oxide Hybrid Nested Hierarchical Networks for High-Performance Li-S Batteries.

    PubMed

    Hu, Guangjian; Xu, Chuan; Sun, Zhenhua; Wang, Shaogang; Cheng, Hui-Ming; Li, Feng; Ren, Wencai

    2016-02-24

    A 3D graphene-foam-reduced-graphene-oxide hybrid nested hierarchical network is synthesized to achieve high sulfur loading and content simultaneously, which solves the "double low" issues of Li-S batteries. The obtained Li-S cathodes show a high areal capacity two times larger than that of commercial lithium-ion batteries, and a good cycling performance comparable to those at low sulfur loading.

  1. A hand-held 3D laser scanning with global positioning system of subvoxel precision

    NASA Astrophysics Data System (ADS)

    Arias, Néstor; Meneses, Néstor; Meneses, Jaime; Gharbi, Tijani

    2011-01-01

    In this paper we propose a hand-held 3D laser scanner composed of an optical head device to extract 3D local surface information and a stereo vision system with subvoxel precision to measure the position and orientation of the 3D optical head. The optical head is manually scanned over the surface object by the operator. The orientation and position of the 3D optical head is determined by a phase-sensitive method using a 2D regular intensity pattern. This phase reference pattern is rigidly fixed to the optical head and allows their 3D location with subvoxel precision in the observation field of the stereo vision system. The 3D resolution achieved by the stereo vision system is about 33 microns at 1.8 m with an observation field of 60cm x 60cm.

  2. Global Existence and Asymptotic Behavior of Affine Motion of 3D Ideal Fluids Surrounded by Vacuum

    NASA Astrophysics Data System (ADS)

    Sideris, Thomas C.

    2017-03-01

    The 3D compressible and incompressible Euler equations with a physical vacuum free boundary condition and affine initial conditions reduce to a globally solvable Hamiltonian system of ordinary differential equations for the deformation gradient in {GL^+(3, R)} . The evolution of the fluid domain is described by a family of ellipsoids whose diameter grows at a rate proportional to time. Upon rescaling to a fixed diameter, the asymptotic limit of the fluid ellipsoid is determined by a positive semi-definite quadratic form of rank r = 1, 2, or 3, corresponding to the asymptotic degeneration of the ellipsoid along 3-r of its principal axes. In the compressible case, the asymptotic limit has rank r = 3, and asymptotic completeness holds, when the adiabatic index {γ} satisfies {4/3 < γ < 2} . The number of possible degeneracies, 3-r, increases with the value of the adiabatic index {γ} . In the incompressible case, affine motion reduces to geodesic flow in {SL(3, R)} with the Euclidean metric. For incompressible affine swirling flow, there is a structural instability. Generically, when the vorticity is nonzero, the domains degenerate along only one axis, but the physical vacuum boundary condition fails over a finite time interval. The rescaled fluid domains of irrotational motion can collapse along two axes.

  3. A hybrid kinetic hot ion PIC module for the M3D-C1 Code

    NASA Astrophysics Data System (ADS)

    Breslau, J. A.; Ferraro, N.; Jardin, S. C.; Kalyanaraman, K.

    2016-10-01

    Building on the success of the original M3D code with the addition of efficient high-order, high-continuity finite elements and a fully implicit time advance making use of cutting-edge numerical techniques, M3D-C1 has become a flagship code for realistic time-dependent 3D MHD and two-fluid calculations of the nonlinear evolution of macroinstabilities in tokamak plasmas. It is therefore highly desirable to introduce to M3D-C1 one of the most-used features of its predecessor: the option to use a drift-kinetic delta- f PIC model for a minority population of energetic ions (representing, e.g., beam ions or fusion alpha particles) coupled with the usual finite element advance of the bulk ion and electron fluids through its pressure tensor. We describe the implementation of a module for this purpose using high-order-of-accuracy numerical integration and carefully tuned to take advantage of state-of-the-art multicore processing elements. Verification results for a toroidal Alfvén eigenmode test problem will be presented, along with a demonstration of favorable parallel scaling to large numbers of supercomputer nodes.

  4. Extending the global coverage of Slab1.0 3D subduction zone models

    NASA Astrophysics Data System (ADS)

    Seidman, L.; Hayes, G. P.

    2013-12-01

    Slab1.0 is a three-dimensional model of subduction zone geometries that covers approximately 85% of global slabs by area. It is built from an automated interpolation of a combined dataset made up from subduction-related earthquakes, moment tensors, interpretations of active source seismic data, and models of bathymetry and sediment thickness. Those subduction zones that are missing from the model are difficult to characterize with this automated approach because of sparse teleseismically located, interplate seismicity (e.g., Cascadia, Hikurangi), complex geometry (e.g., Halmahera, southern Philippine Sea), or some combination of these issues (e.g., Caribbean). Here we attempt to solve this problem with a straightforward modification of the Slab1.0 approach. Instead of constructing a series of automated spline fits to our geophysical data in two-dimensional cross sections, we produce hand-contoured two-dimensional fits; under the assumption that where seismicity is sparse or geometry complex, a human guided by tectonic knowledge can produce a better fit to geometry than can a computer algorithm. These manual 2D sections are then interpolated into a 3D surface in the same way automated 2D fits are processed for Slab1.0. Following this approach, we produce models for slabs in the Caribbean, the Makran, the Manila Trench, the Halmahera Plate, and the Hellenic Arc. We also address regions of current models (e.g., Peru) that were poorly characterized by the original automated approach. These new models thus provide valuable information on subduction zone structure from the trench and into the mantle in regions previously missing from Slab1.0, and help to make existing models more accurate, and thus more useful, than was previously possible. In turn, the models can be used to better characterize associated seismic hazards.

  5. The anthropogenic influence on Iron deposition over the oceans: a 3-D global modeling

    NASA Astrophysics Data System (ADS)

    Myriokefalitakis, Stelios; Mihalopoulos, Nikos; Baker, Alex; Kanakidou, Maria

    2014-05-01

    Iron (Fe) deposition over oceans is directly linked to the marine biological productivity and consequently to atmospheric CO2 concentrations. Experimental and modeling results support that both inorganic (sulphate, ammonium and nitrate) and organic (e.g. oxalate) ligands can increase the Fe mobilization. Mineral dust deposition is considered as the most important supply of bioavailable Fe in the oceans. Although, due to the low soil soluble iron fractions, atmospheric processes which are also related to anthropogenic emissions, can convert iron to more soluble forms in the atmosphere. Recent studies also support that anthropogenic emissions of Fe from combustion sources also significantly contribute to the dissolved Fe atmospheric pool. The evaluation of the impact of humans on atmospheric soluble or bioavailable Fe deposition remains challenging, since Fe mobilization due to changes in anthropogenic emissions is largely uncertain. In the present study, the global atmospheric Fe cycle is parameterized in the 3-D chemical transport global model TM4-ECPL and the model is used to calculate the Fe deposition over the oceans. The model considers explicitly organic, sulfur and nitrogen gas-phase chemistry, aqueous-phase organic chemistry, including oxalate and all major aerosol constituents. TM4-ECPL simulates the organic and inorganic ligand-promoted mineral Fe dissolution and also aqueous-phase photochemical reactions between different forms of Fe (III/II). Primary emissions of Fe associated with dust and soluble Fe from combustion processes as well as atmospheric processing of the emitted Fe is taken into account in the model Sensitivity simulations are performed to study the impact of anthropogenic emissions on Fe deposition. For this preindustrial, present and future emission scenarios are used in the model in order to examine the response of chemical composition of iron-containing aerosols to environmental changes. The release of soluble iron associated with

  6. Strontium eluting graphene hybrid nanoparticles augment osteogenesis in a 3D tissue scaffold.

    PubMed

    Kumar, Sachin; Chatterjee, Kaushik

    2015-02-07

    The objective of this work was to prepare hybrid nanoparticles of graphene sheets decorated with strontium metallic nanoparticles and demonstrate their advantages in bone tissue engineering. Strontium-decorated reduced graphene oxide (RGO_Sr) hybrid nanoparticles were synthesized by the facile reduction of graphene oxide and strontium nitrate. X-ray diffraction, transmission electron microscopy, and atomic force microscopy revealed that the hybrid particles were composed of RGO sheets decorated with 200-300 nm metallic strontium particles. Thermal gravimetric analysis further confirmed the composition of the hybrid particles as 22 wt% of strontium. Macroporous tissue scaffolds were prepared by incorporating RGO_Sr particles in poly(ε-caprolactone) (PCL). The PCL/RGO_Sr scaffolds were found to elute strontium ions in aqueous medium. Osteoblast proliferation and differentiation was significantly higher in the PCL scaffolds containing the RGO_Sr particles in contrast to neat PCL and PCL/RGO scaffolds. The increased biological activity can be attributed to the release of strontium ions from the hybrid nanoparticles. This study demonstrates that composites prepared using hybrid nanoparticles that elute strontium ions can be used to prepare multifunctional scaffolds with good mechanical and osteoinductive properties. These findings have important implications for designing the next generation of biomaterials for use in tissue regeneration.

  7. Self-assembly of polydimethylsiloxane structures from 2D to 3D for bio-hybrid actuation.

    PubMed

    Vannozzi, L; Ricotti, L; Cianchetti, M; Bearzi, C; Gargioli, C; Rizzi, R; Dario, P; Menciassi, A

    2015-08-20

    This work aims to demonstrate the feasibility of a novel approach for the development of 3D self-assembled polydimethylsiloxane structures, to be used as engineered flexible matrices for bio-hybrid actuation. We described the fabrication of engineered bilayers, organized in a 3D architecture by means of a stress-induced rolling membrane technique. Such structures were provided with ad hoc surface topographies, for both cell alignment and cell survival after membrane rolling. We reported the results of advanced finite element model simulations, predicting the system behavior in terms of overall contraction, induced by the contractile activity of muscle cells seeded on the membrane. Then, we tested in vitro the structure with primary cardiomyocytes to evaluate the real bio-actuator contraction, thus validating the simulation results. At a later stage, we provided the samples with a stable fibronectin coating, by covalently binding the protein on the polymer surface, thus enabling long-term cultures with C2C12 skeletal muscle cells, a more controllable cell type. These tests revealed cell viability and alignment on the rolled structures, but also the ability of cells to differentiate and to form multinucleated and oriented myotubes on the polymer surface, also supported by a fibroblast feeder layer. Our results highlighted the possibility of developing 3D rolled PDMS structures, characterized by different mechanical properties, as novel bio-hybrid actuators.

  8. Uncertainty analysis in 3D global models: Aerosol representation in MOZART-4

    NASA Astrophysics Data System (ADS)

    Gasore, J.; Prinn, R. G.

    2012-12-01

    The Probabilistic Collocation Method (PCM) has been proven to be an efficient general method of uncertainty analysis in atmospheric models (Tatang et al 1997, Cohen&Prinn 2011). However, its application has been mainly limited to urban- and regional-scale models and chemical source-sink models, because of the drastic increase in computational cost when the dimension of uncertain parameters increases. Moreover, the high-dimensional output of global models has to be reduced to allow a computationally reasonable number of polynomials to be generated. This dimensional reduction has been mainly achieved by grouping the model grids into a few regions based on prior knowledge and expectations; urban versus rural for instance. As the model output is used to estimate the coefficients of the polynomial chaos expansion (PCE), the arbitrariness in the regional aggregation can generate problems in estimating uncertainties. To address these issues in a complex model, we apply the probabilistic collocation method of uncertainty analysis to the aerosol representation in MOZART-4, which is a 3D global chemical transport model (Emmons et al., 2010). Thereafter, we deterministically delineate the model output surface into regions of homogeneous response using the method of Principal Component Analysis. This allows the quantification of the uncertainty associated with the dimensional reduction. Because only a bulk mass is calculated online in Mozart-4, a lognormal number distribution is assumed with a priori fixed scale and location parameters, to calculate the surface area for heterogeneous reactions involving tropospheric oxidants. We have applied the PCM to the six parameters of the lognormal number distributions of Black Carbon, Organic Carbon and Sulfate. We have carried out a Monte-Carlo sampling from the probability density functions of the six uncertain parameters, using the reduced PCE model. The global mean concentration of major tropospheric oxidants did not show a

  9. A hybrid experimental-numerical technique for determining 3D velocity fields from planar 2D PIV data

    NASA Astrophysics Data System (ADS)

    Eden, A.; Sigurdson, M.; Mezić, I.; Meinhart, C. D.

    2016-09-01

    Knowledge of 3D, three component velocity fields is central to the understanding and development of effective microfluidic devices for lab-on-chip mixing applications. In this paper we present a hybrid experimental-numerical method for the generation of 3D flow information from 2D particle image velocimetry (PIV) experimental data and finite element simulations of an alternating current electrothermal (ACET) micromixer. A numerical least-squares optimization algorithm is applied to a theory-based 3D multiphysics simulation in conjunction with 2D PIV data to generate an improved estimation of the steady state velocity field. This 3D velocity field can be used to assess mixing phenomena more accurately than would be possible through simulation alone. Our technique can also be used to estimate uncertain quantities in experimental situations by fitting the gathered field data to a simulated physical model. The optimization algorithm reduced the root-mean-squared difference between the experimental and simulated velocity fields in the target region by more than a factor of 4, resulting in an average error less than 12% of the average velocity magnitude.

  10. 3D printing of high-resolution PLA-based structures by hybrid electrohydrodynamic and fused deposition modeling techniques

    NASA Astrophysics Data System (ADS)

    Zhang, Bin; Seong, Baekhoon; Nguyen, VuDat; Byun, Doyoung

    2016-02-01

    Recently, the three-dimensional (3D) printing technique has received much attention for shape forming and manufacturing. The fused deposition modeling (FDM) printer is one of the various 3D printers available and has become widely used due to its simplicity, low-cost, and easy operation. However, the FDM technique has a limitation whereby its patterning resolution is too low at around 200 μm. In this paper, we first present a hybrid mechanism of electrohydrodynamic jet printing with the FDM technique, which we name E-FDM. We then develop a novel high-resolution 3D printer based on the E-FDM process. To determine the optimal condition for structuring, we also investigated the effect of several printing parameters, such as temperature, applied voltage, working height, printing speed, flow-rate, and acceleration on the patterning results. This method was capable of fabricating both high resolution 2D and 3D structures with the use of polylactic acid (PLA). PLA has been used to fabricate scaffold structures for tissue engineering, which has different hierarchical structure sizes. The fabrication speed was up to 40 mm/s and the pattern resolution could be improved to 10 μm.

  11. Ship-in-a-bottle integration by hybrid femtosecond laser technology for fabrication of true 3D biochips

    NASA Astrophysics Data System (ADS)

    Sima, Felix; Wu, Dong; Xu, Jian; Midorikawa, Katsumi; Sugioka, Koji

    2015-03-01

    We propose herein the "ship-in-a-bottle" integration of three-dimensional (3D) polymeric sinusoidal ridges inside photosensitive glass microfluidic channel by a hybrid subtractive - additive femtosecond laser processing method. It consists of Femtosecond Laser Assisted Wet Etching (FLAE) of a photosensitive Foturan glass followed by Two-Photon Polymerization (TPP) of a SU-8 negative epoxy-resin. Both subtractive and additive processes are carried out using the same set-up with the change of laser focusing objective only. A 522 nm wavelength of the second harmonic generation from an amplified femtosecond Yb-fiber laser (FCPA µJewel D-400, IMRA America, 1045 nm; pulse width 360 fs, repetition rate 200 kHz) was employed for irradiation. The new method allows lowering the size limit of 3D objects created inside channels to smaller details down to the dimensions of a cell, and improve the structure stability. Sinusoidal periodic patterns and ridges are of great use as base scaffolds for building up new structures on their top or for modulating cell migration, guidance and orientation while created interspaces can be exploited for microfluidic applications. The glass microchannel offers robustness and appropriate dynamic flow conditions for cellular studies while the integrated patterns are reducing the size of structure to the level of cells responsiveness. Taking advantage of the ability to directly fabricate 3D complex shapes, both glass channels and polymeric integrated patterns enable us to 3D spatially design biochips for specific applications.

  12. Global Effects of the Interplanetary Shock Propagation through the Earth's Inner Magnetosphere: 3D Hybrid Kinetic ModelingA.S. Lipatov {1}, D.G. Sibeck {2}{1} GPHI UMBC/NASA GSFC, Greenbelt, MD 20771, USA {2} NASA GSFC, Greenbelt, MD 20771, USA

    NASA Astrophysics Data System (ADS)

    Lipatov, A. S.; Sibeck, D. G.

    2015-12-01

    We use a new hybrid kinetic model to simulate the response of ring current, outer radiation belt, and plasmasphere particle populations to impulsive interplanetary shocks. Since particle distributions attending the interplanetary shock waves and in the ring current and radiation belts are non-Maxwellian, wave-particle interactions play a crucial role in energy transport within the inner magnetosphere. Finite gyroradius effects become important in mass loading the shock waves with the background plasma in the presence of higher energy ring current and radiation belt ions and electrons. Initial results show that the shock causes strong deformations in the global structure of the ring current, radiation belt, and plasmasphere. The ion velocity distribution functions at the shock front, in the ring current, and in the radiation belt help us to determine energy transport through the Earth's inner magnetosphere. We compare our predictions with THEMIS and Van Allen Probes spacecraft observations.

  13. Global strong solution to the 3D incompressible magnetohydrodynamic system in the scaling invariant Besov-Sobolev-type spaces

    NASA Astrophysics Data System (ADS)

    Ma, Haitao; Zhai, Xiaoping; Yan, Wei; Li, Yongsheng

    2017-02-01

    In this paper, we study the global well posedness of the 3D incompressible magnetohydrodynamic system with horizontal dissipation and horizontal magnetic diffusion in the scaling invariant Besov-Sobolev-type spaces. We first get a unique global solution to this system with small initial data by the classical Friedrich's regularization method. Then using a weighted Chemin-Lerner-type norm, we prove the system also can generate a global solution if the horizontal components of the initial data are small enough compared to the vertical components. In particular, our results imply the global large solutions with highly oscillating initial data.

  14. Novel fabrication technique of hybrid structure lens array for 3D images

    NASA Astrophysics Data System (ADS)

    Lee, Junsik; Kim, Junoh; Kim, Cheoljoong; Shin, Dooseub; Koo, Gyohyun; Won, Yong Hyub

    2016-03-01

    Tunable liquid lens arrays can produce three dimensional images by using electrowetting principle that alters surface tensions by applying voltage. This method has advantages of fast response time and low power consumption. However, it is challenging to fabricate a high fill factor liquid lens array and operate three dimensional images which demand high diopter. This study describes a hybrid structure lens array which has not only a liquid lens array but a solid lens array. A concave-shape lens array is unavoidable when using only the liquid lens array and some voltages are needed to make the lens flat. By placing the solid lens array on the liquid lens array, initial diopter can be positive. To fabricate the hybrid structure lens array, a conventional lithographic process in semiconductor manufacturing is needed. A negative photoresist SU-8 was used as chamber master molds. PDMS and UV adhesive replica molding are done sequentially. Two immiscible liquids, DI water and dodecane, are injected in the fabricated chamber, followed by sealing. The fabricated structure has a 20 by 20 pattern of cylindrical shaped circle array and the aperture size of each lens is 1mm. The thickness of the overall hybrid structure is about 2.8mm. Hybrid structure lens array has many advantages. Solid lens array has almost 100% fill factor and allow high efficiency. Diopter can be increased by more than 200 and negative diopter can be shifted to the positive region. This experiment showed several properties of the hybrid structure and demonstrated its superiority.

  15. A novel 3D sandwich structure of hybrid graphite nanosheets and silver nanowires as fillers for improved thermal conductivity

    NASA Astrophysics Data System (ADS)

    Zhuang, Xiao; Zhou, Yongcun; Liu, Feng

    2017-01-01

    We explored a novel 3D sandwich structure of fillers in the polymer matrix to enhance thermal conductivity. A variety of fillers in the polymer matrix play a significant role in the physical properties of the composite. Fillers containing particle and line structures are popular, and enhance the thermal and electrical conductivities. Therefore, filler-based matrix network improves conductivity. We propose a sandwich structure consisting of hybrid graphite nanosheets (two dimensions), and silver nanowires (AgNWs) (one dimension), to create a 3D sandwich structure of polyimide matrix with improved thermal conductivity. Surface treatment of graphite and silver nanowires were conducted to reduce the dielectric constant of the composite. We designed the filler of 20 wt% resulting in a high thermal conductivity of 3.21 W m‑1 K‑1 with 15% C@SiO2 and 5% AgNWs@SiO2 filler loading. The novel combination and structure markedly enhanced the thermal conductivity of the composite.

  16. Si-gold-glass hybrid wafer bond for 3D-MEMS and wafer level packaging

    NASA Astrophysics Data System (ADS)

    Reddy, Jayaprakash; Pratap, Rudra

    2017-01-01

    We report a relatively low temperature (<400 °C) hybrid wafer bonding process that results in the simultaneous anodic and eutectic bonding in different predetermined regions of the wafer. This hybrid bonding process has potential applications in CMOS-MEMS device integration and wafer level packaging. We demonstrate the process by realizing a simple MEMS cantilever beam and a complex MEMS gyroscope structure. These structures are characterized for ohmic contact and electromechanical response to verify the electrical interconnect and the mechanical strength of the structure at the bond interface.

  17. Rui Liao's work on patient-specific 3-D model guidance for interventional and hybrid-operating-room applications.

    PubMed

    Liao, Rui

    2011-06-28

    Compared to surgery, interventional and hybrid-operating-room (OR) approaches diagnose or treat pathology with the most minimally invasive techniques possible. By minimizing the physical trauma to the patient, peripheral or hybrid approaches can reduce infection rates and recovery time as well as shorten hospital stays. Minimally invasive approaches therefore are the trend and often the preferred choice, and may even be the only option for the patients associated with high surgery risks. Common interventional imaging modalities include 2-D X-ray fluoroscopy and ultrasound. However, fluoroscopic images do not display the anatomic structures without a contrast agent, which on the other hand, needs to be minimized for patients' safety. Ultrasound images suffer from relatively low image quality and tissue contrast problems. To augment the doctor's view of the patient's anatomy and help doctors navigate the devices to the targeted area with more confidence and a higher accuracy, high-resolution pre-operative volumetric data such as computed tomography and/or magnetic resonance can be fused with intra-operative 2-D images during interventions. A seamless workflow and accurate 2-D/3-D registration as well as cardiac and/or respiratory motion compensation are the key components for a successful image guidance system using a patient-specific 3-D model. Dr. Liao's research has been focused on developing methods and systems of 3-D model guidance for various interventions and hybrid-OR applications. Dr. Liao's work has led to several Siemens products with high clinical and/or market impact and a good number of scientific publications in leading journals/conferences on medical imaging.

  18. A global 3-D CTM evaluation of black carbon in the Tibetan Plateau

    NASA Astrophysics Data System (ADS)

    He, C.; Li, Q. B.; Liou, K. N.; Zhang, J.; Qi, L.; Mao, Y.; Gao, M.; Lu, Z.; Streets, D. G.; Zhang, Q.; Sarin, M. M.; Ram, K.

    2014-07-01

    We systematically evaluate the black carbon (BC) simulations for 2006 over the Tibetan Plateau by a global 3-D chemical transport model (CTM) (GEOS-Chem) driven by GEOS-5 assimilated meteorological fields, using in situ measurements of BC in surface air, BC in snow, and BC absorption aerosol optical depth (AAOD). Using improved anthropogenic BC emission inventories for Asia that account for rapid technology renewal and energy consumption growth (Zhang et al., 2009; Lu et al., 2011) and improved global biomass burning emission inventories that account for small fires (van der Werf et al., 2010; Randerson et al., 2012), we find that model results of both BC in surface air and in snow are statistically in good agreement with observations (biases < 15%) away from urban centers. Model results capture the seasonal variations of the surface BC concentrations at rural sites in the Indo-Gangetic Plain, but the observed elevated values in winter are absent. Modeled surface-BC concentrations are within a factor of 2 of the observations at remote sites. Part of the discrepancy is explained by the deficiencies of the meteorological fields over the complex Tibetan terrain. We find that BC concentrations in snow computed from modeled BC deposition and GEOS-5 precipitation are spatiotemporally consistent with observations (r = 0.85). The computed BC concentrations in snow are a factor of 2-4 higher than the observations at several Himalayan sites because of excessive BC deposition. The BC concentrations in snow are biased low by a factor of 2 in the central plateau, which we attribute to the absence of snow aging in the CTM and strong local emissions unaccounted for in the emission inventories. Modeled BC AAOD is more than a factor of 2 lower than observations at most sites, particularly to the northwest of the plateau and along the southern slopes of the Himalayas in winter and spring, which is attributable in large part to underestimated emissions and the assumption of external

  19. Hybrid nickel manganese oxide nanosheet-3D metallic dendrite percolation network electrodes for high-rate electrochemical energy storage.

    PubMed

    Nguyen, Tuyen; Eugénio, Sónia; Boudard, Michel; Rapenne, Laetitia; Carmezim, M João; Silva, Teresa M; Montemor, M Fátima

    2015-08-07

    This work reports the fabrication, by electrodeposition and post-thermal annealing, of hybrid electrodes for high rate electrochemical energy storage composed of nickel manganese oxide (Ni0.86Mn0.14O) nanosheets over 3D open porous dendritic NiCu foams. The hybrid electrodes are made of two different percolation networks of nanosheets and dendrites, and exhibit a specific capacitance value of 848 F g(-1) at 1 A g(-1). The electrochemical tests revealed that the electrodes display an excellent rate capability, characterized by capacitance retention of approximately 83% when the applied current density increases from 1 A g(-1) to 20 A g(-1). The electrodes also evidenced high charge-discharge cycling stability, which attained 103% after 1000 cycles.

  20. A Hybrid Geophysical Fluid Dynamics and Fully 3D Fluid Dynamics Approach to Simulate Multiphysics Coastal Flows

    NASA Astrophysics Data System (ADS)

    Tang, H.; Qu, K.

    2014-12-01

    A hybrid method that couples a geophysical fluid dynamics model to a fully 3D fluid dynamics model is the most feasible and promising approach to simulate coastal ocean flow phenomena that involve multiple types of physics spanning a vast range of temporal and spatial scales. We propose such a hybrid method that couples the Finite Volume Coastal Ocean Model (FVCOM) with the Solver for Incompressible Flow on Overset Meshes (SIFOM); the former is used to simulate large-scale estuary flows, and the latter is employed to capture small-scale local processes. The coupling involves distinct governing equations, different numerical algorithms, and dissimilar grids, and it is two-way and realized using the Schwartz alternative iteration. In this presentation, the proposed method will be outlined, and a few applications that are newly produced by it but cannot be handled by other conventional approaches will be presented.

  1. Advanced 3D electromagnetic and particle-in-cell modeling on structured/unstructured hybrid grids

    SciTech Connect

    Seidel, D.B.; Pasik, M.F.; Kiefer, M.L.; Riley, D.J.; Turner, C.D.

    1998-01-01

    New techniques have been recently developed that allow unstructured, free meshes to be embedded into standard 3-dimensional, rectilinear, finite-difference time-domain grids. The resulting hybrid-grid modeling capability allows the higher resolution and fidelity of modeling afforded by free meshes to be combined with the simplicity and efficiency of rectilinear techniques. Integration of these new methods into the full-featured, general-purpose QUICKSILVER electromagnetic, Particle-In-Cell (PIC) code provides new modeling capability for a wide variety of electromagnetic and plasma physics problems. To completely exploit the integration of this technology into QUICKSILVER for applications requiring the self-consistent treatment of charged particles, this project has extended existing PIC methods for operation on these hybrid unstructured/rectilinear meshes. Several technical issues had to be addressed in order to accomplish this goal, including the location of particles on the unstructured mesh, adequate conservation of charge, and the proper handling of particles in the transition region between structured and unstructured portions of the hybrid grid.

  2. 3D hybrid simulations of the plasma penetration across a magnetic field

    NASA Astrophysics Data System (ADS)

    Omelchenko, Yuri

    2016-10-01

    The expansion of hot dense plasmas across ambient magnetic fields in physical systems with spatial scales comparable to the ion gyro and inertial lengths is of great interest to space physics and fusion. This work presents results from recent three-dimensional hybrid simulations (kinetic ions, fluid electrons) of experiments at the LAPD and Nevada Terawatt Facility where short-pulse lasers are used to ablate solid targets to produce plasmas that expand across external magnetic fields. The first simulation recreates flutelike density striations observed at the leading edge of the carbon plasma and predicts an early destruction of the magnetic cavity in agreement with experimental evidence. In the second simulation the plasma contains protons and carbon ions produced during the ablation of a polyethylene target. A mechanism is demonstrated that allows protons to penetrate the magnetic field in the form of a collimated flow while the carbon ion component forms a supporting magnetic structure. The role of ion kinetic and Hall effects in creating an electric field responsible for plasma transport is discussed and results are compared to experimental data. The hybrid simulations are performed with a massively parallel hybrid code, HYPERS that advances fields and particles asynchronously on time scales determined by local physical and geometric properties. Supported by US DOE Award DE-SC0012345.

  3. 3D carbon/cobalt-nickel mixed-oxide hybrid nanostructured arrays for asymmetric supercapacitors.

    PubMed

    Zhu, Jianhui; Jiang, Jian; Sun, Zhipeng; Luo, Jingshan; Fan, Zhanxi; Huang, Xintang; Zhang, Hua; Yu, Ting

    2014-07-23

    The electrochemical performance of supercapacitors relies not only on the exploitation of high-capacity active materials, but also on the rational design of superior electrode architectures. Herein, a novel supercapacitor electrode comprising 3D hierarchical mixed-oxide nanostructured arrays (NAs) of C/CoNi3 O4 is reported. The network-like C/CoNi3 O4 NAs exhibit a relatively high specific surface area; it is fabricated from ultra-robust Co-Ni hydroxide carbonate precursors through glucose-coating and calcination processes. Thanks to their interconnected three-dimensionally arrayed architecture and mesoporous nature, the C/CoNi3 O4 NA electrode exhibits a large specific capacitance of 1299 F/g and a superior rate performance, demonstrating 78% capacity retention even when the discharge current jumps by 100 times. An optimized asymmetric supercapacitor with the C/CoNi3 O4 NAs as the positive electrode is fabricated. This asymmetric supercapacitor can reversibly cycle at a high potential of 1.8 V, showing excellent cycling durability and also enabling a remarkable power density of ∼13 kW/kg with a high energy density of ∼19.2 W·h/kg. Two such supercapacitors linked in series can simultaneously power four distinct light-emitting diode indicators; they can also drive the motor of remote-controlled model planes. This work not only presents the potential of C/CoNi3 O4 NAs in thin-film supercapacitor applications, but it also demonstrates the superiority of electrodes with such a 3D hierarchical architecture.

  4. Left-ventricle segmentation in real-time 3D echocardiography using a hybrid active shape model and optimal graph search approach

    NASA Astrophysics Data System (ADS)

    Zhang, Honghai; Abiose, Ademola K.; Campbell, Dwayne N.; Sonka, Milan; Martins, James B.; Wahle, Andreas

    2010-03-01

    Quantitative analysis of the left ventricular shape and motion patterns associated with left ventricular mechanical dyssynchrony (LVMD) is essential for diagnosis and treatment planning in congestive heart failure. Real-time 3D echocardiography (RT3DE) used for LVMD analysis is frequently limited by heavy speckle noise or partially incomplete data, thus a segmentation method utilizing learned global shape knowledge is beneficial. In this study, the endocardial surface of the left ventricle (LV) is segmented using a hybrid approach combining active shape model (ASM) with optimal graph search. The latter is used to achieve landmark refinement in the ASM framework. Optimal graph search translates the 3D segmentation into the detection of a minimum-cost closed set in a graph and can produce a globally optimal result. Various information-gradient, intensity distributions, and regional-property terms-are used to define the costs for the graph search. The developed method was tested on 44 RT3DE datasets acquired from 26 LVMD patients. The segmentation accuracy was assessed by surface positioning error and volume overlap measured for the whole LV as well as 16 standard LV regions. The segmentation produced very good results that were not achievable using ASM or graph search alone.

  5. Characterizing microscale aluminum composite layer properties on silicon solar cells with hybrid 3D scanning force measurements.

    PubMed

    Bae, Sung-Kuk; Choi, Beomjoon; Chung, Haseung; Shin, Seungwon; Song, Hee-eun; Seo, Jung Hwan

    2016-03-07

    This article presents a novel technique to estimate the mechanical properties of the aluminum composite layer on silicon solar cells by using a hybrid 3-dimensional laser scanning force measurement (3-D LSFM) system. The 3-D LSFM system measures the material properties of sub-layers constituting a solar cell. This measurement is critical for realizing high-efficient ultra-thin solar cells. The screen-printed aluminum layer, which significantly affects the bowing phenomenon, is separated from the complete solar cell by removing the silicon (Si) layer with deep reactive ion etching. An elastic modulus of ~15.1 GPa and a yield strength of ~35.0 MPa for the aluminum (Al) composite layer were obtained by the 3-D LSFM system. In experiments performed for 6-inch Si solar cells, the bowing distances decreased from 12.02 to 1.18 mm while the Si layer thicknesses increased from 90 to 190 μm. These results are in excellent agreement with the theoretical predictions for ultra-thin Si thickness (90 μm) based on the obtained Al composite layer properties.

  6. Characterizing microscale aluminum composite layer properties on silicon solar cells with hybrid 3D scanning force measurements

    NASA Astrophysics Data System (ADS)

    Bae, Sung-Kuk; Choi, Beomjoon; Chung, Haseung; Shin, Seungwon; Song, Hee-Eun; Seo, Jung Hwan

    2016-03-01

    This article presents a novel technique to estimate the mechanical properties of the aluminum composite layer on silicon solar cells by using a hybrid 3-dimensional laser scanning force measurement (3-D LSFM) system. The 3-D LSFM system measures the material properties of sub-layers constituting a solar cell. This measurement is critical for realizing high-efficient ultra-thin solar cells. The screen-printed aluminum layer, which significantly affects the bowing phenomenon, is separated from the complete solar cell by removing the silicon (Si) layer with deep reactive ion etching. An elastic modulus of ~15.1 GPa and a yield strength of ~35.0 MPa for the aluminum (Al) composite layer were obtained by the 3-D LSFM system. In experiments performed for 6-inch Si solar cells, the bowing distances decreased from 12.02 to 1.18 mm while the Si layer thicknesses increased from 90 to 190 μm. These results are in excellent agreement with the theoretical predictions for ultra-thin Si thickness (90 μm) based on the obtained Al composite layer properties.

  7. Characterizing microscale aluminum composite layer properties on silicon solar cells with hybrid 3D scanning force measurements

    PubMed Central

    Bae, Sung-Kuk; Choi, Beomjoon; Chung, Haseung; Shin, Seungwon; Song, Hee-eun; Seo, Jung Hwan

    2016-01-01

    This article presents a novel technique to estimate the mechanical properties of the aluminum composite layer on silicon solar cells by using a hybrid 3-dimensional laser scanning force measurement (3-D LSFM) system. The 3-D LSFM system measures the material properties of sub-layers constituting a solar cell. This measurement is critical for realizing high-efficient ultra-thin solar cells. The screen-printed aluminum layer, which significantly affects the bowing phenomenon, is separated from the complete solar cell by removing the silicon (Si) layer with deep reactive ion etching. An elastic modulus of ~15.1 GPa and a yield strength of ~35.0 MPa for the aluminum (Al) composite layer were obtained by the 3-D LSFM system. In experiments performed for 6-inch Si solar cells, the bowing distances decreased from 12.02 to 1.18 mm while the Si layer thicknesses increased from 90 to 190 μm. These results are in excellent agreement with the theoretical predictions for ultra-thin Si thickness (90 μm) based on the obtained Al composite layer properties. PMID:26948248

  8. Electrochemically formed 3D hierarchical thin films of cobalt-manganese (Co-Mn) hexacyanoferrate hybrids for electrochemical applications

    NASA Astrophysics Data System (ADS)

    Alam Venugopal, Narendra Kumar; Joseph, James

    2016-02-01

    Here we report the feasibility of forming 3D nanostructured hexacyanoferates of Cobalt and Manganese (Co-MnHCF) on GC surface by a facile electrochemical method. This 3D architecture on glassy carbon electrode characterised systematically by voltammetry and other physical characterisation techniques like Field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD) and Fourier transform Infrared spectroscopy (FTIR) etc,. Electrochemical Quartz crystal microbalance (EQCM) studies helped out to calculate the total mass change during Co-MnHCF formation. Electrochemical studies reveal that the formal redox potentials of both Co and MnHCF films remained close to that of newly formed Co-MnHCF hybrid films. These 3D modified films were successfully applied for two different electrochemical applications i) For pseudocapacitor studies in KNO3 medium ii) Investigated the electrocatalytic behaviour of redox film towards water oxidation reaction in alkaline medium. Electrochemical performances of newly formed Co-MnHCF are compared with their individual transition metal (Co, Mn) hexacyanoferrates. The resulting material shows a specific capacitance of 350 F g-1 through its fast reversible redox reaction of electrochemically formed Co-MnHCF modified film. Interestingly we showed the overpotential of 450 mV (from its thermodynamic voltage 1.2 V) to attain its optimum current density of 10 mA cm-2 for O2 evolution in alkaline medium.

  9. Sulfur in the Early Martian Atmosphere Revisited: Experiments with a 3-D Global Climate Model

    NASA Astrophysics Data System (ADS)

    Kerber, L.; Forget, F.; Wordsworth, R.

    2013-09-01

    [8]. A successful working model for the early Martian atmosphere and hydrosphere must be able not only to produce conditions suitable for liquid water at the surface, but also to explain how the nature of this aqueous activity changed over time and eventually diminished. There are two major end-member hypotheses: first, that early Mars was wet and warm, with a sustained greenhouse that made it possible for liquid water to be stable on the surface for extended periods [e.g., 2, 12-14], and second, that early Mars was generally cold, and that most of the aqueous alteration took place underground [3,5] or during transient warm periods tied to impact cratering [15], or volcanism [16]. In both of these scenarios it is generally agreed that in order to make valley networks and sulfate deposits, a hydrological cycle is needed which is able to recycle water from the lowlands back to the highlands (i.e., the one-time emptying of a regional aquifer would not be sufficient to create the observed features) [4,17]. This would require some precipitation to fall on the southern highlands, either flowing overland or filtering into groundwater aquifers. In both cases, volcanic gases (especially SO2) have been suggested as a possible way of creating either a sustained or transient greenhouse. Several researchers have tested the addition of SO2 to climate models in order to assess whether it would provide an adequate amount of greenhouse warming to allow liquid water to flow across the surface [18-21], with differing results. Postawko and Kuhn [18] found a warming effect of 14 K in a 0.1 bar atmosphere with an SO2 abundance of 1000 ppm. Johnson et al. [20] used a 3-D global circulation model and found a warming of 15-25 K for 245 ppm of SO2 in a dry 0.5 bar atmosphere. Tian et al. [21] used a 1-D model to explore a wide range of SO2 mixing values and CO2 partial pressures, finding a warming of around ~25 K for 100 ppm in a 0.5 bar atmosphere with a fully saturated troposphere (~40 K

  10. Development and testing of stable, invariant, isoparametric curvilinear 2- and 3-D hybrid-stress elements

    NASA Technical Reports Server (NTRS)

    Punch, E. F.; Atluri, S. N.

    1984-01-01

    Linear and quadratic Serendipity hybrid-stress elements are examined in respect of stability, coordinate invariance, and optimality. A formulation based upon symmetry group theory successfully addresses these issues in undistorted geometries and is fully detailed for plane elements. The resulting least-order stable invariant stress polynomials can be applied as astute approximations in distorted cases through a variety of tensor components and variational principles. A distortion sensitivity study for two- and three-dimensional elements provides favorable numerical comparisons with the assumed displacement method.

  11. A new estimate of the global 3D geostrophic ocean circulation based on satellite data and in-situ measurements

    NASA Astrophysics Data System (ADS)

    Mulet, S.; Rio, M.-H.; Mignot, A.; Guinehut, S.; Morrow, R.

    2012-11-01

    A new estimate of the Global Ocean 3D geostrophic circulation from the surface down to 1500 m depth (Surcouf3D) has been computed for the 1993-2008 period using an observation-based approach that combines altimetry with temperature and salinity through the thermal wind equation. The validity of this simple approach was tested using a consistent dataset from a model reanalysis. Away from the boundary layers, errors are less than 10% in most places, which indicate that the thermal wind equation is a robust approximation to reconstruct the 3D oceanic circulation in the ocean interior. The Surcouf3D current field was validated in the Atlantic Ocean against in-situ observations. We considered the ANDRO current velocities deduced at 1000 m depth from Argo float displacements as well as velocity measurements at 26.5°N from the RAPID-MOCHA current meter array. The Surcouf3D currents show similar skill to the 3D velocities from the GLORYS Mercator Ocean reanalysis in reproducing the amplitude and variability of the ANDRO currents. In the upper 1000 m, high correlations are also found with in-situ velocities measured by the RAPID-MOCHA current meters. The Surcouf3D current field was then used to compute estimates of the Atlantic Meridional Overturning Circulation (AMOC) through the 25°N section, showing good comparisons with hydrographic sections from 1998 and 2004. Monthly averaged AMOC time series are also consistent with the RAPID-MOCHA array and with the GLORYS Mercator Ocean reanalysis over the April 2004-September 2007 period. Finally a 15 years long time series of monthly estimates of the AMOC was computed. The AMOC strength has a mean value of 16 Sv with an annual (resp. monthly) standard deviation of 2.4 Sv (resp. 7.1 Sv) over the 1993-2008 period. The time series, characterized by a strong variability, shows no significant trend.

  12. Finite Gyroradius Effects in the Plasma Environment Near Titan: 3D Hybrid Modeling of the T5 Encounter

    NASA Astrophysics Data System (ADS)

    Simpson, D. G.; Lipatov, A. S.; Sittler, E. C.; Cooper, J. F.; Hartle, R. E.; Sarantos, M.

    2012-12-01

    In this report we discuss the results of a 3D hybrid modeling of the interaction between Saturn's magnetosphere and Titan's atmosphere/ionosphere for the T5 encounter. The T5 flyby is the only encounter when the two main ionizing sources of Titan's atmosphere, solar radiation and corotating plasma, align quasi-anti-parallel. The model is based on recent analysis of the Cassini Plasma Spectrometer (CAPS) and the Cassini Ion and Neutral Mass Spectrometer (INMS) measurements during the T5 flyby through Titan's ram-side and polar ionosphere [1,2]. Magnetic field data was used from the MAG instrument [3]. In our model the background ions (O+, H+), all pickup ions, and ionospheric ions are considered as a particles, whereas the electrons are described as a fluid (see e.g. [4]). Inhomogeneous photoionization (in the dayside ionosphere), electron-impact ionization, and charge exchange are included in our model. The temperature of the background electrons and pickup electrons was also incorporated into the generalized Ohm's law. We also take into account collisions between ions and neutrals. In our hybrid simulations we use Chamberlain profiles for the exosphere's components. The moon is considered as a weakly conducting body. The first results of our hybrid modeling show a strong asymmetry in the background (H+, O+) and pickup (H2+, N2+, CH4+) ion density profiles. Such strong asymmetry cannot be explained by a single-fluid multi-species 3D MHD model [5], which includes complex chemistry but does not produce finite gyroradius and kinetic effects. References [1] Sittler, et al., Energy Deposition Processes in Titan's Atmosphere and Its Induced Magnetosphere. In: Titan from Cassini-Huygens, Brown, R.H., Lebreton, J.P., Waite, J.H., Eds., Springer, (Dordrecht, Heidelberg, London, New York), pp. 393-455, 2010. [2] Agren, K., et al., On magnetosphere electron impact ionization and dynamics in Titan's ram-side and polar ionosphere -- a Cassini case study, Ann. Geophys., 25, 2359

  13. On the Global Regularity of a Helical-Decimated Version of the 3D Navier-Stokes Equations

    NASA Astrophysics Data System (ADS)

    Biferale, Luca; Titi, Edriss S.

    2013-06-01

    We study the global regularity, for all time and all initial data in H 1/2, of a recently introduced decimated version of the incompressible 3D Navier-Stokes (dNS) equations. The model is based on a projection of the dynamical evolution of Navier-Stokes (NS) equations into the subspace where helicity (the L 2-scalar product of velocity and vorticity) is sign-definite. The presence of a second (beside energy) sign-definite inviscid conserved quadratic quantity, which is equivalent to the H 1/2-Sobolev norm, allows us to demonstrate global existence and uniqueness, of space-periodic solutions, together with continuity with respect to the initial conditions, for this decimated 3D model. This is achieved thanks to the establishment of two new estimates, for this 3D model, which show that the H 1/2 and the time average of the square of the H 3/2 norms of the velocity field remain finite. Such two additional bounds are known, in the spirit of the work of H. Fujita and T. Kato (Arch. Ration. Mech. Anal. 16:269-315, 1964; Rend. Semin. Mat. Univ. Padova 32:243-260, 1962), to be sufficient for showing well-posedness for the 3D NS equations. Furthermore, they are directly linked to the helicity evolution for the dNS model, and therefore with a clear physical meaning and consequences.

  14. Jovian Plasma Torus Interaction with Europa: 3D Hybrid Kinetic Simulation. First results

    NASA Technical Reports Server (NTRS)

    Lipatov, A. S.; Cooper, J. F.; Paterson, W. R.; Sittler, E. C.; Hartle, R. E.; Simpson, D. G.

    2010-01-01

    The hybrid kinetic model supports comprehensive simulation of the interaction between different spatial and energetic elements of the Europa-moon-magnetosphere system with respect to variable upstream magnetic field and flux or density distributions of plasma and energetic ions, electrons, and neutral atoms. This capability is critical for improving the interpretation of the existing Europa flyby measurements from the Galileo orbiter mission, and for planning flyby and orbital measurements, (including the surface and atmospheric compositions) for future missions. The simulations are based on recent models of the atmosphere of Europa (Cassidy etal.,2007;Shematovichetal.,2005). In contrast to previous approaches with MHD simulations, the hybrid model allows us to fully take into account the finite gyro radius effect and electron pressure, and to correctly estimate the ion velocity distribution and the fluxes along the magnetic field (assuming an initial Maxwellian velocity distribution for upstream background ions).Non-thermal distributions of upstream plasma will be addressed in future work. Photoionization,electron-impact ionization, charge exchange and collisions between the ions and neutrals are also included in our model. We consider two models for background plasma:(a) with O(++) ions; (b) with O(++) and S(++) ions. The majority of O2 atmosphere is thermal with an extended cold population (Cassidyetal.,2007). A few first simulations already include an induced magnetic dipole; however, several important effects of induced magnetic fields arising from oceanic shell conductivity will be addressed in later work.

  15. Patient-specific reconstruction utilizing computer assisted 3D modelling for partial bone flap defect in hybrid cranioplasty

    NASA Astrophysics Data System (ADS)

    Hueh, Low Peh; Abdullah, Johari Yap; Abdullah, Abdul Manaf; Yahya, Suzana; Idris, Zamzuri; Mohamad, Dasmawati

    2016-12-01

    Autologous cranioplasty using a patient's original bone flap remain the commonest practice nowadays. However, partial bone flap defect is commonly encountered. Replacing the bone flap with pre-moulded synthetic bone flap is costly and not affordable to many patients. Hence most of the small to medium size defect was topped up with alloplastic material on a free hand basis intra-operatively which often resulted in inaccurate implant approximation with unsatisfactory cosmetic result. This study aims to evaluate implant accuracy and cosmetic outcome of cranioplasty candidates who underwent partial bone flap reconstruction utilising computer assisted 3D modelling. 3D images of the skull were obtained from post-craniectomy axial 1-mm spiral computed tomography (CT) scans and a virtual 3D model was generated using the Materialise Mimics software. The Materialise 3-Matic was then utilised to design a patient-specific implant. Prefabrication of the implant was performed by the 3D Objet printer, and a negative gypsum mold was created with the prefabricated cranial implant. Intraoperatively, a hybrid polymethyl methacrylate (PMMA)-autologous cranial implant was produced using the gypsum mold, and fit into the cranial defect. This study is still ongoing at the moment. To date, two men has underwent partial bone flap reconstruction utilising this technique and both revealed satisfactory implant alignment with favourable cosmesis. Mean implant size was 12cm2, and the mean duration of intraoperative reconstruction for the partial bone flap defect was 40 minutes. No significant complication was reported. As a conclusion, this new technique and approach resulted in satisfactory implant alignment and favourable cosmetic outcome. However, more study samples are needed to increase the validity of the study results.

  16. Efficient global optimization based 3D carotid AB-LIB MRI segmentation by simultaneously evolving coupled surfaces.

    PubMed

    Ukwatta, Eranga; Yuan, Jing; Rajchl, Martin; Fenster, Aaron

    2012-01-01

    Magnetic resonance (MR) imaging of carotid atherosclerosis biomarkers are increasingly being investigated for the risk assessment of vulnerable plaques. A fast and robust 3D segmentation of the carotid adventitia (AB) and lumen-intima (LIB) boundaries can greatly alleviate the measurement burden of generating quantitative imaging biomarkers in clinical research. In this paper, we propose a novel global optimization-based approach to segment the carotid AB and LIB from 3D T1-weighted black blood MR images, by simultaneously evolving two coupled surfaces with enforcement of anatomical consistency of the AB and LIB. We show that the evolution of two surfaces at each discrete time-frame can be optimized exactly and globally by means of convex relaxation. Our continuous max-flow based algorithm is implemented in GPUs to achieve high computational performance. The experiment results from 16 carotid MR images show that the algorithm obtained high agreement with manual segmentations and achieved high repeatability in segmentation.

  17. Fabrication of 3D porous SF/β-TCP hybrid scaffolds for bone tissue reconstruction.

    PubMed

    Park, Hyun Jung; Min, Kyung Dan; Lee, Min Chae; Kim, Soo Hyeon; Lee, Ok Joo; Ju, Hyung Woo; Moon, Bo Mi; Lee, Jung Min; Park, Ye Ri; Kim, Dong Wook; Jeong, Ju Yeon; Park, Chan Hum

    2016-07-01

    Bio-ceramic is a biomaterial actively studied in the field of bone tissue engineering. But, only certain ceramic materials can resolve the corrosion problem and possess the biological affinity of conventional metal biomaterials. Therefore, the recent development of composites of hybrid composites and polymers has been widely studied. In this study, we aimed to select the best scaffold of silk fibroin and β-TCP hybrid for bone tissue engineering. We fabricated three groups of scaffold such as SF (silk fibroin scaffold), GS (silk fibroin/small granule size of β-TCP scaffold) and GM (silk fibroin/medium granule size of β-TCP scaffold), and we compared the characteristics of each group. During characterization of the scaffold, we used scanning electron microscopy (SEM) and a Fourier transform infrared spectroscopy (FTIR) for structural analysis. We compared the physiological properties of the scaffold regarding the swelling ratio, water uptake and porosity. To evaluate the mechanical properties, we examined the compressive strength of the scaffold. During in vitro testing, we evaluated cell attachment and cell proliferation (CCK-8). Finally, we confirmed in vivo new bone regeneration from the implanted scaffolds using histological staining and micro-CT. From these evaluations, the fabricated scaffold demonstrated high porosity with good inter-pore connectivity, showed good biocompatibility and high compressive strength and modulus. In particular, the present study indicates that the GM scaffold using β-TCP accelerates new bone regeneration of implanted scaffolds. Accordingly, our scaffold is expected to act a useful application in the field of bone tissue engineering. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 1779-1787, 2016.

  18. Solution-processed, hybrid 2D/3D MoS2/Si heterostructures with superior junction characteristics

    NASA Astrophysics Data System (ADS)

    Mukherjee, S.; Biswas, S.; Das, S.; Ray, S. K.

