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Sample records for harmonic 3d power

  1. 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.

  2. Feasibility of 3D harmonic contrast imaging.

    PubMed

    Voormolen, M M; Bouakaz, A; Krenning, B J; Lancée, C T; ten Cate, F J; de Jong, N

    2004-04-01

    Improved endocardial border delineation with the application of contrast agents should allow for less complex and faster tracing algorithms for left ventricular volume analysis. We developed a fast rotating phased array transducer for 3D imaging of the heart with harmonic capabilities making it suitable for contrast imaging. In this study the feasibility of 3D harmonic contrast imaging is evaluated in vitro. A commercially available tissue mimicking flow phantom was used in combination with Sonovue. Backscatter power spectra from a tissue and contrast region of interest were calculated from recorded radio frequency data. The spectra and the extracted contrast to tissue ratio from these spectra were used to optimize the excitation frequency, the pulse length and the receive filter settings of the transducer. Frequencies ranging from 1.66 to 2.35 MHz and pulse lengths of 1.5, 2 and 2.5 cycles were explored. An increase of more than 15 dB in the contrast to tissue ratio was found around the second harmonic compared with the fundamental level at an optimal excitation frequency of 1.74 MHz and a pulse length of 2.5 cycles. Using the optimal settings for 3D harmonic contrast recordings volume measurements of a left ventricular shaped agar phantom were performed. Without contrast the extracted volume data resulted in a volume error of 1.5%, with contrast an accuracy of 3.8% was achieved. The results show the feasibility of accurate volume measurements from 3D harmonic contrast images. Further investigations will include the clinical evaluation of the presented technique for improved assessment of the heart.

  3. 3D Left Ventricular Strain from Unwrapped Harmonic Phase Measurements

    PubMed Central

    Venkatesh, Bharath Ambale; Gupta, Himanshu; Lloyd, Steven G.; ‘Italia, Louis Dell; Denney, Thomas S.

    2010-01-01

    Purpose To validate a method for measuring 3D left ventricular (LV) strain from phase-unwrapped harmonic phase (HARP) images derived from tagged cardiac magnetic resonance imaging (MRI). Materials and Methods A set of 40 human subjects were imaged with tagged MRI. In each study HARP phase was computed and unwrapped in each short-axis and long-axis image. Inconsistencies in unwrapped phase were resolved using branch cuts manually placed with a graphical user interface. 3D strain maps were computed for all imaged timeframes in each study. The strain from unwrapped phase (SUP) and displacements were compared to those estimated by a feature-based (FB) technique and a HARP technique. Results 3D strain was computed in each timeframe through systole and mid diastole in approximately 30 minutes per study. The standard deviation of the difference between strains measured by the FB and the SUP methods was less than 5% of the average of the strains from the two methods. The correlation between peak circumferential strain measured using the SUP and HARP techniques was over 83%. Conclusion The SUP technique can reconstruct full 3-D strain maps from tagged MR images through the cardiac cycle in a reasonable amount of time and user interaction compared to other 3D analysis methods. PMID:20373429

  4. A non-conforming 3D spherical harmonic transport solver

    SciTech Connect

    Van Criekingen, S.

    2006-07-01

    A new 3D transport solver for the time-independent Boltzmann transport equation has been developed. This solver is based on the second-order even-parity form of the transport equation. The angular discretization is performed through the expansion of the angular neutron flux in spherical harmonics (PN method). The novelty of this solver is the use of non-conforming finite elements for the spatial discretization. Such elements lead to a discontinuous flux approximation. This interface continuity requirement relaxation property is shared with mixed-dual formulations such as the ones based on Raviart-Thomas finite elements. Encouraging numerical results are presented. (authors)

  5. A spherical harmonics intensity model for 3D segmentation and 3D shape analysis of heterochromatin foci.

    PubMed

    Eck, Simon; Wörz, Stefan; Müller-Ott, Katharina; Hahn, Matthias; Biesdorf, Andreas; Schotta, Gunnar; Rippe, Karsten; Rohr, Karl

    2016-08-01

    The genome is partitioned into regions of euchromatin and heterochromatin. The organization of heterochromatin is important for the regulation of cellular processes such as chromosome segregation and gene silencing, and their misregulation is linked to cancer and other diseases. We present a model-based approach for automatic 3D segmentation and 3D shape analysis of heterochromatin foci from 3D confocal light microscopy images. Our approach employs a novel 3D intensity model based on spherical harmonics, which analytically describes the shape and intensities of the foci. The model parameters are determined by fitting the model to the image intensities using least-squares minimization. To characterize the 3D shape of the foci, we exploit the computed spherical harmonics coefficients and determine a shape descriptor. We applied our approach to 3D synthetic image data as well as real 3D static and real 3D time-lapse microscopy images, and compared the performance with that of previous approaches. It turned out that our approach yields accurate 3D segmentation results and performs better than previous approaches. We also show that our approach can be used for quantifying 3D shape differences of heterochromatin foci.

  6. On 3D Riesz systems of harmonic conjugates

    NASA Astrophysics Data System (ADS)

    Avetisyan, K.; Gürlebeck, K.; Morais, J.

    2012-11-01

    This note announces some results that will be presented in the forthcoming paper [10]. In continuation to these studies we discuss a constructive approach for the generation of harmonic conjugates to find nullsolutions to the Riesz system in R3. This class of solutions coincides with the subclass of monogenic functions with values in the reduced quaternions. The algorithm for harmonic conjugates is presented by means of an integral representation. Additionally, we discuss the weighted (monogenic) Hardy and Bergman spaces on the unit ball in R3 consisting of functions with values in the reduced quaternions. We end up showing the boundedness of the underlying harmonic conjugation operators in certain weighted spaces.

  7. 3-D Printed High Power Microwave Magnetrons

    NASA Astrophysics Data System (ADS)

    Jordan, Nicholas; Greening, Geoffrey; Exelby, Steven; Gilgenbach, Ronald; Lau, Y. Y.; Hoff, Brad

    2015-11-01

    The size, weight, and power requirements of HPM systems are critical constraints on their viability, and can potentially be improved through the use of additive manufacturing techniques, which are rapidly increasing in capability and affordability. Recent experiments on the UM Recirculating Planar Magnetron (RPM), have explored the use of 3-D printed components in a HPM system. The system was driven by MELBA-C, a Marx-Abramyan system which delivers a -300 kV voltage pulse for 0.3-1.0 us, with a 0.15-0.3 T axial magnetic field applied by a pair of electromagnets. Anode blocks were printed from Water Shed XC 11122 photopolymer using a stereolithography process, and prepared with either a spray-coated or electroplated finish. Both manufacturing processes were compared against baseline data for a machined aluminum anode, noting any differences in power output, oscillation frequency, and mode stability. Evolution and durability of the 3-D printed structures were noted both visually and by tracking vacuum inventories via a residual gas analyzer. Research supported by AFOSR (grant #FA9550-15-1-0097) and AFRL.

  8. Coherent and squeezed states for the 3D harmonic oscillator

    NASA Astrophysics Data System (ADS)

    Mazouz, Amel; Bentaiba, Mustapha; Mahieddine, Ali

    2017-01-01

    A three-dimensional harmonic oscillator is studied in the context of generalized coherent states. We construct its squeezed states as eigenstates of linear contribution of ladder operators which are associated to the generalized Heisenberg algebra. We study the probability density to show the compression effect on the squeezed states. Our analysis reveals that squeezed states give us some freedom on the precise knowledge of position of the particle while maintaining the Heisenberg uncertainty relation minimum, squeezed states remains squeezed states over time.

  9. Living with power system harmonics

    SciTech Connect

    Palko, E.

    1992-06-18

    This paper reports the effect of harmonics on electronic equipment in manufacturing plants which was essentially a nonproblem as recently as nine years ago. In years past, harmonics were essentially a problem experienced by electric utility companies, with a relatively few types of industries impressing a serous degree of harmonics onto the utility system. Utilities typically solved their harmonic problems by imposing limits on the amount of harmonics that a customer was permitted to reflect onto the utility system, and assessing heavy financial penalties for noncompliance. Today's electronic equipment creates a problem that feeds on itself: solid-state electronic equipment is a flagrant generator of harmonics, and solid-state equipment is, itself, intolerant of harmonics and is susceptible to malfunction and failure when served from a harmonic-laden power source.

  10. Optimal-tradeoff circular harmonic function filters for 3D target recognition

    NASA Astrophysics Data System (ADS)

    Vijaya Kumar, Bhagavatula V. K.; Xie, Chunyan; Mahalanobis, Abhijit

    2003-09-01

    3D target recognition is of significant interest because representing the object in 3D space couuld essentially provide a solution to pose variation and self-occlusion problems that are big challenges in 2D pattern recognition. Correlation filers have been used in a variety of 2D pattern matching applications and many correlation filter designs have been developed to handle problems such as rotations. Correlation filters also offer other benefits such as shift-invariance, graceful degradation and closed-form solutions. The 3D extension of correlation filter is a natural extension to handle 3D pattern recognition problem. In this paper, we propose a 3D correlation filter design method based on cylindrical circular harmonic function (CCHF) and use LADAR imagery to illustrate the good performance of CCHF filters.

  11. Comparative study of reference currents and DC bus voltage control for Three-Phase Four-Wire Four-Leg SAPF to compensate harmonics and reactive power with 3D SVM.

    PubMed

    Chebabhi, A; Fellah, M K; Kessal, A; Benkhoris, M F

    2015-07-01

    In this paper the performances of three reference currents and DC bus voltage control techniques for Three-Phase Four-Wire Four-Leg SAPF are compared for balanced and unbalanced load conditions. The main goals are to minimize the harmonics, reduce the magnitude of neutral current, eliminate the zero-sequence current components caused by single-phase nonlinear loads and compensate the reactive power, and on the other hand improve performances such as robustness, stabilization, trajectory pursuit, and reduce time response. The three techniques are analyzed mathematically and simulation results are compared. The techniques considered for comparative study are the PI Control, Sliding Mode Control and the Backstepping Control. Synchronous reference frame theory (SRF) in the dqo-axes is used to generate the reference currents, of the inverter.

  12. Harmonic filters for 3D multichannel data: rotation invariant detection of mitoses in colorectal cancer.

    PubMed

    Schlachter, Matthias; Reisert, Marco; Herz, Corinna; Schlürmann, Fabienne; Lassmann, Silke; Werner, Martin; Burkhardt, Hans; Ronneberger, Olaf

    2010-08-01

    In this paper, we present a novel approach for a trainable rotation invariant detection of complex structures in 3D microscopic multichannel data using a nonlinear filter approach. The basic idea of our approach is to compute local features in a window around each 3D position and map these features by means of a nonlinear mapping onto new local harmonic descriptors of the local window. These local harmonic descriptors are then combined in a linear way to form the output of the filter. The optimal combination of the computed local harmonic descriptors is determined in previous training step, and allows the filter to be adapted to an arbitrary structure depending on the problem at hand. Our approach is not limited to scalar-valued images and can also be used for vector-valued (multichannel) images such as gradient vector flow fields. We present realizations of a scalar-valued and a vector-valued multichannel filter. Our proposed algorithm was quantitatively evaluated on colorectal cancer cell lines (cells grown under controlled conditions), on which we successfully detected complex 3D mitotic structures. For a qualitative evaluation we tested our algorithms on human 3D tissue samples of colorectal cancer. We compare our results with a steerable filter approach as well as a morphology-based approach.

  13. Quantitative Analysis of Vascular Heterogeneity in Breast Lesions Using Contrast-Enhanced 3-D Harmonic and Subharmonic Ultrasound Imaging

    PubMed Central

    Sridharan, Anush; Eisenbrey, John R.; Machado, Priscilla; Ojeda-Fournier, Haydee; Wilkes, Annina; Sevrukov, Alexander; Mattrey, Robert F.; Wallace, Kirk; Chalek, Carl L.; Thomenius, Kai E.; Forsberg, Flemming

    2015-01-01

    Ability to visualize breast lesion vascularity and quantify the vascular heterogeneity using contrast-enhanced 3-D harmonic (HI) and subharmonic (SHI) ultrasound imaging was investigated in a clinical population. Patients (n = 134) identified with breast lesions on mammography were scanned using power Doppler imaging, contrast-enhanced 3-D HI, and 3-D SHI on a modified Logiq 9 scanner (GE Healthcare). A region of interest corresponding to ultrasound contrast agent flow was identified in 4D View (GE Medical Systems) and mapped to raw slice data to generate a map of time-intensity curves for the lesion volume. Time points corresponding to baseline, peak intensity, and washout of ultrasound contrast agent were identified and used to generate and compare vascular heterogeneity plots for malignant and benign lesions. Vascularity was observed with power Doppler imaging in 84 lesions (63 benign and 21 malignant). The 3-D HI showed flow in 8 lesions (5 benign and 3 malignant), whereas 3-D SHI visualized flow in 68 lesions (49 benign and 19 malignant). Analysis of vascular heterogeneity in the 3-D SHI volumes found benign lesions having a significant difference in vascularity between central and peripheral sections (1.71 ± 0.96 vs. 1.13 ± 0.79 dB, p < 0.001, respectively), whereas malignant lesions showed no difference (1.66 ± 1.39 vs. 1.24 ± 1.14 dB, p = 0.24), indicative of more vascular coverage. These preliminary results suggest quantitative evaluation of vascular heterogeneity in breast lesions using contrast-enhanced 3-D SHI is feasible and able to detect variations in vascularity between central and peripheral sections for benign and malignant lesions. PMID:25935933

  14. Quantitative analysis of vascular heterogeneity in breast lesions using contrast-enhanced 3-D harmonic and subharmonic ultrasound imaging.

    PubMed

    Sridharan, Anush; Eisenbrey, John R; Machado, Priscilla; Ojeda-Fournier, Haydee; Wilkes, Annina; Sevrukov, Alexander; Mattrey, Robert F; Wallace, Kirk; Chalek, Carl L; Thomenius, Kai E; Forsberg, Flemming

    2015-03-01

    Ability to visualize breast lesion vascularity and quantify the vascular heterogeneity using contrast-enhanced 3-D harmonic (HI) and subharmonic (SHI) ultrasound imaging was investigated in a clinical population. Patients (n = 134) identified with breast lesions on mammography were scanned using power Doppler imaging, contrast-enhanced 3-D HI, and 3-D SHI on a modified Logiq 9 scanner (GE Healthcare). A region of interest corresponding to ultrasound contrast agent flow was identified in 4D View (GE Medical Systems) and mapped to raw slice data to generate a map of time-intensity curves for the lesion volume. Time points corresponding to baseline, peak intensity, and washout of ultrasound contrast agent were identified and used to generate and compare vascular heterogeneity plots for malignant and benign lesions. Vascularity was observed with power Doppler imaging in 84 lesions (63 benign and 21 malignant). The 3-D HI showed flow in 8 lesions (5 benign and 3 malignant), whereas 3-D SHI visualized flow in 68 lesions (49 benign and 19 malignant). Analysis of vascular heterogeneity in the 3-D SHI volumes found benign lesions having a significant difference in vascularity between central and peripheral sections (1.71 ± 0.96 vs. 1.13 ± 0.79 dB, p < 0.001, respectively), whereas malignant lesions showed no difference (1.66 ± 1.39 vs. 1.24 ± 1.14 dB, p = 0.24), indicative of more vascular coverage. These preliminary results suggest quantitative evaluation of vascular heterogeneity in breast lesions using contrast-enhanced 3-D SHI is feasible and able to detect variations in vascularity between central and peripheral sections for benign and malignant lesions.

  15. 3D microscopy - new powerful tools in geomaterials characterization

    NASA Astrophysics Data System (ADS)

    Mauko Pranjić, Alenka; Mladenovič, Ana; Turk, Janez; Šajna, Aljoša; Čretnik, Janko

    2016-04-01

    Microtomography (microCT) is becoming more and more widely recognized in geological sciences as a powerful tool for the spatial characterization of rock and other geological materials. Together with 3D image analysis and other complementary techniques, it has the characteristics of an innovative and non-destructive 3D microscopical technique. On the other hand its main disadvantages are low availability (only a few geological laboratories are equipped with high resolution tomographs), the relatively high prices of testing connected with the use of an xray source, technical limitations connected to the resolution and imaging of certain materials, as well as timeconsuming and complex 3D image analysis, necessary for quantification of 3D tomographic data sets. In this work three examples are presented of optimal 3D microscopy analysis of geomaterials in construction such as porosity characterization of impregnated sandstone, aerated concrete and marble prone to bowing. Studies include processes of microCT imaging, 3D data analysis and fitting of data with complementary analysis, such as confocal microscopy, mercury porosimetry, gas sorption, optical/fluorescent microscopy and scanning electron microscopy. Present work has been done in the frame of national research project 3D and 4D microscopy development of new powerful tools in geosciences (ARRS J1-7148) funded by Slovenian Research Agency.

  16. 3D texture analysis for classification of second harmonic generation images of human ovarian cancer

    PubMed Central

    Wen, Bruce; Campbell, Kirby R.; Tilbury, Karissa; Nadiarnykh, Oleg; Brewer, Molly A.; Patankar, Manish; Singh, Vikas; Eliceiri, Kevin. W.; Campagnola, Paul J.

    2016-01-01

    Remodeling of the collagen architecture in the extracellular matrix (ECM) has been implicated in ovarian cancer. To quantify these alterations we implemented a form of 3D texture analysis to delineate the fibrillar morphology observed in 3D Second Harmonic Generation (SHG) microscopy image data of normal (1) and high risk (2) ovarian stroma, benign ovarian tumors (3), low grade (4) and high grade (5) serous tumors, and endometrioid tumors (6). We developed a tailored set of 3D filters which extract textural features in the 3D image sets to build (or learn) statistical models of each tissue class. By applying k-nearest neighbor classification using these learned models, we achieved 83–91% accuracies for the six classes. The 3D method outperformed the analogous 2D classification on the same tissues, where we suggest this is due the increased information content. This classification based on ECM structural changes will complement conventional classification based on genetic profiles and can serve as an additional biomarker. Moreover, the texture analysis algorithm is quite general, as it does not rely on single morphological metrics such as fiber alignment, length, and width but their combined convolution with a customizable basis set. PMID:27767180

  17. 3D texture analysis for classification of second harmonic generation images of human ovarian cancer

    NASA Astrophysics Data System (ADS)

    Wen, Bruce; Campbell, Kirby R.; Tilbury, Karissa; Nadiarnykh, Oleg; Brewer, Molly A.; Patankar, Manish; Singh, Vikas; Eliceiri, Kevin. W.; Campagnola, Paul J.

    2016-10-01

    Remodeling of the collagen architecture in the extracellular matrix (ECM) has been implicated in ovarian cancer. To quantify these alterations we implemented a form of 3D texture analysis to delineate the fibrillar morphology observed in 3D Second Harmonic Generation (SHG) microscopy image data of normal (1) and high risk (2) ovarian stroma, benign ovarian tumors (3), low grade (4) and high grade (5) serous tumors, and endometrioid tumors (6). We developed a tailored set of 3D filters which extract textural features in the 3D image sets to build (or learn) statistical models of each tissue class. By applying k-nearest neighbor classification using these learned models, we achieved 83–91% accuracies for the six classes. The 3D method outperformed the analogous 2D classification on the same tissues, where we suggest this is due the increased information content. This classification based on ECM structural changes will complement conventional classification based on genetic profiles and can serve as an additional biomarker. Moreover, the texture analysis algorithm is quite general, as it does not rely on single morphological metrics such as fiber alignment, length, and width but their combined convolution with a customizable basis set.

  18. A harmonic polynomial cell (HPC) method for 3D Laplace equation with application in marine hydrodynamics

    SciTech Connect

    Shao, Yan-Lin Faltinsen, Odd M.

    2014-10-01

    We propose a new efficient and accurate numerical method based on harmonic polynomials to solve boundary value problems governed by 3D Laplace equation. The computational domain is discretized by overlapping cells. Within each cell, the velocity potential is represented by the linear superposition of a complete set of harmonic polynomials, which are the elementary solutions of Laplace equation. By its definition, the method is named as Harmonic Polynomial Cell (HPC) method. The characteristics of the accuracy and efficiency of the HPC method are demonstrated by studying analytical cases. Comparisons will be made with some other existing boundary element based methods, e.g. Quadratic Boundary Element Method (QBEM) and the Fast Multipole Accelerated QBEM (FMA-QBEM) and a fourth order Finite Difference Method (FDM). To demonstrate the applications of the method, it is applied to some studies relevant for marine hydrodynamics. Sloshing in 3D rectangular tanks, a fully-nonlinear numerical wave tank, fully-nonlinear wave focusing on a semi-circular shoal, and the nonlinear wave diffraction of a bottom-mounted cylinder in regular waves are studied. The comparisons with the experimental results and other numerical results are all in satisfactory agreement, indicating that the present HPC method is a promising method in solving potential-flow problems. The underlying procedure of the HPC method could also be useful in other fields than marine hydrodynamics involved with solving Laplace equation.

  19. Exact spectra of strong coulomb correlations of 3-D 2-e harmonic dots in magnetic field

    NASA Astrophysics Data System (ADS)

    Aggarwal, Priyanka; Sharma, Shivalika; Kaur, Harsimran; Singh, Sunny; Hazra, Ram Kuntal

    2017-01-01

    Applications of 3-D 2-e systems have proliferated very fast due to technological advancements in wide range of phenomena from atomic landscape to mesoscopic scale. The unusual properties of atomic/mesoscopic systems are the results of interplaying charge interactions among different bound states. The non-trivial e-e correlations in electrically and/or magnetically confined systems improvise wealth of intriguing challenges at fundamental level due to lack of exact solution of Schrödinger equations. For the first time, a novel methodology of exactly finite summed coulomb correlations invented by us is so handy that even usual programmable calculator can be used to examine the electronic structures of 3-D 2-e harmonic dots in perpendicular magnetic field (symmetric gauge). Statistics of electronic levels, heat capacity measurements and magnetization (T∼1 K) are also investigated in brief to probe the degree of disorderedness.

  20. An inverse hyper-spherical harmonics-based formulation for reconstructing 3D volumetric lung deformations

    NASA Astrophysics Data System (ADS)

    Santhanam, Anand P.; Min, Yugang; Mudur, Sudhir P.; Rastogi, Abhinav; Ruddy, Bari H.; Shah, Amish; Divo, Eduardo; Kassab, Alain; Rolland, Jannick P.; Kupelian, Patrick

    2010-07-01

    A method to estimate the deformation operator for the 3D volumetric lung dynamics of human subjects is described in this paper. For known values of air flow and volumetric displacement, the deformation operator and subsequently the elastic properties of the lung are estimated in terms of a Green's function. A Hyper-Spherical Harmonic (HSH) transformation is employed to compute the deformation operator. The hyper-spherical coordinate transformation method discussed in this paper facilitates accounting for the heterogeneity of the deformation operator using a finite number of frequency coefficients. Spirometry measurements are used to provide values for the airflow inside the lung. Using a 3D optical flow-based method, the 3D volumetric displacement of the left and right lungs, which represents the local anatomy and deformation of a human subject, was estimated from 4D-CT dataset. Results from an implementation of the method show the estimation of the deformation operator for the left and right lungs of a human subject with non-small cell lung cancer. Validation of the proposed method shows that we can estimate the Young's modulus of each voxel within a 2% error level.

  1. High Power Amplifier Harmonic Output Level Measurement

    NASA Technical Reports Server (NTRS)

    Perez, R. M.; Hoppe, D. J.; Khan, A. R.

    1995-01-01

    A method is presented for the measurement of the harmonic output power of high power klystron amplifiers, involving coherent hemispherical radiation pattern measurements of the radiated klystron output. Results are discussed for the operation in saturated and unsaturated conditions, and with a waveguide harmonic filter included.

  2. Breast tumor angiogenesis analysis using 3D power Doppler ultrasound

    NASA Astrophysics Data System (ADS)

    Chang, Ruey-Feng; Huang, Sheng-Fang; Lee, Yu-Hau; Chen, Dar-Ren; Moon, Woo Kyung

    2006-03-01

    Angiogenesis is the process that correlates to tumor growth, invasion, and metastasis. Breast cancer angiogenesis has been the most extensively studied and now serves as a paradigm for understanding the biology of angiogenesis and its effects on tumor outcome and patient prognosis. Most studies on characterization of angiogenesis focus on pixel/voxel counts more than morphological analysis. Nevertheless, in cancer, the blood flow is greatly affected by the morphological changes, such as the number of vessels, branching pattern, length, and diameter. This paper presents a computer-aided diagnostic (CAD) system that can quantify vascular morphology using 3-D power Doppler ultrasound (US) on breast tumors. We propose a scheme to extract the morphological information from angiography and to relate them to tumor diagnosis outcome. At first, a 3-D thinning algorithm helps narrow down the vessels into their skeletons. The measurements of vascular morphology significantly rely on the traversing of the vascular trees produced from skeletons. Our study of 3-D assessment of vascular morphological features regards vessel count, length, bifurcation, and diameter of vessels. Investigations into 221 solid breast tumors including 110 benign and 111 malignant cases, the p values using the Student's t-test for all features are less than 0.05 indicating that the proposed features are deemed statistically significant. Our scheme focuses on the vascular architecture without involving the technique of tumor segmentation. The results show that the proposed method is feasible, and have a good agreement with the diagnosis of the pathologists.

  3. Unbiased contaminant removal for 3D galaxy power spectrum measurements

    NASA Astrophysics Data System (ADS)

    Kalus, B.; Percival, W. J.; Bacon, D. J.; Samushia, L.

    2016-11-01

    We assess and develop techniques to remove contaminants when calculating the 3D galaxy power spectrum. We separate the process into three separate stages: (i) removing the contaminant signal, (ii) estimating the uncontaminated cosmological power spectrum and (iii) debiasing the resulting estimates. For (i), we show that removing the best-fitting contaminant (mode subtraction) and setting the contaminated components of the covariance to be infinite (mode deprojection) are mathematically equivalent. For (ii), performing a quadratic maximum likelihood (QML) estimate after mode deprojection gives an optimal unbiased solution, although it requires the manipulation of large N_mode^2 matrices (Nmode being the total number of modes), which is unfeasible for recent 3D galaxy surveys. Measuring a binned average of the modes for (ii) as proposed by Feldman, Kaiser & Peacock (FKP) is faster and simpler, but is sub-optimal and gives rise to a biased solution. We present a method to debias the resulting FKP measurements that does not require any large matrix calculations. We argue that the sub-optimality of the FKP estimator compared with the QML estimator, caused by contaminants, is less severe than that commonly ignored due to the survey window.

  4. Bound state solution of Dirac equation for 3D harmonics oscillator plus trigonometric scarf noncentral potential using SUSY QM approach

    SciTech Connect

    Cari, C. Suparmi, A.

    2014-09-30

    Dirac equation of 3D harmonics oscillator plus trigonometric Scarf non-central potential for spin symmetric case is solved using supersymmetric quantum mechanics approach. The Dirac equation for exact spin symmetry reduces to Schrodinger like equation. The relativistic energy and wave function for spin symmetric case are simply obtained using SUSY quantum mechanics method and idea of shape invariance.

  5. Power Factor Correction to Mitigate Harmonic Distortion

    NASA Astrophysics Data System (ADS)

    Kochetkov, Gary

    Many direct current (DC) devices must receive their power from the alternating current (AC) grid. Rectifiers use diodes to create DC for these devices. Due to diodes' non-linear nature however, harmonics are created and these travel back into the grid. A significant presence of harmonics causes component heating and possible malfunction. A harmonic mitigation procedure is needed. With the correct usage of transistors, the current drawn by a rectifier can be manipulated to remove almost all harmonics. This process is called power factor correction (PFC), and formally acts to reduce the total harmonic distortion (THD) of the current. To investigate this, a three phase active rectifier was computer simulated and a controller was designed to provide switching signals for the transistors. Finally, the device was constructed in the laboratory to drive a DC motor, verifying its operating principle outside of the idealities of simulation.

  6. Efficient Second Harmonic Generation in 3D Nonlinear Optical-Lattice-Like Cladding Waveguide Splitters by Femtosecond Laser Inscription

    NASA Astrophysics Data System (ADS)

    Nie, Weijie; Jia, Yuechen; Vázquez de Aldana, Javier R.; Chen, Feng

    2016-02-01

    Integrated photonic devices with beam splitting function are intriguing for a broad range of photonic applications. Through optical-lattice-like cladding waveguide structures fabricated by direct femtosecond laser writing, the light propagation can be engineered via the track-confined refractive index profiles, achieving tailored output beam distributions. In this work, we report on the fabrication of 3D laser-written optical-lattice-like structures in a nonlinear KTP crystal to implement 1 × 4 beam splitting. Second harmonic generation (SHG) of green light through these nonlinear waveguide beam splitter structures provides the capability for the compact visible laser emitting devices. With Type II phase matching of the fundamental wavelength (@ 1064 nm) to second harmonic waves (@ 532 nm), the frequency doubling has been achieved through this three-dimensional beam splitter. Under 1064-nm continuous-wave fundamental-wavelength pump beam, guided-wave SHG at 532 nm are measured with the maximum power of 0.65 mW and 0.48 mW for waveguide splitters (0.67 mW and 0.51 mW for corresponding straight channel waveguides), corresponding to a SH conversion efficiency of approximately ~14.3%/W and 13.9%/W (11.2%/W, 11.3%/W for corresponding straight channel waveguides), respectively. This work paves a way to fabricate compact integrated nonlinear photonic devices in a single chip with beam dividing functions.

  7. Efficient Second Harmonic Generation in 3D Nonlinear Optical-Lattice-Like Cladding Waveguide Splitters by Femtosecond Laser Inscription

    PubMed Central

    Nie, Weijie; Jia, Yuechen; Vázquez de Aldana, Javier R.; Chen, Feng

    2016-01-01

    Integrated photonic devices with beam splitting function are intriguing for a broad range of photonic applications. Through optical-lattice-like cladding waveguide structures fabricated by direct femtosecond laser writing, the light propagation can be engineered via the track-confined refractive index profiles, achieving tailored output beam distributions. In this work, we report on the fabrication of 3D laser-written optical-lattice-like structures in a nonlinear KTP crystal to implement 1 × 4 beam splitting. Second harmonic generation (SHG) of green light through these nonlinear waveguide beam splitter structures provides the capability for the compact visible laser emitting devices. With Type II phase matching of the fundamental wavelength (@ 1064 nm) to second harmonic waves (@ 532 nm), the frequency doubling has been achieved through this three-dimensional beam splitter. Under 1064-nm continuous-wave fundamental-wavelength pump beam, guided-wave SHG at 532 nm are measured with the maximum power of 0.65 mW and 0.48 mW for waveguide splitters (0.67 mW and 0.51 mW for corresponding straight channel waveguides), corresponding to a SH conversion efficiency of approximately ~14.3%/W and 13.9%/W (11.2%/W, 11.3%/W for corresponding straight channel waveguides), respectively. This work paves a way to fabricate compact integrated nonlinear photonic devices in a single chip with beam dividing functions. PMID:26924255

  8. Efficient Second Harmonic Generation in 3D Nonlinear Optical-Lattice-Like Cladding Waveguide Splitters by Femtosecond Laser Inscription.

    PubMed

    Nie, Weijie; Jia, Yuechen; Vázquez de Aldana, Javier R; Chen, Feng

    2016-02-29

    Integrated photonic devices with beam splitting function are intriguing for a broad range of photonic applications. Through optical-lattice-like cladding waveguide structures fabricated by direct femtosecond laser writing, the light propagation can be engineered via the track-confined refractive index profiles, achieving tailored output beam distributions. In this work, we report on the fabrication of 3D laser-written optical-lattice-like structures in a nonlinear KTP crystal to implement 1 × 4 beam splitting. Second harmonic generation (SHG) of green light through these nonlinear waveguide beam splitter structures provides the capability for the compact visible laser emitting devices. With Type II phase matching of the fundamental wavelength (@ 1064 nm) to second harmonic waves (@ 532 nm), the frequency doubling has been achieved through this three-dimensional beam splitter. Under 1064-nm continuous-wave fundamental-wavelength pump beam, guided-wave SHG at 532 nm are measured with the maximum power of 0.65 mW and 0.48 mW for waveguide splitters (0.67 mW and 0.51 mW for corresponding straight channel waveguides), corresponding to a SH conversion efficiency of approximately ~14.3%/W and 13.9%/W (11.2%/W, 11.3%/W for corresponding straight channel waveguides), respectively. This work paves a way to fabricate compact integrated nonlinear photonic devices in a single chip with beam dividing functions.

  9. Power Divider for Harmonically Rich Waveforms

    NASA Technical Reports Server (NTRS)

    Sims, William Herbert, III (Inventor)

    2001-01-01

    A power divider divides an RF signal into two output signals having a phase difference of 180 deg. or a multiple thereof. When the RF signal is a square wave or another harmonically rich signal. the phases of the fundamental and the harmonics have the proper relationship. The divider can be implemented in the form of microstrips on a board, with one of the output microstrips having several bends to provide a different electrical length from the other.

  10. Harmonics in a Wind Power Plant: Preprint

    SciTech Connect

    Preciado, V.; Madrigal, M.; Muljadi, E.; Gevorgian, V.

    2015-04-02

    Wind power generation has been growing at a very fast pace for the past decade, and its influence and impact on the electric power grid is significant. As in a conventional power plant, a wind power plant (WPP) must ensure that the quality of the power being delivered to the grid is excellent. At the same time, the wind turbine should be able to operate immune to small disturbances coming from the grid. Harmonics are one of the more common power quality issues presented by large WPPs because of the high switching frequency of the power converters and the possible nonlinear behavior from electric machines (generator, transformer, reactors) within a power plant. This paper presents a summary of the most important issues related to harmonics in WPPs and discusses practical experiences with actual Type 1 and Type 3 wind turbines in two WPPs.

  11. Power Divider for Waveforms Rich in Harmonics

    NASA Technical Reports Server (NTRS)

    Sims, William Herbert, III

    2005-01-01

    A method for dividing the power of an electronic signal rich in harmonics involves the use of an improved divider topology. A divider designed with this topology could be used, for example, to propagate a square-wave signal in an amplifier designed with a push-pull configuration to enable the generation of more power than could be generated in another configuration.

  12. Power System Harmonic Elimination to Improve Power Quality

    NASA Astrophysics Data System (ADS)

    Chandrasekaran, K.; Ramachandaramurthy, V. K.

    2015-06-01

    An improvised RLC interface filter for a Dynamic Voltage Restorer (DVR) is proposed. The RLC filter is connected in the front end between the IGBT based Voltage Source Inverter (VSI) and the injection transformer and is able to eliminate voltage harmonics in the system and also switching harmonics generated from VSI. The voltage at the sensitive load end is pure sinusoidal. In this method, the DVR produced Pulse Width Modulation (PWM) voltage with voltage harmonic canceling the voltage harmonic generated from the supply main. The VSI handles harmonic power. The low order switching harmonics generated by the IGBT based VSI is suppressed. The DVR has greater voltage injection capability. Good dynamic and transient results recorded and Total Harmonic Distortion (THD) at the sensitive load end is minimized. The voltage at the sensitive load is sinusoidal and at 1.0 pu. PSCAD/EMTDC is used to validate the performance of the interface filter and the DVR. Simulated results are presented.

  13. Tomographic reconstruction of circularly polarized high-harmonic fields: 3D attosecond metrology.

    PubMed

    Chen, Cong; Tao, Zhensheng; Hernández-García, Carlos; Matyba, Piotr; Carr, Adra; Knut, Ronny; Kfir, Ofer; Zusin, Dimitry; Gentry, Christian; Grychtol, Patrik; Cohen, Oren; Plaja, Luis; Becker, Andreas; Jaron-Becker, Agnieszka; Kapteyn, Henry; Murnane, Margaret

    2016-02-01

    Bright, circularly polarized, extreme ultraviolet (EUV) and soft x-ray high-harmonic beams can now be produced using counter-rotating circularly polarized driving laser fields. Although the resulting circularly polarized harmonics consist of relatively simple pairs of peaks in the spectral domain, in the time domain, the field is predicted to emerge as a complex series of rotating linearly polarized bursts, varying rapidly in amplitude, frequency, and polarization. We extend attosecond metrology techniques to circularly polarized light by simultaneously irradiating a copper surface with circularly polarized high-harmonic and linearly polarized infrared laser fields. The resulting temporal modulation of the photoelectron spectra carries essential phase information about the EUV field. Utilizing the polarization selectivity of the solid surface and by rotating the circularly polarized EUV field in space, we fully retrieve the amplitude and phase of the circularly polarized harmonics, allowing us to reconstruct one of the most complex coherent light fields produced to date.

  14. Tomographic reconstruction of circularly polarized high-harmonic fields: 3D attosecond metrology

    PubMed Central

    Chen, Cong; Tao, Zhensheng; Hernández-García, Carlos; Matyba, Piotr; Carr, Adra; Knut, Ronny; Kfir, Ofer; Zusin, Dimitry; Gentry, Christian; Grychtol, Patrik; Cohen, Oren; Plaja, Luis; Becker, Andreas; Jaron-Becker, Agnieszka; Kapteyn, Henry; Murnane, Margaret

    2016-01-01

    Bright, circularly polarized, extreme ultraviolet (EUV) and soft x-ray high-harmonic beams can now be produced using counter-rotating circularly polarized driving laser fields. Although the resulting circularly polarized harmonics consist of relatively simple pairs of peaks in the spectral domain, in the time domain, the field is predicted to emerge as a complex series of rotating linearly polarized bursts, varying rapidly in amplitude, frequency, and polarization. We extend attosecond metrology techniques to circularly polarized light by simultaneously irradiating a copper surface with circularly polarized high-harmonic and linearly polarized infrared laser fields. The resulting temporal modulation of the photoelectron spectra carries essential phase information about the EUV field. Utilizing the polarization selectivity of the solid surface and by rotating the circularly polarized EUV field in space, we fully retrieve the amplitude and phase of the circularly polarized harmonics, allowing us to reconstruct one of the most complex coherent light fields produced to date. PMID:26989782

  15. Exterior 3D lamb problem: Harmonic load distributed over a surface

    NASA Astrophysics Data System (ADS)

    Il'yasov, Kh. Kh.; Kravtsov, A. V.; Kuznetsov, S. V.; Sekerzh-Zen'kovich, S. Ya.

    2016-06-01

    The solutions of the exterior Lamb problem with a distributed harmonic surface load acting on the boundary of an elastic half-space are studied. A load normal to the surface and distributed over the surface as the Poisson kernel is considered. The solution is constructed with the use of integral transforms and the finite-element method.

  16. Novel 3D bismuth-based coordination polymers: Synthesis, structure, and second harmonic generation properties

    NASA Astrophysics Data System (ADS)

    Wibowo, Arief C.; Smith, Mark D.; Yeon, Jeongho; Halasyamani, P. Shiv; zur Loye, Hans-Conrad

    2012-11-01

    Two new 3D bismuth containing coordination polymers are reported along with their single crystal structures and SHG properties. Compound 1: Bi2O2(pydc) (pydc=pyridine-2, 5-dicarboxylate), crystallizes in the monoclinic, polar space group, P21 (a=9.6479(9) Å, b=4.2349(4) Å, c=11.9615(11) Å, β=109.587(1)°), which contains Bi2O2 chains that are connected into a 3D structure via the pydc ligands. Compound 2: Bi4Na4(1R3S-cam)8(EtOH)3.1(H2O)3.4 (1R3S cam=1R3S-camphoric acid) crystallizes in the monoclinic, polar space group, P21 (a=19.0855(7) Å, b=13.7706(5) Å, c=19.2429(7) Å, β=90.701(1)°) and is a true 3D coordination polymer. These are two example of SHG compounds prepared using unsymmetric ligands (compound 1) or chiral ligands (compound 2), together with metals that often exhibit stereochemically-active lone pairs, such as Bi3+, a synthetic approach that resulted in polar, non-centrosymmetric, 3D metal-organic coordination polymer.

  17. Novel 3D bismuth-based coordination polymers: Synthesis, structure, and second harmonic generation properties

    SciTech Connect

    Wibowo, Arief C.; Smith, Mark D.; Yeon, Jeongho; Halasyamani, P. Shiv; Loye, Hans-Conrad zur

    2012-11-15

    Two new 3D bismuth containing coordination polymers are reported along with their single crystal structures and SHG properties. Compound 1: Bi{sub 2}O{sub 2}(pydc) (pydc=pyridine-2, 5-dicarboxylate), crystallizes in the monoclinic, polar space group, P2{sub 1} (a=9.6479(9) A, b=4.2349(4) A, c=11.9615(11) A, {beta}=109.587(1) Degree-Sign ), which contains Bi{sub 2}O{sub 2} chains that are connected into a 3D structure via the pydc ligands. Compound 2: Bi{sub 4}Na{sub 4}(1R3S-cam){sub 8}(EtOH){sub 3.1}(H{sub 2}O){sub 3.4} (1R3S cam=1R3S-camphoric acid) crystallizes in the monoclinic, polar space group, P2{sub 1} (a=19.0855(7) A, b=13.7706(5) A, c=19.2429(7) A, {beta}=90.701(1) Degree-Sign ) and is a true 3D coordination polymer. These are two example of SHG compounds prepared using unsymmetric ligands (compound 1) or chiral ligands (compound 2), together with metals that often exhibit stereochemically-active lone pairs, such as Bi{sup 3+}, a synthetic approach that resulted in polar, non-centrosymmetric, 3D metal-organic coordination polymer. - Graphical Abstract: Structures of two new, polar, 3D Bismuth(III)-based coordination polymers: Bi{sub 2}O{sub 2}(pydc) (compound 1), and Bi{sub 4}Na{sub 4}(1R3S-cam){sub 8}(EtOH){sub 3.1}(H{sub 2}O){sub 3.4} (compound 2). Highlights: Black-Right-Pointing-Pointer New, polar, 3D Bismuth(III)-based coordination polymers. Black-Right-Pointing-Pointer First polar bismuth-based coordination polymers synthesized via a 'hybrid' strategy. Black-Right-Pointing-Pointer Combination of stereochemically-active lone pairs and unsymmetrical or chiral ligands. Black-Right-Pointing-Pointer Synthesis of class C-SHG materials based on Kurtz-Perry categories.

  18. A 3D-printed high power nuclear spin polarizer.

    PubMed

    Nikolaou, Panayiotis; Coffey, Aaron M; Walkup, Laura L; Gust, Brogan M; LaPierre, Cristen D; Koehnemann, Edward; Barlow, Michael J; Rosen, Matthew S; Goodson, Boyd M; Chekmenev, Eduard Y

    2014-01-29

    Three-dimensional printing with high-temperature plastic is used to enable spin exchange optical pumping (SEOP) and hyperpolarization of xenon-129 gas. The use of 3D printed structures increases the simplicity of integration of the following key components with a variable temperature SEOP probe: (i) in situ NMR circuit operating at 84 kHz (Larmor frequencies of (129)Xe and (1)H nuclear spins), (ii) <0.3 nm narrowed 200 W laser source, (iii) in situ high-resolution near-IR spectroscopy, (iv) thermoelectric temperature control, (v) retroreflection optics, and (vi) optomechanical alignment system. The rapid prototyping endowed by 3D printing dramatically reduces production time and expenses while allowing reproducibility and integration of "off-the-shelf" components and enables the concept of printing on demand. The utility of this SEOP setup is demonstrated here to obtain near-unity (129)Xe polarization values in a 0.5 L optical pumping cell, including ∼74 ± 7% at 1000 Torr xenon partial pressure, a record value at such high Xe density. Values for the (129)Xe polarization exponential build-up rate [(3.63 ± 0.15) × 10(-2) min(-1)] and in-cell (129)Xe spin-lattice relaxation time (T1 = 2.19 ± 0.06 h) for 1000 Torr Xe were in excellent agreement with the ratio of the gas-phase polarizations for (129)Xe and Rb (PRb ∼ 96%). Hyperpolarization-enhanced (129)Xe gas imaging was demonstrated with a spherical phantom following automated gas transfer from the polarizer. Taken together, these results support the development of a wide range of chemical, biochemical, material science, and biomedical applications.

  19. A 3D-Printed High Power Nuclear Spin Polarizer

    PubMed Central

    Nikolaou, Panayiotis; Coffey, Aaron M.; Walkup, Laura L.; Gust, Brogan M.; LaPierre, Cristen D.; Koehnemann, Edward; Barlow, Michael J.; Rosen, Matthew S.; Goodson, Boyd M.; Chekmenev, Eduard Y.

    2015-01-01

    Three-dimensional printing with high-temperature plastic is used to enable spin exchange optical pumping (SEOP) and hyperpolarization of xenon-129 gas. The use of 3D printed structures increases the simplicity of integration of the following key components with a variable temperature SEOP probe: (i) in situ NMR circuit operating at 84 kHz (Larmor frequencies of 129Xe and 1H nuclear spins), (ii) <0.3 nm narrowed 200 W laser source, (iii) in situ high-resolution near-IR spectroscopy, (iv) thermoelectric temperature control, (v) retroreflection optics, and (vi) optomechanical alignment system. The rapid prototyping endowed by 3D printing dramatically reduces production time and expenses while allowing reproducibility and integration of “off-the-shelf” components and enables the concept of printing on demand. The utility of this SEOP setup is demonstrated here to obtain near-unity 129Xe polarization values in a 0.5 L optical pumping cell, including ~74 ± 7% at 1000 Torr xenon partial pressure, a record value at such high Xe density. Values for the 129Xe polarization exponential build-up rate [(3.63 ± 0.15) × 10−2 min−1] and in-cell 129Xe spin−lattice relaxation time (T1 = 2.19 ± 0.06 h) for 1000 Torr Xe were in excellent agreement with the ratio of the gas-phase polarizations for 129Xe and Rb (PRb ~ 96%). Hyperpolarization-enhanced 129Xe gas imaging was demonstrated with a spherical phantom following automated gas transfer from the polarizer. Taken together, these results support the development of a wide range of chemical, biochemical, material science, and biomedical applications. PMID:24400919

  20. Study on the Before Cavity Interaction in a Second Harmonic Gyrotron Using 3D CFDTD PIC Simulations

    NASA Astrophysics Data System (ADS)

    Lin, M. C.; Illy, S.; Thumm, M.; Jelonnek, J.

    2016-10-01

    A computational study on before cavity interaction (BCI) in a 28 GHz second harmonic (SH) gryotron for industrial applications has been performed using a 3-D conformal finite-difference time-domain (CFDTD) particle-in-cell (PIC) method. On the contrary to the after cavity interaction (ACI), i.e. beam wave interaction in the non-linear uptaper after the cavity, which has been widely investigated, the BCI, i.e. beam wave interaction in the non-linear downtaper before the cavity connected to the beam tunnel with an entrance, is less noticed and discussed. Usually the BCI might be considered easy to be eliminated. However, this is not always the case. As the SH gyrotron had been designed for SH TE12 mode operation, the first harmonic (FH) plays the main competition. In the 3-D CFDTD PIC simulations, a port boundary has been employed for the gyro-beam entrance of the gyrotron cavity instead of a metallic short one which is not reflecting a realistic situation as an FH backward wave oscillation (BWO) is competing with the desired SH generation. A numerical instability has been found and identified as a failure of the entrance port boundary caused by an evanescent wave or mode conversion. This indicates the entrance and downtaper are not fully cut-off for some oscillations. A further study shows that the undesired oscillation is the FH TE11 BWO mode concentrated around the beam tunnel entrance and downtaper. A mitigation strategy has been found to suppress this undesired BCI and avoid possible damage to the gun region.

  1. Parameter analysis for a high-gain harmonic generation FEL using a recently developed 3D polychromatic code.

    SciTech Connect

    Biedron, S. G.; Freund, H. P.; Yu, L.-H.

    1999-09-10

    One possible design for a fourth-generation light source is the high-gain harmonic generation (HGHG) free-electron laser (FEL). Here, a coherent seed with a wavelength at a subharmonic of the desired output radiation interacts with the electron beam in an energy-modulating section. This energy modulation is then converted into spatial bunching while traversing a dispersive section (a three-dipole chicane). The final step is passage through a radiative section, an undulator tuned to the desired higher harmonic output wavelength. The coherent seed serves to remove noise and can be at a much lower subharmonic of the output radiation, thus eliminating the concerns found in self-amplified spontaneous emission (SASE) and seeded FELs, respectively. Recently, a 3D code that includes multiple frequencies, multiple undulatory (both in quantity and/or type), quadruple magnets, and dipole magnets was developed to easily simulate HGHG. Here, a brief review of the HGHG theory, the code development, the Accelerator Test Facility's (ATF) HGHG FEL experimental parameters, and the parameter analysis from simulations of this specific experiment will be discussed.

  2. Generation mechanism of power line harmonic radiation

    NASA Astrophysics Data System (ADS)

    Kostrov, Alexander; Gushchin, Mikhail; Korobkov, Sergei

    The questions concerning the generation of power line harmonic radiation (PLHR) and magne-tospheric line radiation (MLR) are discussed, including the effective source of high harmonics of 50/60 Hz, and fine dynamic structure of the frequency spectrum of PLHR and MLR. It is shown, that thyristor-based power regulators used by large electrical power consumers produce the periodic sequences of current pulses with duration of about 10 microseconds in a power line. The repetition rate of these pulses is typically 100/120 Hz; the bandwidth is as broad as 100 kHz. For high harmonics of 50/60 Hz, the power line represents an effective traveling-wave (or Beverage) antenna, especially in a frequency range of several kHz corresponding to VLF whistler band in Earth ionosphere and magnetosphere. For the fixed length of the power line, which acts as antenna, radiation directivity diagram in relation to horizon depends of frequency. Hence the spatial separation of whistlers emitted at various frequencies (1-10 kHz in a consid-ered case) is possible, with subsequent propagation of whistlers with different frequencies along different L-shells. Estimations show that the efficiency of power line as travelling-wave antenna can be changed by variations of its load, but not more than twice ("weekend effect"). Since the PLHR can represent the sequence of short electromagnetic bursts, then careful se-lection of frequency-time resolution of the data acquisition equipment is needed. Typically, the time constant of the data recording and processing is too large, and the spectra of PLHR or MLR are characterized by a well-known line structure. At the same time, original bursty structure of PLHR can not be defined. Fine structure of MLR is also discussed. Frequency drift of MLR can be explained by the perturbations of the magnetospheric plasma by intense ULF waves and particle flows affecting the propagation of PLHR. Hence the physical nature of PLHR and MLR is the same, excepting the

  3. Research on the Dynamic Problems of 3D Cross Coupling Quantum Harmonic Oscillator by Virtue of Intermediate Representation | x> λ, ν

    NASA Astrophysics Data System (ADS)

    Xu, Shi-Min; Xu, Xing-Lei; Li, Hong-Qi

    2008-06-01

    The intermediate representation (namely intermediate coordinate-momentum representation) | x> λ, ν are introduced and employed to research the expression of the operator tauhat{p}+σhat{x} in intermediate representation | x> λ, ν . The systematic Hamilton operator hat{H} of 3D cross coupling quantum harmonic oscillator was diagonalized by virtue of quadratic form theory. The quantity of λ, ν, τand σ were figured out. The dynamic problems of 3D cross coupling quantum harmonic oscillator are researched by virtue of intermediate representation. The energy eigen-value and eigenwave function of 3D cross coupling quantum harmonic oscillator were obtained in intermediate representation. The importance of intermediate representation was discussed. The results show that the Radon transformation of Wigner operator is just the projectional operator | x> λ, ν λ, ν < x|, and the Radon transformation of Wigner function is just a margin distribution.

  4. To 3D or Not to 3D, That Is the Question: Do 3D Surface Analyses Improve the Ecomorphological Power of the Distal Femur in Placental Mammals?

    PubMed Central

    Gould, Francois D. H.

