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Sample records for single rotating slanting

  1. Reconstructing uniformly attenuated rotating slant-hole SPECT projection data using the DBH method

    International Nuclear Information System (INIS)

    Huang Qiu; Gullberg, Grant T; Xu Jingyan; Tsui, Benjamin M W

    2009-01-01

    This work applies a previously developed analytical algorithm to the reconstruction problem in a rotating multi-segment slant-hole (RMSSH) SPECT system. The RMSSH collimator has greater detection efficiency than the parallel-hole collimator with comparable spatial resolution at the expense of limited common volume-of-view (CVOV) and is therefore suitable for detecting low-contrast lesions in breast, cardiac and brain imaging. The absorption of gamma photons in both the human breast and brain can be assu- med to follow an exponential rule with a constant attenuation coefficient. In this work, the RMSSH SPECT data of a digital NCAT phantom with breast attachment are modeled as the uniformly attenuated Radon transform of the activity distribution. These data are reconstructed using an analytical algorithm called the DBH method, which is an acronym for the procedure of differentiation backprojection followed by a finite weighted inverse Hilbert transform. The projection data are first differentiated along a specific direction in the projection space and then backprojected to the image space. The result from this first step is equal to a one-dimensional finite weighted Hilbert transform of the object; this transform is then numerically inverted to obtain the reconstructed image. With the limited CVOV of the RMSSH collimator, the detector captures gamma photon emissions from the breast and from parts of the torso. The simulation results show that the DBH method is capable of exactly reconstructing the activity within a well-defined region-of-interest (ROI) within the breast if the activity is confined to the breast or if the activity outside the CVOV is uniformly attenuated for each measured projection, while a conventional filtered backprojection algorithm only reconstructs the high frequency components of the activity function in the same geometry.

  2. Rotary slanted single wire CTA – a useful tool for 3D flows investigations

    Directory of Open Access Journals (Sweden)

    Jonáš P.

    2013-04-01

    Full Text Available The procedure is described of experimental investigation of a statistically stationary generally nonisothermal 3D flow by means of a constant temperature anemometer (CTA using single slanted heated wire, rotary round the fixed axis. The principle of this procedure is quite clear. The change of the heated wire temperature modifies ratio of CTA sensitivities to temperature and velocity fluctuations. Turning the heated wire through a proper angle changes the sensitivity to components of the instantaneous velocity vector. Some recommendations are presented based on long time experiences, e.g. on the choice of probe, on the probe calibration, to the measurement organization and to the evaluation of results.

  3. Chiral Metamaterials of Plasmonic Slanted Nanoapertures with Symmetry Breaking.

    Science.gov (United States)

    Chen, Yang; Gao, Jie; Yang, Xiaodong

    2018-01-10

    We propose a universal design scheme for a new type of chiral metamaterials based on plasmonic slanted nanoapertures simply milled in a single metal layer. Strong optical chirality is introduced by tilting nanoapertures with almost arbitrary shape along a certain direction to break all the mirror symmetries. As a typical example, chiral metamaterial based on slanted split-ring apertures is demonstrated with giant circular dichroism in transmission (CDT) over 78% at 760 nm. We reveal that the high CDT originates from the circularly dichroic mode coupling process in the slanted nanoapertures induced by spin-dependent field overlap conditions. Furthermore, tunable CDT is presented through the in-plane rotation of nanoapertures to form chiral images with controllable image contrast. Besides, chiral metamaterials with slanted nanoapertures of two other shapes including L-shaped aperture and rectangular aperture are also presented with large circular dichroism. We envision that our demonstrated chiral metamaterials enable promising platforms for a variety of applications in nonlinear optics, chiral imaging and sensing, spectroscopy, and polarization manipulation.

  4. Actuator assembly including a single axis of rotation locking member

    Science.gov (United States)

    Quitmeyer, James N.; Benson, Dwayne M.; Geck, Kellan P.

    2009-12-08

    An actuator assembly including an actuator housing assembly and a single axis of rotation locking member fixedly attached to a portion of the actuator housing assembly and an external mounting structure. The single axis of rotation locking member restricting rotational movement of the actuator housing assembly about at least one axis. The single axis of rotation locking member is coupled at a first end to the actuator housing assembly about a Y axis and at a 90.degree. angle to an X and Z axis providing rotation of the actuator housing assembly about the Y axis. The single axis of rotation locking member is coupled at a second end to a mounting structure, and more particularly a mounting pin, about an X axis and at a 90.degree. angle to a Y and Z axis providing rotation of the actuator housing assembly about the X axis. The actuator assembly is thereby restricted from rotation about the Z axis.