    2017-03-01

    We report a theoretical and experimental investigation of the hybrid heterostructure interfaces between atomically thin MoS2 nanocrystals (NCs) on Si platform for their potential applications towards next-generation electrical and optical devices. Mie theory-based numerical analysis and COMSOL simulations based on the finite element method have been utilized to study the optical absorption characteristics and light–matter interactions in variable-sized MoS2 NCs. The size-dependent absorption characteristics and the enhancement of electric field of the heterojunction in the UV-visible spectral range agree well with the experimental results. A lithography-free, wafer-scale, 2D material on a 3D substrate hybrid vertical heterostructure has been fabricated using colloidal n-MoS2 NCs on p-Si. The fabricated p-n heterojunction exhibited excellent junction characteristics with a high rectification ratio suitable for voltage clipper and rectifier applications. The current–voltage characteristics of the devices under illumination have been performed in the temperature range of 10–300 K. The device exhibits a high photo-to-dark current ratio of ∼3 × 103 and a responsivity comparable to a commercial Si photodetector. The excellent heterojunction characteristics demonstrate the great potential of MoS2 NC-based hybrid electronic and optoelectronic devices in the near future.

  19. Solution-processed, hybrid 2D/3D MoS2/Si heterostructures with superior junction characteristics.

    PubMed

    Mukherjee, S; Biswas, S; Das, S; Ray, S K

    2017-03-01

    We report a theoretical and experimental investigation of the hybrid heterostructure interfaces between atomically thin MoS2 nanocrystals (NCs) on Si platform for their potential applications towards next-generation electrical and optical devices. Mie theory-based numerical analysis and COMSOL simulations based on the finite element method have been utilized to study the optical absorption characteristics and light-matter interactions in variable-sized MoS2 NCs. The size-dependent absorption characteristics and the enhancement of electric field of the heterojunction in the UV-visible spectral range agree well with the experimental results. A lithography-free, wafer-scale, 2D material on a 3D substrate hybrid vertical heterostructure has been fabricated using colloidal n-MoS2 NCs on p-Si. The fabricated p-n heterojunction exhibited excellent junction characteristics with a high rectification ratio suitable for voltage clipper and rectifier applications. The current-voltage characteristics of the devices under illumination have been performed in the temperature range of 10-300 K. The device exhibits a high photo-to-dark current ratio of ∼3 × 10(3) and a responsivity comparable to a commercial Si photodetector. The excellent heterojunction characteristics demonstrate the great potential of MoS2 NC-based hybrid electronic and optoelectronic devices in the near future.

  20. 1D-3D hybrid modeling-from multi-compartment models to full resolution models in space and time.

    PubMed

    Grein, Stephan; Stepniewski, Martin; Reiter, Sebastian; Knodel, Markus M; Queisser, Gillian

    2014-01-01

    Investigation of cellular and network dynamics in the brain by means of modeling and simulation has evolved into a highly interdisciplinary field, that uses sophisticated modeling and simulation approaches to understand distinct areas of brain function. Depending on the underlying complexity, these models vary in their level of detail, in order to cope with the attached computational cost. Hence for large network simulations, single neurons are typically reduced to time-dependent signal processors, dismissing the spatial aspect of each cell. For single cell or networks with relatively small numbers of neurons, general purpose simulators allow for space and time-dependent simulations of electrical signal processing, based on the cable equation theory. An emerging field in Computational Neuroscience encompasses a new level of detail by incorporating the full three-dimensional morphology of cells and organelles into three-dimensional, space and time-dependent, simulations. While every approach has its advantages and limitations, such as computational cost, integrated and methods-spanning simulation approaches, depending on the network size could establish new ways to investigate the brain. In this paper we present a hybrid simulation approach, that makes use of reduced 1D-models using e.g., the NEURON simulator-which couples to fully resolved models for simulating cellular and sub-cellular dynamics, including the detailed three-dimensional morphology of neurons and organelles. In order to couple 1D- and 3D-simulations, we present a geometry-, membrane potential- and intracellular concentration mapping framework, with which graph- based morphologies, e.g., in the swc- or hoc-format, are mapped to full surface and volume representations of the neuron and computational data from 1D-simulations can be used as boundary conditions for full 3D simulations and vice versa. Thus, established models and data, based on general purpose 1D-simulators, can be directly coupled to the

  1. 1D-3D hybrid modeling—from multi-compartment models to full resolution models in space and time

    PubMed Central

    Grein, Stephan; Stepniewski, Martin; Reiter, Sebastian; Knodel, Markus M.; Queisser, Gillian

    2014-01-01

    Investigation of cellular and network dynamics in the brain by means of modeling and simulation has evolved into a highly interdisciplinary field, that uses sophisticated modeling and simulation approaches to understand distinct areas of brain function. Depending on the underlying complexity, these models vary in their level of detail, in order to cope with the attached computational cost. Hence for large network simulations, single neurons are typically reduced to time-dependent signal processors, dismissing the spatial aspect of each cell. For single cell or networks with relatively small numbers of neurons, general purpose simulators allow for space and time-dependent simulations of electrical signal processing, based on the cable equation theory. An emerging field in Computational Neuroscience encompasses a new level of detail by incorporating the full three-dimensional morphology of cells and organelles into three-dimensional, space and time-dependent, simulations. While every approach has its advantages and limitations, such as computational cost, integrated and methods-spanning simulation approaches, depending on the network size could establish new ways to investigate the brain. In this paper we present a hybrid simulation approach, that makes use of reduced 1D-models using e.g., the NEURON simulator—which couples to fully resolved models for simulating cellular and sub-cellular dynamics, including the detailed three-dimensional morphology of neurons and organelles. In order to couple 1D- and 3D-simulations, we present a geometry-, membrane potential- and intracellular concentration mapping framework, with which graph- based morphologies, e.g., in the swc- or hoc-format, are mapped to full surface and volume representations of the neuron and computational data from 1D-simulations can be used as boundary conditions for full 3D simulations and vice versa. Thus, established models and data, based on general purpose 1D-simulators, can be directly coupled to

  2. Thiol–ene-based biological/synthetic hybrid biomatrix for 3-D living cell culture

    PubMed Central

    Xu, Kedi; Fu, Yao; Chung, WeiJu; Zheng, Xiaoxiang; Cui, Yujia; Hsu, Ian C.; Kao, Weiyuan John

    2013-01-01

    Although various cell encapsulation materials are available commercially for a wide range of potential therapeutic cells, their combined clinical impact remains inconsistent. Synthetic materials such as poly(ethylene glycol) (PEG) hydrogels are mechanically robust and have been extensively explored but lack natural biofunctionality. Naturally derived materials including collagen, fibrin and alginate-chitosan are often labile and mechanically weak. In this paper we report the development of a hybrid biomatrix based on the thiol-ene reaction of PEG diacrylate (PEGdA) and cysteine/PEG-modified gelatin (gel-PEG-Cys). We hypothesized that covalent crosslinking decreases gelatin dissolution thus increasing gelatin resident time within the matrix and the duration of its biofunctionality; at the same time the relative ratio of PEGdA to gel-PEG-Cys in the matrix formulation directly affects hydrogel bulk and local microenvironment properties. Bulk viscoelastic properties were highly dependent on PEGdA concentration and total water content, while gel-PEG-Cys concentration was more critical to swelling profiles. Microviscoelastic properties were related to polymer concentration. The covalently crosslinked gel-PEG-Cys with PEGdA decreased gelatin dissolution out of the matrix and collagenase-mediated degradation. Fibroblasts and keratinocyte increased adhesion density and formed intercellular connections on stiffer hydrogel surfaces, while cells exhibited more cytoplasmic spreading and proliferation when entrapped within softer hydrogels. Hence, this material system contains multiparametric factors that can easily be controlled to modulate the chemical, physical and biological properties of the biomatrix for soft tissue scaffolding and cell presentation to reconstruct lost tissue architecture and physical functionality. PMID:22484717

  3. A set of parallel, implicit methods for a reconstructed discontinuous Galerkin method for compressible flows on 3D hybrid grids

    SciTech Connect

    Xia, Yidong; Luo, Hong; Frisbey, Megan; Nourgaliev, Robert

    2014-07-01

    A set of implicit methods are proposed for a third-order hierarchical WENO reconstructed discontinuous Galerkin method for compressible flows on 3D hybrid grids. An attractive feature in these methods are the application of the Jacobian matrix based on the P1 element approximation, resulting in a huge reduction of memory requirement compared with DG (P2). Also, three approaches -- analytical derivation, divided differencing, and automatic differentiation (AD) are presented to construct the Jacobian matrix respectively, where the AD approach shows the best robustness. A variety of compressible flow problems are computed to demonstrate the fast convergence property of the implemented flow solver. Furthermore, an SPMD (single program, multiple data) programming paradigm based on MPI is proposed to achieve parallelism. The numerical results on complex geometries indicate that this low-storage implicit method can provide a viable and attractive DG solution for complicated flows of practical importance.

  4. A set of parallel, implicit methods for a reconstructed discontinuous Galerkin method for compressible flows on 3D hybrid grids

    DOE PAGES

    Xia, Yidong; Luo, Hong; Frisbey, Megan; ...

    2014-07-01

    A set of implicit methods are proposed for a third-order hierarchical WENO reconstructed discontinuous Galerkin method for compressible flows on 3D hybrid grids. An attractive feature in these methods are the application of the Jacobian matrix based on the P1 element approximation, resulting in a huge reduction of memory requirement compared with DG (P2). Also, three approaches -- analytical derivation, divided differencing, and automatic differentiation (AD) are presented to construct the Jacobian matrix respectively, where the AD approach shows the best robustness. A variety of compressible flow problems are computed to demonstrate the fast convergence property of the implemented flowmore » solver. Furthermore, an SPMD (single program, multiple data) programming paradigm based on MPI is proposed to achieve parallelism. The numerical results on complex geometries indicate that this low-storage implicit method can provide a viable and attractive DG solution for complicated flows of practical importance.« less

  5. Hybrid Metrology and 3D-AFM Enhancement for CD Metrology Dedicated to 28 nm Node and Below Requirements

    SciTech Connect

    Foucher, J.; Faurie, P.; Dourthe, L.

    2011-11-10

    The measurement accuracy is becoming one of the major components that have to be controlled in order to guarantee sufficient production yield. Already at the R and D level, we have to come up with the accurate measurements of sub-40 nm dense trenches and contact holes coming from 193 immersion lithography or E-Beam lithography. Current production CD (Critical Dimension) metrology techniques such as CD-SEM (CD-Scanning Electron Microscope) and OCD (Optical Critical Dimension) are limited in relative accuracy for various reasons (i.e electron proximity effect, outputs parameters correlation, stack influence, electron interaction with materials...). Therefore, time for R and D is increasing, process windows degrade and finally production yield can decrease because you cannot manufactured correctly if you are unable to measure correctly. A new high volume manufacturing (HVM) CD metrology solution has to be found in order to improve the relative accuracy of production environment otherwise current CD Metrology solution will very soon get out of steam.In this paper, we will present a potential Hybrid CD metrology solution that smartly tuned 3D-AFM (3D-Atomic Force Microscope) and CD-SEM data in order to add accuracy both in R and D and production. The final goal for 'chip makers' is to improve yield and save R and D and production costs through real-time feedback loop implement on CD metrology routines. Such solution can be implemented and extended to any kind of CD metrology solution. In a 2{sup nd} part we will discuss and present results regarding a new AFM3D probes breakthrough with the introduction of full carbon tips made will E-Beam Deposition process. The goal is to overcome the current limitations of conventional flared silicon tips which are definitely not suitable for sub-32 nm nodes production.

  6. Hybrid Metrology & 3D-AFM Enhancement for CD Metrology Dedicated to 28 nm Node and Below Requirements

    NASA Astrophysics Data System (ADS)

    Foucher, J.; Faurie, P.; Dourthe, L.; Irmer, B.; Penzkofer, C.

    2011-11-01

    The measurement accuracy is becoming one of the major components that have to be controlled in order to guarantee sufficient production yield. Already at the R&D level, we have to come up with the accurate measurements of sub-40 nm dense trenches and contact holes coming from 193 immersion lithography or E-Beam lithography. Current production CD (Critical Dimension) metrology techniques such as CD-SEM (CD-Scanning Electron Microscope) and OCD (Optical Critical Dimension) are limited in relative accuracy for various reasons (i.e electron proximity effect, outputs parameters correlation, stack influence, electron interaction with materials…). Therefore, time for R&D is increasing, process windows degrade and finally production yield can decrease because you cannot manufactured correctly if you are unable to measure correctly. A new high volume manufacturing (HVM) CD metrology solution has to be found in order to improve the relative accuracy of production environment otherwise current CD Metrology solution will very soon get out of steam. In this paper, we will present a potential Hybrid CD metrology solution that smartly tuned 3D-AFM (3D-Atomic Force Microscope) and CD-SEM data in order to add accuracy both in R&D and production. The final goal for "chip makers" is to improve yield and save R&D and production costs through real-time feedback loop implement on CD metrology routines. Such solution can be implemented and extended to any kind of CD metrology solution. In a 2nd part we will discuss and present results regarding a new AFM3D probes breakthrough with the introduction of full carbon tips made will E-Beam Deposition process. The goal is to overcome the current limitations of conventional flared silicon tips which are definitely not suitable for sub-32 nm nodes production.

  7. CQL3D-Hybrid-FOW modeling of the temporal dynamics of NSTX NBI+HHFW discharges

    SciTech Connect

    Harvey, R. W.; Petrov, Yu. V.; Liu, D.; Heidbrink, W. W.; Taylor, G.; Bonoli, P. T.

    2014-02-12

    The CQL3D Fokker-Planck code[1] has been upgraded to include physics of finite-orbit-width (FOW) guiding-center orbits[2,3], as compared with the previous zero-orbit-width (ZOW) model, and a recent first-order orbit calculation[2]. The Fast Ion Diagnostic FIDA[4,5] signal resulting from neutral beam (NBI) and high harmonic fast wave (HHFW) RF power injected into the NSTX spherical tokamak can now be modeled quite accurately, using ion distributions from the CQL3D-Hybrid-FOW code, a rapidly executing variant that includes FOW+gyro-orbit losses to the plasma edge, FOW effects on NBI injection and HHFW diffusion, but does not include neoclassical radial diffusion. Accurate simulation of prompt fast ion (FI) losses is a key feature of the marked modeling improvement relative to previous ZOW results. By comparing NBI-only and NBI+HHFW shots, independent confirmation of the usual 35% edge loss of HHFW in NSTX is obtained. Further, HHFW prompt losses from the plasma core are shown to be 3X as large (>25%) as the NBI-only case. The modulated NBI and time-dependent background plasma variations and charge exchange losses of fast ions are accounted for, and the temporal neutron variation is in approximate agreement with NSTX observations.

  8. CQL3D-Hybrid-FOW modeling of the temporal dynamics of NSTX NBI+HHFW discharges

    NASA Astrophysics Data System (ADS)

    Harvey, R. W.; Petrov, Yu. V.; Liu, D.; Heidbrink, W. W.; Taylor, G.; Bonoli, P. T.

    2014-02-01

    The CQL3D Fokker-Planck code[1] has been upgraded to include physics of finite-orbit-width (FOW) guiding-center orbits[2,3], as compared with the previous zero-orbit-width (ZOW) model, and a recent first-order orbit calculation[2]. The Fast Ion Diagnostic FIDA[4,5] signal resulting from neutral beam (NBI) and high harmonic fast wave (HHFW) RF power injected into the NSTX spherical tokamak can now be modeled quite accurately, using ion distributions from the CQL3D-Hybrid-FOW code, a rapidly executing variant that includes FOW+gyro-orbit losses to the plasma edge, FOW effects on NBI injection and HHFW diffusion, but does not include neoclassical radial diffusion. Accurate simulation of prompt fast ion (FI) losses is a key feature of the marked modeling improvement relative to previous ZOW results. By comparing NBI-only and NBI+HHFW shots, independent confirmation of the usual 35% edge loss of HHFW in NSTX is obtained. Further, HHFW prompt losses from the plasma core are shown to be 3X as large (>25%) as the NBI-only case. The modulated NBI and time-dependent background plasma variations and charge exchange losses of fast ions are accounted for, and the temporal neutron variation is in approximate agreement with NSTX observations.

  9. A Hybrid Method for Endocardial Contour Extraction of Right Ventricle in 4-Slices from 3D Echocardiography Dataset.

    PubMed

    Dawood, Faten A; Rahmat, Rahmita W; Kadiman, Suhaini B; Abdullah, Lili N; Zamrin, Mohd D

    2014-01-01

    This paper presents a hybrid method to extract endocardial contour of the right ventricular (RV) in 4-slices from 3D echocardiography dataset. The overall framework comprises four processing phases. In Phase I, the region of interest (ROI) is identified by estimating the cavity boundary. Speckle noise reduction and contrast enhancement were implemented in Phase II as preprocessing tasks. In Phase III, the RV cavity region was segmented by generating intensity threshold which was used for once for all frames. Finally, Phase IV is proposed to extract the RV endocardial contour in a complete cardiac cycle using a combination of shape-based contour detection and improved radial search algorithm. The proposed method was applied to 16 datasets of 3D echocardiography encompassing the RV in long-axis view. The accuracy of experimental results obtained by the proposed method was evaluated qualitatively and quantitatively. It has been done by comparing the segmentation results of RV cavity based on endocardial contour extraction with the ground truth. The comparative analysis results show that the proposed method performs efficiently in all datasets with overall performance of 95% and the root mean square distances (RMSD) measure in terms of mean ± SD was found to be 2.21 ± 0.35 mm for RV endocardial contours.

  10. Hybrid microscaffold-based 3D bioprinting of multi-cellular constructs with high compressive strength: A new biofabrication strategy

    PubMed Central

    Tan, Yu Jun; Tan, Xipeng; Yeong, Wai Yee; Tor, Shu Beng

    2016-01-01

    A hybrid 3D bioprinting approach using porous microscaffolds and extrusion-based printing method is presented. Bioink constitutes of cell-laden poly(D,L-lactic-co-glycolic acid) (PLGA) porous microspheres with thin encapsulation of agarose-collagen composite hydrogel (AC hydrogel). Highly porous microspheres enable cells to adhere and proliferate before printing. Meanwhile, AC hydrogel allows a smooth delivery of cell-laden microspheres (CLMs), with immediate gelation of construct upon printing on cold build platform. Collagen fibrils were formed in the AC hydrogel during culture at body temperature, improving the cell affinity and spreading compared to pure agarose hydrogel. Cells were proven to proliferate in the bioink and the bioprinted construct. High cell viability up to 14 days was observed. The compressive strength of the bioink is more than 100 times superior to those of pure AC hydrogel. A potential alternative in tissue engineering of tissue replacements and biological models is made possible by combining the advantages of the conventional solid scaffolds with the new 3D bioprinting technology. PMID:27966623

  11. A global 3-D MHD model of the solar wind with Alfven waves

    NASA Technical Reports Server (NTRS)

    Usmanov, A. V.

    1995-01-01

    A fully three-dimensional solar wind model that incorporates momentum and heat addition from Alfven waves is developed. The proposed model upgrades the previous one by considering self-consistently the total system consisting of Alfven waves propagating outward from the Sun and the mean polytropic solar wind flow. The simulation region extends from the coronal base (1 R(sub s) out to beyond 1 AU. The fully 3-D MHD equations written in spherical coordinates are solved in the frame of reference corotating with the Sun. At the inner boundary, the photospheric magnetic field observations are taken as boundary condition and wave energy influx is prescribed to be proportional to the magnetic field strength. The results of the model application for several time intervals are presented.

  12. Validation of "AW3D" Global Dsm Generated from Alos Prism

    NASA Astrophysics Data System (ADS)

    Takaku, Junichi; Tadono, Takeo; Tsutsui, Ken; Ichikawa, Mayumi

    2016-06-01

    Panchromatic Remote-sensing Instrument for Stereo Mapping (PRISM), one of onboard sensors carried by Advanced Land Observing Satellite (ALOS), was designed to generate worldwide topographic data with its optical stereoscopic observation. It has an exclusive ability to perform a triplet stereo observation which views forward, nadir, and backward along the satellite track in 2.5 m ground resolution, and collected its derived images all over the world during the mission life of the satellite from 2006 through 2011. A new project, which generates global elevation datasets with the image archives, was started in 2014. The data is processed in unprecedented 5 m grid spacing utilizing the original triplet stereo images in 2.5 m resolution. As the number of processed data is growing steadily so that the global land areas are almost covered, a trend of global data qualities became apparent. This paper reports on up-to-date results of the validations for the accuracy of data products as well as the status of data coverage in global areas. The accuracies and error characteristics of datasets are analyzed by the comparison with existing global datasets such as Ice, Cloud, and land Elevation Satellite (ICESat) data, as well as ground control points (GCPs) and the reference Digital Elevation Model (DEM) derived from the airborne Light Detection and Ranging (LiDAR).

  13. Development of a hybrid 3-D hydrological model to simulate hillslopes and the regional unconfined aquifer system in Earth system models

    NASA Astrophysics Data System (ADS)

    Hazenberg, P.; Broxton, P. D.; Brunke, M.; Gochis, D.; Niu, G. Y.; Pelletier, J. D.; Troch, P. A. A.; Zeng, X.

    2015-12-01

    The terrestrial hydrological system, including surface and subsurface water, is an essential component of the Earth's climate system. Over the past few decades, land surface modelers have built one-dimensional (1D) models resolving the vertical flow of water through the soil column for use in Earth system models (ESMs). These models generally have a relatively coarse model grid size (~25-100 km) and only account for sub-grid lateral hydrological variations using simple parameterization schemes. At the same time, hydrologists have developed detailed high-resolution (~0.1-10 km grid size) three dimensional (3D) models and showed the importance of accounting for the vertical and lateral redistribution of surface and subsurface water on soil moisture, the surface energy balance and ecosystem dynamics on these smaller scales. However, computational constraints have limited the implementation of the high-resolution models for continental and global scale applications. The current work presents a hybrid-3D hydrological approach is presented, where the 1D vertical soil column model (available in many ESMs) is coupled with a high-resolution lateral flow model (h2D) to simulate subsurface flow and overland flow. H2D accounts for both local-scale hillslope and regional-scale unconfined aquifer responses (i.e. riparian zone and wetlands). This approach was shown to give comparable results as those obtained by an explicit 3D Richards model for the subsurface, but improves runtime efficiency considerably. The h3D approach is implemented for the Delaware river basin, where Noah-MP land surface model (LSM) is used to calculated vertical energy and water exchanges with the atmosphere using a 10km grid resolution. Noah-MP was coupled within the WRF-Hydro infrastructure with the lateral 1km grid resolution h2D model, for which the average depth-to-bedrock, hillslope width function and soil parameters were estimated from digital datasets. The ability of this h3D approach to simulate

  14. Multi-sensor super-resolution for hybrid range imaging with application to 3-D endoscopy and open surgery.

    PubMed

    Köhler, Thomas; Haase, Sven; Bauer, Sebastian; Wasza, Jakob; Kilgus, Thomas; Maier-Hein, Lena; Stock, Christian; Hornegger, Joachim; Feußner, Hubertus

    2015-08-01

    In this paper, we propose a multi-sensor super-resolution framework for hybrid imaging to super-resolve data from one modality by taking advantage of additional guidance images of a complementary modality. This concept is applied to hybrid 3-D range imaging in image-guided surgery, where high-quality photometric data is exploited to enhance range images of low spatial resolution. We formulate super-resolution based on the maximum a-posteriori (MAP) principle and reconstruct high-resolution range data from multiple low-resolution frames and complementary photometric information. Robust motion estimation as required for super-resolution is performed on photometric data to derive displacement fields of subpixel accuracy for the associated range images. For improved reconstruction of depth discontinuities, a novel adaptive regularizer exploiting correlations between both modalities is embedded to MAP estimation. We evaluated our method on synthetic data as well as ex-vivo images in open surgery and endoscopy. The proposed multi-sensor framework improves the peak signal-to-noise ratio by 2 dB and structural similarity by 0.03 on average compared to conventional single-sensor approaches. In ex-vivo experiments on porcine organs, our method achieves substantial improvements in terms of depth discontinuity reconstruction.

  15. A global model simulation for 3-D radiative transfer impact on surface hydrology over the Sierra Nevada and Rocky Mountains

    DOE PAGES

    Lee, W.-L.; Gu, Y.; Liou, K. N.; ...

    2015-05-19

    We investigate 3-D mountain effects on solar flux distributions and their impact on surface hydrology over the western United States, specifically the Rocky Mountains and the Sierra Nevada, using the global CCSM4 (Community Climate System Model version 4; Community Atmosphere Model/Community Land Model – CAM4/CLM4) with a 0.23° × 0.31° resolution for simulations over 6 years. In a 3-D radiative transfer parameterization, we have updated surface topography data from a resolution of 1 km to 90 m to improve parameterization accuracy. In addition, we have also modified the upward-flux deviation (3-D–PP (plane-parallel)) adjustment to ensure that the energy balance atmore » the surface is conserved in global climate simulations based on 3-D radiation parameterization. We show that deviations in the net surface fluxes are not only affected by 3-D mountains but also influenced by feedbacks of cloud and snow in association with the long-term simulations. Deviations in sensible heat and surface temperature generally follow the patterns of net surface solar flux. The monthly snow water equivalent (SWE) deviations show an increase in lower elevations due to reduced snowmelt, leading to a reduction in cumulative runoff. Over higher-elevation areas, negative SWE deviations are found because of increased solar radiation available at the surface. Simulated precipitation increases for lower elevations, while it decreases for higher elevations, with a minimum in April. Liquid runoff significantly decreases at higher elevations after April due to reduced SWE and precipitation.« less

  16. A global model simulation for 3-D radiative transfer impact on surface hydrology over the Sierra Nevada and Rocky Mountains

    SciTech Connect

    Lee, W. -L.; Gu, Y.; Liou, K. N.; Leung, L. R.; Hsu, H. -H.

    2015-05-19

    We investigate 3-D mountain effects on solar flux distributions and their impact on surface hydrology over the western United States, specifically the Rocky Mountains and the Sierra Nevada, using the global CCSM4 (Community Climate System Model version 4; Community Atmosphere Model/Community Land Model – CAM4/CLM4) with a 0.23° × 0.31° resolution for simulations over 6 years. In a 3-D radiative transfer parameterization, we have updated surface topography data from a resolution of 1 km to 90 m to improve parameterization accuracy. In addition, we have also modified the upward-flux deviation (3-D–PP (plane-parallel)) adjustment to ensure that the energy balance at the surface is conserved in global climate simulations based on 3-D radiation parameterization. We show that deviations in the net surface fluxes are not only affected by 3-D mountains but also influenced by feedbacks of cloud and snow in association with the long-term simulations. Deviations in sensible heat and surface temperature generally follow the patterns of net surface solar flux. The monthly snow water equivalent (SWE) deviations show an increase in lower elevations due to reduced snowmelt, leading to a reduction in cumulative runoff. Over higher-elevation areas, negative SWE deviations are found because of increased solar radiation available at the surface. Simulated precipitation increases for lower elevations, while it decreases for higher elevations, with a minimum in April. Liquid runoff significantly decreases at higher elevations after April due to reduced SWE and precipitation.

  17. A roadmap to global illumination in 3D scenes: solutions for GPU object recognition applications

    NASA Astrophysics Data System (ADS)

    Picos, Kenia; Díaz-Ramírez, Victor H.; Tapia, Juan J.

    2014-09-01

    Light interactions with matter is of remarkable complexity. An adequate modeling of global illumination is a vastly studied topic since the beginning of computer graphics, and still is an unsolved problem. The rendering equation for global illumination is based of refraction and reflection of light in interaction with matter within an environment. This physical process possesses a high computational complexity when implemented in a digital computer. The appearance of an object depends on light interactions with the surface of the material, such as emission, scattering, and absorption. Several image-synthesis methods have been used to realistically render the appearance of light incidence on an object. Recent global illumination algorithms employ mathematical models and computational strategies that improve the efficiency of the simulation solution. This work presents a review the state of the art of global illumination algorithms and focuses on the efficiency of the solution in a computational implementation in a graphics processing unit. A reliable system is developed to simulate realistics scenes in the context of real-time object recognition under different lighting conditions. Computer simulations results are presented and discussed in terms of discrimination capability, and robustness to additive noise, when considering several lighting model reflections and multiple light sources.

  18. Titan's plasma environment: 3D hybrid kinetic modeling of the TA flyby and comparison with CAPS-ELS and RPWS LP observations

    NASA Astrophysics Data System (ADS)

    Lipatov, A. S.; Sittler, E. C.; Hartle, R. E.; Cooper, J. F.; Simpson, D. G.

    2014-04-01

    In this report we discuss the global plasma environment of the TA flyby from the perspective of 3D hybrid modeling. In our model the background, pickup, and ionospheric ions are considered as particles, whereas the electrons are described as a fluid. Inhomogeneous photoionization, electron-impact ionization and charge exchange are included in our model. We also take into account the collisions between the ions and neutrals. Our modeling shows that mass loading of the background plasma (H+, O+) by pickup ions H2+, CH4+ and N2+ differs from the T9 encounter simulations when O+ ions are not introduced into the background plasma. In our hybrid modeling we use Chamberlain profiles for the atmospheric components. We also include a simple ionosphere model with average mass M=28 amu ions that were generated inside the ionosphere. Titan's interior is considered as a weakly conducting body. Special attention has been paid to comparing the simulated pickup ion density distribution with CAPS-ELS and with RPWS LP observations by the Cassini-Huygens spacecraft along the TA trajectory. Our modeling shows an asymmetry of the ion density distribution and the magnetic field, including the formation of Alfvén wing-like structures.

  19. Connecting Global Measures of 3D Magnetic Reconnection to Local Kinetic Physics

    SciTech Connect

    Daughton, William Scott

    2015-07-16

    After giving the motivation for the work, slides present the topic under the following headings: Description of LAPD experiment; Actual simulation setup; Simple kinetic theory of ined-tied tearing; Diagnostics to characterizing 3D reconnection; Example #1 - short-tied system; and Example #2 - long line-tied system. Colorful simulations are shown for quasipotential vs field line exponentiation, field line integrated Ohms Law, and correlation with agyrotopy & energy conversion for example #1; and evolution of current density for largest case, field exponentiation vs quasi-potential, and time evolution of magnetic field lines for example #2. To satisfy line-tied boundary conditions, there is need for superposition of oblique modes--the simple two-mode approximation works surprisingly well. For force-free layers with bg >1, the fastest growing periodic modes are oblique with kxλ ~0.5. This implies a minimum length of Ly > 2πλbg. There are strong correlations between σ → Ξ → A0e (observable with spacecraft). Electron pressure tensor is the dominant non-ideal term.

  20. Accretion to magnetized stars through the Rayleigh-Taylor instability: global 3D simulations

    NASA Astrophysics Data System (ADS)

    Kulkarni, A. K.; Romanova, M. M.

    2008-05-01

    We present results of 3D simulations of magnetohydrodynamics (MHD) instabilities at the accretion disc-magnetosphere boundary. The instability is Rayleigh-Taylor, and develops for a fairly broad range of accretion rates and stellar rotation rates and magnetic fields. It manifests itself in the form of tall, thin tongues of plasma that penetrate the magnetosphere in the equatorial plane. The shape and number of the tongues changes with time on the inner disc dynamical time-scale. In contrast with funnel flows, which deposit matter mainly in the polar region, the tongues deposit matter much closer to the stellar equator. The instability appears for relatively small misalignment angles, Θ <~ 30°, between the star's rotation and magnetic axes, and is associated with higher accretion rates. The hotspots and light curves during accretion through instability are generally much more chaotic than during stable accretion. The unstable state of accretion has possible implications for quasi-periodic oscillations and intermittent pulsations from accreting systems, as well as planet migration.

  1. Online 3D Ear Recognition by Combining Global and Local Features

    PubMed Central

    Liu, Yahui; Zhang, Bob; Lu, Guangming; Zhang, David

    2016-01-01

    The three-dimensional shape of the ear has been proven to be a stable candidate for biometric authentication because of its desirable properties such as universality, uniqueness, and permanence. In this paper, a special laser scanner designed for online three-dimensional ear acquisition was described. Based on the dataset collected by our scanner, two novel feature classes were defined from a three-dimensional ear image: the global feature class (empty centers and angles) and local feature class (points, lines, and areas). These features are extracted and combined in an optimal way for three-dimensional ear recognition. Using a large dataset consisting of 2,000 samples, the experimental results illustrate the effectiveness of fusing global and local features, obtaining an equal error rate of 2.2%. PMID:27935955

  2. Global well-posedness for the 3D incompressible inhomogeneous Navier-Stokes equations and MHD equations

    NASA Astrophysics Data System (ADS)

    Zhai, Xiaoping; Yin, Zhaoyang

    2017-02-01

    The present paper is dedicated to the global well-posedness for the 3D inhomogeneous incompressible Navier-Stokes equations, in critical Besov spaces without smallness assumption on the variation of the density. We aim at extending the work by Abidi, Gui and Zhang (2012) [2], and (2013) [3] to a lower regularity index about the initial velocity. The key to that improvement is a new a priori estimate for an elliptic equation with nonconstant coefficients in Besov spaces which have the same degree as L2 in R3. Finally, we also generalize our well-posedness result to the inhomogeneous incompressible MHD equations.

  3. Global classical solutions to the 3D isentropic compressible Navier-Stokes equations in a bounded domain

    NASA Astrophysics Data System (ADS)

    Yu, Haibo; Zhao, Junning

    2017-01-01

    In this paper, we study the global existence for classical solutions to the 3D isentropic compressible Navier-Stokes equations in a cuboid domain. Compared to the Cauchy problem studied in Hoff (1995 J. Differ. Equ. 120 215-54), Hoff (2005 J. Math. Fluid Mech. 7 315-38), Huang et al (2012 Commun. Pure Appl. Math. 65 549-85), some new thoughts are applied to obtain upper bounds for density. Precisely, through piecewise estimation and some time-depending a priori estimates, we establish time-uniform upper bounds for density under the assumption that the initial energy is small. The initial vacuum is allowed.

  4. New 3D parallel GILD electromagnetic modeling and nonlinear inversion using global magnetic integral and local differential equation

    SciTech Connect

    Xie, G.; Li, J.; Majer, E.; Zuo, D.

    1998-07-01

    This paper describes a new 3D parallel GILD electromagnetic (EM) modeling and nonlinear inversion algorithm. The algorithm consists of: (a) a new magnetic integral equation instead of the electric integral equation to solve the electromagnetic forward modeling and inverse problem; (b) a collocation finite element method for solving the magnetic integral and a Galerkin finite element method for the magnetic differential equations; (c) a nonlinear regularizing optimization method to make the inversion stable and of high resolution; and (d) a new parallel 3D modeling and inversion using a global integral and local differential domain decomposition technique (GILD). The new 3D nonlinear electromagnetic inversion has been tested with synthetic data and field data. The authors obtained very good imaging for the synthetic data and reasonable subsurface EM imaging for the field data. The parallel algorithm has high parallel efficiency over 90% and can be a parallel solver for elliptic, parabolic, and hyperbolic modeling and inversion. The parallel GILD algorithm can be extended to develop a high resolution and large scale seismic and hydrology modeling and inversion in the massively parallel computer.

  5. Comparisons of 3D data products of the global atmosphere for the past 120 years

    NASA Astrophysics Data System (ADS)

    Brönnimann, Stefan; Stickler, Alexander; Compo, Gilbert P.

    2010-05-01

    In order to better understand, assess, and eventually predict climate variability and extremes, global 3-dimensional data sets of the atmosphere over a sufficiently long time period are needed. Until recently, there were mainly two reanalyses (NCEP/NCAR and ERA-40), which covered the second half of the 20th century. These are the most widely used data sets in atmospheric and climate science, but the period covered is still too short for many purposes. In cooperation with the Atmospheric Circulation Reconstructions over the Earth initiative (R. Allan, UK Met Office, www.met-acre.org/), different data products have been developed recently that allow a 4-dimensional view of the global atmosphere further back than the mid 20th century. These data sets include the Twentieth Century Reanalysis Project (G. P. Compo, P. Sardeshmukh & J. Whitaker, CU/CIRES/CDC and NOAA/ESRL, http://www.esrl.noaa.gov/psd/data/20thC_Rean/), monthly statistical reconstructions, and a new collection of historical upper-air data (CHUAN, see www.historicalupperair.org). In this presentation we show comparisons of the different data products for several case studies as well as statistically using independent data.

  6. Free-space coherent optical communication with orbital angular, momentum multiplexing/demultiplexing using a hybrid 3D photonic integrated circuit.

    PubMed

    Guan, Binbin; Scott, Ryan P; Qin, Chuan; Fontaine, Nicolas K; Su, Tiehui; Ferrari, Carlo; Cappuzzo, Mark; Klemens, Fred; Keller, Bob; Earnshaw, Mark; Yoo, S J B

    2014-01-13

    We demonstrate free-space space-division-multiplexing (SDM) with 15 orbital angular momentum (OAM) states using a three-dimensional (3D) photonic integrated circuit (PIC). The hybrid device consists of a silica planar lightwave circuit (PLC) coupled to a 3D waveguide circuit to multiplex/demultiplex OAM states. The low excess loss hybrid device is used in individual and two simultaneous OAM states multiplexing and demultiplexing link experiments with a 20 Gb/s, 1.67 b/s/Hz quadrature phase shift keyed (QPSK) signal, which shows error-free performance for 379,960 tested bits for all OAM states.

  7. Mars-solar wind interaction: LatHyS, an improved parallel 3-D multispecies hybrid model

    NASA Astrophysics Data System (ADS)

    Modolo, Ronan; Hess, Sebastien; Mancini, Marco; Leblanc, Francois; Chaufray, Jean-Yves; Brain, David; Leclercq, Ludivine; Esteban-Hernández, Rosa; Chanteur, Gerard; Weill, Philippe; González-Galindo, Francisco; Forget, Francois; Yagi, Manabu; Mazelle, Christian

    2016-07-01

    In order to better represent Mars-solar wind interaction, we present an unprecedented model achieving spatial resolution down to 50 km, a so far unexplored resolution for global kinetic models of the Martian ionized environment. Such resolution approaches the ionospheric plasma scale height. In practice, the model is derived from a first version described in Modolo et al. (2005). An important effort of parallelization has been conducted and is presented here. A better description of the ionosphere was also implemented including ionospheric chemistry, electrical conductivities, and a drag force modeling the ion-neutral collisions in the ionosphere. This new version of the code, named LatHyS (Latmos Hybrid Simulation), is here used to characterize the impact of various spatial resolutions on simulation results. In addition, and following a global model challenge effort, we present the results of simulation run for three cases which allow addressing the effect of the suprathermal corona and of the solar EUV activity on the magnetospheric plasma boundaries and on the global escape. Simulation results showed that global patterns are relatively similar for the different spatial resolution runs, but finest grid runs provide a better representation of the ionosphere and display more details of the planetary plasma dynamic. Simulation results suggest that a significant fraction of escaping O+ ions is originated from below 1200 km altitude.

  8. Evaluation of Stratospheric Transport in New 3D Models Using the Global Modeling Initiative Grading Criteria

    NASA Technical Reports Server (NTRS)

    Strahan, Susan E.; Douglass, Anne R.; Einaudi, Franco (Technical Monitor)

    2001-01-01

    The Global Modeling Initiative (GMI) Team developed objective criteria for model evaluation in order to identify the best representation of the stratosphere. This work created a method to quantitatively and objectively discriminate between different models. In the original GMI study, 3 different meteorological data sets were used to run an offline chemistry and transport model (CTM). Observationally-based grading criteria were derived and applied to these simulations and various aspects of stratospheric transport were evaluated; grades were assigned. Here we report on the application of the GMI evaluation criteria to CTM simulations integrated with a new assimilated wind data set and a new general circulation model (GCM) wind data set. The Finite Volume Community Climate Model (FV-CCM) is a new GCM developed at Goddard which uses the NCAR CCM physics and the Lin and Rood advection scheme. The FV-Data Assimilation System (FV-DAS) is a new data assimilation system which uses the FV-CCM as its core model. One year CTM simulations of 2.5 degrees longitude by 2 degrees latitude resolution were run for each wind data set. We present the evaluation of temperature and annual transport cycles in the lower and middle stratosphere in the two new CTM simulations. We include an evaluation of high latitude transport which was not part of the original GMI criteria. Grades for the new simulations will be compared with those assigned during the original GMT evaluations and areas of improvement will be identified.

  9. MERIDIONAL CIRCULATION DYNAMICS FROM 3D MAGNETOHYDRODYNAMIC GLOBAL SIMULATIONS OF SOLAR CONVECTION

    SciTech Connect

    Passos, Dário; Charbonneau, Paul; Miesch, Mark

    2015-02-10

    The form of solar meridional circulation is a very important ingredient for mean field flux transport dynamo models. However, a shroud of mystery still surrounds this large-scale flow, given that its measurement using current helioseismic techniques is challenging. In this work, we use results from three-dimensional global simulations of solar convection to infer the dynamical behavior of the established meridional circulation. We make a direct comparison between the meridional circulation that arises in these simulations and the latest observations. Based on our results, we argue that there should be an equatorward flow at the base of the convection zone at mid-latitudes, below the current maximum depth helioseismic measures can probe (0.75 R{sub ⊙}). We also provide physical arguments to justify this behavior. The simulations indicate that the meridional circulation undergoes substantial changes in morphology as the magnetic cycle unfolds. We close by discussing the importance of these dynamical changes for current methods of observation which involve long averaging periods of helioseismic data. Also noteworthy is the fact that these topological changes indicate a rich interaction between magnetic fields and plasma flows, which challenges the ubiquitous kinematic approach used in the vast majority of mean field dynamo simulations.

  10. 3D Interdigital Au/MnO2 /Au Stacked Hybrid Electrodes for On-Chip Microsupercapacitors.

    PubMed

    Hu, Haibo; Pei, Zhibin; Fan, Hongjin; Ye, Changhui

    2016-06-01

    On-chip microsupercapacitors (MSCs) have application in powering microelectronic devices. Most of previous MSCs are made from carbon materials, which have high power but low energy density. In this work, 3D interdigital Au/MnO2 /Au stacked MSCs have been fabricated based on laser printed flexible templates. This vertical-stacked electrode configuration can effectively increase the contact area between MnO2 active layer and Au conductive layer, and thus improve the electron transport and electrolyte ion diffusion, resulting in enhanced pseudocapacitive performance of MnO2 . The stacked electrode can achieve an areal capacitance up to 11.9 mF cm(-2) . Flexible and all-solid-state MSCs are assembled based on the sandwich hybrid electrodes and PVA/LiClO4 gel electrolyte and show outstanding high-rate capacity and mechanical flexibility. The laser printing technique in this work combined with the physical sputtering and electrodeposition allows fabrication of MSC array with random sizes and patterns, making them promising power sources for small-scale flexible microelectronic energy storage systems (e.g., next-generation smart phones).

  11. First Lunar Wake Passage of ARTEMIS: Discrimination of Wake Effects and Solar Wind Fluctuations by 3D Hybrid Simulations

    NASA Technical Reports Server (NTRS)

    Wiehle, S.; Plaschke, F.; Motschmann, U.; Glassmeier, K. H.; Auster, H. U.; Angelopoulos, V.; Mueller, J.; Kriegel, H.; Georgescu, E.; Halekas, J.; Sibeck, D. G.; McFadden, J. P.

    2011-01-01

    The spacecraft P1 of the new ARTEMIS (Acceleration, Reconnection, Turbulence, and Electrodynamics of the Moon's Interaction with the Sun) mission passed the lunar wake for the first time on February 13, 2010. We present magnetic field and plasma data of this event and results of 3D hybrid simulations. As the solar wind magnetic field was highly dynamic during the passage, a simulation with stationary solar wind input cannot distinguish whether distortions were caused by these solar wind variations or by the lunar wake; therefore, a dynamic real-time simulation of the flyby has been performed. The input values of this simulation are taken from NASA OMNI data and adapted to the P1 data, resulting in a good agreement between simulation and measurements. Combined with the stationary simulation showing non-transient lunar wake structures, a separation of solar wind and wake effects is achieved. An anisotropy in the magnitude of the plasma bulk flow velocity caused by a non-vanishing magnetic field component parallel to the solar wind flow and perturbations created by counterstreaming ions in the lunar wake are observed in data and simulations. The simulations help to interpret the data granting us the opportunity to examine the entire lunar plasma environment and, thus, extending the possibilities of measurements alone: A comparison of a simulation cross section to theoretical predictions of MHD wave propagation shows that all three basic MHD modes are present in the lunar wake and that their expansion governs the lunar wake refilling process.

  12. Global Warming and the Arctic in 3D: A Virtual Globe for Outreach

    NASA Astrophysics Data System (ADS)

    Manley, W. F.

    2006-12-01

    Virtual Globes provide a new way to capture and inform the public's interest in environmental change. As an example, a recent Google Earth presentation conveyed 'key findings' from the Arctic Climate Impact Assessment (ACIA, 2004) to middle school students during the 2006 INSTAAR/NSIDC Open House at the University of Colorado. The 20-minute demonstration to 180 eighth graders began with an introduction and a view of the Arctic from space, zooming into the North American Arctic, then to a placemark for the first key finding, 'Arctic climate is now warming rapidly and much larger changes are projected'. An embedded link then opened a custom web page, with brief explanatory text, along with an ACIA graphic illustrating the rise in Arctic temperature, global CO2 concentrations, and carbon emissions for the last millennium. The demo continued with an interactive tour of other key findings (Reduced Sea Ice, Changes for Animals, Melting Glaciers, Coastal Erosion, Changes in Vegetation, Melting Permafrost, and others). Each placemark was located somewhat arbitrarily (which may be a concern for some audiences), but the points represented the messages in a geographic sense and enabled a smooth visual tour of the northern latitudes. Each placemark was linked to custom web pages with photos and concise take-home messages. The demo ended with navigation to Colorado, then Boulder, then the middle school that the students attended, all the while speaking to implications as they live their lives locally. The demo piqued the students' curiosity, and in this way better conveyed important messages about the Arctic and climate change. The use of geospatial visualizations for outreach and education appears to be in its infancy, with much potential.

  13. Global brain atrophy and corticospinal tract alterations in ALS, as investigated by voxel-based morphometry of 3-D MRI.

    PubMed

    Kassubek, Jan; Unrath, Alexander; Huppertz, Hans-Jürgen; Lulé, Dorothée; Ethofer, Thomas; Sperfeld, Anne-Dorte; Ludolph, Albert C

    2005-12-01

    In ALS, advanced magnetic resonance imaging (MRI) techniques are increasingly used to investigate the underlying pathology. In this study, the technique of voxel-based morphometry (VBM) was applied to 3-D MRI data in ALS patients to localize regional grey and white matter changes. Twenty-two ALS patients (mean age 58+/-9 years) with clinically definite ALS by revised El Escorial criteria were studied. None of the patients had any signs of associated frontotemporal dementia. High-resolution 3-D MRI data sets of the whole brain, collected on a 1.5 T scanner, were analysed by statistical parametric mapping (SPM) and VBM in comparison to an age-matched normal data base consisting of 22 healthy volunteers (mean age 59+/-11 years), for grey matter and white matter segments separately. Global brain atrophy was assessed by calculation of brain parenchymal fractions (BPF). In ALS patients, BPF were significantly reduced compared to controls (p = 0.0003), indicating global brain atrophy. Regional decreases of grey matter density were found in the ALS patients at corrected p<0.01 in the right-hemispheric primary motor cortex (area of the highest Z-score) and in the left medial frontal gyrus. Furthermore, regional white matter alterations were observed along the corticospinal tracts bilaterally and in multiple smaller areas including corpus callosum, cerebellum, frontal and occipital subcortical regions. Besides considerable global atrophy in ALS, the topography of ALS-associated cerebral morphological changes could be mapped using VBM, in particular white matter signal changes along the bilateral corticospinal tracts, but also in extra-motor areas. VBM might be a potential tool to visualize disease progression in future longitudinal studies.

  14. 3D Global Climate Modelling of the environmental effect of meteoritic impacts on Early Mars

    NASA Astrophysics Data System (ADS)

    Turbet, Martin; Forget, Francois; Gillmann, Cedric; Karatekin, Ozgur; Svetsov, Vladimir; Popova, Olga; Wallemacq, Quentin

    2016-10-01

    There are now robust evidences that liquid water flowed on ancient Mars: dry river beds and lakes, hydrated sedimentary minerals and high erosion rates. Climate models that consider only CO2/H2O as greenhouse gases have been unable yet to produce warm climates suitable for liquid water on Early Mars, given the lower solar luminosity at that time. It has been suggested that the warm conditions required to explain the formation of the 3.8 Gyrs old valley networks could have been transient and produced in response to the meteoritic impacts that occured during the contemporaneous Late Heavy Bombardment (LHB). This scenario is appealing because, in a predominately cold climate, the ice tends to accumulate preferentially in the regions where the rivers were sculpted ('Icy Highlands' scenario). This would be a very efficient mechanism of recharge of the valley network water sources between two impact-induced melting events.Using the LMD Global Climate Model (LMD-GCM) designed for flexible (from cold & dry to warm & wet) conditions, we explored the environmental effect of LHB impact events of various sizes on Early Mars. Our main result is that, whatever the initial impact-induced temperatures and water vapor content injected, warm climates cannot be stable and are in fact short-lived (lifetime of ~ 5 martian years/bar of H2O injected). Moreover, we will give preliminar estimates of the amount of rainfall/snowmelt that can be produced after impact events depending on their size, following three different approaches:1) For large impact events (Dimpactor < 50km, N ~ 40) we initialize the LMD-GCM with warm/moist conditions prescribed with simple scaling laws and assuming energy conservation.2) For moderate-size events (5km < Dimpactor < 50km, N ~ 3x103) we use the SOVA hydrocode for short-term modelling of impact cratering. It provides us with post-impact temperature fields, injection of volatiles, ejecta and dust distribution that serve as input for the LMD-GCM.3

  15. A comparison study of atlas-based 3D cardiac MRI segmentation: global versus global and local transformations

    NASA Astrophysics Data System (ADS)

    Daryanani, Aditya; Dangi, Shusil; Ben-Zikri, Yehuda Kfir; Linte, Cristian A.

    2016-03-01

    Magnetic Resonance Imaging (MRI) is a standard-of-care imaging modality for cardiac function assessment and guidance of cardiac interventions thanks to its high image quality and lack of exposure to ionizing radiation. Cardiac health parameters such as left ventricular volume, ejection fraction, myocardial mass, thickness, and strain can be assessed by segmenting the heart from cardiac MRI images. Furthermore, the segmented pre-operative anatomical heart models can be used to precisely identify regions of interest to be treated during minimally invasive therapy. Hence, the use of accurate and computationally efficient segmentation techniques is critical, especially for intra-procedural guidance applications that rely on the peri-operative segmentation of subject-specific datasets without delaying the procedure workflow. Atlas-based segmentation incorporates prior knowledge of the anatomy of interest from expertly annotated image datasets. Typically, the ground truth atlas label is propagated to a test image using a combination of global and local registration. The high computational cost of non-rigid registration motivated us to obtain an initial segmentation using global transformations based on an atlas of the left ventricle from a population of patient MRI images and refine it using well developed technique based on graph cuts. Here we quantitatively compare the segmentations obtained from the global and global plus local atlases and refined using graph cut-based techniques with the expert segmentations according to several similarity metrics, including Dice correlation coefficient, Jaccard coefficient, Hausdorff distance, and Mean absolute distance error.

  16. Saturn's magnetosphere interaction with Titan for T9 encounter: 3D hybrid modeling and comparison with CAPS observations

    NASA Astrophysics Data System (ADS)

    Lipatov, A. S.; Sittler, E. C.; Hartle, R. E.; Cooper, J. F.; Simpson, D. G.