    2014-01-01

    Improvements in three-dimensional imaging technologies have renewed interest in the study of functional and ecological morphology. Quantitative approaches to shape analysis are used increasingly to study form-function relationships. These methods are computationally intensive, technically demanding, and time-consuming, which may limit sampling potential. There have been few side-by-side comparisons of the effectiveness of such approaches relative to more traditional analyses using linear measurements and ratios. Morphological variation in the distal femur of mammals has been shown to reflect differences in locomotor modes across clades. Thus I tested whether a geometric morphometric analysis of surface shape was superior to a multivariate analysis of ratios for describing ecomorphological patterns in distal femoral variation. A sample of 164 mammalian specimens from 44 genera was assembled. Each genus was assigned to one of six locomotor categories. The same hypotheses were tested using two methods. Six linear measurements of the distal femur were taken with calipers, from which four ratios were calculated. A 3D model was generated with a laser scanner, and analyzed using three dimensional geometric morphometrics. Locomotor category significantly predicted variation in distal femoral morphology in both analyses. Effect size was larger in the geometric morphometric analysis than in the analysis of ratios. Ordination reveals a similar pattern with arboreal and cursorial taxa as extremes on a continuum of morphologies in both analyses. Discriminant functions calculated from the geometric morphometric analysis were more accurate than those calculated from ratios. Both analysis of ratios and geometric morphometric surface analysis reveal similar, biologically meaningful relationships between distal femoral shape and locomotor mode. The functional signal from the morphology is slightly higher in the geometric morphometric analysis. The practical costs of conducting these

  5. 3D Modeling Activity for Novel High Power Electron Guns at SLAC

    SciTech Connect

    Krasnykh, Anatoly

    2003-07-29

    The next generation of powerful electronic devices requires new approaches to overcome the known limitations of existing tube technology. Multi-beam and sheet beam approaches are novel concepts for the high power microwave devices. Direct and indirect modeling methods are being developed at SLAC to meet the new requirements in the 3D modeling. The direct method of solving of Poisson's equations for the multi-beam and sheet beam guns is employed in the TOPAZ 3D tool. The combination of TOPAZ 2D and EGUN (in the beginning) with MAFIA 3D and MAGIC 3D (at the end) is used in an indirect method to model the high power electron guns. Both methods complement each other to get reliable representation of the beam trajectories. Several gun ideas are under consideration at the present time. The collected results of these simulations are discussed.

  6. Powering an in-space 3D printer using solar light energy

    NASA Astrophysics Data System (ADS)

    Leake, Skye; McGuire, Thomas; Parsons, Michael; Hirsch, Michael P.; Straub, Jeremy

    2016-05-01

    This paper describes how a solar power source can enable in-space 3D printing without requiring conversion to electric power and back. A design for an in-space 3D printer is presented, with a particular focus on the power generation system. Then, key benefits are presented and evaluated. Specifically, the approach facilitates the design of a spacecraft that can be built, launched, and operated at very low cost levels. The proposed approach also facilitates easy configuration of the amount of energy that is supplied. Finally, it facilitates easier disposal by removing the heavy metals and radioactive materials required for a nuclear-power solution.

  7. Harmonic analysis of spacecraft power systems using a personal computer

    NASA Technical Reports Server (NTRS)

    Williamson, Frank; Sheble, Gerald B.

    1989-01-01

    The effects that nonlinear devices such as ac/dc converters, HVDC transmission links, and motor drives have on spacecraft power systems are discussed. The nonsinusoidal currents, along with the corresponding voltages, are calculated by a harmonic power flow which decouples and solves for each harmonic component individually using an iterative Newton-Raphson algorithm. The sparsity of the harmonic equations and the overall Jacobian matrix is used to an advantage in terms of saving computer memory space and in terms of reducing computation time. The algorithm could also be modified to analyze each harmonic separately instead of all at the same time.

  8. Role of 3D power Doppler sonography in early prenatal diagnosis of Galen vein aneurysm

    PubMed Central

    Ergenoğlu, Mete Ahmet; Yeniel, Ahmet Özgür; Akdemir, Ali; Akercan, Fuat; Karadadaş, Nedim

    2013-01-01

    Vein of Galen aneurysm malformation (VGAM) is a rare congenital vascular anomaly. Although the cause of VGAM remains to be elucidated, the current hypothesis is persistence of the embryonic vascular supply, which leads to progressive enlargement and formation of the aneurysmal component of a typical VGAM. Here, we present a 36-year-old woman at 23 weeks’ gestation (gravida 3, para 2) who was evaluated using 3D power Doppler sonography for the prenatal diagnosis of a vein of Galen aneurysm. Investigation using 3D power Doppler sonography allowed for a non-invasive yet diffuse and detailed prenatal assessment of VGAM. Thus, we suggest that prenatal sonography with 3D power Doppler may be an option in cases of VGAM. PMID:24592100

  9. Satellite observations of power line harmonic radiation

    NASA Astrophysics Data System (ADS)

    Bullough, K.

    1983-06-01

    Observations of the spheric wavefield over North America, the adjacent North Atlantic, and their Southern-Hemisphere geomagnetic conjugates made with Ariel 4 are analyzed in terms of the relative influence of power-line harmonic radiation (PLHR) on wave-particle interactions affecting the earth's radiation belts. Inconsistencies in previous reports on the Sunday effect, on the starting frequencies of chorus emissions, and on the global distribution of PLHR are reviewed, and the validity of Ariel-3 and Ariel-4 findings of increased PLHR-induced emissions over the industrial areas of the US is asserted. At 9.6 kHz, the emissions over North America and the North Atlantic are characterized by almost identical spherical wavefields, while the whistler-mode signal in the Atlantic conjugate zone was found to be weaker than that in the North American conjugate; at 3.2 kHz, the sea-conjugate signal was weakened, but the land-conjugate signal was found to be identical to the land signal. It is inferred that multihop propagation permanently present over the mainland but rare over the sea is the result of duct structures which can be supported by PLHR.

  10. High average power second harmonic generation in air

    SciTech Connect

    Beresna, Martynas; Kazansky, Peter G.; Svirko, Yuri; Barkauskas, Martynas; Danielius, Romas

    2009-09-21

    We demonstrate second harmonic vortex generation in atmospheric pressure air using tightly focused femtosecond laser beam. The circularly polarized ring-shaped beam of the second harmonic is generated in the air by fundamental beam of the same circular polarization, while the linear polarized beam produces two-lobe beam at the second harmonic frequency. The achieved normalized conversion efficiency and average second harmonic power are two orders of magnitude higher compared to those previously reported and can be increased up to 20 times by external gas flow. We demonstrate that the frequency doubling originates from the gradient of photoexcited free electrons created by pondermotive force.

  11. A 3D Model of the Thermoelectric Microwave Power Sensor by MEMS Technology

    PubMed Central

    Yi, Zhenxiang; Liao, Xiaoping

    2016-01-01

    In this paper, a novel 3D model is proposed to describe the temperature distribution of the thermoelectric microwave power sensor. In this 3D model, the heat flux density decreases from the upper surface to the lower surface of the GaAs substrate while it was supposed to be a constant in the 2D model. The power sensor is fabricated by a GaAs monolithic microwave integrated circuit (MMIC) process and micro-electro-mechanical system (MEMS) technology. The microwave performance experiment shows that the S11 is less than −26 dB over the frequency band of 1–10 GHz. The power response experiment demonstrates that the output voltage increases from 0 mV to 27 mV, while the incident power varies from 1 mW to 100 mW. The measured sensitivity is about 0.27 mV/mW, and the calculated result from the 3D model is 0.28 mV/mW. The relative error has been reduced from 7.5% of the 2D model to 3.7% of the 3D model. PMID:27338395

  12. Efficient millimeter wave 1140 GHz/ diode for harmonic power generation

    NASA Technical Reports Server (NTRS)

    1967-01-01

    Epitaxial gallium arsenide diode junction formed in a crossed waveguide structure operates as a variable reactance harmonic generator. This varactor diode can generate power efficiently in the low-millimeter wavelength.

  13. Digital Filter Design with Harmonics Estimation for Power Supplies

    NASA Astrophysics Data System (ADS)

    Shah, P. J.; Saxena, R.; Chawla, M. P. S.

    2012-06-01

    The quality of voltage waveforms is nowadays an issue of the utmost importance for power utilities and electronic equipment. Modern frequency power converters generate a wide spectrum of harmonic components, which deteriorate the quality of the delivered energy, increase the energy losses as well as decrease their liability of a power supplies. In large converters systems not only harmonics, but also considerable interharmonics strongly deteriorate the quality of the power supply voltage. The estimation of the components parameters is very important for control and protection tasks. Digital low pass filter overcome the voltage drift, temperature drift and time drift problems and can be used for harmonic detection for better utilization in real-time. Real-time detection of harmonics can be implemented using MATLAB software and developing simulation circuit set up. With the appropriate cutoff frequency f c and nth order of filter, low pass filter and band-pass filter for real-time harmonic detection can be analyzed. In this paper the aim is to design filters using different methods including Prony analysis. The monitoring of power system harmonics an important issue in the frame of modern power system management and control can be achieved easily using digital filters.

  14. Boosting Power Density of Microbial Fuel Cells with 3D Nitrogen-Doped Graphene Aerogel Electrode.

    PubMed

    Yang, Yang; Liu, Tianyu; Zhu, Xun; Zhang, Feng; Ye, Dingding; Liao, Qiang; Li, Yat

    2016-08-01

    A 3D nitrogen-doped graphene aerogel (N-GA) as an anode material for microbial fuel cells (MFCs) is reported. Electron microscopy images reveal that the N-GA possesses hierarchical porous structure that allows efficient diffusion of both bacterial cells and electron mediators in the interior space of 3D electrode, and thus, the colonization of bacterial communities. Electrochemical impedance spectroscopic measurements further show that nitrogen doping considerably reduces the charge transfer resistance and internal resistance of GA, which helps to enhance the MFC power density. Importantly, the dual-chamber milliliter-scale MFC with N-GA anode yields an outstanding volumetric power density of 225 ± 12 W m(-3) normalized to the total volume of the anodic chamber (750 ± 40 W m(-3) normalized to the volume of the anode). These power densities are the highest values report for milliliter-scale MFCs with similar chamber size (25 mL) under the similar measurement conditions. The 3D N-GA electrode shows great promise for improving the power generation of MFC devices.

  15. Boosting Power Density of Microbial Fuel Cells with 3D Nitrogen‐Doped Graphene Aerogel Electrode

    PubMed Central

    Yang, Yang; Liu, Tianyu; Zhang, Feng; Ye, Dingding; Liao, Qiang

    2016-01-01

    A 3D nitrogen‐doped graphene aerogel (N‐GA) as an anode material for microbial fuel cells (MFCs) is reported. Electron microscopy images reveal that the N‐GA possesses hierarchical porous structure that allows efficient diffusion of both bacterial cells and electron mediators in the interior space of 3D electrode, and thus, the colonization of bacterial communities. Electrochemical impedance spectroscopic measurements further show that nitrogen doping considerably reduces the charge transfer resistance and internal resistance of GA, which helps to enhance the MFC power density. Importantly, the dual‐chamber milliliter‐scale MFC with N‐GA anode yields an outstanding volumetric power density of 225 ± 12 W m−3 normalized to the total volume of the anodic chamber (750 ± 40 W m−3 normalized to the volume of the anode). These power densities are the highest values report for milliliter‐scale MFCs with similar chamber size (25 mL) under the similar measurement conditions. The 3D N‐GA electrode shows great promise for improving the power generation of MFC devices. PMID:27818911

  16. Quantification of blood perfusion using 3D power Doppler: an in-vitro flow phantom study

    NASA Astrophysics Data System (ADS)

    Raine-Fenning, N. J.; Ramnarine, K. V.; Nordin, N. M.; Campbell, B. K.

    2004-01-01

    Three-dimensional (3D) power Doppler data is increasingly used to assess and quantify blood flow and tissue perfusion. The objective of this study was to assess the validity of common 3D power Doppler ‘vascularity’ indices by quantification in well characterised in-vitro flow models. A computer driven gear pump was used to circulate a steady flow of a blood mimicking fluid through various well characterised flow phantoms to investigate the effect of the number of flow channels, flow rate, depth dependent tissue attenuation, blood mimic scatter particle concentration and ultrasound settings. 3D Power Doppler data were acquired with a Voluson 530D scanner and 7.5 MHz transvaginal transducer (GE Kretz). Virtual Organ Computer-aided Analysis software (VOCAL) was used to quantify the vascularisation index (VI), flow index (FI) and vascularisation-flow index (VFI). The vascular indices were affected by many factors, some intuitive and some with more complex or unexpected relationships (e.g. VI increased linearly with an increase in flow rate, blood mimic scatter particle concentration and number of flow channels, and had a complex dependence on pulse repetition frequency). Use of standardised settings and appropriate calibration are required in any attempt at relating ‘vascularity indices’ with flow.

  17. 3D numerical thermal stress analysis of the high power target for the SLC Positron Source

    SciTech Connect

    Reuter, E.M.; Hodgson, J.A.

    1991-05-01

    The volumetrically nonuniform power deposition of the incident 33 GeV electron beam in the SLC Positron Source Target is hypothesized to be the most likely cause target failure. The resultant pulsed temperature distributions are known to generate complicated stress fields with no known closed-form analytical solution. 3D finite element analyses of these temperature distributions and associated thermal stress fields in the new High Power Target are described here. Operational guidelines based on the results of these analyses combined with assumptions made about the fatigue characteristics of the exotic target material are proposed. 6 refs., 4 figs.

  18. High power density microbial fuel cell with flexible 3D graphene-nickel foam as anode.

    PubMed

    Wang, Hanyu; Wang, Gongming; Ling, Yichuan; Qian, Fang; Song, Yang; Lu, Xihong; Chen, Shaowei; Tong, Yexiang; Li, Yat

    2013-11-07

    The structure and electrical conductivity of anode play a significant role in the power generation of microbial fuel cells (MFCs). In this study, we developed a three-dimensional (3D) reduced graphene oxide-nickel (denoted as rGO-Ni) foam as an anode for MFC through controlled deposition of rGO sheets onto the nickel foam substrate. The loading amount of rGO sheets and electrode surface area can be controlled by the number of rGO loading cycles. 3D rGO-Ni foam anode provides not only a large accessible surface area for microbial colonization and electron mediators, but also a uniform macro-porous scaffold for effective mass diffusion of the culture medium. Significantly, at a steady state of the power generation, the MFC device with flexible rGO-Ni electrodes produced an optimal volumetric power density of 661 W m(-3) calculated based on the volume of anode material, or 27 W m(-3) based on the volume of the anode chamber. These values are substantially higher than that of plain nickel foam, and other conventional carbon based electrodes (e.g., carbon cloth, carbon felt, and carbon paper) measured in the same conditions. To our knowledge, this is the highest volumetric power density reported for mL-scale MFC device with a pure strain of Shewanella oneidensis MR-1. We also demonstrated that the MFC device can be operated effectively in a batch-mode at least for a week. These new 3D rGO-Ni electrodes show great promise for improving the power generation of MFC devices.

  19. Systematic harmonic power laws inter-relating multiple fundamental constants

    NASA Astrophysics Data System (ADS)

    Chakeres, Donald; Buckhanan, Wayne; Andrianarijaona, Vola

    2017-01-01

    Power laws and harmonic systems are ubiquitous in physics. We hypothesize that 2, π, the electron, Bohr radius, Rydberg constant, neutron, fine structure constant, Higgs boson, top quark, kaons, pions, muon, Tau, W, and Z when scaled in a common single unit are all inter-related by systematic harmonic powers laws. This implies that if the power law is known it is possible to derive a fundamental constant's scale in the absence of any direct experimental data of that constant. This is true for the case of the hydrogen constants. We created a power law search engine computer program that randomly generated possible positive or negative powers searching when the product of logical groups of constants equals 1, confirming they are physically valid. For 2, π, and the hydrogen constants the search engine found Planck's constant, Coulomb's energy law, and the kinetic energy law. The product of ratios defined by two constants each was the standard general format. The search engine found systematic resonant power laws based on partial harmonic fraction powers of the neutron for all of the constants with products near 1, within their known experimental precision, when utilized with appropriate hydrogen constants. We conclude that multiple fundamental constants are inter-related within a harmonic power law system.

  20. Triboelectric Nanogenerators as a Self-Powered 3D Acceleration Sensor.

    PubMed

    Pang, Yao Kun; Li, Xiao Hui; Chen, Meng Xiao; Han, Chang Bao; Zhang, Chi; Wang, Zhong Lin

    2015-09-02

    A novel self-powered acceleration sensor based on triboelectric nanogenerator is proposed, which consists of an outer transparent shell and an inner mass-spring-damper mechanical system. The PTFE films on the mass surfaces can slide between two aluminum electrodes on an inner wall owing to the acceleration in the axis direction. On the basis of the coupling of triboelectric and electrostatic effects, the potential difference between the two aluminum electrodes is generated in proportion to the mass displacement, which can be used to characterize the acceleration in the axis direction with a detection range from about 13.0 to 40.0 m/s(2) at a sensitivity of 0.289 V·s(2)/m. With the integration of acceleration sensors in three axes, a self-powered 3D acceleration sensor is developed for vector acceleration measurement in any direction. The self-powered 3D acceleration sensor has excellent performance in the stability test, and the output voltages have a little decrease of ∼6% after 4000 cycles. Moreover, the self-powered acceleration sensor can be used to measure high collision acceleration, which has potential practicability in automobile security systems.

  1. Influence of Pulse Repetition Frequency on 3-D Power Doppler Quantification.

    PubMed

    Soares, Carlos A M; Pavan, Theo Z; Miyague, Andre H; Kudla, Marek; Martins, Wellington P

    2016-12-01

    Three-dimensional power Doppler quantification has limited application because of its high dependency on attenuation. The purpose of the study described here was to assess if different degrees of attenuation, depending on pulse repetition frequency (PRF) adjustment, alter 3-D power Doppler quantification in a region of 100% moving blood when using vascularization index, flow index and vascularization flow index (VFI). A cubic-shaped gelatin phantom with a 1.8-mm-internal-diameter silicon tube was used. The tube, placed at 45° to the phantom's surface, was filled with blood-mimicking fluid with as constant maximum velocity of 30 cm/s. Two different attenuation blocks (low and high attenuation) were alternatively placed between the phantom and the transvaginal transducer. One single observer acquired 10 data sets for each PRF level from 0.3 to 7.5 kHz, using the high- and low-attenuation blocks, for a total of 200 3-D power Doppler data sets. We assessed VFI from 1.5-mm-diameter spherical samples, virtually placed inside the tube, always at the same position. No difference was noted between high- and low-attenuation VFI values when using a PRF of 0.3 kHz. As PRF increased, it was observed that VFI quantification progressively differed between low and high attenuation. Also, a slope on VFI values for both high- and low-attenuation models could be observed when increasing PRF, particularly above 4.0 kHz. We concluded that PRF adjustment is very relevant when using VFI to quantify 3-D power Doppler signal.

  2. A zero power harmonic transponder sensor for ubiquitous wireless μL liquid-volume monitoring.

    PubMed

    Huang, Haiyu; Chen, Pai-Yen; Hung, Cheng-Hsien; Gharpurey, Ranjit; Akinwande, Deji

    2016-01-06

    Autonomous liquid-volume monitoring is crucial in ubiquitous healthcare. However, conventional approach is based on either human visual observation or expensive detectors, which are costly for future pervasive monitoring. Here we introduce a novel approach based on passive harmonic transponder antenna sensor and frequency hopping spread spectrum (FHSS) pattern analysis, to provide a very low cost wireless μL-resolution liquid-volume monitoring without battery or digital circuits. In our conceptual demonstration, the harmonic transponder comprises of a passive nonlinear frequency multiplier connected to a metamaterial-inspired 3-D antenna designed to be highly sensitive to the liquid-volume within a confined region. The transponder first receives some FHSS signal from an interrogator, then converts such signal to its harmonic band and re-radiates through the antenna sensor. The harmonic signal is picked up by a sniffer receiver and decoded through pattern analysis of the high dimensional FHSS signal strength data. A robust, zero power, absolute accuracy wireless liquid-volume monitoring is realized in the presence of strong direct coupling, background scatters, distance variance as well as near-field human-body interference. The concepts of passive harmonic transponder sensor, metamaterial-inspired antenna sensor, and FHSS pattern analysis based sensor decoding may help establishing cost-effective, energy-efficient and intelligent wireless pervasive healthcare monitoring platforms.

  3. A zero power harmonic transponder sensor for ubiquitous wireless μL liquid-volume monitoring

    NASA Astrophysics Data System (ADS)

    Huang, Haiyu; Chen, Pai-Yen; Hung, Cheng-Hsien; Gharpurey, Ranjit; Akinwande, Deji

    2016-01-01

    Autonomous liquid-volume monitoring is crucial in ubiquitous healthcare. However, conventional approach is based on either human visual observation or expensive detectors, which are costly for future pervasive monitoring. Here we introduce a novel approach based on passive harmonic transponder antenna sensor and frequency hopping spread spectrum (FHSS) pattern analysis, to provide a very low cost wireless μL-resolution liquid-volume monitoring without battery or digital circuits. In our conceptual demonstration, the harmonic transponder comprises of a passive nonlinear frequency multiplier connected to a metamaterial-inspired 3-D antenna designed to be highly sensitive to the liquid-volume within a confined region. The transponder first receives some FHSS signal from an interrogator, then converts such signal to its harmonic band and re-radiates through the antenna sensor. The harmonic signal is picked up by a sniffer receiver and decoded through pattern analysis of the high dimensional FHSS signal strength data. A robust, zero power, absolute accuracy wireless liquid-volume monitoring is realized in the presence of strong direct coupling, background scatters, distance variance as well as near-field human-body interference. The concepts of passive harmonic transponder sensor, metamaterial-inspired antenna sensor, and FHSS pattern analysis based sensor decoding may help establishing cost-effective, energy-efficient and intelligent wireless pervasive healthcare monitoring platforms.

  4. A zero power harmonic transponder sensor for ubiquitous wireless μL liquid-volume monitoring

    PubMed Central

    Huang, Haiyu; Chen, Pai-Yen; Hung, Cheng-Hsien; Gharpurey, Ranjit; Akinwande, Deji

    2016-01-01

    Autonomous liquid-volume monitoring is crucial in ubiquitous healthcare. However, conventional approach is based on either human visual observation or expensive detectors, which are costly for future pervasive monitoring. Here we introduce a novel approach based on passive harmonic transponder antenna sensor and frequency hopping spread spectrum (FHSS) pattern analysis, to provide a very low cost wireless μL-resolution liquid-volume monitoring without battery or digital circuits. In our conceptual demonstration, the harmonic transponder comprises of a passive nonlinear frequency multiplier connected to a metamaterial-inspired 3-D antenna designed to be highly sensitive to the liquid-volume within a confined region. The transponder first receives some FHSS signal from an interrogator, then converts such signal to its harmonic band and re-radiates through the antenna sensor. The harmonic signal is picked up by a sniffer receiver and decoded through pattern analysis of the high dimensional FHSS signal strength data. A robust, zero power, absolute accuracy wireless liquid-volume monitoring is realized in the presence of strong direct coupling, background scatters, distance variance as well as near-field human-body interference. The concepts of passive harmonic transponder sensor, metamaterial-inspired antenna sensor, and FHSS pattern analysis based sensor decoding may help establishing cost-effective, energy-efficient and intelligent wireless pervasive healthcare monitoring platforms. PMID:26732251

  5. Fiber optic vibration sensor for high-power electric machines realized using 3D printing technology

    NASA Astrophysics Data System (ADS)

    Igrec, Bojan; Bosiljevac, Marko; Sipus, Zvonimir; Babic, Dubravko; Rudan, Smiljko

    2016-03-01

    The objective of this work was to demonstrate a lightweight and inexpensive fiber-optic vibration sensor, built using 3D printing technology, for high-power electric machines and similar applications. The working principle is based on modulating the light intensity using a blade attached to a bendable membrane. The sensor prototype was manufactured using PolyJet Matrix technology with DM 8515 Grey 35 Polymer. The sensor shows linear response, expected bandwidth (< 150 Hz), and from our measurements we estimated the damping ratio for used polymer to be ζ ≍ 0.019. The developed prototype is simple to assemble, adjust, calibrate and repair.

  6. Development of a 3D FEL code for the simulation of a high-gain harmonic generation experiment.

    SciTech Connect

    Biedron, S. G.

    1999-02-26

    Over the last few years, there has been a growing interest in self-amplified spontaneous emission (SASE) free-electron lasers (FELs) as a means for achieving a fourth-generation light source. In order to correctly and easily simulate the many configurations that have been suggested, such as multi-segmented wigglers and the method of high-gain harmonic generation, we have developed a robust three-dimensional code. The specifics of the code, the comparison to the linear theory as well as future plans will be presented.

  7. Self-Excitation and Harmonics in Wind Power Generation

    SciTech Connect

    Muljadi, E.; Butterfield, C. P.; Romanowitz, H.; Yinger, R.

    2005-11-01

    Traditional wind turbines are commonly equipped with induction generators because they are inexpensive, rugged, and require very little maintenance. Unfortunately, induction generators require reactive power from the grid to operate; capacitor compensation is often used. Because the level of required reactive power varies with the output power, the capacitor compensation must be adjusted as the output power varies. The interactions among the wind turbine, the power network, and the capacitor compensation are important aspects of wind generation that may result in self-excitation and higher harmonic content in the output current. This paper examines the factors that control these phenomena and gives some guidelines on how they can be controlled or eliminated.

  8. A 3-D Magnetic Analysis of a Linear Alternator For a Stirling Power System

    NASA Technical Reports Server (NTRS)

    Geng, Steven M.; Schwarze, Gene E.; Niedra, Janis M.

    2000-01-01

    The NASA Glenn Research Center and the Department of Energy (DOE) are developing advanced radioisotope Stirling convertors, under contract with Stirling Technology Company (STC), for space applications. Of critical importance to the successful development of the Stirling convertor for space power applications is the development of a lightweight and highly efficient linear alternator. This paper presents a 3-D finite element method (FEM) approach for evaluating Stirling convertor linear alternators. Preliminary correlations with open-circuit voltage measurements provide an encouraging level of confidence in the model. Spatial plots of magnetic field strength (H) are presented in the region of the exciting permanent magnets. These plots identify regions of high H, where at elevated temperature and under electrical load, the potential to alter the magnetic moment of the magnets exists. This implies the need for further testing and analysis.

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

    NASA Astrophysics Data System (ADS)

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

    2016-03-01

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

  10. A hybridizable discontinuous Galerkin method combined to a Schwarz algorithm for the solution of 3d time-harmonic Maxwell's equation

    NASA Astrophysics Data System (ADS)

    Li, Liang; Lanteri, Stéphane; Perrussel, Ronan

    2014-01-01

    A Schwarz-type domain decomposition method is presented for the solution of the system of 3d time-harmonic Maxwell's equations. We introduce a hybridizable discontinuous Galerkin (HDG) scheme for the discretization of the problem based on a tetrahedrization of the computational domain. The discrete system of the HDG method on each subdomain is solved by an optimized sparse direct (LU factorization) solver. The solution of the interface system in the domain decomposition framework is accelerated by a Krylov subspace method. The formulation and the implementation of the resulting DD-HDG (Domain Decomposed-Hybridizable Discontinuous Galerkin) method are detailed. Numerical results show that the resulting DD-HDG solution strategy has an optimal convergence rate and can save both CPU time and memory cost compared to a classical upwind flux-based DD-DG (Domain Decomposed-Discontinuous Galerkin) approach.

  11. Identification and tracking of harmonic sources in a power system using a Kalman filter

    SciTech Connect

    Ma, H.; Girgis, A.A.

    1996-07-01

    In this paper, two problems have been addressed on harmonic sources identification: the optimal locations of a limited number of harmonic meters and the optimal dynamic estimates of harmonic source locations and their injections in unbalanced three-phase power systems. A Kalman filtering is used to attack these problems. System error covariance analysis by the Kalman filter associated with a harmonic injection estimate determines the optimal arrangement of limited harmonic meters. Based on the optimally-arranged harmonic metering locations, the Kalman filter then yields the optimal dynamic estimates of harmonic injections with a few noisy harmonic measurements. The method is dynamic and has the capability of identifying, analyzing and tracking each harmonic injection at all buses in unbalanced three-phase power systems. Actual recorded harmonic measurements and simulated data in a power distribution system are provided to prove the efficiency of this approach.

  12. High-speed low-power analog ASICs for a 3D neuroprocessor

    NASA Astrophysics Data System (ADS)

    Duong, Tuan A.; Kemeny, Sabrina E.; Tran, Mua D.; Daud, Taher; Thakoor, Anilkumar P.

    1995-03-01

    A particularly challenging neural network application requiring high-speed and intensive image processing capability is target acquisition and discrimination. It requires spatio-temporal recognition of point and resolved targets at high speeds. A reconfigurable neural architecture may discriminate targets from clutter or classify targets once resolved. By mating a 64 X 64 pixel array infrared (IR) image sensor to a 3-D stack (cube) of 64 neural-net ICs along respective edges, every pixel would directly input to a neural network, thereby processing the information with full parallelism. However, the `cube' has to operate at 90 degree(s)K with < 250 nanoseconds signal processing speed and approximately 2 watts of power dissipation. Analog circuitry, where the spatially parallel input to the neural networks is also analog, would make this possible. Digital neural processing would require analog-to-digital converters on each IC, impractical with the power constraint. A versatile reconfigurable circuit is presented that offers a variety of neural architectures: multilayer perceptron, cascade backpropagation, and template matching with winner-take-all (WTA) circuitry. Special designs of analog neuron and synapse implemented in VLSI are presented which bear out high speed response both at room and low temperatures with synapse-neuron signal propagation times of approximately 100 ns.

  13. Cloud 3D Effects Evidenced in Landsat Power Spectra and Autocorrelation Functions

    NASA Technical Reports Server (NTRS)

    Oreopoulos, Lazaros; Marshak, Alexander; Cahalan, Robert F.; Wen, Guoyong

    1999-01-01

    the spectral signatures of decorrelation between reflectance and optical depth at large scales becoming stronger as the magnitude of cloud top variations increase. Finally, the usefulness of power spectral analysis in evaluating the skill of novel optical depth retrieval techniques in removing 3D radiative effects is demonstrated. New techniques using inverse Non-local Independent Pixel Approximation (NIPA) and Normalized Difference of Nadir Reflectivity (NDNR) yield optical depth fields which better match the scale-by-scale variability of the true optical depth field.

  14. High gain amplifiers: Power oscillations and harmonic generation

    SciTech Connect

    Dattoli, G.; Ottaviani, P. L.; Pagnutti, S.

    2007-08-01

    We discuss the power oscillations in saturated high gain free electron laser amplifiers and show that the relevant period can be written in terms of the gain length. We use simple arguments following from the solution of the pendulum equation in terms of Jacobi elliptic functions. Nontrivial effects due to nonlinear harmonic generation and inhomogeneous broadening are discussed too, as well as the saturated dynamics of short pulses.

  15. Operation of the unified power flow controller as harmonic isolator

    SciTech Connect

    Enslin, J.H.R.; Zhao, J.; Spee, R.

    1996-11-01

    The unified power flow controller (UPFC) is a tool in the implementation of Flexible AC Transmission Systems (FACTS). It provides for the equivalent of static VAr compensation and series injection using back-to-back force commutated converters. This paper proposes a control strategy to extend UPFC operation to allow for the isolation of harmonics due to nonlinear loads. Simulation results based on the Electromagnetic Transients Program (EMTP) are used to illustrate device performance in a power system environment. Experimental results based on a single phase laboratory implementation verify the proposed control algorithm.

  16. 3D SIMULATIONS OF REALISTIC POWER HALOS IN MAGNETOHYDROSTATIC SUNSPOT ATMOSPHERES: LINKING THEORY AND OBSERVATION

    SciTech Connect

    Rijs, Carlos; Przybylski, Damien; Moradi, Hamed; Cally, Paul S.; Shelyag, Sergiy; Rajaguru, S. P.

    2016-01-20

    The well-observed acoustic halo is an enhancement in time-averaged Doppler velocity and intensity power with respect to quiet-Sun values that is prominent for the weak and highly inclined field around the penumbra of sunspots and active regions. We perform 3D linear wave modeling with realistic distributed acoustic sources in a magnetohydrostatic sunspot atmosphere and compare the resultant simulation enhancements with multiheight SDO observations of the phenomenon. We find that simulated halos are in good qualitative agreement with observations. We also provide further proof that the underlying process responsible for the halo is the refraction and return of fast magnetic waves that have undergone mode conversion at the critical a = c atmospheric layer. In addition, we also find strong evidence that fast Alfvén mode conversion plays a significant role in the structure of the halo, taking energy away from photospheric and chromospheric heights in the form of field-aligned Alfvén waves. This conversion process may explain the observed “dual-ring” halo structure at higher (>8 mHz) frequencies.

  17. Reactive power and harmonic compensation based on the generalized instantaneous reactive power theory for three-phase power systems

    SciTech Connect

    Peng, Fang Zheng; Lai, Jih-Sheng

    1996-10-01

    A generalized theory of instantaneous reactive power for three-phase power systems is proposed in this paper. This theory gives a generalized definition of instantaneous reactive power, which is valid for sinusoidal or nonsinusoidal, balanced or unbalanced, three- phase power systems with or without zero-sequence currents and/or voltages. The properties and physical meanings of the newly defined instantaneous reactive power are discussed in detail. With this new reactive power theory, it is very easy to calculate and decompose all components, such as fundamental active/reactive power and current, harmonic current, etc. Reactive power and/or harmonic compensation systems for a three-phase distorted power system with and without zero-sequence components in the source voltage and/or load current are then used as examples to demonstrate the measurement, decomposition, and compensation of reactive power and harmonics.

  18. Transvaginal 3-d power Doppler ultrasound evaluation of the fetal brain at 10-13 weeks' gestation.

    PubMed

    Hata, Toshiyuki; Tanaka, Hirokazu; Noguchi, Junko

    2012-03-01

    The objective of this study was to measure the fetal brain volume (FBV) and vascularization and blood flow using transvaginal 3-D power Doppler (3DPD) ultrasound late in the first trimester of pregnancy. 3DPD ultrasound examinations with the VOCAL imaging analysis program were performed on 36 normal fetuses from 10-13 weeks' gestation. FBV and 3DPD indices related to the fetal brain vascularization (vascularization index [VI], flow index [FI] and vascularization flow index [VFI]) were calculated in each fetus. Intra- and interclass correlation coefficients and intra- and interobserver agreements of measurements were assessed. FBV was curvilinearly correlated well with the gestational age (R2 = 0.861, p < 0.0001). All 3-D power Doppler indices (VI, FI and VFI) showed no change at 10-13 weeks' gestation. FBV and all 3-D power Doppler indices (VI, FI and VFI) showed a correlation > 0.82, with good intra- and interobserver agreement. Our findings suggest that 3-D ultrasound is a superior means of evaluating the FBV in utero, and that 3-D power Doppler ultrasound histogram analysis may provide new information on the assessment of fetal brain perfusion.

  19. Novel and powerful 3D adaptive crisp active contour method applied in the segmentation of CT lung images.

    PubMed

    Rebouças Filho, Pedro Pedrosa; Cortez, Paulo César; da Silva Barros, Antônio C; C Albuquerque, Victor Hugo; R S Tavares, João Manuel

    2017-01-01

    The World Health Organization estimates that 300 million people have asthma, 210 million people have Chronic Obstructive Pulmonary Disease (COPD), and, according to WHO, COPD will become the third major cause of death worldwide in 2030. Computational Vision systems are commonly used in pulmonology to address the task of image segmentation, which is essential for accurate medical diagnoses. Segmentation defines the regions of the lungs in CT images of the thorax that must be further analyzed by the system or by a specialist physician. This work proposes a novel and powerful technique named 3D Adaptive Crisp Active Contour Method (3D ACACM) for the segmentation of CT lung images. The method starts with a sphere within the lung to be segmented that is deformed by forces acting on it towards the lung borders. This process is performed iteratively in order to minimize an energy function associated with the 3D deformable model used. In the experimental assessment, the 3D ACACM is compared against three approaches commonly used in this field: the automatic 3D Region Growing, the level-set algorithm based on coherent propagation and the semi-automatic segmentation by an expert using the 3D OsiriX toolbox. When applied to 40 CT scans of the chest the 3D ACACM had an average F-measure of 99.22%, revealing its superiority and competency to segment lungs in CT images.

  20. 3D amino-induced electroless plating: a powerful toolset for localized metallization on polymer substrates.

    PubMed

    Garcia, Alexandre; Berthelot, Thomas; Viel, Pascal; Jégou, Pascale; Palacin, Serge

    2011-11-18

    The "3D amino-induced electroless plating" (3D-AIEP) process is an easy and cost-effective way to produce metallic patterns onto flexible polymer substrates with a micrometric resolution and based on the direct printing of the mask with a commercial printer. Its effectiveness is based on the covalent grafting onto substrates of a 3D polymer layer which presents the ability to entrap Pd species. Therefore, this activated Pd-loaded and 3D polymer layer acts both as a seed layer for electroless metal growth and as an interdigital layer for enhanced mechanical properties of the metallic patterns. Consequently, flexible and transparent poly(ethylene terephtalate) (PET) sheets were selectively metalized with nickel or copper patterns. The electrical properties of the obtained metallic patterns were also studied.

  1. Multi-pulse Converters and Passive Filtering to Improve Power Harmonics in an Integrated Power System

    DTIC Science & Technology

    2007-05-07

    Conversion Module Ship Service Power Rect. 10 applied to a propulsion motor that is directly coupled to the propeller shaft. To enhance reliability ...Harmonic Analysis A periodic waveform ( )f t is one that functionally satisfies ( ) ( )f t T f t+ = Equation 1 where t is time and T is the...period in seconds. The fundamental frequency ω in radians/second is then found from 2 T π ω = Equation 2 A harmonic is defined as a component

  2. The Impact of 3D Stacking and Technology Scaling on the Power and Area of Stereo Matching Processors

    PubMed Central

    Ok, Seung-Ho; Lee, Yong-Hwan; Shim, Jae Hoon; Lim, Sung Kyu; Moon, Byungin

    2017-01-01

    Recently, stereo matching processors have been adopted in real-time embedded systems such as intelligent robots and autonomous vehicles, which require minimal hardware resources and low power consumption. Meanwhile, thanks to the through-silicon via (TSV), three-dimensional (3D) stacking technology has emerged as a practical solution to achieving the desired requirements of a high-performance circuit. In this paper, we present the benefits of 3D stacking and process technology scaling on stereo matching processors. We implemented 2-tier 3D-stacked stereo matching processors with GlobalFoundries 130-nm and Nangate 45-nm process design kits and compare them with their two-dimensional (2D) counterparts to identify comprehensive design benefits. In addition, we examine the findings from various analyses to identify the power benefits of 3D-stacked integrated circuit (IC) and device technology advancements. From experiments, we observe that the proposed 3D-stacked ICs, compared to their 2D IC counterparts, obtain 43% area, 13% power, and 14% wire length reductions. In addition, we present a logic partitioning method suitable for a pipeline-based hardware architecture that minimizes the use of TSVs. PMID:28241437

  3. The Impact of 3D Stacking and Technology Scaling on the Power and Area of Stereo Matching Processors.

    PubMed

    Ok, Seung-Ho; Lee, Yong-Hwan; Shim, Jae Hoon; Lim, Sung Kyu; Moon, Byungin

    2017-02-22

    Recently, stereo matching processors have been adopted in real-time embedded systems such as intelligent robots and autonomous vehicles, which require minimal hardware resources and low power consumption. Meanwhile, thanks to the through-silicon via (TSV), three-dimensional (3D) stacking technology has emerged as a practical solution to achieving the desired requirements of a high-performance circuit. In this paper, we present the benefits of 3D stacking and process technology scaling on stereo matching processors. We implemented 2-tier 3D-stacked stereo matching processors with GlobalFoundries 130-nm and Nangate 45-nm process design kits and compare them with their two-dimensional (2D) counterparts to identify comprehensive design benefits. In addition, we examine the findings from various analyses to identify the power benefits of 3D-stacked integrated circuit (IC) and device technology advancements. From experiments, we observe that the proposed 3D-stacked ICs, compared to their 2D IC counterparts, obtain 43% area, 13% power, and 14% wire length reductions. In addition, we present a logic partitioning method suitable for a pipeline-based hardware architecture that minimizes the use of TSVs.

  4. Power line harmonic radiation: A systematic study using DEMETER spacecraft

    NASA Astrophysics Data System (ADS)

    Němec, F.; Santolík, O.; Parrot, M.; Berthelier, J. J.

    We present results of a systematic survey of Power line harmonic radiation (PLHR) observed by the DEMETER spacecraft. DEMETER is a French micro-satellite launched in June, 2004 with an altitude of orbit of about 700 km. It is designed specifically to study electromagnetic effects connected with seismic and man-made activity. All available high-resolution burst-mode electromagnetic data measured since the beginning of the mission till July 2006 (altogether about 1650 h of data) have been analyzed using an automatic identification procedure. This procedure was specially developed to search for emissions of PLHR type. It is running in DEMETER control center in Orléans, France. 49 PLHR events with frequency spacing of 50/100 or 60/120 Hz have been found, allowing us to perform a statistical study of properties of PLHR. It is shown that for all the events, the observed frequency spacing corresponds well to the power system frequency at anticipated source locations. Moreover, the frequency of the observed lines often (80%) corresponds to the exact harmonics of the power system base frequency. Finally, the most intense events are observed at lower frequencies and no weak events are observed under geomagnetically disturbed conditions.

  5. Advanced configuration of hybrid passive filter for reactive power and harmonic compensation.

    PubMed

    Kececioglu, O Fatih; Acikgoz, Hakan; Sekkeli, Mustafa

    2016-01-01

    Harmonics is one of the major power quality problems for power systems. The harmonics can be eliminated by power filters such as passive, active, and hybrid. In this study, a new passive filter configuration has been improved in addition to the existing passive filter configurations. Conventional hybrid passive filters are not successful to compensate rapidly changing reactive power demand. The proposed configure are capable of compensating both harmonics and reactive power at the same time. Simulation results show that performance of reactive power and harmonic compensation with advanced hybrid passive filter is better than conventional hybrid passive filters.

  6. Analysis of Even Harmonics Generation in an Isolated Electric Power System

    NASA Astrophysics Data System (ADS)

    Kanao, Norikazu; Hayashi, Yasuhiro; Matsuki, Junya

    Harmonics bred from loads are mainly odd order because the current waveform has half-wave symmetry. Since the even harmonics are negligibly small, those are not generally measured in electric power systems. However, even harmonics were measured at a 500/275/154kV substation in Hokuriku Electric Power Company after removal of a transmission line fault. The even harmonics caused malfunctions of protective digital relays because the relays used 4th harmonics at the input filter as automatic supervisory signal. This paper describes the mechanism of generation of the even harmonics by comparing measured waveforms with ATP-EMTP simulation results. As a result of analysis, it is cleared that even harmonics are generated by three causes. The first cause is a magnetizing current of transformers due to flux deviation by DC component of a fault current. The second one is due to harmonic conversion of a synchronous machine which generates even harmonics when direct current component or even harmonic current flow into the machine. The third one is that increase of harmonic impedance due to an isolated power system produces harmonic voltages. The design of the input filter of protective digital relays should consider even harmonics generation in an isolated power system.

  7. A supervisor for the successive 3D computations of magnetic, mechanical and acoustic quantities in power oil inductors and transformers

    SciTech Connect

    Reyne, G.; Magnin, H.; Berliat, G.; Clerc, C.

    1994-09-01

    A supervisor has been developed so as to allow successive 3D computations of different quantities by different softwares on the same physical problem. Noise of a given power oil transformer can be deduced from the surface vibrations of the tank. These vibrations are obtained through a mechanic computation whose Inputs are the electromagnetic forces provided . by an electromagnetic computation. Magnetic, mechanic and acoustic experimental data are compared with the results of the 3D computations. Stress Is put on the main characteristics of the supervisor such as the transfer of a given quantity from one mesh to the other.

  8. Compensation for Harmonic Currents and Reactive Power in Wind Power Generation System using PWM Inverter

    NASA Astrophysics Data System (ADS)

    Shinohara, Katsuji; Shinhatsubo, Kurato; Iimori, Kenichi; Yamamoto, Kichiro; Saruban, Takamichi; Yamaemori, Takahiro

    In recent year, consciousness of environmental problems is enhancing, and the price of the electric power purchased by an electric power company is established expensive for the power plant utilizing the natural energy. So, the introduction of the wind power generation is promoted in Japan. Generally, squirrel-cage induction machines are widely used as a generator in wind power generation system because of its small size, lightweight and low-cost. However, the induction machines do not have a source of excitation. Thus, it causes the inrush currents and the instantaneous voltage drop when the generator is directly connected to a power grid. To reduce the inrush currents, an AC power regulator is used. Wind power generations are frequently connected to and disconnected from the power grid. However, when the inrush currents are reduced, harmonic currents are caused by phase control of the AC power regulator. And the phase control of AC power regulator cannot control the power factor. Therefore, we propose the use of the AC power regulator to compensate for the harmonic currents and reactive power in the wind power generation system, and demonstrate the validity of its system by simulated and experimental results.

  9. CFD Code Calibration and Inlet-Fairing Effects On a 3D Hypersonic Powered-Simulation Model

    NASA Technical Reports Server (NTRS)

    Huebner, Lawrence D.; Tatum, Kenneth E.

    1993-01-01

    A three-dimensional (3D) computational study has been performed addressing issues related to the wind tunnel testing of a hypersonic powered-simulation model. The study consisted of three objectives. The first objective was to calibrate a state-of-the-art computational fluid dynamics (CFD) code in its ability to predict hypersonic powered-simulation flows by comparing CFD solutions with experimental surface pressure data. Aftbody lower surface pressures were well predicted, but lower surface wing pressures were less accurately predicted. The second objective was to determine the 3D effects on the aftbody created by fairing over the inlet; this was accomplished by comparing the CFD solutions of two closed-inlet powered configurations with a flowing- inlet powered configuration. Although results at four freestream Mach numbers indicate that the exhaust plume tends to isolate the aftbody surface from most forebody flow- field differences, a smooth inlet fairing provides the least aftbody force and moment variation compared to a flowing inlet. The final objective was to predict and understand the 3D characteristics of exhaust plume development at selected points on a representative flight path. Results showed a dramatic effect of plume expansion onto the wings as the freestream Mach number and corresponding nozzle pressure ratio are increased.

  10. Thermal optimization of second harmonic generation at high pump powers.

    PubMed

    Sahm, Alexander; Uebernickel, Mirko; Paschke, Katrin; Erbert, Götz; Tränkle, Günther

    2011-11-07

    We measure the temperature distribution of a 3 cm long periodically poled LiNbO₃ crystal in a single-pass second harmonic generation (SHG) setup at 488 nm. By means of three resistance heaters and directly mounted Pt100 sensors the crystal is subdivided in three sections. 9.4 W infrared pump light and 1.3 W of SHG light cause a de-homogenized temperature distribution of 0.2 K between the middle and back section. A sectional offset heating is used to homogenize the temperature in those two sections and thus increasing the conversion efficiency. A 15% higher SHG output power matching the prediction of our theoretical model is achieved.

  11. High harmonic generation in ZnO with a high-power mid-IR OPA

    NASA Astrophysics Data System (ADS)

    Gholam-Mirzaei, Shima; Beetar, John; Chini, Michael

    2017-02-01

    We generate high-order harmonics in a-cut (11-20) ZnO at a high repetition rate of 50 kHz, using the tunable mid-infrared pulses (3-4 μm wavelength) from a high-power optical parametric amplifier. For driving laser pulses with 3.8 μm central wavelength, we observe nonperturbative harmonic spectra that well exceed the material band gap. The harmonic spectra depend strongly on the orientation of the crystal with respect to the laser polarization, with odd harmonics exhibiting periodicities of π/2 for a polarization within the (11-20) crystal plane. Energy conversion efficiencies of ˜10-6 per harmonic are measured for the 9th-13th harmonics, yielding an average power of more than 0.2 μW for the 13th harmonic.

  12. Low-Amplitude Craniofacial EMG Power Spectral Density and 3D Muscle Reconstruction from MRI

    PubMed Central

    Wiedemann, Lukas; Chaberova, Jana; Edmunds, Kyle; Einarsdóttir, Guðrún; Ramon, Ceon

    2015-01-01

    Improving EEG signal interpretation, specificity, and sensitivity is a primary focus of many current investigations, and the successful application of EEG signal processing methods requires a detailed knowledge of both the topography and frequency spectra of low-amplitude, high-frequency craniofacial EMG. This information remains limited in clinical research, and as such, there is no known reliable technique for the removal of these artifacts from EEG data. The results presented herein outline a preliminary investigation of craniofacial EMG high-frequency spectra and 3D MRI segmentation that offers insight into the development of an anatomically-realistic model for characterizing these effects. The data presented highlights the potential for confounding signal contribution from around 60 to 200 Hz, when observed in frequency space, from both low and high-amplitude EMG signals. This range directly overlaps that of both low γ (30-50 Hz) and high γ (50-80 Hz) waves, as defined traditionally in standatrd EEG measurements, and mainly with waves presented in dense-array EEG recordings. Likewise, average EMG amplitude comparisons from each condition highlights the similarities in signal contribution of low-activity muscular movements and resting, control conditions. In addition to the FFT analysis performed, 3D segmentation and reconstruction of the craniofacial muscles whose EMG signals were measured was successful. This recapitulation of the relevant EMG morphology is a crucial first step in developing an anatomical model for the isolation and removal of confounding low-amplitude craniofacial EMG signals from EEG data. Such a model may be eventually applied in a clinical setting to ultimately help to extend the use of EEG in various clinical roles. PMID:26913150

  13. 3D reconstruction and particle acceleration properties of Coronal Shock Waves During Powerful Solar Particle Events

    NASA Astrophysics Data System (ADS)

    Plotnikov, Illya; Vourlidas, Angelos; Tylka, Allan J.; Pinto, Rui; Rouillard, Alexis; Tirole, Margot

    2016-07-01

    Identifying the physical mechanisms that produce the most energetic particles is a long-standing observational and theoretical challenge in astrophysics. Strong pressure waves have been proposed as efficient accelerators both in the solar and astrophysical contexts via various mechanisms such as diffusive-shock/shock-drift acceleration and betatron effects. In diffusive-shock acceleration, the efficacy of the process relies on shock waves being super-critical or moving several times faster than the characteristic speed of the medium they propagate through (a high Alfven Mach number) and on the orientation of the magnetic field upstream of the shock front. High-cadence, multipoint imaging using the NASA STEREO, SOHO and SDO spacecrafts now permits the 3-D reconstruction of pressure waves formed during the eruption of coronal mass ejections. Using these unprecedented capabilities, some recent studies have provided new insights on the timing and longitudinal extent of solar energetic particles, including the first derivations of the time-dependent 3-dimensional distribution of the expansion speed and Mach numbers of coronal shock waves. We will review these recent developments by focusing on particle events that occurred between 2011 and 2015. These new techniques also provide the opportunity to investigate the enigmatic long-duration gamma ray events.

  14. Vegetation Height Estimation Near Power transmission poles Via satellite Stereo Images using 3D Depth Estimation Algorithms

    NASA Astrophysics Data System (ADS)

    Qayyum, A.; Malik, A. S.; Saad, M. N. M.; Iqbal, M.; Abdullah, F.; Rahseed, W.; Abdullah, T. A. R. B. T.; Ramli, A. Q.

    2015-04-01

    Monitoring vegetation encroachment under overhead high voltage power line is a challenging problem for electricity distribution companies. Absence of proper monitoring could result in damage to the power lines and consequently cause blackout. This will affect electric power supply to industries, businesses, and daily life. Therefore, to avoid the blackouts, it is mandatory to monitor the vegetation/trees near power transmission lines. Unfortunately, the existing approaches are more time consuming and expensive. In this paper, we have proposed a novel approach to monitor the vegetation/trees near or under the power transmission poles using satellite stereo images, which were acquired using Pleiades satellites. The 3D depth of vegetation has been measured near power transmission lines using stereo algorithms. The area of interest scanned by Pleiades satellite sensors is 100 square kilometer. Our dataset covers power transmission poles in a state called Sabah in East Malaysia, encompassing a total of 52 poles in the area of 100 km. We have compared the results of Pleiades satellite stereo images using dynamic programming and Graph-Cut algorithms, consequently comparing satellites' imaging sensors and Depth-estimation Algorithms. Our results show that Graph-Cut Algorithm performs better than dynamic programming (DP) in terms of accuracy and speed.