  5. Manipulation of light using slanted layer photonic crystals in holographic gelatin emulsions

    Science.gov (United States)

    Yau, Suet Man; Hin Kok, Mang; Tam, Wing Yim

    2008-01-01

    We use slanted layer structures fabricated in holographic gelatin emulsions using a two-beam optical interference to bend light in the bandgap of the layer structures. We demonstrate that light in the visible range, incident normal to the holographic emulsion plate, can be bent so that it is trapped inside the gelatin emulsion by internal reflections and comes out at the edges of the plate using a single-slanted-layer structure. Furthermore, we show that using a double-slanted-layer structure, consisting of two single-slanted-layer structures arranged in a V-shaped configuration, light in the bandgap can make a U-turn inside the gelatin emulsion and come out of the emulsion like a reflection but with the beam displaced from the incident beam by the separation of the two slanted layers. The slanted layer structures may be applicable in steering light in optical circuits and couplers.

  6. Geometric Calibration and Image Reconstruction for a Segmented Slant-Hole Stationary Cardiac SPECT System.

    Science.gov (United States)

    Mao, Yanfei; Yu, Zhicong; Zeng, Gengsheng L

    2015-06-01

    A dedicated stationary cardiac single-photon emission computed tomography (SPECT) system with a novel segmented slant-hole collimator has been developed. The goal of this paper is to calibrate this new imaging geometry with a point source. Unlike the commercially available dedicated cardiac SPECT systems, which are specialized and can be used only to image the heart, our proposed cardiac system is based on a conventional SPECT system but with a segmented slant-hole collimator replacing the collimator. For a dual-head SPECT system, 2 segmented collimators, each with 7 sections, are arranged in an L-shaped configuration such that they can produce a complete cardiac SPECT image with only one gantry position. A calibration method was developed to estimate the geometric parameters of each collimator section as well as the detector rotation radius, under the assumption that the point source location is calculated using the central-section data. With a point source located off the rotation axis, geometric parameters for each collimator section can be estimated independently. The parameters estimated individually are further improved by a joint objective function that uses all collimator sections simultaneously and incorporates the collimator symmetry information. Estimation results and images reconstructed from estimated parameters are presented for both simulated and real data acquired from a prototype collimator. The calibration accuracy was validated by computer simulations with an error of about 0.1° for the slant angles and about 1 mm for the rotation radius. Reconstructions of a heart-insert phantom did not show any image artifacts of inaccurate geometric parameters. Compared with the detector's intrinsic resolution, the estimation error is small and can be ignored. Therefore, the accuracy of the calibration is sufficient for cardiac SPECT imaging. © 2015 by the Society of Nuclear Medicine and Molecular Imaging, Inc.

  7. Early dynamics of stereoscopic surface slant perception.

    Science.gov (United States)

    Caziot, Baptiste; Backus, Benjamin T; Lin, Esther

    2017-12-01

    Surface orientation is an important visual primitive that can be estimated from monocular or binocular (stereoscopic) signals. Changes in motor planning occur within about 200 ms after either type of signal is perturbed, but the time it takes for apparent (perceived) slant to develop from stereoscopic cues is not known. Apparent slant sometimes develops very slowly (Gillam, Chambers, & Russo, 1988; van Ee & Erkelens, 1996). However, these long durations could reflect the time it takes for the visual system to resolve conflicts between slant cues that inevitably specify different slants in laboratory displays (Allison & Howard, 2000). We used a speed-accuracy tradeoff analysis to measure the time it takes to discriminate slant, allowing us to report psychometric functions as a function of response time. Observers reported which side of a slanted surface was farther, with a temporal deadline for responding that varied block-to-block. Stereoscopic slant discrimination rose above chance starting at 200 ms after stimulus onset. Unexpectedly, observers discriminated slant from binocular disparity faster than texture, and for stereoscopic whole-field stimuli faster than stereoscopic slant contrast stimuli. However, performance after the initial deviation from chance increased more rapidly for slant-contrast stimuli than whole-field stimuli. Discrimination latencies were similar for slants about the horizontal and vertical axes, but performance increased faster for slants about the vertical axis. Finally, slant from vertical disparity was somewhat slower than slant from horizontal disparity, which may reflect cue conflict. These results demonstrate, in contradiction with the previous literature, that the perception of slant from disparity happens very quickly-in fact, more quickly than the perception of slant from texture-and in comparable time to the simple perception of brightness from luminance.