    2012-02-01

    Global dynamics of ionized and neutral gases in the environment of Titan plays an important role in the interaction of Saturn's magnetosphere with Titan. Several hybrid simulations of this problem have already been done (Brecht et al., 2000; Kallio et al., 2004; Modolo et al., 2007a; Simon et al., 2007a, 2007b; Modolo and Chanteur, 2008). Observational data from CAPS for the T9 encounter (Sittler et al., 2009) indicates an absence of O+ heavy ions in the upstream that change the models of interaction which were discussed in current publications (Kallio et al., 2004; Modolo et al., 2007a; Simon et al., 2007a, 2007b; Ma et al., 2007; Szego et al., 2007). Further analysis of the CAPS data shows very low density or even an absence of H+ ions in upstream. In this paper we discuss two models of the interaction of Saturn's magnetosphere with Titan: (A) high density of H+ ions in the upstream flow (0.1 cm-3), and (B) low density of H+ ions in the upstream flow (0.02 cm-3). The hybrid model employs a fluid description for electrons and neutrals, whereas a particle approach is used for ions. We also take into account charge-exchange and photoionization processes and solve self-consistently for electric and magnetic fields. The model atmosphere includes exospheric H+, H2+, N2+ and CH4+ pickup ion production as well as an immobile background ionosphere and a shell distribution for active ionospheric ions (Mi=28 amu). The hybrid model allows us to account for the realistic anisotropic ion velocity distribution that cannot be done in fluid simulations with isotropic temperatures. Our simulation shows an asymmetry of the ion density distribution and the magnetic field, including the formation of Alfvén wing-like structures. The results of the ion dynamics in Titan's environment are compared with Cassini T9 encounter data (CAPS).

  17. Saturn's Magnetosphere Interaction with Titan for T9 Encounter: 3D Hybrid Modeling and Comparison with CAPS Observations

    NASA Technical Reports Server (NTRS)

    Lipatov, A. S.; Sittler, E. C., Jr.; Hartle, R. E.; Cooper, J. F.; Simpson, D. G.

    2011-01-01

    Global dynamics of ionized and neutral gases in the environment of Titan plays an important role in the interaction of Saturn s magnetosphere with Titan. Several hybrid simulations of this problem have already been done (Brecht et al., 2000; Kallio et al., 2004; Modolo et al., 2007a; Simon et al., 2007a, 2007b; Modolo and Chanteur, 2008). Observational data from CAPS for the T9 encounter (Sittler et al., 2009) indicates an absence of O(+) heavy ions in the upstream that change the models of interaction which were discussed in current publications (Kallio et al., 2004; Modolo et al., 2007a; Simon et al., 2007a, 2007b; Ma et al., 2007; Szego et al., 2007). Further analysis of the CAPS data shows very low density or even an absence of H(+) ions in upstream. In this paper we discuss two models of the interaction of Saturn s magnetosphere with Titan: (A) high density of H(+) ions in the upstream flow (0.1/cu cm), and (B) low density of H(+) ions in the upstream flow (0.02/cu cm). The hybrid model employs a fluid description for electrons and neutrals, whereas a particle approach is used for ions. We also take into account charge-exchange and photoionization processes and solve self-consistently for electric and magnetic fields. The model atmosphere includes exospheric H(+), H(2+), N(2+)and CH(4+) pickup ion production as well as an immobile background ionosphere and a shell distribution for active ionospheric ions (M(sub i)=28 amu). The hybrid model allows us to account for the realistic anisotropic ion velocity distribution that cannot be done in fluid simulations with isotropic temperatures. Our simulation shows an asymmetry of the ion density distribution and the magnetic field, including the formation of Alfven wing-like structures. The results of the ion dynamics in Titan s environment are compared with Cassini T9 encounter data (CAPS).

  18. A hybrid 3D-Var data assimilation scheme for joint state and parameter estimation: application to morphodynamic modelling

    NASA Astrophysics Data System (ADS)

    Smith, P.; Nichols, N. K.; Dance, S.

    2011-12-01

    Data assimilation is typically used to provide initial conditions for state estimation; combining model predictions with observational data to produce an updated model state that most accurately characterises the true system state whilst keeping the model parameters fixed. This updated model state is then used to initiate the next model forecast. However, even with perfect initial data, inaccurate representation of model parameters will lead to the growth of model error and therefore affect the ability of our model to accurately predict the true system state. A key question in model development is how to estimate parameters a priori. In most cases, parameter estimation is addressed as a separate issue to state estimation and model calibration is performed offline in a separate calculation. Here we demonstrate how, by employing the technique of state augmentation, it is possible to use data assimilation to estimate uncertain model parameters concurrently with the model state as part of the assimilation process. We present a novel hybrid data assimilation algorithm developed for application to parameter estimation in morphodynamic models. The new approach is based on a computationally inexpensive 3D-Var scheme, where the specification of the covariance matrices is crucial for success. For combined state-parameter estimation, it is particularly important that the cross-covariances between the parameters and the state are given a good a priori specification. Early experiments indicated that in order to yield reliable estimates of the true parameters, a flow dependent representation of the state-parameter cross covariances is required. By combining ideas from 3D-Var and the extended Kalman filter we have developed a novel hybrid assimilation scheme that captures the flow dependent nature of the state-parameter cross covariances without the computational expense of explicitly propagating the full system covariance matrix. We will give details of the formulation of this

  19. A 3D hybrid praseodymium-antimony-oxochloride compound: single-crystal-to-single-crystal transformation and photocatalytic properties.

    PubMed

    Zou, Guo-Dong; Zhang, Gui-Gang; Hu, Bing; Li, Jian-Rong; Feng, Mei-Ling; Wang, Xin-Chen; Huang, Xiao-Ying

    2013-11-04

    A 3D organic-inorganic hybrid compound, (2-MepyH)3[{Fe(1,10-phen)3}3][{Pr4Sb12O18(OH)Cl(11.5)}(TDC)(4.5)({Pr4Sb12O18(OH)Cl(9.5)} Cl)]·3(2-Mepy)·28H2O (1; 2-Mepy=2-methylpyridine, 1,10-phen=1,10-phenanthroline, H2TDC=thiophene-2,5-dicarboxylic acid), was hydrothermally synthesized and structurally characterized. Unusually, two kinds of high-nuclearity clusters, namely [(Pr4Sb12O18(OH)Cl11)(COO)5](5-) and [(Pr4Sb12O18(OH)Cl9)Cl(COO)5](4-), coexist in the structure of compound 1; two of the latter clusters are doubly bridged by two μ2-Cl(-) moieties to form a new centrosymmetric dimeric cluster. An unprecedented spontaneous and reversible single-crystal-to-single-crystal transformation was observed, which simultaneously involved a notable organic-ligand movement between the metal ions and an alteration of the bridging ion in the dimeric cluster, induced by guest-release/re-adsorption, thereby giving rise to the interconversion between compound 1 and the compound (2-MepyH)3[{Fe(1,10-phen)3}3][{Pr4Sb12O18(OH)Cl(11.5)}(TDC)4({Pr4Sb12O18Cl(10.5)(TDC)(0.5)(H2O)(1.5)}O(0.5))]·25H2O (1'). The mechanism of this transformation has also been discussed in great detail. Photocatalytic H2-evolution activity was observed for compound 1' under UV light with Pt as a co-catalyst and MeOH as a sacrificial electron donor.

  20. Design and development of ultra-wideband 3 dB hybrid coupler for Ion cyclotron resonance frequency heating in tokamak

    NASA Astrophysics Data System (ADS)

    Yadav, Rana Pratap; Kumar, Sunil; Kulkarni, S. V.

    2014-04-01

    Design and development of a high power ultra-wideband, 3 dB tandem hybrid coupler is presented and its application in ICRF heating of the tokamak is discussed. In order to achieve the desired frequency band of 38-112 MHz and 200 kW power handling capability, the 3 dB hybrid coupler is developed using two 3-element 8.34 ± 0.2 dB coupled lines sections in tandem. In multi-element coupled lines, junctions are employed for the joining of coupled elements that produce the undesirable reactance called junction discontinuity effect. The effect becomes prominent in the high power multi-element coupled lines for high frequency (HF) and very high frequency(VHF) applications because of larger structural dimensions. Junction discontinuity effect significantly deteriorates coupling and output performance from the theoretical predictions. For the analysis of junction discontinuity effect and its compensation, a theoretical approach has been developed and generalized for n-element coupled lines section. The theory has been applied in the development of the 3 dB hybrid coupler. The fabricated hybrid coupler has been experimentally characterized using vector network analyzer and obtained results are found in good agreement with developed theory.

  1. New Global 3D Upper to Mid-mantle Electrical Conductivity Model Based on Observatory Data with Realistic Auroral Sources

    NASA Astrophysics Data System (ADS)

    Kelbert, A.; Egbert, G. D.; Sun, J.

    2011-12-01

    Poleward of 45-50 degrees (geomagnetic) observatory data are influenced significantly by auroral ionospheric current systems, invalidating the simplifying zonal dipole source assumption traditionally used for long period (T > 2 days) geomagnetic induction studies. Previous efforts to use these data to obtain the global electrical conductivity distribution in Earth's mantle have omitted high-latitude sites (further thinning an already sparse dataset) and/or corrected the affected transfer functions using a highly simplified model of auroral source currents. Although these strategies are partly effective, there remain clear suggestions of source contamination in most recent 3D inverse solutions - specifically, bands of conductive features are found near auroral latitudes. We report on a new approach to this problem, based on adjusting both external field structure and 3D Earth conductivity to fit observatory data. As an initial step towards full joint inversion we are using a two step procedure. In the first stage, we adopt a simplified conductivity model, with a thin-sheet of variable conductance (to represent the oceans) overlying a 1D Earth, to invert observed magnetic fields for external source spatial structure. Input data for this inversion are obtained from frequency domain principal components (PC) analysis of geomagnetic observatory hourly mean values. To make this (essentially linear) inverse problem well-posed we regularize using covariances for source field structure that are consistent with well-established properties of auroral ionospheric (and magnetospheric) current systems, and basic physics of the EM fields. In the second stage, we use a 3D finite difference inversion code, with source fields estimated from the first stage, to further fit the observatory PC modes. We incorporate higher latitude data into the inversion, and maximize the amount of available information by directly inverting the magnetic field components of the PC modes, instead of

  2. Hybrid MV-kV 3D respiratory motion tracking during radiation therapy with low imaging dose.

    PubMed

    Yan, Huagang; Li, Haiyun; Liu, Zhixiang; Nath, Ravinder; Liu, Wu

    2012-12-21

    A novel real-time adaptive MV-kV imaging framework for image-guided radiation therapy is developed to reduce the thoracic and abdominal tumor targeting uncertainty caused by respiration-induced intrafraction motion with ultra-low patient imaging dose. In our method, continuous stereoscopic MV-kV imaging is used at the beginning of a radiation therapy delivery for several seconds to measure the implanted marker positions. After this stereoscopic imaging period, the kV imager is switched off except for the times when no fiducial marker is detected in the cine-MV images. The 3D time-varying marker positions are estimated by combining the MV 2D projection data and the motion correlations between directional components of marker motion established from the stereoscopic imaging period and updated afterwards; in particular, the most likely position is assumed to be the position on the projection line that has the shortest distance to the first principal component line segment constructed from previous trajectory points. An adaptive windowed auto-regressive prediction is utilized to predict the marker position a short time later (310 ms and 460 ms in this study) to allow for tracking system latency. To demonstrate the feasibility and evaluate the accuracy of the proposed method, computer simulations were performed for both arc and fixed-gantry deliveries using 66 h of retrospective tumor motion data from 42 patients treated for thoracic or abdominal cancers. The simulations reveal that using our hybrid approach, a smaller than 1.2 mm or 1.5 mm root-mean-square tracking error can be achieved at a system latency of 310 ms or 460 ms, respectively. Because the kV imaging is only used for a short period of time in our method, extra patient imaging dose can be reduced by an order of magnitude compared to continuous MV-kV imaging, while the clinical tumor targeting accuracy for thoracic or abdominal cancers is maintained. Furthermore, no additional hardware is required

  3. Hybrid MV-kV 3D respiratory motion tracking during radiation therapy with low imaging dose

    NASA Astrophysics Data System (ADS)

    Yan, Huagang; Li, Haiyun; Liu, Zhixiang; Nath, Ravinder; Liu, Wu

    2012-12-01

    A novel real-time adaptive MV-kV imaging framework for image-guided radiation therapy is developed to reduce the thoracic and abdominal tumor targeting uncertainty caused by respiration-induced intrafraction motion with ultra-low patient imaging dose. In our method, continuous stereoscopic MV-kV imaging is used at the beginning of a radiation therapy delivery for several seconds to measure the implanted marker positions. After this stereoscopic imaging period, the kV imager is switched off except for the times when no fiducial marker is detected in the cine-MV images. The 3D time-varying marker positions are estimated by combining the MV 2D projection data and the motion correlations between directional components of marker motion established from the stereoscopic imaging period and updated afterwards; in particular, the most likely position is assumed to be the position on the projection line that has the shortest distance to the first principal component line segment constructed from previous trajectory points. An adaptive windowed auto-regressive prediction is utilized to predict the marker position a short time later (310 ms and 460 ms in this study) to allow for tracking system latency. To demonstrate the feasibility and evaluate the accuracy of the proposed method, computer simulations were performed for both arc and fixed-gantry deliveries using 66 h of retrospective tumor motion data from 42 patients treated for thoracic or abdominal cancers. The simulations reveal that using our hybrid approach, a smaller than 1.2 mm or 1.5 mm root-mean-square tracking error can be achieved at a system latency of 310 ms or 460 ms, respectively. Because the kV imaging is only used for a short period of time in our method, extra patient imaging dose can be reduced by an order of magnitude compared to continuous MV-kV imaging, while the clinical tumor targeting accuracy for thoracic or abdominal cancers is maintained. Furthermore, no additional hardware is required with the

  4. Two highly connected POM-based hybrids varying from 2D to 3D: The use of the isomeric ligands

    SciTech Connect

    Zhang Chunjing; Pang Haijun; Hu Mixia; Li Jia; Chen Yaguang

    2009-07-15

    Through employing two isomeric ligands, isonicotinic acid (HINA) and nicotinic acid (HNA), with different electron delocalization nature, two high-dimensional hybrids based on highly connected alpha-metatungstate clusters, [Na{sub 2}(H{sub 2}O){sub 8}Ag{sub 2}(HINA){sub 3}(INA)][Na(H{sub 2}O){sub 2}Ag{sub 2}(HINA){sub 4}(H{sub 2}W{sub 12}O{sub 40})].2H{sub 2}O (1) and [Na{sub 2}(H{sub 2}O){sub 4}Ag{sub 6}(HNA){sub 2}(NA){sub 2}(H{sub 2}W{sub 12}O{sub 40})].8H{sub 2}O (2), have been conventionally synthesized and structurally characterized. 1 exhibits an unusual 1D-in-2D pseudo-polyrotaxane entangled structure, namely, the 2D sheets [Na(H{sub 2}O){sub 2}Ag{sub 2}(HINA){sub 4}(H{sub 2}W{sub 12}O{sub 40})]{sub n}{sup 3n-} are penetrated by enantiomorphous meso-helical chains [Na{sub 2}(H{sub 2}O){sub 8}Ag{sub 2}(HINA){sub 3}(INA)]{sub n}{sup 3n+}. In the 2D sheets, each [H{sub 2}W{sub 12}O{sub 40}]{sup 6-} cluster is surrounded by six Ag and two Na atoms. 2 exhibits a 3D (4, 6)-net structure with (3{sup 2}6{sup 2}7{sup 2})(3{sup 2}4{sup 4}5{sup 4}6{sup 4}7)(3{sup 2}4{sup 4}6{sup 8}7) topology, in which each [H{sub 2}W{sub 12}O{sub 40}]{sup 6-} cluster is connected with ten Ag atoms. These facts indicate that the isomeric ligands play a key role in the formation of final structures. From 1 to 2, the connection number of the [H{sub 2}W{sub 12}O{sub 40}]{sup 6-} cluster changes from 8 to 10 and the dimensionality increases from 2 to 3. Moreover, 1 and 2 display photoluminescent properties in the blue range at room temperature. - Graphical abstract: Two high-dimensional and highly connected alpha-metatungstate-compounds modified by Ag{sup I}-HINA/HNA TMCs were successful obtained and the effect of isomeric organic ligands on the structures was systematically elucidated.

  5. Global 3-D FDTD Maxwell's-Equations Modeling of Ionospheric Disturbances Associated with Earthquakes Using an Optimized Geodesic Grid

    NASA Astrophysics Data System (ADS)

    Simpson, J. J.; Taflove, A.

    2005-12-01

    We report a finite-difference time-domain (FDTD) computational solution of Maxwell's equations [1] that models the possibility of detecting and characterizing ionospheric disturbances above seismic regions. Specifically, we study anomalies in Schumann resonance spectra in the extremely low frequency (ELF) range below 30 Hz as observed in Japan caused by a hypothetical cylindrical ionospheric disturbance above Taiwan. We consider excitation of the global Earth-ionosphere waveguide by lightning in three major thunderstorm regions of the world: Southeast Asia, South America (Amazon region), and Africa. Furthermore, we investigate varying geometries and characteristics of the ionospheric disturbance above Taiwan. The FDTD technique used in this study enables a direct, full-vector, three-dimensional (3-D) time-domain Maxwell's equations calculation of round-the-world ELF propagation accounting for arbitrary horizontal as well as vertical geometrical and electrical inhomogeneities and anisotropies of the excitation, ionosphere, lithosphere, and oceans. Our entire-Earth model grids the annular lithosphere-atmosphere volume within 100 km of sea level, and contains over 6,500,000 grid-points (63 km laterally between adjacent grid points, 5 km radial resolution). We use our recently developed spherical geodesic gridding technique having a spatial discretization best described as resembling the surface of a soccer ball [2]. The grid is comprised entirely of hexagonal cells except for a small fixed number of pentagonal cells needed for completion. Grid-cell areas and locations are optimized to yield a smoothly varying area difference between adjacent cells, thereby maximizing numerical convergence. We compare our calculated results with measured data prior to the Chi-Chi earthquake in Taiwan as reported by Hayakawa et. al. [3]. Acknowledgement This work was suggested by Dr. Masashi Hayakawa, University of Electro-Communications, Chofugaoka, Chofu Tokyo. References [1] A

  6. Facile Fabrication of 3D Layer-by-layer Graphene-gold Nanorod Hybrid Architecture for Hydrogen Peroxide Based Electrochemical Biosensor

    DTIC Science & Technology

    2015-01-01

    Facile fabrication of 3D layer-by-layer graphene-gold nanorod hybrid architecture for hydrogen peroxide based electrochemical biosensor Chenming Xue...the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/3.0/). 1. Introduction Electrochemical biosensors are highly effective in...measurement techniques such as radioisotope tracing, NMR spectroscopy, and microfluorometry assay [12,25,18]. In recent years, electrochemical biosensors

  7. Long-range atmospheric transport of polycyclic aromatic hydrocarbons: a global 3-D model analysis including evaluation of Arctic sources.

    PubMed

    Friedman, Carey L; Selin, Noelle E

    2012-09-04

    We use the global 3-D chemical transport model GEOS-Chem to simulate long-range atmospheric transport of polycyclic aromatic hydrocarbons (PAHs). To evaluate the model's ability to simulate PAHs with different volatilities, we conduct analyses for phenanthrene (PHE), pyrene (PYR), and benzo[a]pyrene (BaP). GEOS-Chem captures observed seasonal trends with no statistically significant difference between simulated and measured mean annual concentrations. GEOS-Chem also captures variability in observed concentrations at nonurban sites (r = 0.64, 0.72, and 0.74, for PHE, PYR, and BaP). Sensitivity simulations suggest snow/ice scavenging is important for gas-phase PAHs, and on-particle oxidation and temperature-dependency of gas-particle partitioning have greater effects on transport than irreversible partitioning or increased particle concentrations. GEOS-Chem estimates mean atmospheric lifetimes of <1 day for all three PAHs. Though corresponding half-lives are lower than the 2-day screening criterion for international policy action, we simulate concentrations at the high-Arctic station of Spitsbergen within four times observed concentrations with strong correlation (r = 0.70, 0.68, and 0.70 for PHE, PYR, and BaP). European and Russian emissions combined account for ~80% of episodic high-concentration events at Spitsbergen.

  8. 3D-hybrid material design with electron/lithium-ion dual-conductivity for high-performance Li-sulfur batteries

    NASA Astrophysics Data System (ADS)

    Zhao, Yan; Tan, Rui; Yang, Jie; Wang, Kai; Gao, Rongtan; Liu, Dong; Liu, Yidong; Yang, Jinlong; Pan, Feng

    2017-02-01

    We report a novel 3D-hybrid cathode material with three-dimensional (3D) N-GO/CNT framework to load sulfur (77.6 wt %), and sulfonated polyaniline (SPANI) of coating layer. Used as a cathode material, it possesses a high capacity (1196 mAh g-1@0.3 A g-1@1.6 mg cm-2), excellent charging-discharging rate (680 mAh g-1@7.5 A g-1) and long-life performance (maintaining 71.1% capacity over 450 cycles), which is mainly attributed to the benefits of excellent electronic/Li-ionic dual-conductivity and confinement effect of the 3D-hybrid N-GO/CNT framework coated by self-doping conducting polymer SPANI. Thus, a 3D sulfur cathode modified with electronic/Li-ionic dual-conduction network can significantly enhance the electrochemical performance and stability, and this novel type of material is very promising for commercial applications that require high energy and power density, long life, and excellent abuse tolerance.

  9. A hybrid 3D spatial access method based on quadtrees and R-trees for globe data

    NASA Astrophysics Data System (ADS)

    Gong, Jun; Ke, Shengnan; Li, Xiaomin; Qi, Shuhua

    2009-10-01

    3D spatial access method for globe data is very crucial technique for virtual earth. This paper presents a brand-new maintenance method to index 3d objects distributed on the whole surface of the earth, which integrates the 1:1,000,000- scale topographic map tiles, Quad-tree and R-tree. Furthermore, when traditional methods are extended into 3d space, the performance of spatial index deteriorates badly, for example 3D R-tree. In order to effectively solve this difficult problem, a new algorithm of dynamic R-tree is put forward, which includes two sub-procedures, namely node-choosing and node-split. In the node-choosing algorithm, a new strategy is adopted, not like the traditional mode which is from top to bottom, but firstly from bottom to top then from top to bottom. This strategy can effectively solve the negative influence of node overlap. In the node-split algorithm, 2-to-3 split mode substitutes the traditional 1-to-2 mode, which can better concern the shape and size of nodes. Because of the rational tree shape, this R-tree method can easily integrate the concept of LOD. Therefore, it will be later implemented in commercial DBMS and adopted in time-crucial 3d GIS system.

  10. Global atmospheric budget of acetaldehyde: 3-D model analysis and constraints from in-situ and satellite observations

    NASA Astrophysics Data System (ADS)

    Millet, D. B.; Guenther, A.; Siegel, D. A.; Nelson, N. B.; Singh, H. B.; de Gouw, J. A.; Warneke, C.; Williams, J.; Eerdekens, G.; Sinha, V.; Karl, T.; Flocke, F.; Apel, E.; Riemer, D. D.; Palmer, P. I.; Barkley, M.

    2010-04-01

    We construct a global atmospheric budget for acetaldehyde using a 3-D model of atmospheric chemistry (GEOS-Chem), and use an ensemble of observations to evaluate present understanding of its sources and sinks. Hydrocarbon oxidation provides the largest acetaldehyde source in the model (128 Tg a-1, a factor of 4 greater than the previous estimate), with alkanes, alkenes, and ethanol the main precursors. There is also a minor source from isoprene oxidation. We use an updated chemical mechanism for GEOS-Chem, and photochemical acetaldehyde yields are consistent with the Master Chemical Mechanism. We present a new approach to quantifying the acetaldehyde air-sea flux based on the global distribution of light absorption due to colored dissolved organic matter (CDOM) derived from satellite ocean color observations. The resulting net ocean emission is 57 Tg a-1, the second largest global source of acetaldehyde. A key uncertainty is the acetaldehyde turnover time in the ocean mixed layer, with quantitative model evaluation over the ocean complicated by known measurement artifacts in clean air. Simulated concentrations in surface air over the ocean generally agree well with aircraft measurements, though the model tends to overestimate the vertical gradient. PAN:NOx ratios are well-simulated in the marine boundary layer, providing some support for the modeled ocean source. We introduce the Model of Emissions of Gases and Aerosols from Nature (MEGANv2.1) for acetaldehyde and ethanol and use it to quantify their net flux from living terrestrial plants. Including emissions from decaying plants the total direct acetaldehyde source from the land biosphere is 23 Tg a-1. Other terrestrial acetaldehyde sources include biomass burning (3 Tg a-1) and anthropogenic emissions (2 Tg a-1). Simulated concentrations in the continental boundary layer are generally unbiased and capture the spatial gradients seen in observations over North America, Europe, and tropical South America. However

  11. Global atmospheric budget of acetaldehyde: 3-D model analysis and constraints from in-situ and satellite observations

    NASA Astrophysics Data System (ADS)

    Millet, D. B.; Guenther, A.; Siegel, D. A.; Nelson, N. B.; Singh, H. B.; de Gouw, J. A.; Warneke, C.; Williams, J.; Eerdekens, G.; Sinha, V.; Karl, T.; Flocke, F.; Apel, E.; Riemer, D. D.; Palmer, P. I.; Barkley, M.

    2009-11-01

    We construct a global atmospheric budget for acetaldehyde using a 3-D model of atmospheric chemistry (GEOS-Chem), and use an ensemble of observations to evaluate present understanding of its sources and sinks. Hydrocarbon oxidation provides the largest acetaldehyde source in the model (130 Tg a-1), with alkanes, alkenes, ethanol, and isoprene the main precursors. We use an updated chemical mechanism for GEOS-Chem, and photochemical acetaldehyde yields are consistent with the Master Chemical Mechanism. We apply SeaWiFS satellite observations to define the global distribution of light absorption due to marine dissolved organic matter (DOM), and estimate the corresponding sea-to-air acetaldehyde flux based on measured photoproduction rates from DOM. The resulting net ocean emission is 58 Tg a-1, the second largest global source of acetaldehyde. Quantitative model evaluation over the ocean is complicated by known measurement artifacts in clean air. Simulated concentrations in surface air over the ocean generally agree well with aircraft measurements, though the model tends to overestimate the vertical gradient. PAN:NOx ratios are well-simulated in the marine boundary layer, providing some support for the modeled ocean source. A key uncertainty is the acetaldehyde turnover time in the ocean mixed layer. We introduce the Model of Emissions of Gases and Aerosols from Nature (MEGANv2.1) for acetaldehyde and ethanol and use it to quantify their net flux from living terrestrial plants. Including emissions from decaying plants the total direct acetaldehyde source from the land biosphere is 22 Tg a-1. Other terrestrial acetaldehyde sources include biomass burning (3 Tg a-1) and anthropogenic emissions (2 Tg a-1). Simulated concentrations in the continental boundary layer are generally unbiased and capture the spatial gradients seen in observations over North America, Europe, and tropical South America. However, the model underestimates acetaldehyde levels in urban outflow

  12. Hybrid biasing approaches for global variance reduction.

    PubMed

    Wu, Zeyun; Abdel-Khalik, Hany S

    2013-02-01

    A new variant of Monte Carlo-deterministic (DT) hybrid variance reduction approach based on Gaussian process theory is presented for accelerating convergence of Monte Carlo simulation and compared with Forward-Weighted Consistent Adjoint Driven Importance Sampling (FW-CADIS) approach implemented in the SCALE package from Oak Ridge National Laboratory. The new approach, denoted the Gaussian process approach, treats the responses of interest as normally distributed random processes. The Gaussian process approach improves the selection of the weight windows of simulated particles by identifying a subspace that captures the dominant sources of statistical response variations. Like the FW-CADIS approach, the Gaussian process approach utilizes particle importance maps obtained from deterministic adjoint models to derive weight window biasing. In contrast to the FW-CADIS approach, the Gaussian process approach identifies the response correlations (via a covariance matrix) and employs them to reduce the computational overhead required for global variance reduction (GVR) purpose. The effective rank of the covariance matrix identifies the minimum number of uncorrelated pseudo responses, which are employed to bias simulated particles. Numerical experiments, serving as a proof of principle, are presented to compare the Gaussian process and FW-CADIS approaches in terms of the global reduction in standard deviation of the estimated responses.

  13. Acoustic and hybrid 3D-printed electrochemical biosensors for the real-time immunodetection of liver cancer cells (HepG2).

    PubMed

    Damiati, Samar; Küpcü, Seta; Peacock, Martin; Eilenberger, Christoph; Zamzami, Mazin; Qadri, Ishtiaq; Choudhry, Hani; Sleytr, Uwe B; Schuster, Bernhard

    2017-03-21

    This study presents an efficient acoustic and hybrid three-dimensional (3D)-printed electrochemical biosensors for the detection of liver cancer cells. The biosensors function by recognizing the highly expressed tumor marker CD133, which is located on the surface of liver cancer cells. Detection was achieved by recrystallizing a recombinant S-layer fusion protein (rSbpA/ZZ) on the surface of the sensors. The fused ZZ-domain enables immobilization of the anti-CD133 antibody in a defined manner. These highly accessible anti-CD133 antibodies were employed as a sensing layer, thereby enabling the efficient detection of liver cancer cells (HepG2). The recognition of HepG2 cells was investigated in situ using a quartz crystal microbalance with dissipation monitoring (QCM-D), which enabled the label-free, real-time detection of living cells on the modified sensor surface under controlled conditions. Furthermore, the hybrid 3D additive printing strategy for biosensors facilitates both rapid development and small-scale manufacturing. The hybrid strategy of combining 3D-printed parts and more traditionally fabricated parts enables the use of optimal materials: a ceramic substrate with noble metals for the sensing element and 3D-printed capillary channels to guide and constrain the clinical sample. Cyclic voltammetry (CV) measurements confirmed the efficiency of the fabricated sensors. Most importantly, these sensors offer low-cost and disposable detection platforms for real-world applications. Thus, as demonstrated in this study, both fabricated acoustic and electrochemical sensing platforms can detect cancer cells and therefore may have further potential in other clinical applications and drug-screening studies.

  14. Towards 3D multi-scale teleseismic and gravity data inversion using hybrid DSM/SPECFEM technique : application to the Pyrenees

    NASA Astrophysics Data System (ADS)

    Martin, Roland; Monteiller, Vadim; Chevrot, Sébastien; Wang, Yi; Komatitsch, Dimitri; Dufréchou, Grégory

    2015-04-01

    We describe here a method of inversion applied to seismic data sets constrained by gravity data at the regional scale. This will allow us to obtain robust models of P and S wave velocities but also of density, providing key constraints on the composition and thermal state of the lithosphere. Our approach relies on teleseimic waves, which illuminate the medium from below. We have developped a hybrid method in which a wave propagation method at the global scale (DSM/Direct solution method) is coupled with a spectral element method at the regional scale (Monteiller et al. 2013). With the spectral element method, we are able to model the 3D wave propagation effects in a computational domain of 400km long x 400km wide and 200 km deep, for an incident teleseismic wavefront introduced at the boundaries of this domain with periods as short as 2 s. The DSM global method allows to compute this incident field for a spherical Earth model. We use a multi-scale joint inversion of both gravity and seismic waveform data, accounting for the long wavelengths of the gravity field taken from a global model. In terms of inversion technique, we have validated an adjoint method for the inversion of seismic waveforms. An optimized BFGS inversion technique is used to minimize the difference between observed and computed full waveforms. The gradient of the misfit function gives the direction over which the model must be perturbed to minimize this difference. At each step of the inversion procedure we choose an optimal step length that accelerates the minimization. This is the crucial ingredient that allows us to build an efficient iterative full waveform inversion. We have extended this method by incorporating gravity data provided by the BGI/Bureau Gravimétrique International into the inversion. If the waveforms allow us to constrain the seismic velocities, they are less sensitive to the structure in density, which gives independent and crucial information to constrain the nature of rocks

  15. Modelling of Criegee Intermediates using the 3-D global model, STOCHEM-CRI and investigating their global impacts on Secondary Organic Aerosol formation

    NASA Astrophysics Data System (ADS)

    Khan, M. Anwar H.; Cooke, Michael; Utembe, Steve; Archibald, Alexander; Derwent, Richard; Jenkin, Mike; Lyons, Kyle; Kent, Adam; Percival, Carl; Shallcross, Dudley E.

    2016-04-01

    Gas phase reactions of ozone with unsaturated compounds form stabilized Criegee intermediates (sCI) which play an important role in controlling the budgets of many tropospheric species including OH, organic acids and secondary organic aerosols (SOA). Recently sCI has been proposed to play a significant role in atmospheric sulfate and nitrate chemistry by forming sulfuric acid (promoter of aerosol formation) and nitrate radical (a powerful oxidizing agent). sCI can also undergo association reactions with water, alcohols, and carboxylic acids to form hydroperoxides and with aldehydes and ketones to form secondary ozonides. The products from these reactions are low volatility compounds which can contribute to the formation of SOA. The importance of plant emitted alkenes (isoprene, monoterpenes, sesquiterpenes) in the production of SOA through sCI formation have already been investigated in laboratory studies. However, the SOA formation from these reactions are absent in current global models. Thus, the formation of SOA has been incorporated in the global model, STOCHEM-CRI, a 3-D global chemistry transport model and the role of CI chemistry in controlling atmospheric composition and climate, and the influence of water vapor has been discussed in the study.

  16. Exploring the diversity of climates on terrestrial exoplanets using a generic 3D Global Climate Model (Invited)

    NASA Astrophysics Data System (ADS)

    Forget, F.; Leconte, J.; Wordsworth, R.; Millour, E.; Charnay, B.

    2013-12-01

    What kind of environment may exist on terrestrial planets around other stars? In spite of the lack of direct observations, it may not be premature to speculate on the possible exoplanetary climates, for instance to optimize future telescopic observations, or to assess the probability of habitable worlds in the galaxy. A first major question is to imagine the possible atmospheric composition surface volatile inventory. This depends on complex processes which are difficult to model: origins of volatile, atmospheric escape, geochemistry, long-term photochemistry. However, assuming that the atmosphere is known, the possible climates on a given planet around a given star can be explored using 3D Global Climate Models (GCMs) analogous to the ones developed to simulate the Earth climate as well as the other telluric atmospheres in the solar system. Our experience with the Earth, Mars, Titan and Venus suggests that relatively complete and realistic climate simulators can be developed by combining a few components like a dynamical core, a radiative transfer solver, a parametrisation of subgrid- scale turbulence and convection, a thermal ground model, and a volatile phase change code. Solar system GCMs successes and failure also teach us that when modeling climate systems which are poorly observed, it is necessary to carefully explore the sensitivity of the modeled system to key parameters, in order to 'bracket' the reality We will present several examples of studies recently performed using a 'generic' Global Climate Model that we have developed in the past few years, in particular to better understand the processes which controls the stability of liquid water on a planetary surface and its habitability. Climate models confirm that planetary climates primarily depends on 1) The atmospheric composition and mass and the surface volatile inventory 2) The incident stellar flux 3) The tidal evolution of the planetary spin, which can notably lock a planet with a permanent night

  17. A hybrid approach for fusing 4D-MRI temporal information with 3D-CT for the study of lung and lung tumor motion

    SciTech Connect

    Yang, Y. X.; Van Reeth, E.; Poh, C. L.; Teo, S.-K.; Tan, C. H.; Tham, I. W. K.

    2015-08-15

    Purpose: Accurate visualization of lung motion is important in many clinical applications, such as radiotherapy of lung cancer. Advancement in imaging modalities [e.g., computed tomography (CT) and MRI] has allowed dynamic imaging of lung and lung tumor motion. However, each imaging modality has its advantages and disadvantages. The study presented in this paper aims at generating synthetic 4D-CT dataset for lung cancer patients by combining both continuous three-dimensional (3D) motion captured by 4D-MRI and the high spatial resolution captured by CT using the authors’ proposed approach. Methods: A novel hybrid approach based on deformable image registration (DIR) and finite element method simulation was developed to fuse a static 3D-CT volume (acquired under breath-hold) and the 3D motion information extracted from 4D-MRI dataset, creating a synthetic 4D-CT dataset. Results: The study focuses on imaging of lung and lung tumor. Comparing the synthetic 4D-CT dataset with the acquired 4D-CT dataset of six lung cancer patients based on 420 landmarks, accurate results (average error <2 mm) were achieved using the authors’ proposed approach. Their hybrid approach achieved a 40% error reduction (based on landmarks assessment) over using only DIR techniques. Conclusions: The synthetic 4D-CT dataset generated has high spatial resolution, has excellent lung details, and is able to show movement of lung and lung tumor over multiple breathing cycles.

  18. Global existence and asymptotic behavior for the 3D compressible Navier-Stokes equations without heat conductivity in a bounded domain

    NASA Astrophysics Data System (ADS)

    Wu, Guochun

    2017-01-01

    In this paper, we investigate the global existence and uniqueness of strong solutions to the initial boundary value problem for the 3D compressible Navier-Stokes equations without heat conductivity in a bounded domain with slip boundary. The global existence and uniqueness of strong solutions are obtained when the initial data is near its equilibrium in H2 (Ω). Furthermore, the exponential convergence rates of the pressure and velocity are also proved by delicate energy methods.

  19. Test results of the first 3D-IC prototype chip developed in the framework of HL-LHC/ATLAS hybrid pixel upgrade

    NASA Astrophysics Data System (ADS)

    Pangaud, P.; Arutinov, D.; Barbero, M.; Bompard, F.; Breugnon, P.; Clemens, J.-C.; Fougeron, D.; Garcia-Sciveres, M.; Godiot, S.; Hemperek, T.; Krüger, H.; Obermann, T.; Rozanov, S.; Wermes, N.

    2014-02-01

    To face new challenges brought by the upgrades of the Large Hadron Collider at CERN and of the ATLAS pixels detector, for which high spatial resolution, very good signal to noise ratio and high radiation hardness is needed, 3D integrated technologies are investigated. In the years to come, the Large Hadron Collider will be upgraded to Higher Luminosity (HL-LHC). The ATLAS pixel detector needs to handle this new challenging environment. As a consequence, 3D integrated technologies are pursued with the target of offering higher spatial resolution, very good signal to noise ratio and unprecedented radiation hardness. We present here the test results of the first 3D prototype chip developed in the GlobalFoundries 130 nm technology processed by the Tezzaron Company, submitted within the 3D-IC consortium for which a qualification program was developed. Reliability and influence on the behavior of the integrated devices due to the presence of the Bond Interface (BI) and of the Through Silicon Via (TSV) connections, both needed for the 3D integration process, have also been addressed by the tests.

  20. The hybridizations of cobalt 3 d bands with the electron band structure of the graphene/cobalt interface on a tungsten substrate

    NASA Astrophysics Data System (ADS)

    Hwang, Jinwoong; Hwang, Choongyu; Chung, Nak-Kwan; N'Diaye, A. D.; Schmid, A. K.; Denlinger, Jonathan

    2016-08-01

    The interface between graphene and a ferromagnetic substrate has attracted recent research interests due to its potential for spintronic applications. We report an angle-resolved photoemission spectroscopy study on the interface between graphene and cobalt epitaxially grown on a tungsten substrate. We find that the electron band structure of the interface exhibits clear discontinuities at the crossing points with cobalt 3 d bands. These observations indicate strong hybridizations between the electronic states in the interface and provide an important clue to understand the intriguing electromagnetic properties of the graphene/ferromagnet interface.

  1. Co(OH)2 @PANI Hybrid Nanosheets with 3D Networks as High-Performance Electrocatalysts for Hydrogen Evolution Reaction.

    PubMed

    Feng, Jin-Xian; Ding, Liang-Xin; Ye, Sheng-Hua; He, Xu-Jun; Xu, Han; Tong, Ye-Xiang; Li, Gao-Ren

    2015-11-25

    Hybrid electrocatalysts with excellent electrocatalytic activity for hydrogen reduction are fabricated using an efficient and facile electrochemical route. The electronic and synergistic effects between Co(OH)2 and polyaniline (PANI) in the composite structure are the key factors that generate the high electrocatalytic activity and excellent stability. A highly efficient, non-precious metal-based flexible electrocatalyst for high-performance electrocatalysts is shown, which reveals a novel route for the design and synthesis of electrocatalysts.

  2. Self-assembly and morphology change of four organic-polyoxometalate hybrids with different solid structures from 2D lamellar to 3D hexagonal forms

    NASA Astrophysics Data System (ADS)

    TAN, Chunxia

    2017-02-01

    A series of organic-polyoxometalate hybrids L-EuW11, L-EuW10, L-EuW22 and L-Mo132 were fabricated by the same organic cations with different polyoxometalate anions from K5[Eu(SiW11O39)(H2O)2], K13[Eu(SiW11O39)2]·15H2O, Na9[EuW10O36]·36H2O to "Keplerate" -type (NH4)72[Mo132O372(SO4)30(H2O)72]. The structures of hybrids were characterized by elemental analysis, thermogravimetric analysis (TGA), infrared spectra (IR) and small-angle X-ray scattering (SAXS). Self-assembly behaviors and aggregates morphology of these hybrids in mixed solution of chloroform-methanol are obtained by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). L-EuW11, L-EuW10 and L-EuW22 have different aggregation morphology but the similarly layered structures. Micron-sized vesicular structures of L-Mo132 rupture in solvent and eventually turn into approximate hexagon. SAXS analysis of L-EuW11, L-EuW10 and L-EuW22 shows that these hybrids aggregates change from two-dimensional (2D) lamellar to three-dimensional (3D) hexagonal structure in solid state.

  3. 3D electrostatic gyrokinetic electron and fully kinetic ion simulation of lower-hybrid drift instability of Harris current sheet

    DOE PAGES

    Wang, Zhenyu; Lin, Yu; Wang, Xueyi; ...

    2016-07-07

    The eigenmode stability properties of three-dimensional lower-hybrid-drift-instabilities (LHDI) in a Harris current sheet with a small but finite guide magnetic field have been systematically studied by employing the gyrokinetic electron and fully kinetic ion (GeFi) particle-in-cell (PIC) simulation model with a realistic ion-to-electron mass ratio mi/me. In contrast to the fully kinetic PIC simulation scheme, the fast electron cyclotron motion and plasma oscillations are systematically removed in the GeFi model, and hence one can employ the realistic mi/me. The GeFi simulations are benchmarked against and show excellent agreement with both the fully kinetic PIC simulation and the analytical eigenmode theory. Our studies indicate that, for small wavenumbers, ky, along the current direction, the most unstable eigenmodes are peaked at the location wheremore » $$\\vec{k}$$• $$\\vec{B}$$ =0, consistent with previous analytical and simulation studies. Here, $$\\vec{B}$$ is the equilibrium magnetic field and $$\\vec{k}$$ is the wavevector perpendicular to the nonuniformity direction. As ky increases, however, the most unstable eigenmodes are found to be peaked at $$\\vec{k}$$ •$$\\vec{B}$$ ≠0. Additionally, the simulation results indicate that varying mi/me, the current sheet width, and the guide magnetic field can affect the stability of LHDI. Simulations with the varying mass ratio confirm the lower hybrid frequency and wave number scalings.« less

  4. 3D electrostatic gyrokinetic electron and fully kinetic ion simulation of lower-hybrid drift instability of Harris current sheet

    NASA Astrophysics Data System (ADS)

    Wang, Zhenyu; Lin, Yu; Wang, Xueyi; Tummel, Kurt; Chen, Liu

    2016-07-01

    The eigenmode stability properties of three-dimensional lower-hybrid-drift-instabilities (LHDI) in a Harris current sheet with a small but finite guide magnetic field have been systematically studied by employing the gyrokinetic electron and fully kinetic ion (GeFi) particle-in-cell (PIC) simulation model with a realistic ion-to-electron mass ratio mi/me . In contrast to the fully kinetic PIC simulation scheme, the fast electron cyclotron motion and plasma oscillations are systematically removed in the GeFi model, and hence one can employ the realistic mi/me . The GeFi simulations are benchmarked against and show excellent agreement with both the fully kinetic PIC simulation and the analytical eigenmode theory. Our studies indicate that, for small wavenumbers, ky, along the current direction, the most unstable eigenmodes are peaked at the location where k →.B → =0 , consistent with previous analytical and simulation studies. Here, B → is the equilibrium magnetic field and k → is the wavevector perpendicular to the nonuniformity direction. As ky increases, however, the most unstable eigenmodes are found to be peaked at k →.B → ≠0 . In addition, the simulation results indicate that varying mi/me , the current sheet width, and the guide magnetic field can affect the stability of LHDI. Simulations with the varying mass ratio confirm the lower hybrid frequency and wave number scalings.

  5. Construction of a 3D rGO-collagen hybrid scaffold for enhancement of the neural differentiation of mesenchymal stem cells

    NASA Astrophysics Data System (ADS)

    Guo, Weibo; Wang, Shu; Yu, Xin; Qiu, Jichuan; Li, Jianhua; Tang, Wei; Li, Zhou; Mou, Xiaoning; Liu, Hong; Wang, Zhonglin

    2016-01-01

    The cell-material interface is one of the most important considerations in designing a high-performance tissue engineering scaffold because the surface of the scaffold can determine the fate of stem cells. A conductive surface is required for a scaffold to direct stem cells toward neural differentiation. However, most conductive polymers are toxic and not amenable to biological degradation, which restricts the design of neural tissue engineering scaffolds. In this study, we used a bioactive three-dimensional (3D) porcine acellular dermal matrix (PADM), which is mainly composed of type I collagen, as a basic material and successfully assembled a layer of reduced graphene oxide (rGO) nanosheets on the surface of the PADM channels to obtain a porous 3D, biodegradable, conductive and biocompatible PADM-rGO hybrid neural tissue engineering scaffold. Compared with the PADM scaffold, assembling the rGO into the scaffold did not induce a significant change in the microstructure but endowed the PADM-rGO hybrid scaffold with good conductivity. A comparison of the neural differentiation of rat bone-marrow-derived mesenchymal stem cells (MSCs) was performed by culturing the MSCs on PADM and PADM-rGO scaffolds in neuronal culture medium, followed by the determination of gene expression and immunofluorescence staining. The results of both the gene expression and protein level assessments suggest that the rGO-assembled PADM scaffold may promote the differentiation of MSCs into neuronal cells with higher protein and gene expression levels after 7 days under neural differentiation conditions. This study demonstrated that the PADM-rGO hybrid scaffold is a promising scaffold for neural tissue engineering; this scaffold can not only support the growth of MSCs at a high proliferation rate but also enhance the differentiation of MSCs into neural cells.The cell-material interface is one of the most important considerations in designing a high-performance tissue engineering scaffold

  6. 3D electrostatic gyrokinetic electron and fully kinetic ion simulation of lower-hybrid drift instability of Harris current sheet

    SciTech Connect

    Wang, Zhenyu; Lin, Yu; Wang, Xueyi; Tummel, Kurt; Chen, Liu

    2016-07-07

    The eigenmode stability properties of three-dimensional lower-hybrid-drift-instabilities (LHDI) in a Harris current sheet with a small but finite guide magnetic field have been systematically studied by employing the gyrokinetic electron and fully kinetic ion (GeFi) particle-in-cell (PIC) simulation model with a realistic ion-to-electron mass ratio mi/me. In contrast to the fully kinetic PIC simulation scheme, the fast electron cyclotron motion and plasma oscillations are systematically removed in the GeFi model, and hence one can employ the realistic mi/me. The GeFi simulations are benchmarked against and show excellent agreement with both the fully kinetic PIC simulation and the analytical eigenmode theory. Our studies indicate that, for small wavenumbers, ky, along the current direction, the most unstable eigenmodes are peaked at the location where $\\vec{k}$• $\\vec{B}$ =0, consistent with previous analytical and simulation studies. Here, $\\vec{B}$ is the equilibrium magnetic field and $\\vec{k}$ is the wavevector perpendicular to the nonuniformity direction. As ky increases, however, the most unstable eigenmodes are found to be peaked at $\\vec{k}$ •$\\vec{B}$ ≠0. Additionally, the simulation results indicate that varying mi/me, the current sheet width, and the guide magnetic field can affect the stability of LHDI. Simulations with the varying mass ratio confirm the lower hybrid frequency and wave number scalings.

  7. Jovian Plasmas Torus Interaction with Europa. Plasma Wake Structure and Effect of Inductive Magnetic Field: 3D Hybrid Kinetic Simulation

    NASA Technical Reports Server (NTRS)

    Lipatov, A. S.; Cooper, J F.; Paterson, W. R.; Sittler, E. C., Jr.; Hartle, R. E.; Simpson, David G.

    2013-01-01

    The hybrid kinetic model supports comprehensive simulation of the interaction between different spatial and energetic elements of the Europa moon-magnetosphere system with respect to a variable upstream magnetic field and flux or density distributions of plasma and energetic ions, electrons, and neutral atoms. This capability is critical for improving the interpretation of the existing Europa flyby measurements from the Galileo Orbiter mission, and for planning flyby and orbital measurements (including the surface and atmospheric compositions) for future missions. The simulations are based on recent models of the atmosphere of Europa (Cassidy et al., 2007; Shematovich et al., 2005). In contrast to previous approaches with MHD simulations, the hybrid model allows us to fully take into account the finite gyroradius effect and electron pressure, and to correctly estimate the ion velocity distribution and the fluxes along the magnetic field (assuming an initial Maxwellian velocity distribution for upstream background ions). Photoionization, electron-impact ionization, charge exchange and collisions between the ions and neutrals are also included in our model. We consider the models with Oþ þ and Sþ þ background plasma, and various betas for background ions and electrons, and pickup electrons. The majority of O2 atmosphere is thermal with an extended non-thermal population (Cassidy et al., 2007). In this paper, we discuss two tasks: (1) the plasma wake structure dependence on the parameters of the upstream plasma and Europa's atmosphere (model I, cases (a) and (b) with a homogeneous Jovian magnetosphere field, an inductive magnetic dipole and high oceanic shell conductivity); and (2) estimation of the possible effect of an induced magnetic field arising from oceanic shell conductivity. This effect was estimated based on the difference between the observed and modeled magnetic fields (model II, case (c) with an inhomogeneous Jovian magnetosphere field, an inductive

  8. Hybrid local FEM/global LISA modeling of damped guided wave propagation in complex composite structures

    NASA Astrophysics Data System (ADS)

    Shen, Yanfeng; Cesnik, Carlos E. S.

    2016-09-01

    This paper presents a new hybrid modeling technique for the efficient simulation of guided wave generation, propagation, and interaction with damage in complex composite structures. A local finite element model is deployed to capture the piezoelectric effects and actuation dynamics of the transmitter, while the global domain wave propagation and interaction with structural complexity (structure features and damage) are solved utilizing a local interaction simulation approach (LISA). This hybrid approach allows the accurate modeling of the local dynamics of the transducers and keeping the LISA formulation in an explicit format, which facilitates its readiness for parallel computing. The global LISA framework was extended through the 3D Kelvin-Voigt viscoelasticity theory to include anisotropic damping effects for composite structures, as an improvement over the existing LISA formulation. The global LISA framework was implemented using the compute unified device architecture running on graphic processing units. A commercial preprocessor is integrated seamlessly with the computational framework for grid generation and material property allocation to handle complex structures. The excitability and damping effects are successfully captured by this hybrid model, with experimental validation using the scanning laser doppler vibrometry. To demonstrate the capability of our hybrid approach for complex structures, guided wave propagation and interaction with a delamination in a composite panel with stiffeners is presented.

  9. Micromechanics of Amorphous Metal/Polymer Hybrid Structures with 3D Cellular Architectures: Size Effects, Buckling Behavior, and Energy Absorption Capability.