  15. New hybrid active power filter for harmonic current suppression and reactive power compensation

    NASA Astrophysics Data System (ADS)

    Biricik, Samet; Cemal Ozerdem, Ozgur; Redif, Soydan; Sezai Dincer, Mustafa

    2016-08-01

    In the case of undistorted and balanced grid voltages, low ratio shunt active power filters (APFs) can give unity power factors and achieve current harmonic cancellation. However, this is not possible when source voltages are distorted and unbalanced. In this study, the cost-effective hybrid active power filter (HAPF) topology for satisfying the requirements of harmonic current suppression and non-active power compensation for industry is presented. An effective strategy is developed to observe the effect of the placement of power capacitors and LC filters with the shunt APF. A new method for alleviating the negative effects of a nonideal grid voltage is proposed that uses a self-tuning filter algorithm with instantaneous reactive power theory. The real-time control of the studied system was achieved with a field-programmable gate array (FPGA) architecture, which was developed using the OPAL-RT system. The performance result of the proposed HAPF system is tested and presented under nonideal supply voltage conditions.

  16. A Novel Multimode Waveguide Coupler for Accurate Power Measurement of Traveling Wave Tube Harmonic Frequencies

    NASA Technical Reports Server (NTRS)

    Wintucky, Edwin G.; Simons, Rainee N.

    2014-01-01

    This paper presents the design, fabrication and test results for a novel waveguide multimode directional coupler (MDC). The coupler fabricated from two dissimilar waveguides is capable of isolating the power at the second harmonic frequency from the fundamental power at the output port of a traveling-wave tube (TWT). In addition to accurate power measurements at harmonic frequencies, a potential application of the MDC is in the design of a beacon source for atmospheric propagation studies at millimeter-wave frequencies.

  17. Low-power continuous-wave generation of visible harmonics in silicon photonic crystal nanocavities.

    PubMed

    Galli, Matteo; Gerace, Dario; Welna, Karl; Krauss, Thomas F; O'Faolain, Liam; Guizzetti, Giorgio; Andreani, Lucio Claudio

    2010-12-06

    We present the first demonstration of frequency conversion by simultaneous second- and third-harmonic generation in a silicon photonic crystal nanocavity using continuous-wave optical excitation. We observe a bright dual wavelength emission in the blue/green (450-525 nm) and red (675-790 nm) visible windows with pump powers as low as few microwatts in the telecom bands, with conversion efficiencies of ∼ 10 (-5) /W and ∼ 10/ W(2) for the second- and third-harmonic, respectively. Scaling behaviors as a function of pump power and cavity quality-factor are demonstrated for both second- and third order processes. Successful comparison of measured and calculated emission patterns indicates that third-harmonic is a bulk effect while second-harmonic is a surface-related effect at the sidewall holes boundaries. Our results are promising for obtaining practical low-power, continuous-wave and widely tunable multiple harmonic generation on a silicon chip.

  18. A Portable Low-Power Harmonic Radar System and Conformal Tag for Insect Tracking

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Harmonic radar systems provide an effective modality for tracking insect behavior. This paper presents a harmonic radar system proposed to track the migration of the Emerald Ash Borer (EAB). The system offers a unique combination of portability, low power and small tag design. It is comprised of a...

  19. A harmonic cancellation technique for an ultrasound transducer excited by a switched-mode power converter.

    PubMed

    Tang, Sai Chun; Clement, Gregory T

    2008-02-01

    The aim of this study is to evaluate the feasibility of using harmonic cancellation for a therapeutic ultrasound transducer excited by a switched-mode power converter without an additional output filter. A switching waveform without the third harmonic was created by cascading two switched-mode power inverter modules at which their output waveforms were pi/3 phase shifted from each other. A PSPICE simulation model for the power converter output stage was developed. The simulated results were in good agreement with the measurement. The waveform and harmonic contents of the acoustic pressure generated by a 1-MHz, self-focused piezoelectric transducer with and without harmonic cancellation have been evaluated. Measured results indicated that the acoustic third harmonicto- fundamental ratio at the focus was small (-48 dB) with harmonic cancellation, compared to that without harmonic cancellation (-20 dB). The measured acoustic levels of the fifth harmonic for both cases with and without harmonic cancellation also were small (-46 dB) compared to the fundamental. This study shows that it is viable to drive a piezoelectric ultrasound transducer using a switched-mode power converter without the requirement of an additional output filter in many high-intensity focused ultrasound (HIFU) applications.

  20. Protecting ITER walls: fast ion power loads in 3D magnetic field

    NASA Astrophysics Data System (ADS)

    Kurki-Suonio, T.; Särkimäki, K.; Äkäslompolo, S.; Varje, J.; Liu, Y.; Sipilä, S.; Asunta, O.; Hirvijoki, E.; Snicker, A.; Terävä, J.; Cavinato, M.; Gagliardi, M.; Parail, V.; Saibene, G.

    2017-01-01

    The fusion alpha and beam ion with steady-state power loads in all four main operating scenarios of ITER have been evaluated by the ASCOT code. For this purpose, high-fidelity magnetic backgrounds were reconstructed, taking into account even the internal structure of the ferritic inserts and tritium breeding modules (TBM). The beam ions were found to be almost perfectly confined in all scenarios, and only the so-called hybrid scenario featured alpha loads reaching 0.5 MW due to its more triangular plasma. The TBMs were not found to jeopardize the alpha confinement, nor cause any hot spots. Including plasma response did not bring dramatic changes to the load. The ELM control coils (ECC) were simulated in the baseline scenario and found to seriously deteriorate even the beam confinement. However, the edge perturbation in this case is so large that the sources have to be re-evaluated with plasma profiles that take into account the ECC perturbation.

  1. Making Faranoff-Riley I radio sources. I. Numerical hydrodynamic 3D simulations of low-power jets

    NASA Astrophysics Data System (ADS)

    Massaglia, S.; Bodo, G.; Rossi, P.; Capetti, S.; Mignone, A.

    2016-11-01

    Context. Extragalactic radio sources have been classified into two classes, Fanaroff-Riley I and II, which differ in morphology and radio power. Strongly emitting sources belong to the edge-brightened FR II class, and weakly emitting sources to the edge-darkened FR I class. The origin of this dichotomy is not yet fully understood. Numerical simulations are successful in generating FR II morphologies, but they fail to reproduce the diffuse structure of FR Is. Aims: By means of hydro-dynamical 3D simulations of supersonic jets, we investigate how the displayed morphologies depend on the jet parameters. Bow shocks and Mach disks at the jet head, which are probably responsible for the hot spots in the FR II sources, disappear for a jet kinetic power ℒkin ≲ 1043 erg s-1. This threshold compares favorably with the luminosity at which the FR I/FR II transition is observed. Methods: The problem is addressed by numerical means carrying out 3D HD simulations of supersonic jets that propagate in a non-homogeneous medium with the ambient temperature that increases with distance from the jet origin, which maintains constant pressure. Results: The jet energy in the lower power sources, instead of being deposited at the terminal shock, is gradually dissipated by the turbulence. The jets spread out while propagating, and they smoothly decelerate while mixing with the ambient medium and produce the plumes characteristic of FR I objects. Conclusions: Three-dimensionality is an essential ingredient to explore the FR I evolution becausethe properties of turbulence in two and three dimensions are very different, since there is no energy cascade to small scales in two dimensions, and two-dimensional simulations with the same parameters lead to FRII-like behavior.

  2. A 3D paper-based enzymatic fuel cell for self-powered, low-cost glucose monitoring.

    PubMed

    Fischer, Christopher; Fraiwan, Arwa; Choi, Seokheun

    2016-05-15

    In this work, we demonstrate a novel low-cost, self-powered paper-based biosensor for glucose monitoring. The device operating mechanism is based on a glucose/oxygen enzymatic fuel cell using an electrochemical energy conversion as a transducing element for glucose monitoring. The self-powered glucose biosensor features (i) a 3D origami paper-based structure for easy system integration onto paper, (ii) an air-cathode on paper for low-cost production and easy operation, and (iii) a screen printed chitosan/glucose oxidase anode for stable current generation as an analytical signal for glucose monitoring. The sensor showed a linear range of output current at 1-5mM glucose (R(2)=0.996) with a sensitivity of 0.02 µA mM(-1). The advantages offered by such a device, including a low cost, lack of external power sources/sophisticated external transducers, and the capacity to rapidly generate reliable results, are well suited for the clinical and social settings of the developing world.

  3. Design and 3D simulation of a two-cavity wide-gap relativistic klystron amplifier with high power injection

    SciTech Connect

    Bai Xianchen; Yang Jianhua; Zhang Jiande

    2012-08-15

    By using an electromagnetic particle-in-cell (PIC) code, an S-band two-cavity wide-gap klystron amplifier (WKA) loaded with washers/rods structure is designed and investigated for high power injection application. Influences of the washers/rods structure on the high frequency characteristics and the basic operation of the amplifier are presented. Generally, the rod structure has great impacts on the space-charge potential depression and the resonant frequency of the cavities. Nevertheless, if only the resonant frequency is tuned to the desired operation frequency, effects of the rod size on the basic operation of the amplifier are expected to be very weak. The 3-dimension (3-D) PIC simulation results show an output power of 0.98 GW corresponding to an efficiency of 33% for the WKA, with a 594 keV, 5 kA electron beam guided by an external magnetic field of 1.5 Tesla. Moreover, if a conductive plane is placed near the output gap, such as the electron collector, the beam potential energy can be further released, and the RF power can be increased to about 1.07 GW with the conversion efficiency of about 36%.

  4. Third-Harmonic Envelope Feedback Method for High-Efficiency Linear Power Amplifiers

    NASA Astrophysics Data System (ADS)

    Oshima, Shoichi; Ugajin, Mamoru; Harada, Mitsuru

    A new low-power feedback structure for a power amplifier (PA) reduces signal distortion while keeping the power efficiency of the PA high. The feedback structure injects the envelope of the third-order harmonics into the input signal. In adopting this method for a class-A amplifier, we obtain over 10% higher efficiency while maintaining the same adjacent channel power ratio (ACPR). The power consumption of additional circuit is 200µW.

  5. Extremal harmonic active control of power for a monocylinder hybrid powertrain

    NASA Astrophysics Data System (ADS)

    Gauthier, Jean-Philippe; Micheau, Philippe; Cauet, Sébastien; Coirault, Patrick; Martin, Pascal

    2011-11-01

    This article presents a real-life application for the extremal harmonic active control of power [1] applied on a hybrid engine setup. The active control was adapted for a hybrid powertrain constituted of a one-cylinder diesel engine coupled with a permanent magnet synchronous machine. The problem was formulated in the harmonic domain and the control objective was to extremalize energetic criterions. Three criterions were considered: minimizing the speed ripple of the engine, maximizing the mechanical reactive power (mechanical impedance adaptation) and maximizing the active electric power for energy harvesting. The results show that, for the first and second orders of the ripple, speed oscillations can be completely cancelled and reactive power and active power can be optimized on-line. The implicit extremal controller converged rapidly, remaining stable even when the mean engine speed changed abruptly. These results confirm the robustness and the applicability of the extremal harmonic active control for industrial applications.

  6. Product development: using a 3D computer model to optimize the stability of the Rocket powered wheelchair.

    PubMed

    Pinkney, S; Fernie, G

    2001-01-01

    A three-dimensional (3D) lumped-parameter model of a powered wheelchair was created to aid the development of the Rocket prototype wheelchair and to help explore the effect of innovative design features on its stability. The model was developed using simulation software, specifically Working Model 3D. The accuracy of the model was determined by comparing both its static stability angles and dynamic behavior as it passed down a 4.8-cm (1.9") road curb at a heading of 45 degrees with the performance of the actual wheelchair. The model's predictions of the static stability angles in the forward, rearward, and lateral directions were within 9.3, 7.1, and 3.8% of the measured values, respectively. The average absolute error in the predicted position of the wheelchair as it moved down the curb was 2.2 cm/m (0.9" per 3'3") traveled. The accuracy was limited by the inability to model soft bodies, the inherent difficulties in modeling a statically indeterminate system, and the computing time. Nevertheless, it was found to be useful in investigating the effect of eight design alterations on the lateral stability of the wheelchair. Stability was quantified by determining the static lateral stability angles and the maximum height of a road curb over which the wheelchair could successfully drive on a diagonal heading. The model predicted that the stability was more dependent on the configuration of the suspension system than on the dimensions and weight distribution of the wheelchair. Furthermore, for the situations and design alterations studied, predicted improvements in static stability were not correlated with improvements in dynamic stability.

  7. RF design and processing of a power coupler for third harmonic superconducting cavities

    SciTech Connect

    Li, Jianjian; Harms, Elvin; Kubicki, Tom; Nicklaus, Dennis; Olis, Daniel; Prieto, Peter; Reid, John; Solyak, Nikolay; Wong, Thomas; /IIT, Chicago

    2007-06-01

    The FLASH user facility providing free electron laser radiation is built based on the TTF project at DESY. Fermilab has the responsibility for the design and processing of a third harmonic, 3.9 GHz, superconducting cavity which is powered via a coaxial power coupler. Six power couplers have been manufactured at CPI after successful design of the power coupler including RF simulation, multipacting calculation, and thermal analysis. The power couplers are being tested and processed with high pulsed power in an elaborate test stand at Fermilab now. This paper presents the RF design and processing work of the power coupler.

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

    PubMed

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

    2016-05-01

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

  9. High average power coherent vuv generation at 10 MHz repetition frequency by intracavity high harmonic generation.

    PubMed

    Ozawa, Akira; Zhao, Zhigang; Kuwata-Gonokami, Makoto; Kobayashi, Yohei

    2015-06-15

    Intracavity high harmonic generation was utilized to generate high average-power coherent radiation at vacuum ultraviolet (vuv) wavelengths. A ytterbium-doped fiber-laser based master-oscillator power-amplifier (MOPA) system with a 10 MHz repetition frequency was developed and used as a driving laser for an external cavity. A series of odd-order harmonic radiations was generated extending down to ∼ 30 nm (41 eV in photon energy). The 7th harmonic radiation generated was centered at 149 nm and had an average output power of up to 0.5 mW. In this way, we developed a sub-mW coherent vuv-laser with a 10 MHz repetition frequency, which, if used as an excitation laser source for photo-electron spectroscopy, could improve the signal count-rate without deterioration of the spectral-resolution caused by space-charge effects.

  10. Performance assessment of HIFU lesion detection by Harmonic Motion Imaging for Focused Ultrasound (HMIFU): A 3D finite-element-based framework with experimental validation

    PubMed Central

    Hou, Gary Y.; Luo, Jianwen; Marquet, Fabrice; Maleke, Caroline; Vappou, Jonathan; Konofagou, Elisa E.

    2014-01-01

    Harmonic Motion Imaging for Focused Ultrasound (HMIFU) is a novel high-intensity focused ultrasound (HIFU) therapy monitoring method with feasibilities demonstrated in vitro, ex vivo and in vivo. Its principle is based on Amplitude-modulated (AM) - Harmonic Motion Imaging (HMI), an oscillatory radiation force used for imaging the tissue mechanical response during thermal ablation. In this study, a theoretical framework of HMIFU is presented, comprising a customized nonlinear wave propagation model, a finite-element (FE) analysis module, and an image-formation model. The objective of this study is to develop such a framework in order to 1) assess the fundamental performance of HMIFU in detecting HIFU lesions based on the change in tissue apparent elasticity, i.e., the increasing Young's modulus, and the HIFU lesion size with respect to the HIFU exposure time and 2) validate the simulation findings ex vivo. The same HMI and HMIFU parameters as in the experimental studies were used, i.e., 4.5-MHz HIFU frequency and 25 Hz AM frequency. For a lesion-to-background Young's modulus ratio of 3, 6, and 9, the FE and estimated HMI displacement ratios were equal to 1.83, 3.69, 5.39 and 1.65, 3.19, 4.59, respectively. In experiments, the HMI displacement followed a similar increasing trend of 1.19, 1.28, and 1.78 at 10-s, 20-s, and 30-s HIFU exposure, respectively. In addition, moderate agreement in lesion size growth was also found in both simulations (16.2, 73.1 and 334.7 mm2) and experiments (26.2, 94.2 and 206.2 mm2). Therefore, the feasibility of HMIFU for HIFU lesion detection based on the underlying tissue elasticity changes was verified through the developed theoretical framework, i.e., validation of the fundamental performance of the HMIFU system for lesion detection, localization and quantification, was demonstrated both theoretically and ex vivo. PMID:22036637

  11. Performance assessment of HIFU lesion detection by harmonic motion imaging for focused ultrasound (HMIFU): a 3-D finite-element-based framework with experimental validation.

    PubMed

    Hou, Gary Y; Luo, Jianwen; Marquet, Fabrice; Maleke, Caroline; Vappou, Jonathan; Konofagou, Elisa E

    2011-12-01

    Harmonic motion imaging for focused ultrasound (HMIFU) is a novel high-intensity focused ultrasound (HIFU) therapy monitoring method with feasibilities demonstrated in vitro, ex vivo and in vivo. Its principle is based on amplitude-modulated (AM) - harmonic motion imaging (HMI), an oscillatory radiation force used for imaging the tissue mechanical response during thermal ablation. In this study, a theoretical framework of HMIFU is presented, comprising a customized nonlinear wave propagation model, a finite-element (FE) analysis module and an image-formation model. The objective of this study is to develop such a framework to (1) assess the fundamental performance of HMIFU in detecting HIFU lesions based on the change in tissue apparent elasticity, i.e., the increasing Young's modulus, and the HIFU lesion size with respect to the HIFU exposure time and (2) validate the simulation findings ex vivo. The same HMI and HMIFU parameters as in the experimental studies were used, i.e., 4.5-MHz HIFU frequency and 25 Hz AM frequency. For a lesion-to-background Young's modulus ratio of 3, 6 and 9, the FE and estimated HMI displacement ratios were equal to 1.83, 3.69 and 5.39 and 1.65, 3.19 and 4.59, respectively. In experiments, the HMI displacement followed a similar increasing trend of 1.19, 1.28 and 1.78 at 10-s, 20-s and 30-s HIFU exposure, respectively. In addition, moderate agreement in lesion size growth was found in both simulations (16.2, 73.1 and 334.7 mm(2)) and experiments (26.2, 94.2 and 206.2 mm(2)). Therefore, the feasibility of HMIFU for HIFU lesion detection based on the underlying tissue elasticity changes was verified through the developed theoretical framework, i.e., validation of the fundamental performance of the HMIFU system for lesion detection, localization and quantification, was demonstrated both theoretically and ex vivo.

  12. Self Excitation and Harmonics in Wind Power Generation: Preprint

    SciTech Connect

    Muljadi, E.; Butterfield, C. P.; Romanowitz, H.; Yinger, R.

    2004-11-01

    Traditional wind turbines are equipped with induction generators. Induction generators are preferred because they are inexpensive, rugged, and require very little maintenance. Unfortunately, induction generators require reactive power from the grid to operate. Because reactive power varies with the output power, the terminal voltage at the generator may become too low to compensate the induction generator. The interactions among the wind turbine, the power network, and the capacitor compensation, are important aspects of wind generation. In this paper, we will show the interactions among the induction generator, capacitor compensation, power system network, and magnetic saturations and examine the cause of resonance conditions and self-excitation.

  13. Power Doppler myocardial contrast echocardiography using an improved multiple frame triggered Harmonic Angio technique.

    PubMed

    Murthy, T H; Locricchio, E; Kuersten, B; Li, P; Baisch, C; Vannan, M A

    2001-04-01

    Although B-mode harmonic, intermittent-triggered myocardial contrast echocardiography (MCE) is a well-established technique, a variety of MCE techniques have been introduced recently to improve myocardial opacification. One such technique uses a power Doppler method in conjunction with multiple frame triggering (MFT), but has been limited by nonuniform microbubble destruction and blooming as well as motion artifacts. Utilizing two different contrast agents, Definity and Optison, we tested the feasibility of an improved version of Harmonic Angio MFT that utilizes a lower transmit frequency, reduced packet size, and more stringent wall filter in normal volunteers and in patients with known perfusion defects. The results showed that Harmonic Angio MFT produced fill frames with readily visible opacification and destruction frames with little visible opacification. The patterns of opacification also correlated with the expected perfusion patterns in both groups of subjects. Thus, Harmonic Angio MFT appears to be a promising new MCE technique.

  14. Photovoltaic power converter system with a controller configured to actively compensate load harmonics

    DOEpatents

    de Rooij, Michael Andrew; Steigerwald, Robert Louis; Delgado, Eladio Clemente

    2008-12-16

    Photovoltaic power converter system including a controller configured to reduce load harmonics is provided. The system comprises a photovoltaic array and an inverter electrically coupled to the array to generate an output current for energizing a load connected to the inverter and to a mains grid supply voltage. The system further comprises a controller including a first circuit coupled to receive a load current to measure a harmonic current in the load current. The controller includes a second circuit to generate a fundamental reference drawn by the load. The controller further includes a third circuit for combining the measured harmonic current and the fundamental reference to generate a command output signal for generating the output current for energizing the load connected to the inverter. The photovoltaic system may be configured to compensate harmonic currents that may be drawn by the load.

  15. Higher-order power harmonics of pulsed electrical stimulation modulates corticospinal contribution of peripheral nerve stimulation.

    PubMed

    Chen, Chiun-Fan; Bikson, Marom; Chou, Li-Wei; Shan, Chunlei; Khadka, Niranjan; Chen, Wen-Shiang; Fregni, Felipe

    2017-03-03

    It is well established that electrical-stimulation frequency is crucial to determining the scale of induced neuromodulation, particularly when attempting to modulate corticospinal excitability. However, the modulatory effects of stimulation frequency are not only determined by its absolute value but also by other parameters such as power at harmonics. The stimulus pulse shape further influences parameters such as excitation threshold and fiber selectivity. The explicit role of the power in these harmonics in determining the outcome of stimulation has not previously been analyzed. In this study, we adopted an animal model of peripheral electrical stimulation that includes an amplitude-adapted pulse train which induces force enhancements with a corticospinal contribution. We report that the electrical-stimulation-induced force enhancements were correlated with the amplitude of stimulation power harmonics during the amplitude-adapted pulse train. In an exploratory analysis, different levels of correlation were observed between force enhancement and power harmonics of 20-80 Hz (r = 0.4247, p = 0.0243), 100-180 Hz (r = 0.5894, p = 0.0001), 200-280 Hz (r = 0.7002, p < 0.0001), 300-380 Hz (r = 0.7449, p < 0.0001), 400-480 Hz (r = 0.7906, p < 0.0001), 500-600 Hz (r = 0.7717, p < 0.0001), indicating a trend of increasing correlation, specifically at higher order frequency power harmonics. This is a pilot, but important first demonstration that power at high order harmonics in the frequency spectrum of electrical stimulation pulses may contribute to neuromodulation, thus warrant explicit attention in therapy design and analysis.

  16. Higher-order power harmonics of pulsed electrical stimulation modulates corticospinal contribution of peripheral nerve stimulation

    PubMed Central

    Chen, Chiun-Fan; Bikson, Marom; Chou, Li-Wei; Shan, Chunlei; Khadka, Niranjan; Chen, Wen-Shiang; Fregni, Felipe

    2017-01-01

    It is well established that electrical-stimulation frequency is crucial to determining the scale of induced neuromodulation, particularly when attempting to modulate corticospinal excitability. However, the modulatory effects of stimulation frequency are not only determined by its absolute value but also by other parameters such as power at harmonics. The stimulus pulse shape further influences parameters such as excitation threshold and fiber selectivity. The explicit role of the power in these harmonics in determining the outcome of stimulation has not previously been analyzed. In this study, we adopted an animal model of peripheral electrical stimulation that includes an amplitude-adapted pulse train which induces force enhancements with a corticospinal contribution. We report that the electrical-stimulation-induced force enhancements were correlated with the amplitude of stimulation power harmonics during the amplitude-adapted pulse train. In an exploratory analysis, different levels of correlation were observed between force enhancement and power harmonics of 20–80 Hz (r = 0.4247, p = 0.0243), 100–180 Hz (r = 0.5894, p = 0.0001), 200–280 Hz (r = 0.7002, p < 0.0001), 300–380 Hz (r = 0.7449, p < 0.0001), 400–480 Hz (r = 0.7906, p < 0.0001), 500–600 Hz (r = 0.7717, p < 0.0001), indicating a trend of increasing correlation, specifically at higher order frequency power harmonics. This is a pilot, but important first demonstration that power at high order harmonics in the frequency spectrum of electrical stimulation pulses may contribute to neuromodulation, thus warrant explicit attention in therapy design and analysis. PMID:28256638

  17. Strong magnetoelastic coupling at the transition from harmonic to anharmonic order in NaFe(WO 4)2 with 3 d5 configuration

    NASA Astrophysics Data System (ADS)

    Holbein, S.; Ackermann, M.; Chapon, L.; Steffens, P.; Gukasov, A.; Sazonov, A.; Breunig, O.; Sanders, Y.; Becker, P.; Bohatý, L.; Lorenz, T.; Braden, M.

    2016-09-01

    The crystal structure of the double tungstate NaFe (WO4)2 arises from that of the spin-driven multiferroic MnWO4 by inserting nonmagnetic Na layers. NaFe (WO4)2 exhibits a three-dimensional incommensurate spin-spiral structure at low temperature and zero magnetic field, which, however, competes with commensurate order induced by magnetic field. The incommensurate zero-field phase corresponds to the condensation of a single irreducible representation but it does not imply ferroelectric polarization because spirals with opposite chirality coexist. Sizable anharmonic modulations emerge in this incommensurate structure, which are accompanied by large magnetoelastic anomalies, while the onset of the harmonic order is invisible in the thermal-expansion coefficient. In magnetic fields applied along the monoclinic axis, we observe a first-order transition to a commensurate structure that again is accompanied by large magnetoelastic effects. The large magnetoelastic coupling, a reduction of the b lattice parameter, is thus associated only with the commensurate order. Upon releasing the field at low temperature, the magnetic order transforms to another commensurate structure that considerably differs from the incommensurate low-temperature phase emerging upon zero-field cooling. The latter phase, which exhibits a reduced ordered moment, seems to be metastable.

  18. The harmonic impact of electric vehicle battery chargers on residential power distribution

    SciTech Connect

    Wang, Y.; O`Connell, R.M.; Brownfield, G.

    1999-11-01

    Electric vehicles (EV), which are powered by battery-driven electric motors, are becoming an ecologically attractive alternative to gasoline driven vehicles. One drawback to them is that the associated battery chargers are power electronic circuits which, because of their non-linear nature, can produce deleterious harmonic effects on the electric utility distribution system. To investigate the harmonic effects of widespread use of EV battery chargers, three different commercially available EV battery chargers are modeled using the injection current method to represent their current waveforms for simulation in a SPICE model of a particular distribution system.

  19. Investigation of mass transfer intensification under power ultrasound irradiation using 3D computational simulation: A comparative analysis.

    PubMed

    Sajjadi, Baharak; Asgharzadehahmadi, Seyedali; Asaithambi, Perumal; Raman, Abdul Aziz Abdul; Parthasarathy, Rajarathinam

    2017-01-01

    This paper aims at investigating the influence of acoustic streaming induced by low-frequency (24kHz) ultrasound irradiation on mass transfer in a two-phase system. The main objective is to discuss the possible mass transfer improvements under ultrasound irradiation. Three analyses were conducted: i) experimental analysis of mass transfer under ultrasound irradiation; ii) comparative analysis between the results of the ultrasound assisted mass transfer with that obtained from mechanically stirring; and iii) computational analysis of the systems using 3D CFD simulation. In the experimental part, the interactive effects of liquid rheological properties, ultrasound power and superficial gas velocity on mass transfer were investigated in two different sonicators. The results were then compared with that of mechanical stirring. In the computational part, the results were illustrated as a function of acoustic streaming behaviour, fluid flow pattern, gas/liquid volume fraction and turbulence in the two-phase system and finally the mass transfer coefficient was specified. It was found that additional turbulence created by ultrasound played the most important role on intensifying the mass transfer phenomena compared to that in stirred vessel. Furthermore, long residence time which depends on geometrical parameters is another key for mass transfer. The results obtained in the present study would help researchers understand the role of ultrasound as an energy source and acoustic streaming as one of the most important of ultrasound waves on intensifying gas-liquid mass transfer in a two-phase system and can be a breakthrough in the design procedure as no similar studies were found in the existing literature.

  20. A novel modular approach to active power-line harmonic filtering in distribution systems

    NASA Astrophysics Data System (ADS)

    El Shatshat, Ramadan A.

    The objective of this research is to develop an efficient and reliable modular active harmonic filter system to realize a cost-effective solution to the harmonic problem. The proposed filter system consists of a number CSC modules, each dedicated to filter a specific harmonic of choice (Frequency-Splitting Approach). The power rating of the modules will decrease and their switching frequency will increase as the order of the harmonic to be filtered is increased. The overall switching losses are minimized due to the selected harmonic elimination and balanced a "power rating"-"switching frequency" product. Two ADALINEs are proposed as a part of the filter controller for processing the signals obtained from the power-line. One ADALINE (the Current ADALINE) extracts the fundamental and harmonic components of the distorted current. The other ADALINE (the Voltage ADALINE) estimates the line voltage. The outputs of both ADALINEs are used to construct the modulating signals of the filter modules. The proposed controller decides which CSC filter module(s) is connected to the electric grid. The automated connection of the corresponding filter module(s) is based on decision-making rules in such a way that the IEEE 519-1992 limits are not violated. The information available on the magnitude of each harmonic component allows us to select the active filter bandwidth (i.e., the highest harmonic to be suppressed). This will result in more efficiency and higher performance. The proposed controller adjusts the I dc in each CSC module according to the present magnitude of the corresponding harmonic current. This results in optimum dc-side current value and minimal converter losses. The comparison of the proposed modular active filter scheme and the conventional one converter scheme on practical use in industry is presented. This comparison shows that the proposed solution is more economical, reliable and flexible compared to conventional one. High speed and accuracy of ADALINE, self

  1. An OpenGL-based Interface to 3D PowerPoint-like Presentations of OpenGL Projects

    NASA Astrophysics Data System (ADS)

    Mokhov, Serguei A.; Song, Miao

    We present a multimedia 3D interface to powerpoint-like presentations in OpenGL. The presentations of such kind are useful to demonstrate projects or conference talks with the demonstration results of a 3D animation, effects, and others alongside the presentation 'in situ' instead of switching between a regular presentation software to the demo and back - the demo and the presentation can be one and the same, embedded together.

  2. Significant enhancement of power conversion efficiency for dye sensitized solar cell using 1D/3D network nanostructures as photoanodes

    PubMed Central

    Wang, Hao; Wang, Baoyuan; Yu, Jichao; Hu, Yunxia; Xia, Chen; Zhang, Jun; Liu, Rong

    2015-01-01

    The single–crystalline TiO2 nanorod arrays with rutile phase have attracted much attention in the dye sensitized solar cells (DSSCs) applications because of their superior chemical stability, better electron transport properties, higher refractive index and low production cost. However, it suffers from a low surface area as compared with TiO2 nanoparticle films. In order to enlarge the surface area of TiO2 nanorod arrays, the 1D nanorods/3D nanotubes sample was synthesized using a facile two-step hydrothermal process involving hydrothermal growth 1D/3D nanorods and followed by post-etching treatment. In such bi-layer structure, the oriented TiO2 nanorods layer could provide direct pathway for fast electron transportation, and the 3D nanotubes layer offers a higher surface area for dye loading, therefore, the 1D nanorods/3D nanotubes photoanode exhibited faster electron transport and higher surface area than either 1D or 3D nanostructures alone, and an highest efficiency of 7.68% was achieved for the DSSCs based on 1D nanorods/3D nanotubes photoanode with further TiCl4 treatment. PMID:25800933

  3. High-frequency AC/DC converter with unity power factor and minimum harmonic distortion

    SciTech Connect

    Wernekinch, E.R.

    1987-01-01

    The power factor is controlled by adjusting the relative position of the fundamental component of an optimized PWM-type voltage with respect to the supply voltage. Current harmonic distortion is minimized by the use of optimized firing angles for the converter at a frequency where GTO's can be used. This feature makes this approach very attractive at power levels of 100 to 600 kW. To obtain the optimized PWM pattern, a steepest descent digital computer algorithm is used. Digital-computer simulations are performed and a low-power model is constructed and tested to verify the concepts and the behavior of the model. Experimental results show that unity power factor is achieved and that the distortion in the phase currents is 10.4% at 90% of full load. This is less than achievable with sinusoidal PWM, harmonic elimination, hysteresis control, and deadbeat control for the same switching frequency.

  4. Numerical study on a 0.4 THz second harmonic gyrotron with high power

    SciTech Connect

    Chaojun, Lei; Sheng, Yu; Hongfu, Li; Yinghui, Liu; Xinjian, Niu; Qixiang, Zhao

    2013-07-15

    Terahertz and sub-terahertz science and technology are promising topics today. However, it is difficult to obtain high power source of terahertz wave. In this paper, the mode competition and beam-wave interaction in a gradually tapered cavity are studied to achieve high efficiency of a 0.4THz second harmonic gyrotron in practice. In order to attain high power and stable radiation, the TE{sub 32,5} mode is selected as the operating mode of the desired gyrotron to realize single mode oscillation. The issues of studying on the high-order mode gyrotrons are solved effectively by transforming the generalized telegraphist's equations. The efficiency and output power of the gyrotron under different conditions have been calculated by the code, which is based on the transformed equations. Consequently, the results show that single mode second harmonic radiation with power of over 150 kW at frequency of 0.4 THz could be achieved.

  5. A high efficiency C-band internally-matched harmonic tuning GaN power amplifier

    NASA Astrophysics Data System (ADS)

    Lu, Y.; Zhao, B. C.; Zheng, J. X.; Zhang, H. S.; Zheng, X. F.; Ma, X. H.; Hao, Y.; Ma, P. J.

    2016-09-01

    In this paper, a high efficiency C-band gallium nitride (GaN) internally-matched power amplifier (PA) is presented. This amplifier consists of 2-chips of self-developed GaN high-electron mobility transistors (HEMTs) with 16 mm total gate width on SiC substrate. New harmonic manipulation circuits are induced both in the input and output matching networks for high efficiency matching at fundamental and 2nd-harmonic frequency, respectively. The developed amplifier has achieved 72.1% power added efficiency (PAE) with 107.4 W output power at 5 GHz. To the best of our knowledge, this amplifier exhibits the highest PAE in C-band GaN HEMT amplifiers with over 100 W output power. Additionally, 1000 hours' aging test reveals high reliability for practical applications.

  6. Harmonic analysis of Boolean networks: determinative power and perturbations

    PubMed Central

    2013-01-01

    Consider a large Boolean network with a feed forward structure. Given a probability distribution on the inputs, can one find, possibly small, collections of input nodes that determine the states of most other nodes in the network? To answer this question, a notion that quantifies the determinative power of an input over the states of the nodes in the network is needed. We argue that the mutual information (MI) between a given subset of the inputs X={X1,...,Xn} of some node i and its associated function fi(X) quantifies the determinative power of this set of inputs over node i. We compare the determinative power of a set of inputs to the sensitivity to perturbations to these inputs, and find that, maybe surprisingly, an input that has large sensitivity to perturbations does not necessarily have large determinative power. However, for unate functions, which play an important role in genetic regulatory networks, we find a direct relation between MI and sensitivity to perturbations. As an application of our results, we analyze the large-scale regulatory network of Escherichia coli. We identify the most determinative nodes and show that a small subset of those reduces the overall uncertainty of the network state significantly. Furthermore, the network is found to be tolerant to perturbations of its inputs. PMID:23642003

  7. Multimode harmonic power measurement of 40 MW pulsed S-band klystrons

    SciTech Connect

    Fowkes, W.R.; Wu, E.S.

    1984-08-01

    An array of 12 calibrated RF electric field probes on the waveguide walls are used to sample the complex field profile at the second and third harmonics where the fundamental power is in the 40 MW range at 2856 MHx. The measured amplitude and phase signals from these are Fourier analyzed to determine with good accuracy the power in each of the many possible propagating modes.

  8. Power-Line Harmonic Radiation: Can It Significantly Affect the Earth's Radiation Belts?

    PubMed

    Thorne, R M; Tsurutani, B T

    1979-05-25

    It has been suggested that harmonic radiation from the earth's 50- and 60-hertz power transmission lines might significantly influence the distribution of electrons in the radiation belts. On the basis of observations presented here, it seems advisable to accept such a hypothesis with caution. New evidence suggests that power-line radiation does not play any major role in the nonadiabatic dynamics of radiation belt electrons.

  9. Power-line harmonic radiation - Can it significantly affect the earth's radiation belts

    NASA Technical Reports Server (NTRS)

    Thorne, R. M.; Tsurutani, B. T.

    1979-01-01

    It has been suggested that harmonic radiation from the earth's 50- and 60-hertz power transmission lines might significantly influence the distribution of electrons in the radiation belts. On the basis of observations presented here, it seems advisable to accept such a hypothesis with caution. New evidence suggests that power-line radiation does not play any major role in the nonadiabatic dynamics of radiation belt electrons.

  10. A Smart Cage With Uniform Wireless Power Distribution in 3D for Enabling Long-Term Experiments With Freely Moving Animals.

    PubMed

    Mirbozorgi, S Abdollah; Bahrami, Hadi; Sawan, Mohamad; Gosselin, Benoit

    2016-04-01

    This paper presents a novel experimental chamber with uniform wireless power distribution in 3D for enabling long-term biomedical experiments with small freely moving animal subjects. The implemented power transmission chamber prototype is based on arrays of parallel resonators and multicoil inductive links, to form a novel and highly efficient wireless power transmission system. The power transmitter unit includes several identical resonators enclosed in a scalable array of overlapping square coils which are connected in parallel to provide uniform power distribution along x and y. Moreover, the proposed chamber uses two arrays of primary resonators, facing each other, and connected in parallel to achieve uniform power distribution along the z axis. Each surface includes 9 overlapped coils connected in parallel and implemented into two layers of FR4 printed circuit board. The chamber features a natural power localization mechanism, which simplifies its implementation and ease its operation by avoiding the need for active detection and control mechanisms. A single power surface based on the proposed approach can provide a power transfer efficiency (PTE) of 69% and a power delivered to the load (PDL) of 120 mW, for a separation distance of 4 cm, whereas the complete chamber prototype provides a uniform PTE of 59% and a PDL of 100 mW in 3D, everywhere inside the chamber with a size of 27×27×16 cm(3).

  11. Computer power fathoms the depths: billion-bit data processors illuminate the subsurface. [3-D Seismic techniques

    SciTech Connect

    Ross, J.J.

    1985-01-01

    Some of the same space-age signal technology being used to track events 200 miles above the earth is helping petroleum explorationists track down oil and natural gas two miles and more down into the earth. The breakthroughs, which have come in a technique called three-dimensional seismic work, could change the complexion of exploration for oil and natural gas. Thanks to this 3-D seismic approach, explorationists can make dynamic maps of sites miles beneath the surface. Then explorationists can throw these maps on space-age computer systems and manipulate them every which way - homing in sharply on salt domes, faults, sands and traps associated with oil and natural gas. ''The 3-D seismic scene has exploded within the last two years,'' says, Peiter Tackenberg, Marathon technical consultant who deals with both domestic and international exploration. The 3-D technique has been around for more than a decade, he notes, but recent achievements in space-age computer hardware and software have unlocked its full potential.

  12. Reliability of IGBT in a STATCOM for Harmonic Compensation and Power Factor Correction

    SciTech Connect

    Gopi Reddy, Lakshmi Reddy; Tolbert, Leon M; Ozpineci, Burak; Xu, Yan; Rizy, D Tom

    2012-01-01

    With smart grid integration, there is a need to characterize reliability of a power system by including reliability of power semiconductors in grid related applications. In this paper, the reliability of IGBTs in a STATCOM application is presented for two different applications, power factor correction and harmonic elimination. The STATCOM model is developed in EMTP, and analytical equations for average conduction losses in an IGBT and a diode are derived and compared with experimental data. A commonly used reliability model is used to predict reliability of IGBT.

  13. Modified Perfect Harmonics Cancellation Control of a Grid Interfaced SPV Power Generation

    NASA Astrophysics Data System (ADS)

    Singh, B.; Shahani, D. T.; Verma, A. K.

    2015-03-01

    This paper deals with a grid interfaced solar photo voltaic (SPV) power generating system with modified perfect harmonic cancellation (MPHC) control for power quality improvement in terms of mitigation of the current harmonics, power factor correction, control of point of common coupling (PCC) voltage with reactive power compensation and load balancing in a three phase distribution system. The proposed grid interfaced SPV system consists of a SPV array, a dc-dc boost converter and a voltage source converter (VSC) used for the compensation of other connected linear and nonlinear loads at PCC. The reference grid currents are estimated using MPHC method and control signals are derived by using pulse width modulation (PWM) current controller of VSC. The SPV power is fed to the common dc bus of VSC and dc-dc boost converter using maximum power point tracking (MPPT). The dc link voltage of VSC is regulated by using dc voltage proportional integral (PI) controller. The analysis of the proposed SPV power generating system is carried out under dc/ac short circuit and severe SPV-SX and SPV-TX intrusion.

  14. Electrochemiluminescence Biosensor Based on 3-D DNA Nanomachine Signal Probe Powered by Protein-Aptamer Binding Complex for Ultrasensitive Mucin 1 Detection.

    PubMed

    Jiang, Xinya; Wang, Haijun; Wang, Huijun; Zhuo, Ying; Yuan, Ruo; Chai, Yaqin

    2017-04-04

    Herein, we fabricated a novel electrochemiluminescence (ECL) biosensor for ultrasensitive detection of mucin 1 (MUC1) based on a three-dimensional (3-D) DNA nanomachine signal probe powered by protein-aptamer binding complex. The assembly of 3-D DNA nanomachine signal probe achieved the cyclic reuse of target protein based on the protein-aptamer binding complex induced catalyzed hairpin assembly (CHA), which overcame the shortcoming of protein conversion with enzyme cleavage or polymerization in the traditional examination of protein. In addition, CoFe2O4, a mimic peroxidase, was used as the nanocarrier of the 3-D DNA nanomachine signal probe to catalyze the decomposition of coreactant H2O2 to generate numerous reactive hydroxyl radical OH(•) as the efficient accelerator of N-(aminobutyl)-N-(ethylisoluminol) (ABEI) ECL reaction to amplify the luminescence signal. Simultaneously, the assembly of 3-D DNA nanomachine signal probe was executed in solution, which led to abundant luminophore ABEI be immobilized around the CoFe2O4 surface with amplified ECL signal output since the CHA reaction was occurred unencumberedly in all directions under homogeneous environment. The prepared ECL biosensor showed a favorable linear response for MUC1 detection with a relatively low detection limit of 0.62 fg mL(-1). With excellent sensitivity, the strategy may provide an efficient method for clinical application, especially in trace protein determination.

  15. Generalized power-spectrum Larmor formula for an extended charged particle embedded in a harmonic oscillator

    NASA Astrophysics Data System (ADS)

    Marengo, Edwin A.; Khodja, Mohamed R.

    2006-09-01

    The nonrelativistic Larmor radiation formula, giving the power radiated by an accelerated charged point particle, is generalized for a spatially extended particle in the context of the classical charged harmonic oscillator. The particle is modeled as a spherically symmetric rigid charge distribution that possesses both translational and spinning degrees of freedom. The power spectrum obtained exhibits a structure that depends on the form factor of the particle, but reduces, in the limit of an infinitesimally small particle and for the charge distributions considered, to Larmor’s familiar result. It is found that for finite-duration small-enough accelerations as well as perpetual uniform accelerations the power spectrum of the spatially extended particle reduces to that of a point particle. It is also found that when the acceleration is violent or the size parameter of the particle is very large compared to the wavelength of the emitted radiation the power spectrum is highly suppressed. Possible applications are discussed.

  16. Inverse-power-law behavior of cellular motility reveals stromal–epithelial cell interactions in 3D co-culture by OCT fluctuation spectroscopy

    PubMed Central

    Oldenburg, Amy L.; Yu, Xiao; Gilliss, Thomas; Alabi, Oluwafemi; Taylor, Russell M.; Troester, Melissa A.

    2015-01-01

    The progression of breast cancer is known to be affected by stromal cells within the local microenvironment. Here we study the effect of stromal fibroblasts on the in-place motions (motility) of mammary epithelial cells within organoids in 3D co-culture, inferred from the speckle fluctuation spectrum using optical coherence tomography (OCT). In contrast to Brownian motion, mammary cell motions exhibit an inverse power-law fluctuation spectrum. We introduce two complementary metrics for quantifying fluctuation spectra: the power-law exponent and a novel definition of the motility amplitude, both of which are signal- and position-independent. We find that the power-law exponent and motility amplitude are positively (p<0.001) and negatively (p<0.01) correlated with the density of stromal cells in 3D co-culture, respectively. We also show how the hyperspectral data can be visualized using these metrics to observe heterogeneity within organoids. This constitutes a simple and powerful tool for detecting and imaging cellular functional changes with OCT. PMID:26973862

  17. Evaluation of Freehand B-Mode and Power-Mode 3D Ultrasound for Visualisation and Grading of Internal Carotid Artery Stenosis

    PubMed Central

    Karlas, Thomas; Saur, Dorothee

    2017-01-01

    Background Currently, colour-coded duplex sonography (2D-CDS) is clinical standard for detection and grading of internal carotid artery stenosis (ICAS). However, unlike angiographic imaging modalities, 2D-CDS assesses ICAS by its hemodynamic effects rather than luminal changes. Aim of this study was to evaluate freehand 3D ultrasound (3DUS) for direct visualisation and quantification of ICAS. Methods Thirty-seven patients with 43 ICAS were examined with 2D-CDS as reference standard and with freehand B-mode respectively power-mode 3DUS. Stenotic value of 3D reconstructed ICAS was calculated as distal diameter respectively distal cross-sectional area (CSA) reduction percentage and compared with 2D-CDS. Results There was a trend but no significant difference in successful 3D reconstruction of ICAS between B-mode and power mode (examiner 1 {Ex1} 81% versus 93%, examiner 2 {Ex2} 84% versus 88%). Inter-rater agreement was best for power-mode 3DUS and assessment of stenotic value as distal CSA reduction percentage (intraclass correlation coefficient {ICC} 0.90) followed by power-mode 3DUS and distal diameter reduction percentage (ICC 0.81). Inter-rater agreement was poor for B-mode 3DUS (ICC, distal CSA reduction 0.36, distal diameter reduction 0.51). Intra-rater agreement for power-mode 3DUS was good for both measuring methods (ICC, distal CSA reduction 0.88 {Ex1} and 0.78 {Ex2}; ICC, distal diameter reduction 0.83 {Ex1} and 0.76 {Ex2}). In comparison to 2D-CDS inter-method agreement was good and clearly better for power-mode 3DUS (ICC, distal diameter reduction percentage: Ex1 0.85, Ex2 0.78; distal CSA reduction percentage: Ex1 0.63, Ex2 0.57) than for B-mode 3DUS (ICC, distal diameter reduction percentage: Ex1 0.40, Ex2 0.52; distal CSA reduction percentage: Ex1 0.15, Ex2 0.51). Conclusions Non-invasive power-mode 3DUS is superior to B-mode 3DUS for imaging and quantification of ICAS. Thereby, further studies are warranted which should now compare power-mode 3DUS with

  18. Improving the -3 dB bandwidth of medium power GaN-based LEDs through periodic micro via-holes for visible light communications

    NASA Astrophysics Data System (ADS)

    Zhou, Zheng; Yan, Bing; Teng, Dongdong; Liu, Lilin; Wang, Gang

    2017-06-01

    Medium power GaN-based light emitting diode (LED) chips with periodic micro via-holes are designed and fabricated. The active area of each chip is 200 μm×800 μm and the diameter of each micro via-hole is 50 μm. For comparison, an LED chip with only one big via-hole (Diameter=86.6 μm) is also fabricated under the same conditions as the control partner. Both kinds of LED chips have an equal effective PN junction area. Experimentally, the LED with periodic via-holes exhibits higher output optical power and the -3 dB modulation bandwidth by about 33% and 48%, respectively, than the LED with only one bigger via-hole. The method of concurrently improving modulation and optical performances of power-type LED chips through periodic micro via-holes take the advantages of easy fabrication, suitable for mass-production.

  19. Analysis of dc harmonics using the three-pulse model for the intermountain power project HVDC transmission

    SciTech Connect

    Dickmander, D.L.; Peterson, K.J.

    1989-04-01

    The harmonic analysis of the dc-side of an HVDC line transmission requires realistic models of the converters, the dc line, and other relevant equipment. These models must include all important paths for harmonic current, and appropriate sources of harmonic voltage generation. The classical converter modeling technique has been demonstrated to be insufficient in field measurements and analysis of the harmonic spectra found on recent HVDC line transmission. For this reason, a new model of the converter bridge which takes into account the major stray capacitances in the converter (the three-pulse model) has been developed, and is described in detail elsewhere. This paper presents comparisons between the classical and three-pulse calculations for the Intermountain Power Project (IPP) HVDC transmission. The calculation results from the three-pulse model agree favorably with the harmonics found in field measurements.

  20. Low-power analog processing for sensing applications: low-frequency harmonic signal classification.

    PubMed

    White, Daniel J; William, Peter E; Hoffman, Michael W; Balkir, Sina

    2013-07-25

    A low-power analog sensor front-end is described that reduces the energy required to extract environmental sensing spectral features without using Fast Fouriér Transform (FFT) or wavelet transforms. An Analog Harmonic Transform (AHT) allows selection of only the features needed by the back-end, in contrast to the FFT, where all coefficients must be calculated simultaneously. We also show that the FFT coefficients can be easily calculated from the AHT results by a simple back-substitution. The scheme is tailored for low-power, parallel analog implementation in an integrated circuit (IC). Two different applications are tested with an ideal front-end model and compared to existing studies with the same data sets. Results from the military vehicle classification and identification of machine-bearing fault applications shows that the front-end suits a wide range of harmonic signal sources. Analog-related errors are modeled to evaluate the feasibility of and to set design parameters for an IC implementation to maintain good system-level performance. Design of a preliminary transistor-level integrator circuit in a 0.13 µm complementary metal-oxide-silicon (CMOS) integrated circuit process showed the ability to use online self-calibration to reduce fabrication errors to a sufficiently low level. Estimated power dissipation is about three orders of magnitude less than similar vehicle classification systems that use commercially available FFT spectral extraction.

  1. Extremum seeking x-ray position feedback using power line harmonic leakage as the perturbation

    NASA Astrophysics Data System (ADS)

    Zohar, S.; Kissick, D. J.; Venugopalan, N.; Ogata, C. M.; Makarov, O.; Stepanov, S.; Fischetti, R. F.

    2016-09-01

    Small x-ray beam sizes necessary for probing nanoscale phenomena require exquisite stability to prevent data corruption by noise. One source of instability at synchrotron radiation x-ray beamlines is the slow detuning of x-ray optics to marginal alignment where the onset of clipping increases the beam's susceptibility to higher frequency position oscillations. In this article, we show that a 1 μ m amplitude horizontal x-ray beam oscillation driven by power line harmonic leakage into the electron storage ring can be used as perturbation for horizontal position extremum seeking feedback. Feedback performance is characterized by convergence to 1.5% away from maximum intensity at optimal alignment.

  2. Effect of Power Line Interference on Microphone Calibration Measurements Made at or Near Harmonics of the Power Line Frequency.

    PubMed

    Wagner, Randall P; Nedzelnitsky, Victor

    2007-01-01

    The electrical measurements required during the primary calibrations of laboratory standard microphones by the reciprocity method can be influenced by power line interference. Because of this influence, the protocols of international inter-laboratory key comparisons of microphone calibrations usually have not included measurements at power line frequencies. Such interference has been observed in microphone output voltage measurements made with a microphone pressure reciprocity calibration system under development at NIST. This system was configured for a particular type of standard microphone in such a way that measurements of relatively small signal levels, which are more susceptible to the effect of power line interference, were required. This effect was investigated by acquiring microphone output voltage measurement data with the power line frequency adjusted to move the frequency of the interference relative to the center frequency of the measurement system passband. These data showed that the effect of power line interference for this system configuration can be more than one percent at test frequencies harmonically related to the power line frequency. These data also showed that adjusting the power line frequency to separate the interference and test frequencies by as little as 1.0 Hz can reduce the effect of the interference by at least an order of magnitude. Adjustment of the power line frequency could enable accurate measurements at test frequencies that otherwise might be avoided.