  8. Single Particle Orientation and Rotational Tracking (SPORT) in biophysical studies

    Science.gov (United States)

    Gu, Yan; Ha, Ji Won; Augspurger, Ashley E.; Chen, Kuangcai; Zhu, Shaobin; Fang, Ning

    2013-10-01

    The single particle orientation and rotational tracking (SPORT) techniques have seen rapid development in the past 5 years. Recent technical advances have greatly expanded the applicability of SPORT in biophysical studies. In this feature article, we survey the current development of SPORT and discuss its potential applications in biophysics, including cellular membrane processes and intracellular transport.The single particle orientation and rotational tracking (SPORT) techniques have seen rapid development in the past 5 years. Recent technical advances have greatly expanded the applicability of SPORT in biophysical studies. In this feature article, we survey the current development of SPORT and discuss its potential applications in biophysics, including cellular membrane processes and intracellular transport. Electronic supplementary information (ESI) available: Three supplementary movies and an experimental section. See DOI: 10.1039/c3nr02254d

  9. Opposed slant tube diabatic sorber

    Science.gov (United States)

    Erickson, Donald C.

    2004-01-20

    A sorber comprised of at least three concentric coils of tubing contained in a shell with a flow path for liquid sorbent in one direction, a flow path for heat transfer fluid which is in counter-current heat exchange relationship with sorbent flow, a sorbate vapor port in communication with at least one of sorbent inlet or exit ports, wherein each coil is coiled in opposite direction to those coils adjoining it, whereby the opposed slant tube configuration is achieved, with structure for flow modification in the core space inside the innermost coil.

  10. Study of a Microfluidic Chip Integrating Single Cell Trap and 3D Stable Rotation Manipulation

    Directory of Open Access Journals (Sweden)

    Liang Huang

    2016-08-01

    Full Text Available Single cell manipulation technology has been widely applied in biological fields, such as cell injection/enucleation, cell physiological measurement, and cell imaging. Recently, a biochip platform with a novel configuration of electrodes for cell 3D rotation has been successfully developed by generating rotating electric fields. However, the rotation platform still has two major shortcomings that need to be improved. The primary problem is that there is no on-chip module to facilitate the placement of a single cell into the rotation chamber, which causes very low efficiency in experiment to manually pipette single 10-micron-scale cells into rotation position. Secondly, the cell in the chamber may suffer from unstable rotation, which includes gravity-induced sinking down to the chamber bottom or electric-force-induced on-plane movement. To solve the two problems, in this paper we propose a new microfluidic chip with manipulation capabilities of single cell trap and single cell 3D stable rotation, both on one chip. The new microfluidic chip consists of two parts. The top capture part is based on the least flow resistance principle and is used to capture a single cell and to transport it to the rotation chamber. The bottom rotation part is based on dielectrophoresis (DEP and is used to 3D rotate the single cell in the rotation chamber with enhanced stability. The two parts are aligned and bonded together to form closed channels for microfluidic handling. Using COMSOL simulation and preliminary experiments, we have verified, in principle, the concept of on-chip single cell traps and 3D stable rotation, and identified key parameters for chip structures, microfluidic handling, and electrode configurations. The work has laid a solid foundation for on-going chip fabrication and experiment validation.

  11. The role of (micro)saccades and blinks in perceptual bi-stability from slant rivalry.

    Science.gov (United States)

    van Dam, Loes C J; van Ee, Raymond

    2005-08-01

    We exposed the visual system to an ambiguous 3D slant rivalry stimulus consisting of a grid for which monocular (perspective) and binocular (disparity) cues independently specified a slant about a horizontal axis. When those cues specified similar slants, observers perceived a single slant. When the difference between the specified slants was large, observers alternatively perceived a perspective- or a disparity-dominated slant. Eye movement measurements revealed that there was no positive correlation between a perceptual flip and both saccades (microsaccades as well as larger saccades) and blinks that occurred prior to a perceptual flip. We also found that changes in horizontal vergence were not responsible for perceptual flips. Thus, eye movements were not essential to flip from one percept to the other. After the moment of a perceptual flip the occurrence probabilities of both saccades and blinks were reduced. The reduced probability of saccades mainly occurred for larger voluntary saccades, rather than for involuntary microsaccades. We suggest that the reduced probability of voluntary saccades reflects a reset of saccade planning.

  12. Ultra-thin, single-layer polarization rotator

    Energy Technology Data Exchange (ETDEWEB)

    Son, T. V.; Truong, V. V., E-mail: Truong.Vo-Van@Concordia.Ca [Department of Physics, Concordia University, Montreal, Quebec, H4B 1R6 (Canada); Do, P. A.; Haché, A. [Département de Physique et d’Astronomie, Université de Moncton, Moncton, New Brunswick, E1A 3E9 (Canada)

    2016-08-15

    We demonstrate light polarization control over a broad spectral range by a uniform layer of vanadium dioxide as it undergoes a phase transition from insulator to metal. Changes in refractive indices create unequal phase shifts on s- and p-polarization components of incident light, and rotation of linear polarization shows intensity modulation by a factor of 10{sup 3} when transmitted through polarizers. This makes possible polarization rotation devices as thin as 50 nm that would be activated thermally, optically or electrically.