    PubMed

    Mieszala, Maxime; Hasegawa, Madoka; Guillonneau, Gaylord; Bauer, Jens; Raghavan, Rejin; Frantz, Cédric; Kraft, Oliver; Mischler, Stefano; Michler, Johann; Philippe, Laetitia

    2017-02-01

    By designing advantageous cellular geometries and combining the material size effects at the nanometer scale, lightweight hybrid microarchitectured materials with tailored structural properties are achieved. Prior studies reported the mechanical properties of high strength cellular ceramic composites, obtained by atomic layer deposition. However, few studies have examined the properties of similar structures with metal coatings. To determine the mechanical performance of polymer cellular structures reinforced with a metal coating, 3D laser lithography and electroless deposition of an amorphous layer of nickel-boron (NiB) is used for the first time to produce metal/polymer hybrid structures. In this work, the mechanical response of microarchitectured structures is investigated with an emphasis on the effects of the architecture and the amorphous NiB thickness on their deformation mechanisms and energy absorption capability. Microcompression experiments show an enhancement of the mechanical properties with the NiB thickness, suggesting that the deformation mechanism and the buckling behavior are controlled by the brittle-to-ductile transition in the NiB layer. In addition, the energy absorption properties demonstrate the possibility of tuning the energy absorption efficiency with adequate designs. These findings suggest that microarchitectured metal/polymer hybrid structures are effective in producing materials with unique property combinations.

  10. Critical factors affecting the 3D microstructural formation in hybrid conductive adhesive materials studied by X-ray nano-tomography

    NASA Astrophysics Data System (ADS)

    Chen-Wiegart, Yu-Chen Karen; Figueroa-Santos, Miriam Aileen; Petrash, Stanislas; Garcia-Miralles, Jose; Wang, Jun

    2014-12-01

    Conductive adhesives are found favorable in a wide range of applications including a lead-free solder in micro-chips, flexible and printable electronics and enhancing the performance of energy storage devices. Composite materials comprised of metallic fillers and a polymer matrix are of great interest to be implemented as hybrid conductive adhesives. Here we investigated a cost-effective conductive adhesive material consisting of silver-coated copper as micro-fillers using synchrotron-based three-dimensional (3D) X-ray nano-tomography. The key factors affecting the quality and performance of the material were quantitatively studied in 3D on the nanometer scale for the first time. A critical characteristic parameter, defined as a shape-factor, was determined to yield a high-quality silver coating, leading to satisfactory performance. A `stack-and-screen' mechanism was proposed to elaborate such a phenomenon. The findings and the technique developed in this work will facilitate the future advancement of conductive adhesives to have a great impact in micro-electronics and other applications.Conductive adhesives are found favorable in a wide range of applications including a lead-free solder in micro-chips, flexible and printable electronics and enhancing the performance of energy storage devices. Composite materials comprised of metallic fillers and a polymer matrix are of great interest to be implemented as hybrid conductive adhesives. Here we investigated a cost-effective conductive adhesive material consisting of silver-coated copper as micro-fillers using synchrotron-based three-dimensional (3D) X-ray nano-tomography. The key factors affecting the quality and performance of the material were quantitatively studied in 3D on the nanometer scale for the first time. A critical characteristic parameter, defined as a shape-factor, was determined to yield a high-quality silver coating, leading to satisfactory performance. A `stack-and-screen' mechanism was proposed to

  11. A 3D Hybrid Model for Tissue Growth: The Interplay between Cell Population and Mass Transport Dynamics

    PubMed Central

    Cheng, Gang; Markenscoff, Pauline; Zygourakis, Kyriacos

    2009-01-01

    Abstract To provide theoretical guidance for the design and in vitro cultivation of bioartificial tissues, we have developed a multiscale computational model that can describe the complex interplay between cell population and mass transport dynamics that governs the growth of tissues in three-dimensional scaffolds. The model has three components: a transient partial differential equation for the simultaneous diffusion and consumption of a limiting nutrient; a cellular automaton describing cell migration, proliferation, and collision; and equations that quantify how the varying nutrient concentration modulates cell division and migration. The hybrid discrete-continuous model was parallelized and solved on a distributed-memory multicomputer to study how transport limitations affect tissue regeneration rates under conditions encountered in typical bioreactors. Simulation results show that the severity of transport limitations can be estimated by the magnitude of two dimensionless groups: the Thiele modulus and the Biot number. Key parameters including the initial seeding mode, cell migration speed, and the hydrodynamic conditions in the bioreactor are shown to affect not only the overall rate, but also the pattern of tissue growth. This study lays the groundwork for more comprehensive models that can handle mixed cell cultures, multiple nutrients and growth factors, and other cellular processes, such as cell death. PMID:19619455

  12. Origin of Mercury’s double magnetopause: 3D hybrid simulation study with A.I.K.E.F.

    NASA Astrophysics Data System (ADS)

    Müller, Joachim; Simon, Sven; Wang, Yung-Ching; Motschmann, Uwe; Heyner, Daniel; Schüle, Josef; Ip, Wing-Huen; Kleindienst, Gero; Pringle, Gavin J.

    2012-03-01

    During the first and second Mercury flyby the MESSENGER spacecraft detected a dawn side double-current sheet inside the Hermean magnetosphere that was labeled the “double magnetopause” (Slavin, J.A. et al. [2008]. Science 321, 85). This double current sheet confines a region of decreased magnetic field that is referred to as Mercury’s “dayside boundary layer” (Anderson, M., Slavin, J., Horth, H. [2011]. Planet. Space Sci.). Up to the present day the double current sheet, the boundary layer and the key processes leading to their formation are not well understood. In order to advance the understanding of this region we have carried out self-consistent plasma simulations of the Hermean magnetosphere by means of the hybrid simulation code A.I.K.E.F. (Müller, J., Simon, S., Motschmann, U., Schüle, J., Glassmeier, K., Pringle, G.J. [2011]. Comput. Phys. Commun. 182, 946-966). Magnetic field and plasma results are in excellent agreement with the MESSENGER observations. In contrast to former speculations our results prove this double current sheet may exist in a pure solar wind hydrogen plasma, i.e. in the absence of any exospheric ions like sodium. Both currents are similar in orientation but the outer is stronger in intensity. While the outer current sheet can be considered the “classical” magnetopause, the inner current sheet between the magnetopause and Mercury’s surface reveals to be sustained by a diamagnetic current that originates from proton pressure gradients at Mercury’s inner magnetosphere. The pressure gradients in turn exist due to protons that are trapped on closed magnetic field lines and mirrored between north and south pole. Both, the dayside and nightside diamagnetic decreases that have been observed during the MESSENGER mission show to be direct consequences of this diamagnetic current that we label Mercury’s “boundary-layer-current“.

  13. Time-Dependent Distribution Functions in C-Mod Calculated with the CQL3D-Hybrid-FOW, AORSA Full-Wave, and DC Lorentz Codes

    NASA Astrophysics Data System (ADS)

    Harvey, R. W. (Bob); Petrov, Yu. V.; Jaeger, E. F.; Berry, L. A.; Bonoli, P. T.; Bader, A.

    2015-11-01

    A time-dependent simulation of C-Mod pulsed ICRF power is made calculating minority hydrogen ion distribution functions with the CQL3D-Hybrid-FOW finite-orbit-width Fokker-Planck code. ICRF fields are calculated with the AORSA full wave code, and RF diffusion coefficients are obtained from these fields using the DC Lorentz gyro-orbit code. Prior results with a zero-banana-width simulation using the CQL3D/AORSA/DC time-cycles showed a pronounced enhancement of the H distribution in the perpendicular velocity direction compared to results obtained from Stix's quasilinear theory, in general agreement with experiment. The present study compares the new FOW results, including relevant gyro-radius effects, to determine the importance of these effects on the the NPA synthetic diagnostic time-dependence. The new NPA results give increased agreement with experiment, particularly in the ramp-down time after the ICRF pulse. Funded, through subcontract with Massachusetts Institute of Technology, by USDOE sponsored SciDAC Center for Simulation of Wave-Plasma Interactions.

  14. Hybrid Macro-Porous Titanium Ornamented by Degradable 3D Gel/nHA Micro-Scaffolds for Bone Tissue Regeneration

    PubMed Central

    Yin, Bo; Ma, Pei; Chen, Jun; Wang, Hai; Wu, Gui; Li, Bo; Li, Qiang; Huang, Zhifeng; Qiu, Guixing; Wu, Zhihong

    2016-01-01

    Porous titanium is a kind of promising material for bone substitution, while its bio-inert property results in demand of modifications to improve the osteointegration capacity. In this study, gelatin (Gel) and nano-hydroxyapatite (nHA) were used to construct 3D micro-scaffolds in the pores of porous titanium in the ratios of Gel:nHA = 1:0, Gel:nHA = 1:1, and Gel:nHA = 1:3, respectively. Cell attachment and proliferation, and gene and protein expression levels of osteogenic markers were evaluated in MC3T3-E1 cells, followed by bone regeneration assessment in a rabbit radius defect model. All hybrid scaffolds with different composition ratio were found to have significant promotional effects in cell adhesion, proliferation and differentiation, in which the group with Gel:nHA = 1:1 showed the best performance in vitro, as well as the most bone regeneration volume in vivo. This 3D micro-scaffolds modification may be an innovative method for porous titanium ornamentation and shows potential application values in clinic. PMID:27092492

  15. Accurate and Fully Automatic Hippocampus Segmentation Using Subject-Specific 3D Optimal Local Maps Into a Hybrid Active Contour Model

    PubMed Central

    Gkontra, Polyxeni; Daras, Petros; Maglaveras, Nicos

    2014-01-01

    Assessing the structural integrity of the hippocampus (HC) is an essential step toward prevention, diagnosis, and follow-up of various brain disorders due to the implication of the structural changes of the HC in those disorders. In this respect, the development of automatic segmentation methods that can accurately, reliably, and reproducibly segment the HC has attracted considerable attention over the past decades. This paper presents an innovative 3-D fully automatic method to be used on top of the multiatlas concept for the HC segmentation. The method is based on a subject-specific set of 3-D optimal local maps (OLMs) that locally control the influence of each energy term of a hybrid active contour model (ACM). The complete set of the OLMs for a set of training images is defined simultaneously via an optimization scheme. At the same time, the optimal ACM parameters are also calculated. Therefore, heuristic parameter fine-tuning is not required. Training OLMs are subsequently combined, by applying an extended multiatlas concept, to produce the OLMs that are anatomically more suitable to the test image. The proposed algorithm was tested on three different and publicly available data sets. Its accuracy was compared with that of state-of-the-art methods demonstrating the efficacy and robustness of the proposed method. PMID:27170866

  16. The Interaction of the Solar Wind with Solar Probe Plus - 3D Hybrid Simulation. Report 1; The Study for the Distance 4.5Rs

    NASA Technical Reports Server (NTRS)

    Lipatov, Alexander S.; Sittler, Edward C.; Hartle, Richard E.; Cooper, John F.

    2010-01-01

    Our report devotes a 3D numerical hybrid model of the interaction of the solar wind with the Solar Probe spacecraft. The SPP model includes 3 main parts, namely, a non-conducting heat shield, a support system, and cylindrical section or spacecraft bus that contains the particle analysis devices and antenna. One observes an excitation of the low frequency Alfven and whistler type wave directed by the magnetic field with an amplitude of about (0.06-0.6) V/m. The compression waves and the jumps in an electric field with an amplitude of about (0.15-0.7) V/m were also observed. The wave amplitudes are comparable to or greater than previously estimated max wave amplitudes that SPP is expected to measure. The results of our hybrid simulation will be useful for understanding the plasma environment near the SPP spacecraft at the distance 4.5 Rs. Future simulation will take into account the charging of the spacecraft, the charge separation effects, an outgassing from heat shield, a photoionization and an electron impact ionization effects near the spacecraft.

  17. The Interaction of the Solar Wind with Solar Probe Plus - 3D Hybrid Simulation. Report 1; The Study for the Distance 4.5Rs

    NASA Technical Reports Server (NTRS)

    Lipatov, Alexander S.; Sittler, Edward C.; Hartle, Richard E.; Cooper, John F.

    2010-01-01

    Our report devotes a 3D numerical hybrid model of the interaction of the solar wind with the Solar Probe spacecraft. The Solar Probe Plus (SPP) model includes 3 main parts, namely, a non-conducting heat shield, a support system, and cylindrical section or spacecraft bus that contains the particle analysis devices and antenna. One observes an excitation of the low frequency Alfven and whistler type wave directed by the magnetic field with an amplitude of about (0.06-0.6) V/m. The compression waves and the jumps in an electric field with an amplitude of about (0.15-0.7) V/m were also observed. The wave amplitudes are comparable to or greater than previously estimated max wave amplitudes that SPP is expected to measure. The results of our hybrid simulation will be useful for understanding the plasma environment near the SPP spacecraft at the distance 4.5 Rs. Future simulation will take into account the charging of the spacecraft, the charge separation effects, an outgassing from heat shield, a photoionization and an electron impact ionization effects near the spacecraft.

  18. Background and Pickup Ion Velocity Distribution Dynamics in Titan's Plasma Environment: 3D Hybrid Simulation and Comparison with CAPS T9 Observations

    NASA Technical Reports Server (NTRS)

    Lipatov, A. S.; Sittler, E. C., Jr.; Hartle, R. E.; Cooper, J. F.; Simpson, D. G.

    2011-01-01

    In this report we discuss the ion velocity distribution dynamics from the 3D hybrid simulation. In our model the background, pickup, and ionospheric ions are considered as a particles, whereas the electrons are described as a fluid. Inhomogeneous photoionization, electron-impact ionization and charge exchange are included in our model. We also take into account the collisions between the ions and neutrals. The current simulation shows that mass loading by pickup ions H(+); H2(+), CH4(+) and N2(+) is stronger than in the previous simulations when O+ ions are introduced into the background plasma. In our hybrid simulations we use Chamberlain profiles for the atmospheric components. We also include a simple ionosphere model with average mass M = 28 amu ions that were generated inside the ionosphere. The moon is considered as a weakly conducting body. Special attention will be paid to comparing the simulated pickup ion velocity distribution with CAPS T9 observations. Our simulation shows an asymmetry of the ion density distribution and the magnetic field, including the formation of the Alfve n wing-like structures. The simulation also shows that the ring-like velocity distribution for pickup ions relaxes to a Maxwellian core and a shell-like halo.

  19. Results of the implementation on a mock-up of the full 3dB hybrid matching option of the ITER ICRH system

    SciTech Connect

    Grine, D.; Vervier, M.; Messiaen, A.; Dumortier, P.

    2011-12-23

    Each of the two ICRH antennas for ITER must couple 20MW to the plasma in the 40-55MHz band via an array of 24 radiating shorted straps fed by four generators. The matching system must provide automatic matching control on the mean load provided by the plasma and be resilient (parallel {Gamma}{sub G} parallel <0.2) to a wide range of fast antenna load excursions occurring in ELMy plasmas. Furthermore, good control of the current distribution in the strap array must be possible for the various heating and current drive scenarios. Two load resilient matching options have been considered for ITER: the 4 'Conjugate-T'(CT) and the 4 hybrids ones, the first being presently considered as a back-up option. Automatic control of these 2 options has been developed, and tested for optimization on a low-powered scaled mock-up. Successful implementation of the simultaneous feedback control of 11 actuators for the matching of the 4 CT and for the control of the toroidal phasing has already been achieved. The matching and the array current control of the 3dB hybrid option are provided by simultaneous feedback control of the decouplers and double stub tuners (in total 23 actuators) and this has also been successfully achieved for the full array. The paper discusses the circuit implementation and presents the obtained results.

  20. Towards global scale coastal flood hazard in Delta Cities with 30-meter SRTM and 3D_i

    NASA Astrophysics Data System (ADS)

    Winsemius, Hessel; Verhoeven, Govert; Van Leeuwen, Elgard; Van der Klis, Hanneke; Van Wesenbeeck, Bregje; Cumiskey, Lydia; Verlaan, Martin; Muis, Sanne; Ward, Philip; Kwadijk, Jaap

    2015-04-01

    Most attempts to globally simulate inundation at the land-coast interface rely on maximum flood level GIS-based flood spreading models. These are generally not mass conservative, do not account for the genesis of tidal and surges in time, and do not include channel geometry and surface roughness. Furthermore, these methods cannot be used to study the impact of hazard reducing intervention measures that increase roughness at the land-coast interface. These measures include breakwaters and coastal ecosystems, such as mangrove forests and shell fish and coral reefs. Recently, new datasets and models are becoming available that allow us to greatly improve simulation of inundation in global deltas in a rapid and computationally feasible way. In this poster we demonstrate the feasibility of modelling all global deltas with strongly urbanised areas explicitly using these datasets and models. This will allow initiatives such as the 100 resilient cities (Rockefeller foundation) and the 'making cities resilient' campaign (UNISDR) to tackle the issue of coastal flood risk efficiently. We propose to use the following materials: A subgrid enabling 1D-2D model code Outputs from a global tidal and storm surge model Open topographical data We demonstrate the feasibility of this approach by modelling the Mississippi delta with: a) a lidar derived topography dataset (www.gis.ms.gov/); and b) the recently released 30 meter elevation dataset from the Shuttle Radar Topography Mission. We use the new 3Di subgrid code to rapidly schematise the vast delta area with a quadtree mesh. We force the model at the boundaries with water level estimates during the Katrina cyclone. We invite scientists working on global scale inundation modelling to visit our poster in order to discuss possibilities and limitations of the proposed methods related to model codes, data quality and calibration.

  1. Dynamics of pickup ion velocity distribution function in Titan's plasma environment (TA encounter): 3D hybrid kinetic modeling and comparison with CAPS observations

    NASA Astrophysics Data System (ADS)

    Simpson, D. G.; Lipatov, A. S.; Sittler, E. C.; Hartle, R. E.; Cooper, J. F.

    2013-12-01

    Wave-particle interactions play a very important role in the plasma dynamics near Titan: mass loading, excitation of the low-frequency waves and the formation of the particle velocity distribution function, e.g. ring/shell-like distributions, etc. The kinetic approach is important for estimation of the collision processes e.g. a charge exchange. The particle velocity distribution function also plays a key role for understanding the observed particle fluxes. In this report we discuss the ion velocity distribution function dynamics from 3D hybrid modeling. The modeling is based on recent analysis of the Cassini Plasma Spectrometer (CAPS) ion measurements during the TA flyby. In our model the background ions, all pickup ions, and ionospheric ions are considered as particles, whereas the electrons are described as a fluid. Inhomogeneous photoionization, electron-impact ionization and charge exchange are included in our model. The temperatures of the background electrons and pickup electrons were also included into the generalized Ohm's law. We also take into account the collisions between the ions and neutrals. We use Chamberlain profiles for the exosphere's components and include a simple ionosphere model with M=28 ions that were generated inside the ionosphere. The moon is considered as a weakly conducting body. Our modeling shows that interaction between background plasma and pickup ions H+, H2+, CH4+ and N2+ has a more complicated structure than was observed in the T9 flyby and modeling due to the large gyroradius of the background O+ ions [1,2,3,4]. Special attention will be paid to comparing the simulated pickup ion velocity distribution with CAPS TA observations. We also compare our kinetic modeling with other hybrid and MHD modeling of Titan's environment. References [1] Sittler, E.C., et al., Energy Deposition Processes in Titan's Upper Atmosphere and Its Induced Magnetosphere. In: Titan from Cassini-Huygens, Brown, R.H., Lebreton J.P., Waite, J.H., Eds

  2. The GPlates Portal: Cloud-Based Interactive 3D Visualization of Global Geophysical and Geological Data in a Web Browser.

    PubMed

    Müller, R Dietmar; Qin, Xiaodong; Sandwell, David T; Dutkiewicz, Adriana; Williams, Simon E; Flament, Nicolas; Maus, Stefan; Seton, Maria

    2016-01-01

    The pace of scientific discovery is being transformed by the availability of 'big data' and open access, open source software tools. These innovations open up new avenues for how scientists communicate and share data and ideas with each other and with the general public. Here, we describe our efforts to bring to life our studies of the Earth system, both at present day and through deep geological time. The GPlates Portal (portal.gplates.org) is a gateway to a series of virtual globes based on the Cesium Javascript library. The portal allows fast interactive visualization of global geophysical and geological data sets, draped over digital terrain models. The globes use WebGL for hardware-accelerated graphics and are cross-platform and cross-browser compatible with complete camera control. The globes include a visualization of a high-resolution global digital elevation model and the vertical gradient of the global gravity field, highlighting small-scale seafloor fabric such as abyssal hills, fracture zones and seamounts in unprecedented detail. The portal also features globes portraying seafloor geology and a global data set of marine magnetic anomaly identifications. The portal is specifically designed to visualize models of the Earth through geological time. These space-time globes include tectonic reconstructions of the Earth's gravity and magnetic fields, and several models of long-wavelength surface dynamic topography through time, including the interactive plotting of vertical motion histories at selected locations. The globes put the on-the-fly visualization of massive data sets at the fingertips of end-users to stimulate teaching and learning and novel avenues of inquiry.

  3. The GPlates Portal: Cloud-Based Interactive 3D Visualization of Global Geophysical and Geological Data in a Web Browser

    PubMed Central

    Müller, R. Dietmar; Qin, Xiaodong; Sandwell, David T.; Dutkiewicz, Adriana; Williams, Simon E.; Flament, Nicolas; Maus, Stefan; Seton, Maria

    2016-01-01

    The pace of scientific discovery is being transformed by the availability of ‘big data’ and open access, open source software tools. These innovations open up new avenues for how scientists communicate and share data and ideas with each other and with the general public. Here, we describe our efforts to bring to life our studies of the Earth system, both at present day and through deep geological time. The GPlates Portal (portal.gplates.org) is a gateway to a series of virtual globes based on the Cesium Javascript library. The portal allows fast interactive visualization of global geophysical and geological data sets, draped over digital terrain models. The globes use WebGL for hardware-accelerated graphics and are cross-platform and cross-browser compatible with complete camera control. The globes include a visualization of a high-resolution global digital elevation model and the vertical gradient of the global gravity field, highlighting small-scale seafloor fabric such as abyssal hills, fracture zones and seamounts in unprecedented detail. The portal also features globes portraying seafloor geology and a global data set of marine magnetic anomaly identifications. The portal is specifically designed to visualize models of the Earth through geological time. These space-time globes include tectonic reconstructions of the Earth’s gravity and magnetic fields, and several models of long-wavelength surface dynamic topography through time, including the interactive plotting of vertical motion histories at selected locations. The globes put the on-the-fly visualization of massive data sets at the fingertips of end-users to stimulate teaching and learning and novel avenues of inquiry. PMID:26960151

  4. Self-consistent Synthetic Mantle Discontinuities From Joint Modeling of Geodynamics and Mineral Physics and Their Effects on the 3D Global Wave Field

    NASA Astrophysics Data System (ADS)

    Schuberth, B.; Piazzoni, A.; Bunge, H.; Igel, H.; Steinle-Neumann, G.; Moder, C.; Oeser, J.

    2007-12-01

    Our current understanding of mantle structure and dynamics is to a large part based on inversion of seismic data resulting in tomographic images and on direct analysis of a wide range of seismic phases such as Pdiff, PcP, ScS SdS etc. For solving inverse problems, forward modeling is needed to obtain a synthetic dataset for a given set of model parameters. In this respect, great progress has been made over the last years in the developement of sophisticated numerical full waveform modeling tools. However, the main limitation in the application of this new class of techniques for the forward problem of seismology is the lack of accurate predictions of mantle heterogeneity that allow us to test hypotheses about Earth's mantle. Such predictive models should be based on geodynamic and mineralogical considerations and derived independently of seismological observations. Here, we demonstrate the feasibility of joining forward simulations from geodynamics, mineral physics and seismology to obtain earth-like seismograms. 3D global wave propagation is simulated for dynamically consistent thermal structures derived from 3D mantle circulation modeling (e.g. Bunge et al. 2002), for which the temperatures are converted to seismic velocities using a recently published, thermodynamically self-consistent mineral physics approach (Piazzoni et al. 2007). Assuming a certain, fixed mantle composition (e.g. pyrolite) our mineralogic modeling algorithm computes the stable phases at mantle pressures for a wide range of temperatures by system Gibbs free energy minimization. Through the same equations of state that model the Gibbs free energy, we compute elastic moduli and density for each stable phase assemblage at the same P-T conditions. One straightforward application of this approach is the study of the seismic signature of synthetic mantle discontinuities arising in such models, as the temperature dependent phase transformations occuring at around 410 Km and 660 Km depth are

  5. Normal-mode function representation of global 3-D data sets: open-access software for the atmospheric research community

    NASA Astrophysics Data System (ADS)

    Žagar, N.; Kasahara, A.; Terasaki, K.; Tribbia, J.; Tanaka, H.

    2015-04-01

    This article presents new software for the analysis of global dynamical fields in (re)analyses, weather forecasts and climate models. A new diagnostic tool, developed within the MODES project, allows one to diagnose properties of balanced and inertio-gravity (IG) circulations across many scales. In particular, the IG spectrum, which has only recently become observable, can be studied simultaneously in the mass and wind fields while considering the whole model depth in contrast to the majority of studies. The paper includes the theory of normal-mode function (NMF) expansion, technical details of the Fortran 90 code, examples of namelists which control the software execution and outputs of the software application on the ERA Interim reanalysis data set. The applied libraries and default compiler are from the open-source domain. A limited understanding of Fortran suffices for the successful implementation of the software. The presented application of the software to the ERA Interim data set reveals several aspects of the large-scale circulation after it has been partitioned into the linearly balanced and IG components. The global energy distribution is dominated by the balanced energy while the IG modes contribute around 10% of the total wave energy. However, on sub-synoptic scales, IG energy dominates and it is associated with the main features of tropical variability on all scales. The presented energy distribution and features of the zonally averaged and equatorial circulation provide a reference for the validation of climate models.

  6. Integrating chemistry into 3D climate models: Detailed kinetics in the troposphere and stratosphere of a global climate model

    SciTech Connect

    Kao, C.Y.J.; Elliott, S.; Turco, R.P.; Zhao, X.

    1997-11-01

    This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at Los Alamos National Laboratory (LANL). The motivation for the project is to create the first complete, three-dimensional climate model that enfolds atmospheric photochemistry. The LANL chemical global climate model (GCM) not only distributes the trace greenhouse gases and modifies their concentrations within the detailed photochemical web, but also permits them to influence the radiation field and so force their own transport. Both atmospheric chemistry and fluid dynamics are nonlinear and zonally asymmetric phenomena. They can only be adequately modeled in three dimensions on the global grid. The kinetics-augmented GCM is the only program within the atmospheric community capable of investigating interaction involving chemistry and transport. The authors have conducted case studies of timely three-dimensional chemistry issues. Examples include ozone production from biomass burning plumes, kinetic feedbacks in zonally asymmetric transport phenomena with month- to year-long time scales, and volcano sulfate aerosols with respect to their potential effects on tropospheric ozone depletion.

  7. Realistic primary and new productions in a 3D global biogeochemical model: biological complexity or physical forcing?

    NASA Astrophysics Data System (ADS)

    Popova, E. E.; Coward, A. C.

    2003-04-01

    A nitrogen-based, five compartment biological model has been coupled to a one degree OCCAM (Ocean Circulation and Climate Advanced Modelling Project) model with a KPP ("K profile parameterisation") of the vertical mixing. The biological model state variables are Phytoplankton, Zooplankton, Detritus, Nitrate, and Ammonium. A comparison of the solution with global satellite ocean colour shows that the model is capable of a realistic description of the main seasonal and regional patterns of the surface chlorophyll. Agreement is also good for satellite derived estimates of primary production. In situ data available from local study sites (such as BATS, NABE, India, Papa) are used for the detailed comparison of the model output with the observed ecosystem dynamics in different biological provinces. We discuss performance of the physical and biological model in contrasting areas of the World Ocean. In spite of the biological model being a very simple one, we are able to reproduce the major differences between ecosystem dynamics of these areas. We believe that the success of any global biogeochemical model is dependent first of all on the correct representation of the upper mixed layer (UML) dynamics. Without being able to reproduce contrasting UML regimes in different areas of the World Ocean (such as difference between the North Atlantic and Southern Ocean, or North Atlantic and North Pacific), increased complexity biological models are in danger of producing the right results by the wrong reason.

  8. LLNL-Earth3D

    SciTech Connect

    2013-10-01

    Earth3D is a computer code designed to allow fast calculation of seismic rays and travel times through a 3D 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.

  9. New Models of Hybrid Leadership in Global Higher Education

    ERIC Educational Resources Information Center

    Tonini, Donna C.; Burbules, Nicholas C.; Gunsalus, C. K.

    2016-01-01

    This manuscript highlights the development of a leadership preparation program known as the Nanyang Technological University Leadership Academy (NTULA), exploring the leadership challenges unique to a university undergoing rapid growth in a highly multicultural context, and the hybrid model of leadership it developed in response to globalization.…

  10. Evaluating the Credibility of Transport Processes in the Global Modeling Initiative 3D Model Simulations of Ozone Recovery

    NASA Technical Reports Server (NTRS)

    Strahan, Susan E.; Douglass, Anne R.

    2003-01-01

    The Global Modeling Initiative has integrated two 35-year simulations of an ozone recovery scenario with an offline chemistry and transport model using two different meteorological inputs. Physically based diagnostics, derived from satellite and aircraft data sets, are described and then used to evaluate the realism of temperature and transport processes in the simulations. Processes evaluated include barrier formation in the subtropics and polar regions, and extratropical wave-driven transport. Some diagnostics are especially relevant to simulation of lower stratospheric ozone, but most are applicable to any stratospheric simulation. The temperature evaluation, which is relevant to gas phase chemical reactions, showed that both sets of meteorological fields have near climatological values at all latitudes and seasons at 30 hPa and below. Both simulations showed weakness in upper stratospheric wave driving. The simulation using input from a general circulation model (GMI(sub GCM)) showed a very good residual circulation in the tropics and northern hemisphere. The simulation with input from a data assimilation system (GMI(sub DAS)) performed better in the midlatitudes than at high latitudes. Neither simulation forms a realistic barrier at the vortex edge, leading to uncertainty in the fate of ozone-depleted vortex air. Overall, tracer transport in the offline GMI(sub GCM) has greater fidelity throughout the stratosphere than the GMI(sub DAS).

  11. A global 3-D model to simulate long-range transport of PAHs: Effect of climate on transport to the Arctic

    NASA Astrophysics Data System (ADS)

    Friedman, C. L.; Selin, N. E.

    2011-12-01

    We simulate the long-range transport of polycyclic aromatic hydrocarbons (PAHs) to the Arctic under present and future climate using a global 3-D chemical transport model (GEOS-Chem). PAHs, toxic byproducts of combustion, reach the Arctic by long-range atmospheric transport. PAHs are semivolatile compounds that partition between the gas and particle phases. We implement temperature-dependent PAH partitioning into hydrophobic organic carbon (OC) and black carbon (BC) aerosols in the model to simulate this behavior. First, we test the validity of the model by comparing results to global measurements of the PAHs phenanthrene (PHE), pyrene (PYR), and benzo[a]pyrene (BaP) and find that for mean global and mean Arctic concentrations, measurements and model results are not statistically different and that the model captures 64 - 74% (r2s) of the concentration variability in non-urban locations. We then simulate daily transport of PHE, PYR, and BaP to the Arctic for the years 2005-2009. Preliminary results suggest the model captures up to 50% (r2s) of the variability in Arctic concentrations, and is able to capture episodic events. Source-receptor analyses indicate European and Russian sources account for approximately 80% of PAHs in the Arctic. The sensitivity of PAH transport to simulated future climate meteorology (GCAP) and to variable OC and BC concentrations is investigated, particularly with respect to transport to the Arctic and remote exposures. The implications for regional and global PAH regulatory policies are discussed.

  12. Study of morphology effects on magnetic interactions and band gap variations for 3d late transition metal bi-doped ZnO nanostructures by hybrid DFT calculations

    SciTech Connect

    Datta, Soumendu Baral, Sayan; Mookerjee, Abhijit; Kaphle, Gopi Chandra

    2015-08-28

    Using density functional theory (DFT) based electronic structure calculations, the effects of morphology of semiconducting nanostructures on the magnetic interaction between two magnetic dopant atoms as well as a possibility of tuning band gaps have been studied in the case of the bi-doped (ZnO){sub 24} nanostructures with the impurity dopant atoms of the 3d late transition metals—Mn, Fe, Co, Ni, and Cu. To explore the morphology effect, three different structures of the host (ZnO){sub 24} nano-system, having different degrees of spatial confinement, have been considered: a two dimensional nanosheet, a one dimensional nanotube, and a finite cage-shaped nanocluster. The present study employs hybrid density functional theory to accurately describe the electronic structure of all the systems. It is shown here that the magnetic coupling between the two dopant atoms remains mostly anti-ferromagnetic in the course of changing the morphology from the sheet geometry to the cage-shaped geometry of the host systems, except for the case of energetically most stable bi-Mn doping, which shows a transition from ferromagnetic to anti-ferromagnetic coupling with decreasing aspect ratio of the host system. The effect of the shape change, however, has a significant effect on the overall band gap variations of both the pristine as well as all the bi-doped systems, irrespective of the nature of the dopant atoms and provides a means for easy tunability of their optoelectronic properties.

  13. 3D assembly based on 2D structure of Cellulose Nanofibril/Graphene Oxide Hybrid Aerogel for Adsorptive Removal of Antibiotics in Water

    PubMed Central

    Yao, Qiufang; Fan, Bitao; Xiong, Ye; Jin, Chunde; Sun, Qingfeng; Sheng, Chengmin

    2017-01-01

    Cellulose nanofibril/graphene oxide hybrid (CNF/GO) aerogel was fabricated via a one-step ultrasonication method for adsorptive removal of 21 kinds of antibiotics in water. The as-prepared CNF/GO aerogel possesses interconnected 3D network microstructure, in which GO nanosheets with 2D structure were intimately grown along CNF through hydrogen bonds. The aerogel exhibited superior adsorption capacity toward the antibiotics. The removal percentages (R%) of the antibiotics were more than 69% and the sequence of six categories antibiotics according to the adsorption efficiency was as follows: Tetracyclines > Quinolones > Sulfonamides > Chloramphenicols > β-Lactams > Macrolides. The adsorption mechanism was proposed to be electrostatic attraction, p-π interaction, π-π interaction and hydrogen bonds. In detail, the adsorption capacities of CNF/GO aerogel were 418.7 mg·g−1 for chloramphenicol, 291.8 mg·g−1 for macrolides, 128.3 mg·g−1 for quinolones, 230.7 mg·g−1 for β-Lactams, 227.3 mg·g−1 for sulfonamides, and 454.6 mg·g−1 for tetracyclines calculated by the Langmuir isotherm models. Furthermore, the regenerated aerogels still could be repeatedly used after ten cycles without obvious degradation of adsorption performance. PMID:28368045

  14. High-performance hybrid supercapacitor with 3D hierarchical porous flower-like layered double hydroxide grown on nickel foam as binder-free electrode

    NASA Astrophysics Data System (ADS)

    Zhang, Luojiang; Hui, Kwun Nam; San Hui, Kwan; Lee, Haiwon

    2016-06-01

    The synthesis of layered double hydroxide (LDH) as electroactive material has been well reported; however, fabricating an LDH electrode with excellent electrochemical performance at high current density remains a challenge. In this paper, we report a 3D hierarchical porous flower-like NiAl-LDH grown on nickel foam (NF) through a liquid-phase deposition method as a high-performance binder-free electrode for energy storage. With large ion-accessible surface area as well as efficient electron and ion transport pathways, the prepared LDH-NF electrode achieves high specific capacity (1250 C g-1 at 2 A g-1 and 401 C g-1 at 50 A g-1) after 5000 cycles of activation at 20 A g-1 and high cycling stability (76.7% retention after another 5000 cycles at 50 A g-1), which is higher than those of most previously reported NiAl-LDH-based materials. Moreover, a hybrid supercapacitor with LDH-NF as the positive electrode and porous graphene nanosheet coated on NF (GNS-NF) as the negative electrode, delivers high energy density (30.2 Wh kg-1 at a power density of 800 W kg-1) and long cycle life, which outperforms the other devices reported in the literature. This study shows that the prepared LDH-NF electrode offers great potential in energy storage device applications.

  15. 3D assembly based on 2D structure of Cellulose Nanofibril/Graphene Oxide Hybrid Aerogel for Adsorptive Removal of Antibiotics in Water.

    PubMed

    Yao, Qiufang; Fan, Bitao; Xiong, Ye; Jin, Chunde; Sun, Qingfeng; Sheng, Chengmin

    2017-04-03

    Cellulose nanofibril/graphene oxide hybrid (CNF/GO) aerogel was fabricated via a one-step ultrasonication method for adsorptive removal of 21 kinds of antibiotics in water. The as-prepared CNF/GO aerogel possesses interconnected 3D network microstructure, in which GO nanosheets with 2D structure were intimately grown along CNF through hydrogen bonds. The aerogel exhibited superior adsorption capacity toward the antibiotics. The removal percentages (R%) of the antibiotics were more than 69% and the sequence of six categories antibiotics according to the adsorption efficiency was as follows: Tetracyclines > Quinolones > Sulfonamides > Chloramphenicols > β-Lactams > Macrolides. The adsorption mechanism was proposed to be electrostatic attraction, p-π interaction, π-π interaction and hydrogen bonds. In detail, the adsorption capacities of CNF/GO aerogel were 418.7 mg·g(-1) for chloramphenicol, 291.8 mg·g(-1) for macrolides, 128.3 mg·g(-1) for quinolones, 230.7 mg·g(-1) for β-Lactams, 227.3 mg·g(-1) for sulfonamides, and 454.6 mg·g(-1) for tetracyclines calculated by the Langmuir isotherm models. Furthermore, the regenerated aerogels still could be repeatedly used after ten cycles without obvious degradation of adsorption performance.

  16. Predicting Seismological and Geochemical Observations Using Global and Regional 3-D Spherical Convection Models Incorporating Self-Consistently Calculated Mineral Physics

    NASA Astrophysics Data System (ADS)

    Tackley, P. J.; Nakagawa, T.; Deschamps, F.; Connolly, J. A.; Duchoiselle, L.

    2007-12-01

    The latest generation of the global 3-D spherical convection model yinyang-Stag3D allows the direct computation of a planet's thermo-chemical evolution, including self-consistently generated plate tectonics, chemical differentiation induced by melting, large viscosity variations, and a realistic treatment of phase diagrams and material properties. The latter has recently been added using free energy minimization to compute stable phases as a function of temperature, pressure, and composition as expressed by ratios of the five main oxides, and thus avoids the need for increasingly complicated and ad hoc parameterizations of phase transitions. Modern supercomputers and clusters also allow increasingly higher resolution, with up to 1.2 billion unknowns possible on only 32 dual-processor nodes of an opteron cluster. In ongoing research, results from such modeling efforts are compared to a wide range of seismological observations, ranging from statistical comparisons with global tomographic inversions (standard and probabilistic), and comparisons with regional models, for example of D" structure and heterogeneity, including structures that are sharp-sided and/or related to the post-perovskite phase transition. Such results also have implications for geochemistry including the possible location of "reservoirs". For high-resolution studies, a region of a sphere, instead of a whole sphere, can be modeled, and in this mode models of slab-CMB interaction are presented that show some of the small-scale thermo-compositional-phase structures that can be generated. Global models also allow the computation of planetary secular cooling, including prediction of how the core heat flux varies with time hence the evolution of the geodynamo, and possible transitions in plate tectonic mode. Thus, a suite of predictions can be made.

  17. Low-cost photodynamic therapy devices for global health settings: Characterization of battery-powered LED performance and smartphone imaging in 3D tumor models

    NASA Astrophysics Data System (ADS)

    Hempstead, Joshua; Jones, Dustin P.; Ziouche, Abdelali; Cramer, Gwendolyn M.; Rizvi, Imran; Arnason, Stephen; Hasan, Tayyaba; Celli, Jonathan P.

    2015-05-01

    A lack of access to effective cancer therapeutics in resource-limited settings is implicated in global cancer health disparities between developed and developing countries. Photodynamic therapy (PDT) is a light-based treatment modality that has exhibited safety and efficacy in the clinic using wavelengths and irradiances achievable with light-emitting diodes (LEDs) operated on battery power. Here we assess low-cost enabling technology to extend the clinical benefit of PDT to regions with little or no access to electricity or medical infrastructure. We demonstrate the efficacy of a device based on a 635 nm high-output LED powered by three AA disposable alkaline batteries, to achieve strong cytotoxic response in monolayer and 3D cultures of A431 squamous carcinoma cells following photosensitization by administering aminolevulinic acid (ALA) to induce the accumulation of protoporphyrin IX (PpIX). Here we characterize challenges of battery-operated device performance, including battery drain and voltage stability specifically over relevant PDT dose parameters. Further motivated by the well-established capacity of PDT photosensitizers to serve as tumour-selective fluorescence contrast agents, we demonstrate the capability of a consumer smartphone with low-cost add-ons to measure concentration-dependent PpIX fluorescence. This study lays the groundwork for the on-going development of image-guided ALA-PDT treatment technologies for global health applications.

  18. Global and regional kinematics of the cervical spine during upper cervical spine manipulation: a reliability analysis of 3D motion data.

    PubMed

    Dugailly, Pierre-Michel; Beyer, Benoît; Sobczak, Stéphane; Salvia, Patrick; Feipel, Véronique

    2014-10-01

    Studies reporting spine kinematics during cervical manipulation are usually related to continuous global head-trunk motion or discrete angular displacements for pre-positioning. To date, segmental data analyzing continuous kinematics of cervical manipulation is lacking. The objective of this study was to investigate upper cervical spine (UCS) manipulation in vitro. This paper reports an inter- and intra-rater reliability analysis of kinematics during high velocity low amplitude manipulation of the UCS. Integration of kinematics into specific-subject 3D models has been processed as well for providing anatomical motion representation during thrust manipulation. Three unembalmed specimens were included in the study. Restricted dissection was realized to attach technical clusters to each bone of interest (skull, C1-C4 and sternum). During manipulation, bone motion data was computed using an optoelectronic system. The reliability of manipulation kinematics was assessed for three experimented practitioners performing two trials of 3 repetitions on two separate days. During UCS manipulation, average global head-trunk motion ROM (±SD) were 14 ± 5°, 35 ± 7° and 14 ± 8° for lateral bending, axial rotation and flexion-extension, respectively. For regional ROM (C0-C2), amplitudes were 10 ± 5°, 30 ± 5° and 16 ± 4° for the same respective motions. Concerning the reliability, mean RMS ranged from 1° to 4° and from 3° to 6° for intra- and inter-rater comparisons, respectively. The present results confirm the limited angular displacement during manipulation either for global head-trunk or for UCS motion components, especially for axial rotation. Additionally, kinematics variability was low confirming intra- and inter-practitioners consistency of UCS manipulation achievement.

  19. SU-E-T-451: Hybrid-VMAT: A Novel Technique Combining VMAT and 3D in Planning Whole Breast Radiotherapy with a Simultaneously-Integrated Boost (WBRT+SIB)

    SciTech Connect

    Guida, K; Qamar, K; Thompson, M

    2015-06-15

    Purpose: The RTOG 1005 trial offered a hypofractionated arm in delivering WBRT+SIB. Traditionally, treatments were planned at our institution using field-in-field (FiF) tangents with a concurrent 3D conformal boost. With the availability of VMAT, it is possible that a hybrid VMAT-3D planning technique could provide another avenue in treating WBRT+SIB. Methods: A retrospective study of nine patients previously treated using RTOG 1005 guidelines was performed to compare FiF+3D plans with the hybrid technique. A combination of static tangents and partial VMAT arcs were used in base-dose optimization. The hybrid plans were optimized to deliver 4005cGy to the breast PTVeval and 4800cGy to the lumpectomy PTVeval over 15 fractions. Plans were optimized to meet the planning goals dictated by RTOG 1005. Results: Hybrid plans yielded similar coverage of breast and lumpectomy PTVs (average D95 of 4013cGy compared to 3990cGy for conventional), while reducing the volume of high dose within the breast; the average D30 and D50 for the hybrid technique were 4517cGy and 4288cGy, compared to 4704cGy and 4377cGy for conventional planning. Hybrid plans increased conformity as well, yielding CI95% values of 1.22 and 1.54 for breast and lumpectomy PTVeval volumes; in contrast, conventional plans averaged 1.49 and 2.27, respectively. The nearby organs at risk (OARs) received more low dose with the hybrid plans due to low dose spray from the partial arcs, but all hybrid plans did meet the acceptable constraints, at a minimum, from the protocol. Treatment planning time was also reduced, as plans were inversely optimized (VMAT) rather than forward optimized. Conclusion: Hybrid-VMAT could be a solution in delivering WB+SIB, as plans yield very conformal treatment plans and maintain clinical standards in OAR sparing. For treating breast cancer patients with a simultaneously-integrated boost, Hybrid-VMAT offers superiority in dosimetric conformity and planning time as compared to FIF

  20. Europeana and 3D

    NASA Astrophysics Data System (ADS)

    Pletinckx, D.

    2011-09-01

    The current 3D hype creates a lot of interest in 3D. People go to 3D movies, but are we ready to use 3D in our homes, in our offices, in our communication? Are we ready to deliver real 3D to a general public and use interactive 3D in a meaningful way to enjoy, learn, communicate? The CARARE project is realising this for the moment in the domain of monuments and archaeology, so that real 3D of archaeological sites and European monuments will be available to the general public by 2012. There are several aspects to this endeavour. First of all is the technical aspect of flawlessly delivering 3D content over all platforms and operating systems, without installing software. We have currently a working solution in PDF, but HTML5 will probably be the future. Secondly, there is still little knowledge on how to create 3D learning objects, 3D tourist information or 3D scholarly communication. We are still in a prototype phase when it comes to integrate 3D objects in physical or virtual museums. Nevertheless, Europeana has a tremendous potential as a multi-facetted virtual museum. Finally, 3D has a large potential to act as a hub of information, linking to related 2D imagery, texts, video, sound. We describe how to create such rich, explorable 3D objects that can be used intuitively by the generic Europeana user and what metadata is needed to support the semantic linking.

  1. Hybrid local FEM/global LISA modeling of guided wave propagation and interaction with damage in composite structures

    NASA Astrophysics Data System (ADS)

    Shen, Yanfeng; Cesnik, Carlos E. S.

    2015-03-01

    This paper presents a hybrid modeling technique for the efficient simulation of guided wave propagation and interaction with damage in composite structures. This hybrid approach uses a local finite element model (FEM) to compute the excitability of guided waves generated by piezoelectric transducers, while the global domain wave propagation, wave-damage interaction, and boundary reflections are modeled with the local interaction simulation approach (LISA). A small-size multi-physics FEM with non-reflective boundaries (NRB) was built to obtain the excitability information of guided waves generated by the transmitter. Frequency-domain harmonic analysis was carried out to obtain the solution for all the frequencies of interest. Fourier and inverse Fourier transform and frequency domain convolution techniques are used to obtain the time domain 3-D displacement field underneath the transmitter under an arbitrary excitation. This 3-D displacement field is then fed into the highly efficient time domain LISA simulation module to compute guided wave propagation, interaction with damage, and reflections at structural boundaries. The damping effect of composite materials was considered in the modified LISA formulation. The grids for complex structures were generated using commercial FEM preprocessors and converted to LISA connectivity format. Parallelization of the global LISA solution was achieved through Compute Unified Design Architecture (CUDA) running on Graphical Processing Unit (GPU). The multi-physics local FEM can reliably capture the detailed dimensions and local dynamics of the piezoelectric transducers. The global domain LISA can accurately solve the 3-D elastodynamic wave equations in a highly efficient manner. By combining the local FEM with global LISA, the efficient and accurate simulation of guided wave structural health monitoring procedure is achieved. Two numerical case studies are presented: (1) wave propagation in a unidirectional CFRP composite plate

  2. 3D Global PIC simulation of Alfvenic transition layers at the cusp outer boundary during IMF rotations from north to south

    NASA Astrophysics Data System (ADS)

    Cai, D. S.; Lembege, B.; Esmaeili, A.; Nishikawa, K.

    2013-12-01

    Statistical experimental observations of the cusp boundaries from CLUSTER mission made by Lavraud et al. (2005) have clearly evidenced the presence of a transition layer inside the magnetosheath near the outer boundary of the cusp. This layer characterized by Log(MA)~ 1 allows a transition from super-Alfvenic to sub-Alfvenic bulk flow from the exterior to the interior side of the outer cusp and has been mainly observed experimentally under northward interplanetary magnetic field (IMF). The role of this layer is important in order to understand the flow variations (and later the entry and precipitation of particles) when penetrating the outer boundary of the cusp. In order to analyze this layer, a large 3D PIC simulation of the global solar wind-terrestrial magnetosphere interaction have been performed, and the attention has been focused on the cusp region and its nearby surrounding during IMF rotation from north to south. Present results retrieve quite well the presence of this layer within the meridian plane for exactly northward IMF, but its location differs in the sense that it is located slightly below the X reconnection region associated to the nearby magnetopause (above the outer boundary of the cusp). In order to clarify this question, an extensive study has been performed as follows: (i) a 3D mapping of this transition layer in order to analyze more precisely the thickness, the location and the spatial extension of this layer on the magnetosphere flanks for a fixed Northward IMF configuration; (ii) a parametric study in order to analyze the impact of the IMF rotation from north to south on the persistence and the main features of this transition layer. The locations of this transition layer slightly radially expand and shrink during the IMF rotation and the thickness of the layer increases during the rotation. We show how these transition layers render the flow from super to sub Alfvenic and allow the particles enter into the magnetic cusp region. Alfven

  3. A Novel Hybrid Firefly Algorithm for Global Optimization

    PubMed Central

    Zhang, Lina; Liu, Liqiang; Yang, Xin-She; Dai, Yuntao

    2016-01-01

    Global optimization is challenging to solve due to its nonlinearity and multimodality. Traditional algorithms such as the gradient-based methods often struggle to deal with such problems and one of the current trends is to use metaheuristic algorithms. In this paper, a novel hybrid population-based global optimization algorithm, called hybrid firefly algorithm (HFA), is proposed by combining the advantages of both the firefly algorithm (FA) and differential evolution (DE). FA and DE are executed in parallel to promote information sharing among the population and thus enhance searching efficiency. In order to evaluate the performance and efficiency of the proposed algorithm, a diverse set of selected benchmark functions are employed and these functions fall into two groups: unimodal and multimodal. The experimental results show better performance of the proposed algorithm compared to the original version of the firefly algorithm (FA), differential evolution (DE) and particle swarm optimization (PSO) in the sense of avoiding local minima and increasing the convergence rate. PMID:27685869

  4. Self consistent particles dynamics in/out of the cusp region by using back tracking technics; a global 3D PIC simulation approach

    NASA Astrophysics Data System (ADS)

    Esmaeili, A.; Cai, D.; Lembege, B.; Nishikawa, K.

    2013-12-01

    Large scale three dimensionbal PIC (particle in cell) simulations are presently used in order to analyze the global solar wind-terrestrial magnetosphere intreraction within a full self-consistent approach, and where both electrons and ions are treated as an assembly of individual particles. This 3D kinetic approach allows us to analyze in particular the dynamics and the fine structures of the cusp region when including self consistently not only its whole neighborhood (in the terrestrial magnetosphere) but also the impact of the solar wind and the interplanetary field (IMF) features. Herein, we focuss our attention on the cusp region and in particular on the acceleration and precipitation of particles (both ions and electrons) within the cusp. In present simulations, the IMF is chosen northward, (i.e. where the X -reconnection region is just above the cusp, in the meridian plane). Back-trackings of self-consistent particles are analyzed in details in order to determine (i) which particles (just above the cusp) are precipitated deeply into the cusp, (ii) which populations are injected from the cusp into the nearby tail, (iii) where the particles suffer the largest energisation along their self-consistent trajectories, (iv) where these populations accumulate, and (v) where the most energetic particles are originally coming from. This approach allows to make a traking of particles within the scenario "solar wind-magnetosheath- cusp -nearbytail"; moreover it strongly differs from the standard test particles technics and allows to provide informations not accessible when using full MHD approach. Keywords: Tracing Particles, Particle In Cell (PIC) simulation, double cusp, test particles method, IMF, Solar wind, Magnetosphere

  5. 3d-3d correspondence revisited

    DOE PAGES

    Chung, Hee -Joong; Dimofte, Tudor; Gukov, Sergei; ...