  3. Solid-liquid phase transitions in 3D systems with the inverse-power and Yukawa potentials

    NASA Astrophysics Data System (ADS)

    Vaulina, O. S.; Koss, X. G.

    2016-03-01

    The melting of face-centered cubic (fcc) and body-centered cubic (bcc) crystal lattices was studied analytically and numerically for the systems of particles interacting via the inverse-power-law and Yukawa potentials. New approach is proposed for determination of the solid-liquid phase transitions in these systems. The suggested approach takes into account a nonlinearity (anharmonicity) of pair interaction forces and allows to correctly predict the conditions of melting of the systems with various isotropic pair interaction potentials. The obtained results are compared with the existing theoretical and numerical data.

  4. Highly-Ordered 3D Vertical Resistive Switching Memory Arrays with Ultralow Power Consumption and Ultrahigh Density.

    PubMed

    Al-Haddad, Ahmed; Wang, Chengliang; Qi, Haoyuan; Grote, Fabian; Wen, Liaoyong; Bernhard, Jörg; Vellacheri, Ranjith; Tarish, Samar; Nabi, Ghulam; Kaiser, Ute; Lei, Yong

    2016-09-07

    Resistive switching random access memories (RRAM) have attracted great scientific and industrial attention for next generation data storage because of their advantages of nonvolatile properties, high density, low power consumption, fast writing/erasing speed, good endurance, and simple and small operation system. Here, by using a template-assisted technique, we demonstrate a three-dimensional highly ordered vertical RRAM device array with density as high as that of the nanopores of the template (10(8)-10(9) cm(-2)), which can also be fabricated in large area. The high crystallinity of the materials, the large contact area and the intimate semiconductor/electrode interface (3 nm interfacial layer) make the ultralow voltage operation (millivolt magnitude) and ultralow power consumption (picowatt) possible. Our procedure for fabrication of the nanodevice arrays in large area can be used for producing many other different materials and such three-dimensional electronic device arrays with the capability to adjust the device densities can be extended to other applications of the next generation nanodevice technology.

  5. A Comprehensive 3D Finite Element Model of a Thermoelectric Module Used in a Power Generator: A Transient Performance Perspective

    NASA Astrophysics Data System (ADS)

    Wu, Guangxi; Yu, Xiong

    2015-06-01

    Thermoelectric power generator has potential for small-scale and distributed power generation because of its high durability and scalability. It is very important to realize that the transient behavior of thermoelectric modules (TEM) affects a thermoelectric generator's response to dynamic working environments. Traditionally, researchers have used simplified models to describe the behavior of thermoelectric modules. In this paper we propose a comprehensive mathematical model that considers the effect of variations of chemical potential and carrier density, which are ignored by traditional models. Finite element models based on this new model are used to simulate the transient behavior of a thermoelectric module subjected to rapid changes in boundary temperature or working load. Simulation results show that transition times of thermoelectric modules affected by temperature change are much longer than those of modules affected by changes in electrical load resistance. Sudden changes in working temperature cause voltage overshoot of the TEM output, which, however, is not observed in responses to sudden changes of load resistance. Comparisons also show there are significant differences between the behavior of TEM predicted by use of this new comprehensive model and that predicted by use of traditional models, particularly for the high-temperature intrinsic ionization region and the low-temperature weak ionization region. This implies that chemical potential and carrier density variations, which are taken into account by this new model but ignored by traditional models, have major effects on the performance of TEM.

  6. Cryogenic Yb:YAG picosecond laser with high average power visible and ultraviolet harmonic generation

    NASA Astrophysics Data System (ADS)

    Brown, D. C.; Kowalewski, K.; Envid, V.; Zembek, J.; Canale, B.; Kolis, J. W.; McMillen, C. D.; Geisber, H.

    2012-06-01

    Cryogenic Yb:YAG lasers operating at 1029 nm have been demonstrated at Snake Creek Lasers with high average power CW and ultrafast output powers, and provide near diffraction-limited output beams that are ideal for applications in harmonic generation. We describe experiments that have produced high average power green output power at 515 nm as well as preliminary experiments producing UV output power at 257.25 nm. Frequency doubling experiments used a 20 mm long non-critically phase-matched LBO crystal mounted in a constant temperature oven. A mode-locked Yb fiber laser operating at 50 MHz was used to drive a two Yb:YAG cryogenic amplifier system, producing hundreds of watts of average power output with a FWHM pulsewidth of 12 ps. Doubling efficiencies of > 50 % have been observed. For frequency quadrupling, we have used hydrothermally grown KTTP crystals grown at Clemson University and Advanced Photonic Crystals. KBBF offers unprecedented UV transmission down to 155 nm, and was used in a Type I phasematching configuration. The properties of KBBF will be discussed, as well as the experimental results observed and conversion efficiency.

  7. Influence of ultrasound power on acoustic streaming and micro-bubbles formations in a low frequency sono-reactor: mathematical and 3D computational simulation.

    PubMed

    Sajjadi, Baharak; Raman, Abdul Aziz Abdul; Ibrahim, Shaliza

    2015-05-01

    This paper aims at investigating the influence of ultrasound power amplitude on liquid behaviour in a low-frequency (24 kHz) sono-reactor. Three types of analysis were employed: (i) mechanical analysis of micro-bubbles formation and their activities/characteristics using mathematical modelling. (ii) Numerical analysis of acoustic streaming, fluid flow pattern, volume fraction of micro-bubbles and turbulence using 3D CFD simulation. (iii) Practical analysis of fluid flow pattern and acoustic streaming under ultrasound irradiation using Particle Image Velocimetry (PIV). In mathematical modelling, a lone micro bubble generated under power ultrasound irradiation was mechanistically analysed. Its characteristics were illustrated as a function of bubble radius, internal temperature and pressure (hot spot conditions) and oscillation (pulsation) velocity. The results showed that ultrasound power significantly affected the conditions of hotspots and bubbles oscillation velocity. From the CFD results, it was observed that the total volume of the micro-bubbles increased by about 4.95% with each 100 W-increase in power amplitude. Furthermore, velocity of acoustic streaming increased from 29 to 119 cm/s as power increased, which was in good agreement with the PIV analysis.

  8. 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.

  9. Resolution-Enhanced Harmonic and Interharmonic Measurement for Power Quality Analysis in Cyber-Physical Energy System

    PubMed Central

    Liu, Yanchi; Wang, Xue; Liu, Youda; Cui, Sujin

    2016-01-01

    Power quality analysis issues, especially the measurement of harmonic and interharmonic in cyber-physical energy systems, are addressed in this paper. As new situations are introduced to the power system, the impact of electric vehicles, distributed generation and renewable energy has introduced extra demands to distributed sensors, waveform-level information and power quality data analytics. Harmonics and interharmonics, as the most significant disturbances, require carefully designed detection methods for an accurate measurement of electric loads whose information is crucial to subsequent analyzing and control. This paper gives a detailed description of the power quality analysis framework in networked environment and presents a fast and resolution-enhanced method for harmonic and interharmonic measurement. The proposed method first extracts harmonic and interharmonic components efficiently using the single-channel version of Robust Independent Component Analysis (RobustICA), then estimates the high-resolution frequency from three discrete Fourier transform (DFT) samples with little additional computation, and finally computes the amplitudes and phases with the adaptive linear neuron network. The experiments show that the proposed method is time-efficient and leads to a better accuracy of the simulated and experimental signals in the presence of noise and fundamental frequency deviation, thus providing a deeper insight into the (inter)harmonic sources or even the whole system. PMID:27355946

  10. Resolution-Enhanced Harmonic and Interharmonic Measurement for Power Quality Analysis in Cyber-Physical Energy System.

    PubMed

    Liu, Yanchi; Wang, Xue; Liu, Youda; Cui, Sujin

    2016-06-27

    Power quality analysis issues, especially the measurement of harmonic and interharmonic in cyber-physical energy systems, are addressed in this paper. As new situations are introduced to the power system, the impact of electric vehicles, distributed generation and renewable energy has introduced extra demands to distributed sensors, waveform-level information and power quality data analytics. Harmonics and interharmonics, as the most significant disturbances, require carefully designed detection methods for an accurate measurement of electric loads whose information is crucial to subsequent analyzing and control. This paper gives a detailed description of the power quality analysis framework in networked environment and presents a fast and resolution-enhanced method for harmonic and interharmonic measurement. The proposed method first extracts harmonic and interharmonic components efficiently using the single-channel version of Robust Independent Component Analysis (RobustICA), then estimates the high-resolution frequency from three discrete Fourier transform (DFT) samples with little additional computation, and finally computes the amplitudes and phases with the adaptive linear neuron network. The experiments show that the proposed method is time-efficient and leads to a better accuracy of the simulated and experimental signals in the presence of noise and fundamental frequency deviation, thus providing a deeper insight into the (inter)harmonic sources or even the whole system.

  11. Life Cycle Greenhouse Gas Emissions of Utility-Scale Wind Power: Systematic Review and Harmonization

    SciTech Connect

    Dolan, S. L.; Heath, G. A.

    2012-04-01

    A systematic review and harmonization of life cycle assessment (LCA) literature of utility-scale wind power systems was performed to determine the causes of and, where possible, reduce variability in estimates of life cycle greenhouse gas (GHG) emissions. Screening of approximately 240 LCAs of onshore and offshore systems yielded 72 references meeting minimum thresholds for quality, transparency, and relevance. Of those, 49 references provided 126 estimates of life cycle GHG emissions. Published estimates ranged from 1.7 to 81 grams CO{sub 2}-equivalent per kilowatt-hour (g CO{sub 2}-eq/kWh), with median and interquartile range (IQR) both at 12 g CO{sub 2}-eq/kWh. After adjusting the published estimates to use consistent gross system boundaries and values for several important system parameters, the total range was reduced by 47% to 3.0 to 45 g CO{sub 2}-eq/kWh and the IQR was reduced by 14% to 10 g CO{sub 2}-eq/kWh, while the median remained relatively constant (11 g CO{sub 2}-eq/kWh). Harmonization of capacity factor resulted in the largest reduction in variability in life cycle GHG emission estimates. This study concludes that the large number of previously published life cycle GHG emission estimates of wind power systems and their tight distribution suggest that new process-based LCAs of similar wind turbine technologies are unlikely to differ greatly. However, additional consequential LCAs would enhance the understanding of true life cycle GHG emissions of wind power (e.g., changes to other generators operations when wind electricity is added to the grid), although even those are unlikely to fundamentally change the comparison of wind to other electricity generation sources.

  12. Harmonic Resonance in Power Transmission Systems due to the Addition of Shunt Capacitors

    NASA Astrophysics Data System (ADS)

    Patil, Hardik U.

    Shunt capacitors are often added in transmission networks at suitable locations to improve the voltage profile. In this thesis, the transmission system in Arizona is considered as a test bed. Many shunt capacitors already exist in the Arizona transmission system and more are planned to be added. Addition of these shunt capacitors may create resonance conditions in response to harmonic voltages and currents. Such resonance, if it occurs, may create problematic issues in the system. It is main objective of this thesis to identify potential problematic effects that could occur after placing new shunt capacitors at selected buses in the Arizona network. Part of the objective is to create a systematic plan for avoidance of resonance issues. For this study, a method of capacitance scan is proposed. The bus admittance matrix is used as a model of the networked transmission system. The calculations on the admittance matrix were done using Matlab. The test bed is the actual transmission system in Arizona; however, for proprietary reasons, bus names are masked in the thesis copy intended for the public domain. The admittance matrix was obtained from data using the PowerWorld Simulator after equivalencing the 2016 summer peak load (planning case). The full Western Electricity Coordinating Council (WECC) system data were used. The equivalencing procedure retains only the Arizona portion of the WECC. The capacitor scan results for single capacitor placement and multiple capacitor placement cases are presented. Problematic cases are identified in the form of 'forbidden response. The harmonic voltage impact of known sources of harmonics, mainly large scale HVDC sources, is also presented. Specific key results for the study indicated include: (1) The forbidden zones obtained as per the IEEE 519 standard indicates the bus 10 to be the most problematic bus. (2) The forbidden zones also indicate that switching values for the switched shunt capacitor (if used) at bus 3 should be

  13. Introduction to macroscopic power scaling principles for high-order harmonic generation

    NASA Astrophysics Data System (ADS)

    Heyl, C. M.; Arnold, C. L.; Couairon, A.; L'Huillier, A.

    2017-01-01

    This tutorial presents an introduction to power scaling concepts for high-order harmonic generation (HHG) and attosecond pulse production. We present an overview of state-of-the-art HHG-based extreme ultraviolet (XUV) sources, followed by a brief introduction to basic principles underlying HHG and a detailed discussion of macroscopic effects and scaling principles. Particular emphasis is put on a general scaling model that allows the invariant scaling of the HHG process both, to μJ-level driving laser pulses and thus to multi-MHz repetition rates as well as to 100 mJ-or even Joule-level laser pulses, allowing new intensity regimes with attosecond XUV pulses.

  14. 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.

  15. Development of a single-phase harmonic power flow program to study the 20 kHz AC power system for large spacecraft

    NASA Technical Reports Server (NTRS)

    Kraft, L. Alan; Kankam, M. David

    1991-01-01

    The development of software is described to aid in design and analysis of AC power systems for large spacecraft. The algorithm is an important version of harmonic power flow program, HARMFLO, used for the study of AC power quality. The new program is applicable to three-phase systems typified by terrestrial power systems, and single-phase systems characteristic of space power systems. The modified HARMFLO accommodates system operating frequencies ranging from terrestrial 60 Hz to and beyond aerospace 20 kHz, and can handle both source and load-end harmonic distortions. Comparison of simulation and test results of a representative spacecraft power system shows a satisfactory correlation. Recommendations are made for the direction of future improvements to the software, to enhance its usefulness to power system designer and analysts.

  16. Definitions of non-stationary vibration power for time-frequency analysis and computational algorithms based upon harmonic wavelet transform

    NASA Astrophysics Data System (ADS)

    Heo, YongHwa; Kim, Kwang-joon

    2015-02-01

    While the vibration power for a set of harmonic force and velocity signals is well defined and known, it is not as popular yet for a set of stationary random force and velocity processes, although it can be found in some literatures. In this paper, the definition of the vibration power for a set of non-stationary random force and velocity signals will be derived for the purpose of a time-frequency analysis based on the definitions of the vibration power for the harmonic and stationary random signals. The non-stationary vibration power, defined as the short-time average of the product of the force and velocity over a given frequency range of interest, can be calculated by three methods: the Wigner-Ville distribution, the short-time Fourier transform, and the harmonic wavelet transform. The latter method is selected in this paper because band-pass filtering can be done without phase distortions, and the frequency ranges can be chosen very flexibly for the time-frequency analysis. Three algorithms for the time-frequency analysis of the non-stationary vibration power using the harmonic wavelet transform are discussed. The first is an algorithm for computation according to the full definition, while the others are approximate. Noting that the force and velocity decomposed into frequency ranges of interest by the harmonic wavelet transform are constructed with coefficients and basis functions, for the second algorithm, it is suggested to prepare a table of time integrals of the product of the basis functions in advance, which are independent of the signals under analysis. How to prepare and utilize the integral table are presented. The third algorithm is based on an evolutionary spectrum. Applications of the algorithms to the time-frequency analysis of the vibration power transmitted from an excitation source to a receiver structure in a simple mechanical system consisting of a cantilever beam and a reaction wheel are presented for illustration.

  17. 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?

  18. 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.

  19. Enhanced second-harmonic generation by means of high-power confinement in a photovoltaic soliton-induced waveguide.

    PubMed

    Lou, Cibo; Xu, Jingjun; Qiao, Haijun; Zhang, Xinzheng; Chen, Yunlin; Chen, Zhigang

    2004-05-01

    We present the first experimental demonstration of enhanced second-harmonic generation (SHG) by means of power confinement with a femtosecond laser in a photovoltaic soliton-induced waveguide. A dark spatial soliton created with a weak cw laser beam in a photovoltaic lithium niobate crystal induces an efficient waveguide for SHG, leading to a 60% enhancement of the conversion efficiency.

  20. Harmonic analysis of GaN-HEMTs at different temperatures and frequencies using Volterra power series

    NASA Astrophysics Data System (ADS)

    Yıldırım, Remzi; Karaarslan, Ahmet

    2015-02-01

    In this study, the detailed harmonic analysis of GaN high electron mobility transistor (HEMT) at different temperatures and frequencies is presented. Volterra power series and multi-dimensional Laplace transform are used as a method. The Volterra power series is also solved up to third degree, and the small signal transfer functions of kernels (H1, H2 and H3) are obtained. The relationship between drain inductance (Ld), gate-source voltage (Vgs), impedance (ZL) and the effect of frequency (Fr) to the output gain is identified. Besides, the nonlinear gains of H1, H2 and H3 kernels of the GaN-HEMT are obtained. The inverse relationship between the output gains of H1, H2 and H3 kernels are derived. An unsuitable situation has also been identified for sub-carrier inter-modulation systems. In addition, an asymmetric structure is also obtained between the output gain of H2 and side-band frequencies. The effects of other parameters are carried out for the output gain.

  1. Depolarization of radiation from high-power neodymium lasers and second harmonic generation of partly depolarized radiation

    SciTech Connect

    Arifzhanov, S.B.; Gulamov, A.A.; Redkorechev, V.I.; Usmanov, T.

    1985-07-01

    A theoretical analysis is made of two mechanisms (linear and nonlinear) of depolarization of radiation emitted by high-power solid-state glass lasers: these mechanisms are anisotropy-induced in the active elements and a nonlinear rotation of the polarization ellipse. In the cases of linear and circular polarization of practical interest, a qualitative and numerical analysis is made of the influence of depolarization of the radiation on second harmonic generation by the second type of interaction in KDP crystals. It is shown that in a field of partly depolarized radiation the second harmonic generation efficiency is limited mainly by depolarization of the radiation.

  2. 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)

  3. Life Cycle Greenhouse Gas Emissions of Trough and Tower Concentrating Solar Power Electricity Generation: Systematic Review and Harmonization

    SciTech Connect

    Burkhardt, J. J.; Heath, G.; Cohen, E.

    2012-04-01

    In reviewing life cycle assessment (LCA) literature of utility-scale concentrating solar power (CSP) systems, this analysis focuses on reducing variability and clarifying the central tendency of published estimates of life cycle greenhouse gas (GHG) emissions through a meta-analytical process called harmonization. From 125 references reviewed, 10 produced 36 independent GHG emissions estimates passing screens for quality and relevance: 19 for parabolic trough (trough) technology and 17 for power tower (tower) technology. The interquartile range (IQR) of published estimates for troughs and towers were 83 and 20 grams of carbon dioxide equivalent per kilowatt-hour (g CO2-eq/kWh),1 respectively; median estimates were 26 and 38 g CO2-eq/kWh for trough and tower, respectively. Two levels of harmonization were applied. Light harmonization reduced variability in published estimates by using consistent values for key parameters pertaining to plant design and performance. The IQR and median were reduced by 87% and 17%, respectively, for troughs. For towers, the IQR and median decreased by 33% and 38%, respectively. Next, five trough LCAs reporting detailed life cycle inventories were identified. The variability and central tendency of their estimates are reduced by 91% and 81%, respectively, after light harmonization. By harmonizing these five estimates to consistent values for global warming intensities of materials and expanding system boundaries to consistently include electricity and auxiliary natural gas combustion, variability is reduced by an additional 32% while central tendency increases by 8%. These harmonized values provide useful starting points for policy makers in evaluating life cycle GHG emissions from CSP projects without the requirement to conduct a full LCA for each new project.

  4. 3D weak lensing with spin wavelets on the ball

    NASA Astrophysics Data System (ADS)

    Leistedt, Boris; McEwen, Jason D.; Kitching, Thomas D.; Peiris, Hiranya V.

    2015-12-01

    We construct the spin flaglet transform, a wavelet transform to analyze spin signals in three dimensions. Spin flaglets can probe signal content localized simultaneously in space and frequency and, moreover, are separable so that their angular and radial properties can be controlled independently. They are particularly suited to analyzing cosmological observations such as the weak gravitational lensing of galaxies. Such observations have a unique 3D geometrical setting since they are natively made on the sky, have spin angular symmetries, and are extended in the radial direction by additional distance or redshift information. Flaglets are constructed in the harmonic space defined by the Fourier-Laguerre transform, previously defined for scalar functions and extended here to signals with spin symmetries. Thanks to various sampling theorems, both the Fourier-Laguerre and flaglet transforms are theoretically exact when applied to bandlimited signals. In other words, in numerical computations the only loss of information is due to the finite representation of floating point numbers. We develop a 3D framework relating the weak lensing power spectrum to covariances of flaglet coefficients. We suggest that the resulting novel flaglet weak lensing estimator offers a powerful alternative to common 2D and 3D approaches to accurately capture cosmological information. While standard weak lensing analyses focus on either real- or harmonic-space representations (i.e., correlation functions or Fourier-Bessel power spectra, respectively), a wavelet approach inherits the advantages of both techniques, where both complicated sky coverage and uncertainties associated with the physical modeling of small scales can be handled effectively. Our codes to compute the Fourier-Laguerre and flaglet transforms are made publicly available.

  5. High-harmonic fast-wave power flow along magnetic field lines in the scrape-off layer of NSTX.

    PubMed

    Perkins, R J; Hosea, J C; Kramer, G J; Ahn, J-W; Bell, R E; Diallo, A; Gerhardt, S; Gray, T K; Green, D L; Jaeger, E F; Jaworski, M A; LeBlanc, B P; McLean, A; Maingi, R; Phillips, C K; Roquemore, L; Ryan, P M; Sabbagh, S; Taylor, G; Wilson, J R

    2012-07-27

    A significant fraction of high-harmonic fast-wave (HHFW) power applied to NSTX can be lost to the scrape-off layer (SOL) and deposited in bright and hot spirals on the divertor rather than in the core plasma. We show that the HHFW power flows to these spirals along magnetic field lines passing through the SOL in front of the antenna, implying that the HHFW power couples across the entire width of the SOL rather than mostly at the antenna face. This result will help guide future efforts to understand and minimize these edge losses in order to maximize fast-wave heating and current drive.

  6. Full wave simulations of fast wave efficiency and power losses in the scrape-off layer of tokamak plasmas in mid/high harmonic and minority heating regimes

    SciTech Connect

    Bertelli, N.; Jaeger, E. F.; Hosea, J. C.; Phillips, C. K.; Berry, L.; Bonoli, P. T.; Gerhardt, S. P.; Green, D.; LeBlanc, B.; Perkins, R. J.; Qin, C. M.; Pinsker, R. I.; Prater, R.; Ryan, P. M.; Taylor, G.; Valeo, E. J.; Wilson, J. R.; Wright, J. C.; Zhang, X. J.

    2015-12-17

    Here, several experiments on different machines and in different fast wave (FW) heating regimes, such as hydrogen minority heating and high harmonic fast waves (HHFW), have found strong interaction between radio-frequency (RF) waves and the scrape-off layer (SOL) region. This paper examines the propagation and the power loss in the SOL by using the full wave code AORSA, in which the edge plasma beyond the last closed flux surface (LCFS) is included in the solution domain and a collisional damping parameter is used as a proxy to represent the real, and most likely nonlinear, damping processes. 2D and 3D AORSA results for the National Spherical Torus eXperiment (NSTX) have shown a strong transition to higher SOL power losses (driven by the RF field) when the FW cut-off is removed from in front of the antenna by increasing the edge density. Here, full wave simulations have been extended for 'conventional' tokamaks with higher aspect ratios, such as the DIII-D, Alcator C-Mod, and EAST devices. DIII-D results in HHFW regime show similar behavior found in NSTX and NSTX-U, consistent with previous DIII-D experimental observations. In contrast, a different behavior has been found for C-Mod and EAST, which operate in the minority heating regime.

  7. Full wave simulations of fast wave efficiency and power losses in the scrape-off layer of tokamak plasmas in mid/high harmonic and minority heating regimes

    DOE PAGES

    Bertelli, N.; Jaeger, E. F.; Hosea, J. C.; ...

    2015-12-17

    Here, several experiments on different machines and in different fast wave (FW) heating regimes, such as hydrogen minority heating and high harmonic fast waves (HHFW), have found strong interaction between radio-frequency (RF) waves and the scrape-off layer (SOL) region. This paper examines the propagation and the power loss in the SOL by using the full wave code AORSA, in which the edge plasma beyond the last closed flux surface (LCFS) is included in the solution domain and a collisional damping parameter is used as a proxy to represent the real, and most likely nonlinear, damping processes. 2D and 3D AORSAmore » results for the National Spherical Torus eXperiment (NSTX) have shown a strong transition to higher SOL power losses (driven by the RF field) when the FW cut-off is removed from in front of the antenna by increasing the edge density. Here, full wave simulations have been extended for 'conventional' tokamaks with higher aspect ratios, such as the DIII-D, Alcator C-Mod, and EAST devices. DIII-D results in HHFW regime show similar behavior found in NSTX and NSTX-U, consistent with previous DIII-D experimental observations. In contrast, a different behavior has been found for C-Mod and EAST, which operate in the minority heating regime.« less

  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. Noise characterization of mode-locked lasers by comparing the power spectra of the fundamental and second-harmonic pulses

    NASA Astrophysics Data System (ADS)

    Wang, Yong; Chen, L. P.; Liu, J. M.

    1995-10-01

    By comparing the noise power spectra of the fundamental pulses and those of the second-harmonic pulses, the peak intensity fluctuation, the pulse-width fluctuation, the pulse timing jitter, and the cross correlation between the pulse width and the peak intensity fluctuations of a mode-locked pulse train can be separately quantified. The noise characteristics of an actively mode-locked Nd:YLF laser are presented to demonstrate this technique.

  10. Analytical and numerical prediction of harmonic sound power in the inlet of aero-engines with emphasis on transonic rotation speeds

    NASA Astrophysics Data System (ADS)

    Lewy, Serge; Polacsek, Cyril; Barrier, Raphael

    2014-12-01

    Tone noise radiated through the inlet of a turbofan is mainly due to rotor-stator interactions at subsonic regimes (approach flight), and to the shock waves attached to each blade at supersonic helical tip speeds (takeoff). The axial compressor of a helicopter turboshaft engine is transonic as well and can be studied like turbofans at takeoff. The objective of the paper is to predict the sound power at the inlet radiating into the free field, with a focus on transonic conditions because sound levels are much higher. Direct numerical computation of tone acoustic power is based on a RANS (Reynolds averaged Navier-Stokes) solver followed by an integration of acoustic intensity over specified inlet cross-sections, derived from Cantrell and Hart equations (valid in irrotational flows). In transonic regimes, sound power decreases along the intake because of nonlinear propagation, which must be discriminated from numerical dissipation. This is one of the reasons why an analytical approach is also suggested. It is based on three steps: (i) appraisal of the initial pressure jump of the shock waves; (ii) 2D nonlinear propagation model of Morfey and Fisher; (iii) calculation of the sound power of the 3D ducted acoustic field. In this model, all the blades are assumed to be identical such that only the blade passing frequency and its harmonics are predicted (like in the present numerical simulations). However, transfer from blade passing frequency to multiple pure tones can be evaluated in a fourth step through a statistical analysis of irregularities between blades. Interest of the analytical method is to provide a good estimate of nonlinear acoustic propagation in the upstream duct while being easy and fast to compute. The various methods are applied to two turbofan models, respectively in approach (subsonic) and takeoff (transonic) conditions, and to a Turbomeca turboshaft engine (transonic case). The analytical method in transonic appears to be quite reliable by comparison

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. Donor-impurity-related second and third harmonic generation and optical absorption in GaAs-(Ga,Al)As 3D coupled quantum dot-rings under applied electric field

    NASA Astrophysics Data System (ADS)

    Duque, C. A.; Mora-Ramos, M. E.; Correa, J. D.

    2015-11-01

    The features of some donor-impurity-related nonlinear optical properties in coupled dot-ring nanostructures are investigated with the use of the effective mass and parabolic band approximations. The electron confinement is modeled via a recently reported analytical potential, and the influence of an externally applied static electric field is taken into account. The results show that the increase in the applied field strength causes the blueshift of all the optical responses considered, whereas they can be redshifted or blueshifted depending of the impurity position. For the parameters and interlevel transitions considered in this work, the third harmonic generation is absent when the impurity moves along the same direction of the polarization of the incident resonant radiation.

  16. Minimum Power Requirements and Optimal Rotor Design for Conventional, Compound, and Coaxial Helicopters Using Higher Harmonic Control

    NASA Astrophysics Data System (ADS)

    Giovanetti, Eli B.

    This thesis presents a method for computing the optimal aerodynamic performance of conventional, compound, and coaxial helicopters in trimmed forward flight with a limited set of design variables, including the blade's radial twist and chord distributions and conventional and higher harmonic blade pitch control. The optimal design problem, which is cast as a variational statement, minimizes the sum of the induced and viscous power required to develop a prescribed lift and/or thrust. The variational statement is discretized and solved efficiently using a vortex-lattice technique. We present two variants of the analysis. In the first, the sectional blade aerodynamics are modeled using a linear lift curve and a quadratic drag polar, and flow angles are assumed to be small. The result is a quadratic programming problem that yields a linear set of equations to solve for the unknown optimal design variables. In the second approach, the problem is cast as a constrained nonlinear optimization problem, which is solved using Newton iteration. This approach, which accounts for realistic lift and drag coefficients including the effects of stall and the attendant increase in drag at high angles of attack, is capable of optimizing the blade planform in addition to the radial twist distribution and conventional and higher harmonic blade pitch control. We show that for conventional rotors, coaxial counterrotating rotors, and a wing-rotor compound, using radially varying twist and chord distributions and higher harmonic blade pitch control can produce significant reductions in required power, especially at high advance ratios.

  17. 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.

  18. 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

  19. Correlation of the earth's rotation rate and the secular change of the geomagnetic field. [power spectra/harmonic analysis

    NASA Technical Reports Server (NTRS)

    Jin, R. S.

    1975-01-01

    Power spectral density analysis using Burg's maximum entropy method was applied to the geomagnetic dipole field and its rate of change for the years 1901 to 1969. Both spectra indicate relative maxima at 0.015 cycles/year and its harmonics. These maxima correspond approximately to 66, 33, 22, 17, 13, 11, and 9-year spectral lines. The application of the same analysis techniques to the length-of-day (l.o.d) fluctuations for the period 1865 to 1961 reveal similar spectral characteristics. Although peaks were observed at higher harmonics of the fundamental frequency, the 22-year and 11-year lines are not attributed unambiguously to the solar magnetic cycle and the solar cycle. It is suggested that the similarity in the l.o.d fluctuations and the dipole field variations is related to the motion within the earth's fluid core during the past one hundred years.

  20. Life Cycle GHG Emissions from Conventional Natural Gas Power Generation: Systematic Review and Harmonization (Presentation)

    SciTech Connect

    Heath, G.; O'Donoughue, P.; Whitaker, M.

    2012-12-01

    This research provides a systematic review and harmonization of the life cycle assessment (LCA) literature of electricity generated from conventionally produced natural gas. We focus on estimates of greenhouse gases (GHGs) emitted in the life cycle of electricity generation from conventionally produced natural gas in combustion turbines (NGCT) and combined-cycle (NGCC) systems. A process we term "harmonization" was employed to align several common system performance parameters and assumptions to better allow for cross-study comparisons, with the goal of clarifying central tendency and reducing variability in estimates of life cycle GHG emissions. This presentation summarizes preliminary results.

  1. 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).

  2. 3D weak lensing: Modified theories of gravity

    NASA Astrophysics Data System (ADS)

    Pratten, Geraint; Munshi, Dipak; Valageas, Patrick; Brax, Philippe

    2016-05-01

    Weak lensing (WL) promises to be a particularly sensitive probe of both the growth of large-scale structure as well as the fundamental relation between matter density perturbations and metric perturbations, thus providing a powerful tool with which we may constrain modified theories of gravity (MG) on cosmological scales. Future deep, wide-field WL surveys will provide an unprecedented opportunity to constrain deviations from General Relativity. Employing a 3D analysis based on the spherical Fourier-Bessel expansion, we investigate the extent to which MG theories will be constrained by a typical 3D WL survey configuration including noise from the intrinsic ellipticity distribution σɛ of source galaxies. Here, we focus on two classes of screened theories of gravity: (i) f (R ) chameleon models and (ii) environmentally dependent dilaton models. We use one-loop perturbation theory combined with halo models in order to accurately model the evolution of the matter power spectrum with redshift in these theories. Using a χ2 analysis, we show that for an all-sky spectroscopic survey, the parameter fR0 can be constrained in the range fR0<5 ×10-6(9 ×10-6) for n =1 (2 ) with a 3 σ confidence level. This can be achieved by using relatively low-order angular harmonics ℓ<100 . Higher-order harmonics ℓ>100 could provide tighter constraints but are subject to nonlinear effects, such as baryonic feedback, that must be accounted for. We also employ a Principal Component Analysis in order to study the parameter degeneracies in the MG parameters. The confusion from intrinsic ellipticity correlation and modification of the matter power spectrum at a small scale due to feedback mechanisms is briefly discussed.

  3. 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.

  4. Harmonization of initial estimates of shale gas life cycle greenhouse gas emissions for electric power generation.

    PubMed

    Heath, Garvin A; O'Donoughue, Patrick; Arent, Douglas J; Bazilian, Morgan

    2014-08-05

    Recent technological advances in the recovery of unconventional natural gas, particularly shale gas, have served to dramatically increase domestic production and reserve estimates for the United States and internationally. This trend has led to lowered prices and increased scrutiny on production practices. Questions have been raised as to how greenhouse gas (GHG) emissions from the life cycle of shale gas production and use compares with that of conventionally produced natural gas or other fuel sources such as coal. Recent literature has come to different conclusions on this point, largely due to differing assumptions, comparison baselines, and system boundaries. Through a meta-analytical procedure we call harmonization, we develop robust, analytically consistent, and updated comparisons of estimates of life cycle GHG emissions for electricity produced from shale gas, conventionally produced natural gas, and coal. On a per-unit electrical output basis, harmonization reveals that median estimates of GHG emissions from shale gas-generated electricity are similar to those for conventional natural gas, with both approximately half that of the central tendency of coal. Sensitivity analysis on the harmonized estimates indicates that assumptions regarding liquids unloading and estimated ultimate recovery (EUR) of wells have the greatest influence on life cycle GHG emissions, whereby shale gas life cycle GHG emissions could approach the range of best-performing coal-fired generation under certain scenarios. Despite clarification of published estimates through harmonization, these initial assessments should be confirmed through methane emissions measurements at components and in the atmosphere and through better characterization of EUR and practices.

  5. 3D goes digital: from stereoscopy to modern 3D imaging techniques

    NASA Astrophysics Data System (ADS)

    Kerwien, N.

    2014-11-01

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

  6. High-resolution laser radar: a powerful tool for 3D imaging with potential applications in artwork restoration and medical prosthesis

    NASA Astrophysics Data System (ADS)

    Fantoni, Roberta; Bordone, Andrea; Ferri De Collibus, Mario; Fornetti, Giorgio G.; Guarneri, Marianna; Poggi, Claudio; Ricci, Roberto

    2003-11-01

    A high-resolution laser radar has been developed for laboratory applications at an accurate 3D reconstruction of real objects. The laser scanner can be used to produce single cylindrical range image when the object is placed on a controlled rotating platform or, alternatively, 3 or more linear range images, in order to fully characterize the surface of the object as seen from different points of view. From the sample points, characterized by an uncertainty as small as 100 μm, the complete object surface can be reconstructed by using specifically developed software tools. The system has been successfully applied to scan different types of real surfaces (stone, wood, bones) with relevant applications in industrial machining, artwork classification and medical diagnostics. Significant examples of 3D reconstructions are shown and discussed in view of a specific utilization for reverse engineering applied to artwork restoration and medical prosthesis.

  7. Steady-state and dynamic characteristics of a 20-kHz spacecraft power system - Control of harmonic resonance

    NASA Technical Reports Server (NTRS)

    Wasynczuk, O.; Krause, P. C.; Biess, J. J.; Kapustka, R.

    1990-01-01

    A detailed computer simulation was used to illustrate the steady-state and dynamic operating characteristics of a 20-kHz resonant spacecraft power system. The simulated system consists of a parallel-connected set of DC-inductor resonant inverters (drivers), a 440-V cable, a node transformer, a 220-V cable, and a transformer-rectifier-filter (TRF) AC-to-DC receiver load. Also included in the system are a 1-kW 0.8-pf RL load and a double-LC filter connected at the receiving end of the 20-kHz AC system. The detailed computer simulation was used to illustrate the normal steady-state operating characteristics and the dynamic system performance following, for example, TRF startup. It is shown that without any filtering the given system exhibits harmonic resonances due to an interaction between the switching of the source and/or load converters and the AC system. However, the double-LC filter at the receiving-end of the AC system and harmonic traps connected in series with each of the drivers significantly reduce the harmonic distortion of the 20-kHz bus voltage. Significant additional improvement in the waveform quality can be achieved by including a double-LC filter with each driver.

  8. Optical 3D surface digitizing in forensic medicine: 3D documentation of skin and bone injuries.

    PubMed

    Thali, Michael J; Braun, Marcel; Dirnhofer, Richard

    2003-11-26

    Photography process reduces a three-dimensional (3D) wound to a two-dimensional level. If there is a need for a high-resolution 3D dataset of an object, it needs to be three-dimensionally scanned. No-contact optical 3D digitizing surface scanners can be used as a powerful tool for wound and injury-causing instrument analysis in trauma cases. The 3D skin wound and a bone injury documentation using the optical scanner Advanced TOpometric Sensor (ATOS II, GOM International, Switzerland) will be demonstrated using two illustrative cases. Using this 3D optical digitizing method the wounds (the virtual 3D computer model of the skin and the bone injuries) and the virtual 3D model of the injury-causing tool are graphically documented in 3D in real-life size and shape and can be rotated in the CAD program on the computer screen. In addition, the virtual 3D models of the bone injuries and tool can now be compared in a 3D CAD program against one another in virtual space, to see if there are matching areas. Further steps in forensic medicine will be a full 3D surface documentation of the human body and all the forensic relevant injuries using optical 3D scanners.

  9. Harmonization of initial estimates of shale gas life cycle greenhouse gas emissions for electric power generation

    PubMed Central

    Heath, Garvin A.; O’Donoughue, Patrick; Arent, Douglas J.; Bazilian, Morgan

    2014-01-01

    Recent technological advances in the recovery of unconventional natural gas, particularly shale gas, have served to dramatically increase domestic production and reserve estimates for the United States and internationally. This trend has led to lowered prices and increased scrutiny on production practices. Questions have been raised as to how greenhouse gas (GHG) emissions from the life cycle of shale gas production and use compares with that of conventionally produced natural gas or other fuel sources such as coal. Recent literature has come to different conclusions on this point, largely due to differing assumptions, comparison baselines, and system boundaries. Through a meta-analytical procedure we call harmonization, we develop robust, analytically consistent, and updated comparisons of estimates of life cycle GHG emissions for electricity produced from shale gas, conventionally produced natural gas, and coal. On a per-unit electrical output basis, harmonization reveals that median estimates of GHG emissions from shale gas-generated electricity are similar to those for conventional natural gas, with both approximately half that of the central tendency of coal. Sensitivity analysis on the harmonized estimates indicates that assumptions regarding liquids unloading and estimated ultimate recovery (EUR) of wells have the greatest influence on life cycle GHG emissions, whereby shale gas life cycle GHG emissions could approach the range of best-performing coal-fired generation under certain scenarios. Despite clarification of published estimates through harmonization, these initial assessments should be confirmed through methane emissions measurements at components and in the atmosphere and through better characterization of EUR and practices. PMID:25049378

  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. Simple Harmonic Motion in Harmonic Plane Waves.

    ERIC Educational Resources Information Center

    Benumof, Reuben

    1980-01-01

    Discusses the distribution of kinetic and potential energy in transverse and longitudinal waves and examines the transmission of power and momentum. This discussion is intended to aid in understanding the simple harmonic motion of a particle involved in the propagation of a harmonic mechanical plane wave. (HM)

  14. 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

  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. 3D printing of interdigitated Li-ion microbattery architectures.

    PubMed

    Sun, Ke; Wei, Teng-Sing; Ahn, Bok Yeop; Seo, Jung Yoon; Dillon, Shen J; Lewis, Jennifer A

    2013-09-06

    3D interdigitated microbattery architectures (3D-IMA) are fabricated by printing concentrated lithium oxide-based inks. The microbatteries are composed of interdigitated, high-aspect ratio cathode and anode structures. Our 3D-IMA, which exhibit high areal energy and power densities, may find potential application in autonomously powered microdevices.

  18. Origin of chaos in 3-d Bohmian trajectories

    NASA Astrophysics Data System (ADS)

    Tzemos, Athanasios C.; Contopoulos, George; Efthymiopoulos, Christos

    2016-11-01

    We study the 3-d Bohmian trajectories of a quantum system of three harmonic oscillators. We focus on the mechanism responsible for the generation of chaotic trajectories. We demonstrate the existence of a 3-d analogue of the mechanism found in earlier studies of 2-d systems [1,2], based on moving 2-d 'nodal point-X-point complexes'. In the 3-d case, we observe a foliation of nodal point-X-point complexes, forming a '3-d structure of nodal and X-points'. Chaos is generated when the Bohmian trajectories are scattered at one or more close encounters with such a structure.

  19. The psychology of the 3D experience

    NASA Astrophysics Data System (ADS)

    Janicke, Sophie H.; Ellis, Andrew

    2013-03-01

    With 3D televisions expected to reach 50% home saturation as early as 2016, understanding the psychological mechanisms underlying the user response to 3D technology is critical for content providers, educators and academics. Unfortunately, research examining the effects of 3D technology has not kept pace with the technology's rapid adoption, resulting in large-scale use of a technology about which very little is actually known. Recognizing this need for new research, we conducted a series of studies measuring and comparing many of the variables and processes underlying both 2D and 3D media experiences. In our first study, we found narratives within primetime dramas had the power to shift viewer attitudes in both 2D and 3D settings. However, we found no difference in persuasive power between 2D and 3D content. We contend this lack of effect was the result of poor conversion quality and the unique demands of 3D production. In our second study, we found 3D technology significantly increased enjoyment when viewing sports content, yet offered no added enjoyment when viewing a movie trailer. The enhanced enjoyment of the sports content was shown to be the result of heightened emotional arousal and attention in the 3D condition. We believe the lack of effect found for the movie trailer may be genre-related. In our final study, we found 3D technology significantly enhanced enjoyment of two video games from different genres. The added enjoyment was found to be the result of an increased sense of presence.

  20. 3D ultrafast ultrasound imaging in vivo.

    PubMed

    Provost, Jean; Papadacci, Clement; Arango, Juan Esteban; Imbault, Marion; Fink, Mathias; Gennisson, Jean-Luc; Tanter, Mickael; Pernot, Mathieu

    2014-10-07

    Very high frame rate ultrasound imaging has recently allowed for the extension of the applications of echography to new fields of study such as the functional imaging of the brain, cardiac electrophysiology, and the quantitative imaging of the intrinsic mechanical properties of tumors, to name a few, non-invasively and in real time. In this study, we present the first implementation of Ultrafast Ultrasound Imaging in 3D based on the use of either diverging or plane waves emanating from a sparse virtual array located behind the probe. It achieves high contrast and resolution while maintaining imaging rates of thousands of volumes per second. A customized portable ultrasound system was developed to sample 1024 independent channels and to drive a 32  ×  32 matrix-array probe. Its ability to track in 3D transient phenomena occurring in the millisecond range within a single ultrafast acquisition was demonstrated for 3D Shear-Wave Imaging, 3D Ultrafast Doppler Imaging, and, finally, 3D Ultrafast combined Tissue and Flow Doppler Imaging. The propagation of shear waves was tracked in a phantom and used to characterize its stiffness. 3D Ultrafast Doppler was used to obtain 3D maps of Pulsed Doppler, Color Doppler, and Power Doppler quantities in a single acquisition and revealed, at thousands of volumes per second, the complex 3D flow patterns occurring in the ventricles of the human heart during an entire cardiac cycle, as well as the 3D in vivo interaction of blood flow and wall motion during the pulse wave in the carotid at the bifurcation. This study demonstrates the potential of 3D Ultrafast Ultrasound Imaging for the 3D mapping of stiffness, tissue motion, and flow in humans in vivo and promises new clinical applications of ultrasound with reduced intra--and inter-observer variability.

  1. 3D ultrafast ultrasound imaging in vivo

    NASA Astrophysics Data System (ADS)

    Provost, Jean; Papadacci, Clement; Esteban Arango, Juan; Imbault, Marion; Fink, Mathias; Gennisson, Jean-Luc; Tanter, Mickael; Pernot, Mathieu

    2014-10-01

    Very high frame rate ultrasound imaging has recently allowed for the extension of the applications of echography to new fields of study such as the functional imaging of the brain, cardiac electrophysiology, and the quantitative imaging of the intrinsic mechanical properties of tumors, to name a few, non-invasively and in real time. In this study, we present the first implementation of Ultrafast Ultrasound Imaging in 3D based on the use of either diverging or plane waves emanating from a sparse virtual array located behind the probe. It achieves high contrast and resolution while maintaining imaging rates of thousands of volumes per second. A customized portable ultrasound system was developed to sample 1024 independent channels and to drive a 32  ×  32 matrix-array probe. Its ability to track in 3D transient phenomena occurring in the millisecond range within a single ultrafast acquisition was demonstrated for 3D Shear-Wave Imaging, 3D Ultrafast Doppler Imaging, and, finally, 3D Ultrafast combined Tissue and Flow Doppler Imaging. The propagation of shear waves was tracked in a phantom and used to characterize its stiffness. 3D Ultrafast Doppler was used to obtain 3D maps of Pulsed Doppler, Color Doppler, and Power Doppler quantities in a single acquisition and revealed, at thousands of volumes per second, the complex 3D flow patterns occurring in the ventricles of the human heart during an entire cardiac cycle, as well as the 3D in vivo interaction of blood flow and wall motion during the pulse wave in the carotid at the bifurcation. This study demonstrates the potential of 3D Ultrafast Ultrasound Imaging for the 3D mapping of stiffness, tissue motion, and flow in humans in vivo and promises new clinical applications of ultrasound with reduced intra—and inter-observer variability.

  2. Observations of power line harmonic radiation by the low-altitude AUREOL 3 satellite

    SciTech Connect

    Parrot, M.

    1994-03-01

    This paper presents observations of very low frequency radiation in the lower part of the ionosphere from a polar orbiting satellite at low latitudes. It was able to record several observation of low frequency radiation which is very close to a harmonic of the 50 Hz line frequency. The frequency is observed to drift in time, from 1 to 8 Hz/sec. They are not sure how to account for this apparent non-linear coupling of these very low frequency waves into the ionosphere.

  3. An Improved Version of TOPAZ 3D

    SciTech Connect

    Krasnykh, Anatoly

    2003-07-29

    An improved version of the TOPAZ 3D gun code is presented as a powerful tool for beam optics simulation. In contrast to the previous version of TOPAZ 3D, the geometry of the device under test is introduced into TOPAZ 3D directly from a CAD program, such as Solid Edge or AutoCAD. In order to have this new feature, an interface was developed, using the GiD software package as a meshing code. The article describes this method with two models to illustrate the results.

  4. Magnetic fields dispersed by high-voltage power lines: an advanced evaluation method based on 3-D models of electrical lines and the territory.

    PubMed

    Andreuccetti, D; Zoppetti, N

    2004-01-01

    An advanced numerical evaluation tool is proposed for calculating the magnetic flux density dispersed by high-voltage power lines. When compared to existing software packages based on the application of standardized methods, this tool turned out to be particularly suitable for making accurate evaluations on vast portions of the territory, especially when the contribution of numerous aerial and/or underground lines must be taken into account. The aspects of the tool of greatest interest are (1) the interaction with an electronic archive of power lines, from which all the information necessary for the calculation is obtained; (2) the use of three-dimensional models of both the power lines and the territory crossed by these; (3) the direct interfacing with electronic cartography; and finally (4) the use of a representation procedure for the results that is based on contour maps. The tool had proven to be very useful especially for Environmental Impact Assessment procedures relative to new power lines.

  5. 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.

  6. '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.

  7. 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

  8. MOM3D/EM-ANIMATE - MOM3D WITH ANIMATION CODE

    NASA Technical Reports Server (NTRS)

    Shaeffer, J. F.

    1994-01-01

    compare surface-current distribution due to various initial excitation directions or electric field orientations. The program can accept up to 50 planes of field data consisting of a grid of 100 by 100 field points. These planes of data are user selectable and can be viewed individually or concurrently. With these preset limits, the program requires 55 megabytes of core memory to run. These limits can be changed in the header files to accommodate the available core memory of an individual workstation. An estimate of memory required can be made as follows: approximate memory in bytes equals (number of nodes times number of surfaces times 14 variables times bytes per word, typically 4 bytes per floating point) plus (number of field planes times number of nodes per plane times 21 variables times bytes per word). This gives the approximate memory size required to store the field and surface-current data. The total memory size is approximately 400,000 bytes plus the data memory size. The animation calculations are performed in real time at any user set time step. For Silicon Graphics Workstations that have multiple processors, this program has been optimized to perform these calculations on multiple processors to increase animation rates. The optimized program uses the SGI PFA (Power FORTRAN Accelerator) library. On single processor machines, the parallelization directives are seen as comments to the program and will have no effect on compilation or execution. MOM3D and EM-ANIMATE are written in FORTRAN 77 for interactive or batch execution on SGI series computers running IRIX 3.0 or later. The RAM requirements for these programs vary with the size of the problem being solved. A minimum of 30Mb of RAM is required for execution of EM-ANIMATE; however, the code may be modified to accommodate the available memory of an individual workstation. For EM-ANIMATE, twenty-four bit, double-buffered color capability is suggested, but not required. Sample executables and sample input and

  9. 3D Ultrafast Ultrasound Imaging In Vivo

    PubMed Central

    Provost, Jean; Papadacci, Clement; Arango, Juan Esteban; Imbault, Marion; Gennisson, Jean-Luc; Tanter, Mickael; Pernot, Mathieu

    2014-01-01

    Very high frame rate ultrasound imaging has recently allowed for the extension of the applications of echography to new fields of study such as the functional imaging of the brain, cardiac electrophysiology, and the quantitative real-time imaging of the intrinsic mechanical properties of tumors, to name a few, non-invasively and in real time. In this study, we present the first implementation of Ultrafast Ultrasound Imaging in three dimensions based on the use of either diverging or plane waves emanating from a sparse virtual array located behind the probe. It achieves high contrast and resolution while maintaining imaging rates of thousands of volumes per second. A customized portable ultrasound system was developed to sample 1024 independent channels and to drive a 32×32 matrix-array probe. Its capability to track in 3D transient phenomena occurring in the millisecond range within a single ultrafast acquisition was demonstrated for 3-D Shear-Wave Imaging, 3-D Ultrafast Doppler Imaging and finally 3D Ultrafast combined Tissue and Flow Doppler. The propagation of shear waves was tracked in a phantom and used to characterize its stiffness. 3-D Ultrafast Doppler was used to obtain 3-D maps of Pulsed Doppler, Color Doppler, and Power Doppler quantities in a single acquisition and revealed, for the first time, the complex 3-D flow patterns occurring in the ventricles of the human heart during an entire cardiac cycle, and the 3-D in vivo interaction of blood flow and wall motion during the pulse wave in the carotid at the bifurcation. This study demonstrates the potential of 3-D Ultrafast Ultrasound Imaging for the 3-D real-time mapping of stiffness, tissue motion, and flow in humans in vivo and promises new clinical applications of ultrasound with reduced intra- and inter-observer variability. PMID:25207828

  10. Comparison of NSTX FIDA, Charge Exchange, and Neutron Fluxes with Calculated Signals Based on CQL3D-FOW Distribution Functions

    NASA Astrophysics Data System (ADS)

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

    2014-10-01

    Ion distribution function calculations with CQL3D have been substantially advanced through implementation of guiding-center-orbit-based Fokker-Planck Coefficients. The resulting finite-orbit-width (FOW) calculations are carried out with a fast CQL3D-Hybrid-FOW option, and in a slower but neoclassically complete (except no Er yet) CQL3D-FOW option. Good comparison between time-dependent Fast Ion Diagnostic FIDA, NPA, and neutron signals resulting from neutral beaminjection(NBI) and high harmonic fast wave (HHFW) power injected into the NSTX spherical tokamak have been simulated with the CQL3D-Hybrid-FOW, using only the FOW effects on QL diffusion, and particle losses, direct and CX. Comparisons are also made with recent CQL3D-FOW results, as well as between the original FIDA calculation code and a recent fortran version. Supported by USDOE Grants SC0006614, ER54744, and ER44649.