  13. Segmented slant hole collimator for stationary cardiac SPECT: Monte Carlo simulations.

    Science.gov (United States)

    Mao, Yanfei; Yu, Zhicong; Zeng, Gengsheng L

    2015-09-01

    This work is a preliminary study of a stationary cardiac SPECT system. The goal of this research is to propose a stationary cardiac SPECT system using segmented slant-hole collimators and to perform computer simulations to test the feasibility. Compared to the rotational SPECT, a stationary system has a benefit of acquiring temporally consistent projections. The most challenging issue in building a stationary system is to provide sufficient projection view-angles. A GATE (GEANT4 application for tomographic emission) Monte Carlo model was developed to simulate a two-detector stationary cardiac SPECT that uses segmented slant-hole collimators. Each detector contains seven segmented slant-hole sections that slant to a common volume at the rotation center. Consequently, 14 view-angles over 180° were acquired without any gantry rotation. The NCAT phantom was used for data generation and a tailored maximum-likelihood expectation-maximization algorithm was used for image reconstruction. Effects of limited number of view-angles and data truncation were carefully evaluated in the paper. Simulation results indicated that the proposed segmented slant-hole stationary cardiac SPECT system is able to acquire sufficient data for cardiac imaging without a loss of image quality, even when the uptakes in the liver and kidneys are high. Seven views are acquired simultaneously at each detector, leading to 5-fold sensitivity gain over the conventional dual-head system at the same total acquisition time, which in turn increases the signal-to-noise ratio by 19%. The segmented slant-hole SPECT system also showed a good performance in lesion detection. In our prototype system, a short hole-length was used to reduce the dead zone between neighboring collimator segments. The measured sensitivity gain is about 17-fold over the conventional dual-head system. The gate Monte Carlo simulations confirm the feasibility of the proposed stationary cardiac SPECT system with segmented slant

  14. Ultra-thin, single-layer polarization rotator

    Directory of Open Access Journals (Sweden)

    T. V. Son

    2016-08-01

    Full Text Available We demonstrate light polarization control over a broad spectral range by a uniform layer of vanadium dioxide as it undergoes a phase transition from insulator to metal. Changes in refractive indices create unequal phase shifts on s- and p-polarization components of incident light, and rotation of linear polarization shows intensity modulation by a factor of 103 when transmitted through polarizers. This makes possible polarization rotation devices as thin as 50 nm that would be activated thermally, optically or electrically.

  15. Modelling unidirectional liquid spreading on slanted microposts

    DEFF Research Database (Denmark)

    Cavalli, Andrea; Blow, Matthew L.; Yeomans, Julia M.

    2013-01-01

    A lattice Boltzmann algorithm is used to simulate the slow spreading of drops on a surface patterned with slanted micro-posts. Gibb's pinning of the interface on the sides or top of the posts leads to unidirectional spreading over a wide range of contact angles and inclination angles of the posts...

  16. Slant Riemannian maps from almost hermitian manifolds | Sahin ...

    African Journals Online (AJOL)

    As a generalization of holomorphic submersions, anti-invariant submersions and slant submersions, we introduce slant Riemannian maps from almost Hermitian manifolds to Riemannian manifolds. We give examples, obtain the existence conditions of slant Riemannian maps and investigate harmonicity of such maps.

  17. Integration of texture and disparity cues to surface slant in dorsal visual cortex.

    Science.gov (United States)

    Murphy, Aidan P; Ban, Hiroshi; Welchman, Andrew E

    2013-07-01

    Reliable estimation of three-dimensional (3D) surface orientation is critical for recognizing and interacting with complex 3D objects in our environment. Human observers maximize the reliability of their estimates of surface slant by integrating multiple depth cues. Texture and binocular disparity are two such cues, but they are qualitatively very different. Existing evidence suggests that representations of surface tilt from each of these cues coincide at the single-neuron level in higher cortical areas. However, the cortical circuits responsible for 1) integration of such qualitatively distinct cues and 2) encoding the slant component of surface orientation have not been assessed. We tested for cortical responses related to slanted plane stimuli that were defined independently by texture, disparity, and combinations of these two cues. We analyzed the discriminability of functional MRI responses to two slant angles using multivariate pattern classification. Responses in visual area V3B/KO to stimuli containing congruent cues were more discriminable than those elicited by single cues, in line with predictions based on the fusion of slant estimates from component cues. This improvement was specific to congruent combinations of cues: incongruent cues yielded lower decoding accuracies, which suggests the robust use of individual cues in cases of large cue conflicts. These data suggest that area V3B/KO is intricately involved in the integration of qualitatively dissimilar depth cues.

  18. Apparatus and method for variable angle slant hole collimator

    Science.gov (United States)

    Lee, Seung Joon; Kross, Brian J.; McKisson, John E.