    2016-04-21

    In fivebrane compactifications on 3-manifolds, we point out the importance of all flat connections in the proper definition of the effective 3d N = 2 theory. The Lagrangians of some theories with the desired properties can be constructed with the help of homological knot invariants that categorify colored Jones polynomials. Higgsing the full 3d theories constructed this way recovers theories found previously by Dimofte-Gaiotto-Gukov. As a result, we also consider the cutting and gluing of 3-manifolds along smooth boundaries and the role played by all flat connections in this operation.

  6. Creating and Using Interactive, 3D-Printed Models to Improve Student Comprehension of the Bohr Model of the Atom, Bond Polarity, and Hybridization

    ERIC Educational Resources Information Center

    Smiar, Karen; Mendez, J. D.

    2016-01-01

    Molecular model kits have been used in chemistry classrooms for decades but have seen very little recent innovation. Using 3D printing, three sets of physical models were created for a first semester, introductory chemistry course. Students manipulated these interactive models during class activities as a supplement to existing teaching tools for…

  7. An effective hyper-resolution pseudo-3D implementation of small scale hydrological features to improve regional and global climate studies

    NASA Astrophysics Data System (ADS)

    Hazenberg, P.; Broxton, P. D.; Gochis, D. J.; Niu, G.; Pelletier, J. D.; Troch, P. A.; Zeng, X.

    2013-12-01

    Global land surface processes play an important role in the land-atmosphere exchanges of energy, water, and trace gases. As such, correct representation of the different hydrological processes has long been an important research topic in climate modeling. Historically, these processes were presented at a relatively coarse horizontal resolution, focusing mainly on the vertical hydrological response, while lateral exchanges were either disregarded or implemented in a relatively crude manner. Increases in computational power have led to higher resolution regional and global land surface models. For the coming years, it is anticipated that these models will simulate the hydrological response of the earth surface at a 100-1000 meter pixel size, which is stated as hyper-resolution earth surface modeling. At these relatively high resolutions, correct representation of groundwater, including lateral interactions across pixels and with the channel network, becomes important. Next to that, at these high resolutions elevation differences have a larger impact on the hydrological response and therefore need to be represented properly. We will present a new hydrological framework specifically developed to operate at these hyper-resolutions. Our new approach discriminates between differences in the hydrological response of hillslopes, riparian zones, wetlands and flat regions within a given pixel, while interacting with the channel network and the atmosphere. Instead of applying the traditional conceptual approach, these interactions are incorporated using a physically-based approach. In order to be able to differentiate between these different hydrological features, globally available high-resolution 30 meter DEM data were analyzed using a state-of-the-art digital geomorphological identification method. Based on these techniques, local estimates of soil depth, hillslope width functions, channel network density, etc. were also obtained that are used as input to the model In the

  8. 3D and Education

    NASA Astrophysics Data System (ADS)

    Meulien Ohlmann, Odile

    2013-02-01

    Today the industry offers a chain of 3D products. Learning to "read" and to "create in 3D" becomes an issue of education of primary importance. 25 years professional experience in France, the United States and Germany, Odile Meulien set up a personal method of initiation to 3D creation that entails the spatial/temporal experience of the holographic visual. She will present some different tools and techniques used for this learning, their advantages and disadvantages, programs and issues of educational policies, constraints and expectations related to the development of new techniques for 3D imaging. Although the creation of display holograms is very much reduced compared to the creation of the 90ies, the holographic concept is spreading in all scientific, social, and artistic activities of our present time. She will also raise many questions: What means 3D? Is it communication? Is it perception? How the seeing and none seeing is interferes? What else has to be taken in consideration to communicate in 3D? How to handle the non visible relations of moving objects with subjects? Does this transform our model of exchange with others? What kind of interaction this has with our everyday life? Then come more practical questions: How to learn creating 3D visualization, to learn 3D grammar, 3D language, 3D thinking? What for? At what level? In which matter? for whom?

  9. Global warming induced hybrid rainy seasons in the Sahel

    NASA Astrophysics Data System (ADS)

    Salack, Seyni; Klein, Cornelia; Giannini, Alessandra; Sarr, Benoit; Worou, Omonlola N.; Belko, Nouhoun; Bliefernicht, Jan; Kunstman, Harald

    2016-10-01

    The small rainfall recovery observed over the Sahel, concomitant with a regional climate warming, conceals some drought features that exacerbate food security. The new rainfall features include false start and early cessation of rainy seasons, increased frequency of intense daily rainfall, increasing number of hot nights and warm days and a decreasing trend in diurnal temperature range. Here, we explain these mixed dry/wet seasonal rainfall features which are called hybrid rainy seasons by delving into observed data consensus on the reduction in rainfall amount, its spatial coverage, timing and erratic distribution of events, and other atmospheric variables crucial in agro-climatic monitoring and seasonal forecasting. Further composite investigations of seasonal droughts, oceans warming and the regional atmospheric circulation nexus reveal that the low-to-mid-level atmospheric winds pattern, often stationary relative to either strong or neutral El-Niño-Southern-Oscillations drought patterns, associates to basin warmings in the North Atlantic and the Mediterranean Sea to trigger hybrid rainy seasons in the Sahel. More challenging to rain-fed farming systems, our results suggest that these new rainfall conditions will most likely be sustained by global warming, reshaping thereby our understanding of food insecurity in this region.

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

    NASA Technical Reports Server (NTRS)

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

    1973-01-01

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

  11. Design of the 1.5 MW, 30-96 MHz ultra-wideband 3 dB high power hybrid coupler for Ion Cyclotron Resonance Frequency (ICRF) heating in fusion grade reactor

    SciTech Connect

    Yadav, Rana Pratap Kumar, Sunil; Kulkarni, S. V.

    2016-01-15

    Design and developmental procedure of strip-line based 1.5 MW, 30-96 MHz, ultra-wideband high power 3 dB hybrid coupler has been presented and its applicability in ion cyclotron resonance heating (ICRH) in tokamak is discussed. For the high power handling capability, spacing between conductors and ground need to very high. Hence other structural parameters like strip-width, strip thickness coupling gap, and junction also become large which can be gone upto optimum limit where various constrains like fabrication tolerance, discontinuities, and excitation of higher TE and TM modes become prominent and significantly deteriorates the desired parameters of the coupled lines system. In designed hybrid coupler, two 8.34 dB coupled lines are connected in tandem to get desired coupling of 3 dB and air is used as dielectric. The spacing between ground and conductors are taken as 0.164 m for 1.5 MW power handling capability. To have the desired spacing, each of 8.34 dB segments are designed with inner dimension of 3.6 × 1.0 × 40 cm where constraints have been significantly realized, compensated, and applied in designing of 1.5 MW hybrid coupler and presented in paper.

  12. Strong light scattering and broadband (UV to IR) photoabsorption in stretchable 3D hybrid architectures based on Aerographite decorated by ZnO nanocrystallites

    PubMed Central

    Tiginyanu, Ion; Ghimpu, Lidia; Gröttrup, Jorit; Postolache, Vitalie; Mecklenburg, Matthias; Stevens-Kalceff, Marion A.; Ursaki, Veaceslav; Payami, Nader; Feidenhansl, Robert; Schulte, Karl; Adelung, Rainer; Mishra, Yogendra Kumar

    2016-01-01

    In present work, the nano- and microscale tetrapods from zinc oxide were integrated on the surface of Aerographite material (as backbone) in carbon-metal oxide hybrid hierarchical network via a simple and single step magnetron sputtering process. The fabricated hybrid networks are characterized for morphology, microstructural and optical properties. The cathodoluminescence investigations revealed interesting luminescence features related to carbon impurities and inherent host defects in zinc oxide. Because of the wide bandgap of zinc oxide and its intrinsic defects, the hybrid network absorbs light in the UV and visible regions, however, this broadband photoabsorption behavior extends to the infrared (IR) region due to the dependence of the optical properties of ZnO architectures upon size and shape of constituent nanostructures and their doping by carbon impurities. Such a phenomenon of broadband photoabsorption ranging from UV to IR for zinc oxide based hybrid materials is novel. Additionally, the fabricated network exhibits strong visible light scattering behavior. The developed Aerographite/nanocrystalline ZnO hybrid network materials, equipped with broadband photoabsorption and strong light scattering, are very promising candidates for optoelectronic technologies. PMID:27616632

  13. Strong light scattering and broadband (UV to IR) photoabsorption in stretchable 3D hybrid architectures based on Aerographite decorated by ZnO nanocrystallites

    NASA Astrophysics Data System (ADS)

    Tiginyanu, Ion; Ghimpu, Lidia; Gröttrup, Jorit; Postolache, Vitalie; Mecklenburg, Matthias; Stevens-Kalceff, Marion A.; Ursaki, Veaceslav; Payami, Nader; Feidenhansl, Robert; Schulte, Karl; Adelung, Rainer; Mishra, Yogendra Kumar

    2016-09-01

    In present work, the nano- and microscale tetrapods from zinc oxide were integrated on the surface of Aerographite material (as backbone) in carbon-metal oxide hybrid hierarchical network via a simple and single step magnetron sputtering process. The fabricated hybrid networks are characterized for morphology, microstructural and optical properties. The cathodoluminescence investigations revealed interesting luminescence features related to carbon impurities and inherent host defects in zinc oxide. Because of the wide bandgap of zinc oxide and its intrinsic defects, the hybrid network absorbs light in the UV and visible regions, however, this broadband photoabsorption behavior extends to the infrared (IR) region due to the dependence of the optical properties of ZnO architectures upon size and shape of constituent nanostructures and their doping by carbon impurities. Such a phenomenon of broadband photoabsorption ranging from UV to IR for zinc oxide based hybrid materials is novel. Additionally, the fabricated network exhibits strong visible light scattering behavior. The developed Aerographite/nanocrystalline ZnO hybrid network materials, equipped with broadband photoabsorption and strong light scattering, are very promising candidates for optoelectronic technologies.

  14. Strong light scattering and broadband (UV to IR) photoabsorption in stretchable 3D hybrid architectures based on Aerographite decorated by ZnO nanocrystallites.

    PubMed

    Tiginyanu, Ion; Ghimpu, Lidia; Gröttrup, Jorit; Postolache, Vitalie; Mecklenburg, Matthias; Stevens-Kalceff, Marion A; Ursaki, Veaceslav; Payami, Nader; Feidenhansl, Robert; Schulte, Karl; Adelung, Rainer; Mishra, Yogendra Kumar

    2016-09-12

    In present work, the nano- and microscale tetrapods from zinc oxide were integrated on the surface of Aerographite material (as backbone) in carbon-metal oxide hybrid hierarchical network via a simple and single step magnetron sputtering process. The fabricated hybrid networks are characterized for morphology, microstructural and optical properties. The cathodoluminescence investigations revealed interesting luminescence features related to carbon impurities and inherent host defects in zinc oxide. Because of the wide bandgap of zinc oxide and its intrinsic defects, the hybrid network absorbs light in the UV and visible regions, however, this broadband photoabsorption behavior extends to the infrared (IR) region due to the dependence of the optical properties of ZnO architectures upon size and shape of constituent nanostructures and their doping by carbon impurities. Such a phenomenon of broadband photoabsorption ranging from UV to IR for zinc oxide based hybrid materials is novel. Additionally, the fabricated network exhibits strong visible light scattering behavior. The developed Aerographite/nanocrystalline ZnO hybrid network materials, equipped with broadband photoabsorption and strong light scattering, are very promising candidates for optoelectronic technologies.

  15. Comparing parametric solid modelling/reconfiguration, global shape modelling and free-form deformation for the generation of 3D digital models of femurs from X-ray images.

    PubMed

    Filippi, Stefano; Motyl, Barbara; Bandera, Camillo

    2009-02-01

    At present, computer assisted surgery systems help orthopaedic surgeons both plan and perform surgical procedures. To enable these systems to function, it is crucial to have at one's disposal 3D models of anatomical structures, surgical tools and prostheses (if required). This paper analyses and compares three methods for generating 3D digital models of anatomical structures starting from X-ray images: parametric solid modelling/reconfiguration, global shape modelling and free-form deformation. Seven experiences involving the generation of a femur model were conducted by software developers and different skilled users. These experiences are described in detail and compared at different stages and from different points of view.

  16. 3D Imaging.

    ERIC Educational Resources Information Center

    Hastings, S. K.

    2002-01-01

    Discusses 3 D imaging as it relates to digital representations in virtual library collections. Highlights include X-ray computed tomography (X-ray CT); the National Science Foundation (NSF) Digital Library Initiatives; output peripherals; image retrieval systems, including metadata; and applications of 3 D imaging for libraries and museums. (LRW)

  17. Converting 2D inorganic-organic ZnSe-DETA hybrid nanosheets into 3D hierarchical nanosheet-based ZnSe microspheres with enhanced visible-light-driven photocatalytic performances

    NASA Astrophysics Data System (ADS)

    Wu, Xuan; Xu, Rui; Zhu, Rongjiao; Wu, Rui; Zhang, Bin

    2015-05-01

    Engineering two-dimensional (2D) nanosheets into three-dimensional (3D) hierarchical structures is one of the great challenges in nanochemistry and materials science. We report a facile and simple chemical conversion route to fabricate 3D hierarchical nanosheet-based ZnSe microspheres by using 2D inorganic-organic hybrid ZnSe-DETA (DETA = diethylenetriamine) nanosheets as the starting precursors. The conversion mechanism involves the controlled depletion of the organic-component (DETA) from the hybrid precursors and the subsequent self-assembly of the remnant inorganic-component (ZnSe). The transformation reaction of ZnSe-DETA nanosheets is mainly influenced by the concentration of DETA in the reaction solution. We demonstrated that this organic-component depletion method could be extended to the synthesis of other hierarchical structures of metal sulfides. In addition, the obtained hierarchical nanosheet-based ZnSe microspheres exhibited outstanding performance in visible light photocatalytic degradation of methyl orange and were highly active for photocatalytic H2 production.Engineering two-dimensional (2D) nanosheets into three-dimensional (3D) hierarchical structures is one of the great challenges in nanochemistry and materials science. We report a facile and simple chemical conversion route to fabricate 3D hierarchical nanosheet-based ZnSe microspheres by using 2D inorganic-organic hybrid ZnSe-DETA (DETA = diethylenetriamine) nanosheets as the starting precursors. The conversion mechanism involves the controlled depletion of the organic-component (DETA) from the hybrid precursors and the subsequent self-assembly of the remnant inorganic-component (ZnSe). The transformation reaction of ZnSe-DETA nanosheets is mainly influenced by the concentration of DETA in the reaction solution. We demonstrated that this organic-component depletion method could be extended to the synthesis of other hierarchical structures of metal sulfides. In addition, the obtained

  18. 3D-graphite structure

    SciTech Connect

    Belenkov, E. A. Ali-Pasha, V. A.

    2011-01-15

    The structure of clusters of some new carbon 3D-graphite phases have been calculated using the molecular-mechanics methods. It is established that 3D-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.

  19. Novel utilization of 3D technology and the hybrid operating theatre: Peri-operative assessment of posterior sterno-clavicular dislocation using cone beam CT

    SciTech Connect

    Crowhurst, James A; Campbell, Douglas; Whitby, Mark; Pathmanathan, Pavthrun

    2013-06-15

    A patient with a medial and posterior dislocation of the right sterno-clavicular (SC) joint and displacement of the trachea and brachiocephalic artery by the medial head of the clavicle underwent general anaesthetic in the operating theatre for an open reduction procedure. The surgeon initially attempted a closed reduction, but this required imaging to check SC alignment. The patient was transferred to an adjacent hybrid operating theatre for imaging. Cone beam computed tomography (CBCT) was performed, which successfully demonstrated a significant reduction in the dislocation of the SC joint. The trachea and brachiocephalic artery were no longer compressed or displaced. This case study demonstrates an alternative to the patient being transferred to the medical imaging department for multi-slice CT. It also describes a novel use of the hybrid operating theatre and its CBCT capabilities.

  20. Ultra-long Pt nanolawns supported on TiO2-coated carbon fibers as 3D hybrid catalyst for methanol oxidation

    PubMed Central

    2012-01-01

    In this study, TiO2 thin film photocatalyst on carbon fibers was used to synthesize ultra-long single crystalline Pt nanowires via a simple photoreduction route (thermally activated photoreduction). It also acted as a co-catalytic material with Pt. Taking advantage of the high-aspect ratio of the Pt nanostructure as well as the excellent catalytic activity of TiO2, this hybrid structure has the great potential as the active anode in direct methanol fuel cells. The electrochemical results indicate that TiO2 is capable of transforming CO-like poisoning species on the Pt surface during methanol oxidation and contributes to a high CO tolerance of this Pt nanowire/TiO2 hybrid structure. PMID:22546416

  1. Novel utilization of 3D technology and the hybrid operating theatre: Peri-operative assessment of posterior sterno-clavicular dislocation using cone beam CT

    PubMed Central

    Crowhurst, James A; Campbell, Douglas; Whitby, Mark; Pathmanathan, Pavthrun

    2013-01-01

    A patient with a medial and posterior dislocation of the right sterno-clavicular (SC) joint and displacement of the trachea and brachiocephalic artery by the medial head of the clavicle underwent general anaesthetic in the operating theatre for an open reduction procedure. The surgeon initially attempted a closed reduction, but this required imaging to check SC alignment. The patient was transferred to an adjacent hybrid operating theatre for imaging. Cone beam computed tomography (CBCT) was performed, which successfully demonstrated a significant reduction in the dislocation of the SC joint. The trachea and brachiocephalic artery were no longer compressed or displaced. This case study demonstrates an alternative to the patient being transferred to the medical imaging department for multi-slice CT. It also describes a novel use of the hybrid operating theatre and its CBCT capabilities. PMID:26229610

  2. 3D TiO2@Ni(OH)2 Core-shell Arrays with Tunable Nanostructure for Hybrid Supercapacitor Application

    PubMed Central

    Ke, Qingqing; Zheng, Minrui; Liu, Huajun; Guan, Cao; Mao, Lu; Wang, John

    2015-01-01

    Three dimensional hierarchical nanostructures have attracted great attention for electrochemical energy storage applications. In this work, self-supported TiO2@Ni(OH)2 core-shell nanowire arrays are prepared on carbon fiber paper via the combination of hydrothermal synthesis and chemical bath deposition. In this core-shell hybrid, the morphology and wall size of the interconnected nanoflake shell of Ni(OH)2 can be tuned through adjusting the concentration of ammonia solution. Heterogeneous nucleation and subsequent oriented crystal growth are identified to be the synthesis mechanism affecting the nanostructure of the shell material, which consequently determines the electrochemical performance in both energy storage and charge transfer. Superior capabilities of 264 mAhg−1 at 1 A g−1 and 178 mAh g−1 at 10 A g−1 are achieved with the core-shell hybrids of the optimized structure. The asymmetric supercapacitor prototype, comprising of TiO2@Ni(OH)2 as the anode and mesoporous carbons (MCs) as the cathode, is shown to exhibit superior electrochemical performance with high energy and power densities. The present work provides a clear illustration of the structure-property relationship in nanocrystal synthesis and offers a potential strategy to enhance the battery type Ni(OH)2 electrode in a hybrid supercapacitor device. PMID:26353970

  3. The Interaction of the Solar Wind with Solar Probe Plus - 3D Hybrid Simulation. Report 2: The Study for the Distance 9.5Rs

    NASA Technical Reports Server (NTRS)

    Lipatov, Alexander S.; Sittler, Edward C.; Hartle, Richard E.; Cooper, John F.

    2010-01-01

    Our paper is a 2.5D and 3D numerical plasma models of the interaction of the solar wind (SW) with the Solar Probe Plus spacecraft (SPPSC). These results should be interpreted as a basic plasma model for which the derived SW interaction with spacecraft (SC) could have consequences for both plasma wave and electron plasma measurements on board SC in the inner heliosphere. We observe an excitation of the low frequency Alfven and whistler type wave directed by the magnetic field with an amplitude of the electromagnetic field oscillation about of (0.015-0.06) V/m. The compression waves and the jumps in an electric field with an amplitude of about 1.5 V/m and (12-18) V/m were also observed. The observed strong electromagnetic perturbations may be a crucial point in the electromagnetic measurements, which were planned in future Solar Probe Plus mission.

  4. Hybrid grid-particle methods and Penalization: A Sherman-Morrison-Woodbury approach to compute 3D viscous flows using FFT

    NASA Astrophysics Data System (ADS)

    Chatelin, Robin; Poncet, Philippe

    2014-07-01

    Particle methods are very convenient to compute transport equations in fluid mechanics as their computational cost is linear and they are not limited by convection stability conditions. To achieve large 3D computations the method must be coupled to efficient algorithms for velocity computations, including a good treatment of non-homogeneities and complex moving geometries. The Penalization method enables to consider moving bodies interaction by adding a term in the conservation of momentum equation. This work introduces a new computational algorithm to solve implicitly in the same step the Penalization term and the Laplace operators, since explicit computations are limited by stability issues, especially at low Reynolds number. This computational algorithm is based on the Sherman-Morrison-Woodbury formula coupled to a GMRES iterative method to reduce the computations to a sequence of Poisson problems: this allows to formulate a penalized Poisson equation as a large perturbation of a standard Poisson, by means of algebraic relations. A direct consequence is the possibility to use fast solvers based on Fast Fourier Transforms for this problem with good efficiency from both the computational and the memory consumption point of views, since these solvers are recursive and they do not perform any matrix assembling. The resulting fluid mechanics computations are very fast and they consume a small amount of memory, compared to a reference solver or a linear system resolution. The present applications focus mainly on a coupling between transport equation and 3D Stokes equations, for studying biological organisms motion in a highly viscous flows with variable viscosity.

  5. Time-dependent distribution functions and resulting synthetic NPA spectra in C-Mod calculated with the CQL3D-Hybrid-FOW, AORSA full-wave, and DC Lorentz codes

    NASA Astrophysics Data System (ADS)

    Harvey, R. W.; Petrov, Yu.; Jaeger, E. F.; Berry, L. A.; Bonoli, P. T.; Bader, A.

    2015-12-01

    A time-dependent simulation of C-Mod pulsed TCRF power is made obtaining minority hydrogen ion distributions with the CQL3D-Hybrid-FOW finite-orbit-width Fokker-Planck code. Cyclotron-resonant TCRF fields are calculated with the AORSA full wave code. The RF diffusion coefficients used in CQL3D are obtained with the DC Lorentz gyro-orbit code for perturbed particle trajectories in the combined equilibrium and TCRF electromagnetic fields. Prior results with a zero-banana-width simulation using the CQL3D/AORSA/DC time-cycles showed a pronounced enhancement of the H distribution in the perpendicular velocity direction compared to results obtained from Stix's quasilinear theory, and this substantially increased the rampup rate of the observed vertically-viewed neutral particle analyzer (NPA) flux, in general agreement with experiment. However, ramp down of the NPA flux after the pulse, remained long compared to the experiment. The present study compares the new FOW results, including relevant gyro-radius effects, to determine the importance of these new effects on the the NPA time-dependence.

  6. Converting 2D inorganic-organic ZnSe-DETA hybrid nanosheets into 3D hierarchical nanosheet-based ZnSe microspheres with enhanced visible-light-driven photocatalytic performances.

    PubMed

    Wu, Xuan; Xu, Rui; Zhu, Rongjiao; Wu, Rui; Zhang, Bin

    2015-06-07

    Engineering two-dimensional (2D) nanosheets into three-dimensional (3D) hierarchical structures is one of the great challenges in nanochemistry and materials science. We report a facile and simple chemical conversion route to fabricate 3D hierarchical nanosheet-based ZnSe microspheres by using 2D inorganic-organic hybrid ZnSe-DETA (DETA = diethylenetriamine) nanosheets as the starting precursors. The conversion mechanism involves the controlled depletion of the organic-component (DETA) from the hybrid precursors and the subsequent self-assembly of the remnant inorganic-component (ZnSe). The transformation reaction of ZnSe-DETA nanosheets is mainly influenced by the concentration of DETA in the reaction solution. We demonstrated that this organic-component depletion method could be extended to the synthesis of other hierarchical structures of metal sulfides. In addition, the obtained hierarchical nanosheet-based ZnSe microspheres exhibited outstanding performance in visible light photocatalytic degradation of methyl orange and were highly active for photocatalytic H2 production.

  7. Global 3-D imaging of mantle electrical conductivity based on inversion of observatory C-responses - I. An approach and its verification

    NASA Astrophysics Data System (ADS)

    Kuvshinov, Alexey; Semenov, Alexey

    2012-06-01

    We present a novel frequency-domain inverse solution to recover the 3-D electrical conductivity distribution in the mantle. The solution is based on analysis of local C-responses. It exploits an iterative gradient-type method - limited-memory quasi-Newton method - for minimizing the penalty function consisting of data misfit and regularization terms. The integral equation code is used as a forward engine to calculate responses and data misfit gradients during inversion. An adjoint approach is implemented to compute misfit gradients efficiently. Further improvements in computational load come from parallelizing the scheme with respect to frequencies, and from setting the most time-consuming part of the forward calculations - calculation of Green's tensors - apart from the inversion loop. Convergence, performance, and accuracy of our 3-D inverse solution are demonstrated with a synthetic numerical example. A companion paper applies the strategy set forth here to real data.

  8. AE3D

    SciTech Connect

    Spong, Donald A

    2016-06-20

    AE3D solves for the shear Alfven eigenmodes and eigenfrequencies in a torodal magnetic fusion confinement device. The configuration can be either 2D (e.g. tokamak, reversed field pinch) or 3D (e.g. stellarator, helical reversed field pinch, tokamak with ripple). The equations solved are based on a reduced MHD model and sound wave coupling effects are not currently included.

  9. Nano-spatial parameters from 3D to 2D lattice dimensionality by organic variant in [ZnCl4]- [R]+ hybrid materials: Structure, architecture-lattice dimensionality, microscopy, optical Eg and PL correlations

    NASA Astrophysics Data System (ADS)

    Kumar, Ajit; Verma, Sanjay K.; Alvi, P. A.; Jasrotia, Dinesh

    2016-04-01

    The nanospatial morphological features of [ZnCl]- [C5H4NCH3]+ hybrid derivative depicts 28 nm granular size and 3D spreader shape packing pattern as analyzed by FESEM and single crystal XRD structural studies. The organic moiety connect the inorganic components through N-H+…Cl- hydrogen bond to form a hybrid composite, the replacement of organic derivatives from 2-methylpyridine to 2-Amino-5-choloropyridine results the increase in granular size from 28nm to 60nm and unit cell packing pattern from 3D-2D lattice dimensionality along ac plane. The change in optical energy direct band gap value from 3.01eV for [ZnCl]- [C5H4NCH3]+ (HM1) to 3.42eV for [ZnCl]- [C5H5ClN2]+ (HM2) indicates the role of organic moiety in optical properties of hybrid materials. The photoluminescence emission spectra is observed in the wavelength range of 370 to 600 nm with maximum peak intensity of 9.66a.u. at 438 nm for (HM1) and 370 to 600 nm with max peak intensity of 9.91 a.u. at 442 nm for (HM2), indicating that the emission spectra lies in visible range. PL excitation spectra depicts the maximum excitation intensity [9.8] at 245.5 nm for (HM1) and its value of 9.9 a.u. at 294 nm, specify the excitation spectra lies in UV range. Photoluminescence excitation spectra is observed in the wavelength range of 280 to 350 nm with maximum peak intensity of 9.4 a.u. at 285.5 nm and 9.9 a.u. at 294 and 297 nm, indicating excitation in the UV spectrum. Single crystal growth process and detailed physiochemical characterization such as XRD, FESEM image analysis photoluminescence property reveals the structure stability with non-covalent interactions, lattice dimensionality (3D-2D) correlations interweaving into the design of inorganic-organic hybrid materials.

  10. An efficient hybrid MLFMA-FFT solver for the volume integral equation in case of sparse 3D inhomogeneous dielectric scatterers

    SciTech Connect

    Zaeytijd, J. de Bogaert, I.; Franchois, A.

    2008-07-01

    Electromagnetic scattering problems involving inhomogeneous objects can be numerically solved by applying a Method of Moments discretization to the volume integral equation. For electrically large problems, the iterative solution of the resulting linear system is expensive, both computationally and in memory use. In this paper, a hybrid MLFMA-FFT method is presented, which combines the fast Fourier transform (FFT) method and the High Frequency Multilevel Fast Multipole Algorithm (MLFMA) in order to reduce the cost of the matrix-vector multiplications needed in the iterative solver. The method represents the scatterers within a set of possibly disjoint identical cubic subdomains, which are meshed using a uniform cubic grid. This specific mesh allows for the application of FFTs to calculate the near interactions in the MLFMA and reduces the memory cost considerably, since the aggregation and disaggregation matrices of the MLFMA can be reused. Additional improvements to the general MLFMA framework, such as an extention of the FFT interpolation scheme of Sarvas et al. from the scalar to the vectorial case in combination with a more economical representation of the radiation patterns on the lowest level in vector spherical harmonics, are proposed and the choice of the subdomain size is discussed. The hybrid method performs better in terms of speed and memory use on large sparse configurations than both the FFT method and the HF MLFMA separately and it has lower memory requirements on general large problems. This is illustrated on a number of representative numerical test cases.

  11. DNA biosensing with 3D printing technology.

    PubMed

    Loo, Adeline Huiling; Chua, Chun Kiang; Pumera, Martin

    2017-01-16

    3D printing, an upcoming technology, has vast potential to transform conventional fabrication processes due to the numerous improvements it can offer to the current methods. To date, the employment of 3D printing technology has been examined for applications in the fields of engineering, manufacturing and biological sciences. In this study, we examined the potential of adopting 3D printing technology for a novel application, electrochemical DNA biosensing. Metal 3D printing was utilized to construct helical-shaped stainless steel electrodes which functioned as a transducing platform for the detection of DNA hybridization. The ability of electroactive methylene blue to intercalate into the double helix structure of double-stranded DNA was then exploited to monitor the DNA hybridization process, with its inherent reduction peak serving as an analytical signal. The designed biosensing approach was found to demonstrate superior selectivity against a non-complementary DNA target, with a detection range of 1-1000 nM.

  12. Stable Li Plating/Stripping Electrochemistry Realized by a Hybrid Li Reservoir in Spherical Carbon Granules with 3D Conducting Skeletons.

    PubMed

    Ye, Huan; Xin, Sen; Yin, Ya-Xia; Li, Jin-Yi; Guo, Yu-Guo; Wan, Li-Jun

    2017-04-14

    Lithium metal is a promising battery anode. However, inhomogeneous mass and charge transfers across the Li/electrolyte interface result in formation of dendritic Li and "dead" Li, and an unstable solid electrolyte interphase, which incur serious problems to impede its service in rechargeable batteries. Here, we show that the above problems can be mitigated by regulating the interfacial mass/charge transfer. The key to our strategy is hybrid Li storage in onion-like, graphitized spherical C granules wired on a three-dimensional conducting skeleton, which enhances the negativity of surface charge of the C host to contribute to a uniform Li plating while also forming stable Li/C intercalation compounds to offset any irreversible Li loss during cycling. As a result, the anode shows a suppressed dendrite formation and a high Li utilization >95%, enabling a practical Li battery to strike a long lifespan of 1000 cycles at a surplus Li of merely 5%.

  13. Effects of H+, He+ ion reflection at the lunar surface and pickup ion dynamics in case of oblique/quasi-parallel magnetic field: 3-D hybrid kinetic modeling

    NASA Astrophysics Data System (ADS)

    Lipatov, A. S.; Cooper, J. F.; Sittler, E. C.; Hartle, R. E.; Sarantos, M.

    2013-12-01

    The hybrid kinetic model used here supports comprehensive simulation of the interaction between different spatial and energetic elements of the moon-solar wind-magnetosphere of the Earth system. This involves variable upstream magnetic field and solar wind plasma, including energetic ions, electrons, and neutral atoms. This capability is critical to improved interpretation of existing measurements for surface and atmospheric composition from previous missions and planning future missions. Recently, MAP-PAGE-IMA (Plasma energy Angle and Composition Experiment, and Ion Mass Analyzer) onboard Japanese lunar orbiter SELENE (KAGUYA) detected Moon originating ions at 100 km altitude. Ion species of H+, He++, He+, C+, O+, Na+, K+, and Ar+ were definitively identified. The first portion of our modeling devotes to a study of the H+, H2+, He+, Na+ pickup ion dynamics in cases of flow with a oblique and quasi-parallel magnetic field. In the second series of modeling we also take into account collisions between ions and the surface of the moon and further sputtering of fragments from the surface of the moon. The ion reflection at the lunar surface is also responsible for wave activity in the upstream flow. The solar wind parameters are chosen from ARTEMIS observations. The hybrid kinetic model allows us to take into account the finite gyroradius effects of pickup ions and to estimate correctly the ions velocity distribution and the fluxes along the magnetic field. Modeling shows the asymmetric Mach cone, pickup and reflected ion tails, and presents another type of lunar-solar wind interaction. Our simulation may be also important for the study of the interaction between the solar wind and very weak comets, Mercury and Pluto.

  14. Investigation of storm time magnetotail and ion injection using three-dimensional global hybrid simulation

    NASA Astrophysics Data System (ADS)

    Lin, Y.; Wang, X. Y.; Lu, S.; Perez, J. D.; Lu, Q.

    2014-09-01

    Dynamics of the near-Earth magnetotail associated with substorms during a period of extended southward interplanetary magnetic field is studied using a three-dimensional (3-D) global hybrid simulation model that includes both the dayside and nightside magnetosphere, for the first time, with physics from the ion kinetic to the global Alfvénic convection scales. It is found that the dayside reconnection leads to the penetration of the dawn-dusk electric field through the magnetopause and thus a thinning of the plasma sheet, followed by the magnetotail reconnection with 3-D, multiple flux ropes. Ion kinetic physics is found to play important roles in the magnetotail dynamics, which leads to the following results: (1) Hall electric fields in the thin current layer cause a systematic dawnward ion drift motion and thus a dawn-dusk asymmetry of the plasma sheet with a higher (lower) density on the dawnside (duskside). Correspondingly, more reconnection occurs on the duskside. Bidirectional fast ions are generated due to acceleration in reconnection, and more high-speed earthward flow injections are found on the duskside than the dawnside. Such finding of the dawn-dusk asymmetry is consistent with recent satellite observations. (2) The injected ions undergo the magnetic gradient and curvature drift in the dipole-like field, forming a ring current. (3) Ion particle distributions reveal multiple populations/beams at various distances in the tail. (4) Dipolarization of the tail magnetic field takes place due to the pileup of the injected magnetic fluxes and thermal pressure of injected ions, where the fast earthward flow is stopped. Oscillation of the dipolarization front is developed at the fast-flow braking, predominantly on the dawnside. (5) Kinetic compressional wave turbulence is present around the dipolarization front. The cross-tail currents break into small-scale structures with k⟂ρi˜1, where k⟂ is the perpendicular wave number. A sharp dip of magnetic field

  15. 3-D Seismic Interpretation

    NASA Astrophysics Data System (ADS)

    Moore, Gregory F.

    2009-05-01

    This volume is a brief introduction aimed at those who wish to gain a basic and relatively quick understanding of the interpretation of three-dimensional (3-D) seismic reflection data. The book is well written, clearly illustrated, and easy to follow. Enough elementary mathematics are presented for a basic understanding of seismic methods, but more complex mathematical derivations are avoided. References are listed for readers interested in more advanced explanations. After a brief introduction, the book logically begins with a succinct chapter on modern 3-D seismic data acquisition and processing. Standard 3-D acquisition methods are presented, and an appendix expands on more recent acquisition techniques, such as multiple-azimuth and wide-azimuth acquisition. Although this chapter covers the basics of standard time processing quite well, there is only a single sentence about prestack depth imaging, and anisotropic processing is not mentioned at all, even though both techniques are now becoming standard.

  16. Radiochromic 3D Detectors

    NASA Astrophysics Data System (ADS)

    Oldham, Mark

    2015-01-01

    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 3D radiochromic dosimetry has become possible. In this article we review recent developments and the current state-of-the-art of 3D radiochromic dosimetry, and the potential for a more comprehensive solution for the verification of complex radiation therapy treatments, and 3D dose measurement in general.

  17. Bootstrapping 3D fermions

    DOE PAGES

    Iliesiu, Luca; Kos, Filip; Poland, David; ...

    2016-03-17

    We study the conformal bootstrap for a 4-point function of fermions <ψψψψ> in 3D. We first introduce an embedding formalism for 3D 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 CT. We observe features in our bounds that coincide with scaling dimensions in the GrossNeveu models at large N. Finally, we also speculate that other features could coincide with a fermionic CFT containing no relevant scalar operators.

  18. Bootstrapping 3D fermions

    SciTech Connect

    Iliesiu, Luca; Kos, Filip; Poland, David; Pufu, Silviu S.; Simmons-Duffin, David; Yacoby, Ran

    2016-03-17

    We study the conformal bootstrap for a 4-point function of fermions <ψψψψ> in 3D. We first introduce an embedding formalism for 3D 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 CT. We observe features in our bounds that coincide with scaling dimensions in the GrossNeveu models at large N. Finally, we also speculate that other features could coincide with a fermionic CFT containing no relevant scalar operators.

  19. Segmentation of 3D microPET images of the rat brain via the hybrid gaussian mixture method with kernel density estimation.

    PubMed

    Chen, Tai-Been; Chen, Jyh-Cheng; Lu, Henry Horng-Shing

    2012-01-01

    Segmentation of positron emission tomography (PET) is typically achieved using the K-Means method or other approaches. In preclinical and clinical applications, the K-Means method needs a prior estimation of parameters such as the number of clusters and appropriate initialized values. This work segments microPET images using a hybrid method combining the Gaussian mixture model (GMM) with kernel density estimation. Segmentation is crucial to registration of disordered 2-deoxy-2-fluoro-D-glucose (FDG) accumulation locations with functional diagnosis and to estimate standardized uptake values (SUVs) of region of interests (ROIs) in PET images. Therefore, simulation studies are conducted to apply spherical targets to evaluate segmentation accuracy based on Tanimoto's definition of similarity. The proposed method generates a higher degree of similarity than the K-Means method. The PET images of a rat brain are used to compare the segmented shape and area of the cerebral cortex by the K-Means method and the proposed method by volume rendering. The proposed method provides clearer and more detailed activity structures of an FDG accumulation location in the cerebral cortex than those by the K-Means method.

  20. Syntheses, structures and photocatalytic properties of five new praseodymium-antimony oxochlorides: from discrete clusters to 3D inorganic-organic hybrid racemic compounds.

    PubMed

    Zou, Guo-Dong; Wang, Ze-Ping; Song, Ying; Hu, Bing; Huang, Xiao-Ying

    2014-07-14

    Five novel praseodymium-antimony oxochloride (Pr-Sb-O-Cl) cluster-based compounds, namely (2-MepyH)2[Fe(1,10-phen)3]2[Pr4Sb12O18Cl14.6(OH)2.4(Hsal)]·H2O (1), (2-MepyH)2[Fe(1,10-phen)3]4{[Pr4Sb12O18Cl13.5(OH)0.5](bcpb)2[Pr4Sb12O18Cl13.5(OH)0.5]}·42H2O (2), (3-MepyH)2[Fe(1,10-phen)3]{[Pr4Sb12O18Cl13(H2O)2](bcpb)}·2(3-Mepy)·3H2O (3), [Fe(1,10-phen)3]2{[Pr4Sb12O18Cl10(H2O)2](bcpb)2}·3(3-Mepy)·13H2O (4), and (2-MepyH)6[Fe(1,10-phen)3]10{[Pr4Sb12O18Cl13(OH)2]2[Pr4Sb12O18Cl9][Pr4Sb12O18Cl9(OH)2]2(Hpdc)10(pdc)2}·110H2O (5) (2-Mepy = 2-methylpyridine, 3-Mepy = 3-methylpyridine, 1,10-phen = 1,10-phenanthroline, H2sal = salicylic acid, H3bcpb = 3,5-bis(4-carboxyphenoxy)benzoic acid, H3pdc = 3,5-pyrazoledicarboxylic acid) have been solvothermally synthesized and structurally characterized. Compound 1 is the first zero-dimensional (0D) Pr-Sb-O-Cl cluster decorated by an organic ligand. Compounds 2-4 are constructed from the same H3bcpb ligands but adopt different structures: 2 represents a rare example of a one-dimensional (1D) nanotubular structure based on high-nuclearity clusters; 3 exhibits a two-dimensional (2D) mono-layered structure, in which left-handed and right-handed helical chains are alternately arranged, while 4 features a double-layered structure with an unprecedented (3,3,6)-connected 3-nodal topological net. Compound 5 is a unique three-dimensional (3D) 2-fold interpenetrating racemic compound, simultaneously containing three kinds of Pr-Sb-O-Cl-pdc clusters. UV-light photocatalytic H2 evolution activity was observed for compound 3 with Pt as a co-catalyst and MeOH as a sacrificial electron donor. In addition, the magnetic properties of compounds 1 and 5 are also studied.

  1. Origin of small barriers in Jahn-Teller systems: quantifying the role of 3d-4s hybridization in the model system NaCl:Ni+.

    PubMed

    Barriuso, M T; Ortiz-Sevilla, B; Aramburu, J A; García-Fernández, P; García-Lastra, J M; Moreno, M

    2013-08-19

    Despite its relevance, the microscopic origin of the energy barrier, B, between the compressed and elongated geometries of Jahn-Teller (JT) systems is not well understood yet because of a lack of quantitative data about its various contributions. Seeking to clear up this matter, we have carried out both periodic and cluster ab initio calculations on the model system NaCl:Ni(+). This system is particularly puzzling because, according to experimental data, its barrier is much smaller than that for other d(9) and d(7) ions in similar lattices. All calculations performed on the model system lead, in fact, to values |B| ≤ 160 cm(-1), which are certainly smaller than B = 500 cm(-1) derived for NaCl:M(2+) (M = Ag, Rh) or B = 1024 cm(-1) obtained for KCl:Ag(2+). As a salient feature, analysis of calculations carried out as a function of the Qθ (∼3z(2) - r(2)) coordinate unveils the microscopic origin of the barrier. It is quantitatively proven that the elongated geometry observed for NaCl:Ni(+) is due to the 3d-4s vibronic admixture, which is slightly larger than the anharmonicity in the eg JT mode that favors a compressed geometry. The existence of these two competing mechanisms explains the low value of B for the model system, contrary to cases where the complex formed by d(9) or d(7) ions is elastically decoupled from the host lattice. Although the magnitude of B for NaCl:Ni(+) is particularly small, the tunneling splitting, 3Γ, is estimated to be below 9 cm(-1), thus explaining why the coherence is easily destroyed by random strains and thus a static JT effect is observed experimentally. As a main conclusion, the barrier in JT systems cannot be understood neglecting the tiny changes of the electronic density involved in small distortions. The present calculations reasonably explain the experimental g tensor of NaCl:Ni(+), pointing out that the d-d transitions in NiCl6(5-) are much smaller than those for CuCl6(4-) and the optical electronegativity of Ni(+) is only

  2. Venus in 3D

    NASA Technical Reports Server (NTRS)

    Plaut, Jeffrey J.

    1993-01-01

    Stereographic images of the surface of Venus which enable geologists to reconstruct the details of the planet's evolution are discussed. The 120-meter resolution of these 3D images make it possible to construct digital topographic maps from which precise measurements can be made of the heights, depths, slopes, and volumes of geologic structures.

  3. 3D photoacoustic imaging

    NASA Astrophysics Data System (ADS)

    Carson, Jeffrey J. L.; Roumeliotis, Michael; Chaudhary, Govind; Stodilka, Robert Z.; Anastasio, Mark A.

    2010-06-01

    Our group has concentrated on development of a 3D photoacoustic imaging system for biomedical imaging research. The technology employs a sparse parallel detection scheme and specialized reconstruction software to obtain 3D optical images using a single laser pulse. With the technology we have been able to capture 3D movies of translating point targets and rotating line targets. The current limitation of our 3D photoacoustic imaging approach is its inability ability to reconstruct complex objects in the field of view. This is primarily due to the relatively small number of projections used to reconstruct objects. However, in many photoacoustic imaging situations, only a few objects may be present in the field of view and these objects may have very high contrast compared to background. That is, the objects have sparse properties. Therefore, our work had two objectives: (i) to utilize mathematical tools to evaluate 3D photoacoustic imaging performance, and (ii) to test image reconstruction algorithms that prefer sparseness in the reconstructed images. Our approach was to utilize singular value decomposition techniques to study the imaging operator of the system and evaluate the complexity of objects that could potentially be reconstructed. We also compared the performance of two image reconstruction algorithms (algebraic reconstruction and l1-norm techniques) at reconstructing objects of increasing sparseness. We observed that for a 15-element detection scheme, the number of measureable singular vectors representative of the imaging operator was consistent with the demonstrated ability to reconstruct point and line targets in the field of view. We also observed that the l1-norm reconstruction technique, which is known to prefer sparseness in reconstructed images, was superior to the algebraic reconstruction technique. Based on these findings, we concluded (i) that singular value decomposition of the imaging operator provides valuable insight into the capabilities of

  4. High-Pressure Single-Crystal Structures of 3D Lead-Halide Hybrid Perovskites and Pressure Effects on their Electronic and Optical Properties

    PubMed Central

    2016-01-01

    We report the first high-pressure single-crystal structures of hybrid perovskites. The crystalline semiconductors (MA)PbX3 (MA = CH3NH3+, X = Br– or I–) afford us the rare opportunity of understanding how compression modulates their structures and thereby their optoelectronic properties. Using atomic coordinates obtained from high-pressure single-crystal X-ray diffraction we track the perovskites’ precise structural evolution upon compression. These structural changes correlate well with pressure-dependent single-crystal photoluminescence (PL) spectra and high-pressure bandgaps derived from density functional theory. We further observe dramatic piezochromism where the solids become lighter in color and then transition to opaque black with compression. Indeed, electronic conductivity measurements of (MA)PbI3 obtained within a diamond-anvil cell show that the material’s resistivity decreases by 3 orders of magnitude between 0 and 51 GPa. The activation energy for conduction at 51 GPa is only 13.2(3) meV, suggesting that the perovskite is approaching a metallic state. Furthermore, the pressure response of mixed-halide perovskites shows new luminescent states that emerge at elevated pressures. We recently reported that the perovskites (MA)Pb(BrxI1–x)3 (0.2 < x < 1) reversibly form light-induced trap states, which pin their PL to a low energy. This may explain the low voltages obtained from solar cells employing these absorbers. Our high-pressure PL data indicate that compression can mitigate this PL redshift and may afford higher steady-state voltages from these absorbers. These studies show that pressure can significantly alter the transport and thermodynamic properties of these technologically important semiconductors. PMID:27163050

  5. High-Pressure Single-Crystal Structures of 3D Lead-Halide Hybrid Perovskites and Pressure Effects on their Electronic and Optical Properties.

    PubMed

    Jaffe, Adam; Lin, Yu; Beavers, Christine M; Voss, Johannes; Mao, Wendy L; Karunadasa, Hemamala I

    2016-04-27

    We report the first high-pressure single-crystal structures of hybrid perovskites. The crystalline semiconductors (MA)PbX3 (MA = CH3NH3 (+), X = Br(-) or I(-)) afford us the rare opportunity of understanding how compression modulates their structures and thereby their optoelectronic properties. Using atomic coordinates obtained from high-pressure single-crystal X-ray diffraction we track the perovskites' precise structural evolution upon compression. These structural changes correlate well with pressure-dependent single-crystal photoluminescence (PL) spectra and high-pressure bandgaps derived from density functional theory. We further observe dramatic piezochromism where the solids become lighter in color and then transition to opaque black with compression. Indeed, electronic conductivity measurements of (MA)PbI3 obtained within a diamond-anvil cell show that the material's resistivity decreases by 3 orders of magnitude between 0 and 51 GPa. The activation energy for conduction at 51 GPa is only 13.2(3) meV, suggesting that the perovskite is approaching a metallic state. Furthermore, the pressure response of mixed-halide perovskites shows new luminescent states that emerge at elevated pressures. We recently reported that the perovskites (MA)Pb(Br x I1-x )3 (0.2 < x < 1) reversibly form light-induced trap states, which pin their PL to a low energy. This may explain the low voltages obtained from solar cells employing these absorbers. Our high-pressure PL data indicate that compression can mitigate this PL redshift and may afford higher steady-state voltages from these absorbers. These studies show that pressure can significantly alter the transport and thermodynamic properties of these technologically important semiconductors.

  6. Global magnetosphere-like 3D structure formation in kinetics by hot magnetized plasma flow characterized by shape of the particle distribution function

    NASA Astrophysics Data System (ADS)

    Gubchenko, Vladimir

    The task was to provide an analytical elementary magnetosphere-like model in kinetics for verification of the 3D EM PIC codes created for space/aerospace and HED plasmas applications. Kinetic approach versus cold MHD approach takes into account different behavior in the EM fields of resonant and non resonant particles in the velocity phase space, which appears via shape characteristics of the particle velocity distribution function (PVDF) and via the spatial dispersion effect forming the collisionless dissipation in the EM fields. The external flow is a hot collisionless plasma characterized by the particle velocity distribution function (PVDF) with different shapes: Maxwellian, kappa, etc. The flow is in a “hot regime”: it can be supersonic but its velocity remains less the thermal velocity of the electrons. The “internal” part of the magnetosphere formed by trapped particles is the prescribed 3D stationary magnetization considered as a spherical “quasiparticle” with internal magnetodipole and toroidal moments represented as a broadband EM driver. We obtain after the linearization of Vlasov/Maxwell equations a self-consistent 3D large scale kinetic solution of the classic problem. Namely, we: model the “outer” part of the magnetosphere formed by external hot plasma flow of the flyby particles. Solution of the Vlasov equation expressed via a tensor of dielectric permittivity of nonmagnetized and magnetized flowing plasma. Here, we obtain the direct kinetic dissipative effect of the magnetotail formation and the opposite diamagnetic effect of the magnetosphere “dipolization”. We get MHD wave cone in flow magnetized by external guiding magnetic (GM) field. Magnetosphere in our consideration is a 3D dissipative “wave” package structure of the skinned EM fields formed by the “waves” excited at frequency bands where we obtain negative values and singularities (resonances) of squared EM refractive index of the cold plasma. The hot regime

  7. 3D nanopillar optical antenna photodetectors.

    PubMed

    Senanayake, Pradeep; Hung, Chung-Hong; Shapiro, Joshua; Scofield, Adam; Lin, Andrew; Williams, Benjamin S; Huffaker, Diana L

    2012-11-05

    We demonstrate 3D surface plasmon photoresponse in nanopillar arrays resulting in enhanced responsivity due to both Localized Surface Plasmon Resonances (LSPRs) and Surface Plasmon Polariton Bloch Waves (SPP-BWs). The LSPRs are excited due to a partial gold shell coating the nanopillar which acts as a 3D Nanopillar Optical Antenna (NOA) in focusing light into the nanopillar. Angular photoresponse measurements show that SPP-BWs can be spectrally coincident with LSPRs to result in a x2 enhancement in responsivity at 1180 nm. Full-wave Finite Difference Time Domain (FDTD) simulations substantiate both the spatial and spectral coupling of the SPP-BW / LSPR for enhanced absorption and the nature of the LSPR. Geometrical control of the 3D NOA and the self-aligned metal hole lattice allows the hybridization of both localized and propagating surface plasmon modes for enhanced absorption. Hybridized plasmonic modes opens up new avenues in optical antenna design in nanoscale photodetectors.