  11. 3-D transient analysis of pebble-bed HTGR by TORT-TD/ATTICA3D

    SciTech Connect

    Seubert, A.; Sureda, A.; Lapins, J.; Buck, M.; Bader, J.; Laurien, E.

    2012-07-01

    As most of the acceptance criteria are local core parameters, application of transient 3-D fine mesh neutron transport and thermal hydraulics coupled codes is mandatory for best estimate evaluations of safety margins. This also applies to high-temperature gas cooled reactors (HTGR). Application of 3-D fine-mesh transient transport codes using few energy groups coupled with 3-D thermal hydraulics codes becomes feasible in view of increasing computing power. This paper describes the discrete ordinates based coupled code system TORT-TD/ATTICA3D that has recently been extended by a fine-mesh diffusion solver. Based on transient analyses for the PBMR-400 design, the transport/diffusion capabilities are demonstrated and 3-D local flux and power redistribution effects during a partial control rod withdrawal are shown. (authors)

  12. 3-D Color Wheels

    ERIC Educational Resources Information Center

    DuBois, Ann

    2010-01-01

    The blending of information from an academic class with projects from art class can do nothing but strengthen the learning power of the student. Creating three-dimensional color wheels provides the perfect opportunity to combine basic geometry knowledge with color theory. In this article, the author describes how her seventh-grade painting…

  13. Optically rewritable 3D liquid crystal displays.

    PubMed

    Sun, J; Srivastava, A K; Zhang, W; Wang, L; Chigrinov, V G; Kwok, H S

    2014-11-01

    Optically rewritable liquid crystal display (ORWLCD) is a concept based on the optically addressed bi-stable display that does not need any power to hold the image after being uploaded. Recently, the demand for the 3D image display has increased enormously. Several attempts have been made to achieve 3D image on the ORWLCD, but all of them involve high complexity for image processing on both hardware and software levels. In this Letter, we disclose a concept for the 3D-ORWLCD by dividing the given image in three parts with different optic axis. A quarter-wave plate is placed on the top of the ORWLCD to modify the emerging light from different domains of the image in different manner. Thereafter, Polaroid glasses can be used to visualize the 3D image. The 3D image can be refreshed, on the 3D-ORWLCD, in one-step with proper ORWLCD printer and image processing, and therefore, with easy image refreshing and good image quality, such displays can be applied for many applications viz. 3D bi-stable display, security elements, etc.

  14. Fetal ECG Extraction from Abdominal Signals: A Review on Suppression of Fundamental Power Line Interference Component and Its Harmonics

    PubMed Central

    Ţarălungă, Dragoş-Daniel; Ungureanu, Georgeta-Mihaela; Gussi, Ilinca; Strungaru, Rodica; Wolf, Werner

    2014-01-01

    Interference of power line (PLI) (fundamental frequency and its harmonics) is usually present in biopotential measurements. Despite all countermeasures, the PLI still corrupts physiological signals, for example, electromyograms (EMG), electroencephalograms (EEG), and electrocardiograms (ECG). When analyzing the fetal ECG (fECG) recorded on the maternal abdomen, the PLI represents a particular strong noise component, being sometimes 10 times greater than the fECG signal, and thus impairing the extraction of any useful information regarding the fetal health state. Many signal processing methods for cancelling the PLI from biopotentials are available in the literature. In this review study, six different principles are analyzed and discussed, and their performance is evaluated on simulated data (three different scenarios), based on five quantitative performance indices. PMID:24660020

  15. Artificial Neural Networks as a powerful numerical tool to classify specific features of a tooth based on 3D scan data.

    PubMed

    Raith, Stefan; Vogel, Eric Per; Anees, Naeema; Keul, Christine; Güth, Jan-Frederik; Edelhoff, Daniel; Fischer, Horst

    2017-01-01

    Chairside manufacturing based on digital image acquisition is gainingincreasing importance in dentistry. For the standardized application of these methods, it is paramount to have highly automated digital workflows that can process acquired 3D image data of dental surfaces. Artificial Neural Networks (ANNs) arenumerical methods primarily used to mimic the complex networks of neural connections in the natural brain. Our hypothesis is that an ANNcan be developed that is capable of classifying dental cusps with sufficient accuracy. This bears enormous potential for an application in chairside manufacturing workflows in the dental field, as it closes the gap between digital acquisition of dental geometries and modern computer-aided manufacturing techniques.Three-dimensional surface scans of dental casts representing natural full dental arches were transformed to range image data. These data were processed using an automated algorithm to detect candidates for tooth cusps according to salient geometrical features. These candidates were classified following common dental terminology and used as training data for a tailored ANN.For the actual cusp feature description, two different approaches were developed and applied to the available data: The first uses the relative location of the detected cusps as input data and the second method directly takes the image information given in the range images. In addition, a combination of both was implemented and investigated.Both approaches showed high performance with correct classifications of 93.3% and 93.5%, respectively, with improvements by the combination shown to be minor.This article presents for the first time a fully automated method for the classification of teeththat could be confirmed to work with sufficient precision to exhibit the potential for its use in clinical practice,which is a prerequisite for automated computer-aided planning of prosthetic treatments with subsequent automated chairside manufacturing.

  16. Large power factor and anomalous Hall effect and their correlation with observed linear magneto resistance in Co-doped Bi2Se3 3D topological insulator.

    PubMed

    Singh, Rahul; Shukla, K K; Kumar, A; Okram, G S; Singh, D; Ganeshan, V; Lakhani, Archana; Ghosh, A K; Chatterjee, Sandip

    2016-09-21

    Magnetoresistance (MR), thermo power, magnetization and Hall effect measurements have been performed on Co-doped Bi2Se3 topological insulators. The undoped sample shows that the maximum MR as a destructive interference due to a π-Berry phase leads to a decrease of MR. As the Co is doped, the linearity in MR is increased. The observed MR of Bi2Se3 can be explained with the classical model. The low temperature MR behavior of Co doped samples cannot be explained with the same model, but can be explained with the quantum linear MR model. Magnetization behavior indicates the establishment of ferromagnetic ordering with Co doping. Hall effect data also supports the establishment of ferromagnetic ordering in Co-doped Bi2Se3 samples by showing the anomalous Hall effect. Furthermore, when spectral weight suppression is insignificant, Bi2Se3 behaves as a dilute magnetic semiconductor. Moreover, the maximum power factor is observed when time reversal symmetry (TRS) is maintained. As the TRS is broken the power factor value is decreased, which indicates that with the rise of Dirac cone above the Fermi level the anomalous Hall effect and linearity in MR increase and the power factor decreases.

  17. Analysis of Harmonic Distortion in an Integrated Power System for Naval Applications

    DTIC Science & Technology

    2005-06-01

    circuit breaker with the highest current handling capabilities are 5000 amps steady state and 63kA fault. These ratings limit the power handling...reactance, and power capability. Figure 7-2 shows the fault current expected for subtransient reactances of 15%, 20%, and 25%. At 15%, the 63kA breaker

  18. High-Efficiency Robust Free-Standing Composited Phosphor Films with 2D and 3D Nanostructures for High-Power Remote White LEDs.

    PubMed

    Lai, Chun-Feng; Li, Jia-Sian; Shen, Chung-Wen

    2017-02-08

    This study demonstrated that combined free-standing quasi-amorphous/micropattern (QA/MP) composited resin film-assisted phosphor films enhanced the mechanical robustness, luminous efficacy, color rendering index (CRI), and special R9 of high-power remote warm white light-emitting diodes (WLEDs). Introducing QA/MP nanostructures into phosphor film resulted in high efficiency of remote warm WLEDs with low phosphor thickness (approximately 25 μm) and reduced the correlated color temperature (CCT) from cold white light (approximately 5565 K) to warm white light (approximately 3178 K). The QA/MP composited phosphor films (CPFs) used for high-power remote WLEDs enhanced the CRI and special R9 and reduced the CCT. These results were attributed to that QA resin film reflected the blue light and re-emitted the added red emission. CIR (84), a natural warm white CCT (3178 K), and an acceptable luminous efficacy (102.5 lm/W) were achieved from the QA/MP CPFs of high-power remote WLEDs during operation at an input power of 10 W (current of 700 mA). The bending strength of QA/MP CPFs at approximately 112 N was significantly enhanced by 40% compared with that of flat CPFs. The QA/MP CPFs applied to high-power remote WLEDs exhibited good thermal and optical stability. QA/MP CPFs were also conducted to a reliability analysis (RA), in which temperature of 85 °C and relative humidity of 85% were applied for 3288 h. Lumen maintenance was degraded by 8% during RA test because the transmittance of trimethylolopropane ethoxylate triacrylate resins was degraded under high temperature. Overall, we implemented a reliable and inexpensive technology that can potentially reduce phosphor thickness, address the out-bin problems of defective WLEDs, and fabricate flat-panel lighting source with good lighting quality.

  19. MOM3D/EM-ANIMATE - MOM3D WITH ANIMATION CODE

    NASA Technical Reports Server (NTRS)

    Shaeffer, J. F.

    1994-01-01

    MOM3D (LAR-15074) is a FORTRAN method-of-moments electromagnetic analysis algorithm for open or closed 3-D perfectly conducting or resistive surfaces. Radar cross section with plane wave illumination is the prime analysis emphasis; however, provision is also included for local port excitation for computing antenna gain patterns and input impedances. The Electric Field Integral Equation form of Maxwell's equations is solved using local triangle couple basis and testing functions with a resultant system impedance matrix. The analysis emphasis is not only for routine RCS pattern predictions, but also for phenomenological diagnostics: bistatic imaging, currents, and near scattered/total electric fields. The images, currents, and near fields are output in form suitable for animation. MOM3D computes the full backscatter and bistatic radar cross section polarization scattering matrix (amplitude and phase), body currents and near scattered and total fields for plane wave illumination. MOM3D also incorporates a new bistatic k space imaging algorithm for computing down range and down/cross range diagnostic images using only one matrix inversion. MOM3D has been made memory and cpu time efficient by using symmetric matrices, symmetric geometry, and partitioned fixed and variable geometries suitable for design iteration studies. MOM3D may be run interactively or in batch mode on 486 IBM PCs and compatibles, UNIX workstations or larger computers. A 486 PC with 16 megabytes of memory has the potential to solve a 30 square wavelength (containing 3000 unknowns) symmetric configuration. Geometries are described using a triangular mesh input in the form of a list of spatial vertex points and a triangle join connection list. The EM-ANIMATE (LAR-15075) program is a specialized visualization program that displays and animates the near-field and surface-current solutions obtained from an electromagnetics program, in particular, that from MOM3D. The EM-ANIMATE program is windows based and

  20. The role of tissue harmonic imaging ultrasound combined with power Doppler ultrasound in the diagnosis of childhood febrile urinary tract infections

    PubMed Central

    İlarslan, Nisa Eda Çullas; Fitöz, Ömer Suat; Öztuna, Derya Gökmen; Küçük, Nuriye Özlem; Yalçınkaya, Fatma Fatoş

    2015-01-01

    Aim: This study assessed the ability of tissue harmonic imaging ultrasound combined with power Doppler ultrasound in the detection of childhood febrile urinary tract infections in comparison with the gold standard reference method: Tc-99m dimercaptosuccinicacid renal cortical scintigraphy. Material and Methods: This prospective study included 60 patients who were hospitalized with a first episode of febrile urinary tract infections. All children were examined with dimercaptosuccinicacid scan and tissue harmonic imaging ultrasound combined with power Doppler ultrasound within the first 3 days of admission. Results: Signs indicative of acute infection were observed in 29 patients according to the results of tissue harmonic imaging ultrasound combined with power Doppler ultrasound while dimercaptosuccinicacid scan revealed abnormal findings in 33 patients. The sensitivity, specificity, positive predictive value and negative predictive value of tissue harmonic imaging combined with power Doppler ultrasound using dimercaptosuccinicacid scintigraphy as the reference method in patients diagnosed with first episode febrile urinary tract infections were calculated as 57.58% (95% confidence interval: 40.81%–72.76%); 62.96% (95% confidence interval: 44.23%–78.47%); 65.52% (95% confidence interval: 52.04%–77%); 54.84% (95% confidence interval: 41.54%–67.52%); respectively. Conclusions: Although current results exhibit inadequate success of power Doppler ultrasound, this practical and radiation-free method may soon be comprise a part of the routine ultrasonographic evaluation of febrile urinary tract infections of childhood if patients are evaluated early and under appropriate sedation. PMID:26265892

  1. 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.

  2. Harmonic analysis of electrical distribution systems

    SciTech Connect

    1996-03-01

    This report presents data pertaining to research on harmonics of electric power distribution systems. Harmonic data is presented on RMS and average measurements for determination of harmonics in buildings; fluorescent ballast; variable frequency drive; georator geosine harmonic data; uninterruptible power supply; delta-wye transformer; westinghouse suresine; liebert datawave; and active injection mode filter data.

  3. Effectiveness of evaluating tumor vascularization using 3D power Doppler ultrasound with high-definition flow technology in the prediction of the response to neoadjuvant chemotherapy for T2 breast cancer: a preliminary report

    NASA Astrophysics Data System (ADS)

    Shia, Wei-Chung; Chen, Dar-Ren; Huang, Yu-Len; Wu, Hwa-Koon; Kuo, Shou-Jen

    2015-10-01

    The aim of this study was to evaluate the effectiveness of advanced ultrasound (US) imaging of vascular flow and morphological features in the prediction of a pathologic complete response (pCR) and a partial response (PR) to neoadjuvant chemotherapy for T2 breast cancer. Twenty-nine consecutive patients with T2 breast cancer treated with six courses of anthracycline-based neoadjuvant chemotherapy were enrolled. Three-dimensional (3D) power Doppler US with high-definition flow (HDF) technology was used to investigate the blood flow in and morphological features of the tumors. Six vascularity quantization features, three morphological features, and two vascular direction features were selected and extracted from the US images. A support vector machine was used to evaluate the changes in vascularity after neoadjuvant chemotherapy, and pCR and PR were predicted on the basis of these changes. The most accurate prediction of pCR was achieved after the first chemotherapy cycle, with an accuracy of 93.1% and a specificity of 85.5%, while that of a PR was achieved after the second cycle, with an accuracy of 79.31% and a specificity of 72.22%. Vascularity data can be useful to predict the effects of neoadjuvant chemotherapy. Determination of changes in vascularity after neoadjuvant chemotherapy using 3D power Doppler US with HDF can generate accurate predictions of the patient response, facilitating early decision-making.

  4. 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.

  5. 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

  6. 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.  

  7. Spherical harmonic analysis of the PSCz galaxy catalogue: redshift distortions and the real-space power spectrum

    NASA Astrophysics Data System (ADS)

    Tadros, H.; Ballinger, W. E.; Taylor, A. N.; Heavens, A. F.; Efstathiou, G.; Saunders, W.; Frenk, C. S.; Keeble, O.; McMahon, R.; Maddox, S. J.; Oliver, S.; Rowan-Robinson, M.; Sutherland, W. J.; White, S. D. M.

    1999-05-01

    We apply the formalism of spherical harmonic decomposition to the galaxy density field of the IRAS PSCz redshift survey. The PSCz redshift survey has almost all-sky coverage and includes IRAS galaxies to a flux limit of 0.6 Jy. Using maximum likelihood methods to examine (to first order) the distortion of the galaxy pattern resulting from redshift coordinates, we have measured the parameter beta=Omega^{0.6}/b. We also simultaneously measure either (a) the undistorted amplitude of perturbations in the galaxy distribution when a parametrized power spectrum is assumed, or (b) the shape and amplitude of the real-space power spectrum if the band-power in a set of passbands is measured in a step-wise fashion. These methods are extensively tested on a series of CDM, Lambda CDM and MDM simulations and are found to be unbiased. We obtain consistent results for the subset of the PSCz catalogue with flux above 0.75 Jy, but inclusion of galaxies to the formal flux limit of the catalogue gives variations which are larger than our internal errors. For the 0.75-Jy catalogue we find, in the case of a parametrized power spectrum, beta=0.58+/-0.26 and the amplitude of the real-space power measured at wavenumber k=0.1h Mpc^-1 is Delta_0.1=0.42+/-0.03. Freeing the shape of the power spectrum we find that beta=0.47+/-0.16 (conditional error) and Delta_0.1=0.47+/-0.03. The shape of the real-space power spectrum is consistent with a Gamma=0.2 CDM-like model, but does not strongly rule out a number of other models. Finally by combining our estimate of the amplitude of galaxy clustering and the distortion parameter we find the amplitude of mass fluctuations on a scale k=0.1h Mpc^-1 is Delta_rho=0.24Omega_0^-0.6, with an uncertainty of 50 per cent.

  8. Delft3D turbine turbulence module

    SciTech Connect

    Chartrand, Chris; Jagers, Bert

    2016-04-18

    The DOE has funded Sandia National Labs (SNL) to develop an open-source modeling tool to guide the design and layout of marine hydrokinetic (MHK) arrays to maximize power production while minimizing environmental effects. This modeling framework simulates flows through and around a MHK arrays while quantifying environmental responses. As an augmented version of the Dutch company, Deltares’s, environmental hydrodynamics code, Delft3D, SNL-Delft3D includes a new module that simulates energy conversion (momentum withdrawal) by MHK devices with commensurate changes in the turbulent kinetic energy and its dissipation rate.

  9. 3D Modeling Engine Representation Summary Report

    SciTech Connect

    Steven Prescott; Ramprasad Sampath; Curtis Smith; Timothy Yang

    2014-09-01

    Computers have been used for 3D modeling and simulation, but only recently have computational resources been able to give realistic results in a reasonable time frame for large complex models. This summary report addressed the methods, techniques, and resources used to develop a 3D modeling engine to represent risk analysis simulation for advanced small modular reactor structures and components. The simulations done for this evaluation were focused on external events, specifically tsunami floods, for a hypothetical nuclear power facility on a coastline.

  10. 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.

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. A Novel Ku-Band/Ka-Band and Ka-Band/E-Band Multimode Waveguide Couplers for Power Measurement of Traveling-Wave Tube Amplifier Harmonic Frequencies

    NASA Technical Reports Server (NTRS)

    Wintucky, Edwin G.; Simons, Rainee N.

    2015-01-01

    This paper presents the design, fabrication and test results for a novel waveguide multimode directional coupler (MDC). The coupler, fabricated from two dissimilar frequency band waveguides, is capable of isolating power at the second harmonic frequency from the fundamental power at the output port of a traveling-wave tube (TWT) amplifier. Test results from proof-of-concept demonstrations are presented for a Ku-band/Ka-band MDC and a Ka-band/E-band MDC. In addition to power measurements at harmonic frequencies, a potential application of the MDC is in the design of a satellite borne beacon source for atmospheric propagation studies at millimeter-wave (mm-wave) frequencies (Ka-band and E-band).

  16. 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

  17. 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.

  18. 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.

  19. 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.

  20. Multi-view and 3D deformable part models.

    PubMed

    Pepik, Bojan; Stark, Michael; Gehler, Peter; Schiele, Bernt

    2015-11-01

    As objects are inherently 3D, they have been modeled in 3D in the early days of computer vision. Due to the ambiguities arising from mapping 2D features to 3D models, 3D object representations have been neglected and 2D feature-based models are the predominant paradigm in object detection nowadays. While such models have achieved outstanding bounding box detection performance, they come with limited expressiveness, as they are clearly limited in their capability of reasoning about 3D shape or viewpoints. In this work, we bring the worlds of 3D and 2D object representations closer, by building an object detector which leverages the expressive power of 3D object representations while at the same time can be robustly matched to image evidence. To that end, we gradually extend the successful deformable part model [1] to include viewpoint information and part-level 3D geometry information, resulting in several different models with different level of expressiveness. We end up with a 3D object model, consisting of multiple object parts represented in 3D and a continuous appearance model. We experimentally verify that our models, while providing richer object hypotheses than the 2D object models, provide consistently better joint object localization and viewpoint estimation than the state-of-the-art multi-view and 3D object detectors on various benchmarks (KITTI [2] , 3D object classes [3] , Pascal3D+ [4] , Pascal VOC 2007 [5] , EPFL multi-view cars[6] ).

  1. 3D Simulation: Microgravity Environments and Applications

    NASA Technical Reports Server (NTRS)

    Hunter, Steve L.; Dischinger, Charles; Estes, Samantha; Parker, Nelson C. (Technical Monitor)

    2001-01-01

    Most, if not all, 3-D and Virtual Reality (VR) software programs are designed for one-G gravity applications. Space environments simulations require gravity effects of one one-thousandth to one one-million of that of the Earth's surface (10(exp -3) - 10(exp -6) G), thus one must be able to generate simulations that replicate those microgravity effects upon simulated astronauts. Unfortunately, the software programs utilized by the National Aeronautical and Space Administration does not have the ability to readily neutralize the one-G gravity effect. This pre-programmed situation causes the engineer or analysis difficulty during micro-gravity simulations. Therefore, microgravity simulations require special techniques or additional code in order to apply the power of 3D graphic simulation to space related applications. This paper discusses the problem and possible solutions to allow microgravity 3-D/VR simulations to be completed successfully without program code modifications.

  2. Impedance mammograph 3D phantom studies.

    PubMed

    Wtorek, J; Stelter, J; Nowakowski, A

    1999-04-20

    The results obtained using the Technical University of Gdansk Electroimpedance Mammograph (TUGEM) of a 3D phantom study are presented. The TUGEM system is briefly described. The hardware contains the measurement head and DSP-based identification modules controlled by a PC computer. A specially developed reconstruction algorithm, Regulated Correction Frequency Algebraic Reconstruction Technique (RCFART), is used to obtain 3D images. To visualize results, the Advance Visualization System (AVS) is used. It allows a powerful image processing on a fast workstation or on a high-performance computer. Results of three types of 3D conductivity perturbations used in the study (aluminum, Plexiglas, and cucumber) are shown. The relative volumes of perturbations less than 2% of the measurement chamber are easily evidenced.

  3. 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

  4. 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

  5. Design of a high-power, high-gain, 2nd harmonic, 22.848 GHz gyroklystron

    SciTech Connect

    Veale, M.; Purohit, P.; Lawson, W.

    2013-08-15

    In this paper we consider the design of a four-cavity, high-gain K-band gyroklystron experiment for high gradient structure testing. The frequency doubling gyroklystron utilizes a beam voltage of 500 kV and a beam current of 200 A from a magnetron injection gun (MIG) originally designed for a lower-frequency device. The microwave circuit features input and gain cavities in the circular TE{sub 011} mode and penultimate and output cavities that operate at the second harmonic in the TE{sub 021} mode. We investigate the MIG performance and study the behavior of the circuit for different values of perpendicular to parallel velocity ratio (α= V{sub ⊥}/ V{sub z}). This microwave tube is expected to be able to produce at least 20 MW of power in 1μs pulses at a repetition rate of at least 120 Hz. A maximum efficiency of 26% and a large signal gain of 58 dB under zero-drive stable conditions were simulated for a velocity ratio equal to 1.35.

  6. 3D Integration for Wireless Multimedia

    NASA Astrophysics Data System (ADS)

    Kimmich, Georg

    The convergence of mobile phone, internet, mapping, gaming and office automation tools with high quality video and still imaging capture capability is becoming a strong market trend for portable devices. High-density video encode and decode, 3D graphics for gaming, increased application-software complexity and ultra-high-bandwidth 4G modem technologies are driving the CPU performance and memory bandwidth requirements close to the PC segment. These portable multimedia devices are battery operated, which requires the deployment of new low-power-optimized silicon process technologies and ultra-low-power design techniques at system, architecture and device level. Mobile devices also need to comply with stringent silicon-area and package-volume constraints. As for all consumer devices, low production cost and fast time-to-volume production is key for success. This chapter shows how 3D architectures can bring a possible breakthrough to meet the conflicting power, performance and area constraints. Multiple 3D die-stacking partitioning strategies are described and analyzed on their potential to improve the overall system power, performance and cost for specific application scenarios. Requirements and maturity of the basic process-technology bricks including through-silicon via (TSV) and die-to-die attachment techniques are reviewed. Finally, we highlight new challenges which will arise with 3D stacking and an outlook on how they may be addressed: Higher power density will require thermal design considerations, new EDA tools will need to be developed to cope with the integration of heterogeneous technologies and to guarantee signal and power integrity across the die stack. The silicon/wafer test strategies have to be adapted to handle high-density IO arrays, ultra-thin wafers and provide built-in self-test of attached memories. New standards and business models have to be developed to allow cost-efficient assembly and testing of devices from different silicon and technology

  7. Classification and 3D averaging with missing wedge correction in biological electron tomography ☆

    PubMed Central

    Bartesaghi, A.; Sprechmann, P.; Liu, J.; Randall, G.; Sapiro, G.; Subramaniam, S.

    2008-01-01

    Strategies for the determination of 3D structures of biological macromolecules using electron crystallography and single-particle electron microscopy utilize powerful tools for the averaging of information obtained from 2D projection images of structurally homogeneous specimens. In contrast, electron tomographic approaches have often been used to study the 3D structures of heterogeneous, one-of-a-kind objects such as whole cells where image-averaging strategies are not applicable. Complex entities such as cells and viruses, nevertheless, contain multiple copies of numerous macromolecules that can individually be subjected to 3D averaging. Here we present a complete framework for alignment, classification, and averaging of volumes derived by electron tomography that is computationally efficient and effectively accounts for the missing wedge that is inherent to limited-angle electron tomography. Modeling the missing data as a multiplying mask in reciprocal space we show that the effect of the missing wedge can be accounted for seamlessly in all alignment and classification operations. We solve the alignment problem using the convolution theorem in harmonic analysis, thus eliminating the need for approaches that require exhaustive angular search, and adopt an iterative approach to alignment and classification that does not require the use of external references. We demonstrate that our method can be successfully applied for 3D classification and averaging of phantom volumes as well as experimentally obtained tomograms of GroEL where the outcomes of the analysis can be quantitatively compared against the expected results. PMID:18440828

  8. Scalable Multi-Platform Distribution of Spatial 3d Contents

    NASA Astrophysics Data System (ADS)

    Klimke, J.; Hagedorn, B.; Döllner, J.

    2013-09-01

    Virtual 3D city models provide powerful user interfaces for communication of 2D and 3D geoinformation. Providing high quality visualization of massive 3D geoinformation in a scalable, fast, and cost efficient manner is still a challenging task. Especially for mobile and web-based system environments, software and hardware configurations of target systems differ significantly. This makes it hard to provide fast, visually appealing renderings of 3D data throughout a variety of platforms and devices. Current mobile or web-based solutions for 3D visualization usually require raw 3D scene data such as triangle meshes together with textures delivered from server to client, what makes them strongly limited in terms of size and complexity of the models they can handle. In this paper, we introduce a new approach for provisioning of massive, virtual 3D city models on different platforms namely web browsers, smartphones or tablets, by means of an interactive map assembled from artificial oblique image tiles. The key concept is to synthesize such images of a virtual 3D city model by a 3D rendering service in a preprocessing step. This service encapsulates model handling and 3D rendering techniques for high quality visualization of massive 3D models. By generating image tiles using this service, the 3D rendering process is shifted from the client side, which provides major advantages: (a) The complexity of the 3D city model data is decoupled from data transfer complexity (b) the implementation of client applications is simplified significantly as 3D rendering is encapsulated on server side (c) 3D city models can be easily deployed for and used by a large number of concurrent users, leading to a high degree of scalability of the overall approach. All core 3D rendering techniques are performed on a dedicated 3D rendering server, and thin-client applications can be compactly implemented for various devices and platforms.

  9. Harmonic Nanoparticles for Regenerative Research

    PubMed Central

    Ronzoni, Flavio; Magouroux, Thibaud; Vernet, Remi; Extermann, Jérôme; Crotty, Darragh; Prina-Mello, Adriele; Ciepielewski, Daniel; Volkov, Yuri; Bonacina, Luigi; Wolf, Jean-Pierre; Jaconi, Marisa

    2014-01-01

    In this visualized experiment, protocol details are provided for in vitro labeling of human embryonic stem cells (hESC) with second harmonic generation nanoparticles (HNPs). The latter are a new family of probes recently introduced for labeling biological samples for multi-photon imaging. HNPs are capable of doubling the frequency of excitation light by the nonlinear optical process of second harmonic generation with no restriction on the excitation wavelength. Multi-photon based methodologies for hESC differentiation into cardiac clusters (maintained as long term air-liquid cultures) are presented in detail. In particular, evidence on how to maximize the intense second harmonic (SH) emission of isolated HNPs during 3D monitoring of beating cardiac tissue in 3D is shown. The analysis of the resulting images to retrieve 3D displacement patterns is also detailed. PMID:24836220

  10. 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.

  11. Simple proposal for radial 3D needlets

    NASA Astrophysics Data System (ADS)

    Durastanti, C.; Fantaye, Y.; Hansen, F.; Marinucci, D.; Pesenson, I. Z.

    2014-11-01

    We present here a simple construction of a wavelet system for the three-dimensional ball, which we label radial 3D needlets. The construction envisages a data collection environment in which an observer located at the center of the ball is surrounded by concentric spheres with the same pixelization at different radial distances, for any given resolution. The system is then obtained by weighting the projector operator built on the corresponding set of eigenfunctions and performing a discretization step which turns out to be computationally very convenient. The resulting wavelets can be shown to have very good localization properties in the real and harmonic domain; their implementation is computationally very convenient, and they allow for exact reconstruction as they form a tight frame system. Our theoretical results are supported by an extensive numerical analysis.

  12. 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

  13. 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.

  14. 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.

  15. ICER-3D Hyperspectral Image Compression Software

    NASA Technical Reports Server (NTRS)

    Xie, Hua; Kiely, Aaron; Klimesh, matthew; Aranki, Nazeeh

    2010-01-01

    Software has been developed to implement the ICER-3D algorithm. ICER-3D effects progressive, three-dimensional (3D), wavelet-based compression of hyperspectral images. If a compressed data stream is truncated, the progressive nature of the algorithm enables reconstruction of hyperspectral data at fidelity commensurate with the given data volume. The ICER-3D software is capable of providing either lossless or lossy compression, and incorporates an error-containment scheme to limit the effects of data loss during transmission. The compression algorithm, which was derived from the ICER image compression algorithm, includes wavelet-transform, context-modeling, and entropy coding subalgorithms. The 3D wavelet decomposition structure used by ICER-3D exploits correlations in all three dimensions of sets of hyperspectral image data, while facilitating elimination of spectral ringing artifacts, using a technique summarized in "Improving 3D Wavelet-Based Compression of Spectral Images" (NPO-41381), NASA Tech Briefs, Vol. 33, No. 3 (March 2009), page 7a. Correlation is further exploited by a context-modeling subalgorithm, which exploits spectral dependencies in the wavelet-transformed hyperspectral data, using an algorithm that is summarized in "Context Modeler for Wavelet Compression of Hyperspectral Images" (NPO-43239), which follows this article. An important feature of ICER-3D is a scheme for limiting the adverse effects of loss of data during transmission. In this scheme, as in the similar scheme used by ICER, the spatial-frequency domain is partitioned into rectangular error-containment regions. In ICER-3D, the partitions extend through all the wavelength bands. The data in each partition are compressed independently of those in the other partitions, so that loss or corruption of data from any partition does not affect the other partitions. Furthermore, because compression is progressive within each partition, when data are lost, any data from that partition received

  16. 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.

  17. The EISCAT_3D Science Case

    NASA Astrophysics Data System (ADS)

    Tjulin, A.; Mann, I.; McCrea, I.; Aikio, A. T.

    2013-05-01

    projection in the high-latitude ionosphere. EISCAT_3D can also be used to study solar system properties. Thanks to the high power and great accuracy, mapping of objects like the Moon and asteroids is possible. With the high power and large antenna aperture, incoherent scatter radars can be extraordinarily good monitors of extraterrestrial dust and its interaction with the atmosphere. Although incoherent scatter radars, such as EISCAT_3D, are few in number, the power and versatility of their measurement technique mean that they can measure parameters which are not obtainable otherwise, and thus also be a cornerstone in the international efforts to measure and predict space weather effects. Finally, over the years the EISCAT radars have served as a testbed for new ideas in radar coding and data analysis. EISCAT_3D will be the first of a new generation of "software radars" whose advanced capabilities will be realised not by its hardware but by the flexibility and adaptability of the scheduling, beam-forming, signal processing and analysis software used to control the radar and process its data. Thus, new techniques will be developed into standard observing applications for implementation in the next generation of software radars.

  18. Remote listening and passive acoustic detection in a 3-D environment

    NASA Astrophysics Data System (ADS)

    Barnhill, Colin

    Teleconferencing environments are a necessity in business, education and personal communication. They allow for the communication of information to remote locations without the need for travel and the necessary time and expense required for that travel. Visual information can be communicated using cameras and monitors. The advantage of visual communication is that an image can capture multiple objects and convey them, using a monitor, to a large group of people regardless of the receiver's location. This is not the case for audio. Currently, most experimental teleconferencing systems' audio is based on stereo recording and reproduction techniques. The problem with this solution is that it is only effective for one or two receivers. To accurately capture a sound environment consisting of multiple sources and to recreate that for a group of people is an unsolved problem. This work will focus on new methods of multiple source 3-D environment sound capture and applications using these captured environments. Using spherical microphone arrays, it is now possible to capture a true 3-D environment A spherical harmonic transform on the array's surface allows us to determine the basis functions (spherical harmonics) for all spherical wave solutions (up to a fixed order). This spherical harmonic decomposition (SHD) allows us to not only look at the time and frequency characteristics of an audio signal but also the spatial characteristics of an audio signal. In this way, a spherical harmonic transform is analogous to a Fourier transform in that a Fourier transform transforms a signal into the frequency domain and a spherical harmonic transform transforms a signal into the spatial domain. The SHD also decouples the input signals from the microphone locations. Using the SHD of a soundfield, new algorithms are available for remote listening, acoustic detection, and signal enhancement The new algorithms presented in this paper show distinct advantages over previous detection and

  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. 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.

  1. 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.

  2. Object recognition using cylindrical harmonic filter.

    PubMed

    Guerrero Bermúdez, Jáder

    2004-06-28

    We present the cylindrical harmonic filter for three-dimensional (3D) discrete correlation between range data. The filter guarantees invariance of the correlation peak intensity under target rotation around z-axis. It can be considered a harmonic decomposition, in cylindrical coordinates, of the 3D Fourier spectrum of the target. Some simulation results confirm the in-plane rotation invariance and the discrimination of the filter.

  3. Counter-sniper 3D laser radar

    NASA Astrophysics Data System (ADS)

    Shepherd, Orr; LePage, Andrew J.; Wijntjes, Geert J.; Zehnpfennig, Theodore F.; Sackos, John T.; Nellums, Robert O.

    1999-01-01

    Visidyne, Inc., teaming with Sandia National Laboratories, has developed the preliminary design for an innovative scannerless 3-D laser radar capable of acquiring, tracking, and determining the coordinates of small caliber projectiles in flight with sufficient precision, so their origin can be established by back projecting their tracks to their source. The design takes advantage of the relatively large effective cross-section of a bullet at optical wavelengths. Kay to its implementation is the use of efficient, high- power laser diode arrays for illuminators and an imaging laser receiver using a unique CCD imager design, that acquires the information to establish x, y (angle-angle) and range coordinates for each bullet at very high frame rates. The detection process achieves a high degree of discrimination by using the optical signature of the bullet, solar background mitigation, and track detection. Field measurements and computer simulations have been used to provide the basis for a preliminary design of a robust bullet tracker, the Counter Sniper 3-D Laser Radar. Experimental data showing 3-D test imagery acquired by a lidar with architecture similar to that of the proposed Counter Sniper 3-D Lidar are presented. A proposed Phase II development would yield an innovative, compact, and highly efficient bullet-tracking laser radar. Such a device would meet the needs of not only the military, but also federal, state, and local law enforcement organizations.

  4. 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

  5. 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

  6. 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

  7. 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

  8. 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.

  9. Multi-MW 22.8 GHz Harmonic Multiplier - RF Power Source for High-Gradient Accelerator R&D

    SciTech Connect

    Jay L. Hirshfield

    2012-07-26

    Electrodynamic and particle simulation studies have been carried out to optimize design of a two-cavity harmonic frequency multiplier, in which a linear electron beam is energized by rotating fields near cyclotron resonance in a TE111 cavity in a uniform magnetic field, and in which the beam then radiates coherently at the nth harmonic into a TEn11 output cavity. Examples are worked out in detail for 7th and 2nd harmonic converters, showing RF-to-RF conversion efficiencies of 45% and 88%, respectively at 19.992 GHz (K-band) and 5.712 GHz (C-band), for a drive frequency of 2.856 GHz. Details are shown of RF infrastructure (S-band klystron, modulator) and harmonic converter components (drive cavity, output cavities, electron beam source and modulator, beam collector) for the two harmonic converters to be tested. Details are also given for the two-frequency (S- and C-band) coherent multi-MW test stand for RF breakdown and RF gun studies.

  10. Integrating 3D Visualization and GIS in Planning Education

    ERIC Educational Resources Information Center

    Yin, Li

    2010-01-01

    Most GIS-related planning practices and education are currently limited to two-dimensional mapping and analysis although 3D GIS is a powerful tool to study the complex urban environment in its full spatial extent. This paper reviews current GIS and 3D visualization uses and development in planning practice and education. Current literature…

  11. 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)

  12. 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…

  13. 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.

  14. 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…

  15. Volumetric 3D display using a DLP projection engine

    NASA Astrophysics Data System (ADS)

    Geng, Jason

    2012-03-01

    In this article, we describe a volumetric 3D display system based on the high speed DLPTM (Digital Light Processing) projection engine. Existing two-dimensional (2D) flat screen displays often lead to ambiguity and confusion in high-dimensional data/graphics presentation due to lack of true depth cues. Even with the help of powerful 3D rendering software, three-dimensional (3D) objects displayed on a 2D flat screen may still fail to provide spatial relationship or depth information correctly and effectively. Essentially, 2D displays have to rely upon capability of human brain to piece together a 3D representation from 2D images. Despite the impressive mental capability of human visual system, its visual perception is not reliable if certain depth cues are missing. In contrast, volumetric 3D display technologies to be discussed in this article are capable of displaying 3D volumetric images in true 3D space. Each "voxel" on a 3D image (analogous to a pixel in 2D image) locates physically at the spatial position where it is supposed to be, and emits light from that position toward omni-directions to form a real 3D image in 3D space. Such a volumetric 3D display provides both physiological depth cues and psychological depth cues to human visual system to truthfully perceive 3D objects. It yields a realistic spatial representation of 3D objects and simplifies our understanding to the complexity of 3D objects and spatial relationship among them.

  16. Higher harmonics generation in relativistic electron beam with virtual cathode

    SciTech Connect

    Kurkin, S. A. Badarin, A. A.; Koronovskii, A. A.; Hramov, A. E.

    2014-09-15

    The study of the microwave generation regimes with intense higher harmonics taking place in a high-power vircator consisting of a relativistic electron beam with a virtual cathode has been made. The characteristics of these regimes, in particular, the typical spectra and their variations with the change of the system parameters (beam current, the induction of external magnetic field) as well as physical processes occurring in the system have been analyzed by means of 3D electromagnetic simulation. It has been shown that the system under study demonstrates the tendency to the sufficient growth of the amplitudes of higher harmonics in the spectrum of current oscillations in the VC region with the increase of beam current. The obtained results allow us to consider virtual cathode oscillators as promising high power mmw-to-THz sources.

  17. [Development of a software for 3D virtual phantom design].

    PubMed

    Zou, Lian; Xie, Zhao; Wu, Qi

    2014-02-01

    In this paper, we present a 3D virtual phantom design software, which was developed based on object-oriented programming methodology and dedicated to medical physics research. This software was named Magical Phan tom (MPhantom), which is composed of 3D visual builder module and virtual CT scanner. The users can conveniently construct any complex 3D phantom, and then export the phantom as DICOM 3.0 CT images. MPhantom is a user-friendly and powerful software for 3D phantom configuration, and has passed the real scene's application test. MPhantom will accelerate the Monte Carlo simulation for dose calculation in radiation therapy and X ray imaging reconstruction algorithm research.

  18. Optical microcavity scanning 3D tomography.

    PubMed

    Di Donato, Andrea; Criante, Luigino; LoTurco, Sara; Farina, Marco

    2014-10-01

    A scanning optical microcavity is exploited to achieve lens-free 3D tomography of microfluidic channels. The microcavity, powered by a low-coherence source, is realized by approaching a cleaved fiber to few tens of micrometers over the sample. The interference of scattered waves inside the cavity shapes the transverse field distribution by focusing the beam and overcoming the diffraction limit due to the optical-fiber numerical aperture. The focusing effect is also preserved in the inner layers of the sample, allowing optical 3D tomography. Analysis of microfluidic channels was demonstrated through this noninvasive technique. Although the experimental setup recalls the well-known fiber-optic Fourier-domain common-path optical coherence tomography, the proposed method has intrinsic characteristics that distinguish it from the former one.

  19. 3D plasma camera for planetary missions

    NASA Astrophysics Data System (ADS)

    Berthomier, Matthieu; Morel, Xavier; Techer, Jean-Denis

    2014-05-01

    A new 3D field-of-view toroidal space plasma analyzer based on an innovative optical concept allows the coverage of 4π str solid angle with only two sensor heads. It fits the need of all-sky thermal plasma measurements on three-axis stabilized spacecraft which are the most commonly used platforms for planetary missions. The 3D plasma analyzer also takes advantage of the new possibilities offered by the development of an ultra low-power multi-channel charge sensitive amplifier used for the imaging detector of the instrument. We present the design and measured performances of a prototype model that will fly on a test rocket in 2014.

  20. High-power, single-frequency, continuous-wave second-harmonic-generation of ytterbium fiber laser in PPKTP and MgO:sPPLT.

    PubMed

    Kumar, S Chaitanya; Samanta, G K; Ebrahim-Zadeh, M

    2009-08-03

    Characteristics of high-power, narrow-linewidth, continuous-wave (cw) green radiation obtained by simple single-pass second-harmonic-generation (SHG) of a cw ytterbium fiber laser at 1064 nm in the nonlinear crystals of PPKTP and MgO:sPPLT are studied and compared. Temperature tuning and SHG power scaling up to nearly 10 W for input fundamental power levels up to 30 W are performed. Various contributions to thermal effects in both crystals, limiting the SHG conversion efficiency, are studied. Optimal focusing conditions and thermal management schemes are investigated to maximize SHG performance in MgO:sPPLT. Stable green output power and high spatial beam quality with M(2)<1.33 and M(2)<1.34 is achieved in MgO:sPPLT and PPKTP, respectively.

  1. The 3D-QSAR study of 110 diverse, dual binding, acetylcholinesterase inhibitors based on alignment independent descriptors (GRIND-2). The effects of conformation on predictive power and interpretability of the models.

    PubMed

    Vitorović-Todorović, Maja D; Cvijetić, Ilija N; Juranić, Ivan O; Drakulić, Branko J

    2012-09-01

    The 3D-QSAR analysis based on alignment independent descriptors (GRIND-2) was performed on the set of 110 structurally diverse, dual binding AChE reversible inhibitors. Three separate models were built, based on different conformations, generated following next criteria: (i) minimum energy conformations, (ii) conformation most similar to the co-crystalized ligand conformation, and (iii) docked conformation. We found that regardless on conformation used, all the three models had good statistic and predictivity. The models revealed the importance of protonated pyridine nitrogen of tacrine moiety for anti AChE activity, and recognized HBA and HBD interactions as highly important for the potency. This was revealed by the variables associated with protonated pyridinium nitrogen, and the two amino groups of the linker. MIFs calculated with the N1 (pyridinium nitrogen) and the DRY GRID probes in the AChE active site enabled us to establish the relationship between amino acid residues within AChE active site and the variables having high impact on models. External predictive power of the models was tested on the set of 40 AChE reversible inhibitors, most of them structurally different from the training set. Some of those compounds were tested on the different enzyme source. We found that external predictivity was highly sensitive on conformations used. Model based on docked conformations had superior predictive ability, emphasizing the need for the employment of conformations built by taking into account geometrical restrictions of AChE active site gorge.

  2. 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.

  3. Second harmonic inversion for ultrasound contrast harmonic imaging.

    PubMed

    Pasovic, Mirza; Danilouchkine, Mike; Faez, Telli; van Neer, Paul L M J; Cachard, Christian; van der Steen, Antonius F W; Basset, Olivier; de Jong, Nico

    2011-06-07

    Ultrasound contrast agents (UCAs) are small micro-bubbles that behave nonlinearly when exposed to an ultrasound wave. This nonlinear behavior can be observed through the generated higher harmonics in a back-scattered echo. In past years several techniques have been proposed to detect or image harmonics produced by UCAs. In these proposed works, the harmonics generated in the medium during the propagation of the ultrasound wave played an important role, since these harmonics compete with the harmonics generated by the micro-bubbles. We present a method for the reduction of the second harmonic generated during nonlinear-propagation-dubbed second harmonic inversion (SHI). A general expression for the suppression signals is also derived. The SHI technique uses two pulses, p' and p″, of the same frequency f(0) and the same amplitude P(0) to cancel out the second harmonic generated by nonlinearities of the medium. Simulations show that the second harmonic is reduced by 40 dB on a large axial range. Experimental SHI B-mode images, from a tissue-mimicking phantom and UCAs, show an improvement in the agent-to-tissue ratio (ATR) of 20 dB compared to standard second harmonic imaging and 13 dB of improvement in harmonic power Doppler.

  4. 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.

  5. MSV3d: database of human MisSense Variants mapped to 3D protein structure.

    PubMed

    Luu, Tien-Dao; Rusu, Alin-Mihai; Walter, Vincent; Ripp, Raymond; Moulinier, Luc; Muller, Jean; Toursel, Thierry; Thompson, Julie D; Poch, Olivier; Nguyen, Hoan

    2012-01-01

    The elucidation of the complex relationships linking genotypic and phenotypic variations to protein structure is a major challenge in the post-genomic era. We present MSV3d (Database of human MisSense Variants mapped to 3D protein structure), a new database that contains detailed annotation of missense variants of all human proteins (20 199 proteins). The multi-level characterization includes details of the physico-chemical changes induced by amino acid modification, as well as information related to the conservation of the mutated residue and its position relative to functional features in the available or predicted 3D model. Major releases of the database are automatically generated and updated regularly in line with the dbSNP (database of Single Nucleotide Polymorphism) and SwissVar releases, by exploiting the extensive Décrypthon computational grid resources. The database (http://decrypthon.igbmc.fr/msv3d) is easily accessible through a simple web interface coupled to a powerful query engine and a standard web service. The content is completely or partially downloadable in XML or flat file formats. Database URL: http://decrypthon.igbmc.fr/msv3d.

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. 3D FaceCam: a fast and accurate 3D facial imaging device for biometrics applications

    NASA Astrophysics Data System (ADS)

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

    2004-08-01

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

  12. [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.

  13. Discriminating harmonicity

    NASA Astrophysics Data System (ADS)

    Kidd, Gerald; Mason, Christine R.; Brughera, Andrew; Chiu, Chung-Yiu Peter

    2003-08-01

    Simultaneous tones that are harmonically related tend to be grouped perceptually to form a unitary auditory image. A partial that is mistuned stands out from the other tones, and harmonic complexes with different fundamental frequencies can readily be perceived as separate auditory objects. These phenomena are evidence for the strong role of harmonicity in perceptual grouping and segregation of sounds. This study measured the discriminability of harmonicity directly. In a two interval, two alternative forced-choice (2I2AFC) paradigm, the listener chose which of two sounds, signal or foil, was composed of tones that more closely matched an exact harmonic relationship. In one experiment, the signal was varied from perfectly harmonic to highly inharmonic by adding frequency perturbation to each component. The foil always had 100% perturbation. Group mean performance decreased from greater than 90% correct for 0% signal perturbation to near chance for 80% signal perturbation. In the second experiment, adding a masker presented simultaneously with the signals and foils disrupted harmonicity. Both monaural and dichotic conditions were tested. Signal level was varied relative to masker level to obtain psychometric functions from which slopes and midpoints were estimated. Dichotic presentation of these audible stimuli improved performance by 3-10 dB, due primarily to a release from ``informational masking'' by the perceptual segregation of the signal from the masker.

  14. Development of a Compact & Easy-to-Use 3-D Camera for High Speed Turbulent Flow Fields

    DTIC Science & Technology

    2013-12-05

    the 2-D Radon transform to 3-D space, i.e., the 3-D Radon transform. It is proposed that the 3-D Radon transform also has an inverse as does the 2-D...Nishimura, D.G., Principles of magnetic resonance imaging. 1996: Stanford University. 41. Deans, S.R., The Radon transform and some of its applications...2007: DoverPublications. com. 42. Averbuch, A. and Y. Shkolnisky, 3D Fourier based discrete Radon transform. Applied and Computational Harmonic

  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. Enhancement of Second-Harmonic Power Due to Self-Construction of an Anti-Guide Structure in a Thin-Film Waveguide of a Nonlinear-Optical Photoconducting Polymer

    NASA Astrophysics Data System (ADS)

    Sassa, Takafumi; Umegaki, Shinsuke

    1998-04-01

    A theoretical analysis, to explain the increase of the Cerenkov-radiation-type second-harmonic power with time in a thin-film waveguide of a nonlinear-optical photoconducting polymer, is given. An anti-guide structure, which confines both a fundamental wave and its second-harmonic wave, is gradually constructed by reorientation of the nonlinear-optical chromophores within the fundamental beam width in the thin-film polymer. The space-charge field formed by the initially weak second-harmonic wave itself causes the reorientation.

  2. An approach to 3D magnetic field calculation using numerical and differential algebra methods

    SciTech Connect

    Caspi, S.; Helm, M.; Laslett, L.J.; Brady, V.O.

    1992-07-17

    Motivated by the need for new means for specification and determination of 3D fields that are produced by electromagnetic lens elements in the region interior to coil windings and seeking to obtain techniques that will be convenient for accurate conductor placement and dynamical study of particle motion, we have conveniently gene the representation of a 2D magnetic field to 3D. We have shown that the 3 dimensioal magnetic field components of a multipole magnet in the curl-fire divergence-fire region near the axis r=0 can be derived from one dimensional functions A{sub n}(z) and their derivatives (part 1). In the region interior to coil windings of accelerator magnets the three spatial components of magnet fields can be expressed in terms of harmonic components'' proportional to functions sin (n{theta}) or cos (n{theta}) of the azimuthal angle. The r,z dependence of any such component can then be expressed in terms of powers of r times functions A{sub n}(z) and their derivatives. For twodimensional configurations B{sub z} of course is identically zero, the derivatives of A{sub n}(z) vanish, and the harmonic components of the transverse field then acquire a simple proportionality B{sub r,n} {proportional to} r{sup n-1} sin (n{theta}),B{sub {theta},n} {proportional to} r{sup n-1} cos (n{theta}), whereas in a 3-D configuration the more complex nature of the field gives rise to additional so-called psuedomultipole'' components as judged by additional powers of r required in the development of the field. Computation of the 3-D magnetic field arising at a sequence of field points, as a direct result of a specified current configuration or coil geometry, can be calculated explicitly through use of the Biot-Savart law and from such data the coefficients can then be derived for a general development of the type indicated above. We indicate, discuss, and illustrate two means by which this development may be performed.