    2017-07-18

    A variable angle slant hole (VASH) collimator for providing collimation of high energy photons such as gamma rays during radiological imaging of humans. The VASH collimator includes a stack of multiple collimator leaves and a means of quickly aligning each leaf to provide various projection angles. Rather than rotate the detector around the subject, the VASH collimator enables the detector to remain stationary while the projection angle of the collimator is varied for tomographic acquisition. High collimator efficiency is achieved by maintaining the leaves in accurate alignment through the various projection angles. Individual leaves include unique angled cuts to maintain a precise target collimation angle. Matching wedge blocks driven by two actuators with twin-lead screws accurately position each leaf in the stack resulting in the precise target collimation angle. A computer interface with the actuators enables precise control of the projection angle of the collimator.

  19. Rotation of a single molecule within a supramolecular bearing

    DEFF Research Database (Denmark)

    Gimzewski, J.K.; Joachim, C.; Schlittler, R.R.

    1998-01-01

    Experimental visualization and verification of a single-molecule rotor operating within a supramolecular bearing is reported. Using a scanning tunneling microscope, single molecules were observed to exist in one of two spatially defined states Laterally separated by 0.26 nanometers. One...

  20. A rotator for single-crystal neutron diffraction at high pressure.

    Science.gov (United States)

    Fang, J; Bull, C L; Hamidov, H; Loveday, J S; Gutmann, M J; Nelmes, R J; Kamenev, K V

    2010-11-01

    We present a modified Paris-Edinburgh press which allows rotation of the anvils and the sample under applied load. The device is designed to overcome the problem of having large segments of reciprocal space obscured by the tie rods of the press during single-crystal neutron-scattering experiments. The modified press features custom designed hydraulic bearings and provides controls for precision rotation and positioning. The advantages of using the device for increasing the number of measurable reflections are illustrated with the results of neutron-diffraction experiments on a single crystal of germanium rotated under a load of 70 tonnes.

  1. A variable angle slant-hole collimator

    International Nuclear Information System (INIS)

    Moore, R.H.; Alpert, N.M.; Strauss, H.W.

    1983-01-01

    A variable-angle slant-hole (VASH) collimator was constructed to show the feasibility of using multiple sliding plates to achieve a range of collimator channel inclinations. One hundred and sixty tungsten plates, 0.125 mm thick and 14 cm square, were photoetched to produce 3025 1.5-mm2 holes in each plate, separated by 0.8-mm septa. Along with the collimator holes, registration holes and positioning grooves were also etched. The plates were placed in a holder and stacked to form a collimator 2.0 cm high. The holder permitted the plates to be sheared to achieve viewing angles from 0 to 40 degrees from the vertical. Resolution and sensitivity were determined both across and along the shear directions. Resolution of a thin /sup 99m/Tc source, 1.24 mm diam and 7 cm long, located 5 cm from the collimator face in air, was 1.1 cm FWHM at 0 degree shear and remained unchanged with increasing slant. The resolution was similar both across and along the shear plane. Sensitivity was determined with a point source placed 7 cm from the collimator face. At 0 degree slant the sensitivity was 169 cps/MBq (6.24 csp/mu Ci). A general all purpose (GAP) collimator had a FWHM of 1 cm for the line source in air at 5 cm, and a sensitivity of 205 cps/MBq (7.58 cps/mu Ci) for the point source at 7 cm. The data suggest that a variable-angle slant-hole collimator can be constructed of laminated plates

  2. RETRACTED: Quantum key distribution without sharing reference frame using single photon rotational-invariant subspace

    Science.gov (United States)

    Chen, Dong-Xu; Liu, Rui-Feng; Zhang, Pei; Li, Hong-Rong; Gao, Hong; Li, Fu-Li

    2013-11-01

    We report an experimental proposal of quantum key distribution without sharing reference frame by using single photon rotational-invariant subspace. The rotational-invariant subspace is achieved by taking advantage of photon's spin-orbital composite states. Our scheme is simple and can be developed as a compact QKD system under current technology. Earth-to-satellite QKD is an emerging scenario that will benefit from our protocol.

  3. Slant rigs offer big payoffs in shallow drilling

    International Nuclear Information System (INIS)

    Smith, J.; Edwards, B.