  8. Computation of the 3D kinematics in a global frame over a 40m-long pathway using a rolling motion analysis system.

    PubMed

    Begon, Mickaël; Colloud, Floren; Fohanno, Vincent; Bahuaud, Pascal; Monnet, Tony

    2009-12-11

    A rolling motion analysis system has been purpose-built to acquire an accurate three-dimensional kinematics of human motion with large displacement. Using this device, the kinematics is collected in a local frame associated with the rolling motion analysis system. The purpose of this paper is to express the local kinematics of a subject walking on a 40 m-long pathway in a global system of co-ordinates. One participant performed five trials of walking while he was followed by a rolling eight camera optoelectronic motion analysis system. The kinematics of the trials were reconstructed in the global frame using two different algorithms and 82 markers placed on the floor organized in two parallel and horizontal lines. The maximal error ranged from 0.033 to 0.187 m (<0.5% of the volume diagonal). As a result, this device is accurate enough for acquiring the kinematics of cyclic activities with large displacements in ecological environment.

  9. Assessment of Anthropogenic and Climatic Impacts on the Global Carbon Cycle Using a 3-D Model Constrained by Isotopic Carbon Measurements and Remote Sensing of Vegetation

    NASA Technical Reports Server (NTRS)

    Keeling, Charles D.; Piper, S. C.

    1998-01-01

    Our original proposal called for improved modeling of the terrestrial biospheric carbon cycle, specifically using biome-specific process models to account for both the energy and water budgets of plant growth, to facilitate investigations into recent changes in global atmospheric CO2 abundance and regional distribution. The carbon fluxes predicted by these models were to be incorporated into a global model of CO2 transport to establish large-scale regional fluxes of CO2 to and from the terrestrial biosphere subject to constraints imposed by direct measurements of atmospheric CO2 and its 13C/12C isotopic ratio. Our work was coordinated with a NASA project (NASA NAGW-3151) at the University of Montana under the direction of Steven Running, and was partially funded by the Electric Power Research Institute. The primary objective of this project was to develop and test the Biome-BGC model, a global biological process model with a daily time step which simulates the water, energy and carbon budgets of plant growth. The primary product, the unique global gridded daily land temperature, and the precipitation data set which was used to drive the process model is described. The Biome-BGC model was tested by comparison with a simpler biological model driven by satellite-derived (NDVI) Normalized Difference Vegetation Index and (PAR) Photosynthetically Active Radiation data and by comparison with atmospheric CO2 observations. The simple NDVI model is also described. To facilitate the comparison with atmospheric CO2 observations, a three-dimensional atmospheric transport model was used to produce predictions of atmospheric CO2 variations given CO2 fluxes owing to (NPP) Net Primary Productivity and heterotrophic respiration that were produced by the Biome-BGC model and by the NDVI model. The transport model that we used in this project, and errors associated with transport simulations, were characterized by a comparison of 12 transport models.

  10. Twin Peaks - 3D

    NASA Technical Reports Server (NTRS)

    1997-01-01

    The two hills in the distance, approximately one to two kilometers away, have been dubbed the 'Twin Peaks' and are of great interest to Pathfinder scientists as objects of future study. 3D glasses are necessary to identify surface detail. The white areas on the left hill, called the 'Ski Run' by scientists, may have been formed by hydrologic processes.

    The IMP is a stereo imaging system with color capability provided by 24 selectable filters -- twelve filters per 'eye.

    Click below to see the left and right views individually. [figure removed for brevity, see original site] Left [figure removed for brevity, see original site] Right

  11. 3D and beyond

    NASA Astrophysics Data System (ADS)

    Fung, Y. C.

    1995-05-01

    This conference on physiology and function covers a wide range of subjects, including the vasculature and blood flow, the flow of gas, water, and blood in the lung, the neurological structure and function, the modeling, and the motion and mechanics of organs. Many technologies are discussed. I believe that the list would include a robotic photographer, to hold the optical equipment in a precisely controlled way to obtain the images for the user. Why are 3D images needed? They are to achieve certain objectives through measurements of some objects. For example, in order to improve performance in sports or beauty of a person, we measure the form, dimensions, appearance, and movements.

  12. 3D Audio System

    NASA Technical Reports Server (NTRS)

    1992-01-01

    Ames Research Center research into virtual reality led to the development of the Convolvotron, a high speed digital audio processing system that delivers three-dimensional sound over headphones. It consists of a two-card set designed for use with a personal computer. The Convolvotron's primary application is presentation of 3D audio signals over headphones. Four independent sound sources are filtered with large time-varying filters that compensate for motion. The perceived location of the sound remains constant. Possible applications are in air traffic control towers or airplane cockpits, hearing and perception research and virtual reality development.

  13. Global 3-d modeling of atmospheric ozone in the free troposphere and the stratosphere with emphasis on midlatitude regions. Final report, July 1, 1994--June 30, 1997

    SciTech Connect

    Brasseur, G.; Erickson, D.; Tie, X.; Walter, S.

    1997-12-01

    The objective of this research is to use global chemical-transport models to study the chemical and dynamical processes that affect midlatitude stratospheric ozone and to quantify the budget of tropospheric ozone. Four models will be improved and used: (1) a new version of the two-dimensional chemical-radiative-dynamical model with microphysical process of sulfate aerosols and polar stratospheric clouds (PSCs), and heterogeneous conversions on the surfaces of sulfate aerosols and PSCs; (2) the stratospheric version of three-dimensional off-line chemical-transport model (STARS) with a relatively high horizontal resolution (2.8 degree in latitudes) with a microphysical formation of PSCs; (3) the tropospheric version of three-dimensional off-line chemical-transport model (MOZART) with details in the surface emissions and hydrocarbon reactions to estimate the tropospheric ozone budget and perturbations; (4) the intermediate model of the global and annual evolution of species (IMAGES) with a detailed chemical reactions but relatively lower resolutions. Model results will be compared with available data.

  14. Estimates of mercury flux into the United States from non-local and global sources: results from a 3-D CTM simulation

    NASA Astrophysics Data System (ADS)

    Drewniak, B. A.; Kotamarthi, V. R.; Streets, D.; Kim, M.; Crist, K.

    2008-11-01

    The sensitivity of Hg concentration and deposition in the United States to emissions in China was investigated by using a global chemical transport model: Model for Ozone and Related Chemical Tracers (MOZART). Two forms of gaseous Hg were included in the model: elemental Hg (HG(0) and oxidized or reactive Hg (HGO). We simulated three different emission scenarios to evaluate the model's sensitivity. One scenario included no emissions from China, while the others were based on different estimates of Hg emissions in China. The results indicated, in general, that when Hg emissions were included, HG(0) concentrations increased both locally and globally. Increases in Hg concentrations in the United States were greatest during spring and summer, by as much as 7%. Ratios of calculated concentrations of Hg and CO near the source region in eastern Asia agreed well with ratios based on measurements. Increases similar to those observed for HG(0) were also calculated for deposition of HGO. Calculated increases in wet and dry deposition in the United States were 5 7% and 5 9%, respectively. The results indicate that long-range transcontinental transport of Hg has a non-negligible impact on Hg deposition levels in the United States.

  15. 3D Surgical Simulation

    PubMed Central

    Cevidanes, Lucia; Tucker, Scott; Styner, Martin; Kim, Hyungmin; Chapuis, Jonas; Reyes, Mauricio; Proffit, William; Turvey, Timothy; Jaskolka, Michael

    2009-01-01

    This paper discusses the development of methods for computer-aided jaw surgery. Computer-aided jaw surgery allows us to incorporate the high level of precision necessary for transferring virtual plans into the operating room. We also present a complete computer-aided surgery (CAS) system developed in close collaboration with surgeons. Surgery planning and simulation include construction of 3D surface models from Cone-beam CT (CBCT), dynamic cephalometry, semi-automatic mirroring, interactive cutting of bone and bony segment repositioning. A virtual setup can be used to manufacture positioning splints for intra-operative guidance. The system provides further intra-operative assistance with the help of a computer display showing jaw positions and 3D positioning guides updated in real-time during the surgical procedure. The CAS system aids in dealing with complex cases with benefits for the patient, with surgical practice, and for orthodontic finishing. Advanced software tools for diagnosis and treatment planning allow preparation of detailed operative plans, osteotomy repositioning, bone reconstructions, surgical resident training and assessing the difficulties of the surgical procedures prior to the surgery. CAS has the potential to make the elaboration of the surgical plan a more flexible process, increase the level of detail and accuracy of the plan, yield higher operative precision and control, and enhance documentation of cases. Supported by NIDCR DE017727, and DE018962 PMID:20816308

  16. Martian terrain - 3D

    NASA Technical Reports Server (NTRS)

    1997-01-01

    An area of rocky terrain near the landing site of the Sagan Memorial Station can be seen in this image, taken in stereo by the Imager for Mars Pathfinder (IMP) on Sol 3. 3D glasses are necessary to identify surface detail. This image is part of a 3D 'monster' panorama of the area surrounding the landing site.

    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.

    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

  17. Global 3-D modeling of atmospheric ozone in the free troposphere and the stratosphere with emphasis on midlatitude regions. Final report

    SciTech Connect

    Brasseur, G.; Tie, X.; Walters, S.

    1999-03-01

    The authors have used several global chemical/transport models (1) to study the contribution of various physical, chemical, and dynamical processes to the budget of mid-latitude ozone in the stratosphere and troposphere; (2) to analyze the potential mechanisms which are responsible for the observed ozone perturbations at mid-latitudes of the lower stratosphere and in the upper troposphere; (3) to calculate potential changes in atmospheric ozone response to anthropogenic changes (e.g., emission of industrially manufactured CFCs, CO, and NO{sub x}) and to natural perturbations (e.g., volcanic eruptions and biomass burning); and (4) to estimate the impact of these changes on the radiative forcing to the climate system and on the level of UV-B radiation at the surface.

  18. Positional Awareness Map 3D (PAM3D)

    NASA Technical Reports Server (NTRS)

    Hoffman, Monica; Allen, Earl L.; Yount, John W.; Norcross, April Louise

    2012-01-01

    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 3D.

  19. 3D field harmonics

    SciTech Connect

    Caspi, S.; Helm, M.; Laslett, L.J.

    1991-03-30

    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 3D 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.

  20. Hybrid [sigma]-p Coordinate Choices for a Global Model

    DTIC Science & Technology

    2009-01-01

    Arakawa–Lamb hybrid, which remains intrinsically less stable than the others. Impacts of different coordinates on forecast skill are neutral or...unclassified Standard Form 298 (Rev. 8-98) Prescribed by ANSI Std Z39-18 mons and Strüfing (1981) and Simmons and Burridge (1981) tested different ...0. This coordinate is defined by vertical profiles of the two coefficients, A and B, which control, respectively, its isobaric and terrain

  1. Investigating Global 3-D Shear-Wave Anisotropy in the Earth's Mantle from Free Oscillations, Body Waves, Surface Waves and Long-period Waveforms

    NASA Astrophysics Data System (ADS)

    Moulik, P.; Ekstrom, G.

    2012-12-01

    We have developed a framework that can be used to investigate anisotropic velocity, density and anelastic heterogeneity in the Earth's mantle using a wide spectrum (0.3-50 mHz) of seismological observables. We start with the extensive dataset of surface-wave phase anomalies, long-period waveforms, and body-wave travel times collected by Kustowski et al. (2008) for the development of the global model S362ANI. The additional data included in our analysis are splitting functions of spheroidal and toroidal modes, which are analogous to phase velocity maps at low frequencies. We include in this set of observations a new dataset containing the splitting functions of 56 spheroidal fundamental modes and overtones, measured by Deuss et al. (2011, 2012) using data from large recent earthquakes. Apart from providing unique constraints on the long-wavelength elastic and density structure in the mantle, the overtone splitting data are especially sensitive to the velocity (and anisotropic) structure in the transition zone and in the deeper mantle. The detection of anisotropy, a marker of flow, in the transition zone has implications for our understanding of mantle convection. Our forward modeling of the splitting functions, like the other types of data, includes the effects of radial anisotropy (Mochizuki, 1986). We show that the upper-mantle shear-wave anisotropy of S362ANI generates a clear contribution to the splitting functions of the modes that are sensitive to the upper-mantle structure. We explore the tradeoffs between fitting the mode splitting functions and the travel-times of body waves that turn in the transition zone or in the lower mantle (e.g. SS), while observing that the waveforms and the surface wave phase-anomalies provide complementary information about the mantle. Our experiments suggest that the splitting data are sufficiently sensitive to the anisotropy in the mantle such that their inclusion may provide a better depth resolution of the anisotropic shear

  2. Modeling cellular processes in 3D.

    PubMed

    Mogilner, Alex; Odde, David

    2011-12-01

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

  3. Intraoral 3D scanner

    NASA Astrophysics Data System (ADS)

    Kühmstedt, Peter; Bräuer-Burchardt, Christian; Munkelt, Christoph; Heinze, Matthias; Palme, Martin; Schmidt, Ingo; Hintersehr, Josef; Notni, Gunther

    2007-09-01

    Here a new set-up of a 3D-scanning system for CAD/CAM in dental industry is proposed. The system is designed for direct scanning of the dental preparations within the mouth. The measuring process is based on phase correlation technique in combination with fast fringe projection in a stereo arrangement. The novelty in the approach is characterized by the following features: A phase correlation between the phase values of the images of two cameras is used for the co-ordinate calculation. This works contrary to the usage of only phase values (phasogrammetry) or classical triangulation (phase values and camera image co-ordinate values) for the determination of the co-ordinates. The main advantage of the method is that the absolute value of the phase at each point does not directly determine the coordinate. Thus errors in the determination of the co-ordinates are prevented. Furthermore, using the epipolar geometry of the stereo-like arrangement the phase unwrapping problem of fringe analysis can be solved. The endoscope like measurement system contains one projection and two camera channels for illumination and observation of the object, respectively. The new system has a measurement field of nearly 25mm × 15mm. The user can measure two or three teeth at one time. So the system can by used for scanning of single tooth up to bridges preparations. In the paper the first realization of the intraoral scanner is described.

  4. 'Diamond' in 3-D

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This 3-D, 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.

    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.

    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.

    The image mosaic is about 6 centimeters (2.4 inches) across.

  5. Prominent rocks - 3D

    NASA Technical Reports Server (NTRS)

    1997-01-01

    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. 3D 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.

    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.

    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

  6. Ocean U.S. GODAE: Global Ocean Prediction with the HYbrid Coordinate Ocean Model (HYCOM)

    DTIC Science & Technology

    2008-10-01

    Ocean U.S. GODAE: Global Ocean Prediction with the HYbrid Coordinate Ocean Model (HYCOM) By Eric P. Chassignet1 and Harley E. Hurlburt2 1 COAPS ...UAcademia:U Florida State University/Center for Ocean-Atmospheric Prediction Studies ( COAPS ); University of Miami/Rosenstiel School of Marine and

  7. Global Hybrid HRSC+OMEGA Image Mosaics of Mars

    NASA Astrophysics Data System (ADS)

    McGuire, P. C.; Walter, S. H. G.; van Gasselt, S.; Dunke, A.; Dunker, T.; Gross, C.; Michael, G.; Wendt, L.; Audouard, J.; Ody, A.; Poulet, F.

    2014-04-01

    The High Resolution Stereo Camera (HRSC) on the Mars Express (MEx) orbiter has acquired 3640 images (with 'preliminary level 4' processing as described in [1]) of the Martian surface since arriving in orbit in 2003, covering over 90% of the planet [2]. At resolutions that can reach 10 meters/pixel, these MEx/HRSC images [3-4] are constructed in a pushbroom manner from 9 different CCD line sensors, including a panchromatic nadir-looking (Pan) channel, 4 color channels (R, G, B, IR), and 4 other panchromatic channels for stereo imaging or photometric imaging. In [5], we discussed our approach towards automatically mosaicking hundreds of the MEx/HRSC Pan or RGB images together. Herein, we present our latest results using this approach (Fig. 1; PDF is zoomable). Currently, our best results consist of adding a high-pass-filtered version of the HRSC mosaic to a low-pass-filtered version of the MEx/OMEGA [6] global mosaic.

  8. Hybrid ensemble 4DVar assimilation of stratospheric ozone using a global shallow water model

    NASA Astrophysics Data System (ADS)

    Allen, Douglas R.; Hoppel, Karl W.; Kuhl, David D.

    2016-07-01

    Wind extraction from stratospheric ozone (O3) assimilation is examined using a hybrid ensemble 4-D variational assimilation (4DVar) shallow water model (SWM) system coupled to the tracer advection equation. Stratospheric radiance observations are simulated using global observations of the SWM fluid height (Z), while O3 observations represent sampling by a typical polar-orbiting satellite. Four ensemble sizes were examined (25, 50, 100, and 1518 members), with the largest ensemble equal to the number of dynamical state variables. The optimal length scale for ensemble localization was found by tuning an ensemble Kalman filter (EnKF). This scale was then used for localizing the ensemble covariances that were blended with conventional covariances in the hybrid 4DVar experiments. Both optimal length scale and optimal blending coefficient increase with ensemble size, with optimal blending coefficients varying from 0.2-0.5 for small ensembles to 0.5-1.0 for large ensembles. The hybrid system outperforms conventional 4DVar for all ensemble sizes, while for large ensembles the hybrid produces similar results to the offline EnKF. Assimilating O3 in addition to Z benefits the winds in the hybrid system, with the fractional improvement in global vector wind increasing from ˜ 35 % with 25 and 50 members to ˜ 50 % with 1518 members. For the smallest ensembles (25 and 50 members), the hybrid 4DVar assimilation improves the zonal wind analysis over conventional 4DVar in the Northern Hemisphere (winter-like) region and also at the Equator, where Z observations alone have difficulty constraining winds due to lack of geostrophy. For larger ensembles (100 and 1518 members), the hybrid system results in both zonal and meridional wind error reductions, relative to 4DVar, across the globe.

  9. Hybrid Global Communication Architecture with Balloons and Satellites

    NASA Astrophysics Data System (ADS)

    Pignolet, G.; Celeste, A.; Erb, B.

    2002-01-01

    Global space communication systems have been developed now for more than three decades, based mainly on geostationary satellites or almost equivalent systems such as the Molnya orbit concepts. The last decade of the twentieth century has seen the emergence of satellite constellations in low or medium Earth orbit, in order to improve accessibility in terms of visibility at higher latitudes and limited size or power requirement for ground equipment. However such systems are complex to operate, there are still many situations where connection may remain difficult to achieve, and commercial benefits are still to be proven. A new concept, using a network combination of geostationary relay satellites and high altitude stratospheric platforms may well overcome the inconveniences of both geostationary systems and satellite constellations to improve greatly global communication in the future. The emergence of enabling technologies developed in Japan and in several other countries will soon make it possible to fly helium balloons in the upper layers of the atmosphere, at altitudes of 20 km or more. At such an altitude, well above the meteorological disturbances and the jet-streams, the stratosphere enjoys a regular wind at moderate speeds ranging between 10 m/s and 30 m/s, depending on latitude and also on season. It is possible for balloons powered by electric engines to fly non- stop upstream of the wind in order to remain stationary above a particular location. Large balloons, with sizes up to 300 m in length, would be able to carry sub-satellite communication payloads, as well as observation apparatus and scientific equipment. The range of visibility for easy both-way communication between the balloon and operators or customers on the ground could be as large as 200 km in radius. Most current studies consider a combination of solar cells and storage batteries to power the balloons, but microwave beam wireless power transportation from the ground could be a very

  10. M3D project for simulation studies of plasmas

    SciTech Connect

    Park, W.; Belova, E.V.; Fu, G.Y.; Strauss, H.R.; Sugiyama, L.E.

    1998-12-31

    The M3D (Multi-level 3D) project carries out simulation studies of plasmas of various regimes using multi-levels of physics, geometry, and mesh schemes in one code package. This paper and papers by Strauss, Sugiyama, and Belova in this workshop describe the project, and present examples of current applications. The currently available physics models of the M3D project are MHD, two-fluids, gyrokinetic hot particle/MHD hybrid, and gyrokinetic particle ion/two-fluid hybrid models. The code can be run with both structured and unstructured meshes.

  11. 3D Spectroscopy in Astronomy

    NASA Astrophysics Data System (ADS)

    Mediavilla, Evencio; Arribas, Santiago; Roth, Martin; Cepa-Nogué, Jordi; Sánchez, Francisco

    2011-09-01

    Preface; Acknowledgements; 1. Introductory review and technical approaches Martin M. Roth; 2. Observational procedures and data reduction James E. H. Turner; 3. 3D Spectroscopy instrumentation M. A. Bershady; 4. Analysis of 3D 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 3D spectroscopy data Sebastian F. Sánchez, Begona García-Lorenzo and Arlette Pécontal-Rousset.

  12. Spherical 3D isotropic wavelets

    NASA Astrophysics Data System (ADS)

    Lanusse, F.; Rassat, A.; Starck, J.-L.

    2012-04-01

    Context. Future cosmological surveys will provide 3D large scale structure maps with large sky coverage, for which a 3D spherical Fourier-Bessel (SFB) analysis in spherical coordinates is natural. Wavelets are particularly well-suited to the analysis and denoising of cosmological data, but a spherical 3D isotropic wavelet transform does not currently exist to analyse spherical 3D data. Aims: The aim of this paper is to present a new formalism for a spherical 3D isotropic wavelet, i.e. one based on the SFB decomposition of a 3D field and accompany the formalism with a public code to perform wavelet transforms. Methods: We describe a new 3D isotropic spherical wavelet decomposition based on the undecimated wavelet transform (UWT) described in Starck et al. (2006). We also present a new fast discrete spherical Fourier-Bessel transform (DSFBT) based on both a discrete Bessel transform and the HEALPIX angular pixelisation scheme. We test the 3D wavelet transform and as a toy-application, apply a denoising algorithm in wavelet space to the Virgo large box cosmological simulations and find we can successfully remove noise without much loss to the large scale structure. Results: We have described a new spherical 3D isotropic wavelet transform, ideally suited to analyse and denoise future 3D spherical cosmological surveys, which uses a novel DSFBT. We illustrate its potential use for denoising using a toy model. All the algorithms presented in this paper are available for download as a public code called MRS3D at http://jstarck.free.fr/mrs3d.html

  13. Parameterizing sorption isotherms using a hybrid global-local fitting procedure.

    PubMed

    Matott, L Shawn; Singh, Anshuman; Rabideau, Alan J

    2017-03-21

    Predictive modeling of the transport and remediation of groundwater contaminants requires an accurate description of the sorption process, which is usually provided by fitting an isotherm model to site-specific laboratory data. Commonly used calibration procedures, listed in order of increasing sophistication, include: trial-and-error, linearization, non-linear regression, global search, and hybrid global-local search. Given the considerable variability in fitting procedures applied in published isotherm studies, we investigated the importance of algorithm selection through a series of numerical experiments involving 13 previously published sorption datasets. These datasets, considered representative of state-of-the-art for isotherm experiments, had been previously analyzed using trial-and-error, linearization, or non-linear regression methods. The isotherm expressions were re-fit using a 3-stage hybrid global-local search procedure (i.e. global search using particle swarm optimization followed by Powell's derivative free local search method and Gauss-Marquardt-Levenberg non-linear regression). The re-fitted expressions were then compared to previously published fits in terms of the optimized weighted sum of squared residuals (WSSR) fitness function, the final estimated parameters, and the influence on contaminant transport predictions - where easily computed concentration-dependent contaminant retardation factors served as a surrogate measure of likely transport behavior. Results suggest that many of the previously published calibrated isotherm parameter sets were local minima. In some cases, the updated hybrid global-local search yielded order-of-magnitude reductions in the fitness function. In particular, of the candidate isotherms, the Polanyi-type models were most likely to benefit from the use of the hybrid fitting procedure. In some cases, improvements in fitness function were associated with slight (<10%) changes in parameter values, but in other cases

  14. 3D Elevation Program—Virtual USA in 3D

    USGS Publications Warehouse

    Lukas, Vicki; Stoker, J.M.

    2016-04-14

    The U.S. Geological Survey (USGS) 3D Elevation Program (3DEP) uses a laser system called ‘lidar’ (light detection and ranging) to create a virtual reality map of the Nation that is very accurate. 3D maps have many uses with new uses being discovered all the time.  

  15. A hybrid approach using chaotic dynamics and global search algorithms for combinatorial optimization problems

    NASA Astrophysics Data System (ADS)

    Igeta, Hideki; Hasegawa, Mikio

    Chaotic dynamics have been effectively applied to improve various heuristic algorithms for combinatorial optimization problems in many studies. Currently, the most used chaotic optimization scheme is to drive heuristic solution search algorithms applicable to large-scale problems by chaotic neurodynamics including the tabu effect of the tabu search. Alternatively, meta-heuristic algorithms are used for combinatorial optimization by combining a neighboring solution search algorithm, such as tabu, gradient, or other search method, with a global search algorithm, such as genetic algorithms (GA), ant colony optimization (ACO), or others. In these hybrid approaches, the ACO has effectively optimized the solution of many benchmark problems in the quadratic assignment problem library. In this paper, we propose a novel hybrid method that combines the effective chaotic search algorithm that has better performance than the tabu search and global search algorithms such as ACO and GA. Our results show that the proposed chaotic hybrid algorithm has better performance than the conventional chaotic search and conventional hybrid algorithms. In addition, we show that chaotic search algorithm combined with ACO has better performance than when combined with GA.

  16. 3D World Building System

    ScienceCinema

    None

    2016-07-12

    This video provides an overview of the Sandia National Laboratories developed 3-D World Model Building capability that provides users with an immersive, texture rich 3-D model of their environment in minutes using a laptop and color and depth camera.

  17. 3D Buckligami: Digital Matter

    NASA Astrophysics Data System (ADS)

    van Hecke, Martin; de Reus, Koen; Florijn, Bastiaan; Coulais, Corentin

    2014-03-01

    We present a class of elastic structures which exhibit collective buckling in 3D, and create these by a 3D printing/moulding technique. Our structures consist of cubic lattice of anisotropic unit cells, and we show that their mechanical properties are programmable via the orientation of these unit cells.

  18. 3D World Building System

    SciTech Connect

    2013-10-30

    This video provides an overview of the Sandia National Laboratories developed 3-D World Model Building capability that provides users with an immersive, texture rich 3-D model of their environment in minutes using a laptop and color and depth camera.

  19. Market study: 3-D eyetracker

    NASA Technical Reports Server (NTRS)

    1977-01-01

    A market study of a proposed version of a 3-D eyetracker for initial use at NASA's Ames Research Center was made. The commercialization potential of a simplified, less expensive 3-D 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.

  20. Euro3D Science Conference

    NASA Astrophysics Data System (ADS)

    Walsh, J. R.

    2004-02-01

    The Euro3D RTN is an EU funded Research Training Network to foster the exploitation of 3D spectroscopy in Europe. 3D spectroscopy is a general term for spectroscopy of an area of the sky and derives its name from its two spatial + one spectral dimensions. There are an increasing number of instruments which use integral field devices to achieve spectroscopy of an area of the sky, either using lens arrays, optical fibres or image slicers, to pack spectra of multiple pixels on the sky (``spaxels'') onto a 2D detector. On account of the large volume of data and the special methods required to reduce and analyse 3D data, there are only a few centres of expertise and these are mostly involved with instrument developments. There is a perceived lack of expertise in 3D spectroscopy spread though the astronomical community and its use in the armoury of the observational astronomer is viewed as being highly specialised. For precisely this reason the Euro3D RTN was proposed to train young researchers in this area and develop user tools to widen the experience with this particular type of data in Europe. The Euro3D RTN is coordinated by Martin M. Roth (Astrophysikalisches Institut Potsdam) and has been running since July 2002. The first Euro3D science conference was held in Cambridge, UK from 22 to 23 May 2003. The main emphasis of the conference was, in keeping with the RTN, to expose the work of the young post-docs who are funded by the RTN. In addition the team members from the eleven European institutes involved in Euro3D also presented instrumental and observational developments. The conference was organized by Andy Bunker and held at the Institute of Astronomy. There were over thirty participants and 26 talks covered the whole range of application of 3D techniques. The science ranged from Galactic planetary nebulae and globular clusters to kinematics of nearby galaxies out to objects at high redshift. Several talks were devoted to reporting recent observations with newly

  1. 3D vision system assessment

    NASA Astrophysics Data System (ADS)

    Pezzaniti, J. Larry; Edmondson, Richard; Vaden, Justin; Hyatt, Bryan; Chenault, David B.; Kingston, David; Geulen, Vanilynmae; Newell, Scott; Pettijohn, Brad

    2009-02-01

    In this paper, we report on the development of a 3D vision system consisting of a flat panel stereoscopic display and auto-converging stereo camera and an assessment of the system's use for robotic driving, manipulation, and surveillance operations. The 3D vision system was integrated onto a Talon Robot and Operator Control Unit (OCU) such that direct comparisons of the performance of a number of test subjects using 2D and 3D vision systems were possible. A number of representative scenarios were developed to determine which tasks benefited most from the added depth perception and to understand when the 3D vision system hindered understanding of the scene. Two tests were conducted at Fort Leonard Wood, MO with noncommissioned officers ranked Staff Sergeant and Sergeant First Class. The scenarios; the test planning, approach and protocols; the data analysis; and the resulting performance assessment of the 3D vision system are reported.

  2. 3D printing in dentistry.

    PubMed

    Dawood, A; Marti Marti, B; Sauret-Jackson, V; Darwood, A

    2015-12-01

    3D printing has been hailed as a disruptive technology which will change manufacturing. Used in aerospace, defence, art and design, 3D printing is becoming a subject of great interest in surgery. The technology has a particular resonance with dentistry, and with advances in 3D 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 3D 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 3D printing technologies available and their various applications in dentistry and in maxillofacial surgery.

  3. PLOT3D user's manual

    NASA Technical Reports Server (NTRS)

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

    1990-01-01

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

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

    NASA Technical Reports Server (NTRS)

    Buning, P.

    1994-01-01

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

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

    NASA Technical Reports Server (NTRS)

    Buning, P.

    1994-01-01

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

  6. Unassisted 3D camera calibration

    NASA Astrophysics Data System (ADS)

    Atanassov, Kalin; Ramachandra, Vikas; Nash, James; Goma, Sergio R.

    2012-03-01

    With the rapid growth of 3D technology, 3D image capture has become a critical part of the 3D feature set on mobile phones. 3D image quality is affected by the scene geometry as well as on-the-device processing. An automatic 3D system usually assumes known camera poses accomplished by factory calibration using a special chart. In real life settings, pose parameters estimated by factory calibration can be negatively impacted by movements of the lens barrel due to shaking, focusing, or camera drop. If any of these factors displaces the optical axes of either or both cameras, vertical disparity might exceed the maximum tolerable margin and the 3D user may experience eye strain or headaches. To make 3D capture more practical, one needs to consider unassisted (on arbitrary scenes) calibration. In this paper, we propose an algorithm that relies on detection and matching of keypoints between left and right images. Frames containing erroneous matches, along with frames with insufficiently rich keypoint constellations, are detected and discarded. Roll, pitch yaw , and scale differences between left and right frames are then estimated. The algorithm performance is evaluated in terms of the remaining vertical disparity as compared to the maximum tolerable vertical disparity.

  7. 3D Scan Systems Integration

    DTIC Science & Technology

    2007-11-02

    AGENCY USE ONLY (Leave Blank) 2. REPORT DATE 5 Feb 98 4. TITLE AND SUBTITLE 3D Scan Systems Integration REPORT TYPE AND DATES COVERED...2-89) Prescribed by ANSI Std. Z39-1 298-102 [ EDO QUALITY W3PECTEDI DLA-ARN Final Report for US Defense Logistics Agency on DDFG-T2/P3: 3D...SCAN SYSTEMS INTEGRATION Contract Number SPO100-95-D-1014 Contractor Ohio University Delivery Order # 0001 Delivery Order Title 3D Scan Systems

  8. A 3D Global Climate Model of the Pluto atmosphere coupled to a volatile transport model to interpret New Horizons observations, including the N2, CH4 and CO cycles and the formation of organic hazes

    NASA Astrophysics Data System (ADS)

    Bertrand, Tanguy; Forget, Francois

    2016-04-01

    To interpret New Horizons observations and simulate the Pluto climate system, we have developed a Global Climate Model (GCM) of Pluto's atmosphere. In addition to a 3D "dynamical core" which solves the equation of meteorology, the model takes into account the N2 condensation and sublimation and its thermal and dynamical effects, the vertical turbulent mixing, the radiative transfer through methane and carbon monoxide, molecular thermal conduction, and a detailed surface thermal model with different thermal inertia for various timescales (diurnal, seasonal). The GCM also includes a detailed model of the CH4 and CO cycles, taking into account their transport by the atmospheric circulation and turbulence, as well as their condensation and sublimation on the surface and in the atmosphere, possibly forming methane ice clouds. The GCM consistently predicts the 3D methane abundance in the atmosphere, which is used as an input for our radiative transfer calculation. In a second phase, we also developed a volatile transport model, derived from the GCM, which can be run over thousands of years in order to reach consistent initial states for the GCM runs and better explore the seasonal processes on Pluto. Results obtained with the volatile transport model show that the distribution of N2, CH4 and CO ices primarily depends on the seasonal thermal inertia used for the different ices, and is affected by the assumed topography as well. As observed, it is possible to form a large and permanent nitrogen glacier with CO and CH4 ice deposits in an equatorial basin corresponding to Sputnik Planum, while having a surface pressure evolution consistent with stellar occultations and New Horizons data. In addition, most of the methane ice is sequestered with N2 ice in the basin but seasonal polar caps of CH4 frosts also form explaining the bright polar caps observed with Hubble in the 1980s and in line with New Horizons observations. Using such balanced combination of surface and

  9. Reproducibility of 3D chromatin configuration reconstructions

    PubMed Central

    Segal, Mark R.; Xiong, Hao; Capurso, Daniel; Vazquez, Mariel; Arsuaga, Javier

    2014-01-01

    means for comparing 3D reconstruction solutions so that we can discern between local and global optima by contrasting solutions under perturbed inputs. PMID:24519450

  10. 3D polymer scaffold arrays.

    PubMed

    Simon, Carl G; Yang, Yanyin; Dorsey, Shauna M; Ramalingam, Murugan; Chatterjee, Kaushik

    2011-01-01

    We have developed a combinatorial platform for fabricating tissue scaffold arrays that can be used for screening cell-material interactions. Traditional research involves preparing samples one at a time for characterization and testing. Combinatorial and high-throughput (CHT) methods lower the cost of research by reducing the amount of time and material required for experiments by combining many samples into miniaturized specimens. In order to help accelerate biomaterials research, many new CHT methods have been developed for screening cell-material interactions where materials are presented to cells as a 2D film or surface. However, biomaterials are frequently used to fabricate 3D scaffolds, cells exist in vivo in a 3D environment and cells cultured in a 3D environment in vitro typically behave more physiologically than those cultured on a 2D surface. Thus, we have developed a platform for fabricating tissue scaffold libraries where biomaterials can be presented to cells in a 3D format.

  11. Autofocus for 3D imaging

    NASA Astrophysics Data System (ADS)

    Lee-Elkin, Forest

    2008-04-01

    Three dimensional (3D) autofocus remains a significant challenge for the development of practical 3D multipass radar imaging. The current 2D radar autofocus methods are not readily extendable across sensor passes. We propose a general framework that allows a class of data adaptive solutions for 3D auto-focus across passes with minimal constraints on the scene contents. The key enabling assumption is that portions of the scene are sparse in elevation which reduces the number of free variables and results in a system that is simultaneously solved for scatterer heights and autofocus parameters. The proposed method extends 2-pass interferometric synthetic aperture radar (IFSAR) methods to an arbitrary number of passes allowing the consideration of scattering from multiple height locations. A specific case from the proposed autofocus framework is solved and demonstrates autofocus and coherent multipass 3D estimation across the 8 passes of the "Gotcha Volumetric SAR Data Set" X-Band radar data.

  12. Combinatorial 3D Mechanical Metamaterials

    NASA Astrophysics Data System (ADS)

    Coulais, Corentin; Teomy, Eial; de Reus, Koen; Shokef, Yair; van Hecke, Martin

    2015-03-01

    We present a class of elastic structures which exhibit 3D-folding motion. Our structures consist of cubic lattices of anisotropic unit cells that can be tiled in a complex combinatorial fashion. We design and 3d-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.

  13. CASTOR3D: linear stability studies for 2D and 3D tokamak equilibria

    NASA Astrophysics Data System (ADS)

    Strumberger, E.; Günter, S.

    2017-01-01

    The CASTOR3D code, which is currently under development, is able to perform linear stability studies for 2D and 3D, ideal and resistive tokamak equilibria in the presence of ideal and resistive wall structures and coils. For these computations ideal equilibria represented by concentric nested flux surfaces serve as input (e.g. computed with the NEMEC code). Solving an extended eigenvalue problem, the CASTOR3D code takes simultaneously plasma inertia and wall resistivity into account. The code is a hybrid of the CASTOR_3DW stability code and the STARWALL code. The former is an extended version of the CASTOR and CASTOR_FLOW code, respectively. The latter is a linear 3D code computing the growth rates of resistive wall modes in the presence of multiply-connected wall structures. The CASTOR_3DW code, and some parts of the STARWALL code have been reformulated in a general 3D flux coordinate representation that allows to choose between various types of flux coordinates. Furthermore, the implemented many-valued current potentials in the STARWALL part allow a correct treatment of the m  =  0, n  =  0 perturbation. In this paper, we outline the theoretical concept, and present some numerical results which illustrate the present status of the code and demonstrate its numerous application possibilities.

  14. Hybrid particle swarm global optimization algorithm for phase diversity phase retrieval.

    PubMed

    Zhang, P G; Yang, C L; Xu, Z H; Cao, Z L; Mu, Q Q; Xuan, L

    2016-10-31

    The core problem of phase diversity phase retrieval (PDPR) is to find suitable optimization algorithms for wave-front sensing of different scales, especially for large-scale wavefront sensing. When dealing with large-scale wave-front sensing, existing gradient-based local optimization algorithms used in PDPR are easily trapped in local minimums near initial positions, and available global optimization algorithms possess low convergence efficiency. We construct a practicable optimization algorithm used in PDPR for large-scale wave-front sensing. This algorithm, named EPSO-BFGS, is a two-step hybrid global optimization algorithm based on the combination of evolutionary particle swarm optimization (EPSO) and the Broyden-Fletcher-Goldfarb-Shanno (BFGS) algorithm. Firstly, EPSO provides global search and obtains a rough global minimum position in limited search steps. Then, BFGS initialized by the rough global minimum position approaches the global minimum with high accuracy and fast convergence speed. Numerical examples testify to the feasibility and reliability of EPSO-BFGS for wave-front sensing of different scales. Two numerical cases also validate the ability of EPSO-BFGS for large-scale wave-front sensing. The effectiveness of EPSO-BFGS is further affirmed by performing a verification experiment.

  15. High-resolution 3D structural and optical analyses of hybrid or composite materials by means of scanning probe microscopy combined with the ultramicrotome technique: an example of application to engineering of liquid crystals doped with fluorescent quantum dots

    NASA Astrophysics Data System (ADS)

    Mochalov, Konstantin E.; Efimov, Anton E.; Bobrovsky, Alexey Yu.; Agapov, Igor I.; Chistyakov, Anton A.; Oleinikov, Vladimir A.; Nabiev, Igor

    2013-05-01

    Combination of nanometer-scale 3D structural analysis with optical characterization of the same material is a challenging task. Its results may be important for nanophotonics, materials science, and quality control. We have developed a new technique for complementary high-resolution structural and optical characterization followed by optical spectroscopic and microscopic measurements accompanied by reconstruction of the 3D structure in the same area of the sample. The 3D structure is reconstructed by combination of ultramicrotomic and SPM techniques allowing the study of the 3D distribution of implanted nanoparticles and their effect on the matrix structure. The combination of scanning probe nanotomography (SPN) and optical microspectroscopy makes it possible to direct estimate how the 3D structural characteristics of materials affect their macroscopic optical properties. The technique developed has been applied to the engineering of materials made from cholesteric liquid crystals and fluorescent quantum dots (QDs). These materials permit photochemical patterning and image recording through the changes in the dissymmetry factor of circular polarization of QD emission. The differences in the polarisation images and morphological characteristics of the liquid crystal matrix have proved to be correlated with the arrangement of the areas of homogeneous distribution and nonhomogeneous clustering of QDs. The reconstruction of the 3D structure of the liquid crystal matrix in the areas of homogeneous QD distribution has shown that QDs embedded into cholesteric liquid crystal matrices do not perturb their periodic planar texture. The combined optical/SPM/ultramicrotome technique will be indispensable for evaluating the effects of inorganic nanoparticles on the organisation of organic and liquid crystal matrices, biomedical materials, cells, and tissues.

  16. NASA Provides a 3-D Look at Typhoon Chaba

    NASA Video Gallery

    This 3-D flyby animation of Typhoon Chaba was created using data from NASA/JAXA's Global Precipitation Measurement mission or GPM core satellite. On Oct. 2, the GPM satellite saw some precipitation...

  17. A Game Theoretic Optimization Method for Energy Efficient Global Connectivity in Hybrid Wireless Sensor Networks

    PubMed Central

    Lee, JongHyup; Pak, Dohyun

    2016-01-01

    For practical deployment of wireless sensor networks (WSN), WSNs construct clusters, where a sensor node communicates with other nodes in its cluster, and a cluster head support connectivity between the sensor nodes and a sink node. In hybrid WSNs, cluster heads have cellular network interfaces for global connectivity. However, when WSNs are active and the load of cellular networks is high, the optimal assignment of cluster heads to base stations becomes critical. Therefore, in this paper, we propose a game theoretic model to find the optimal assignment of base stations for hybrid WSNs. Since the communication and energy cost is different according to cellular systems, we devise two game models for TDMA/FDMA and CDMA systems employing power prices to adapt to the varying efficiency of recent wireless technologies. The proposed model is defined on the assumptions of the ideal sensing field, but our evaluation shows that the proposed model is more adaptive and energy efficient than local selections. PMID:27589743

  18. A Game Theoretic Optimization Method for Energy Efficient Global Connectivity in Hybrid Wireless Sensor Networks.

    PubMed

    Lee, JongHyup; Pak, Dohyun

    2016-08-29

    For practical deployment of wireless sensor networks (WSN), WSNs construct clusters, where a sensor node communicates with other nodes in its cluster, and a cluster head support connectivity between the sensor nodes and a sink node. In hybrid WSNs, cluster heads have cellular network interfaces for global connectivity. However, when WSNs are active and the load of cellular networks is high, the optimal assignment of cluster heads to base stations becomes critical. Therefore, in this paper, we propose a game theoretic model to find the optimal assignment of base stations for hybrid WSNs. Since the communication and energy cost is different according to cellular systems, we devise two game models for TDMA/FDMA and CDMA systems employing power prices to adapt to the varying efficiency of recent wireless technologies. The proposed model is defined on the assumptions of the ideal sensing field, but our evaluation shows that the proposed model is more adaptive and energy efficient than local selections.

  19. From 3D view to 3D print

    NASA Astrophysics Data System (ADS)

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

    2014-08-01

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

  20. A Hybrid PSO-BFGS Strategy for Global Optimization of Multimodal Functions.

    PubMed

    Shutao Li; Mingkui Tan; Tsang, I W; Kwok, James Tin-Yau

    2011-08-01

    Particle swarm optimizer (PSO) is a powerful optimization algorithm that has been applied to a variety of problems. It can, however, suffer from premature convergence and slow convergence rate. Motivated by these two problems, a hybrid global optimization strategy combining PSOs with a modified Broyden-Fletcher-Goldfarb-Shanno (BFGS) method is presented in this paper. The modified BFGS method is integrated into the context of the PSOs to improve the particles' local search ability. In addition, in conjunction with the territory technique, a reposition technique to maintain the diversity of particles is proposed to improve the global search ability of PSOs. One advantage of the hybrid strategy is that it can effectively find multiple local solutions or global solutions to the multimodal functions in a box-constrained space. Based on these local solutions, a reconstruction technique can be adopted to further estimate better solutions. The proposed method is compared with several recently developed optimization algorithms on a set of 20 standard benchmark problems. Experimental results demonstrate that the proposed approach can obtain high-quality solutions on multimodal function optimization problems.

  1. YouDash3D: exploring stereoscopic 3D gaming for 3D movie theaters

    NASA Astrophysics Data System (ADS)

    Schild, Jonas; Seele, Sven; Masuch, Maic

    2012-03-01

    Along with the success of the digitally revived stereoscopic cinema, events beyond 3D movies become attractive for movie theater operators, i.e. interactive 3D games. In this paper, we present a case that explores possible challenges and solutions for interactive 3D 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 YouDash3D, a game prototype that explores public stereoscopic gameplay in a reduced kiosk setup. It features live 3D 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 3D movie theater gaming.

  2. Speaking Volumes About 3-D

    NASA Technical Reports Server (NTRS)

    2002-01-01

    In 1999, Genex submitted a proposal to Stennis Space Center for a volumetric 3-D display technique that would provide multiple users with a 360-degree perspective to simultaneously view and analyze 3-D 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 3-D display technology designed under an SBIR contract. The company Rainbow 3D(R) imaging camera is a novel, three-dimensional surface profile measurement system that can obtain a full-frame 3-D 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.

  3. 3D differential phase contrast microscopy

    PubMed Central

    Chen, Michael; Tian, Lei; Waller, Laura

    2016-01-01

    We demonstrate 3D phase and absorption recovery from partially coherent intensity images captured with a programmable LED array source. Images are captured through-focus with four different illumination patterns. Using first Born and weak object approximations (WOA), a linear 3D differential phase contrast (DPC) model is derived. The partially coherent transfer functions relate the sample’s complex refractive index distribution to intensity measurements at varying defocus. Volumetric reconstruction is achieved by a global FFT-based method, without an intermediate 2D phase retrieval step. Because the illumination is spatially partially coherent, the transverse resolution of the reconstructed field achieves twice the NA of coherent systems and improved axial resolution. PMID:27867705

  4. 3-D Force-balanced Magnetospheric Configurations

    SciTech Connect

    Sorin Zaharia; C.Z. Cheng; K. Maezawa

    2003-02-10

    The knowledge of plasma pressure is essential for many physics applications in the magnetosphere, such as computing magnetospheric currents and deriving magnetosphere-ionosphere coupling. A thorough knowledge of the 3-D pressure distribution has however eluded the community, as most in-situ pressure observations are either in the ionosphere or the equatorial region of the magnetosphere. With the assumption of pressure isotropy there have been attempts to obtain the pressure at different locations by either (a) mapping observed data (e.g., in the ionosphere) along the field lines of an empirical magnetospheric field model or (b) computing a pressure profile in the equatorial plane (in 2-D) or along the Sun-Earth axis (in 1-D) that is in force balance with the magnetic stresses of an empirical model. However, the pressure distributions obtained through these methods are not in force balance with the empirical magnetic field at all locations. In order to find a global 3-D plasma pressure distribution in force balance with the magnetospheric magnetic field, we have developed the MAG-3D code, that solves the 3-D force balance equation J x B = (upside-down delta) P computationally. Our calculation is performed in a flux coordinate system in which the magnetic field is expressed in terms of Euler potentials as B = (upside-down delta) psi x (upside-down delta) alpha. The pressure distribution, P = P(psi,alpha), is prescribed in the equatorial plane and is based on satellite measurements. In addition, computational boundary conditions for y surfaces are imposed using empirical field models. Our results provide 3-D distributions of magnetic field and plasma pressure as well as parallel and transverse currents for both quiet-time and disturbed magnetospheric conditions.

  5. Inferential modeling of 3D chromatin structure.

    PubMed

    Wang, Siyu; Xu, Jinbo; Zeng, Jianyang

    2015-04-30

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

  6. The EISCAT_3D Science Case

    NASA Astrophysics Data System (ADS)

    Tjulin, A.; Mann, I.; McCrea, I.; Aikio, A. T.

    2013-05-01

    EISCAT_3D will be a world-leading international research infrastructure using the incoherent scatter technique to study the atmosphere in the Fenno-Scandinavian Arctic and to investigate how the Earth's atmosphere is coupled to space. The EISCAT_3D phased-array multistatic radar system will be operated by EISCAT Scientific Association and thus be an integral part of an organisation that has successfully been running incoherent scatter radars for more than thirty years. The baseline design of the radar system contains a core site with transmitting and receiving capabilities located close to the intersection of the Swedish, Norwegian and Finnish borders and five receiving sites located within 50 to 250 km from the core. The EISCAT_3D project is currently in its Preparatory Phase and can smoothly transit into implementation in 2014, provided sufficient funding. Construction can start 2016 and first operations in 2018. The EISCAT_3D Science Case is prepared as part of the Preparatory Phase. It is regularly updated with annual new releases, and it aims at being a common document for the whole future EISCAT_3D user community. The areas covered by the Science Case are atmospheric physics and global change; space and plasma physics; solar system research; space weather and service applications; and radar techniques, new methods for coding and analysis. Two of the aims for EISCAT_3D are to understand the ways natural variability in the upper atmosphere, imposed by the Sun-Earth system, can influence the middle and lower atmosphere, and to improve the predictivity of atmospheric models by providing higher resolution observations to replace the current parametrised input. Observations by EISCAT_3D will also be used to monitor the direct effects from the Sun on the ionosphere-atmosphere system and those caused by solar wind magnetosphere-ionosphere interaction. In addition, EISCAT_3D will be used for remote sensing the large-scale behaviour of the magnetosphere from its

  7. 3D cartography of the Alpine Arc

    NASA Astrophysics Data System (ADS)

    Vouillamoz, N.; Sue, C.; Champagnac, J. D.; Calcagno, P.

    2012-04-01

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

  8. Macrophage podosomes go 3D.

    PubMed

    Van Goethem, Emeline; Guiet, Romain; Balor, Stéphanie; Charrière, Guillaume M; Poincloux, Renaud; Labrousse, Arnaud; Maridonneau-Parini, Isabelle; Le Cabec, Véronique

    2011-01-01

    Macrophage tissue infiltration is a critical step in the immune response against microorganisms and is also associated with disease progression in chronic inflammation and cancer. Macrophages are constitutively equipped with specialized structures called podosomes dedicated to extracellular matrix (ECM) degradation. We recently reported that these structures play a critical role in trans-matrix mesenchymal migration mode, a protease-dependent mechanism. Podosome molecular components and their ECM-degrading activity have been extensively studied in two dimensions (2D), but yet very little is known about their fate in three-dimensional (3D) environments. Therefore, localization of podosome markers and proteolytic activity were carefully examined in human macrophages performing mesenchymal migration. Using our gelled collagen I 3D matrix model to obligate human macrophages to perform mesenchymal migration, classical podosome markers including talin, paxillin, vinculin, gelsolin, cortactin were found to accumulate at the tip of F-actin-rich cell protrusions together with β1 integrin and CD44 but not β2 integrin. Macrophage proteolytic activity was observed at podosome-like protrusion sites using confocal fluorescence microscopy and electron microscopy. The formation of migration tunnels by macrophages inside the matrix was accomplished by degradation, engulfment and mechanic compaction of the matrix. In addition, videomicroscopy revealed that 3D F-actin-rich protrusions of migrating macrophages were as dynamic as their 2D counterparts. Overall, the specifications of 3D podosomes resembled those of 2D podosome rosettes rather than those of individual podosomes. This observation was further supported by the aspect of 3D podosomes in fibroblasts expressing Hck, a master regulator of podosome rosettes in macrophages. In conclusion, human macrophage podosomes go 3D and take the shape of spherical podosome rosettes when the cells perform mesenchymal migration. This work

  9. 3D Printed Bionic Nanodevices.