  3. Glnemo2: Interactive Visualization 3D Program

    NASA Astrophysics Data System (ADS)

    Lambert, Jean-Charles

    2011-10-01

    Glnemo2 is an interactive 3D visualization program developed in C++ using the OpenGL library and Nokia QT 4.X API. It displays in 3D the particles positions of the different components of an nbody snapshot. It quickly gives a lot of information about the data (shape, density area, formation of structures such as spirals, bars, or peanuts). It allows for in/out zooms, rotations, changes of scale, translations, selection of different groups of particles and plots in different blending colors. It can color particles according to their density or temperature, play with the density threshold, trace orbits, display different time steps, take automatic screenshots to make movies, select particles using the mouse, and fly over a simulation using a given camera path. All these features are accessible from a very intuitive graphic user interface. Glnemo2 supports a wide range of input file formats (Nemo, Gadget 1 and 2, phiGrape, Ramses, list of files, realtime gyrfalcON simulation) which are automatically detected at loading time without user intervention. Glnemo2 uses a plugin mechanism to load the data, so that it is easy to add a new file reader. It's powered by a 3D engine which uses the latest OpenGL technology, such as shaders (glsl), vertex buffer object, frame buffer object, and takes in account the power of the graphic card used in order to accelerate the rendering. With a fast GPU, millions of particles can be rendered in real time. Glnemo2 runs on Linux, Windows (using minGW compiler), and MaxOSX, thanks to the QT4API.

  4. 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.

  5. 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.

  6. 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

  7. 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

  8. 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

  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 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

  10. 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.

  11. Extended range harmonic filter

    NASA Technical Reports Server (NTRS)

    Jankowski, H.; Geia, A. J.; Allen, C. C.

    1973-01-01

    Two types of filters, leaky-wall and open-guide, are combined into single component. Combination gives 10 db or greater additional attenuation to fourth and higher harmonics, at expense of increasing loss of fundamental frequency by perhaps 0.05 to 0.08 db. Filter is applicable to all high power microwave transmitters, but is especially desirable for satellite transmitters.

  12. 3D printing of functional biomaterials for tissue engineering.

    PubMed

    Zhu, Wei; Ma, Xuanyi; Gou, Maling; Mei, Deqing; Zhang, Kang; Chen, Shaochen

    2016-08-01

    3D printing is emerging as a powerful tool for tissue engineering by enabling 3D cell culture within complex 3D biomimetic architectures. This review discusses the prevailing 3D printing techniques and their most recent applications in building tissue constructs. The work associated with relatively well-known inkjet and extrusion-based bioprinting is presented with the latest advances in the fields. Emphasis is put on introducing two relatively new light-assisted bioprinting techniques, including digital light processing (DLP)-based bioprinting and laser based two photon polymerization (TPP) bioprinting. 3D bioprinting of vasculature network is particularly discussed for its foremost significance in maintaining tissue viability and promoting functional maturation. Limitations to current bioprinting approaches, as well as future directions of bioprinting functional tissues are also discussed.

  13. Period-doubling bifurcation in two-stage power factor correction converters using the method of incremental harmonic balance and Floquet theory

    NASA Astrophysics Data System (ADS)

    Wang, Fa-Qiang; Zhang, Hao; Ma, Xi-Kui

    2012-02-01

    In this paper, period-doubling bifurcation in a two-stage power factor correction converter is analyzed by using the method of incremental harmonic balance (IHB) and Floquet theory. A two-stage power factor correction converter typically employs a cascade configuration of a pre-regulator boost power factor correction converter with average current mode control to achieve a near unity power factor and a tightly regulated post-regulator DC—DC Buck converter with voltage feedback control to regulate the output voltage. Based on the assumption that the tightly regulated post-regulator DC—DC Buck converter is represented as a constant power sink and some other assumptions, the simplified model of the two-stage power factor correction converter is derived and its approximate periodic solution is calculated by the method of IHB. And then, the stability of the system is investigated by using Floquet theory and the stable boundaries are presented on the selected parameter spaces. Finally, some experimental results are given to confirm the effectiveness of the theoretical analysis.

  14. Residual thermal stress of a mounted KDP crystal after cooling and its effects on second harmonic generation of a high-average-power laser

    NASA Astrophysics Data System (ADS)

    Su, Ruifeng; Liu, Haitao; Liang, Yingchun; Yu, Fuli

    2017-01-01

    Thermal problems are huge challenges for solid state lasers that are interested in high output power, cooling of the nonlinear optics is insufficient to completely solve the problem of thermally induced stress, as residual thermal stress remains after cooling, which is first proposed, to the best of our knowledge. In this paper a comprehensive model incorporating principles of thermodynamics, mechanics and optics is proposed, and it is used to study the residual thermal stress of a mounted KDP crystal after cooling process from mechanical perspective, along with the effects of the residual thermal stress on the second harmonic generation (SHG) efficiency of a high-average-power laser. Effects of the structural parameters of the mounting configuration of the KDP crystal on the residual thermal stress are characterized, as well as the SHG efficiency. The numerical results demonstrate the feasibility of solving the problems of residual thermal stress from the perspective on structural design of mounting configuration.

  15. 3D Subharmonic Ultrasound Imaging In Vitro and In Vivo

    PubMed Central

    Eisenbrey, John R.; Sridharan, Anush; Machado, Priscilla; Zhao, Hongjia; Halldorsdottir, Valgerdur G.; Dave, Jaydev K.; Liu, Ji-Bin; Park, Suhyun; Dianis, Scott; Wallace, Kirk; Thomenius, Kai E.; Forsberg, F.

    2012-01-01

    Rationale and Objectives While contrast-enhanced ultrasound imaging techniques such as harmonic imaging (HI) have evolved to reduce tissue signals using the nonlinear properties of the contrast agent, levels of background suppression have been mixed. Subharmonic imaging (SHI) offers near-complete tissue suppression by centering the receive bandwidth at half the transmitting frequency. In this work we demonstrate the feasibility of 3D SHI and compare it to 3D HI. Materials and Methods 3D HI and SHI were implemented on a Logiq 9 ultrasound scanner (GE Healthcare, Milwaukee, Wisconsin) with a 4D10L probe. Four-cycle SHI was implemented to transmit at 5.8 MHz and receive at 2.9 MHz, while 2-cycle HI was implemented to transmit at 5 MHz and receive at 10 MHz. The ultrasound contrast agent Definity (Lantheus Medical Imaging, North Billerica, MA) was imaged within a flow phantom and the lower pole of two canine kidneys in both HI and SHI modes. Contrast to tissue ratios (CTR) and rendered images were compared offline. Results SHI resulted in significant improvement in CTR levels relative to HI both in vitro (12.11±0.52 vs. 2.67±0.77, p<0.001) and in vivo (5.74±1.92 vs. 2.40±0.48, p=0.04). Rendered 3D SHI images provided better tissue suppression and a greater overall view of vessels in a flow phantom and canine renal vasculature. Conclusions The successful implementation of SHI in 3D allows imaging of vascular networks over a heterogeneous sample volume and should improve future diagnostic accuracy. Additionally, 3D SHI provides improved CTR values relative to 3D HI. PMID:22464198

  16. 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.

  17. Development of visual 3D virtual environment for control software

    NASA Technical Reports Server (NTRS)

    Hirose, Michitaka; Myoi, Takeshi; Amari, Haruo; Inamura, Kohei; Stark, Lawrence

    1991-01-01

    Virtual environments for software visualization may enable complex programs to be created and maintained. A typical application might be for control of regional electric power systems. As these encompass broader computer networks than ever, construction of such systems becomes very difficult. Conventional text-oriented environments are useful in programming individual processors. However, they are obviously insufficient to program a large and complicated system, that includes large numbers of computers connected to each other; such programming is called 'programming in the large.' As a solution for this problem, the authors are developing a graphic programming environment wherein one can visualize complicated software in virtual 3D world. One of the major features of the environment is the 3D representation of concurrent process. 3D representation is used to supply both network-wide interprocess programming capability (capability for 'programming in the large') and real-time programming capability. The authors' idea is to fuse both the block diagram (which is useful to check relationship among large number of processes or processors) and the time chart (which is useful to check precise timing for synchronization) into a single 3D space. The 3D representation gives us a capability for direct and intuitive planning or understanding of complicated relationship among many concurrent processes. To realize the 3D representation, a technology to enable easy handling of virtual 3D object is a definite necessity. Using a stereo display system and a gesture input device (VPL DataGlove), our prototype of the virtual workstation has been implemented. The workstation can supply the 'sensation' of the virtual 3D space to a programmer. Software for the 3D programming environment is implemented on the workstation. According to preliminary assessments, a 50 percent reduction of programming effort is achieved by using the virtual 3D environment. The authors expect that the 3D

  18. 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.

  19. 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.

  20. 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.

  1. 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

  2. 3D Printing: Print the future of ophthalmology.

    PubMed

    Huang, Wenbin; Zhang, Xiulan

    2014-08-26

    The three-dimensional (3D) printer is a new technology that creates physical objects from digital files. Recent technological advances in 3D printing have resulted in increased use of this technology in the medical field, where it is beginning to revolutionize medical and surgical possibilities. It is already providing medicine with powerful tools that facilitate education, surgical planning, and organ transplantation research. A good understanding of this technology will be beneficial to ophthalmologists. The potential applications of 3D printing in ophthalmology, both current and future, are explored in this article.

  3. High-power 355 nm third-harmonic generation with effective walk-off compensation of LBO

    NASA Astrophysics Data System (ADS)

    Yan, Xingpeng; Liu, Qiang; Pei, Chuang; Wang, Dongsheng; Gong, Mali

    2014-04-01

    Walk-off compensation using wedged cut type-II LBO was investigated theoretically and experimentally. An algorithm is proposed to find the optimized wedged cut angle to compensate the walk-off effect completely. Using a pulsed Nd:Y V O4 MOPA laser as the fundamental frequency infrared (IR) source, 36.3 W 355 nm frequency converted ultraviolet (UV) light was obtained using an optimized wedged cut type-II LBO for walk-off compensated third-harmonic generation (THG), giving a conversion efficiency of 37.1% from IR to UV. A comparative experiment using a conventional cut type-II LBO was also implemented. The results indicate that optimized wedged cutting of type-II LBO is an effective approach for walk-off compensation in efficient THG. The output performance of angle and temperature tuning for wedged cut type-II LBO was also investigated.

  4. 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.

  5. 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

  6. 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.

  7. [Evaluation of Motion Sickness Induced by 3D Video Clips].

    PubMed

    Matsuura, Yasuyuki; Takada, Hiroki

    2016-01-01

    The use of stereoscopic images has been spreading rapidly. Nowadays, stereoscopic movies are nothing new to people. Stereoscopic systems date back to 280 A.D. when Euclid first recognized the concept of depth perception by humans. Despite the increase in the production of three-dimensional (3D) display products and many studies on stereoscopic vision, the effect of stereoscopic vision on the human body has been insufficiently understood. However, symptoms such as eye fatigue and 3D sickness have been the concerns when viewing 3D films for a prolonged period of time; therefore, it is important to consider the safety of viewing virtual 3D contents as a contribution to society. It is generally explained to the public that accommodation and convergence are mismatched during stereoscopic vision and that this is the main reason for the visual fatigue and visually induced motion sickness (VIMS) during 3D viewing. We have devised a method to simultaneously measure lens accommodation and convergence. We used this simultaneous measurement device to characterize 3D vision. Fixation distance was compared between accommodation and convergence during the viewing of 3D films with repeated measurements. Time courses of these fixation distances and their distributions were compared in subjects who viewed 2D and 3D video clips. The results indicated that after 90 s of continuously viewing 3D images, the accommodative power does not correspond to the distance of convergence. In this paper, remarks on methods to measure the severity of motion sickness induced by viewing 3D films are also given. From the epidemiological viewpoint, it is useful to obtain novel knowledge for reduction and/or prevention of VIMS. We should accumulate empirical data on motion sickness, which may contribute to the development of relevant fields in science and technology.

  8. High-power ultraviolet 278 nm laser from fourth-harmonic generation of a Nd:YAG laser in CsB3O5.

    PubMed

    Wang, Zhichao; Yang, Feng; Zhang, Guochun; Bo, Yong; Liu, Shanshan; Xie, Shiyong; Xu, Yiting; Zong, Nan; Li, Fangqin; Liu, Biaolong; Xu, Jialin; Peng, Qinjun; Zhang, Jingyuan; Cui, Dafu; Wu, Yicheng; Xu, Zuyan

    2012-06-15

    We demonstrate a high-power UV 278 nm laser by fourth-harmonic generation (FHG) of a 1112 nm Nd:YAG laser in a nonlinear optical (NLO) crystal CsB3O5 (CBO) for the first time, to our best knowledge. A 30 W level diode-pumped Q-switched Nd:YAG laser at 1112 nm with beam quality factor M2=1.2 was used as the fundamental light source at a pulse width of 500 ns. With an LiB3O5 crystal, the 1112 nm laser was first frequency-doubled to 556 nm with an average output power of 13.5 W. It was then frequency doubled again in a CBO crystal to obtain the FHG output at 278 nm. The maximum average output power of the 278 nm laser is up to 1.5 W. The results demonstrated that CBO crystal is a promising NLO material for UV high-power lasers below 300 nm.

  9. [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.

  10. 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.

  11. Design of an Ultra-Efficient GaN High Power Amplifier for Radar Front-Ends Using Active Harmonic Load-Pull

    NASA Technical Reports Server (NTRS)

    Thrivikraman, Tushar; Hoffman, James

    2012-01-01

    This work presents a new measurement technique, mixed-signal active harmonic load-pull (MSALP) developed by Anterverta-mw in partnership with Maury Microwave, that allows for wide-band ultra-high efficiency amplifiers to be designed using GaN technology. An overview of the theory behind active load-pull is presented and why load-pull is important for high-power device characterization. In addition, an example procedure is presented that outlines a methodology for amplifier design using this measurement system. Lastly, measured results of a 10W GaN amplifier are presented. This work aims to highlight the benefit of using this sophisticated measurement systems for to optimize amplifier design for real radar waveforms that in turn will simplify implementation of space-based radar systems

  12. 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

  13. 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.

  14. 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

  15. 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.…

  16. 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…

  17. 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.

  18. 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.

  19. Microscopy in 3D: a biologist’s toolbox

    PubMed Central

    Fischer, Robert S.; Wu, Yicong; Kanchanawong, Pakorn; Shroff, Hari; Waterman, Clare M.

    2012-01-01

    The power of fluorescence microscopy to study cellular structures and macromolecular complexes spans a wide range of size scales, from studies of cell behavior and function in physiological, three-dimensional (3D) environments, to understanding the molecular architecture of organelles. At each length scale, the challenge in 3D imaging is to extract the most spatial and temporal resolution possible while limiting photodamage/bleaching to living cells. A number of advancements in 3D fluorescence microscopy now offer higher resolution, improved speed, and reduced photobleaching relative to traditional point-scanning microscopy methods. Here, we discuss a few specific microscopy modalities that we believe will be particularly advantageous in imaging cells and subcellular structures in physiologically relevant 3D environments. PMID:22047760

  20. 3D object recognition in TOF data sets

    NASA Astrophysics Data System (ADS)

    Hess, Holger; Albrecht, Martin; Grothof, Markus; Hussmann, Stephan; Oikonomidis, Nikolaos; Schwarte, Rudolf

    2003-08-01

    In the last years 3D-Vision systems based on the Time-Of-Flight (TOF) principle have gained more importance than Stereo Vision (SV). TOF offers a direct depth-data acquisition, whereas SV involves a great amount of computational power for a comparable 3D data set. Due to the enormous progress in TOF-techniques, nowadays 3D cameras can be manufactured and be used for many practical applications. Hence there is a great demand for new accurate algorithms for 3D object recognition and classification. This paper presents a new strategy and algorithm designed for a fast and solid object classification. A challenging example - accurate classification of a (half-) sphere - demonstrates the performance of the developed algorithm. Finally, the transition from a general model of the system to specific applications such as Intelligent Airbag Control and Robot Assistance in Surgery are introduced. The paper concludes with the current research results in the above mentioned fields.

  1. From Microscale Devices to 3D Printing: Advances in Fabrication of 3D Cardiovascular Tissues.

    PubMed

    Borovjagin, Anton V; Ogle, Brenda M; Berry, Joel L; Zhang, Jianyi

    2017-01-06

    Current strategies for engineering cardiovascular cells and tissues have yielded a variety of sophisticated tools for studying disease mechanisms, for development of drug therapies, and for fabrication of tissue equivalents that may have application in future clinical use. These efforts are motivated by the need to extend traditional 2-dimensional (2D) cell culture systems into 3D to more accurately replicate in vivo cell and tissue function of cardiovascular structures. Developments in microscale devices and bioprinted 3D tissues are beginning to supplant traditional 2D cell cultures and preclinical animal studies that have historically been the standard for drug and tissue development. These new approaches lend themselves to patient-specific diagnostics, therapeutics, and tissue regeneration. The emergence of these technologies also carries technical challenges to be met before traditional cell culture and animal testing become obsolete. Successful development and validation of 3D human tissue constructs will provide powerful new paradigms for more cost effective and timely translation of cardiovascular tissue equivalents.

  2. Modified DSTATCOM Topology with Reduced DC Link Voltage for Reactive and Harmonic Power Compensation of Unbalanced Nonlinear Load in Distribution System

    NASA Astrophysics Data System (ADS)

    Geddada, Nagesh; Karanki, Srinivas B.; Mishra, Mahesh K.

    2014-06-01

    This paper proposes a modified four-leg distribution static compensator (DSTATCOM) topology for compensation of unbalanced and nonlinear loads in three-phase four-wire distribution system. DSTATCOM, connected in parallel to the load, supplies reactive and harmonic powers demanded by unbalanced nonlinear loads. In this proposed topology, the voltage source inverter (VSI) of DSTATCOM is connected to point of common coupling (point of interconnection of source, load, DSTATCOM) through interface inductor and series capacitance, unlike the conventional topology which consists of interface inductor alone. Load compensation with a lower value of input DC link voltage of VSI is possible in this modified topology compared to conventional topology. A comparative study on modified and conventional topologies in terms of voltage rating of inverter power switches, switching losses in VSI and power rating of input DC capacitor of VSI is presented. The detailed design aspects of DC link capacitor and interface series capacitor are also presented. The reference filter currents are generated using instantaneous symmetrical component theory and are tracked using hysteresis current control technique. A detailed simulation study is carried out, to compare the compensation performances of conventional, modified topologies using PSCAD simulator and experimental studies are done to validate the simulation results.

  3. INSTRUMENTS AND METHODS OF INVESTIGATION: Generation of high-order harmonics of high-power lasers in plasmas produced under irradiation of solid target surfaces by a prepulse

    NASA Astrophysics Data System (ADS)

    Ganeev, Rashid A.

    2009-01-01

    Research on high-order harmonic generation in laser-produced plasmas is reviewed. We analyze the conditions for the generation of harmonics (up to the 101st order, λ = 7.9 nm) in the propagation of laser radiation through a weakly ionized plasma prepared by irradiating the surfaces of different targets with a laser prepulse. We discuss the findings of investigations into the resonance intensity enhancement of individual harmonics in a number of plasma formations, which have demonstrated a substantial increase in the conversion efficiency in the plateau region of the harmonic-order distribution (in particular, of the 13th harmonic in indium plasmas with the efficiency 10-4). We review the results of investigations of harmonic generation in nanoparticle-containing plasmas. Different techniques for increasing the intensity and order of the generated harmonics are discussed.

  4. 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.

  5. Harmonic engine

    DOEpatents

    Bennett, Charles L.

    2009-10-20

    A high efficiency harmonic engine based on a resonantly reciprocating piston expander that extracts work from heat and pressurizes working fluid in a reciprocating piston compressor. The engine preferably includes harmonic oscillator valves capable of oscillating at a resonant frequency for controlling the flow of working fluid into and out of the expander, and also preferably includes a shunt line connecting an expansion chamber of the expander to a buffer chamber of the expander for minimizing pressure variations in the fluidic circuit of the engine. The engine is especially designed to operate with very high temperature input to the expander and very low temperature input to the compressor, to produce very high thermal conversion efficiency.

  6. 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.

  7. 3D galaxy clustering with future wide-field surveys: Advantages of a spherical Fourier-Bessel analysis

    NASA Astrophysics Data System (ADS)

    Lanusse, F.; Rassat, A.; Starck, J.-L.

    2015-06-01

    Context. Upcoming spectroscopic galaxy surveys are extremely promising to help in addressing the major challenges of cosmology, in particular in understanding the nature of the dark universe. The strength of these surveys, naturally described in spherical geometry, comes from their unprecedented depth and width, but an optimal extraction of their three-dimensional information is of utmost importance to best constrain the properties of the dark universe. Aims: Although there is theoretical motivation and novel tools to explore these surveys using the 3D spherical Fourier-Bessel (SFB) power spectrum of galaxy number counts Cℓ(k,k'), most survey optimisations and forecasts are based on the tomographic spherical harmonics power spectrum C(ij)_ℓ. The goal of this paper is to perform a new investigation of the information that can be extracted from these two analyses in the context of planned stage IV wide-field galaxy surveys. Methods: We compared tomographic and 3D SFB techniques by comparing the forecast cosmological parameter constraints obtained from a Fisher analysis. The comparison was made possible by careful and coherent treatment of non-linear scales in the two analyses, which makes this study the first to compare 3D SFB and tomographic constraints on an equal footing. Nuisance parameters related to a scale- and redshift-dependent galaxy bias were also included in the computation of the 3D SFB and tomographic power spectra for the first time. Results: Tomographic and 3D SFB methods can recover similar constraints in the absence of systematics. This requires choosing an optimal number of redshift bins for the tomographic analysis, which we computed to be N = 26 for zmed ≃ 0.4, N = 30 for zmed ≃ 1.0, and N = 42 for zmed ≃ 1.7. When marginalising over nuisance parameters related to the galaxy bias, the forecast 3D SFB constraints are less affected by this source of systematics than the tomographic constraints. In addition, the rate of increase of the

  8. Density functional theory optimized basis sets for gradient corrected functionals: 3d transition metal systems.

    PubMed

    Calaminici, Patrizia; Janetzko, Florian; Köster, Andreas M; Mejia-Olvera, Roberto; Zuniga-Gutierrez, Bernardo

    2007-01-28

    Density functional theory optimized basis sets for gradient corrected functionals for 3d transition metal atoms are presented. Double zeta valence polarization and triple zeta valence polarization basis sets are optimized with the PW86 functional. The performance of the newly optimized basis sets is tested in atomic and molecular calculations. Excitation energies of 3d transition metal atoms, as well as electronic configurations, structural parameters, dissociation energies, and harmonic vibrational frequencies of a large number of molecules containing 3d transition metal elements, are presented. The obtained results are compared with available experimental data as well as with other theoretical data from the literature.

  9. VISRAD, 3-D Target Design and Radiation Simulation Code

    NASA Astrophysics Data System (ADS)

    Golovkin, Igor; Macfarlane, Joseph; Golovkina, Viktoriya

    2016-10-01

    The 3-D view factor code VISRAD is widely used in designing HEDP experiments at major laser and pulsed-power facilities, including NIF, OMEGA, OMEGA-EP, ORION, LMJ, Z, and PLX. It simulates target designs by generating a 3-D grid of surface elements, utilizing a variety of 3-D primitives and surface removal algorithms, and can be used to compute the radiation flux throughout the surface element grid by computing element-to-element view factors and solving power balance equations. Target set-up and beam pointing are facilitated by allowing users to specify positions and angular orientations using a variety of coordinates systems (e.g., that of any laser beam, target component, or diagnostic port). Analytic modeling for laser beam spatial profiles for OMEGA DPPs and NIF CPPs is used to compute laser intensity profiles throughout the grid of surface elements. We will discuss recent improvements to the software package and plans for future developments.

  10. Waveguide harmonic damper for klystron amplifier.

    SciTech Connect

    Kang, Y.

    1998-10-27

    A waveguide harmonic damper was designed for removing the harmonic frequency power from the klystron amplifiers of the APS linac. Straight coaxial probe antennas are used in a rectangular waveguide to form a damper. A linear array of the probe antennas is used on a narrow wall of the rectangular waveguide for damping klystron harmonics while decoupling the fundamental frequency in dominent TE{sub 01} mode. The klystron harmonics can exist in the waveguide as waveguide higher-order modes above cutoff. Computer simulations are made to investigate the waveguide harmonic damping characteristics of the damper.

  11. 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.

  12. 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.

  13. 3D shape analysis for early diagnosis of malignant lung nodules.

    PubMed

    El-Baz, Ayman; Nitzken, Matthew; Elnakib, Ahmed; Khalifa, Fahmi; Gimel'farb, Georgy; Falk, Robert; El-Ghar, Mohamed Abou

    2011-01-01

    An alternative method of diagnosing malignant lung nodules by their shape, rather than conventional growth rate, is proposed. The 3D surfaces of the detected lung nodules are delineated by spherical harmonic analysis that represents a 3D surface of the lung nodule supported by the unit sphere with a linear combination of special basis functions, called Spherical Harmonics (SHs). The proposed 3D shape analysis is carried out in five steps: (i) 3D lung nodule segmentation with a deformable 3D boundary controlled by a new prior visual appearance model; (ii) 3D Delaunay triangulation to construct a 3D mesh model of the segmented lung nodule surface; (iii) mapping this model to the unit sphere; (iv) computing the SHs for the surface; and (v) determining the number of the SHs to delineate the lung nodule. We describe the lung nodule shape complexity with a new shape index, the estimated number of the SHs, and use it for the K-nearest classification into malignant and benign lung nodules. Preliminary experiments on 327 lung nodules (153 malignant and 174 benign) resulted in a classification accuracy of 93.6%, showing that the proposed method is a promising supplement to current technologies for the early diagnosis of lung cancer.

  14. 3D shape analysis for early diagnosis of malignant lung nodules.

    PubMed

    El-Bazl, Ayman; Nitzken, Matthew; Khalifa, Fahmi; Elnakib, Ahmed; Gimel'farb, Georgy; Falk, Robert; El-Ghar, Mohammed Abo

    2011-01-01

    An alternative method for diagnosing malignant lung nodules by their shape rather than conventional growth rate is proposed. The 3D surfaces of the detected lung nodules are delineated by spherical harmonic analysis, which represents a 3D surface of the lung nodule supported by the unit sphere with a linear combination of special basis functions, called spherical harmonics (SHs). The proposed 3D shape analysis is carried out in five steps: (i) 3D lung nodule segmentation with a deformable 3D boundary controlled by two probabilistic visual appearance models (the learned prior and the estimated current appearance one); (ii) 3D Delaunay triangulation to construct a 3D mesh model of the segmented lung nodule surface; (iii) mapping this model to the unit sphere; (iv) computing the SHs for the surface, and (v) determining the number of the SHs to delineate the lung nodule. We describe the lung nodule shape complexity with a new shape index, the estimated number of the SHs, and use it for the K-nearest classification to distinguish malignant and benign lung nodules. Preliminary experiments on 327 lung nodules (153 malignant and 174 benign) resulted in the 93.6% correct classification (for the 95% confidence interval), showing that the proposed method is a promising supplement to current technologies for the early diagnosis of lung cancer.

  15. Automated 3D reconstruction of interiors with multiple scan views

    NASA Astrophysics Data System (ADS)

    Sequeira, Vitor; Ng, Kia C.; Wolfart, Erik; Goncalves, Joao G. M.; Hogg, David C.

    1998-12-01

    This paper presents two integrated solutions for realistic 3D model acquisition and reconstruction; an early prototype, in the form of a push trolley, and a later prototype in the form of an autonomous robot. The systems encompass all hardware and software required, from laser and video data acquisition, processing and output of texture-mapped 3D models in VRML format, to batteries for power supply and wireless network communications. The autonomous version is also equipped with a mobile platform and other sensors for the purpose of automatic navigation. The applications for such a system range from real estate and tourism (e.g., showing a 3D computer model of a property to a potential buyer or tenant) or as tool for content creation (e.g., creating 3D models of heritage buildings or producing broadcast quality virtual studios). The system can also be used in industrial environments as a reverse engineering tool to update the design of a plant, or as a 3D photo-archive for insurance purposes. The system is Internet compatible: the photo-realistic models can be accessed via the Internet and manipulated interactively in 3D using a common Web browser with a VRML plug-in. Further information and example reconstructed models are available on- line via the RESOLV web-page at http://www.scs.leeds.ac.uk/resolv/.

  16. 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.

  17. NASA VERVE: Interactive 3D Visualization Within Eclipse

    NASA Technical Reports Server (NTRS)

    Cohen, Tamar; Allan, Mark B.

    2014-01-01

    At NASA, we develop myriad Eclipse RCP applications to provide situational awareness for remote systems. The Intelligent Robotics Group at NASA Ames Research Center has developed VERVE - a high-performance, robot user interface that provides scientists, robot operators, and mission planners with powerful, interactive 3D displays of remote environments.VERVE includes a 3D Eclipse view with an embedded Java Ardor3D scenario, including SWT and mouse controls which interact with the Ardor3D camera and objects in the scene. VERVE also includes Eclipse views for exploring and editing objects in the Ardor3D scene graph, and a HUD (Heads Up Display) framework allows Growl-style notifications and other textual information to be overlayed onto the 3D scene. We use VERVE to listen to telemetry from robots and display the robots and associated scientific data along the terrain they are exploring; VERVE can be used for any interactive 3D display of data.VERVE is now open source. VERVE derives from the prior Viz system, which was developed for Mars Polar Lander (2001) and used for the Mars Exploration Rover (2003) and the Phoenix Lander (2008). It has been used for ongoing research with IRG's K10 and KRex rovers in various locations. VERVE was used on the International Space Station during two experiments in 2013 - Surface Telerobotics, in which astronauts controlled robots on Earth from the ISS, and SPHERES, where astronauts control a free flying robot on board the ISS.We will show in detail how to code with VERVE, how to interact between SWT controls to the Ardor3D scenario, and share example code.

  18. Combined diplexer and harmonic filter

    NASA Technical Reports Server (NTRS)

    Allen, C. C.

    1973-01-01

    By using two directional filters having circular waveguide filter cavities, diplexing and harmonic filtering functions can be combined into a more compact integrated waveguide assembly. Device is filter which passes power within its pass band limits, but also has a directional characteristic so power transmitted into two-port output waveguide will travel in only one direction.

  19. Power Requirements for Bi-Harmonic Amplitude and Bias Modulation Control of a Flapping Wing Micro Air Vehicle

    DTIC Science & Technology

    2013-03-01

    N Yaw Moment P Power R Wingspan RBI Rotation Matrix from the Inertial Reference Frame to the Body Frame Re Reynolds Number S Wing Area X Axial Force...Y Z ]T are the axial forces, RBI is a rotation matrix from the inertial frame to the body frame , and g is the gravitational acceleration. [41] This...with the load on the system. There is advantageous energetic expenditure when mechanical systems operate at resonance . [16] The advantage of low

  20. Research on the printability of hydrogels in 3D bioprinting

    PubMed Central

    He, Yong; Yang, FeiFei; Zhao, HaiMing; Gao, Qing; Xia, Bing; Fu, JianZhong

    2016-01-01

    As the biocompatible materials, hydrogels have been widely used in three- dimensional (3D) bioprinting/organ printing to load cell for tissue engineering. It is important to precisely control hydrogels deposition during printing the mimic organ structures. However, the printability of hydrogels about printing parameters is seldom addressed. In this paper, we systemically investigated the printability of hydrogels from printing lines (one dimensional, 1D structures) to printing lattices/films (two dimensional, 2D structures) and printing 3D structures with a special attention to the accurate printing. After a series of experiments, we discovered the relationships between the important factors such as air pressure, feedrate, or even printing distance and the printing quality of the expected structures. Dumbbell shape was observed in the lattice structures printing due to the hydrogel diffuses at the intersection. Collapses and fusion of adjacent layer would result in the error accumulation at Z direction which was an important fact that could cause printing failure. Finally, we successfully demonstrated a 3D printing hydrogel scaffold through harmonize with all the parameters. The cell viability after printing was compared with the casting and the results showed that our bioprinting method almost had no extra damage to the cells. PMID:27436509

  1. 3D tongue motion from tagged and cine MR images.

    PubMed

    Xing, Fangxu; Woo, Jonghye; Murano, Emi Z; Lee, Junghoon; Stone, Maureen; Prince, Jerry L

    2013-01-01

    Understanding the deformation of the tongue during human speech is important for head and neck surgeons and speech and language scientists. Tagged magnetic resonance (MR) imaging can be used to image 2D motion, and data from multiple image planes can be combined via post-processing to yield estimates of 3D motion. However, lacking boundary information, this approach suffers from inaccurate estimates near the tongue surface. This paper describes a method that combines two sources of information to yield improved estimation of 3D tongue motion. The method uses the harmonic phase (HARP) algorithm to extract motion from tags and diffeomorphic demons to provide surface deformation. It then uses an incompressible deformation estimation algorithm to incorporate both sources of displacement information to form an estimate of the 3D whole tongue motion. Experimental results show that use of combined information improves motion estimation near the tongue surface, a problem that has previously been reported as problematic in HARP analysis, while preserving accurate internal motion estimates. Results on both normal and abnormal tongue motions are shown.

  2. Research on the printability of hydrogels in 3D bioprinting

    NASA Astrophysics Data System (ADS)

    He, Yong; Yang, Feifei; Zhao, Haiming; Gao, Qing; Xia, Bing; Fu, Jianzhong

    2016-07-01

    As the biocompatible materials, hydrogels have been widely used in three- dimensional (3D) bioprinting/organ printing to load cell for tissue engineering. It is important to precisely control hydrogels deposition during printing the mimic organ structures. However, the printability of hydrogels about printing parameters is seldom addressed. In this paper, we systemically investigated the printability of hydrogels from printing lines (one dimensional, 1D structures) to printing lattices/films (two dimensional, 2D structures) and printing 3D structures with a special attention to the accurate printing. After a series of experiments, we discovered the relationships between the important factors such as air pressure, feedrate, or even printing distance and the printing quality of the expected structures. Dumbbell shape was observed in the lattice structures printing due to the hydrogel diffuses at the intersection. Collapses and fusion of adjacent layer would result in the error accumulation at Z direction which was an important fact that could cause printing failure. Finally, we successfully demonstrated a 3D printing hydrogel scaffold through harmonize with all the parameters. The cell viability after printing was compared with the casting and the results showed that our bioprinting method almost had no extra damage to the cells.

  3. 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

  4. 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

  5. 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

  6. 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

  7. 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

  8. 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.

  9. 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.

  10. Observation of dynamic interactions between fundamental and second-harmonic modes in a high-power sub-terahertz gyrotron operating in regimes of soft and hard self-excitation.

    PubMed

    Saito, Teruo; Tatematsu, Yoshinori; Yamaguchi, Yuusuke; Ikeuchi, Shinji; Ogasawara, Shinya; Yamada, Naoki; Ikeda, Ryosuke; Ogawa, Isamu; Idehara, Toshitaka

    2012-10-12

    Dynamic mode interaction between fundamental and second-harmonic modes has been observed in high-power sub-terahertz gyrotrons [T. Notake et al., Phys. Rev. Lett. 103, 225002 (2009); T. Saito et al. Phys. Plasmas 19, 063106 (2012)]. Interaction takes place between a parasitic fundamental or first-harmonic (FH) mode and an operating second-harmonic (SH) mode, as well as among SH modes. In particular, nonlinear excitation of the parasitic FH mode in the hard self-excitation regime with assistance of a SH mode in the soft self-excitation regime was clearly observed. Moreover, both cases of stable two-mode oscillation and oscillation of the FH mode only were observed. These observations and theoretical analyses of the dynamic behavior of the mode interaction verify the nonlinear hard self-excitation of the FH mode.

  11. 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.

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

    NASA Technical Reports Server (NTRS)

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

    1990-01-01

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

  13. Harmonic engine

    DOEpatents

    Bennett, Charles L.; Sewall, Noel; Boroa, Carl

    2014-08-19

    An engine based on a reciprocating piston engine that extracts work from pressurized working fluid. The engine includes a harmonic oscillator inlet valve capable of oscillating at a resonant frequency for controlling the flow of working fluid into of the engine. In particular, the inlet valve includes an inlet valve head and a spring arranged together as a harmonic oscillator so that the inlet valve head is moveable from an unbiased equilibrium position to a biased closed position occluding an inlet. Upon releasing the inlet valve the inlet valve head undergoes a single oscillation past the equilibrium positio to a maximum open position and returns to a biased return position close to the closed position to choke the flow and produce a pressure drop across the inlet valve causing the inlet valve to close. Protrusions carried either by the inlet valve head or piston head are used to bump open the inlet valve from the closed position and initiate the single oscillation of the inlet valve head, and protrusions carried either by the outlet valve head or piston head are used to close the outlet valve ahead of the bump opening of the inlet valve.

  14. Current drive with combined electron cyclotron wave and high harmonic fast wave in tokamak plasmas

    NASA Astrophysics Data System (ADS)

    Li, J. C.; Gong, X. Y.; Dong, J. Q.; Wang, J.; Zhang, N.; Zheng, P. W.; Yin, C. Y.

    2016-12-01

    The current driven by combined electron cyclotron wave (ECW) and high harmonic fast wave is investigated using the GENRAY/CQL3D package. It is shown that no significant synergetic current is found in a range of cases with a combined ECW and fast wave (FW). This result is consistent with a previous study [Harvey et al., in Proceedings of IAEA TCM on Fast Wave Current Drive in Reactor Scale Tokamaks (Synergy and Complimentarily with LHCD and ECRH), Arles, France, IAEA, Vienna, 1991]. However, a positive synergy effect does appear with the FW in the lower hybrid range of frequencies. This positive synergy effect can be explained using a picture of the electron distribution function induced by the ECW and a very high harmonic fast wave (helicon). The dependence of the synergy effect on the radial position of the power deposition, the wave power, the wave frequency, and the parallel refractive index is also analyzed, both numerically and physically.

  15. An aerial 3D printing test mission

    NASA Astrophysics Data System (ADS)

    Hirsch, Michael; McGuire, Thomas; Parsons, Michael; Leake, Skye; Straub, Jeremy

    2016-05-01

    This paper provides an overview of an aerial 3D printing technology, its development and its testing. This technology is potentially useful in its own right. In addition, this work advances the development of a related in-space 3D printing technology. A series of aerial 3D printing test missions, used to test the aerial printing technology, are discussed. Through completing these test missions, the design for an in-space 3D printer may be advanced. The current design for the in-space 3D printer involves focusing thermal energy to heat an extrusion head and allow for the extrusion of molten print material. Plastics can be used as well as composites including metal, allowing for the extrusion of conductive material. A variety of experiments will be used to test this initial 3D printer design. High altitude balloons will be used to test the effects of microgravity on 3D printing, as well as parabolic flight tests. Zero pressure balloons can be used to test the effect of long 3D printing missions subjected to low temperatures. Vacuum chambers will be used to test 3D printing in a vacuum environment. The results will be used to adapt a current prototype of an in-space 3D printer. Then, a small scale prototype can be sent into low-Earth orbit as a 3-U cube satellite. With the ability to 3D print in space demonstrated, future missions can launch production hardware through which the sustainability and durability of structures in space will be greatly improved.

  16. 3D analysis of the reactivity insertion accident in VVER-1000

    SciTech Connect

    Abdullayev, A. M.; Zhukov, A. I.; Slyeptsov, S. M.

    2012-07-01

    Fuel parameters such as peak enthalpy and temperature during rod ejection accident are calculated. The calculations are performed by 3D neutron kinetics code NESTLE and 3D thermal-hydraulic code VIPRE-W. Both hot zero power and hot full power cases were studied for an equilibrium cycle with Westinghouse hex fuel in VVER-1000. It is shown that the use of 3D methodology can significantly increase safety margins for current criteria and met future criteria. (authors)

  17. 3D sensors for the HL-LHC

    NASA Astrophysics Data System (ADS)

    Vázquez Furelos, D.; Carulla, M.; Cavallaro, E.; Förster, F.; Grinstein, S.; Lange, J.; López Paz, I.; Manna, M.; Pellegrini, G.; Quirion, D.; Terzo, S.

    2017-01-01

    In order to increase its discovery potential, the Large Hadron Collider (LHC) accelerator will be upgraded in the next decade. The high luminosity LHC (HL-LHC) period requires new sensor technologies to cope with increasing radiation fluences and particle rates. The ATLAS experiment will replace the entire inner tracking detector with a completely new silicon-only system. 3D pixel sensors are promising candidates for the innermost layers of the Pixel detector due to their excellent radiation hardness at low operation voltages and low power dissipation at moderate temperatures. Recent developments of 3D sensors for the HL-LHC are presented.

  18. RELAP5-3D code validation for RBMK phenomena

    SciTech Connect

    Fisher, J.E.

    1999-09-01

    The RELAP5-3D thermal-hydraulic code was assessed against Japanese Safety Experiment Loop (SEL) and Heat Transfer Loop (HTL) tests. These tests were chosen because the phenomena present are applicable to analyses of Russian RBMK reactor designs. The assessment cases included parallel channel flow fluctuation tests at reduced and normal water levels, a channel inlet pipe rupture test, and a high power, density wave oscillation test. The results showed that RELAP5-3D has the capability to adequately represent these RBMK-related phenomena.

  19. RELAP5-3D Code Validation for RBMK Phenomena

    SciTech Connect

    Fisher, James Ebberly

    1999-09-01

    The RELAP5-3D thermal-hydraulic code was assessed against Japanese Safety Experiment Loop (SEL) and Heat Transfer Loop (HTL) tests. These tests were chosen because the phenomena present are applicable to analyses of Russian RBMK reactor designs. The assessment cases included parallel channel flow fluctuation tests at reduced and normal water levels, a channel inlet pipe rupture test, and a high power, density wave oscillation test. The results showed that RELAP5-3D has the capability to adequately represent these RBMK-related phenomena.

  20. Real-Time 3D Visualization

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Butler Hine, former director of the Intelligent Mechanism Group (IMG) at Ames Research Center, and five others partnered to start Fourth Planet, Inc., a visualization company that specializes in the intuitive visual representation of dynamic, real-time data over the Internet and Intranet. Over a five-year period, the then NASA researchers performed ten robotic field missions in harsh climes to mimic the end- to-end operations of automated vehicles trekking across another world under control from Earth. The core software technology for these missions was the Virtual Environment Vehicle Interface (VEVI). Fourth Planet has released VEVI4, the fourth generation of the VEVI software, and NetVision. VEVI4 is a cutting-edge computer graphics simulation and remote control applications tool. The NetVision package allows large companies to view and analyze in virtual 3D space such things as the health or performance of their computer network or locate a trouble spot on an electric power grid. Other products are forthcoming. Fourth Planet is currently part of the NASA/Ames Technology Commercialization Center, a business incubator for start-up companies.

  1. Integration of real-time 3D image acquisition and multiview 3D display

    NASA Astrophysics Data System (ADS)

    Zhang, Zhaoxing; Geng, Zheng; Li, Tuotuo; Li, Wei; Wang, Jingyi; Liu, Yongchun

    2014-03-01

    Seamless integration of 3D acquisition and 3D display systems offers enhanced experience in 3D visualization of the real world objects or scenes. The vivid representation of captured 3D objects displayed on a glasses-free 3D display screen could bring the realistic viewing experience to viewers as if they are viewing real-world scene. Although the technologies in 3D acquisition and 3D display have advanced rapidly in recent years, effort is lacking in studying the seamless integration of these two different aspects of 3D technologies. In this paper, we describe our recent progress on integrating a light-field 3D acquisition system and an autostereoscopic multiview 3D display for real-time light field capture and display. This paper focuses on both the architecture design and the implementation of the hardware and the software of this integrated 3D system. A prototype of the integrated 3D system is built to demonstrate the real-time 3D acquisition and 3D display capability of our proposed system.

  2. Immersive 3D Geovisualization in Higher Education

    ERIC Educational Resources Information Center

    Philips, Andrea; Walz, Ariane; Bergner, Andreas; Graeff, Thomas; Heistermann, Maik; Kienzler, Sarah; Korup, Oliver; Lipp, Torsten; Schwanghart, Wolfgang; Zeilinger, Gerold

    2015-01-01

    In this study, we investigate how immersive 3D geovisualization can be used in higher education. Based on MacEachren and Kraak's geovisualization cube, we examine the usage of immersive 3D geovisualization and its usefulness in a research-based learning module on flood risk, called GEOSimulator. Results of a survey among participating students…

  3. A 3D Geostatistical Mapping Tool

    SciTech Connect

    Weiss, W. W.; Stevenson, Graig; Patel, Ketan; Wang, Jun

    1999-02-09

    This software provides accurate 3D reservoir modeling tools and high quality 3D graphics for PC platforms enabling engineers and geologists to better comprehend reservoirs and consequently improve their decisions. The mapping algorithms are fractals, kriging, sequential guassian simulation, and three nearest neighbor methods.

  4. 3D Printing. What's the Harm?

    ERIC Educational Resources Information Center

    Love, Tyler S.; Roy, Ken

    2016-01-01

    Health concerns from 3D printing were first documented by Stephens, Azimi, Orch, and Ramos (2013), who found that commercially available 3D printers were producing hazardous levels of ultrafine particles (UFPs) and volatile organic compounds (VOCs) when plastic materials were melted through the extruder. UFPs are particles less than 100 nanometers…

  5. Topology dictionary for 3D video understanding.

    PubMed

    Tung, Tony; Matsuyama, Takashi

    2012-08-01

    This paper presents a novel approach that achieves 3D video understanding. 3D video consists of a stream of 3D models of subjects in motion. The acquisition of long sequences requires large storage space (2 GB for 1 min). Moreover, it is tedious to browse data sets and extract meaningful information. We propose the topology dictionary to encode and describe 3D video content. The model consists of a topology-based shape descriptor dictionary which can be generated from either extracted patterns or training sequences. The model relies on 1) topology description and classification using Reeb graphs, and 2) a Markov motion graph to represent topology change states. We show that the use of Reeb graphs as the high-level topology descriptor is relevant. It allows the dictionary to automatically model complex sequences, whereas other strategies would require prior knowledge on the shape and topology of the captured subjects. Our approach serves to encode 3D video sequences, and can be applied for content-based description and summarization of 3D video sequences. Furthermore, topology class labeling during a learning process enables the system to perform content-based event recognition. Experiments were carried out on various 3D videos. We showcase an application for 3D video progressive summarization using the topology dictionary.

  6. 3D elastic control for mobile devices.

    PubMed

    Hachet, Martin; Pouderoux, Joachim; Guitton, Pascal

    2008-01-01

    To increase the input space of mobile devices, the authors developed a proof-of-concept 3D elastic controller that easily adapts to mobile devices. This embedded device improves the completion of high-level interaction tasks such as visualization of large documents and navigation in 3D environments. It also opens new directions for tomorrow's mobile applications.

  7. 3D Printing of Molecular Models

    ERIC Educational Resources Information Center

    Gardner, Adam; Olson, Arthur

    2016-01-01

    Physical molecular models have played a valuable role in our understanding of the invisible nano-scale world. We discuss 3D printing and its use in producing models of the molecules of life. Complex biomolecular models, produced from 3D printed parts, can demonstrate characteristics of molecular structure and function, such as viral self-assembly,…

  8. 3D Printed Block Copolymer Nanostructures

    ERIC Educational Resources Information Center

    Scalfani, Vincent F.; Turner, C. Heath; Rupar, Paul A.; Jenkins, Alexander H.; Bara, Jason E.

    2015-01-01

    The emergence of 3D printing has dramatically advanced the availability of tangible molecular and extended solid models. Interestingly, there are few nanostructure models available both commercially and through other do-it-yourself approaches such as 3D printing. This is unfortunate given the importance of nanotechnology in science today. In this…

  9. Infrastructure for 3D Imaging Test Bed

    DTIC Science & Technology

    2007-05-11

    analysis. (c.) Real time detection & analysis of human gait: using a video camera we capture walking human silhouette for pattern modeling and gait ... analysis . Fig. 5 shows the scanning result result that is fed into a Geo-magic software tool for 3D meshing. Fig. 5: 3D scanning result In

  10. Wow! 3D Content Awakens the Classroom

    ERIC Educational Resources Information Center

    Gordon, Dan

    2010-01-01

    From her first encounter with stereoscopic 3D technology designed for classroom instruction, Megan Timme, principal at Hamilton Park Pacesetter Magnet School in Dallas, sensed it could be transformative. Last spring, when she began pilot-testing 3D content in her third-, fourth- and fifth-grade classrooms, Timme wasn't disappointed. Students…

  11. Stereo 3-D Vision in Teaching Physics

    ERIC Educational Resources Information Center

    Zabunov, Svetoslav

    2012-01-01

    Stereo 3-D vision is a technology used to present images on a flat surface (screen, paper, etc.) and at the same time to create the notion of three-dimensional spatial perception of the viewed scene. A great number of physical processes are much better understood when viewed in stereo 3-D vision compared to standard flat 2-D presentation. The…

  12. Pathways for Learning from 3D Technology

    ERIC Educational Resources Information Center

    Carrier, L. Mark; Rab, Saira S.; Rosen, Larry D.; Vasquez, Ludivina; Cheever, Nancy A.

    2012-01-01

    The purpose of this study was to find out if 3D stereoscopic presentation of information in a movie format changes a viewer's experience of the movie content. Four possible pathways from 3D presentation to memory and learning were considered: a direct connection based on cognitive neuroscience research; a connection through "immersion"…

  13. 3D, or Not to Be?

    ERIC Educational Resources Information Center

    Norbury, Keith

    2012-01-01

    It may be too soon for students to be showing up for class with popcorn and gummy bears, but technology similar to that behind the 3D blockbuster movie "Avatar" is slowly finding its way into college classrooms. 3D classroom projectors are taking students on fantastic voyages inside the human body, to the ruins of ancient Greece--even to faraway…

  14. Static & Dynamic Response of 3D Solids

    SciTech Connect

    Lin, Jerry

    1996-07-15

    NIKE3D is a large deformations 3D finite element code used to obtain the resulting displacements and stresses from multi-body static and dynamic structural thermo-mechanics problems with sliding interfaces. Many nonlinear and temperature dependent constitutive models are available.

  15. Harmonic generation with a dual frequency pulse.

    PubMed

    Keravnou, Christina P; Averkiou, Michalakis A

    2014-05-01

    Nonlinear imaging was implemented in commercial ultrasound systems over the last 15 years offering major advantages in many clinical applications. In this work, pulsing schemes coupled with a dual frequency pulse are presented. The pulsing schemes considered were pulse inversion, power modulation, and power modulated pulse inversion. The pulse contains a fundamental frequency f and a specified amount of its second harmonic 2f. The advantages and limitations of this method were evaluated with both acoustic measurements of harmonic generation and theoretical simulations based on the KZK equation. The use of two frequencies in a pulse results in the generation of the sum and difference frequency components in addition to the other harmonic components. While with single frequency pulses, only power modulation and power modulated pulse inversion contained odd harmonic components, with the dual frequency pulse, pulse inversion now also contains odd harmonic components.

  16. BEAMS3D Neutral Beam Injection Model

    SciTech Connect

    Lazerson, Samuel

    2014-04-14

    With the advent of applied 3D fi elds in Tokamaks and modern high performance stellarators, a need has arisen to address non-axisymmetric effects on neutral beam heating and fueling. We report on the development of a fully 3D neutral beam injection (NBI) model, BEAMS3D, which addresses this need by coupling 3D equilibria to a guiding center code capable of modeling neutral and charged particle trajectories across the separatrix and into the plasma core. Ionization, neutralization, charge-exchange, viscous velocity reduction, and pitch angle scattering are modeled with the ADAS atomic physics database [1]. Benchmark calculations are presented to validate the collisionless particle orbits, neutral beam injection model, frictional drag, and pitch angle scattering effects. A calculation of neutral beam heating in the NCSX device is performed, highlighting the capability of the code to handle 3D magnetic fields.

  17. Fabrication of 3D Silicon Sensors

    SciTech Connect

    Kok, A.; Hansen, T.E.; Hansen, T.A.; Lietaer, N.; Summanwar, A.; Kenney, C.; Hasi, J.; Da Via, C.; Parker, S.I.; /Hawaii U.

    2012-06-06

    Silicon sensors with a three-dimensional (3-D) architecture, in which the n and p electrodes penetrate through the entire substrate, have many advantages over planar silicon sensors including radiation hardness, fast time response, active edge and dual readout capabilities. The fabrication of 3D sensors is however rather complex. In recent years, there have been worldwide activities on 3D fabrication. SINTEF in collaboration with Stanford Nanofabrication Facility have successfully fabricated the original (single sided double column type) 3D detectors in two prototype runs and the third run is now on-going. This paper reports the status of this fabrication work and the resulted yield. The work of other groups such as the development of double sided 3D detectors is also briefly reported.