    1992-01-01

    Slant hole drilling technology can result in considerable savings over conventionally drilled deviated holes because mud motors and deviation control with measurement while drilling tools are usually unnecessary. The benefits of using slant hole rigs for development drilling improve after the bit walk tendencies and the correct bottom hole assemblies have been determined for a particular area. This article discusses three recent drilling operations that successfully used slant drilling technology on land-based projects: drilling for heavy oil in Alberta, drilling for gas in Alberta, and drilling a river crossing for a gas pipeline in British Columbia. These examples demonstrate the flexibility of slant drilling technology

  4. Functional and magnetic resonance imaging evaluation after single-tendon rotator cuff reconstruction

    DEFF Research Database (Denmark)

    Knudsen, H B; Gelineck, J; Søjbjerg, Jens Ole

    1999-01-01

    The aim of this study was to investigate tendon integrity after surgical repair of single-tendon rotator cuff lesions. In 31 patients, 31 single-tendon repairs were evaluated. Thirty-one patients were available for clinical assessment and magnetic resonance imaging (MRI) at follow-up. A standard...... series of MR images was obtained for each. The results of functional assessment were scored according to the system of Constant. According to MRI evaluation, 21 (68%) patients had an intact or thinned rotator cuff and 10 (32%) had recurrence of a full-thickness cuff defect at follow-up. Patients...... with an intact or thinned rotator cuff had a median Constant score of 75.5 points; patients with a full-thickness cuff defect had a median score of 62 points. There was no correlation between tendon integrity on postoperative MR images and functional outcome. Patients with intact or thinned cuffs did not have...

  5. Simultaneous SU(2) rotations on multiple quantum dot exciton qubits using a single shaped pulse

    Science.gov (United States)

    Mathew, Reuble; Yang, Hong Yi Shi; Hall, Kimberley C.

    2015-10-01

    Recent experimental demonstration of a parallel (π ,2 π ) single qubit rotation on excitons in two distant quantum dots [Nano Lett. 13, 4666 (2013), 10.1021/nl4018176] is extended in numerical simulations to the design of pulses for more general quantum state control, demonstrating the feasibility of full SU(2) rotations of each exciton qubit. Our results show that simultaneous high-fidelity quantum control is achievable within the experimentally accessible parameter space for commercial Fourier-domain pulse shaping systems. The identification of a threshold of distinguishability for the two quantum dots (QDs) for achieving high-fidelity parallel rotations, corresponding to a difference in transition energies of ˜0.25 meV , points to the possibility of controlling more than 10 QDs with a single shaped optical pulse.

  6. Principles and biophysical applications of single particle super-localization and rotational tracking

    Energy Technology Data Exchange (ETDEWEB)

    Gu, Yan [Iowa State Univ., Ames, IA (United States)

    2013-01-01

    While conventional Single Particle Tracking (SPT) techniques acquire 2D or 3D trajectories of particle probes, we have developed Single Particle Orientation and Rotational Tracking (SPORT) techniques to extract orientation and rotational information. Combined with DIC microscopy, the SPORT technique has been applied in biophysical studies, including membrane diffusion and intracellular transport. The rotational dynamics of nanoparticle vectors on live cell membranes was recorded and its influence on the fate of these nanoparticle vectors was elucidated. The rotational motions of gold nanorods with various surface modifiers were tracked continuously at a temporal resolution of 5 ms under a DIC microscope. We found that the rotational behaviors of gold nanorod vectors are strongly related to their surface charge, specific surface functional groups, and the availability of receptors on cell membranes. The study of rotational Brownian motion of nanoparticles on cell membranes will lead to a better understanding of the mechanisms of drug delivery and provide guidance in designing surface modification strategies for drug delivery vectors under various circumstances. To characterize the rotation mode of surface functionalized gold nanorods on cell membranes, the SPORT technique is combined with the correlation analysis of the bright and dark DIC intensities. The unique capabilities of visualizing and understanding rotational motions of functionalized nanoparticles on live cell membranes allow us to correlate rotational and translational dynamics in unprecedented detail and provide new insights for complex membrane processes, including electrostatic interactions, ligand-receptor binding, and lateral (confined and hopping) diffusion of membrane receptors. Surface-functionalized nanoparticles interact with the membrane in fundamentally different ways and exhibit distinct rotational modes. The early events of particle-membrane approach and attachment are directly visualized

  7. PI and repetitive control for single phase inverter based on virtual rotating coordinate system

    Science.gov (United States)

    Li, Mengqi; Tong, Yibin; Jiang, Jiuchun; Liang, Jiangang

    2018-03-01

    Microgrid technology developed rapidly and nonlinear loads were connected increasingly. A new control strategy was proposed for single phase inverter when connected nonlinear loads under island condition. PI and repetitive compound controller was realized under synchronous rotating coordinate system and acquired high quality sinusoidal voltage output without voltage spike when loads step changed. Validity and correctness were verified by simulation using MATLAB/Simulink.

  8. Beyond Dualism and Monism: Bergson's Slanted Being

    Directory of Open Access Journals (Sweden)

    Messay Kebede

    2016-12-01

    Full Text Available There is an old but still unresolved debate pertaining to the question of Bergsonian monism or dualism.  Scholars who think that Bergson is ultimately monist clash with those who claim that he has consistently maintained a dualist position. Others speak of contradiction and point out his failure to reconcile dualism with monism. What feeds on the debate is Bergson’s undeniable change of direction: while his first book is flagrantly dualist, his second book takes a sharp turn toward monism. Without denying the intricacy generated by the change of direction, this paper argues that the originality of his position is overlooked every time that the problem is presented in terms of Bergson being dualist or monist. Notably, it contends that Bergson’s third book, Creative Evolution, overcomes both dualism and monism by removing their contradiction through a durational or slanted approach to Being.