    PubMed

    Kong, Yong Lin; Gupta, Maneesh K; Johnson, Blake N; McAlpine, Michael C

    2016-06-01

    The ability to three-dimensionally interweave biological and functional materials could enable the creation of bionic devices possessing unique and compelling geometries, properties, and functionalities. Indeed, interfacing high performance active devices with biology could impact a variety of fields, including regenerative bioelectronic medicines, smart prosthetics, medical robotics, and human-machine interfaces. Biology, from the molecular scale of DNA and proteins, to the macroscopic scale of tissues and organs, is three-dimensional, often soft and stretchable, and temperature sensitive. This renders most biological platforms incompatible with the fabrication and materials processing methods that have been developed and optimized for functional electronics, which are typically planar, rigid and brittle. A number of strategies have been developed to overcome these dichotomies. One particularly novel approach is the use of extrusion-based multi-material 3D printing, which is an additive manufacturing technology that offers a freeform fabrication strategy. This approach addresses the dichotomies presented above by (1) using 3D printing and imaging for customized, hierarchical, and interwoven device architectures; (2) employing nanotechnology as an enabling route for introducing high performance materials, with the potential for exhibiting properties not found in the bulk; and (3) 3D printing a range of soft and nanoscale materials to enable the integration of a diverse palette of high quality functional nanomaterials with biology. Further, 3D printing is a multi-scale platform, allowing for the incorporation of functional nanoscale inks, the printing of microscale features, and ultimately the creation of macroscale devices. This blending of 3D printing, novel nanomaterial properties, and 'living' platforms may enable next-generation bionic systems. In this review, we highlight this synergistic integration of the unique properties of nanomaterials with the

  10. Petal, terrain & airbags - 3D

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Portions of the lander's deflated airbags and a petal are at the lower area of this image, taken in stereo by the Imager for Mars Pathfinder (IMP) on Sol 3. 3D glasses are necessary to identify surface detail. The metallic object at lower right is part of the lander's low-gain antenna. This image is part of a 3D 'monster

    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

  11. 3D Computations and Experiments

    SciTech Connect

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

    2004-04-05

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

  12. Met.3D - a new open-source tool for interactive 3D visualization of ensemble weather forecasts

    NASA Astrophysics Data System (ADS)

    Rautenhaus, Marc; Kern, Michael; Schäfler, Andreas; Westermann, Rüdiger

    2015-04-01

    We introduce Met.3D, a new open-source tool for the interactive 3D visualization of numerical ensemble weather predictions. The tool has been developed to support weather forecasting during aircraft-based atmospheric field campaigns, however, is applicable to further forecasting, research and teaching activities. Our work approaches challenging topics related to the visual analysis of numerical atmospheric model output -- 3D visualisation, ensemble visualization, and how both can be used in a meaningful way suited to weather forecasting. Met.3D builds a bridge from proven 2D visualization methods commonly used in meteorology to 3D visualization by combining both visualization types in a 3D context. It implements methods that address the issue of spatial perception in the 3D view as well as approaches to using the ensemble in order to assess forecast uncertainty. Interactivity is key to the Met.3D approach. The tool uses modern graphics hardware technology to achieve interactive visualization of present-day numerical weather prediction datasets on standard consumer hardware. Met.3D supports forecast data from the European Centre for Medium Range Weather Forecasts and operates directly on ECMWF hybrid sigma-pressure level grids. In this presentation, we provide an overview of the software --illustrated with short video examples--, and give information on its availability.

  13. Application of Hybrid Laminar Flow Control to Global Range Military Transport Aircraft

    NASA Technical Reports Server (NTRS)

    Lange, Roy H.

    1988-01-01

    A study was conducted to evaluate the application of hybrid laminar flow control (HLFC) to global range military transport aircraft. The global mission included the capability to transport 132,500 pounds of payload 6500 nautical miles, land and deliver the payload and without refueling return 6500 nautical miles to a friendly airbase. The preliminary design studies show significant performance benefits obtained for the HLFC aircraft as compared to counterpart turbulent flow aircraft. The study results at M=0.77 show that the largest benefits of HLFC are obtained with a high wing with engines on the wing configuration. As compared with the turbulent flow baseline aircraft, the high wing HLFC aircraft shows 17 percent reduction in fuel burned, 19.2 percent increase in lift-to-drag ratio, an insignificant increase in operating weight, and a 7.4 percent reduction in gross weight.

  14. The World of 3-D.

    ERIC Educational Resources Information Center

    Mayshark, Robin K.

    1991-01-01

    Students explore three-dimensional properties by creating red and green wall decorations related to Christmas. Students examine why images seem to vibrate when red and green pieces are small and close together. Instructions to conduct the activity and construct 3-D glasses are given. (MDH)

  15. 3D Printing: Exploring Capabilities

    ERIC Educational Resources Information Center

    Samuels, Kyle; Flowers, Jim

    2015-01-01

    As 3D 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…

  16. SNL3dFace

    SciTech Connect

    Russ, Trina; Koch, Mark; Koudelka, Melissa; Peters, Ralph; Little, Charles; Boehnen, Chris; Peters, Tanya

    2007-07-20

    This software distribution contains MATLAB and C++ code to enable identity verification using 3D 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 3D normalized face using Principal Component Analysis (PCA) and Fisher Linear Discriminant Analysis (FLDA). A 3D 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 3D environment.

  17. Making Inexpensive 3-D Models

    ERIC Educational Resources Information Center

    Manos, Harry

    2016-01-01

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

  18. 3D model retrieval method based on mesh segmentation

    NASA Astrophysics Data System (ADS)

    Gan, Yuanchao; Tang, Yan; Zhang, Qingchen

    2012-04-01

    In the process of feature description and extraction, current 3D model retrieval algorithms focus on the global features of 3D models but ignore the combination of global and local features of the model. For this reason, they show less effective performance to the models with similar global shape and different local shape. This paper proposes a novel algorithm for 3D model retrieval based on mesh segmentation. The key idea is to exact the structure feature and the local shape feature of 3D models, and then to compares the similarities of the two characteristics and the total similarity between the models. A system that realizes this approach was built and tested on a database of 200 objects and achieves expected results. The results show that the proposed algorithm improves the precision and the recall rate effectively.

  19. 3-D magnetic field calculations for wiggglers using MAGNUS-3D

    SciTech Connect

    Pissanetzky, S.; Tompkins, P.

    1988-01-01

    The recent but steady trend toward increased magnetic and geometric complexity in the design of wigglers and undulators, of which tapered wigglers, hybrid structures, laced electromagnetic wigglers, magnetic cladding, twisters and magic structures are examples, has caused a need for reliable 3-D computer models and a better understanding of the behavior of magnetic systems in three dimensions. The capabilities of the MAGNUS-3D Group of Programs are ideally suited to solve this class of problems and provide insight into 3-D effects. MAGNUS-3D can solve any problem of Magnetostatics involving permanent magnets, linear or nonlinear ferromagnetic materials and electric conductors of any shape in space. The magnetic properties of permanent magnets are described by the complete nonlinear demagnetization curve as provided by the manufacturer, or, at the user's choice, by a simpler approximation involving the coercive force, the residual induction and the direction of magnetization. The ferromagnetic materials are described by a magnetization table and an accurate interpolation relation. An internal library with properties of common industrial steels is available. The conductors are independent of the mesh and are described in terms of conductor elements from an internal library.

  20. TACO3D. 3-D Finite Element Heat Transfer Code

    SciTech Connect

    Mason, W.E.

    1992-03-04

    TACO3D 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. TACO3D 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. TACO3D 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.

  1. M3D-K Simulations of Beam-Driven Fishbone Instability in DIIID

    NASA Astrophysics Data System (ADS)

    Fu, Guoyong; Tobias, Benjamin; van Zeeland, Michael

    2013-10-01

    Fishbone instability is often observed between sawtooth crashes in DIII-D with sufficient on-axis neutral beam power. In this work, hybrid simulations with the global kinetic/MHD hybrid code M3D-K have been carried out to investigate the linear stability and nonlinear dynamics of n = 1 mode with effects of energetic beam ions for parameters and profiles of a DIII-D discharge. The results show that the n = 1 internal kink mode is unstable in MHD limit. However, with kinetic effects of beam ions, a fishbone-like mode is found to be unstable with mode frequency about a few kHz, consistent with experimental observation. Nonlinear simulations are being performed to investigate mode saturation, frequency chirping as well as energetic particle transport. Numerical results will be compared with the experimental data from DIII-D.

  2. Forensic 3D scene reconstruction

    NASA Astrophysics Data System (ADS)

    Little, Charles Q.; Small, Daniel E.; Peters, Ralph R.; Rigdon, J. B.

    2000-05-01

    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, 3D 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, 3D measurement and imaging system that would support law enforcement agents to quickly document and accurately record a crime scene.

  3. 3D Printed Robotic Hand

    NASA Technical Reports Server (NTRS)

    Pizarro, Yaritzmar Rosario; Schuler, Jason M.; Lippitt, Thomas C.

    2013-01-01

    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 3D 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 3D 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.

  4. Comparing swimsuits in 3D.

    PubMed

    van Geer, Erik; Molenbroek, Johan; Schreven, Sander; deVoogd-Claessen, Lenneke; Toussaint, Huib

    2012-01-01

    In competitive swimming, suits have become more important. These suits influence friction, pressure and wave drag. Friction drag is related to the surface properties whereas both pressure and wave drag are greatly influenced by body shape. To find a relationship between the body shape and the drag, the anthropometry of several world class female swimmers wearing different suits was accurately defined using a 3D scanner and traditional measuring methods. The 3D scans delivered more detailed information about the body shape. On the same day the swimmers did performance tests in the water with the tested suits. Afterwards the result of the performance tests and the differences found in body shape was analyzed to determine the deformation caused by a swimsuit and its effect on the swimming performance. Although the amount of data is limited because of the few test subjects, there is an indication that the deformation of the body influences the swimming performance.

  5. Forensic 3D Scene Reconstruction

    SciTech Connect

    LITTLE,CHARLES Q.; PETERS,RALPH R.; RIGDON,J. BRIAN; SMALL,DANIEL E.

    1999-10-12

    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, 3D 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, 3D measurement and imaging system that would support law enforcement agents to quickly document and accurately record a crime scene.

  6. Optical 3D imaging and visualization of concealed objects

    NASA Astrophysics Data System (ADS)

    Berginc, G.; Bellet, J.-B.; Berechet, I.; Berechet, S.

    2016-09-01

    This paper gives new insights on optical 3D imagery. In this paper we explore the advantages of laser imagery to form a three-dimensional image of the scene. 3D laser imaging can be used for three-dimensional medical imaging and surveillance because of ability to identify tumors or concealed objects. We consider the problem of 3D reconstruction based upon 2D angle-dependent laser images. The objective of this new 3D laser imaging is to provide users a complete 3D reconstruction of objects from available 2D data limited in number. The 2D laser data used in this paper come from simulations that are based on the calculation of the laser interactions with the different meshed objects of the scene of interest or from experimental 2D laser images. We show that combining the Radom transform on 2D laser images with the Maximum Intensity Projection can generate 3D views of the considered scene from which we can extract the 3D concealed object in real time. With different original numerical or experimental examples, we investigate the effects of the input contrasts. We show the robustness and the stability of the method. We have developed a new patented method of 3D laser imaging based on three-dimensional reflective tomographic reconstruction algorithms and an associated visualization method. In this paper we present the global 3D reconstruction and visualization procedures.

  7. [Real time 3D echocardiography

    NASA Technical Reports Server (NTRS)

    Bauer, F.; Shiota, T.; Thomas, J. D.

    2001-01-01

    Three-dimensional representation of the heart is an old concern. Usually, 3D 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 3D echocardiography is ready for clinical usage, some improvements are still necessary to improve its conviviality. Then real time 3D echocardiography could be the essential tool for understanding, diagnosis and management of patients.

  8. On the efficiency of the hybrid and the exact second-order sampling formulations of the EnKF: a reality-inspired 3-D test case for estimating biodegradation rates of chlorinated hydrocarbons at the port of Rotterdam

    NASA Astrophysics Data System (ADS)

    Gharamti, Mohamad E.; Valstar, Johan; Janssen, Gijs; Marsman, Annemieke; Hoteit, Ibrahim

    2016-11-01

    This study considers the assimilation problem of subsurface contaminants at the port of Rotterdam in the Netherlands. It involves the estimation of solute concentrations and biodegradation rates of four different chlorinated solvents. We focus on assessing the efficiency of an adaptive hybrid ensemble Kalman filter and optimal interpolation (EnKF-OI) and the exact second-order sampling formulation (EnKFESOS) for mitigating the undersampling of the estimation and observation errors covariances, respectively. A multi-dimensional and multi-species reactive transport model is coupled to simulate the migration of contaminants within a Pleistocene aquifer layer located around 25 m below mean sea level. The biodegradation chain of chlorinated hydrocarbons starting from tetrachloroethene and ending with vinyl chloride is modeled under anaerobic environmental conditions for 5 decades. Yearly pseudo-concentration data are used to condition the forecast concentration and degradation rates in the presence of model and observational errors. Assimilation results demonstrate the robustness of the hybrid EnKF-OI, for accurately calibrating the uncertain biodegradation rates. When implemented serially, the adaptive hybrid EnKF-OI scheme efficiently adjusts the weights of the involved covariances for each individual measurement. The EnKFESOS is shown to maintain the parameter ensemble spread much better leading to more robust estimates of the states and parameters. On average, a well tuned hybrid EnKF-OI and the EnKFESOS respectively suggest around 48 and 21 % improved concentration estimates, as well as around 70 and 23 % improved anaerobic degradation rates, over the standard EnKF. Incorporating large uncertainties in the flow model degrades the accuracy of the estimates of all schemes. Given that the performance of the hybrid EnKF-OI depends on the quality of the background statistics, satisfactory results were obtained only when the uncertainty imposed on the background

  9. GPU-Accelerated Denoising in 3D (GD3D)

    SciTech Connect

    2013-10-01

    The raw computational power GPU Accelerators enables fast denoising of 3D 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 the 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.

  10. An improved hybrid global optimization method for protein tertiary structure prediction

    PubMed Central

    McAllister, Scott R.

    2009-01-01

    First principles approaches to the protein structure prediction problem must search through an enormous conformational space to identify low-energy, near-native structures. In this paper, we describe the formulation of the tertiary structure prediction problem as a nonlinear constrained minimization problem, where the goal is to minimize the energy of a protein conformation subject to constraints on torsion angles and interatomic distances. The core of the proposed algorithm is a hybrid global optimization method that combines the benefits of the αBB deterministic global optimization approach with conformational space annealing. These global optimization techniques employ a local minimization strategy that combines torsion angle dynamics and rotamer optimization to identify and improve the selection of initial conformations and then applies a sequential quadratic programming approach to further minimize the energy of the protein conformations subject to constraints. The proposed algorithm demonstrates the ability to identify both lower energy protein structures, as well as larger ensembles of low-energy conformations. PMID:20357906

  11. The 3-D lattice theory of Flower Constellations

    NASA Astrophysics Data System (ADS)

    Davis, Jeremy J.; Avendaño, Martín E.; Mortari, Daniele

    2013-08-01

    Flower Constellations (FCs) have been extensively studied for use in optimal constellation design. The Harmonic FCs (HFCs) subset, representing the symmetric configurations, have recently been reformulated into 2-D Lattice Flower Constellations (2D-LFCs), encompassing the complete set of HFCs. Elliptic orbits are generally avoided due to the deleterious effects of Earth's oblateness on the constellation, but here we present a novel concept for avoiding this problem and enabling more effective global coverage utilizing elliptic orbits. This new 3D Lattice Flower Constellations (3D-LFCs) framework generalizes the 2D-LFCs, Walker constellations, elliptical Walker constellations, and many of Draim's global coverage constellations. Previous studies have shown FCs can provide improved performance in global navigation over existing Global Navigation Satellite Systems (GNSS). We found a 3D-LFC design that improved the average positioning accuracy by 3.5 % while reducing launch \\varDelta v requirements when compared to the existing Galileo GNSS constellation.

  12. Magmatic Systems in 3-D

    NASA Astrophysics Data System (ADS)

    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.

    2002-12-01

    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. 3-D 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 3-D datasets. These 3-D 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 3-D correlations between seafloor structure and seismic reflectivity. Exploration of 3-D 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

  13. 3D face recognition by projection-based methods

    NASA Astrophysics Data System (ADS)

    Dutagaci, Helin; Sankur, Bülent; Yemez, Yücel

    2006-02-01

    In this paper, we investigate recognition performances of various projection-based features applied on registered 3D scans of faces. Some features are data driven, such as ICA-based features or NNMF-based features. Other features are obtained using DFT or DCT-based schemes. We apply the feature extraction techniques to three different representations of registered faces, namely, 3D point clouds, 2D depth images and 3D voxel. We consider both global and local features. Global features are extracted from the whole face data, whereas local features are computed over the blocks partitioned from 2D depth images. The block-based local features are fused both at feature level and at decision level. The resulting feature vectors are matched using Linear Discriminant Analysis. Experiments using different combinations of representation types and feature vectors are conducted on the 3D-RMA dataset.

  14. From 1D chain to 3D network: a new family of inorganic-organic hybrid semiconductors MO3(L)(x) (M = Mo, W; L = organic linker) built on perovskite-like structure modules.

    PubMed

    Zhang, Xiao; Hejazi, Mehdi; Thiagarajan, Suraj J; Woerner, William R; Banerjee, Debasis; Emge, Thomas J; Xu, Wenqian; Teat, Simon J; Gong, Qihan; Safari, Ahmad; Yang, Ronggui; Parise, John B; Li, Jing

    2013-11-20

    MO3 (M = Mo, W) or VI-VI binary compounds are important semiconducting oxides that show great promise for a variety of applications. In an effort to tune and enhance their properties in a systematic manner we have applied a designing strategy to deliberately introduce organic linker molecules in these perovskite-like crystal lattices. This approach has led to a wealth of new hybrid structures built on one-dimensional (1D) and two-dimensional (2D) VI-VI modules. The hybrid semiconductors exhibit a number of greatly improved properties and new functionality, including broad band gap tunability, negative thermal expansion, largely reduced thermal conductivity, and significantly enhanced dielectric constant compared to their MO3 parent phases.

  15. Interactive 3D Mars Visualization

    NASA Technical Reports Server (NTRS)

    Powell, Mark W.

    2012-01-01

    The Interactive 3D 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 3D 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 3D 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.

  16. 3D Nanostructuring of Semiconductors

    NASA Astrophysics Data System (ADS)

    Blick, Robert

    2000-03-01

    Modern semiconductor technology allows to machine devices on the nanometer scale. I will discuss the current limits of the fabrication processes, which enable the definition of single electron transistors with dimensions down to 8 nm. In addition to the conventional 2D patterning and structuring of semiconductors, I will demonstrate how to apply 3D nanostructuring techniques to build freely suspended single-crystal beams with lateral dimension down to 20 nm. In transport measurements in the temperature range from 30 mK up to 100 K these nano-crystals are characterized regarding their electronic as well as their mechanical properties. Moreover, I will present possible applications of these devices.

  17. What Lies Ahead (3-D)

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This 3-D 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.

  18. Making Inexpensive 3-D Models

    NASA Astrophysics Data System (ADS)

    Manos, Harry

    2016-03-01

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

  19. A Clean Adirondack (3-D)

    NASA Technical Reports Server (NTRS)

    2004-01-01

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

  20. 3D Printed Shelby Cobra

    SciTech Connect

    Love, Lonnie

    2015-01-09

    ORNL's newly printed 3D Shelby Cobra was showcased at the 2015 NAIAS in Detroit. This "laboratory on wheels" uses the Shelby Cobra design, celebrating the 50th anniversary of this model and honoring the first vehicle to be voted a national monument. The Shelby was printed at the Department of Energy’s Manufacturing Demonstration Facility at ORNL using the BAAM (Big Area Additive Manufacturing) machine and is intended as a “plug-n-play” laboratory on wheels. The Shelby will allow research and development of integrated components to be tested and enhanced in real time, improving the use of sustainable, digital manufacturing solutions in the automotive industry.

  1. A hybrid SVM-FFA method for prediction of monthly mean global solar radiation

    NASA Astrophysics Data System (ADS)

    Shamshirband, Shahaboddin; Mohammadi, Kasra; Tong, Chong Wen; Zamani, Mazdak; Motamedi, Shervin; Ch, Sudheer

    2016-07-01

    In this study, a hybrid support vector machine-firefly optimization algorithm (SVM-FFA) model is proposed to estimate monthly mean horizontal global solar radiation (HGSR). The merit of SVM-FFA is assessed statistically by comparing its performance with three previously used approaches. Using each approach and long-term measured HGSR, three models are calibrated by considering different sets of meteorological parameters measured for Bandar Abbass situated in Iran. It is found that the model (3) utilizing the combination of relative sunshine duration, difference between maximum and minimum temperatures, relative humidity, water vapor pressure, average temperature, and extraterrestrial solar radiation shows superior performance based upon all approaches. Moreover, the extraterrestrial radiation is introduced as a significant parameter to accurately estimate the global solar radiation. The survey results reveal that the developed SVM-FFA approach is greatly capable to provide favorable predictions with significantly higher precision than other examined techniques. For the SVM-FFA (3), the statistical indicators of mean absolute percentage error (MAPE), root mean square error (RMSE), relative root mean square error (RRMSE), and coefficient of determination ( R 2) are 3.3252 %, 0.1859 kWh/m2, 3.7350 %, and 0.9737, respectively which according to the RRMSE has an excellent performance. As a more evaluation of SVM-FFA (3), the ratio of estimated to measured values is computed and found that 47 out of 48 months considered as testing data fall between 0.90 and 1.10. Also, by performing a further verification, it is concluded that SVM-FFA (3) offers absolute superiority over the empirical models using relatively similar input parameters. In a nutshell, the hybrid SVM-FFA approach would be considered highly efficient to estimate the HGSR.

  2. The PRISM3D paleoenvironmental reconstruction

    USGS Publications Warehouse

    Dowsett, H.; Robinson, M.; Haywood, A.M.; Salzmann, U.; Hill, Daniel; Sohl, L.E.; Chandler, M.; Williams, Mark; Foley, K.; Stoll, D.K.

    2010-01-01

    The Pliocene Research, Interpretation and Synoptic Mapping (PRISM) paleoenvironmental reconstruction is an internally consistent and comprehensive global synthesis of a past interval of relatively warm and stable climate. It is regularly used in model studies that aim to better understand Pliocene climate, to improve model performance in future climate scenarios, and to distinguish model-dependent climate effects. The PRISM reconstruction is constantly evolving in order to incorporate additional geographic sites and environmental parameters, and is continuously refined by independent research findings. The new PRISM three dimensional (3D) reconstruction differs from previous PRISM reconstructions in that it includes a subsurface ocean temperature reconstruction, integrates geochemical sea surface temperature proxies to supplement the faunal-based temperature estimates, and uses numerical models for the first time to augment fossil data. Here we describe the components of PRISM3D and describe new findings specific to the new reconstruction. Highlights of the new PRISM3D reconstruction include removal of Hudson Bay and the Great Lakes and creation of open waterways in locations where the current bedrock elevation is less than 25m above modern sea level, due to the removal of the West Antarctic Ice Sheet and the reduction of the East Antarctic Ice Sheet. The mid-Piacenzian oceans were characterized by a reduced east-west temperature gradient in the equatorial Pacific, but PRISM3D data do not imply permanent El Niño conditions. The reduced equator-to-pole temperature gradient that characterized previous PRISM reconstructions is supported by significant displacement of vegetation belts toward the poles, is extended into the Arctic Ocean, and is confirmed by multiple proxies in PRISM3D. Arctic warmth coupled with increased dryness suggests the formation of warm and salty paleo North Atlantic Deep Water (NADW) and a more vigorous thermohaline circulation system that may

  3. PSH3D fast Poisson solver for petascale DNS

    NASA Astrophysics Data System (ADS)

    Adams, Darren; Dodd, Michael; Ferrante, Antonino

    2016-11-01

    Direct numerical simulation (DNS) of high Reynolds number, Re >= O (105) , turbulent flows requires computational meshes >= O (1012) grid points, and, thus, the use of petascale supercomputers. DNS often requires the solution of a Helmholtz (or Poisson) equation for pressure, which constitutes the bottleneck of the solver. We have developed a parallel solver of the Helmholtz equation in 3D, PSH3D. The numerical method underlying PSH3D combines a parallel 2D Fast Fourier transform in two spatial directions, and a parallel linear solver in the third direction. For computational meshes up to 81923 grid points, our numerical results show that PSH3D scales up to at least 262k cores of Cray XT5 (Blue Waters). PSH3D has a peak performance 6 × faster than 3D FFT-based methods when used with the 'partial-global' optimization, and for a 81923 mesh solves the Poisson equation in 1 sec using 128k cores. Also, we have verified that the use of PSH3D with the 'partial-global' optimization in our DNS solver does not reduce the accuracy of the numerical solution of the incompressible Navier-Stokes equations.

  4. Investigation of surface wave amplitudes in 3-D velocity and 3-D Q models

    NASA Astrophysics Data System (ADS)

    Ruan, Y.; Zhou, Y.

    2010-12-01

    It has been long recognized that seismic amplitudes depend on both wave speed structures and anelasticity (Q) structures. However, the effects of lateral heterogeneities in wave speed and Q structures on seismic amplitudes has not been well understood. We investigate the effects of 3-D wave speed and 3-D anelasticity (Q) structures on surface-wave amplitudes based upon wave propagation simulations of twelve globally-distributed earthquakes and 801 stations in Earth models with and without lateral heterogeneities in wave speed and anelasticity using a Spectral Element Method (SEM). Our tomographic-like 3-D Q models are converted from a velocity model S20RTS using a set of reasonable mineralogical parameters, assuming lateral perturbations in both velocity and Q are due to temperature perturbations. Surface-wave amplitude variations of SEM seismograms are measured in the period range of 50--200 s using boxcar taper, cosine taper and Slepian multi-tapers. We calculate ray-theoretical predictions of surface-wave amplitude perturbations due to elastic focusing, attenuation, and anelastic focusing which respectively depend upon the second spatial derivative (''roughness'') of perturbations in phase velocity, 1/Q, and the roughness of perturbations in 1/Q. Both numerical experiments and theoretical calculations show that (1) for short-period (~ 50 s) surface waves, the effects of amplitude attenuation due to 3-D Q structures are comparable with elastic focusing effects due to 3-D wave speed structures; and (2) for long-period (> 100 s) surface waves, the effects of attenuation become much weaker than elastic focusing; and (3) elastic focusing effects are correlated with anelastic focusing at all periods due to the correlation between velocity and Q models; and (4) amplitude perturbations are depend on measurement techniques and therefore cannot be directly compared with ray-theoretical predictions because ray theory does not account for the effects of measurement

  5. Cloud Based Web 3d GIS Taiwan Platform

    NASA Astrophysics Data System (ADS)

    Tsai, W.-F.; Chang, J.-Y.; Yan, S. Y.; Chen, B.

    2011-09-01

    This article presents the status of the web 3D GIS platform, which has been developed in the National Applied Research Laboratories. The purpose is to develop a global earth observation 3D GIS platform for applications to disaster monitoring and assessment in Taiwan. For quick response to preliminary and detailed assessment after a natural disaster occurs, the web 3D GIS platform is useful to access, transfer, integrate, display and analyze the multi-scale huge data following the international OGC standard. The framework of cloud service for data warehousing management and efficiency enhancement using VMWare is illustrated in this article.

  6. 3D printed bionic ears.

    PubMed

    Mannoor, Manu S; Jiang, Ziwen; James, Teena; Kong, Yong Lin; Malatesta, Karen A; Soboyejo, Winston O; Verma, Naveen; Gracias, David H; McAlpine, Michael C

    2013-06-12

    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 3D 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 3D printing.

  7. 3D Printable Graphene Composite

    PubMed Central

    Wei, Xiaojun; Li, Dong; Jiang, Wei; Gu, Zheming; Wang, Xiaojuan; Zhang, Zengxing; Sun, Zhengzong

    2015-01-01

    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 (3D) 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 3D 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

  8. 3D Printed Bionic Ears

    PubMed Central

    Mannoor, Manu S.; Jiang, Ziwen; James, Teena; Kong, Yong Lin; Malatesta, Karen A.; Soboyejo, Winston O.; Verma, Naveen; Gracias, David H.; McAlpine, Michael C.

    2013-01-01

    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 3D 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 3D printing. PMID:23635097

  9. Martian terrain & airbags - 3D

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Portions of the lander's deflated airbags and a petal are at lower left in this image, taken in stereo by the Imager for Mars Pathfinder (IMP) on Sol 3. 3D glasses are necessary to identify surface detail. This image is part of a 3D 'monster' panorama of the area surrounding the landing site.

    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.

    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

  10. Martian terrain & airbags - 3D

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Portions of the lander's deflated airbags and a petal are at the lower area of this image, taken in stereo by the Imager for Mars Pathfinder (IMP) on Sol 3. 3D glasses are necessary to identify surface detail. This image is part of a 3D 'monster' panorama of the area surrounding the landing site.

    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.

    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

  11. 3D structured illumination microscopy

    NASA Astrophysics Data System (ADS)

    Dougherty, William M.; Goodwin, Paul C.

    2011-03-01

    Three-dimensional structured illumination microscopy achieves double the lateral and axial resolution of wide-field microscopy, using conventional fluorescent dyes, proteins and sample preparation techniques. A three-dimensional interference-fringe pattern excites the fluorescence, filling in the "missing cone" of the wide field optical transfer function, thereby enabling axial (z) discrimination. The pattern acts as a spatial carrier frequency that mixes with the higher spatial frequency components of the image, which usually succumb to the diffraction limit. The fluorescence image encodes the high frequency content as a down-mixed, moiré-like pattern. A series of images is required, wherein the 3D pattern is shifted and rotated, providing down-mixed data for a system of linear equations. Super-resolution is obtained by solving these equations. The speed with which the image series can be obtained can be a problem for the microscopy of living cells. Challenges include pattern-switching speeds, optical efficiency, wavefront quality and fringe contrast, fringe pitch optimization, and polarization issues. We will review some recent developments in 3D-SIM hardware with the goal of super-resolved z-stacks of motile cells.

  12. Volumetric medical image compression using 3D listless embedded block partitioning.

    PubMed

    Senapati, Ranjan K; Prasad, P M K; Swain, Gandharba; Shankar, T N

    2016-01-01

    This paper presents a listless variant of a modified three-dimensional (3D)-block coding algorithm suitable for medical image compression. A higher degree of correlation is achieved by using a 3D hybrid transform. The 3D hybrid transform is performed by a wavelet transform in the spatial dimension and a Karhunen-Loueve transform in the spectral dimension. The 3D transformed coefficients are arranged in a one-dimensional (1D) fashion, as in the hierarchical nature of the wavelet-coefficient distribution strategy. A novel listless block coding algorithm is applied to the mapped 1D coefficients which encode in an ordered-bit-plane fashion. The algorithm originates from the most significant bit plane and terminates at the least significant bit plane to generate an embedded bit stream, as in 3D-SPIHT. The proposed algorithm is called 3D hierarchical listless block (3D-HLCK), which exhibits better compression performance than that exhibited by 3D-SPIHT. Further, it is highly competitive with some of the state-of-the-art 3D wavelet coders for a wide range of bit rates for magnetic resonance, digital imaging and communication in medicine and angiogram images. 3D-HLCK provides rate and resolution scalability similar to those provided by 3D-SPIHT and 3D-SPECK. In addition, a significant memory reduction is achieved owing to the listless nature of 3D-HLCK.

  13. Peptide Directed 3D Assembly of Nanoparticles through Biomolecular Interaction

    NASA Astrophysics Data System (ADS)

    Kaur, Prerna

    The current challenge of the 'bottom up' process is the programmed self-assembly of nanoscale building blocks into complex and larger-scale superstructures with unique properties that can be integrated as components in solar cells, microelectronics, meta materials, catalysis, and sensors. Recent trends in the complexity of device design demand the fabrication of three-dimensional (3D) superstructures from multi-nanomaterial components in precise configurations. Bio mimetic assembly is an emerging technique for building hybrid materials because living organisms are efficient, inexpensive, and environmentally benign material generators, allowing low temperature fabrication. Using this approach, a novel peptide-directed nanomaterial assembly technology based on bio molecular interaction of streptavidin and biotin is presented for assembling nanomaterials with peptides for the construction of 3D peptide-inorganic superlattices with defined 3D shape. We took advantage of robust natural collagen triple-helix peptides and used them as nanowire building blocks for 3D peptide-gold nanoparticles superlattice generation. The type of 3D peptide superlattice assembly with hybrid NP building blocks described herein shows potential for the fabrication of complex functional device which demands precise long-range arrangement and periodicity of NPs.

  14. Total-Field Technique for 3-D Modeling of Short Period Teleseismic Waves

    NASA Astrophysics Data System (ADS)

    Monteiller, V.; Beller, S.; Operto, S.; Nissen-Meyer, T.; Tago Pacheco, J.; Virieux, J.

    2014-12-01

    The massive development of dense seismic arrays and the rapid increase in computing capacity allow today to consider application of full waveform inversion of teleseismic data for high-resolution lithospheric imaging. We present an hybrid numerical method that allows for the modellingof short period teleseismic waves in 3D lithospheric target with both the discontinuous Galerkin finite elements method and finite difference method, opening the possibility to perform waveform inversion of seismograms recorded by dense regional broadband arrays. However, despite the supercomputer ability, the forward-problem remains expensive at global scale for teleseismic configuration especially when 3D numerical methods are considered. In order to perform the forward problem in a reasonable amount of time, we reduce the computational domain in which full waveform modelling is performed. We define a 3D regional domain located below the seismological network that is embedded in a homogeneous background or axisymmetric model, in which the seismic wavefield can be computed efficiently. The background wavefield is used to compute the full wavefield in the 3D regional domain using the so-called total-field/scattered-field technique. This method relies on the decomposition of the wavefield into a background and a scattered wavefields. The computational domain is subdivided into three sub-domains: an outer domain formed by the perfectly-matched absorbing layers, an intermediate domain in which only the outgoing wavefield scattered by the lithospheric heterogeneities is computed, and the inner domain formed by the lithospheric target in which the full wavefield is computed. In this study, we shall present simulations in realistic lithospheric target when the axisymetric background wavefield is computed with the AxiSEM softwave and the 3D simulation in lithospheric target model is performed with the discontinuous Galerkin or finite difference method.

  15. 3D Printing of Graphene Aerogels.

    PubMed

    Zhang, Qiangqiang; Zhang, Feng; Medarametla, Sai Pradeep; Li, Hui; Zhou, Chi; Lin, Dong

    2016-04-06

    3D printing of a graphene aerogel with true 3D overhang structures is highlighted. The aerogel is fabricated by combining drop-on-demand 3D printing and freeze casting. The water-based GO ink is ejected and freeze-cast into designed 3D structures. The lightweight (<10 mg cm(-3) ) 3D printed graphene aerogel presents superelastic and high electrical conduction.

  16. Quasi 3D dispersion experiment

    NASA Astrophysics Data System (ADS)

    Bakucz, P.

    2003-04-01

    This paper studies the problem of tracer dispersion in a coloured fluid flowing through a two-phase 3D rough channel-system in a 40 cm*40 cm plexi-container filled by homogen glass fractions and colourless fluid. The unstable interface between the driving coloured fluid and the colourless fluid develops viscous fingers with a fractal structure at high capillary number. Five two-dimensional fractal fronts have been observed at the same time using four cameras along the vertical side-walls and using one camera located above the plexi-container. In possession of five fronts the spatial concentration contours are determined using statistical models. The concentration contours are self-affine fractal curves with a fractal dimension D=2.19. This result is valid for disperison at high Péclet numbers.

  17. ShowMe3D

    SciTech Connect

    Sinclair, Michael B

    2012-01-05

    ShowMe3D 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.

  18. 3D Printed Shelby Cobra

    ScienceCinema

    Love, Lonnie

    2016-11-02

    ORNL's newly printed 3D Shelby Cobra was showcased at the 2015 NAIAS in Detroit. This "laboratory on wheels" uses the Shelby Cobra design, celebrating the 50th anniversary of this model and honoring the first vehicle to be voted a national monument. The Shelby was printed at the Department of Energy’s Manufacturing Demonstration Facility at ORNL using the BAAM (Big Area Additive Manufacturing) machine and is intended as a “plug-n-play” laboratory on wheels. The Shelby will allow research and development of integrated components to be tested and enhanced in real time, improving the use of sustainable, digital manufacturing solutions in the automotive industry.

  19. Mechanisms of subantarctic mode water upwelling in a hybrid-coordinate global GCM

    NASA Astrophysics Data System (ADS)

    Zuo, Hao; Naveira Garabato, Alberto C.; New, Adrian L.; Oschlies, Andreas

    This article presents an investigation of the global circulation and upwelling of subantarctic mode water (SAMW), which is thought to be key in the supply of nutrients to support biological production over much of the world ocean excluding the North Pacific. The HYbrid isopycnic-cartesian Coordinate Ocean general circulation Model (HYCOM) is configured to simulate the global ocean circulation for time scales of up to centuries and a SAMW-tracking online tracer experiment is conducted. The tracer re-emergence fluxes across the mixed layer base effected by a range of physical mechanisms and by numerical mixing terms in HYCOM are diagnosed and discussed. For the global ocean north of 30°S, entrainment due to surface buoyancy loss and/or wind-induced mechanical stirring accounts for almost one third of the total tracer re-emergence. Ekman upwelling and shear-induced mixing are especially significant in the tropical oceans, and account for 19% and 18% of the total tracer re-emergence, respectively. There is substantial regional variation in the relative importance of the various upwelling mechanisms. Special attention is devoted to understanding the contrasting circulations of SAMW in the North Pacific and North Atlantic oceans. The modest penetration of SAMW into the North Pacific is found to arise from the comparatively light density level that the SAMW core resides at in the South Pacific Ocean, which results in its being captured by the Equatorial Undercurrent and prevents it from entering the western boundary current of the North Pacific. In the North Atlantic, a new conceptual model of SAMW circulation and re-emergence is proposed with application to nutrient supply to the regional upper ocean. The model formulates SAMW re-emergence as a sequence of distinct processes following the seasonal cycle of the thermocline as a water column circulates around the subtropical and subpolar gyres of the North Atlantic.

  20. 3D Tracking via Shoe Sensing

    PubMed Central

    Li, Fangmin; Liu, Guo; Liu, Jian; Chen, Xiaochuang; Ma, Xiaolin

    2016-01-01

    Most location-based services are based on a global positioning system (GPS), which only works well in outdoor environments. Compared to outdoor environments, indoor localization has created more buzz in recent years as people spent most of their time indoors working at offices and shopping at malls, etc. Existing solutions mainly rely on inertial sensors (i.e., accelerometer and gyroscope) embedded in mobile devices, which are usually not accurate enough to be useful due to the mobile devices’ random movements while people are walking. In this paper, we propose the use of shoe sensing (i.e., sensors attached to shoes) to achieve 3D indoor positioning. Specifically, a short-time energy-based approach is used to extract the gait pattern. Moreover, in order to improve the accuracy of vertical distance estimation while the person is climbing upstairs, a state classification is designed to distinguish the walking status including plane motion (i.e., normal walking and jogging horizontally), walking upstairs, and walking downstairs. Furthermore, we also provide a mechanism to reduce the vertical distance accumulation error. Experimental results show that we can achieve nearly 100% accuracy when extracting gait patterns from walking/jogging with a low-cost shoe sensor, and can also achieve 3D indoor real-time positioning with high accuracy. PMID:27801839

  1. 3D Model of Surfactant Replacement Therapy

    NASA Astrophysics Data System (ADS)

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

    2015-11-01

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

  2. Supernova Remnant in 3-D

    NASA Technical Reports Server (NTRS)

    2009-01-01

    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 3-D model using all of this information. A program called 3-D Slicer modified for astronomical use by the Astronomical Medicine Project at Harvard University in Cambridge, Mass. was used to display and manipulate the 3-D model. Commercial software was then used to create the 3-D fly-through.

    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.

    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 3-D 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.

    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

  3. Novel pyrimidine-2,4-dione-1,2,3-triazole and furo[2,3-d]pyrimidine-2-one-1,2,3-triazole hybrids as potential anti-cancer agents: Synthesis, computational and X-ray analysis and biological evaluation.

    PubMed

    Gregorić, Tomislav; Sedić, Mirela; Grbčić, Petra; Tomljenović Paravić, Andrea; Kraljević Pavelić, Sandra; Cetina, Mario; Vianello, Robert; Raić-Malić, Silvana

    2017-01-05

    Regioselective 1,4-disubstituted 1,2,3-triazole tethered pyrimidine-2,4-dione derivatives (5-23) were successfully prepared by the copper(I)-catalyzed click chemistry. While known palladium/copper-cocatalyzed method based on Sonogashira cross-coupling followed by the intramolecular 5-endo-dig ring closure generated novel 6-alkylfuro[2,3-d]pyrimidine-2-one-1,2,3-triazole hybrids (24b-37b), a small library of their 5-alkylethynyl analogs (24a-37a) was synthesized and described for the first time by tandem terminal alkyne dimerization and subsequent 5-endo-trig cyclization, which was additionally corroborated with computational and X-ray crystal structure analyses. The nature of substituents on alkynes and thereof homocoupled 1,3-diynes predominantly influenced the ratio of the formed products in both pathways. In vitro antiproliferative activity of prepared compounds evaluated on five human cancer cell lines revealed that N,N-1,3-bis-(1,2,3-triazole)-5-bromouracil (5-7) and 5,6-disubstituted furo[2,3-d]pyrimidine-2-one-1,2,3-triazole 34a hybrids exhibited the most pronounced cytostatic acitivities against hepatocellular carcinoma (HepG2) and cervical carcinoma (HeLa) cells with higher potencies than the reference drug 5-fluorouracil. Cytostatic effect of pyrimidine-2,4-dione-1,2,3-triazole hybrid 7 in HepG2 cells could be attributed to the Wee-1 kinase inhibition and abolishment of sphingolipid signaling mediated by acid ceramidase and sphingosine kinase 1. Importantly, this compound proved to be a non-mitochondrial toxicant, which makes it a promising candidate for further lead optimization and development of a new and more efficient agent for the treatment of hepatocellular carcinoma.

  4. Where Does the Density Localize? Convergent Behavior for Global Hybrids, Range Separation, and DFT+U.

    PubMed

    Gani, Terry Z H; Kulik, Heather J

    2016-12-13

    Approximate density functional theory (DFT) suffers from many-electron self-interaction error, otherwise known as delocalization error, that may be diagnosed and then corrected through elimination of the deviation from exact piecewise linear behavior between integer electron numbers. Although paths to correction of energetic delocalization error are well-established, the impact of these corrections on the electron density is less well-studied. Here, we compare the effect on density delocalization of DFT+U (i.e., semilocal DFT augmented with a Hubbard U correction), global hybrid tuning, and range-separated hybrid tuning on a diverse test set of 32 transition metal complexes and observe the three methods to have qualitatively equivalent effects on the ground state density. Regardless of valence orbital diffuseness (i.e., from 2p to 5p), ligand electronegativity (i.e., from Al to O), basis set (i.e., plane wave versus localized basis set), metal (i.e., Ti, Fe, Ni), and spin state, or tuning method, we consistently observe substantial charge loss at the metal and gain at ligand atoms (∼0.3-0.5 e or more). This charge loss at the metal is preferentially from the minority spin, leading to increasing magnetic moment as well. Using accurate wave function theory references, we observe that a minimum error in partial charges and magnetic moments occurs at higher tuning parameters than typically employed to eliminate energetic delocalization error. These observations motivate the need to develop multifaceted approximate-DFT error correction approaches that separately treat density delocalization and energetic errors to recover both correct density and orbital energy-derived properties.

  5. Gap Opening in 3D: Single-planet Gaps

    NASA Astrophysics Data System (ADS)

    Fung, Jeffrey; Chiang, Eugene

    2016-12-01

    Giant planets can clear deep gaps when embedded in 2D (razor-thin) viscous circumstellar disks. We show by direct simulation that giant planets are just as capable of carving out gaps in 3D. Surface density maps are similar between 2D and 3D, even in detail. In particular, the scaling {{{Σ }}}{gap}\\propto {q}-2 of gap surface density with planet mass, derived from a global “zero-dimensional” balance of Lindblad and viscous torques, applies equally well to results obtained at higher dimensions. Our 3D simulations reveal extensive, near-sonic, meridional flows both inside and outside the gaps; these large-scale circulations might bear on disk compositional gradients, in dust or other chemical species. At high planet mass, gap edges are mildly Rayleigh unstable and intermittently shed streams of material into the gap—less so in 3D than in 2D.

  6. 3D Kitaev spin liquids

    NASA Astrophysics Data System (ADS)

    Hermanns, Maria

    The Kitaev honeycomb model has become one of the archetypal spin models exhibiting topological phases of matter, where the magnetic moments fractionalize into Majorana fermions interacting with a Z2 gauge field. In this talk, we discuss generalizations of this model to three-dimensional lattice structures. Our main focus is the metallic state that the emergent Majorana fermions form. In particular, we discuss the relation of the nature of this Majorana metal to the details of the underlying lattice structure. Besides (almost) conventional metals with a Majorana Fermi surface, one also finds various realizations of Dirac semi-metals, where the gapless modes form Fermi lines or even Weyl nodes. We introduce a general classification of these gapless quantum spin liquids using projective symmetry analysis. Furthermore, we briefly outline why these Majorana metals in 3D Kitaev systems provide an even richer variety of Dirac and Weyl phases than possible for electronic matter and comment on possible experimental signatures. Work done in collaboration with Kevin O'Brien and Simon Trebst.

  7. 3D multiplexed immunoplasmonics microscopy

    NASA Astrophysics Data System (ADS)

    Bergeron, Éric; Patskovsky, Sergiy; Rioux, David; Meunier, Michel

    2016-07-01

    Selective labelling, identification and spatial distribution of cell surface biomarkers can provide important clinical information, such as distinction between healthy and diseased cells, evolution of a disease and selection of the optimal patient-specific treatment. Immunofluorescence is the gold standard for efficient detection of biomarkers expressed by cells. However, antibodies (Abs) conjugated to fluorescent dyes remain limited by their photobleaching, high sensitivity to the environment, low light intensity, and wide absorption and emission spectra. Immunoplasmonics is a novel microscopy method based on the visualization of Abs-functionalized plasmonic nanoparticles (fNPs) targeting cell surface biomarkers. Tunable fNPs should provide higher multiplexing capacity than immunofluorescence since NPs are photostable over time, strongly scatter light at their plasmon peak wavelengths and can be easily functionalized. In this article, we experimentally demonstrate accurate multiplexed detection based on the immunoplasmonics approach. First, we achieve the selective labelling of three targeted cell surface biomarkers (cluster of differentiation 44 (CD44), epidermal growth factor receptor (EGFR) and voltage-gated K+ channel subunit KV1.1) on human cancer CD44+ EGFR+ KV1.1+ MDA-MB-231 cells and reference CD44- EGFR- KV1.1+ 661W cells. The labelling efficiency with three stable specific immunoplasmonics labels (functionalized silver nanospheres (CD44-AgNSs), gold (Au) NSs (EGFR-AuNSs) and Au nanorods (KV1.1-AuNRs)) detected by reflected light microscopy (RLM) is similar to the one with immunofluorescence. Second, we introduce an improved method for 3D localization and spectral identification of fNPs based on fast z-scanning by RLM with three spectral filters corresponding to the plasmon peak wavelengths of the immunoplasmonics labels in the cellular environment (500 nm for 80 nm AgNSs, 580 nm for 100 nm AuNSs and 700 nm for 40 nm × 92 nm AuNRs). Third, the developed

  8. Crowdsourcing Based 3d Modeling

    NASA Astrophysics Data System (ADS)

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

    2016-06-01

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

  9. Designing 3D Multihierarchical Heteronanostructures for High-Performance On-Chip Hybrid Supercapacitors: Poly(3,4-(ethylenedioxy)thiophene)-Coated Diamond/Silicon Nanowire Electrodes in an Aprotic Ionic Liquid.

    PubMed

    Aradilla, David; Gao, Fang; Lewes-Malandrakis, Georgia; Müller-Sebert, Wolfgang; Gentile, Pascal; Boniface, Maxime; Aldakov, Dmitry; Iliev, Boyan; Schubert, Thomas J S; Nebel, Christoph E; Bidan, Gérard

    2016-07-20

    A versatile and robust hierarchically multifunctionalized nanostructured material made of poly(3,4-(ethylenedioxy)thiophene) (PEDOT)-coated diamond@silicon nanowires has been demonstrated to be an excellent capacitive electrode for supercapacitor devices. Thus, the electrochemical deposition of nanometric PEDOT films on diamond-coated silicon nanowire (SiNW) electrodes using N-methyl-N-propylpyrrolidinium bis((trifluoromethyl)sulfonyl)imide ionic liquid displayed a specific capacitance value of 140 F g(-1) at a scan rate of 1 mV s(-1). The as-grown functionalized electrodes were evaluated in a symmetric planar microsupercapacitor using butyltrimethylammonium bis((trifluoromethyl)sulfonyl)imide aprotic ionic liquid as the electrolyte. The device exhibited extraordinary energy and power density values of 26 mJ cm(-2) and 1.3 mW cm(-2) within a large voltage cell of 2.5 V, respectively. In addition, the system was able to retain 80% of its initial capacitance after 15 000 galvanostatic charge-discharge cycles at a high current density of 1 mA cm(-2) while maintaining a Coulombic efficiency around 100%. Therefore, this multifunctionalized hybrid device represents one of the best electrochemical performances concerning coated SiNW electrodes for a high-energy advanced on-chip supercapacitor.

  10. 3-D Hybrid Kinetic Modeling of the Interaction Between the Solar Wind and Lunar-like Exospheric Pickup Ions in Case of Oblique/ Quasi-Parallel/Parallel Upstream Magnetic Field

    NASA Technical Reports Server (NTRS)

    Lipatov, A. S.; Farrell, W. M.; Cooper, J. F.; Sittler, E. C., Jr.; Hartle, R. E.

    2015-01-01

    The interactions between the solar wind and Moon-sized objects are determined by a set of the solar wind parameters and plasma environment of the space objects. The orientation of upstream magnetic field is one of the key factors which determines the formation and structure of bow shock wave/Mach cone or Alfven wing near the obstacle. The study of effects of the direction of the upstream magnetic field on lunar-like plasma environment is the main subject of our investigation in this paper. Photoionization, electron-impact ionization and charge exchange are included in our hybrid model. The computational model includes the self-consistent dynamics of the light (hydrogen (+), helium (+)) and heavy (sodium (+)) pickup ions. The lunar interior is considered as a weakly conducting body. Our previous 2013 lunar work, as reported in this journal, found formation of a triple structure of the Mach cone near the Moon in the case of perpendicular upstream magnetic field. Further advances in modeling now reveal the presence of strong wave activity in the upstream solar wind and plasma wake in the cases of quasiparallel and parallel upstream magnetic fields. However, little wave activity is found for the opposite case with a perpendicular upstream magnetic field. The modeling does not show a formation of the Mach cone in the case of theta(Sub B,U) approximately equal to 0 degrees.

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

    NASA Astrophysics Data System (ADS)

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

    2016-06-01

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

  12. Hall effect control of magnetotail dawn-dusk asymmetry: A three-dimensional global hybrid simulation

    NASA Astrophysics Data System (ADS)

    Lu, San; Lin, Y.; Angelopoulos, V.; Artemyev, A. V.; Pritchett, P. L.; Lu, Quanming; Wang, X. Y.