  18. 2D/3D switchable displays

    NASA Astrophysics Data System (ADS)

    Dekker, T.; de Zwart, S. T.; Willemsen, O. H.; Hiddink, M. G. H.; IJzerman, W. L.

    2006-02-01

    A prerequisite for a wide market acceptance of 3D displays is the ability to switch between 3D and full resolution 2D. In this paper we present a robust and cost effective concept for an auto-stereoscopic switchable 2D/3D display. The display is based on an LCD panel, equipped with switchable LC-filled lenticular lenses. We will discuss 3D image quality, with the focus on display uniformity. We show that slanting the lenticulars in combination with a good lens design can minimize non-uniformities in our 20" 2D/3D monitors. Furthermore, we introduce fractional viewing systems as a very robust concept to further improve uniformity in the case slanting the lenticulars and optimizing the lens design are not sufficient. We will discuss measurements and numerical simulations of the key optical characteristics of this display. Finally, we discuss 2D image quality, the switching characteristics and the residual lens effect.

  19. 6D Interpretation of 3D Gravity

    NASA Astrophysics Data System (ADS)

    Herfray, Yannick; Krasnov, Kirill; Scarinci, Carlos

    2017-02-01

    We show that 3D gravity, in its pure connection formulation, admits a natural 6D interpretation. The 3D field equations for the connection are equivalent to 6D Hitchin equations for the Chern–Simons 3-form in the total space of the principal bundle over the 3-dimensional base. Turning this construction around one gets an explanation of why the pure connection formulation of 3D gravity exists. More generally, we interpret 3D gravity as the dimensional reduction of the 6D Hitchin theory. To this end, we show that any \\text{SU}(2) invariant closed 3-form in the total space of the principal \\text{SU}(2) bundle can be parametrised by a connection together with a 2-form field on the base. The dimensional reduction of the 6D Hitchin theory then gives rise to 3D gravity coupled to a topological 2-form field.

  20. Biocompatible 3D Matrix with Antimicrobial Properties.

    PubMed

    Ion, Alberto; Andronescu, Ecaterina; Rădulescu, Dragoș; Rădulescu, Marius; Iordache, Florin; Vasile, Bogdan Ștefan; Surdu, Adrian Vasile; Albu, Madalina Georgiana; Maniu, Horia; Chifiriuc, Mariana Carmen; Grumezescu, Alexandru Mihai; Holban, Alina Maria

    2016-01-20

    The aim of this study was to develop, characterize and assess the biological activity of a new regenerative 3D matrix with antimicrobial properties, based on collagen (COLL), hydroxyapatite (HAp), β-cyclodextrin (β-CD) and usnic acid (UA). The prepared 3D matrix was characterized by Scanning Electron Microscopy (SEM), Fourier Transform Infrared Microscopy (FT-IRM), Transmission Electron Microscopy (TEM), and X-ray Diffraction (XRD). In vitro qualitative and quantitative analyses performed on cultured diploid cells demonstrated that the 3D matrix is biocompatible, allowing the normal development and growth of MG-63 osteoblast-like cells and exhibited an antimicrobial effect, especially on the Staphylococcus aureus strain, explained by the particular higher inhibitory activity of usnic acid (UA) against Gram positive bacterial strains. Our data strongly recommend the obtained 3D matrix to be used as a successful alternative for the fabrication of three dimensional (3D) anti-infective regeneration matrix for bone tissue engineering.

  1. Quon 3D language for quantum information

    PubMed Central

    Liu, Zhengwei; Wozniakowski, Alex; Jaffe, Arthur M.

    2017-01-01

    We present a 3D topological picture-language for quantum information. Our approach combines charged excitations carried by strings, with topological properties that arise from embedding the strings in the interior of a 3D manifold with boundary. A quon is a composite that acts as a particle. Specifically, a quon is a hemisphere containing a neutral pair of open strings with opposite charge. We interpret multiquons and their transformations in a natural way. We obtain a type of relation, a string–genus “joint relation,” involving both a string and the 3D manifold. We use the joint relation to obtain a topological interpretation of the C∗-Hopf algebra relations, which are widely used in tensor networks. We obtain a 3D representation of the controlled NOT (CNOT) gate that is considerably simpler than earlier work, and a 3D topological protocol for teleportation. PMID:28167790

  2. 3-D Visualizations At (Almost) No Expense

    NASA Astrophysics Data System (ADS)

    Sedlock, R. L.

    2003-12-01

    Like most teaching-oriented public universities, San José State University (part of the California State University system) currently faces severe budgetary constraints. These circumstances prohibit the construction of one or more Geo-Walls on-campus. Nevertheless, the Department of Geology has pursued alternatives that enable our students to benefit from 3-D visualizations such as those used with the Geo-Wall. This experience - a sort of virtual virtuality - depends only on the availability of a computer lab and an optional plotter. Starting in June 2003, we have used the methods described here with two diverse groups of participants: middle- and high-school teachers taking professional development workshops through grants funded by NSF and NASA, and regular university students enrolled in introductory earth science and geology laboratory courses. We use two types of three-dimensional images with our students: visualizations from the on-line Gallery of Virtual Topography (Steve Reynolds), and USGS digital topographic quadrangles that have been transformed into anaglyph files for viewing with 3-D glasses. The procedure for transforming DEMs into these anaglyph files, developed by Paul Morin, is available at http://geosun.sjsu.edu/~sedlock/anaglyph.html. The resulting images can be used with students in one of two ways. First, maps can be printed on a suitable plotter, laminated (optional but preferable), and used repeatedly with different classes. Second, the images can be viewed in school computer labs or by students on their own computers. Chief advantages of the plotter option are (1) full-size maps (single or tiled) viewable in their entirety, and (2) dependability (independent of Internet connections and electrical power). Chief advantages of the computer option are (1) minimal preparation time and no other needed resources, assuming a computer lab with Internet access, and (2) students can work with the images outside of regularly scheduled courses. Both

  3. 3D Visualization Development of SIUE Campus

    NASA Astrophysics Data System (ADS)

    Nellutla, Shravya

    Geographic Information Systems (GIS) has progressed from the traditional map-making to the modern technology where the information can be created, edited, managed and analyzed. Like any other models, maps are simplified representations of real world. Hence visualization plays an essential role in the applications of GIS. The use of sophisticated visualization tools and methods, especially three dimensional (3D) modeling, has been rising considerably due to the advancement of technology. There are currently many off-the-shelf technologies available in the market to build 3D GIS models. One of the objectives of this research was to examine the available ArcGIS and its extensions for 3D modeling and visualization and use them to depict a real world scenario. Furthermore, with the advent of the web, a platform for accessing and sharing spatial information on the Internet, it is possible to generate interactive online maps. Integrating Internet capacity with GIS functionality redefines the process of sharing and processing the spatial information. Enabling a 3D map online requires off-the-shelf GIS software, 3D model builders, web server, web applications and client server technologies. Such environments are either complicated or expensive because of the amount of hardware and software involved. Therefore, the second objective of this research was to investigate and develop simpler yet cost-effective 3D modeling approach that uses available ArcGIS suite products and the free 3D computer graphics software for designing 3D world scenes. Both ArcGIS Explorer and ArcGIS Online will be used to demonstrate the way of sharing and distributing 3D geographic information on the Internet. A case study of the development of 3D campus for the Southern Illinois University Edwardsville is demonstrated.

  4. Pathways for Learning from 3D Technology

    PubMed Central

    Carrier, L. Mark; Rab, Saira S.; Rosen, Larry D.; Vasquez, Ludivina; Cheever, Nancy A.

    2016-01-01

    The purpose of this study was to find out if 3D stereoscopic presentation of information in a movie format changes a viewer's experience of the movie content. Four possible pathways from 3D presentation to memory and learning were considered: a direct connection based on cognitive neuroscience research; a connection through "immersion" in that 3D presentations could provide additional sensorial cues (e.g., depth cues) that lead to a higher sense of being surrounded by the stimulus; a connection through general interest such that 3D presentation increases a viewer’s interest that leads to greater attention paid to the stimulus (e.g., "involvement"); and a connection through discomfort, with the 3D goggles causing discomfort that interferes with involvement and thus with memory. The memories of 396 participants who viewed two-dimensional (2D) or 3D movies at movie theaters in Southern California were tested. Within three days of viewing a movie, participants filled out an online anonymous questionnaire that queried them about their movie content memories, subjective movie-going experiences (including emotional reactions and "presence") and demographic backgrounds. The responses to the questionnaire were subjected to path analyses in which several different links between 3D presentation to memory (and other variables) were explored. The results showed there were no effects of 3D presentation, either directly or indirectly, upon memory. However, the largest effects of 3D presentation were on emotions and immersion, with 3D presentation leading to reduced positive emotions, increased negative emotions and lowered immersion, compared to 2D presentations. PMID:28078331

  5. The 3D widgets for exploratory scientific visualization

    NASA Technical Reports Server (NTRS)

    Herndon, Kenneth P.; Meyer, Tom

    1995-01-01

    Computational fluid dynamics (CFD) techniques are used to simulate flows of fluids like air or water around such objects as airplanes and automobiles. These techniques usually generate very large amounts of numerical data which are difficult to understand without using graphical scientific visualization techniques. There are a number of commercial scientific visualization applications available today which allow scientists to control visualization tools via textual and/or 2D user interfaces. However, these user interfaces are often difficult to use. We believe that 3D direct-manipulation techniques for interactively controlling visualization tools will provide opportunities for powerful and useful interfaces with which scientists can more effectively explore their datasets. A few systems have been developed which use these techniques. In this paper, we will present a variety of 3D interaction techniques for manipulating parameters of visualization tools used to explore CFD datasets, and discuss in detail various techniques for positioning tools in a 3D scene.

  6. Phonon-drag thermopower in 3D Dirac semimetals.

    PubMed

    Kubakaddi, S S

    2015-11-18

    A theory of low-temperature phonon-drag thermopower S(g) in three-dimensional (3D) Dirac semimetals has been developed considering screened electron-phonon deformation potential coupling. Numerical investigations of S(g), in the boundary scattering regime for phonons, are made in 3D Dirac semimetal Cd3As2, as a function of temperature T and electron concentration n e. S(g) is found to increase rapidly for about T  <  1 K and nearly levels off for higher T. It is also seen that S(g) increases (decreases) with decreasing n e at lower (higher) T (<2 K). A screening effect is found to be very significant, strongly affecting T and n e dependence for about  <1 K and becoming negligible at higher temperature. In the Bloch-Gruneisen (BG) regime the power laws S(g) ~ T(8) (T(4)) and S(g) ~ n(e)(-5/3)(n(e)(-1/3) with (without) screening are obtained. These laws with respect to T and n e are, respectively, characteristics of 3D phonons and Dirac 3D electrons. Comparison with diffusion thermopower S(d) shows that S (g) dominates (and is much greater than) S(d) for about T  >  0.2 K. Herring's law S(g) μ p ~ T (-1), relating phonon limited mobility μ p and S(g) in the BG regime, is shown to be valid in 3D Dirac semimetals. The results obtained here are compared with those in 3D semiconductors, low-dimensional semiconductor heterojunctions and graphene. We conclude that n e-dependent measurements, rather than T-dependent ones, provide a clearer signature of the 3D Dirac semimetal phase.

  7. Phonon-drag thermopower in 3D Dirac semimetals

    NASA Astrophysics Data System (ADS)

    Kubakaddi, S. S.

    2015-11-01

    A theory of low-temperature phonon-drag thermopower S g in three-dimensional (3D) Dirac semimetals has been developed considering screened electron-phonon deformation potential coupling. Numerical investigations of S g, in the boundary scattering regime for phonons, are made in 3D Dirac semimetal Cd3As2, as a function of temperature T and electron concentration n e. S g is found to increase rapidly for about T  <  1 K and nearly levels off for higher T. It is also seen that S g increases (decreases) with decreasing n e at lower (higher) T (<2 K). A screening effect is found to be very significant, strongly affecting T and n e dependence for about  <1 K and becoming negligible at higher temperature. In the Bloch-Gruneisen (BG) regime the power laws S g ~ T 8 (T 4) and S g ~ n\\text{e}-5/3 (n\\text{e}-1/3) with (without) screening are obtained. These laws with respect to T and n e are, respectively, characteristics of 3D phonons and Dirac 3D electrons. Comparison with diffusion thermopower S d shows that S g dominates (and is much greater than) S d for about T  >  0.2 K. Herring’s law S g μ p ~ T -1, relating phonon limited mobility μ p and S g in the BG regime, is shown to be valid in 3D Dirac semimetals. The results obtained here are compared with those in 3D semiconductors, low-dimensional semiconductor heterojunctions and graphene. We conclude that n e-dependent measurements, rather than T-dependent ones, provide a clearer signature of the 3D Dirac semimetal phase.

  8. Practical pseudo-3D registration for large tomographic images

    NASA Astrophysics Data System (ADS)

    Liu, Xuan; Laperre, Kjell; Sasov, Alexander

    2014-09-01

    Image registration is a powerful tool in various tomographic applications. Our main focus is on microCT applications in which samples/animals can be scanned multiple times under different conditions or at different time points. For this purpose, a registration tool capable of handling fairly large volumes has been developed, using a novel pseudo-3D method to achieve fast and interactive registration with simultaneous 3D visualization. To reduce computation complexity in 3D registration, we decompose it into several 2D registrations, which are applied to the orthogonal views (transaxial, sagittal and coronal) sequentially and iteratively. After registration in each view, the next view is retrieved with the new transformation matrix for registration. This reduces the computation complexity significantly. For rigid transform, we only need to search for 3 parameters (2 shifts, 1 rotation) in each of the 3 orthogonal views instead of 6 (3 shifts, 3 rotations) for full 3D volume. In addition, the amount of voxels involved is also significantly reduced. For the proposed pseudo-3D method, image-based registration is employed, with Sum of Square Difference (SSD) as the similarity measure. The searching engine is Powell's conjugate direction method. In this paper, only rigid transform is used. However, it can be extended to affine transform by adding scaling and possibly shearing to the transform model. We have noticed that more information can be used in the 2D registration if Maximum Intensity Projections (MIP) or Parallel Projections (PP) is used instead of the orthogonal views. Also, other similarity measures, such as covariance or mutual information, can be easily incorporated. The initial evaluation on microCT data shows very promising results. Two application examples are shown: dental samples before and after treatment and structural changes in materials before and after compression. Evaluation on registration accuracy between pseudo-3D method and true 3D method has

  9. 3D Geological modelling - towards a European level infrastructure

    NASA Astrophysics Data System (ADS)

    Lee, Kathryn A.; van der Krogt, Rob; Busschers, Freek S.

    2013-04-01

    differences in quality and scales with regard to 3D geological modelling in different European countries and regions, within a harmonized European framework? • How to handle the differences in model concepts and perceptions, especially with regard to the leading developers of 3D geological models within Europe? • How to handle differences between participating countries concerning relevant legal issues, governance, and funding models? With a primary focus on these issues, the EGDI-Scope study will provide a number of possible scenarios for delivery of 3D geological models and information within an integrated European application, including the most relevant technical, legal and organizational consequences.

  10. Highly-stretchable 3D-architected Mechanical Metamaterials

    PubMed Central

    Jiang, Yanhui; Wang, Qiming

    2016-01-01

    Soft materials featuring both 3D free-form architectures and high stretchability are highly desirable for a number of engineering applications ranging from cushion modulators, soft robots to stretchable electronics; however, both the manufacturing and fundamental mechanics are largely elusive. Here, we overcome the manufacturing difficulties and report a class of mechanical metamaterials that not only features 3D free-form lattice architectures but also poses ultrahigh reversible stretchability (strain > 414%), 4 times higher than that of the existing counterparts with the similar complexity of 3D architectures. The microarchitected metamaterials, made of highly stretchable elastomers, are realized through an additive manufacturing technique, projection microstereolithography, and its postprocessing. With the fabricated metamaterials, we reveal their exotic mechanical behaviors: Under large-strain tension, their moduli follow a linear scaling relationship with their densities regardless of architecture types, in sharp contrast to the architecture-dependent modulus power-law of the existing engineering materials; under large-strain compression, they present tunable negative-stiffness that enables ultrahigh energy absorption efficiencies. To harness their extraordinary stretchability and microstructures, we demonstrate that the metamaterials open a number of application avenues in lightweight and flexible structure connectors, ultraefficient dampers, 3D meshed rehabilitation structures and stretchable electronics with designed 3D anisotropic conductivity. PMID:27667638

  11. 3D printing of biomimetic microstructures for cancer cell migration.

    PubMed

    Huang, Tina Qing; Qu, Xin; Liu, Justin; Chen, Shaochen

    2014-02-01

    To understand the physical behavior and migration of cancer cells, a 3D in vitro micro-chip in hydrogel was created using 3D projection printing. The micro-chip has a honeycomb branched structure, aiming to mimic 3D vascular morphology to test, monitor, and analyze differences in the behavior of cancer cells (i.e. HeLa) vs. non-cancerous cell lines (i.e. 10 T1/2). The 3D Projection Printing system can fabricate complex structures in seconds from user-created designs. The fabricated microstructures have three different channel widths of 25, 45, and 120 microns wide to reflect a range of blood vessel diameters. HeLa and 10 T1/2 cells seeded within the micro-chip were then analyzed for morphology and cell migration speed. 10 T1/2 cells exhibited greater changes in morphology due to channel size width than HeLa cells; however, channel width had a limited effect on 10 T1/2 cell migration while HeLa cancer cell migration increased as channel width decreased. This physiologically relevant 3D cancer tissue model has the potential to be a powerful tool for future drug discoveries and cancer migration studies.

  12. Highly-stretchable 3D-architected Mechanical Metamaterials

    NASA Astrophysics Data System (ADS)

    Jiang, Yanhui; Wang, Qiming

    2016-09-01

    Soft materials featuring both 3D free-form architectures and high stretchability are highly desirable for a number of engineering applications ranging from cushion modulators, soft robots to stretchable electronics; however, both the manufacturing and fundamental mechanics are largely elusive. Here, we overcome the manufacturing difficulties and report a class of mechanical metamaterials that not only features 3D free-form lattice architectures but also poses ultrahigh reversible stretchability (strain > 414%), 4 times higher than that of the existing counterparts with the similar complexity of 3D architectures. The microarchitected metamaterials, made of highly stretchable elastomers, are realized through an additive manufacturing technique, projection microstereolithography, and its postprocessing. With the fabricated metamaterials, we reveal their exotic mechanical behaviors: Under large-strain tension, their moduli follow a linear scaling relationship with their densities regardless of architecture types, in sharp contrast to the architecture-dependent modulus power-law of the existing engineering materials; under large-strain compression, they present tunable negative-stiffness that enables ultrahigh energy absorption efficiencies. To harness their extraordinary stretchability and microstructures, we demonstrate that the metamaterials open a number of application avenues in lightweight and flexible structure connectors, ultraefficient dampers, 3D meshed rehabilitation structures and stretchable electronics with designed 3D anisotropic conductivity.

  13. 3D printing of biomimetic microstructures for cancer cell migration

    PubMed Central

    Huang, Tina Qing; Qu, Xin; Liu, Justin; Chen, Shaochen

    2013-01-01

    To understand the physical behavior and migration of cancer cells, a 3D in vitro micro-chip in hydrogel was created using 3D projection printing. The micro-chip has a honeycomb branched structure, aiming to mimic 3D vascular morphology to test, monitor, and analyze differences in the behavior of cancer cells (i.e. HeLa) vs. non-cancerous cell lines (i.e. 10T1/2). The 3D Projection Printing system can fabricate complex structures in seconds from user-created designs. The fabricated microstructures have three different channel widths of 25, 45, and 120 microns wide to reflect a range of blood vessel diameters. HeLa and 10T1/2 cells seeded within the micro-chip were then analyzed for morphology and cell migration speed. 10T1/2 cells exhibited greater changes in morphology due to channel size width than HeLa cells; however, channel width had a limited effect on 10T1/2 cell migration while HeLa cancer cell migration increased as channel width decreased. This physiologically relevant 3D cancer tissue model has the potential to be a powerful tool for future drug discoveries and cancer migration studies PMID:24150602

  14. 3-D Mixed Mode Delamination Fracture Criteria - An Experimentalist's Perspective

    NASA Technical Reports Server (NTRS)

    Reeder, James R.

    2006-01-01

    Many delamination failure criteria based on fracture toughness have been suggested over the past few decades, but most only covered the region containing mode I and mode II components of loading because that is where toughness data existed. With new analysis tools, more 3D analyses are being conducted that capture a mode III component of loading. This has increased the need for a fracture criterion that incorporates mode III loading. The introduction of a pure mode III fracture toughness test has also produced data on which to base a full 3D fracture criterion. In this paper, a new framework for visualizing 3D fracture criteria is introduced. The common 2D power law fracture criterion was evaluated to produce unexpected predictions with the introduction of mode III and did not perform well in the critical high mode I region. Another 2D criterion that has been shown to model a wide range of materials well was used as the basis for a new 3D criterion. The new criterion is based on assumptions that the relationship between mode I and mode III toughness is similar to the relation between mode I and mode II and that a linear interpolation can be used between mode II and mode III. Until mixed-mode data exists with a mode III component of loading, 3D fracture criteria cannot be properly evaluated, but these assumptions seem reasonable.

  15. Highly-stretchable 3D-architected Mechanical Metamaterials.

    PubMed

    Jiang, Yanhui; Wang, Qiming

    2016-09-26

    Soft materials featuring both 3D free-form architectures and high stretchability are highly desirable for a number of engineering applications ranging from cushion modulators, soft robots to stretchable electronics; however, both the manufacturing and fundamental mechanics are largely elusive. Here, we overcome the manufacturing difficulties and report a class of mechanical metamaterials that not only features 3D free-form lattice architectures but also poses ultrahigh reversible stretchability (strain > 414%), 4 times higher than that of the existing counterparts with the similar complexity of 3D architectures. The microarchitected metamaterials, made of highly stretchable elastomers, are realized through an additive manufacturing technique, projection microstereolithography, and its postprocessing. With the fabricated metamaterials, we reveal their exotic mechanical behaviors: Under large-strain tension, their moduli follow a linear scaling relationship with their densities regardless of architecture types, in sharp contrast to the architecture-dependent modulus power-law of the existing engineering materials; under large-strain compression, they present tunable negative-stiffness that enables ultrahigh energy absorption efficiencies. To harness their extraordinary stretchability and microstructures, we demonstrate that the metamaterials open a number of application avenues in lightweight and flexible structure connectors, ultraefficient dampers, 3D meshed rehabilitation structures and stretchable electronics with designed 3D anisotropic conductivity.

  16. Dynamical deformations of three-dimensional Lie algebras in Bianchi classification over the harmonic oscillator

    SciTech Connect

    Paal, Eugen; Virkepu, Jueri

    2009-05-15

    Operadic Lax representations for the harmonic oscillator are used to construct the dynamical deformations of three-dimensional (3D) real Lie algebras in the Bianchi classification. It is shown that the energy conservation of the harmonic oscillator is related to the Jacobi identities of the dynamically deformed algebras. Based on this observation, it is proved that the dynamical deformations of 3D real Lie algebras in the Bianchi classification over the harmonic oscillator are Lie algebras.

  17. 3D bioprinting of tissues and organs.

    PubMed

    Murphy, Sean V; Atala, Anthony

    2014-08-01

    Additive manufacturing, otherwise known as three-dimensional (3D) printing, is driving major innovations in many areas, such as engineering, manufacturing, art, education and medicine. Recent advances have enabled 3D printing of biocompatible materials, cells and supporting components into complex 3D functional living tissues. 3D bioprinting is being applied to regenerative medicine to address the need for tissues and organs suitable for transplantation. Compared with non-biological printing, 3D bioprinting involves additional complexities, such as the choice of materials, cell types, growth and differentiation factors, and technical challenges related to the sensitivities of living cells and the construction of tissues. Addressing these complexities requires the integration of technologies from the fields of engineering, biomaterials science, cell biology, physics and medicine. 3D bioprinting has already been used for the generation and transplantation of several tissues, including multilayered skin, bone, vascular grafts, tracheal splints, heart tissue and cartilaginous structures. Other applications include developing high-throughput 3D-bioprinted tissue models for research, drug discovery and toxicology.

  18. Medical 3D Printing for the Radiologist.

    PubMed

    Mitsouras, Dimitris; Liacouras, Peter; Imanzadeh, Amir; Giannopoulos, Andreas A; Cai, Tianrun; Kumamaru, Kanako K; George, Elizabeth; Wake, Nicole; Caterson, Edward J; Pomahac, Bohdan; Ho, Vincent B; Grant, Gerald T; Rybicki, Frank J

    2015-01-01

    While use of advanced visualization in radiology is instrumental in diagnosis and communication with referring clinicians, there is an unmet need to render Digital Imaging and Communications in Medicine (DICOM) images as three-dimensional (3D) printed models capable of providing both tactile feedback and tangible depth information about anatomic and pathologic states. Three-dimensional printed models, already entrenched in the nonmedical sciences, are rapidly being embraced in medicine as well as in the lay community. Incorporating 3D printing from images generated and interpreted by radiologists presents particular challenges, including training, materials and equipment, and guidelines. The overall costs of a 3D printing laboratory must be balanced by the clinical benefits. It is expected that the number of 3D-printed models generated from DICOM images for planning interventions and fabricating implants will grow exponentially. Radiologists should at a minimum be familiar with 3D printing as it relates to their field, including types of 3D printing technologies and materials used to create 3D-printed anatomic models, published applications of models to date, and clinical benefits in radiology. Online supplemental material is available for this article.

  19. Medical 3D Printing for the Radiologist

    PubMed Central

    Mitsouras, Dimitris; Liacouras, Peter; Imanzadeh, Amir; Giannopoulos, Andreas A.; Cai, Tianrun; Kumamaru, Kanako K.; George, Elizabeth; Wake, Nicole; Caterson, Edward J.; Pomahac, Bohdan; Ho, Vincent B.; Grant, Gerald T.

    2015-01-01

    While use of advanced visualization in radiology is instrumental in diagnosis and communication with referring clinicians, there is an unmet need to render Digital Imaging and Communications in Medicine (DICOM) images as three-dimensional (3D) printed models capable of providing both tactile feedback and tangible depth information about anatomic and pathologic states. Three-dimensional printed models, already entrenched in the nonmedical sciences, are rapidly being embraced in medicine as well as in the lay community. Incorporating 3D printing from images generated and interpreted by radiologists presents particular challenges, including training, materials and equipment, and guidelines. The overall costs of a 3D printing laboratory must be balanced by the clinical benefits. It is expected that the number of 3D-printed models generated from DICOM images for planning interventions and fabricating implants will grow exponentially. Radiologists should at a minimum be familiar with 3D printing as it relates to their field, including types of 3D printing technologies and materials used to create 3D-printed anatomic models, published applications of models to date, and clinical benefits in radiology. Online supplemental material is available for this article. ©RSNA, 2015 PMID:26562233

  20. 3D imaging in forensic odontology.

    PubMed

    Evans, Sam; Jones, Carl; Plassmann, Peter

    2010-06-16

    This paper describes the investigation of a new 3D capture method for acquiring and subsequent forensic analysis of bite mark injuries on human skin. When documenting bite marks with standard 2D cameras errors in photographic technique can occur if best practice is not followed. Subsequent forensic analysis of the mark is problematic when a 3D structure is recorded into a 2D space. Although strict guidelines (BAFO) exist, these are time-consuming to follow and, due to their complexity, may produce errors. A 3D image capture and processing system might avoid the problems resulting from the 2D reduction process, simplifying the guidelines and reducing errors. Proposed Solution: a series of experiments are described in this paper to demonstrate that the potential of a 3D system might produce suitable results. The experiments tested precision and accuracy of the traditional 2D and 3D methods. A 3D image capture device minimises the amount of angular distortion, therefore such a system has the potential to create more robust forensic evidence for use in courts. A first set of experiments tested and demonstrated which method of forensic analysis creates the least amount of intra-operator error. A second set tested and demonstrated which method of image capture creates the least amount of inter-operator error and visual distortion. In a third set the effects of angular distortion on 2D and 3D methods of image capture were evaluated.

  1. NUBEAM developments and 3d halo modeling

    NASA Astrophysics Data System (ADS)

    Gorelenkova, M. V.; Medley, S. S.; Kaye, S. M.

    2012-10-01

    Recent developments related to the 3D halo model in NUBEAM code are described. To have a reliable halo neutral source for diagnostic simulation, the TRANSP/NUBEAM code has been enhanced with full implementation of ADAS atomic physic ground state and excited state data for hydrogenic beams and mixed species plasma targets. The ADAS codes and database provide the density and temperature dependence of the atomic data, and the collective nature of the state excitation process. To be able to populate 3D halo output with sufficient statistical resolution, the capability to control the statistics of fast ion CX modeling and for thermal halo launch has been added to NUBEAM. The 3D halo neutral model is based on modification and extension of the ``beam in box'' aligned 3d Cartesian grid that includes the neutral beam itself, 3D fast neutral densities due to CX of partially slowed down fast ions in the beam halo region, 3D thermal neutral densities due to CX deposition and fast neutral recapture source. More details on the 3D halo simulation design will be presented.

  2. Radial 3D-Needlets on the Unit Ball

    NASA Astrophysics Data System (ADS)

    Durastanti, Claudio; Fantaye, Yabebal T.; Hansen, Frode K.; Marinucci, Domenico; Pesenson, Isaac Z.

    2014-05-01

    We present a simple construction of spherical wavelets for the unit ball, which we label Radial 3D Needlets. We envisage an experimental framework where data are collected on concentric spheres with the same pixelization at different radial distances from the origin. The unit ball is hence viewed as a tensor product of the unit interval with the unit sphere: a set of eigenfunctions is therefore defined on the corresponding Laplacian operator. Wavelets are then constructed by a smooth convolution of the projectors defined by these eigenfunctions. Localization properties may be rigorously shown to hold in the real and harmonic domain, and an exact reconstruction formula holds; the system allows a very convenient computational implementation.

  3. 3D packaging for integrated circuit systems

    SciTech Connect

    Chu, D.; Palmer, D.W.

    1996-11-01

    A goal was set for high density, high performance microelectronics pursued through a dense 3D packing of integrated circuits. A {open_quotes}tool set{close_quotes} of assembly processes have been developed that enable 3D system designs: 3D thermal analysis, silicon electrical through vias, IC thinning, mounting wells in silicon, adhesives for silicon stacking, pretesting of IC chips before commitment to stacks, and bond pad bumping. Validation of these process developments occurred through both Sandia prototypes and subsequent commercial examples.

  4. FUN3D Manual: 12.5

    NASA Technical Reports Server (NTRS)

    Biedron, Robert T.; Derlaga, Joseph M.; Gnoffo, Peter A.; Hammond, Dana P.; Jones, William T.; Kleb, William L.; Lee-Rausch, Elizabeth M.; Nielsen, Eric J.; Park, Michael A.; Rumsey, Christopher L.; Thomas, James L.; Wood, William A.

    2014-01-01

    This manual describes the installation and execution of FUN3D version 12.5, including optional dependent packages. FUN3D is a suite of computational uid dynamics simulation and design tools that uses mixed-element unstructured grids in a large number of formats, including structured multiblock and overset grid systems. A discretely-exact adjoint solver enables ecient gradient-based design and grid adaptation to reduce estimated discretization error. FUN3D is available with and without a reacting, real-gas capability. This generic gas option is available only for those persons that qualify for its beta release status.

  5. FUN3D Manual: 12.4

    NASA Technical Reports Server (NTRS)

    Biedron, Robert T.; Derlaga, Joseph M.; Gnoffo, Peter A.; Hammond, Dana P.; Jones, William T.; Kleb, Bil; Lee-Rausch, Elizabeth M.; Nielsen, Eric J.; Park, Michael A.; Rumsey, Christopher L.; Thomas, James L.; Wood, William A.

    2014-01-01

    This manual describes the installation and execution of FUN3D version 12.4, including optional dependent packages. FUN3D is a suite of computational fluid dynamics simulation and design tools that uses mixedelement unstructured grids in a large number of formats, including structured multiblock and overset grid systems. A discretely-exact adjoint solver enables efficient gradient-based design and grid adaptation to reduce estimated discretization error. FUN3D is available with and without a reacting, real-gas capability. This generic gas option is available only for those persons that qualify for its beta release status.

  6. 3D Immersive Visualization with Astrophysical Data

    NASA Astrophysics Data System (ADS)

    Kent, Brian R.

    2017-01-01

    We present the refinement of a new 3D immersion technique for astrophysical data visualization.Methodology to create 360 degree spherical panoramas is reviewed. The 3D software package Blender coupled with Python and the Google Spatial Media module are used together to create the final data products. Data can be viewed interactively with a mobile phone or tablet or in a web browser. The technique can apply to different kinds of astronomical data including 3D stellar and galaxy catalogs, images, and planetary maps.

  7. A high capacity 3D steganography algorithm.

    PubMed

    Chao, Min-Wen; Lin, Chao-hung; Yu, Cheng-Wei; Lee, Tong-Yee

    2009-01-01

    In this paper, we present a very high-capacity and low-distortion 3D steganography scheme. Our steganography approach is based on a novel multilayered embedding scheme to hide secret messages in the vertices of 3D polygon models. Experimental results show that the cover model distortion is very small as the number of hiding layers ranges from 7 to 13 layers. To the best of our knowledge, this novel approach can provide much higher hiding capacity than other state-of-the-art approaches, while obeying the low distortion and security basic requirements for steganography on 3D models.

  8. How We 3D-Print Aerogel

    SciTech Connect

    2015-04-23

    A new type of graphene aerogel will make for better energy storage, sensors, nanoelectronics, catalysis and separations. Lawrence Livermore National Laboratory researchers have made graphene aerogel microlattices with an engineered architecture via a 3D printing technique known as direct ink writing. The research appears in the April 22 edition of the journal, Nature Communications. The 3D printed graphene aerogels have high surface area, excellent electrical conductivity, are lightweight, have mechanical stiffness and exhibit supercompressibility (up to 90 percent compressive strain). In addition, the 3D printed graphene aerogel microlattices show an order of magnitude improvement over bulk graphene materials and much better mass transport.

  9. FUN3D Manual: 12.6

    NASA Technical Reports Server (NTRS)

    Biedron, Robert T.; Derlaga, Joseph M.; Gnoffo, Peter A.; Hammond, Dana P.; Jones, William T.; Kleb, William L.; Lee-Rausch, Elizabeth M.; Nielsen, Eric J.; Park, Michael A.; Rumsey, Christopher L.; Thomas, James L.; Wood, William A.

    2015-01-01

    This manual describes the installation and execution of FUN3D version 12.6, including optional dependent packages. FUN3D is a suite of computational fluid dynamics simulation and design tools that uses mixed-element unstructured grids in a large number of formats, including structured multiblock and overset grid systems. A discretely-exact adjoint solver enables efficient gradient-based design and grid adaptation to reduce estimated discretization error. FUN3D is available with and without a reacting, real-gas capability. This generic gas option is available only for those persons that qualify for its beta release status.

  10. FUN3D Manual: 12.9

    NASA Technical Reports Server (NTRS)

    Biedron, Robert T.; Carlson, Jan-Renee; Derlaga, Joseph M.; Gnoffo, Peter A.; Hammond, Dana P.; Jones, William T.; Kleb, Bil; Lee-Rausch, Elizabeth M.; Nielsen, Eric J.; Park, Michael A.; Rumsey, Christopher L.; Thomas, James L.; Wood, William A.

    2016-01-01

    This manual describes the installation and execution of FUN3D version 12.9, including optional dependent packages. FUN3D is a suite of computational fluid dynamics simulation and design tools that uses mixed-element unstructured grids in a large number of formats, including structured multiblock and overset grid systems. A discretely-exact adjoint solver enables efficient gradient-based design and grid adaptation to reduce estimated discretization error. FUN3D is available with and without a reacting, real-gas capability. This generic gas option is available only for those persons that qualify for its beta release status.

  11. FUN3D Manual: 13.1

    NASA Technical Reports Server (NTRS)

    Biedron, Robert T.; Carlson, Jan-Renee; Derlaga, Joseph M.; Gnoffo, Peter A.; Hammond, Dana P.; Jones, William T.; Kleb, Bil; Lee-Rausch, Elizabeth M.; Nielsen, Eric J.; Park, Michael A.; Rumsey, Christopher L.; Thomas, James L.; Wood, William A.

    2017-01-01

    This manual describes the installation and execution of FUN3D version 13.1, including optional dependent packages. FUN3D is a suite of computational fluid dynamics simulation and design tools that uses mixed-element unstructured grids in a large number of formats, including structured multiblock and overset grid systems. A discretely-exact adjoint solver enables efficient gradient-based design and grid adaptation to reduce estimated discretization error. FUN3D is available with and without a reacting, real-gas capability. This generic gas option is available only for those persons that qualify for its beta release status.

  12. FUN3D Manual: 12.7

    NASA Technical Reports Server (NTRS)

    Biedron, Robert T.; Carlson, Jan-Renee; Derlaga, Joseph M.; Gnoffo, Peter A.; Hammond, Dana P.; Jones, William T.; Kleb, Bil; Lee-Rausch, Elizabeth M.; Nielsen, Eric J.; Park, Michael A.; Rumsey, Christopher L.; Thomas, James L.; Wood, William A.

    2015-01-01

    This manual describes the installation and execution of FUN3D version 12.7, including optional dependent packages. FUN3D is a suite of computational fluid dynamics simulation and design tools that uses mixed-element unstructured grids in a large number of formats, including structured multiblock and overset grid systems. A discretely-exact adjoint solver enables efficient gradient-based design and grid adaptation to reduce estimated discretization error. FUN3D is available with and without a reacting, real-gas capability. This generic gas option is available only for those persons that qualify for its beta release status.

  13. FUN3D Manual: 13.0

    NASA Technical Reports Server (NTRS)

    Biedron, Robert T.; Carlson, Jan-Renee; Derlaga, Joseph M.; Gnoffo, Peter A.; Hammond, Dana P.; Jones, William T.; Kleb, Bill; Lee-Rausch, Elizabeth M.; Nielsen, Eric J.; Park, Michael A.; Rumsey, Christopher L.; Thomas, James L.; Wood, William A.

    2016-01-01

    This manual describes the installation and execution of FUN3D version 13.0, including optional dependent packages. FUN3D is a suite of computational fluid dynamics simulation and design tools that uses mixed-element unstructured grids in a large number of formats, including structured multiblock and overset grid systems. A discretely-exact adjoint solver enables efficient gradient-based design and grid adaptation to reduce estimated discretization error. FUN3D is available with and without a reacting, real-gas capability. This generic gas option is available only for those persons that qualify for its beta release status.

  14. FUN3D Manual: 12.8

    NASA Technical Reports Server (NTRS)

    Biedron, Robert T.; Carlson, Jan-Renee; Derlaga, Joseph M.; Gnoffo, Peter A.; Hammond, Dana P.; Jones, William T.; Kleb, Bil; Lee-Rausch, Elizabeth M.; Nielsen, Eric J.; Park, Michael A.; Rumsey, Christopher L.; Thomas, James L.; Wood, William A.

    2015-01-01

    This manual describes the installation and execution of FUN3D version 12.8, including optional dependent packages. FUN3D is a suite of computational fluid dynamics simulation and design tools that uses mixed-element unstructured grids in a large number of formats, including structured multiblock and overset grid systems. A discretely-exact adjoint solver enables efficient gradient-based design and grid adaptation to reduce estimated discretization error. FUN3D is available with and without a reacting, real-gas capability. This generic gas option is available only for those persons that qualify for its beta release status.

  15. RHOCUBE: 3D density distributions modeling code

    NASA Astrophysics Data System (ADS)

    Nikutta, Robert; Agliozzo, Claudia

    2016-11-01

    RHOCUBE models 3D density distributions on a discrete Cartesian grid and their integrated 2D maps. It can be used for a range of applications, including modeling the electron number density in LBV shells and computing the emission measure. The RHOCUBE Python package provides several 3D density distributions, including a powerlaw shell, truncated Gaussian shell, constant-density torus, dual cones, and spiralling helical tubes, and can accept additional distributions. RHOCUBE provides convenient methods for shifts and rotations in 3D, and if necessary, an arbitrary number of density distributions can be combined into the same model cube and the integration ∫ dz performed through the joint density field.

  16. Explicit 3-D Hydrodynamic FEM Program

    SciTech Connect

    2000-11-07

    DYNA3D is a nonlinear explicit finite element code for analyzing 3-D structures and solid continuum. The code is vectorized and available on several computer platforms. The element library includes continuum, shell, beam, truss and spring/damper elements to allow maximum flexibility in modeling physical problems. Many materials are available to represent a wide range of material behavior, including elasticity, plasticity, composites, thermal effects and rate dependence. In addition, DYNA3D has a sophisticated contact interface capability, including frictional sliding, single surface contact and automatic contact generation.

  17. 3D-HIM: A 3D High-density Interleaved Memory for Bipolar RRAM Design

    DTIC Science & Technology

    2013-05-01

    JOURNAL ARTICLE (Post Print ) 3. DATES COVERED (From - To) DEC 2010 – NOV 2012 4. TITLE AND SUBTITLE 3D -HIM: A 3D HIGH-DENSITY INTERLEAVED MEMORY...emerged as one of the promising candidates for large data storage in computing systems. Moreover, building up RRAM in a three dimensional ( 3D ) stacking...brings in the potential reliability issue. To alleviate the situation, we introduce two novel 3D stacking structures built upon bipolar RRAM

  18. Conformal geometry and its applications on 3D shape matching, recognition, and stitching.

    PubMed

    Wang, Sen; Wang, Yang; Jin, Miao; Gu, Xianfeng David; Samaras, Dimitris

    2007-07-01

    Three-dimensional shape matching is a fundamental issue in computer vision with many applications such as shape registration, 3D object recognition, and classification. However, shape matching with noise, occlusion, and clutter is a challenging problem. In this paper, we analyze a family of quasi-conformal maps including harmonic maps, conformal maps, and least-squares conformal maps with regards to 3D shape matching. As a result, we propose a novel and computationally efficient shape matching framework by using least-squares conformal maps. According to conformal geometry theory, each 3D surface with disk topology can be mapped to a 2D domain through a global optimization and the resulting map is a diffeomorphism, i.e., one-to-one and onto. This allows us to simplify the 3D shape-matching problem to a 2D image-matching problem, by comparing the resulting 2D parametric maps, which are stable, insensitive to resolution changes and robust to occlusion, and noise. Therefore, highly accurate and efficient 3D shape matching algorithms can be achieved by using the above three parametric maps. Finally, the robustness of least-squares conformal maps is evaluated and analyzed comprehensively in 3D shape matching with occlusion, noise, and resolution variation. In order to further demonstrate the performance of our proposed method, we also conduct a series of experiments on two computer vision applications, i.e., 3D face recognition and 3D nonrigid surface alignment and stitching.

  19. Do-It-Yourself: 3D Models of Hydrogenic Orbitals through 3D Printing

    ERIC Educational Resources Information Center

    Griffith, Kaitlyn M.; de Cataldo, Riccardo; Fogarty, Keir H.

    2016-01-01

    Introductory chemistry students often have difficulty visualizing the 3-dimensional shapes of the hydrogenic electron orbitals without the aid of physical 3D models. Unfortunately, commercially available models can be quite expensive. 3D printing offers a solution for producing models of hydrogenic orbitals. 3D printing technology is widely…

  20. XML3D and Xflow: combining declarative 3D for the Web with generic data flows.

    PubMed

    Klein, Felix; Sons, Kristian; Rubinstein, Dmitri; Slusallek, Philipp

    2013-01-01

    Researchers have combined XML3D, which provides declarative, interactive 3D scene descriptions based on HTML5, with Xflow, a language for declarative, high-performance data processing. The result lets Web developers combine a 3D scene graph with data flows for dynamic meshes, animations, image processing, and postprocessing.

  1. Quantifying modes of 3D cell migration

    PubMed Central

    Driscoll, Meghan K.; Danuser, Gaudenz

    2015-01-01

    Although it is widely appreciated that cells migrate in a variety of diverse environments in vivo, we are only now beginning to use experimental workflows that yield images with sufficient spatiotemporal resolution to study the molecular processes governing cell migration in 3D environments. Since cell migration is a dynamic process, it is usually studied via microscopy, but 3D movies of 3D processes are difficult to interpret by visual inspection. In this review, we discuss the technologies required to study the diversity of 3D cell migration modes with a focus on the visualization and computational analysis tools needed to study cell migration quantitatively at a level comparable to the analyses performed today on cells crawling on flat substrates. PMID:26603943

  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. Cyclone Rusty's Landfall in 3-D

    NASA Video Gallery

    This 3-D image derived from NASA's TRMM satellite Precipitation Radar data on February 26, 2013 at 0654 UTC showed that the tops of some towering thunderstorms in Rusty's eye wall were reaching hei...

  4. Tropical Cyclone Jack in Satellite 3-D

    NASA Video Gallery

    This 3-D flyby from NASA's TRMM satellite of Tropical Cyclone Jack on April 21 shows that some of the thunderstorms were shown by TRMM PR were still reaching height of at least 17 km (10.5 miles). ...

  5. Future Engineers 3-D Print Timelapse

    NASA Video Gallery

    NASA Challenges K-12 students to create a model of a container for space using 3-D modeling software. Astronauts need containers of all kinds - from advanced containers that can study fruit flies t...

  6. 3-D Animation of Typhoon Bopha

    NASA Video Gallery

    This 3-D animation of NASA's TRMM satellite data showed Typhoon Bopha tracking over the Philippines on Dec. 3 and moving into the Sulu Sea on Dec. 4, 2012. TRMM saw heavy rain (red) was falling at ...

  7. 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.

  8. Designing Biomaterials for 3D Printing.

    PubMed

    Guvendiren, Murat; Molde, Joseph; Soares, Rosane M D; Kohn, Joachim

    2016-10-10

    Three-dimensional (3D) printing is becoming an increasingly common technique to fabricate scaffolds and devices for tissue engineering applications. This is due to the potential of 3D printing to provide patient-specific designs, high structural complexity, rapid on-demand fabrication at a low-cost. One of the major bottlenecks that limits the widespread acceptance of 3D printing in biomanufacturing is the lack of diversity in "biomaterial inks". Printability of a biomaterial is determined by the printing technique. Although a wide range of biomaterial inks including polymers, ceramics, hydrogels and composites have been developed, the field is still struggling with processing of these materials into self-supporting devices with tunable mechanics, degradation, and bioactivity. This review aims to highlight the past and recent advances in biomaterial ink development and design considerations moving forward. A brief overview of 3D printing technologies focusing on ink design parameters is also included.

  9. 3D Printing for Tissue Engineering.

    PubMed

    Richards, Dylan Jack; Tan, Yu; Jia, Jia; Yao, Hai; Mei, Ying

    2013-10-01

    Tissue engineering aims to fabricate functional tissue for applications in regenerative medicine and drug testing. More recently, 3D printing has shown great promise in tissue fabrication with a structural control from micro- to macro-scale by using a layer-by-layer approach. Whether through scaffold-based or scaffold-free approaches, the standard for 3D printed tissue engineering constructs is to provide a biomimetic structural environment that facilitates tissue formation and promotes host tissue integration (e.g., cellular infiltration, vascularization, and active remodeling). This review will cover several approaches that have advanced the field of 3D printing through novel fabrication methods of tissue engineering constructs. It will also discuss the applications of synthetic and natural materials for 3D printing facilitated tissue fabrication.

  10. 3-D Flyover Visualization of Veil Nebula

    NASA Video Gallery

    This 3-D visualization flies across a small portion of the Veil Nebula as photographed by the Hubble Space Telescope. This region is a small part of a huge expanding remnant from a star that explod...

  11. TRMM 3-D Flyby of Ingrid

    NASA Video Gallery

    This 3-D flyby of Tropical Storm Ingrid's rainfall was created from TRMM satellite data for Sept. 16. Heaviest rainfall appears in red towers over the Gulf of Mexico, while moderate rainfall stretc...

  12. Quantifying Modes of 3D Cell Migration.

    PubMed

    Driscoll, Meghan K; Danuser, Gaudenz

    2015-12-01

    Although it is widely appreciated that cells migrate in a variety of diverse environments in vivo, we are only now beginning to use experimental workflows that yield images with sufficient spatiotemporal resolution to study the molecular processes governing cell migration in 3D environments. Since cell migration is a dynamic process, it is usually studied via microscopy, but 3D movies of 3D processes are difficult to interpret by visual inspection. In this review, we discuss the technologies required to study the diversity of 3D cell migration modes with a focus on the visualization and computational analysis tools needed to study cell migration quantitatively at a level comparable to the analyses performed today on cells crawling on flat substrates.

  13. 3D Printing for Tissue Engineering

    PubMed Central

    Jia, Jia; Yao, Hai; Mei, Ying

    2016-01-01

    Tissue engineering aims to fabricate functional tissue for applications in regenerative medicine and drug testing. More recently, 3D printing has shown great promise in tissue fabrication with a structural control from micro- to macro-scale by using a layer-by-layer approach. Whether through scaffold-based or scaffold-free approaches, the standard for 3D printed tissue engineering constructs is to provide a biomimetic structural environment that facilitates tissue formation and promotes host tissue integration (e.g., cellular infiltration, vascularization, and active remodeling). This review will cover several approaches that have advanced the field of 3D printing through novel fabrication methods of tissue engineering constructs. It will also discuss the applications of synthetic and natural materials for 3D printing facilitated tissue fabrication. PMID:26869728

  14. Eyes on the Earth 3D

    NASA Technical Reports Server (NTRS)

    Kulikov, anton I.; Doronila, Paul R.; Nguyen, Viet T.; Jackson, Randal K.; Greene, William M.; Hussey, Kevin J.; Garcia, Christopher M.; Lopez, Christian A.

    2013-01-01

    Eyes on the Earth 3D software gives scientists, and the general public, a realtime, 3D interactive means of accurately viewing the real-time locations, speed, and values of recently collected data from several of NASA's Earth Observing Satellites using a standard Web browser (climate.nasa.gov/eyes). Anyone with Web access can use this software to see where the NASA fleet of these satellites is now, or where they will be up to a year in the future. The software also displays several Earth Science Data sets that have been collected on a daily basis. This application uses a third-party, 3D, realtime, interactive game engine called Unity 3D to visualize the satellites and is accessible from a Web browser.

  15. Nonlaser-based 3D surface imaging

    SciTech Connect

    Lu, Shin-yee; Johnson, R.K.; Sherwood, R.J.

    1994-11-15

    3D surface imaging refers to methods that generate a 3D surface representation of objects of a scene under viewing. Laser-based 3D surface imaging systems are commonly used in manufacturing, robotics and biomedical research. Although laser-based systems provide satisfactory solutions for most applications, there are situations where non laser-based approaches are preferred. The issues that make alternative methods sometimes more attractive are: (1) real-time data capturing, (2) eye-safety, (3) portability, and (4) work distance. The focus of this presentation is on generating a 3D surface from multiple 2D projected images using CCD cameras, without a laser light source. Two methods are presented: stereo vision and depth-from-focus. Their applications are described.

  16. 3-D TRMM Flyby of Hurricane Amanda

    NASA Video Gallery

    The TRMM satellite flew over Hurricane Amanda on Tuesday, May 27 at 1049 UTC (6:49 a.m. EDT) and captured rainfall rates and cloud height data that was used to create this 3-D simulated flyby. Cred...

  17. 3D-printed bioanalytical devices

    NASA Astrophysics Data System (ADS)

    Bishop, Gregory W.; Satterwhite-Warden, Jennifer E.; Kadimisetty, Karteek; Rusling, James F.

    2016-07-01

    While 3D printing technologies first appeared in the 1980s, prohibitive costs, limited materials, and the relatively small number of commercially available printers confined applications mainly to prototyping for manufacturing purposes. As technologies, printer cost, materials, and accessibility continue to improve, 3D printing has found widespread implementation in research and development in many disciplines due to ease-of-use and relatively fast design-to-object workflow. Several 3D printing techniques have been used to prepare devices such as milli- and microfluidic flow cells for analyses of cells and biomolecules as well as interfaces that enable bioanalytical measurements using cellphones. This review focuses on preparation and applications of 3D-printed bioanalytical devices.