  9. Slant-tilt: the visual encoding of surface orientation.

    Science.gov (United States)

    Stevens, K A

    1983-01-01

    A specific form for the internal representation of local surface orientation is proposed, which is similar to Gibson's (1950) "amount and direction of slant". Slant amount is usually quantified by the angle sigma between the surface normal and the line of sight (0 degrees less than or equal to sigma less than or equal to 90 degrees). Slant direction corresponds to the direction of the gradient of distance from the viewer to the surface, and may be defined by the image direction tau to which the surface normal would project (0 degrees less than or equal to tau less than or equal to 360 degrees). Since the direction of slant is specified by the tilt of the projected surface normal, it is referred to as surface tilt (Stevens, 1979; Marr, 1982). The two degrees of freedom of orientation are therefore quantified by slant, an angle measured perpendicular to the image plane, and tilt, an angle measured in the image plane. The slant-tilt form provides several computational advantages relative to some other proposals and is consistent with various psychological phenomena. Slant might be encoded by various means, e.g. by the cosine of the angle, by the tangent, or linearly by the angle itself. Experimental results are reported that suggest that slant is encoded by an internal parameter that varies linearly with slant angle, with resolution of roughly one part in 100. Thus we propose that surface orientation is encoded in human vision by two quantities, one varying linearly with slant angle, the other varying linearly with tilt angle.

  10. Proposal for a rotating analyser single crystal spectrometer at a pulsed neutron source

    International Nuclear Information System (INIS)

    Geick, R.; Tietze, H.

    1986-01-01

    We propose a new type of crystal analyser time-of-flight spectrometer for elastic and inelastic single crystal measurements at a pulsed neutron source. Using a nonuniformly rotating analyser, a flexibility of the spectrometer is achieved intermediate between that of the crystal analyser time-of-flight spectrometers like MAX and Constant-Q and the triple axis spectrometer. In detail, we discuss constant-(h/2π)ω and constant-(Q/vertical strokeQvertical stroke) scans for our spectrometer and the nonuniform rotation of the analyser necessary for these special scans. (orig.)

  11. Astigmatic single photon emission computed tomography imaging with a displaced center of rotation

    International Nuclear Information System (INIS)

    Wang, H.; Smith, M.F.; Stone, C.D.; Jaszczak, R.J.

    1998-01-01

    A filtered backprojection algorithm is developed for single photon emission computed tomography (SPECT) imaging with an astigmatic collimator having a displaced center of rotation. The astigmatic collimator has two perpendicular focal lines, one that is parallel to the axis of rotation of the gamma camera and one that is perpendicular to this axis. Using SPECT simulations of projection data from a hot rod phantom and point source arrays, it is found that a lack of incorporation of the mechanical shift in the reconstruction algorithm causes errors and artifacts in reconstructed SPECT images. The collimator and acquisition parameters in the astigmatic reconstruction formula, which include focal lengths, radius of rotation, and mechanical shifts, are often partly unknown and can be determined using the projections of a point source at various projection angles. The accurate determination of these parameters by a least squares fitting technique using projection data from numerically simulated SPECT acquisitions is studied. These studies show that the accuracy of parameter determination is improved as the distance between the point source and the axis of rotation of the gamma camera is increased. The focal length to the focal line perpendicular to the axis of rotation is determined more accurately than the focal length to the focal line parallel to this axis. copyright 1998 American Association of Physicists in Medicine

  12. Single-Molecule Rotational Switch on a Dangling Bond Dimer Bearing.

    Science.gov (United States)

    Godlewski, Szymon; Kawai, Hiroyo; Kolmer, Marek; Zuzak, Rafał; Echavarren, Antonio M; Joachim, Christian; Szymonski, Marek; Saeys, Mark

    2016-09-27

    One of the key challenges in the construction of atomic-scale circuits and molecular machines is to design molecular rotors and switches by controlling the linear or rotational movement of a molecule while preserving its intrinsic electronic properties. Here, we demonstrate both the continuous rotational switching and the controlled step-by-step single switching of a trinaphthylene molecule adsorbed on a dangling bond dimer created on a hydrogen-passivated Ge(001):H surface. The molecular switch is on-surface assembled when the covalent bonds between the molecule and the dangling bond dimer are controllably broken, and the molecule is attached to the dimer by long-range van der Waals interactions. In this configuration, the molecule retains its intrinsic electronic properties, as confirmed by combined scanning tunneling microscopy/spectroscopy (STM/STS) measurements, density functional theory calculations, and advanced STM image calculations. Continuous switching of the molecule is initiated by vibronic excitations when the electrons are tunneling through the lowest unoccupied molecular orbital state of the molecule. The switching path is a combination of a sliding and rotation motion over the dangling bond dimer pivot. By carefully selecting the STM conditions, control over discrete single switching events is also achieved. Combined with the ability to create dangling bond dimers with atomic precision, the controlled rotational molecular switch is expected to be a crucial building block for more complex surface atomic-scale devices.