    2016-12-01

    Magnetotail reconnection and related phenomena (e.g., flux ropes, dipolarizing flux bundles, flow bursts, and particle injections) occur more frequently on the duskside than on the dawnside. Because this asymmetry can directly result in dawn-dusk asymmetric space weather effects, uncovering its physical origin is important for better understanding, modeling, and prediction of the space weather phenomena. However, the cause of this pervasive asymmetry is unclear. Using three-dimensional global hybrid simulations, we demonstrate that the Hall physics in the magnetotail current sheet is responsible for the asymmetry. The current sheet thins progressively under enhanced global convection; when its thickness reaches ion kinetic scales, some ions are decoupled from the magnetized electrons (the Hall effect). The resultant Hall electric field Ez is directed toward the neutral plane. The Hall effect is stronger (grows faster) on the duskside; i.e., more ions become unmagnetized there and do not comove with the magnetized dawnward Ez × Bx drifting electrons, thus creating a larger additional cross-tail current intensity jy (in addition to the diamagnetic current) on the duskside, compared to the dawnside. The stronger Hall effect strength on the duskside is controlled by the higher ion temperature, thinner current sheet, and smaller normal magnetic field Bz there. These asymmetric current sheet properties are in turn controlled by two competing processes that correspond to the Hall effect: (1) the dawnward E × B drift of the magnetic flux and magnetized ions and electrons and (2) the transient motion of the unmagnetized ions which do not execute E × B drift.

  13. Filling gaps in cultural heritage documentation by 3D photography

    NASA Astrophysics Data System (ADS)

    Schuhr, W.; Lee, J. D.

    2015-08-01

    geometry" and to multistage concepts of 3D photographs in Cultural Heritage just started. Furthermore a revised list of the 3D visualization principles, claiming completeness, has been carried out. Beside others in an outlook *It is highly recommended, to list every historical and current stereo view with relevance to Cultural Heritage in a global Monument Information System (MIS), like in google earth. *3D photographs seem to be very suited, to complete and/or at least partly to replace manual archaeological sketches. In this concern the still underestimated 3D effect will be demonstrated, which even allows, e.g., the spatial perception of extremely small scratches etc... *A consequent dealing with 3D Technology even seems to indicate, currently we experience the beginning of a new age of "real 3DPC- screens", which at least could add or even partly replace the conventional 2D screens. Here the spatial visualization is verified without glasses in an all-around vitreous body. In this respect nowadays widespread lasered crystals showing monuments are identified as "Early Bird" 3D products, which, due to low resolution and contrast and due to lack of color, currently might even remember to the status of the invention of photography by Niepce (1827), but seem to promise a great future also in 3D Cultural Heritage documentation. *Last not least 3D printers more and more seem to conquer the IT-market, obviously showing an international competition.

  14. Expected Characteristics of Global Wind Profile Measurements with a Scanning, Hybrid, Doppler Lidar System

    NASA Technical Reports Server (NTRS)

    Kavaya, Michael J.

    2008-01-01

    Over 20 years of investigation by NASA and NOAA scientists and Doppler lidar technologists into a global wind profiling mission from earth orbit have led to the current favored concept of an instrument with both coherent- and direct-detection pulsed Doppler lidars (i.e., a hybrid Doppler lidar) and a stepstare beam scanning approach covering several azimuth angles with a fixed nadir angle. The nominal lidar wavelengths are 2 microns for coherent detection, and 0.355 microns for direct detection. The two agencies have also generated two sets of sophisticated wind measurement requirements for a space mission: science demonstration requirements and operational requirements. The requirements contain the necessary details to permit mission design and optimization by lidar technologists. Simulations have been developed that connect the science requirements to the wind measurement requirements, and that connect the wind measurement requirements to the Doppler lidar parameters. The simulations also permit trade studies within the multi-parameter space. These tools, combined with knowledge of the state of the Doppler lidar technology, have been used to conduct space instrument and mission design activities to validate the feasibility of the chosen mission and lidar parameters. Recently, the NRC Earth Science Decadal Survey recommended the wind mission to NASA as one of 15 recommended missions. A full description of the wind measurement product from these notional missions and the possible trades available are presented in this paper.

  15. A hybrid cuckoo search algorithm with Nelder Mead method for solving global optimization problems.

    PubMed

    Ali, Ahmed F; Tawhid, Mohamed A

    2016-01-01

    Cuckoo search algorithm is a promising metaheuristic population based method. It has been applied to solve many real life problems. In this paper, we propose a new cuckoo search algorithm by combining the cuckoo search algorithm with the Nelder-Mead method in order to solve the integer and minimax optimization problems. We call the proposed algorithm by hybrid cuckoo search and Nelder-Mead method (HCSNM). HCSNM starts the search by applying the standard cuckoo search for number of iterations then the best obtained solution is passing to the Nelder-Mead algorithm as an intensification process in order to accelerate the search and overcome the slow convergence of the standard cuckoo search algorithm. The proposed algorithm is balancing between the global exploration of the Cuckoo search algorithm and the deep exploitation of the Nelder-Mead method. We test HCSNM algorithm on seven integer programming problems and ten minimax problems and compare against eight algorithms for solving integer programming problems and seven algorithms for solving minimax problems. The experiments results show the efficiency of the proposed algorithm and its ability to solve integer and minimax optimization problems in reasonable time.

  16. [3D emulation of epicardium dynamic mapping].

    PubMed

    Lu, Jun; Yang, Cui-Wei; Fang, Zu-Xiang

    2005-03-01

    In order to realize epicardium dynamic mapping of the whole atria, 3-D graphics are drawn with OpenGL. Some source codes are introduced in the paper to explain how to produce, read, and manipulate 3-D model data.

  17. An interactive multiview 3D display system

    NASA Astrophysics Data System (ADS)

    Zhang, Zhaoxing; Geng, Zheng; Zhang, Mei; Dong, Hui

    2013-03-01

    The progresses in 3D display systems and user interaction technologies will help more effective 3D visualization of 3D information. They yield a realistic representation of 3D objects and simplifies our understanding to the complexity of 3D objects and spatial relationship among them. In this paper, we describe an autostereoscopic multiview 3D display system with capability of real-time user interaction. Design principle of this autostereoscopic multiview 3D display system is presented, together with the details of its hardware/software architecture. A prototype is built and tested based upon multi-projectors and horizontal optical anisotropic display structure. Experimental results illustrate the effectiveness of this novel 3D display and user interaction system.

  18. 3-D Electromagnetic Instabilities in Current Sheet

    NASA Astrophysics Data System (ADS)

    Wang, Zhenyu; Lin, Yu; Wang, Xueyi; Chen, Liu; Tummel, Kurt

    2016-10-01

    3-D electromagnetic instabilities in a Harris current sheet with a finite guide magnetic field BG are systematically studied by employing the gyrokinetic electron and fully kinetic ion (GeFi) particle model with a realistic mass ratio mi /me . Our studies show that lower-hybrid drift instability (LHDI) with k√{ρiρe } 1 and drift kink instability (DKI) and drift sausage instability (DSI) with kρi 1 are excited in the current sheet. The most unstable DKI is away from k . B = 0 , and the most unstable DSI is at k . B = 0 , where k ≡ (kx ,ky) , with kx being along the anti-parallel field direction and ky is along the current direction. On the other hand, an instability with a compressional magnetic field perturbation located at the center of current sheet is also excited under a relatively large BG, and its maximum growth rate is at k × B = 0 . The presence and structure of these instabilities as a function of BG is presented. The GeFi simulation results are compared with those from the fully kinetic particle simulation.

  19. Laser Based 3D Volumetric Display System

    DTIC Science & Technology

    1993-03-01

    Literature, Costa Mesa, CA July 1983. 3. "A Real Time Autostereoscopic Multiplanar 3D Display System", Rodney Don Williams, Felix Garcia, Jr., Texas...8217 .- NUMBERS LASER BASED 3D VOLUMETRIC DISPLAY SYSTEM PR: CD13 0. AUTHOR(S) PE: N/AWIU: DN303151 P. Soltan, J. Trias, W. Robinson, W. Dahlke 7...laser generated 3D volumetric images on a rotating double helix, (where the 3D displays are computer controlled for group viewing with the naked eye

  20. True 3d Images and Their Applications

    NASA Astrophysics Data System (ADS)

    Wang, Z.; wang@hzgeospace., zheng.

    2012-07-01

    A true 3D image is a geo-referenced image. Besides having its radiometric information, it also has true 3Dground coordinates XYZ for every pixels of it. For a true 3D image, especially a true 3D oblique image, it has true 3D coordinates not only for building roofs and/or open grounds, but also for all other visible objects on the ground, such as visible building walls/windows and even trees. The true 3D image breaks the 2D barrier of the traditional orthophotos by introducing the third dimension (elevation) into the image. From a true 3D image, for example, people will not only be able to read a building's location (XY), but also its height (Z). true 3D images will fundamentally change, if not revolutionize, the way people display, look, extract, use, and represent the geospatial information from imagery. In many areas, true 3D images can make profound impacts on the ways of how geospatial information is represented, how true 3D ground modeling is performed, and how the real world scenes are presented. This paper first gives a definition and description of a true 3D image and followed by a brief review of what key advancements of geospatial technologies have made the creation of true 3D images possible. Next, the paper introduces what a true 3D image is made of. Then, the paper discusses some possible contributions and impacts the true 3D images can make to geospatial information fields. At the end, the paper presents a list of the benefits of having and using true 3D images and the applications of true 3D images in a couple of 3D city modeling projects.

  1. 3-D Experimental Fracture Analysis at High Temperature

    SciTech Connect

    John H. Jackson; Albert S. Kobayashi

    2001-09-14

    T*e, which is an elastic-plastic fracture parameter based on incremental theory of plasticity, was determined numerically and experimentally. The T*e integral of a tunneling crack in 2024-T3 aluminum, three point bend specimen was obtained through a hybrid analysis of moire interferometry and 3-D elastic-plastic finite element analysis. The results were verified by the good agreement between the experimentally and numerically determined T*e on the specimen surface.

  2. Automated modeling of RNA 3D structure.

    PubMed

    Rother, Kristian; Rother, Magdalena; Skiba, Pawel; Bujnicki, Janusz M

    2014-01-01

    This chapter gives an overview over the current methods for automated modeling of RNA structures, with emphasis on template-based methods. The currently used approaches to RNA modeling are presented with a side view on the protein world, where many similar ideas have been used. Two main programs for automated template-based modeling are presented: ModeRNA assembling structures from fragments and MacroMoleculeBuilder performing a simulation to satisfy spatial restraints. Both approaches have in common that they require an alignment of the target sequence to a known RNA structure that is used as a modeling template. As a way to find promising template structures and to align the target and template sequences, we propose a pipeline combining the ParAlign and Infernal programs on RNA family data from Rfam. We also briefly summarize template-free methods for RNA 3D structure prediction. Typically, RNA structures generated by automated modeling methods require local or global optimization. Thus, we also discuss methods that can be used for local or global refinement of RNA structures.

  3. Evolution of flux ropes in the magnetotail: A three-dimensional global hybrid simulation

    SciTech Connect

    Lu, S.; Lin, Y.; Wang, X. Y.; Lu, Q. M. Huang, C.; Wu, M. Y.; Wang, S.; Wang, R. S.

    2015-05-15

    Flux ropes in the Earth's magnetotail are widely believed to play a crucial role in energy transport during substorms and the generation of energetic particles. Previous kinetic simulations are limited to the local-scale regime, and thus cannot be used to study the structure associated with the geomagnetic field and the global-scale evolution of the flux ropes. Here, the evolution of flux ropes in the magnetotail under a steady southward interplanetary magnetic field are studied with a newly developed three-dimensional global hybrid simulation model for dynamics ranging from the ion Larmor radius to the global convection time scales. Magnetic reconnection with multiple X-lines is found to take place in the near-tail current sheet at geocentric solar magnetospheric distances x=−30R{sub E}∼−15R{sub E} around the equatorial plane (z=0). The magnetotail reconnection layer is turbulent, with a nonuniform structure and unsteady evolution, and exhibits properties of typical collisionless fast reconnection with the Hall effect. A number of small-scale flux ropes are generated through the multiple X-line reconnection. The diameter of the flux ropes is several R{sub E}, and the spatial scale of the flux ropes in the dawn-dusk direction is on the order of several R{sub E} and does not extend across the entire section of the magnetotail, contrary to previous models and MHD simulation results and showing the importance of the three-dimensional effects. The nonuniform and unsteady multiple X-line reconnection with particle kinetic effects leads to various kinds of flux rope evolution: The small-scale flux ropes propagate earthward or tailward after formation, and eventually merge into the near-Earth region or the mid-/distant-tail plasmoid, respectively. During the propagation, some of the flux ropes can be tilted in the geocentric solar magnetospheric (x,y) plane with respect to the y (dawn-dusk) axis. Coalescence between flux ropes is also observed. At the same time, the

  4. 3D Printing and Its Urologic Applications

    PubMed Central

    Soliman, Youssef; Feibus, Allison H; Baum, Neil

    2015-01-01

    3D printing is the development of 3D objects via an additive process in which successive layers of material are applied under computer control. This article discusses 3D printing, with an emphasis on its historical context and its potential use in the field of urology. PMID:26028997

  5. Teaching Geography with 3-D Visualization Technology

    ERIC Educational Resources Information Center

    Anthamatten, Peter; Ziegler, Susy S.

    2006-01-01

    Technology that helps students view images in three dimensions (3-D) can support a broad range of learning styles. "Geo-Wall systems" are visualization tools that allow scientists, teachers, and students to project stereographic images and view them in 3-D. We developed and presented 3-D visualization exercises in several undergraduate courses.…

  6. Expanding Geometry Understanding with 3D Printing

    ERIC Educational Resources Information Center

    Cochran, Jill A.; Cochran, Zane; Laney, Kendra; Dean, Mandi

    2016-01-01

    With the rise of personal desktop 3D printing, a wide spectrum of educational opportunities has become available for educators to leverage this technology in their classrooms. Until recently, the ability to create physical 3D models was well beyond the scope, skill, and budget of many schools. However, since desktop 3D printers have become readily…

  7. Beowulf 3D: a case study

    NASA Astrophysics Data System (ADS)

    Engle, Rob

    2008-02-01

    This paper discusses the creative and technical challenges encountered during the production of "Beowulf 3D," director Robert Zemeckis' adaptation of the Old English epic poem and the first film to be simultaneously released in IMAX 3D and digital 3D formats.

  8. 3D Flow Visualization Using Texture Advection

    NASA Technical Reports Server (NTRS)

    Kao, David; Zhang, Bing; Kim, Kwansik; Pang, Alex; Moran, Pat (Technical Monitor)

    2001-01-01

    Texture advection is an effective tool for animating and investigating 2D flows. In this paper, we discuss how this technique can be extended to 3D flows. In particular, we examine the use of 3D and 4D textures on 3D synthetic and computational fluid dynamics flow fields.

  9. Integration of real-time 3D capture, reconstruction, and light-field display

    NASA Astrophysics Data System (ADS)

    Zhang, Zhaoxing; Geng, Zheng; Li, Tuotuo; Pei, Renjing; Liu, Yongchun; Zhang, Xiao

    2015-03-01

    Effective integration of 3D acquisition, reconstruction (modeling) and display technologies into a seamless systems provides augmented experience of visualizing and analyzing real objects and scenes with realistic 3D sensation. Applications can be found in medical imaging, gaming, virtual or augmented reality and hybrid simulations. Although 3D acquisition, reconstruction, and display technologies have gained significant momentum in recent years, there seems a lack of attention on synergistically combining these components into a "end-to-end" 3D visualization system. We designed, built and tested an integrated 3D visualization system that is able to capture in real-time 3D light-field images, perform 3D reconstruction to build 3D model of the objects, and display the 3D model on a large autostereoscopic screen. In this article, we will present our system architecture and component designs, hardware/software implementations, and experimental results. We will elaborate on our recent progress on sparse camera array light-field 3D acquisition, real-time dense 3D reconstruction, and autostereoscopic multi-view 3D display. A prototype is finally presented with test results to illustrate the effectiveness of our proposed integrated 3D visualization system.

  10. 3-D Perspective Pasadena, California

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This perspective view shows the western part of the city of Pasadena, California, looking north towards the San Gabriel Mountains. Portions of the cities of Altadena and La Canada, Flintridge are also shown. The image was created from three datasets: the Shuttle Radar Topography Mission (SRTM) supplied the elevation data; Landsat data from November 11, 1986 provided the land surface color (not the sky) and U.S. Geological Survey digital aerial photography provides the image detail. The Rose Bowl, surrounded by a golf course, is the circular feature at the bottom center of the image. The Jet Propulsion Laboratory is the cluster of large buildings north of the Rose Bowl at the base of the mountains. A large landfill, Scholl Canyon, is the smooth area in the lower left corner of the scene. This image shows the power of combining data from different sources to create planning tools to study problems that affect large urban areas. In addition to the well-known earthquake hazards, Southern California is affected by a natural cycle of fire and mudflows. Wildfires strip the mountains of vegetation, increasing the hazards from flooding and mudflows for several years afterwards. Data such as shown on this image can be used to predict both how wildfires will spread over the terrain and also how mudflows will be channeled down the canyons. The Shuttle Radar Topography Mission (SRTM), launched on February 11, 2000, uses the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) that flew twice on the Space Shuttle Endeavour in 1994. The mission was designed to collect three dimensional measurements of the Earth's surface. To collect the 3-D data, engineers added a 60-meter-long (200-foot) mast, an additional C-band imaging antenna and improved tracking and navigation devices. The mission is a cooperative project between the National Aeronautics and Space Administration (NASA), the National Imagery and Mapping Agency

  11. Identification of inelastic parameters based on deep drawing forming operations using a global-local hybrid Particle Swarm approach

    NASA Astrophysics Data System (ADS)

    Vaz, Miguel; Luersen, Marco A.; Muñoz-Rojas, Pablo A.; Trentin, Robson G.

    2016-04-01

    Application of optimization techniques to the identification of inelastic material parameters has substantially increased in recent years. The complex stress-strain paths and high nonlinearity, typical of this class of problems, require the development of robust and efficient techniques for inverse problems able to account for an irregular topography of the fitness surface. Within this framework, this work investigates the application of the gradient-based Sequential Quadratic Programming method, of the Nelder-Mead downhill simplex algorithm, of Particle Swarm Optimization (PSO), and of a global-local PSO-Nelder-Mead hybrid scheme to the identification of inelastic parameters based on a deep drawing operation. The hybrid technique has shown to be the best strategy by combining the good PSO performance to approach the global minimum basin of attraction with the efficiency demonstrated by the Nelder-Mead algorithm to obtain the minimum itself.

  12. MOSSFRAC: An anisotropic 3D fracture model

    SciTech Connect

    Moss, W C; Levatin, J L

    2006-08-14

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

  13. Aircraft Observations of Water Vapor Transport in Atmospheric Rivers: Synthesis from Seven Events Using Dropsonde Data from the NASA Global Hawk, NOAA G-IV, and NOAA WP-3D

    NASA Astrophysics Data System (ADS)

    Ralph, F. M.; Wick, G. A.; Neiman, P. J.; Spackman, J. R.; Song, Y.; Hock, T.

    2011-12-01

    Atmospheric water vapor transport is a critical component of the global water cycle and in precipitation formation and prediction. Over roughly the last 15 years research efforts have identified atmospheric rivers (AR) as the primary mechanism for transporting water vapor in the mid latitudes, and possibly from the tropics into the midlatitudes. Numerous studies have used either satellite observations of vertically integrated water vapor (IWV) over the ocean or numerical models to examine AR-related water vapor transport. Some studies have been able to take advantage of vertical profiling information at the coast, and a handful of other studies have been able to carry out aircraft observations over the oceans. This paper is intended to fill a major observational gap associated with quantifying the total amount of water vapor transport in several ARs using a unique set of dropsonde observations using research aircraft. The research addresses research objectives of CalWater associated with ARs. The analysis includes observations from 3 flights of the NASA Global Hawk unmanned aircraft in the NOAA-led Winter Storms and Pacific Atmospheric Rivers (WISPAR) field campaign that demonstrated for the first time a new dropsonde system built by NCAR for NOAA specifically for use on the Global Hawk. It will also document whether tropical water vapor was entrained into the southern extension of two strong ARs. The study will also compare the observed characteristics of the AR water vapor transport (max IWV, max low-altitude winds, max local water vapor transport, and total water vapor transport across the depth and width of the AR) with standard meteorological analyses from the operational GFS numerical weather prediction model and from the 1/2 deg Climate Forecast System reanalysis (CFSR), the 32 km NARR, the NASA MERRA, and the coarser NCEP-NCAR Reanalysis. Observations from the following field experiments and aircraft will be used: - CalJet, NOAA P-3, 25-26 January 1998

  14. Quasi-3D Algorithm in Multi-scale Modeling Framework

    NASA Astrophysics Data System (ADS)

    Jung, J.; Arakawa, A.

    2008-12-01

    As discussed in the companion paper by Arakawa and Jung, the Quasi-3D (Q3D) Multi-scale Modeling Framework (MMF) is a 4D estimation/prediction framework that combines a GCM with a 3D anelastic vector vorticity equation model (VVM) applied to a Q3D network of horizontal grid points. This paper presents an outline of the recently revised Q3D algorithm and a highlight of the results obtained by application of the algorithm to an idealized model setting. The Q3D network of grid points consists of two sets of grid-point arrays perpendicular to each other. For a scalar variable, for example, each set consists of three parallel rows of grid points. Principal and supplementary predictions are made on the central and the two adjacent rows, respectively. The supplementary prediction is to allow the principal prediction be three-dimensional at least to the second-order accuracy. To accommodate a higher-order accuracy and to make the supplementary predictions formally three-dimensional, a few rows of ghost points are added at each side of the array. Values at these ghost points are diagnostically determined by a combination of statistical estimation and extrapolation. The basic structure of the estimation algorithm is determined in view of the global stability of Q3D advection. The algorithm is calibrated using the statistics of past data at and near the intersections of the two sets of grid- point arrays. Since the CRM in the Q3D MMF extends beyond individual GCM boxes, the CRM can be a GCM by itself. However, it is better to couple the CRM with the GCM because (1) the CRM is a Q3D CRM based on a highly anisotropic network of grid points and (2) coupling with a GCM makes it more straightforward to inherit our experience with the conventional GCMs. In the coupled system we have selected, prediction of thermdynamic variables is almost entirely done by the Q3D CRM with no direct forcing by the GCM. The coupling of the dynamics between the two components is through mutual

  15. Case study: Beauty and the Beast 3D: benefits of 3D viewing for 2D to 3D conversion

    NASA Astrophysics Data System (ADS)

    Handy Turner, Tara

    2010-02-01

    From the earliest stages of the Beauty and the Beast 3D conversion project, the advantages of accurate desk-side 3D viewing was evident. While designing and testing the 2D to 3D conversion process, the engineering team at Walt Disney Animation Studios proposed a 3D viewing configuration that not only allowed artists to "compose" stereoscopic 3D but also improved efficiency by allowing artists to instantly detect which image features were essential to the stereoscopic appeal of a shot and which features had minimal or even negative impact. At a time when few commercial 3D monitors were available and few software packages provided 3D desk-side output, the team designed their own prototype devices and collaborated with vendors to create a "3D composing" workstation. This paper outlines the display technologies explored, final choices made for Beauty and the Beast 3D, wish-lists for future development and a few rules of thumb for composing compelling 2D to 3D conversions.

  16. Dark matter in 3D

    DOE PAGES

    Alves, Daniele S. M.; El Hedri, Sonia; Wacker, Jay G.

    2016-03-21

    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 methodmore » using the Via Lactea II N-body simulation as well as an analytical model for the dark matter halo. Furthermore, we conclude that O(1000) events are necessary to measure deviations from the Standard Halo Model and constrain or measure the presence of anisotropies.« less

  17. Dark matter in 3D

    SciTech Connect

    Alves, Daniele S. M.; El Hedri, Sonia; Wacker, Jay G.

    2016-03-21

    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. Furthermore, we conclude that O(1000) events are necessary to measure deviations from the Standard Halo Model and constrain or measure the presence of anisotropies.

  18. Dark Matter in 3D

    SciTech Connect

    Alves, Daniele S.M.; Hedri, Sonia El; Wacker, Jay G.

    2012-04-01

    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 constrain or measure the presence of anisotropies.

  19. Mini 3D for shallow gas reconnaissance

    SciTech Connect

    Vallieres, T. des; Enns, D.; Kuehn, H.; Parron, D.; Lafet, Y.; Van Hulle, D.

    1996-12-31

    The Mini 3D project was undertaken by TOTAL and ELF with the support of CEPM (Comite d`Etudes Petrolieres et Marines) to define an economical method of obtaining 3D seismic HR data for shallow gas assessment. An experimental 3D survey was carried out with classical site survey techniques in the North Sea. From these data 19 simulations, were produced to compare different acquisition geometries ranging from dual, 600 m long cables to a single receiver. Results show that short offset, low fold and very simple streamer positioning are sufficient to give a reliable 3D image of gas charged bodies. The 3D data allow a much more accurate risk delineation than 2D HR data. Moreover on financial grounds Mini-3D is comparable in cost to a classical HR 2D survey. In view of these results, such HR 3D should now be the standard for shallow gas surveying.

  20. The Feasibility of 3d Point Cloud Generation from Smartphones

    NASA Astrophysics Data System (ADS)

    Alsubaie, N.; El-Sheimy, N.

    2016-06-01

    This paper proposes a new technique for increasing the accuracy of direct geo-referenced image-based 3D point cloud generated from low-cost sensors in smartphones. The smartphone's motion sensors are used to directly acquire the Exterior Orientation Parameters (EOPs) of the captured images. These EOPs, along with the Interior Orientation Parameters (IOPs) of the camera/ phone, are used to reconstruct the image-based 3D point cloud. However, because smartphone motion sensors suffer from poor GPS accuracy, accumulated drift and high signal noise, inaccurate 3D mapping solutions often result. Therefore, horizontal and vertical linear features, visible in each image, are extracted and used as constraints in the bundle adjustment procedure. These constraints correct the relative position and orientation of the 3D mapping solution. Once the enhanced EOPs are estimated, the semi-global matching algorithm (SGM) is used to generate the image-based dense 3D point cloud. Statistical analysis and assessment are implemented herein, in order to demonstrate the feasibility of 3D point cloud generation from the consumer-grade sensors in smartphones.

  1. Deep Nonlinear Metric Learning for 3-D Shape Retrieval.

    PubMed

    Xie, Jin; Dai, Guoxian; Zhu, Fan; Shao, Ling; Fang, Yi

    2016-12-28

    Effective 3-D shape retrieval is an important problem in 3-D shape analysis. Recently, feature learning-based shape retrieval methods have been widely studied, where the distance metrics between 3-D shape descriptors are usually hand-crafted. In this paper, motivated by the fact that deep neural network has the good ability to model nonlinearity, we propose to learn an effective nonlinear distance metric between 3-D shape descriptors for retrieval. First, the locality-constrained linear coding method is employed to encode each vertex on the shape and the encoding coefficient histogram is formed as the global 3-D shape descriptor to represent the shape. Then, a novel deep metric network is proposed to learn a nonlinear transformation to map the 3-D shape descriptors to a nonlinear feature space. The proposed deep metric network minimizes a discriminative loss function that can enforce the similarity between a pair of samples from the same class to be small and the similarity between a pair of samples from different classes to be large. Finally, the distance between the outputs of the metric network is used as the similarity for shape retrieval. The proposed method is evaluated on the McGill, SHREC'10 ShapeGoogle, and SHREC'14 Human shape datasets. Experimental results on the three datasets validate the effectiveness of the proposed method.

  2. 3D laser imaging for concealed object identification

    NASA Astrophysics Data System (ADS)

    Berechet, Ion; Berginc, Gérard; Berechet, Stefan

    2014-09-01

    This paper deals with new optical non-conventional 3D laser imaging. Optical non-conventional imaging explores the advantages of laser imaging to form a three-dimensional image of the scene. 3D laser imaging can be used for threedimensional medical imaging, topography, surveillance, robotic vision because of ability to detect and recognize objects. In this paper, we present a 3D laser imaging for concealed object identification. The objective of this new 3D laser imaging is to provide the user a complete 3D reconstruction of the concealed object from available 2D data limited in number and with low representativeness. The 2D laser data used in this paper come from simulations that are based on the calculation of the laser interactions with the different interfaces of the scene of interest and from experimental results. We show the global 3D reconstruction procedures capable to separate objects from foliage and reconstruct a threedimensional image of the considered object. In this paper, we present examples of reconstruction and completion of three-dimensional images and we analyse the different parameters of the identification process such as resolution, the scenario of camouflage, noise impact and lacunarity degree.

  3. Robust Reconstruction and Generalized Dual Hahn Moments Invariants Extraction for 3D Images

    NASA Astrophysics Data System (ADS)

    Mesbah, Abderrahim; Zouhri, Amal; El Mallahi, Mostafa; Zenkouar, Khalid; Qjidaa, Hassan

    2017-03-01

    In this paper, we introduce a new set of 3D weighed dual Hahn moments which are orthogonal on a non-uniform lattice and their polynomials are numerically stable to scale, consequent, producing a set of weighted orthonormal polynomials. The dual Hahn is the general case of Tchebichef and Krawtchouk, and the orthogonality of dual Hahn moments eliminates the numerical approximations. The computational aspects and symmetry property of 3D weighed dual Hahn moments are discussed in details. To solve their inability to invariability of large 3D images, which cause to overflow issues, a generalized version of these moments noted 3D generalized weighed dual Hahn moment invariants are presented where whose as linear combination of regular geometric moments. For 3D pattern recognition, a generalized expression of 3D weighted dual Hahn moment invariants, under translation, scaling and rotation transformations, have been proposed where a new set of 3D-GWDHMIs have been provided. In experimental studies, the local and global capability of free and noisy 3D image reconstruction of the 3D-WDHMs has been compared with other orthogonal moments such as 3D Tchebichef and 3D Krawtchouk moments using Princeton Shape Benchmark database. On pattern recognition using the 3D-GWDHMIs like 3D object descriptors, the experimental results confirm that the proposed algorithm is more robust than other orthogonal moments for pattern classification of 3D images with and without noise.

  4. Alignment-independent technique for 3D QSAR analysis.

    PubMed

    Wilkes, Jon G; Stoyanova-Slavova, Iva B; Buzatu, Dan A

    2016-04-01

    Molecular biochemistry is controlled by 3D phenomena but structure-activity models based on 3D descriptors are infrequently used for large data sets because of the computational overhead for determining molecular conformations. A diverse dataset of 146 androgen receptor binders was used to investigate how different methods for defining molecular conformations affect the performance of 3D-quantitative spectral data activity relationship models. Molecular conformations tested: (1) global minimum of molecules' potential energy surface; (2) alignment-to-templates using equal electronic and steric force field contributions; (3) alignment using contributions "Best-for-Each" template; (4) non-energy optimized, non-aligned (2D > 3D). Aggregate predictions from models were compared. Highest average coefficients of determination ranged from R Test (2) = 0.56 to 0.61. The best model using 2D > 3D (imported directly from ChemSpider) produced R Test (2) = 0.61. It was superior to energy-minimized and conformation-aligned models and was achieved in only 3-7 % of the time required using the other conformation strategies. Predictions averaged from models built on different conformations achieved a consensus R Test (2) = 0.65. The best 2D > 3D model was analyzed for underlying structure-activity relationships. For the compound strongest binding to the androgen receptor, 10 substructural features contributing to binding were flagged. Utility of 2D > 3D was compared for two other activity endpoints, each modeling a medium sized data set. Results suggested that large scale, accurate predictions using 2D > 3D SDAR descriptors may be produced for interactions involving endocrine system nuclear receptors and other data sets in which strongest activities are produced by fairly inflexible substrates.

  5. Alignment-independent technique for 3D QSAR analysis

    NASA Astrophysics Data System (ADS)

    Wilkes, Jon G.; Stoyanova-Slavova, Iva B.; Buzatu, Dan A.

    2016-04-01

    Molecular biochemistry is controlled by 3D phenomena but structure-activity models based on 3D descriptors are infrequently used for large data sets because of the computational overhead for determining molecular conformations. A diverse dataset of 146 androgen receptor binders was used to investigate how different methods for defining molecular conformations affect the performance of 3D-quantitative spectral data activity relationship models. Molecular conformations tested: (1) global minimum of molecules' potential energy surface; (2) alignment-to-templates using equal electronic and steric force field contributions; (3) alignment using contributions "Best-for-Each" template; (4) non-energy optimized, non-aligned (2D > 3D). Aggregate predictions from models were compared. Highest average coefficients of determination ranged from R Test 2 = 0.56 to 0.61. The best model using 2D > 3D (imported directly from ChemSpider) produced R Test 2 = 0.61. It was superior to energy-minimized and conformation-aligned models and was achieved in only 3-7 % of the time required using the other conformation strategies. Predictions averaged from models built on different conformations achieved a consensus R Test 2 = 0.65. The best 2D > 3D model was analyzed for underlying structure-activity relationships. For the compound strongest binding to the androgen receptor, 10 substructural features contributing to binding were flagged. Utility of 2D > 3D was compared for two other activity endpoints, each modeling a medium sized data set. Results suggested that large scale, accurate predictions using 2D > 3D SDAR descriptors may be produced for interactions involving endocrine system nuclear receptors and other data sets in which strongest activities are produced by fairly inflexible substrates.

  6. The agreement between 3D, standard 2D and triplane 2D speckle tracking: effects of image quality and 3D volume rate.

    PubMed

    Trache, Tudor; Stöbe, Stephan; Tarr, Adrienn; Pfeiffer, Dietrich; Hagendorff, Andreas

    2014-12-01

    Comparison of 3D and 2D speckle tracking performed on standard 2D and triplane 2D datasets of normal and pathological left ventricular (LV) wall-motion patterns with a focus on the effect that 3D volume rate (3DVR), image quality and tracking artifacts have on the agreement between 2D and 3D speckle tracking. 37 patients with normal LV function and 18 patients with ischaemic wall-motion abnormalities underwent 2D and 3D echocardiography, followed by offline speckle tracking measurements. The values of 3D global, regional and segmental strain were compared with the standard 2D and triplane 2D strain values. Correlation analysis with the LV ejection fraction (LVEF) was also performed. The 3D and 2D global strain values correlated good in both normally and abnormally contracting hearts, though systematic differences between the two methods were observed. Of the 3D strain parameters, the area strain showed the best correlation with the LVEF. The numerical agreement of 3D and 2D analyses varied significantly with the volume rate and image quality of the 3D datasets. The highest correlation between 2D and 3D peak systolic strain values was found between 3D area and standard 2D longitudinal strain. Regional wall-motion abnormalities were similarly detected by 2D and 3D speckle tracking. 2DST of triplane datasets showed similar results to those of conventional 2D datasets. 2D and 3D speckle tracking similarly detect normal and pathological wall-motion patterns. Limited image quality has a significant impact on the agreement between 3D and 2D numerical strain values.

  7. Exploring the limit of accuracy for density functionals based on the generalized gradient approximation: Local, global hybrid, and range-separated hybrid functionals with and without dispersion corrections

    SciTech Connect

    Mardirossian, Narbe; Head-Gordon, Martin

    2014-05-14

    The limit of accuracy for semi-empirical generalized gradient approximation (GGA) density functionals is explored by parameterizing a variety of local, global hybrid, and range-separated hybrid functionals. The training methodology employed differs from conventional approaches in 2 main ways: (1) Instead of uniformly truncating the exchange, same-spin correlation, and opposite-spin correlation functional inhomogeneity correction factors, all possible fits up to fourth order are considered, and (2) Instead of selecting the optimal functionals based solely on their training set performance, the fits are validated on an independent test set and ranked based on their overall performance on the training and test sets. The 3 different methods of accounting for exchange are trained both with and without dispersion corrections (DFT-D2 and VV10), resulting in a total of 491 508 candidate functionals. For each of the 9 functional classes considered, the results illustrate the trade-off between improved training set performance and diminished transferability. Since all 491 508 functionals are uniformly trained and tested, this methodology allows the relative strengths of each type of functional to be consistently compared and contrasted. The range-separated hybrid GGA functional paired with the VV10 nonlocal correlation functional emerges as the most accurate form for the present training and test sets, which span thermochemical energy differences, reaction barriers, and intermolecular interactions involving lighter main group elements.

  8. Exploring the limit of accuracy for density functionals based on the generalized gradient approximation: Local, global hybrid, and range-separated hybrid functionals with and without dispersion corrections

    NASA Astrophysics Data System (ADS)

    Mardirossian, Narbe; Head-Gordon, Martin

    2014-05-01

    The limit of accuracy for semi-empirical generalized gradient approximation (GGA) density functionals is explored by parameterizing a variety of local, global hybrid, and range-separated hybrid functionals. The training methodology employed differs from conventional approaches in 2 main ways: (1) Instead of uniformly truncating the exchange, same-spin correlation, and opposite-spin correlation functional inhomogeneity correction factors, all possible fits up to fourth order are considered, and (2) Instead of selecting the optimal functionals based solely on their training set performance, the fits are validated on an independent test set and ranked based on their overall performance on the training and test sets. The 3 different methods of accounting for exchange are trained both with and without dispersion corrections (DFT-D2 and VV10), resulting in a total of 491 508 candidate functionals. For each of the 9 functional classes considered, the results illustrate the trade-off between improved training set performance and diminished transferability. Since all 491 508 functionals are uniformly trained and tested, this methodology allows the relative strengths of each type of functional to be consistently compared and contrasted. The range-separated hybrid GGA functional paired with the VV10 nonlocal correlation functional emerges as the most accurate form for the present training and test sets, which span thermochemical energy differences, reaction barriers, and intermolecular interactions involving lighter main group elements.

  9. 3-D Technology Approaches for Biological Ecologies

    NASA Astrophysics Data System (ADS)

    Liu, Liyu; Austin, Robert; U. S-China Physical-Oncology Sciences Alliance (PS-OA) Team

    Constructing three dimensional (3-D) landscapes is an inevitable issue in deep study of biological ecologies, because in whatever scales in nature, all of the ecosystems are composed by complex 3-D environments and biological behaviors. Just imagine if a 3-D technology could help complex ecosystems be built easily and mimic in vivo microenvironment realistically with flexible environmental controls, it will be a fantastic and powerful thrust to assist researchers for explorations. For years, we have been utilizing and developing different technologies for constructing 3-D micro landscapes for biophysics studies in in vitro. Here, I will review our past efforts, including probing cancer cell invasiveness with 3-D silicon based Tepuis, constructing 3-D microenvironment for cell invasion and metastasis through polydimethylsiloxane (PDMS) soft lithography, as well as explorations of optimized stenting positions for coronary bifurcation disease with 3-D wax printing and the latest home designed 3-D bio-printer. Although 3-D technologies is currently considered not mature enough for arbitrary 3-D micro-ecological models with easy design and fabrication, I hope through my talk, the audiences will be able to sense its significance and predictable breakthroughs in the near future. This work was supported by the State Key Development Program for Basic Research of China (Grant No. 2013CB837200), the National Natural Science Foundation of China (Grant No. 11474345) and the Beijing Natural Science Foundation (Grant No. 7154221).

  10. 3D change detection - Approaches and applications

    NASA Astrophysics Data System (ADS)

    Qin, Rongjun; Tian, Jiaojiao; Reinartz, Peter

    2016-12-01

    Due to the unprecedented technology development of sensors, platforms and algorithms for 3D data acquisition and generation, 3D spaceborne, airborne and close-range data, in the form of image based, Light Detection and Ranging (LiDAR) based point clouds, Digital Elevation Models (DEM) and 3D city models, become more accessible than ever before. Change detection (CD) or time-series data analysis in 3D has gained great attention due to its capability of providing volumetric dynamics to facilitate more applications and provide more accurate results. The state-of-the-art CD reviews aim to provide a comprehensive synthesis and to simplify the taxonomy of the traditional remote sensing CD techniques, which mainly sit within the boundary of 2D image/spectrum analysis, largely ignoring the particularities of 3D aspects of the data. The inclusion of 3D data for change detection (termed 3D CD), not only provides a source with different modality for analysis, but also transcends the border of traditional top-view 2D pixel/object-based analysis to highly detailed, oblique view or voxel-based geometric analysis. This paper reviews the recent developments and applications of 3D CD using remote sensing and close-range data, in support of both academia and industry researchers who seek for solutions in detecting and analyzing 3D dynamics of various objects of interest. We first describe the general considerations of 3D CD problems in different processing stages and identify CD types based on the information used, being the geometric comparison and geometric-spectral analysis. We then summarize relevant works and practices in urban, environment, ecology and civil applications, etc. Given the broad spectrum of applications and different types of 3D data, we discuss important issues in 3D CD methods. Finally, we present concluding remarks in algorithmic aspects of 3D CD.

  11. RT3D tutorials for GMS users

    SciTech Connect

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

    1998-02-01

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

  12. An Effective 3D Shape Descriptor for Object Recognition with RGB-D Sensors

    PubMed Central

    Liu, Zhong; Zhao, Changchen; Wu, Xingming; Chen, Weihai

    2017-01-01

    RGB-D sensors have been widely used in various areas of computer vision and graphics. A good descriptor will effectively improve the performance of operation. This article further analyzes the recognition performance of shape features extracted from multi-modality source data using RGB-D sensors. A hybrid shape descriptor is proposed as a representation of objects for recognition. We first extracted five 2D shape features from contour-based images and five 3D shape features over point cloud data to capture the global and local shape characteristics of an object. The recognition performance was tested for category recognition and instance recognition. Experimental results show that the proposed shape descriptor outperforms several common global-to-global shape descriptors and is comparable to some partial-to-global shape descriptors that achieved the best accuracies in category and instance recognition. Contribution of partial features and computational complexity were also analyzed. The results indicate that the proposed shape features are strong cues for object recognition and can be combined with other features to boost accuracy. PMID:28245553

  13. 3D measurement for rapid prototyping

    NASA Astrophysics Data System (ADS)

    Albrecht, Peter; Lilienblum, Tilo; Sommerkorn, Gerd; Michaelis, Bernd

    1996-08-01

    Optical 3-D measurement is an interesting approach for rapid prototyping. On one hand it's necessary to get the 3-D data of an object and on the other hand it's necessary to check the manufactured object (quality checking). Optical 3-D measurement can realize both. Classical 3-D measurement procedures based on photogrammetry cause systematic errors at strongly curved surfaces or steps in surfaces. One possibility to reduce these errors is to calculate the 3-D coordinates from several successively taken images. Thus it's possible to get higher spatial resolution and to reduce the systematic errors at 'problem surfaces.' Another possibility is to process the measurement values by neural networks. A modified associative memory smoothes and corrects the calculated 3-D coordinates using a-priori knowledge about the measurement object.

  14. Photorefractive Polymers for Updateable 3D Displays

    DTIC Science & Technology

    2010-02-24

    Final Performance Report 3. DATES COVERED (From - To) 01-01-2007 to 11-30-2009 4. TITLE AND SUBTITLE Photorefractive Polymers for Updateable 3D ...ABSTRACT During the tenure of this project a large area updateable 3D color display has been developed for the first time using a new co-polymer...photorefractive polymers have been demonstrated. Moreover, a 6 inch × 6 inch sample was fabricated demonstrating the feasibility of making large area 3D

  15. 3D Microperfusion Model of ADPKD

    DTIC Science & Technology

    2015-10-01

    Stratasys 3D printer . PDMS was cast in the negative molds in order to create permanent biocompatible plastic masters (SmoothCast 310). All goals of task...1 AWARD NUMBER: W81XWH-14-1-0304 TITLE: 3D Microperfusion Model of ADPKD PRINCIPAL INVESTIGATOR: David L. Kaplan CONTRACTING ORGANIZATION...ADDRESS. 1. REPORT DATE October 2015 2. REPORT TYPE Annual Report 3. DATES COVERED 15 Sep 2014 - 14 Sep 2015 4. TITLE AND SUBTITLE 3D

  16. 3D carotid plaque MR Imaging

    PubMed Central

    Parker, Dennis L.

    2015-01-01

    SYNOPSIS There has been significant progress made in 3D carotid plaque magnetic resonance imaging techniques in recent years. 3D plaque imaging clearly represents the future in clinical use. With effective flow suppression techniques, choices of different contrast weighting acquisitions, and time-efficient imaging approaches, 3D plaque imaging offers flexible imaging plane and view angle analysis, large coverage, multi-vascular beds capability, and even can be used in fast screening. PMID:26610656

  17. 3-D Extensions for Trustworthy Systems

    DTIC Science & Technology

    2011-01-01

    3- D Extensions for Trustworthy Systems (Invited Paper) Ted Huffmire∗, Timothy Levin∗, Cynthia Irvine∗, Ryan Kastner† and Timothy Sherwood...address these problems, we propose an approach to trustworthy system development based on 3- D integration, an emerging chip fabrication technique in...which two or more integrated circuit dies are fabricated individually and then combined into a single stack using vertical conductive posts. With 3- D

  18. Hardware Trust Implications of 3-D Integration

    DTIC Science & Technology

    2010-12-01

    enhancing a commod- ity processor with a variety of security functions. This paper examines the 3-D design approach and provides an analysis concluding...of key components. The question addressed by this paper is, “Can a 3-D control plane provide useful secure services when it is conjoined with an...untrust- worthy computation plane?” Design-level investigation of this question yields a definite yes. This paper explores 3- D applications and their

  19. Digital holography and 3-D imaging.

    PubMed

    Banerjee, Partha; Barbastathis, George; Kim, Myung; Kukhtarev, Nickolai

    2011-03-01

    This feature issue on Digital Holography and 3-D Imaging comprises 15 papers on digital holographic techniques and applications, computer-generated holography and encryption techniques, and 3-D display. It is hoped that future work in the area leads to innovative applications of digital holography and 3-D imaging to biology and sensing, and to the development of novel nonlinear dynamic digital holographic techniques.

  20. Dimensional accuracy of 3D printed vertebra

    NASA Astrophysics Data System (ADS)

    Ogden, Kent; Ordway, Nathaniel; Diallo, Dalanda; Tillapaugh-Fay, Gwen; Aslan, Can

    2014-03-01

    3D printer applications in the biomedical sciences and medical imaging are expanding and will have an increasing impact on the practice of medicine. Orthopedic and reconstructive surgery has been an obvious area for development of 3D printer applications as the segmentation of bony anatomy to generate printable models is relatively straightforward. There are important issues that should be addressed when using 3D printed models for applications that may affect patient care; in particular the dimensional accuracy of the printed parts needs to be high to avoid poor decisions being made prior to surgery or therapeutic procedures. In this work, the dimensional accuracy of 3D printed vertebral bodies derived from CT data for a cadaver spine is compared with direct measurements on the ex-vivo vertebra and with measurements made on the 3D rendered vertebra using commercial 3D image processing software. The vertebra was printed on a consumer grade 3D printer using an additive print process using PLA (polylactic acid) filament. Measurements were made for 15 different anatomic features of the vertebral body, including vertebral body height, endplate width and depth, pedicle height and width, and spinal canal width and depth, among others. It is shown that for the segmentation and printing process used, the results of measurements made on the 3D printed vertebral body are substantially the same as those produced by direct measurement on the vertebra and measurements made on the 3D rendered vertebra.

  1. Cloud-resolving component in the quasi-3D multi-scale modeling framework

    NASA Astrophysics Data System (ADS)

    Jung, Joon-Hee; Arakawa, Akio

    2010-05-01

    A quasi-3D multi-scale modeling framework (Q3D MMF), which combines a GCM with a Q3D CRM, is an attempt to include three dimensional cloud effects in a GCM without necessarily using a global cloud-resolving model. The horizontal domain of the Q3D CRM consists of two perpendicular sets of channels crossing at the center of a GCM grid box, each of which includes two grid-point arrays. Through coupling this structure with a GCM, the whole system of the Q3D MMF can converge to a fully 3D global CRM as the GCM's resolution is refined. Consequently, the horizontal resolution of the GCM can be freely chosen depending on the objective of application. However, due to the use of very narrow channels for the cloud-resolving component, its prediction algorithm must be specially designed. As a step in developing a Q3D MMF, we have first constructed a prediction algorithm for the Q3D CRM applying a 3D anelastic vector vorticity equation model to the Q3D network of grid points. Preliminary tests of the Q3D CRM have been performed for an idealized small domain. Comparing the results with those of the straightforward application of a 3D CRM, it is concluded that the Q3D CRM can reproduce most of the important statistics of the 3D solutions and the MMF based on the Q3D CRM will be a useful framework for climate modeling. This paper presents an outline of the Q3D algorithm and highlights of the results.

  2. 3-D General Relativistic MHD Simulations of Generating Jets

    NASA Astrophysics Data System (ADS)

    Nishikawa, K.-I.; Koide, S.; Shibata, K.; Kudoh, T.; Frank, J.; Sol, H.

    1999-05-01

    Koide et al have investigated the dynamics of an accretion disk initially threaded by a uniform poloidal magnetic field in a non-rotating corona (either in a steady-state infalling state or in hydrostatic equilibrium) around a non-rotating black hole using a 3-D GRMHD with the ``axisymmetry'' along the z-direction. Magnetic field is tightly twisted by the rotation of the disk, and plasmas in the shocked region of the disk are accelerated by J x B force to form bipolar relativistic jets. In order to investigate variabilities of generated relativistic jets and magnetic field structure inside jets, we have performed calculations using the 3-D GRMHD code on a full 3-dimensional system. We will investigate how the third dimension affects the global disk dynamics. 3-D RMHD simulations wil be also performed to investigate the dynamics of a jet with a helical mangetic field in it.

  3. FastScript3D - A Companion to Java 3D

    NASA Technical Reports Server (NTRS)

    Koenig, Patti

    2005-01-01

    FastScript3D is a computer program, written in the Java 3D(TM) programming language, that establishes an alternative language that helps users who lack expertise in Java 3D to use Java 3D for constructing three-dimensional (3D)-appearing graphics. The FastScript3D language provides a set of simple, intuitive, one-line text-string commands for creating, controlling, and animating 3D models. The first word in a string is the name of a command; the rest of the string contains the data arguments for the command. The commands can also be used as an aid to learning Java 3D. Developers can extend the language by adding custom text-string commands. The commands can define new 3D objects or load representations of 3D objects from files in formats compatible with such other software systems as X3D. The text strings can be easily integrated into other languages. FastScript3D facilitates communication between scripting languages [which enable programming of hyper-text markup language (HTML) documents to interact with users] and Java 3D. The FastScript3D language can be extended and customized on both the scripting side and the Java 3D side.

  4. Episcopic 3D Imaging Methods: Tools for Researching Gene Function

    PubMed Central

    Weninger, Wolfgang J; Geyer, Stefan H

    2008-01-01

    This work aims at describing episcopic 3D imaging methods and at discussing how these methods can contribute to researching the genetic mechanisms driving embryogenesis and tissue remodelling, and the genesis of pathologies. Several episcopic 3D imaging methods exist. The most advanced are capable of generating high-resolution volume data (voxel sizes from 0.5x0.5x1 µm upwards) of small to large embryos of model organisms and tissue samples. Beside anatomy and tissue architecture, gene expression and gene product patterns can be three dimensionally analyzed in their precise anatomical and histological context with the aid of whole mount in situ hybridization or whole mount immunohistochemical staining techniques. Episcopic 3D imaging techniques were and are employed for analyzing the precise morphological phenotype of experimentally malformed, randomly produced, or genetically engineered embryos of biomedical model organisms. It has been shown that episcopic 3D imaging also fits for describing the spatial distribution of genes and gene products during embryogenesis, and that it can be used for analyzing tissue samples of adult model animals and humans. The latter offers the possibility to use episcopic 3D imaging techniques for researching the causality a