  18. 3D liver surgery simulation: computer-assisted surgical planning with 3D simulation software and 3D printing.

    PubMed

    Oshiro, Yukio; Ohkohchi, Nobuhiro

    2017-03-27

    To perform accurate hepatectomy without injury, it is necessary to understand the anatomical relationship among the branches of Glisson's sheath, hepatic veins, and tumor. In Japan, three-dimensional (3D) preoperative simulation for liver surgery is becoming increasingly common, and liver 3D modeling and 3D hepatectomy simulation by 3D analysis software for liver surgery have been covered by universal healthcare insurance since 2012. Herein, we review the history of virtual hepatectomy using computer-aided surgery (CAS) and our research to date, and we discuss the future prospects of CAS. We have used the SYNAPSE VINCENT medical imaging system (Fujifilm Medical, Tokyo, Japan) for 3D visualization and virtual resection of the liver since 2010. We developed a novel fusion imaging technique combining 3D computed tomography (CT) with magnetic resonance imaging (MRI). The fusion image enables us to easily visualize anatomic relationships among the hepatic arteries, portal veins, bile duct, and tumor in the hepatic hilum. In 2013, we developed an original software, called Liversim, that enables real-time deformation of the liver using physical simulation, and a randomized control trial has recently been conducted to evaluate the use of Liversim and SYNAPSE VINCENT for preoperative simulation and planning. Furthermore, we developed a novel hollow 3D-printed liver model whose surface is covered with frames. This model is useful for safe liver resection, has better visibility, and the production cost is reduced to one-third of a previous model. Preoperative simulation and navigation with CAS in liver resection are expected to help planning and conducting a surgery and surgical education. Thus, a novel CAS system will contribute to not only the performance of reliable hepatectomy but also to surgical education.

  19. Microfabricating 3D Structures by Laser Origami

    DTIC Science & Technology

    2011-11-09

    technique generates 3D microstructures by controlled out-of- plane folding of 2D patterns through a variety of laser-based digital fabrication...processes. Digital microfabrication techniques such as laser direct-write (LDW) offer a viable alternative for generating 3D self-folding designs. These...folding at the microscale where manual or mechanized actuation of the smaller struc- tures is not practical. LDW techniques allow micromachining and

  20. Spatioangular Prefiltering for Multiview 3D Displays.

    PubMed

    Ramachandra, Vikas; Hirakawa, Keigo; Zwicker, Matthias; Nguyen, Truong

    2011-05-01

    In this paper, we analyze the reproduction of light fields on multiview 3D displays. A three-way interaction between the input light field signal (which is often aliased), the joint spatioangular sampling grids of multiview 3D displays, and the interview light leakage in modern multiview 3D displays is characterized in the joint spatioangular frequency domain. Reconstruction of light fields by all physical 3D displays is prone to light leakage, which means that the reconstruction low-pass filter implemented by the display is too broad in the angular domain. As a result, 3D displays excessively attenuate angular frequencies. Our analysis shows that this reduces sharpness of the images shown in the 3D displays. In this paper, stereoscopic image recovery is recast as a problem of joint spatioangular signal reconstruction. The combination of the 3D display point spread function and human visual system provides the narrow-band low-pass filter which removes spectral replicas in the reconstructed light field on the multiview display. The nonideality of this filter is corrected with the proposed prefiltering. The proposed light field reconstruction method performs light field antialiasing as well as angular sharpening to compensate for the nonideal response of the 3D display. The union of cosets approach which has been used earlier by others is employed here to model the nonrectangular spatioangular sampling grids on a multiview display in a generic fashion. We confirm the effectiveness of our approach in simulation and in physical hardware, and demonstrate improvement over existing techniques.

  1. Auto convergence for stereoscopic 3D cameras

    NASA Astrophysics Data System (ADS)

    Zhang, Buyue; Kothandaraman, Sreenivas; Batur, Aziz Umit

    2012-03-01

    Viewing comfort is an important concern for 3-D capable consumer electronics such as 3-D cameras and TVs. Consumer generated content is typically viewed at a close distance which makes the vergence-accommodation conflict particularly pronounced, causing discomfort and eye fatigue. In this paper, we present a Stereo Auto Convergence (SAC) algorithm for consumer 3-D cameras that reduces the vergence-accommodation conflict on the 3-D display by adjusting the depth of the scene automatically. Our algorithm processes stereo video in realtime and shifts each stereo frame horizontally by an appropriate amount to converge on the chosen object in that frame. The algorithm starts by estimating disparities between the left and right image pairs using correlations of the vertical projections of the image data. The estimated disparities are then analyzed by the algorithm to select a point of convergence. The current and target disparities of the chosen convergence point determines how much horizontal shift is needed. A disparity safety check is then performed to determine whether or not the maximum and minimum disparity limits would be exceeded after auto convergence. If the limits would be exceeded, further adjustments are made to satisfy the safety limits. Finally, desired convergence is achieved by shifting the left and the right frames accordingly. Our algorithm runs real-time at 30 fps on a TI OMAP4 processor. It is tested using an OMAP4 embedded prototype stereo 3-D camera. It significantly improves 3-D viewing comfort.

  2. Assessing 3d Photogrammetry Techniques in Craniometrics

    NASA Astrophysics Data System (ADS)

    Moshobane, M. C.; de Bruyn, P. J. N.; Bester, M. N.

    2016-06-01

    Morphometrics (the measurement of morphological features) has been revolutionized by the creation of new techniques to study how organismal shape co-varies with several factors such as ecophenotypy. Ecophenotypy refers to the divergence of phenotypes due to developmental changes induced by local environmental conditions, producing distinct ecophenotypes. None of the techniques hitherto utilized could explicitly address organismal shape in a complete biological form, i.e. three-dimensionally. This study investigates the use of the commercial software, Photomodeler Scanner® (PMSc®) three-dimensional (3D) modelling software to produce accurate and high-resolution 3D models. Henceforth, the modelling of Subantarctic fur seal (Arctocephalus tropicalis) and Antarctic fur seal (Arctocephalus gazella) skulls which could allow for 3D measurements. Using this method, sixteen accurate 3D skull models were produced and five metrics were determined. The 3D linear measurements were compared to measurements taken manually with a digital caliper. In addition, repetitive measurements were recorded by varying researchers to determine repeatability. To allow for comparison straight line measurements were taken with the software, assuming that close accord with all manually measured features would illustrate the model's accurate replication of reality. Measurements were not significantly different demonstrating that realistic 3D skull models can be successfully produced to provide a consistent basis for craniometrics, with the additional benefit of allowing non-linear measurements if required.

  3. 3D steerable wavelets in practice.

    PubMed

    Chenouard, Nicolas; Unser, Michael

    2012-11-01

    We introduce a systematic and practical design for steerable wavelet frames in 3D. Our steerable wavelets are obtained by applying a 3D version of the generalized Riesz transform to a primary isotropic wavelet frame. The novel transform is self-reversible (tight frame) and its elementary constituents (Riesz wavelets) can be efficiently rotated in any 3D direction by forming appropriate linear combinations. Moreover, the basis functions at a given location can be linearly combined to design custom (and adaptive) steerable wavelets. The features of the proposed method are illustrated with the processing and analysis of 3D biomedical data. In particular, we show how those wavelets can be used to characterize directional patterns and to detect edges by means of a 3D monogenic analysis. We also propose a new inverse-problem formalism along with an optimization algorithm for reconstructing 3D images from a sparse set of wavelet-domain edges. The scheme results in high-quality image reconstructions which demonstrate the feature-reduction ability of the steerable wavelets as well as their potential for solving inverse problems.

  4. 3D Viscoelastic traction force microscopy.

    PubMed

    Toyjanova, Jennet; Hannen, Erin; Bar-Kochba, Eyal; Darling, Eric M; Henann, David L; Franck, Christian

    2014-10-28

    Native cell-material interactions occur on materials differing in their structural composition, chemistry, and physical compliance. While the last two decades have shown the importance of traction forces during cell-material interactions, they have been almost exclusively presented on purely elastic in vitro materials. Yet, most bodily tissue materials exhibit some level of viscoelasticity, which could play an important role in how cells sense and transduce tractions. To expand the realm of cell traction measurements and to encompass all materials from elastic to viscoelastic, this paper presents a general, and comprehensive approach for quantifying 3D cell tractions in viscoelastic materials. This methodology includes the experimental characterization of the time-dependent material properties for any viscoelastic material with the subsequent mathematical implementation of the determined material model into a 3D traction force microscopy (3D TFM) framework. Utilizing this new 3D viscoelastic TFM (3D VTFM) approach, we quantify the influence of viscosity on the overall material traction calculations and quantify the error associated with omitting time-dependent material effects, as is the case for all other TFM formulations. We anticipate that the 3D VTFM technique will open up new avenues of cell-material investigations on even more physiologically relevant time-dependent materials including collagen and fibrin gels.

  5. Focus-distance-controlled 3D TV

    NASA Astrophysics Data System (ADS)

    Yanagisawa, Nobuaki; Kim, Kyung-tae; Son, Jung-Young; Murata, Tatsuya; Orima, Takatoshi

    1996-09-01

    There is a phenomenon that a 3D image appears in proportion to a focus distance when something is watched through a convex lens. An adjustable focus lens which can control the focus distance of the convex lens is contrived and applied to 3D TV. We can watch 3D TV without eyeglasses. The 3D TV image meets the NTSC standard. A parallax data and a focus data about the image can be accommodated at the same time. A continuous image method realizes much wider views. An anti 3D image effect can be avoided by using this method. At present, an analysis of proto-type lens and experiment are being carried out. As a result, a phantom effect and a viewing area can be improved. It is possible to watch the 3D TV at any distance. Distance data are triangulated by two cameras. A plan of AVI photo type using ten thousand lenses is discussed. This method is compared with four major conventional methods. As a result, it is revealed that this method can make the efficient use of Integral Photography and Varifocal type method. In the case of Integral Photography, a miniaturization of this system is possible. But it is difficult to get actual focus. In the case of varifocal type method, there is no problem with focusing, but the miniaturization is impossible. The theory investigated in this paper makes it possible to solve these problems.

  6. Focus-distance-controlled 3D TV

    NASA Astrophysics Data System (ADS)

    Yanagisawa, Nobuaki; Kim, Kyung-tae; Son, Jung-Young; Murata, Tatsuya; Orima, Takatoshi

    1997-05-01

    There is a phenomenon that a 3D image appears in proportion to a focus distance when something is watched through a convex lens. An adjustable focus lens which can control the focus distance of the convex lens is contrived and applied to 3D TV. We can watch 3D TV without eyeglasses. The 3D TV image meets the NTSC standard. A parallax data and a focus data about the image can be accommodated at the same time. A continuous image method realizes much wider views. An anti 3D image effect can be avoided by using this method. At present, an analysis of proto-type lens and experiment are being carried out. As a result, a phantom effect and a viewing area can be improved. It is possible to watch the 3D TV at any distance. Distance data are triangulated by two cameras. A plan of AVI proto type using ten thousands lenses is discussed. This method is compared with four major conventional methods. As a result, it is revealed that this method can make the efficient use of integral photography and varifocal type method. In the case of integral photography, a miniaturization of this system is possible. But it is difficult to get actual focus. In the case of varifocal type method, there is no problem with focusing, but the miniaturization is impossible. The theory investigated in this paper makes it possible to solve these problems.

  7. The NIH 3D Print Exchange: A Public Resource for Bioscientific and Biomedical 3D Prints

    PubMed Central

    Coakley, Meghan F.; Hurt, Darrell E.; Weber, Nick; Mtingwa, Makazi; Fincher, Erin C.; Alekseyev, Vsevelod; Chen, David T.; Yun, Alvin; Gizaw, Metasebia; Swan, Jeremy; Yoo, Terry S.; Huyen, Yentram

    2016-01-01

    The National Institutes of Health (NIH) has launched the NIH 3D Print Exchange, an online portal for discovering and creating bioscientifically relevant 3D models suitable for 3D printing, to provide both researchers and educators with a trusted source to discover accurate and informative models. There are a number of online resources for 3D prints, but there is a paucity of scientific models, and the expertise required to generate and validate such models remains a barrier. The NIH 3D Print Exchange fills this gap by providing novel, web-based tools that empower users with the ability to create ready-to-print 3D files from molecular structure data, microscopy image stacks, and computed tomography scan data. The NIH 3D Print Exchange facilitates open data sharing in a community-driven environment, and also includes various interactive features, as well as information and tutorials on 3D modeling software. As the first government-sponsored website dedicated to 3D printing, the NIH 3D Print Exchange is an important step forward to bringing 3D printing to the mainstream for scientific research and education. PMID:28367477

  8. First 3D view of solar eruptions

    NASA Astrophysics Data System (ADS)

    2004-07-01

    arrival times and impact angles at the Earth," says Dr Thomas Moran of the Catholic University, Washington, USA. In collaboration with Dr Joseph Davila, of NASA’s Goddard Space Flight Center, Greenbelt, USA, Moran has analysed two-dimensional images from the ESA/NASA Solar and Heliospheric Observatory (SOHO) in a new way to yield 3D images. Their technique is able to reveal the complex and distorted magnetic fields that travel with the CME cloud and sometimes interact with Earth's own magnetic field, pouring tremendous amounts of energy into the space near Earth. "These magnetic fields are invisible," Moran explains, "but since the CME gas is electrified, it spirals around the magnetic fields, tracing out their shapes." Therefore, a 3D view of the CME electrified gas (called a plasma) gives scientists valuable information on the structure and behaviour of the magnetic fields powering the CME. The new analysis technique for SOHO data determines the three-dimensional structure of a CME by taking a sequence of three SOHO Large Angle and Spectrometric Coronagraph (LASCO) images through various polarisers, at different angles. Whilst the light emitted by the Sun is not polarised, once it is scattered off electrons in the CME plasma it takes up some polarisation. This means that the electric fields of some of the scattered light are forced to oscillate in certain directions, whereas the electric field in the light emitted by the Sun is free to oscillate in all directions. Moran and Davila knew that light from CME structures closer to the plane of the Sun (as seen on the LASCO images) had to be more polarised than light from structures farther from that plane. Thus, by computing the ratio of polarised to unpolarised light for each CME structure, they could measure its distance from the plane. This provided the missing third dimension to the LASCO images. With this technique, the team has confirmed that the structure of CMEs directed towards Earth is an expanding arcade of

  9. CFL3D, FUN3d, and NSU3D Contributions to the Fifth Drag Prediction Workshop

    NASA Technical Reports Server (NTRS)

    Park, Michael A.; Laflin, Kelly R.; Chaffin, Mark S.; Powell, Nicholas; Levy, David W.

    2013-01-01

    Results presented at the Fifth Drag Prediction Workshop using CFL3D, FUN3D, and NSU3D are described. These are calculations on the workshop provided grids and drag adapted grids. The NSU3D results have been updated to reflect an improvement to skin friction calculation on skewed grids. FUN3D results generated after the workshop are included for custom participant generated grids and a grid from a previous workshop. Uniform grid refinement at the design condition shows a tight grouping in calculated drag, where the variation in the pressure component of drag is larger than the skin friction component. At this design condition, A fine-grid drag value was predicted with a smaller drag adjoint adapted grid via tetrahedral adaption to a metric and mixed-element subdivision. The buffet study produced larger variation than the design case, which is attributed to large differences in the predicted side-of-body separation extent. Various modeling and discretization approaches had a strong impact on predicted side-of-body separation. This large wing root separation bubble was not observed in wind tunnel tests indicating that more work is necessary in modeling wing root juncture flows to predict experiments.

  10. Fabrication of Ion-Shaped Anisotropic Nanoparticles and their Orientational Imaging by Second-Harmonic Generation Microscopy

    PubMed Central

    Slablab, Abdallah; Isotalo, Tero J.; Mäkitalo, Jouni; Turquet, Léo; Coulon, Pierre-Eugène; Niemi, Tapio; Ulysse, Christian; Kociak, Mathieu; Mailly, Dominique; Rizza, Giancarlo; Kauranen, Martti

    2016-01-01

    Ion beam shaping is a novel and powerful tool to engineer nanocomposites with effective three-dimensional (3D) architectures. In particular, this technique offers the possibility to precisely control the size, shape and 3D orientation of metallic nanoparticles at the nanometer scale while keeping the particle volume constant. Here, we use swift heavy ions of xenon for irradiation in order to successfully fabricate nanocomposites consisting of anisotropic gold nanoparticle that are oriented in 3D and embedded in silica matrix. Furthermore, we investigate individual nanorods using a nonlinear optical microscope based on second-harmonic generation (SHG). A tightly focused linearly or radially-polarized laser beam is used to excite nanorods with different orientations. We demonstrate high sensitivity of the SHG response for these polarizations to the orientation of the nanorods. The SHG measurements are in excellent agreement with the results of numerical modeling based on the boundary element method. PMID:27881838

  11. Fabrication of Ion-Shaped Anisotropic Nanoparticles and their Orientational Imaging by Second-Harmonic Generation Microscopy

    NASA Astrophysics Data System (ADS)

    Slablab, Abdallah; Isotalo, Tero J.; Mäkitalo, Jouni; Turquet, Léo; Coulon, Pierre-Eugène; Niemi, Tapio; Ulysse, Christian; Kociak, Mathieu; Mailly, Dominique; Rizza, Giancarlo; Kauranen, Martti

    2016-11-01

    Ion beam shaping is a novel and powerful tool to engineer nanocomposites with effective three-dimensional (3D) architectures. In particular, this technique offers the possibility to precisely control the size, shape and 3D orientation of metallic nanoparticles at the nanometer scale while keeping the particle volume constant. Here, we use swift heavy ions of xenon for irradiation in order to successfully fabricate nanocomposites consisting of anisotropic gold nanoparticle that are oriented in 3D and embedded in silica matrix. Furthermore, we investigate individual nanorods using a nonlinear optical microscope based on second-harmonic generation (SHG). A tightly focused linearly or radially-polarized laser beam is used to excite nanorods with different orientations. We demonstrate high sensitivity of the SHG response for these polarizations to the orientation of the nanorods. The SHG measurements are in excellent agreement with the results of numerical modeling based on the boundary element method.

  12. Modeling radiative transfer in heterogeneous 3D vegetation canopies

    NASA Astrophysics Data System (ADS)

    Gastellu-Etchegorry, J. P.; Demarez, V.; Pinel, Veronique; Zagolski, Francis

    1995-01-01

    The DART (discrete anisotropic radiative transfer) model simulates radiative transfer in heterogeneous 3-D scenes; here, a forest plantation. Similarly to Kimes model, the scene is divided into a rectangular cell matrix, i.e., a building block for simulating larger scenes. Cells are parallelipipedic. The scene encompasses different landscape features (i.e., trees with leaves and trunks, grass, water, and soil) with specific optical (reflectance, transmittance) and structural (LAI, LAD) characteristics. Radiation directions are subdivided into contiguous sectors with possibly uneven spacing. Topography, hot spot, and multiple interactions (scattering, attenuation) within cells are modeled. Two major steps are distinguished: (1) Illumination of cells by direct sun radiation. Actual locations of within cell scattering are determined for optimizing scattering computation. (2) Interception and scattering of previously scattered radiation. Diffuse atmospheric radiation is input at this level. Multiple scattering is represented with a spherical harmonic decomposition, for reducing data volume. The model iterates on step 2 for all cells, and stops with the energetic equilibrium. This model predicts the bi-directional reflectance factors of 3D canopies, with each scene component contribution; it was successfully tested with homogeneous covers. It gives also the radiation regime with canopies, and consequently some information about volume distribution of photosynthesis rates and primary production.

  13. Developing novel 3D antennas using advanced additive manufacturing technology

    NASA Astrophysics Data System (ADS)

    Mirzaee, Milad

    In today's world of wireless communication systems, antenna engineering is rapidly advancing as the wireless services continue to expand in support of emerging commercial applications. Antennas play a key role in the performance of advanced transceiver systems where they serve to convert electric power to electromagnetic waves and vice versa. Researchers have held significant interest in developing this crucial component for wireless communication systems by employing a variety of design techniques. In the past few years, demands for electrically small antennas continues to increase, particularly among portable and mobile wireless devices, medical electronics and aerospace systems. This trend toward smaller electronic devices makes the three dimensional (3D) antennas very appealing, since they can be designed in a way to use every available space inside the devise. Additive Manufacturing (AM) method could help to find great solutions for the antennas design for next generation of wireless communication systems. In this thesis, the design and fabrication of 3D printed antennas using AM technology is studied. To demonstrate this application of AM, different types of antennas structures have been designed and fabricated using various manufacturing processes. This thesis studies, for the first time, embedded conductive 3D printed antennas using PolyLactic Acid (PLA) and Acrylonitrile Butadiene Styrene (ABS) for substrate parts and high temperature carbon paste for conductive parts which can be a good candidate to overcome the limitations of direct printing on 3D surfaces that is the most popular method to fabricate conductive parts of the antennas. This thesis also studies, for the first time, the fabrication of antennas with 3D printed conductive parts which can contribute to the new generation of 3D printed antennas.

  14. Stereoscopic contents authoring system for 3D DMB data service

    NASA Astrophysics Data System (ADS)

    Lee, BongHo; Yun, Kugjin; Hur, Namho; Kim, Jinwoong; Lee, SooIn

    2009-02-01

    This paper presents a stereoscopic contents authoring system that covers the creation and editing of stereoscopic multimedia contents for the 3D DMB (Digital Multimedia Broadcasting) data services. The main concept of 3D DMB data service is that, instead of full 3D video, partial stereoscopic objects (stereoscopic JPEG, PNG and MNG) are stereoscopically displayed on the 2D background video plane. In order to provide stereoscopic objects, we design and implement a 3D DMB content authoring system which provides the convenient and straightforward contents creation and editing functionalities. For the creation of stereoscopic contents, we mainly focused on two methods: CG (Computer Graphics) based creation and real image based creation. In the CG based creation scenario where the generated CG data from the conventional MAYA or 3DS MAX tool is rendered to generate the stereoscopic images by applying the suitable disparity and camera parameters, we use X-file for the direct conversion to stereoscopic objects, so called 3D DMB objects. In the case of real image based creation, the chroma-key method is applied to real video sequences to acquire the alpha-mapped images which are in turn directly converted to stereoscopic objects. The stereoscopic content editing module includes the timeline editor for both the stereoscopic video and stereoscopic objects. For the verification of created stereoscopic contents, we implemented the content verification module to verify and modify the contents by adjusting the disparity. The proposed system will leverage the power of stereoscopic contents creation for mobile 3D data service especially targeted for T-DMB with the capabilities of CG and real image based contents creation, timeline editing and content verification.

  15. Measurements of 3D slip velocities and plasma column lengths of a gliding arc discharge

    SciTech Connect

    Zhu, Jiajian; Gao, Jinlong; Ehn, Andreas; Aldén, Marcus; Li, Zhongshan E-mail: alpers@ma.tum.de; Moseev, Dmitry; Kusano, Yukihiro; Salewski, Mirko; Alpers, Andreas E-mail: alpers@ma.tum.de; Gritzmann, Peter; Schwenk, Martin

    2015-01-26

    A non-thermal gliding arc discharge was generated at atmospheric pressure in an air flow. The dynamics of the plasma column and tracer particles were recorded using two synchronized high-speed cameras. Whereas the data analysis for such systems has previously been performed in 2D (analyzing the single camera image), we provide here a 3D data analysis that includes 3D reconstructions of the plasma column and 3D particle tracking velocimetry based on discrete tomography methods. The 3D analysis, in particular, the determination of the 3D slip velocity between the plasma column and the gas flow, gives more realistic insight into the convection cooling process. Additionally, with the determination of the 3D slip velocity and the 3D length of the plasma column, we give more accurate estimates for the drag force, the electric field strength, the power per unit length, and the radius of the conducting zone of the plasma column.

  16. Genome3D: exploiting structure to help users understand their sequences

    PubMed Central

    Lewis, Tony E.; Sillitoe, Ian; Andreeva, Antonina; Blundell, Tom L.; Buchan, Daniel W.A.; Chothia, Cyrus; Cozzetto, Domenico; Dana, José M.; Filippis, Ioannis; Gough, Julian; Jones, David T.; Kelley, Lawrence A.; Kleywegt, Gerard J.; Minneci, Federico; Mistry, Jaina; Murzin, Alexey G.; Ochoa-Montaño, Bernardo; Oates, Matt E.; Punta, Marco; Rackham, Owen J.L.; Stahlhacke, Jonathan; Sternberg, Michael J.E.; Velankar, Sameer; Orengo, Christine

    2015-01-01

    Genome3D (http://www.genome3d.eu) is a collaborative resource that provides predicted domain annotations and structural models for key sequences. Since introducing Genome3D in a previous NAR paper, we have substantially extended and improved the resource. We have annotated representatives from Pfam families to improve coverage of diverse sequences and added a fast sequence search to the website to allow users to find Genome3D-annotated sequences similar to their own. We have improved and extended the Genome3D data, enlarging the source data set from three model organisms to 10, and adding VIVACE, a resource new to Genome3D. We have analysed and updated Genome3D's SCOP/CATH mapping. Finally, we have improved the superposition tools, which now give users a more powerful interface for investigating similarities and differences between structural models. PMID:25348407

  17. Assessment of the ability of myocardial contrast echocardiography with harmonic power Doppler imaging to identify perfusion abnormalities in patients with Kawasaki disease at rest and during dipyridamole stress.

    PubMed

    Ishii, M; Himeno, W; Sawa, M; Iemura, M; Furui, J; Muta, H; Sugahara, Y; Egami, K; Akagi, T; Ishibashi, M; Kato, H

    2002-01-01

    The aim of our study was to assess the ability of myocardial contrast echocardiography (MCE) with harmonic power Doppler imaging (HPDI) to identify perfusion abnormalities in patients with Kawasaki disease at rest and during pharmacological stress imaging with dipyridamole. Results were compared with those of 99mTc-tetrofosmin single-photon emission computed tomography (SPECT) imaging as the clinical reference standard. MCE with HPDI was performed on 20 patients with a history of Kawasaki disease. Images were obtained at baseline and during dipyridamole infusion (0.56 mg x kg(-1)) in the apical two- and four-chamber views. Myocardial opacification suitable for the analysis was obtained in all patients. Nine patients with stenotic lesions had a reversible defect after dipyridamole infusion detected by both MCE with HPDI and SPECT, and 3 patients with a history of myocardial infarction had a partially or completely irreversible defect detected by both methods. Three patients with coronary aneurysm without stenotic lesion, 4 patients with regressed coronary aneurysm, and 2 patients with normal coronary artery in acute phase also had normal perfusion at rest and after pharmacological stress by both methods. A 96% concordance (kappa = 0.87) was obtained when comparing the respective segmental perfusion scores using the two methods at baseline, and an 86% concordance (kappa = 0.81) was obtained at postdipyridamole infusion. After combining baseline and postdipyridamole images, each segment was labeled as having normal perfusion, irreversible defects, or reversible defects. Using these classifications, concordance for the two methods was 92% (kappa = 0.87). MCE with HPDI is a safe and feasible method by which to detect asymptomatic ischemia due to severe stenotic lesion, and it may be an important addition to the modalities used to identify patients at risk for myocardial infarction as a complication of Kawasaki disease.

  18. Nonlinear harmonic generation and proposed experimental verification in SASE FELs.

    SciTech Connect

    Biedron, S. G.; Freund, H. P.; Milton, S. V.

    1999-08-24

    Recently, a 3D, polychromatic, nonlinear simulation code was developed to study the growth of nonlinear harmonics in self-amplified spontaneous emission (SASE) free-electron lasers (FELs). The simulation was applied to the parameters for each stage of the Advanced Photon Source (APS) SASE FEL, intended for operation in the visible, UV, and short UV wavelength regimes, respectively, to study the presence of nonlinear harmonic generation. Significant nonlinear harmonic growth is seen. Here, a discussion of the code development, the APS SASE FEL, the simulations and results, and, finally, the proposed experimental procedure for verification of such nonlinear harmonic generation at the APS SASE FEL will be given.

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

    SciTech Connect

    Yan Jianhua; Li Jialu

    1994-12-31

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

  20. Transforming Wind Turbine Blade Mold Manufacturing with 3D Printing

    SciTech Connect

    Zayas, Jose; Johnson, Mark

    2016-06-28

    Innovation in the design and manufacturing of wind power generation components continues to be critical to achieving our national renewable energy goals. As a result of this challenge, the U.S. Department of Energy's Wind Program and Advanced Manufacturing Office are partnering with public and private organizations to apply additive manufacturing, commonly known as 3D printing, to the production of wind turbine blade molds.

  1. Transforming Wind Turbine Blade Mold Manufacturing with 3D Printing

    ScienceCinema

    Zayas, Jose; Johnson, Mark

    2016-08-17

    Innovation in the design and manufacturing of wind power generation components continues to be critical to achieving our national renewable energy goals. As a result of this challenge, the U.S. Department of Energy's Wind Program and Advanced Manufacturing Office are partnering with public and private organizations to apply additive manufacturing, commonly known as 3D printing, to the production of wind turbine blade molds.

  2. Seeing a Stellar Explosion in 3D

    NASA Astrophysics Data System (ADS)

    2010-08-01

    Astronomers using ESO's Very Large Telescope have for the first time obtained a three-dimensional view of the distribution of the innermost material expelled by a recently exploded star. The original blast was not only powerful, according to the new results. It was also more concentrated in one particular direction. This is a strong indication that the supernova must have been very turbulent, supporting the most recent computer models. Unlike the Sun, which will die rather quietly, massive stars arriving at the end of their brief life explode as supernovae, hurling out a vast quantity of material. In this class, Supernova 1987A (SN 1987A) in the rather nearby Large Magellanic Cloud occupies a very special place. Seen in 1987, it was the first naked-eye supernova to be observed for 383 years (eso8704), and because of its relative closeness, it has made it possible for astronomers to study the explosion of a massive star and its aftermath in more detail than ever before. It is thus no surprise that few events in modern astronomy have been met with such an enthusiastic response by scientists. SN 1987A has been a bonanza for astrophysicists (eso8711 and eso0708). It provided several notable observational 'firsts', like the detection of neutrinos from the collapsing inner stellar core triggering the explosion, the localisation on archival photographic plates of the star before it exploded, the signs of an asymmetric explosion, the direct observation of the radioactive elements produced during the blast, observation of the formation of dust in the supernova, as well as the detection of circumstellar and interstellar material (eso0708). New observations making use of a unique instrument, SINFONI [1], on ESO's Very Large Telescope (VLT) have provided even deeper knowledge of this amazing event, as astronomers have now been able to obtain the first-ever 3D reconstruction of the central parts of the exploding material. This view shows that the explosion was stronger and

  3. The capture and recreation of 3D auditory scenes

    NASA Astrophysics Data System (ADS)

    Li, Zhiyun

    The main goal of this research is to develop the theory and implement practical tools (in both software and hardware) for the capture and recreation of 3D auditory scenes. Our research is expected to have applications in virtual reality, telepresence, film, music, video games, auditory user interfaces, and sound-based surveillance. The first part of our research is concerned with sound capture via a spherical microphone array. The advantage of this array is that it can be steered into any 3D directions digitally with the same beampattern. We develop design methodologies to achieve flexible microphone layouts, optimal beampattern approximation and robustness constraint. We also design novel hemispherical and circular microphone array layouts for more spatially constrained auditory scenes. Using the captured audio, we then propose a unified and simple approach for recreating them by exploring the reciprocity principle that is satisfied between the two processes. Our approach makes the system easy to build, and practical. Using this approach, we can capture the 3D sound field by a spherical microphone array and recreate it using a spherical loudspeaker array, and ensure that the recreated sound field matches the recorded field up to a high order of spherical harmonics. For some regular or semi-regular microphone layouts, we design an efficient parallel implementation of the multi-directional spherical beamformer by using the rotational symmetries of the beampattern and of the spherical microphone array. This can be implemented in either software or hardware and easily adapted for other regular or semi-regular layouts of microphones. In addition, we extend this approach for headphone-based system. Design examples and simulation results are presented to verify our algorithms. Prototypes are built and tested in real-world auditory scenes.

  4. Observing molecular dynamics with time-resolved 3D momentum imaging

    NASA Astrophysics Data System (ADS)

    Sturm, F. P.; Wright, T.; Bocharova, I.; Ray, D.; Shivaram, N.; Cryan, J.; Belkacem, A.; Weber, T.; Dörner, R.

    2014-05-01

    Photo-excitation and ionization trigger rich dynamics in molecular systems which play a key role in many important processes in nature such as vision, photosynthesis or photoprotection. Observing those reactions in real-time without significantly disturbing the molecules by a strong electric field has been a great challenge. Recent experiments using Time-of-Flight and Velocity Map Imaging techniques have revealed important information on the dynamics of small molecular systems upon photo-excitation. We have developed an apparatus for time-resolved momentum imaging of electrons and ions in all three spatial dimensions that employs two-color femtosecond laser pulses in the vacuum and extreme ultraviolet (VUV, XUV) for probing molecular dynamics. Our COLTRIMS style reaction microscope can measure electrons and ions in coincidence and reconstruct the momenta of the reaction fragments in 3D. We use a high power 800 nm laser in a loose focusing geometry gas cell to efficinetly drive High Harmonic Generation. The resulting photon flux is sufficient to perform 2-photon pump-probe experiments using VUV and XUV pulses for both pump and probe. With this setup we investigate non-Born-Oppenheimer dynamics in small molecules such as C2H4 and CO2 on a femtosecond time scale. Supported by Chemical Sciences, Geosciences and Biosciences division of BES/DOE.

  5. Intersymbol Interference Investigations Using a 3D Time-Dependent Traveling Wave Tube Model

    NASA Technical Reports Server (NTRS)

    Kory, Carol L.; Andro, Monty

    2002-01-01

    For the first time, a time-dependent, physics-based computational model has been used to provide a direct description of the effects of the traveling wave tube amplifier (TWTA) on modulated digital signals. The TWT model comprehensively takes into account the effects of frequency dependent AM/AM and AM/PM conversion; gain and phase ripple; drive-induced oscillations; harmonic generation; intermodulation products; and backward waves. Thus, signal integrity can be investigated in the presence of these sources of potential distortion as a function of the physical geometry and operating characteristics of the high power amplifier and the operational digital signal. This method promises superior predictive fidelity compared to methods using TWT models based on swept- amplitude and/or swept-frequency data. First, the TWT model using the three dimensional (3D) electromagnetic code MAFIA is presented. Then, this comprehensive model is used to investigate approximations made in conventional TWT black-box models used in communication system level simulations. To quantitatively demonstrate the effects these approximations have on digital signal performance predictions, including intersymbol interference (ISI), the MAFIA results are compared to the system level analysis tool, Signal Processing Workstation (SPW), using high order modulation schemes including 16 and 64-QAM.

  6. Intersymbol Interference Investigations Using a 3D Time-Dependent Traveling Wave Tube Model

    NASA Technical Reports Server (NTRS)

    Kory, Carol L.; Andro, Monty; Downey, Alan (Technical Monitor)

    2001-01-01

    For the first time, a physics based computational model has been used to provide a direct description of the effects of the TWT (Traveling Wave Tube) on modulated digital signals. The TWT model comprehensively takes into account the effects of frequency dependent AM/AM and AM/PM conversion; gain and phase ripple; drive-induced oscillations; harmonic generation; intermodulation products; and backward waves. Thus, signal integrity can be investigated in the presence of these sources of potential distortion as a function of the physical geometry of the high power amplifier and the operational digital signal. This method promises superior predictive fidelity compared to methods using TWT models based on swept amplitude and/or swept frequency data. The fully three-dimensional (3D), time-dependent, TWT interaction model using the electromagnetic code MAFIA is presented. This model is used to investigate assumptions made in TWT black box models used in communication system level simulations. In addition, digital signal performance, including intersymbol interference (ISI), is compared using direct data input into the MAFIA model and using the system level analysis tool, SPW (Signal Processing Worksystem).

  7. Self assembled structures for 3D integration

    NASA Astrophysics Data System (ADS)

    Rao, Madhav

    Three dimensional (3D) micro-scale structures attached to a silicon substrate have various applications in microelectronics. However, formation of 3D structures using conventional micro-fabrication techniques are not efficient and require precise control of processing parameters. Self assembly is a method for creating 3D structures that takes advantage of surface area minimization phenomena. Solder based self assembly (SBSA), the subject of this dissertation, uses solder as a facilitator in the formation of 3D structures from 2D patterns. Etching a sacrificial layer underneath a portion of the 2D pattern allows the solder reflow step to pull those areas out of the substrate plane resulting in a folded 3D structure. Initial studies using the SBSA method demonstrated low yields in the formation of five different polyhedra. The failures in folding were primarily attributed to nonuniform solder deposition on the underlying metal pads. The dip soldering method was analyzed and subsequently refined. A modified dip soldering process provided improved yield among the polyhedra. Solder bridging referred as joining of solder deposited on different metal patterns in an entity influenced the folding mechanism. In general, design parameters such as small gap-spacings and thick metal pads were found to favor solder bridging for all patterns studied. Two types of soldering: face and edge soldering were analyzed. Face soldering refers to the application of solder on the entire metal face. Edge soldering indicates application of solder only on the edges of the metal face. Mechanical grinding showed that face soldered SBSA structures were void free and robust in nature. In addition, the face soldered 3D structures provide a consistent heat resistant solder standoff height that serve as attachments in the integration of dissimilar electronic technologies. Face soldered 3D structures were developed on the underlying conducting channel to determine the thermo-electric reliability of

  8. PLOT3D Export Tool for Tecplot

    NASA Technical Reports Server (NTRS)

    Alter, Stephen

    2010-01-01

    The PLOT3D export tool for Tecplot solves the problem of modified data being impossible to output for use by another computational science solver. The PLOT3D Exporter add-on enables the use of the most commonly available visualization tools to engineers for output of a standard format. The exportation of PLOT3D data from Tecplot has far reaching effects because it allows for grid and solution manipulation within a graphical user interface (GUI) that is easily customized with macro language-based and user-developed GUIs. The add-on also enables the use of Tecplot as an interpolation tool for solution conversion between different grids of different types. This one add-on enhances the functionality of Tecplot so significantly, it offers the ability to incorporate Tecplot into a general suite of tools for computational science applications as a 3D graphics engine for visualization of all data. Within the PLOT3D Export Add-on are several functions that enhance the operations and effectiveness of the add-on. Unlike Tecplot output functions, the PLOT3D Export Add-on enables the use of the zone selection dialog in Tecplot to choose which zones are to be written by offering three distinct options - output of active, inactive, or all zones (grid blocks). As the user modifies the zones to output with the zone selection dialog, the zones to be written are similarly updated. This enables the use of Tecplot to create multiple configurations of a geometry being analyzed. For example, if an aircraft is loaded with multiple deflections of flaps, by activating and deactivating different zones for a specific flap setting, new specific configurations of that aircraft can be easily generated by only writing out specific zones. Thus, if ten flap settings are loaded into Tecplot, the PLOT3D Export software can output ten different configurations, one for each flap setting.

  9. A microfluidic device for 2D to 3D and 3D to 3D cell navigation

    NASA Astrophysics Data System (ADS)

    Shamloo, Amir; Amirifar, Leyla

    2016-01-01

    Microfluidic devices have received wide attention and shown great potential in the field of tissue engineering and regenerative medicine. Investigating cell response to various stimulations is much more accurate and comprehensive with the aid of microfluidic devices. In this study, we introduced a microfluidic device by which the matrix density as a mechanical property and the concentration profile of a biochemical factor as a chemical property could be altered. Our microfluidic device has a cell tank and a cell culture chamber to mimic both 2D to 3D and 3D to 3D migration of three types of cells. Fluid shear stress is negligible on the cells and a stable concentration gradient can be obtained by diffusion. The device was designed by a numerical simulation so that the uniformity of the concentration gradients throughout the cell culture chamber was obtained. Adult neural cells were cultured within this device and they showed different branching and axonal navigation phenotypes within varying nerve growth factor (NGF) concentration profiles. Neural stem cells were also cultured within varying collagen matrix densities while exposed to NGF concentrations and they experienced 3D to 3D collective migration. By generating vascular endothelial growth factor concentration gradients, adult human dermal microvascular endothelial cells also migrated in a 2D to 3D manner and formed a stable lumen within a specific collagen matrix density. It was observed that a minimum absolute concentration and concentration gradient were required to stimulate migration of all types of the cells. This device has the advantage of changing multiple parameters simultaneously and is expected to have wide applicability in cell studies.

  10. Patient-specific dosimetry based on quantitative SPECT imaging and 3D-DFT convolution

    SciTech Connect

    Akabani, G.; Hawkins, W.G.; Eckblade, M.B.; Leichner, P.K.

    1999-01-01

    The objective of this study was to validate the use of a 3-D discrete Fourier Transform (3D-DFT) convolution method to carry out the dosimetry for I-131 for soft tissues in radioimmunotherapy procedures. To validate this convolution method, mathematical and physical phantoms were used as a basis of comparison with Monte Carlo transport (MCT) calculations which were carried out using the EGS4 system code. The mathematical phantom consisted of a sphere containing uniform and nonuniform activity distributions. The physical phantom consisted of a cylinder containing uniform and nonuniform activity distributions. Quantitative SPECT reconstruction was carried out using the Circular Harmonic Transform (CHT) algorithm.

  11. A Tetraperylene Diimides Based 3D Nonfullerene Acceptor for Efficient Organic Photovoltaics.

    PubMed

    Liu, Shi-Yong; Wu, Chen-Hao; Li, Chang-Zhi; Liu, Sheng-Qiang; Wei, Kung-Hwa; Chen, Hong-Zheng; Jen, Alex K-Y

    2015-04-01

    A nonfullerene acceptor based on a 3D tetraperylene diimide is developed for bulk heterojunction organic photovoltaics. The disruption of perylene diimide planarity with a 3D framework suppresses the self-aggregation of perylene diimide and inhibits excimer formation. From planar monoperylene diimide to 3D tetraperylene diimide, a significant improvement of power conversion efficiency from 0.63% to 3.54% can be achieved.

  12. Energy flow in passive and active 3D cochlear model

    SciTech Connect

    Wang, Yanli; Steele, Charles; Puria, Sunil

    2015-12-31

    Energy flow in the cochlea is an important characteristic of the cochlear traveling wave, and many investigators, such as von Békésy and Lighthill, have discussed this phenomenon. Particularly after the discovery of the motility of the outer hair cells (OHCs), the nature of the power gain of the cochlea has been a fundamental research question. In the present work, direct three-dimensional (3D) calculations of the power on cross sections of the cochlea and on the basilar membrane are performed based on a box model of the mouse cochlea. The distributions of the fluid pressure and fluid velocity in the scala vestibuli are presented. The power output from the OHCs and the power loss due to fluid viscous damping are calculated along the length of the cochlea. This work provides a basis for theoretical calculations of the power gain of the OHCs from mechanical considerations.

  13. Energy flow in passive and active 3D cochlear model

    NASA Astrophysics Data System (ADS)

    Wang, Yanli; Puria, Sunil; Steele, Charles

    2015-12-01

    Energy flow in the cochlea is an important characteristic of the cochlear traveling wave, and many investigators, such as von Békésy and Lighthill, have discussed this phenomenon. Particularly after the discovery of the motility of the outer hair cells (OHCs), the nature of the power gain of the cochlea has been a fundamental research question. In the present work, direct three-dimensional (3D) calculations of the power on cross sections of the cochlea and on the basilar membrane are performed based on a box model of the mouse cochlea. The distributions of the fluid pressure and fluid velocity in the scala vestibuli are presented. The power output from the OHCs and the power loss due to fluid viscous damping are calculated along the length of the cochlea. This work provides a basis for theoretical calculations of the power gain of the OHCs from mechanical considerations.

  14. RAG-3D: A search tool for RNA 3D substructures

    SciTech Connect

    Zahran, Mai; Sevim Bayrak, Cigdem; Elmetwaly, Shereef; Schlick, Tamar

    2015-08-24

    In this study, to address many challenges in RNA structure/function prediction, the characterization of RNA's modular architectural units is required. Using the RNA-As-Graphs (RAG) database, we have previously explored the existence of secondary structure (2D) submotifs within larger RNA structures. Here we present RAG-3D—a dataset of RNA tertiary (3D) structures and substructures plus a web-based search tool—designed to exploit graph representations of RNAs for the goal of searching for similar 3D structural fragments. The objects in RAG-3D consist of 3D structures translated into 3D graphs, cataloged based on the connectivity between their secondary structure elements. Each graph is additionally described in terms of its subgraph building blocks. The RAG-3D search tool then compares a query RNA 3D structure to those in the database to obtain structurally similar structures and substructures. This comparison reveals conserved 3D RNA features and thus may suggest functional connections. Though RNA search programs based on similarity in sequence, 2D, and/or 3D structural elements are available, our graph-based search tool may be advantageous for illuminating similarities that are not obvious; using motifs rather than sequence space also reduces search times considerably. Ultimately, such substructuring could be useful for RNA 3D structure prediction, structure/function inference and inverse folding.

  15. RAG-3D: A search tool for RNA 3D substructures

    DOE PAGES

    Zahran, Mai; Sevim Bayrak, Cigdem; Elmetwaly, Shereef; ...

    2015-08-24

    In this study, to address many challenges in RNA structure/function prediction, the characterization of RNA's modular architectural units is required. Using the RNA-As-Graphs (RAG) database, we have previously explored the existence of secondary structure (2D) submotifs within larger RNA structures. Here we present RAG-3D—a dataset of RNA tertiary (3D) structures and substructures plus a web-based search tool—designed to exploit graph representations of RNAs for the goal of searching for similar 3D structural fragments. The objects in RAG-3D consist of 3D structures translated into 3D graphs, cataloged based on the connectivity between their secondary structure elements. Each graph is additionally describedmore » in terms of its subgraph building blocks. The RAG-3D search tool then compares a query RNA 3D structure to those in the database to obtain structurally similar structures and substructures. This comparison reveals conserved 3D RNA features and thus may suggest functional connections. Though RNA search programs based on similarity in sequence, 2D, and/or 3D structural elements are available, our graph-based search tool may be advantageous for illuminating similarities that are not obvious; using motifs rather than sequence space also reduces search times considerably. Ultimately, such substructuring could be useful for RNA 3D structure prediction, structure/function inference and inverse folding.« less

  16. High Harmonic Fast Wave Heating and Current Drive for NSTX

    NASA Astrophysics Data System (ADS)

    Robinson, J. A.; Majeski, R.; Menard, J.; Ono, M.; Phillips, C. K.; Wilson, J. R.; Batchelor, D. B.; Carter, M. D.; Jaeger, E. F.; Smithe, D.

    1996-11-01

    Heating and noninductive current drive in NSTX will initially be accomplished with 6 MW of radio-frequency (rf) power applied in the high harmonic fast wave (HHFW) regime. HHFW heating and current drive differs from conventional fast wave current drive in that, although the frequency of operation (30-40 MHz) is in the range of conventional tokamak experiments, ω_rf ~ 10-20 Ω_ci due to the low magnetic field (0.35 T). Strong absorption (100% per pass) is ensured by the high plasma beta. Here we present numerical modelling of HHFW heating and current drive in NSTX using the PICES, FISIC, and METS95 codes. Preliminary designs for the NSTX HHFW antenna and matching system are also presented, along with analysis of the launched antenna wavenumber spectrum using the RANT3D code.

  17. Full-color holographic 3D printer

    NASA Astrophysics Data System (ADS)

    Takano, Masami; Shigeta, Hiroaki; Nishihara, Takashi; Yamaguchi, Masahiro; Takahashi, Susumu; Ohyama, Nagaaki; Kobayashi, Akihiko; Iwata, Fujio

    2003-05-01

    A holographic 3D printer is a system that produces a direct hologram with full-parallax information using the 3-dimensional data of a subject from a computer. In this paper, we present a proposal for the reproduction of full-color images with the holographic 3D printer. In order to realize the 3-dimensional color image, we selected the 3 laser wavelength colors of red (λ=633nm), green (λ=533nm), and blue (λ=442nm), and we built a one-step optical system using a projection system and a liquid crystal display. The 3-dimensional color image is obtained by synthesizing in a 2D array the multiple exposure with these 3 wavelengths made on each 250mm elementary hologram, and moving recording medium on a x-y stage. For the natural color reproduction in the holographic 3D printer, we take the approach of the digital processing technique based on the color management technology. The matching between the input and output colors is performed by investigating first, the relation between the gray level transmittance of the LCD and the diffraction efficiency of the hologram and second, by measuring the color displayed by the hologram to establish a correlation. In our first experimental results a non-linear functional relation for single and multiple exposure of the three components were found. These results are the first step in the realization of a natural color 3D image produced by the holographic color 3D printer.

  18. 3D bioprinting for engineering complex tissues.

    PubMed

    Mandrycky, Christian; Wang, Zongjie; Kim, Keekyoung; Kim, Deok-Ho

    2016-01-01

    Bioprinting is a 3D fabrication technology used to precisely dispense cell-laden biomaterials for the construction of complex 3D functional living tissues or artificial organs. While still in its early stages, bioprinting strategies have demonstrated their potential use in regenerative medicine to generate a variety of transplantable tissues, including skin, cartilage, and bone. However, current bioprinting approaches still have technical challenges in terms of high-resolution cell deposition, controlled cell distributions, vascularization, and innervation within complex 3D tissues. While no one-size-fits-all approach to bioprinting has emerged, it remains an on-demand, versatile fabrication technique that may address the growing organ shortage as well as provide a high-throughput method for cell patterning at the micrometer scale for broad biomedical engineering applications. In this review, we introduce the basic principles, materials, integration strategies and applications of bioprinting. We also discuss the recent developments, current challenges and future prospects of 3D bioprinting for engineering complex tissues. Combined with recent advances in human pluripotent stem cell technologies, 3D-bioprinted tissue models could serve as an enabling platform for high-throughput predictive drug screening and more effective regenerative therapies.

  19. 3D optical measuring technologies and systems

    NASA Astrophysics Data System (ADS)

    Chugui, Yuri V.

    2005-02-01

    The results of the R & D activity of TDI SIE SB RAS in the field of the 3D optical measuring technologies and systems for noncontact 3D optical dimensional inspection applied to atomic and railway industry safety problems are presented. This activity includes investigations of diffraction phenomena on some 3D objects, using the original constructive calculation method. The efficient algorithms for precise determining the transverse and longitudinal sizes of 3D objects of constant thickness by diffraction method, peculiarities on formation of the shadow and images of the typical elements of the extended objects were suggested. Ensuring the safety of nuclear reactors and running trains as well as their high exploitation reliability requires a 100% noncontact precise inspection of geometrical parameters of their components. To solve this problem we have developed methods and produced the technical vision measuring systems LMM, CONTROL, PROFIL, and technologies for noncontact 3D dimensional inspection of grid spacers and fuel elements for the nuclear reactor VVER-1000 and VVER-440, as well as automatic laser diagnostic COMPLEX for noncontact inspection of geometric parameters of running freight car wheel pairs. The performances of these systems and the results of industrial testing are presented and discussed. The created devices are in pilot operation at Atomic and Railway Companies.

  20. Magnetic Properties of 3D Printed Toroids

    NASA Astrophysics Data System (ADS)

    Bollig, Lindsey; Otto, Austin; Hilpisch, Peter; Mowry, Greg; Nelson-Cheeseman, Brittany; Renewable Energy; Alternatives Lab (REAL) Team

    Transformers are ubiquitous in electronics today. Although toroidal geometries perform most efficiently, transformers are traditionally made with rectangular cross-sections due to the lower manufacturing costs. Additive manufacturing techniques (3D printing) can easily achieve toroidal geometries by building up a part through a series of 2D layers. To get strong magnetic properties in a 3D printed transformer, a composite filament is used containing Fe dispersed in a polymer matrix. How the resulting 3D printed toroid responds to a magnetic field depends on two structural factors of the printed 2D layers: fill factor (planar density) and fill pattern. In this work, we investigate how the fill factor and fill pattern affect the magnetic properties of 3D printed toroids. The magnetic properties of the printed toroids are measured by a custom circuit that produces a hysteresis loop for each toroid. Toroids with various fill factors and fill patterns are compared to determine how these two factors can affect the magnetic field the toroid can produce. These 3D printed toroids can be used for numerous applications in order to increase the efficiency of transformers by making it possible for manufacturers to make a toroidal geometry.