  13. Trapping, manipulation and rapid rotation of NBD-C8 fluorescent single microcrystals in optical tweezers

    International Nuclear Information System (INIS)

    GALAUP, Jean-Pierre; RODRIGUEZ-OTAZO, Mariela; AUGIER-CALDERIN, Angel; LAMERE; Jean-Francois; FERY-FORGUES, Suzanne

    2009-01-01

    We have built an optical tweezers experiment based on an inverted microscope to trap and manipulate single crystals of micro or sub-micrometer size made from fluorescent molecules of 4-octylamino-7-nitrobenzoxadiazole (NBD-C8). These single crystals have parallelepiped shapes and exhibit birefringence properties evidenced through optical experiments between crossed polarizers in a polarizing microscope. The crystals are uniaxial with their optical axis oriented along their largest dimension. Trapped in the optical trap, the organic micro-crystals are oriented in such a way that their long axis is along the direction of the beam propagation, and their short axis follows the direction of the linear polarization. Therefore, with linearly polarized light, simply rotating the light polarization can orient the crystal. When using circularly or only elliptically polarized light, the crystal can spontaneously rotate and reach rotation speed of several hundreds of turns per second. A surprising result has been observed: when the incident power is growing up, the rotation speed increases to reach a maximum value and then decreases even when the power is still growing up. Moreover, this evolution is irreversible. Different possible explanations can be considered. The development of a 3D control of the crystals by dynamical holography using liquid crystal spatial modulators will be presented and discussed on the basis of the most recent results obtained. (Author)

  14. Large rotating magnetocaloric effect in ErAlO3 single crystal

    Directory of Open Access Journals (Sweden)

    X. Q. Zhang

    2017-05-01

    Full Text Available Magnetic and magnetocaloric properties of ErAlO3 single crystal were investigated. Magnetization of ErAlO3 shows obvious anisotropy when magnetic field is applied along the a, b and c axes, which leads to large anisotropic magnetic entropy change. In particular, large rotating field entropy change from the b to c axis within the bc plane is obtained and reaches 9.7 J/kg K at 14 K in a field of 5 T. This suggests the possibility of using ErAlO3 single crystal for magnetic refrigerators by rotating its magnetization vector rather than moving it in and out of the magnet.

  15. Debris Evaluation after Root Canal Shaping with Rotating and Reciprocating Single-File Systems

    Directory of Open Access Journals (Sweden)

    Alberto Dagna

    2016-10-01

    Full Text Available This study evaluated the root canal dentine surface by scanning electron microscope (SEM after shaping with two reciprocating single-file NiTi systems and two rotating single-file NiTi systems, in order to verify the presence/absence of the smear layer and the presence/absence of open tubules along the walls of each sample; Forty-eight single-rooted teeth were divided into four groups and shaped with OneShape (OS, F6 SkyTaper (F6, WaveOne (WO and Reciproc and irrigated using 5.25% NaOCl and 17% EDTA. Root canal walls were analyzed by SEM at a standard magnification of 2500×. The presence/absence of the smear layer and the presence/absence of open tubules at the coronal, middle, and apical third of each canal were estimated using a five-step scale for scores. Numeric data were analyzed using Kruskal-Wallis and Mann-Whitney U statistical tests and significance was predetermined at P < 0.05; The Kruskal-Wallis ANOVA for debris score showed significant differences among the NiTi systems (P < 0.05. The Mann-Whitney test confirmed that reciprocating systems presented significantly higher score values than rotating files. The same results were assessed considering the smear layer scores. ANOVA confirmed that the apical third of the canal maintained a higher quantity of debris and smear layer after preparation of all the samples; Single-use NiTi systems used in continuous rotation appeared to be more effective than reciprocating instruments in leaving clean walls. The reciprocating systems produced more debris and smear layer than rotating instruments.

  16. Antisolar differential rotation with surface lithium enrichment on the single K-giant V1192 Orionis

    Science.gov (United States)

    Kővári, Zs.; Strassmeier, K. G.; Carroll, T. A.; Oláh, K.; Kriskovics, L.; Kővári, E.; Kovács, O.; Vida, K.; Granzer, T.; Weber, M.

    2017-10-01

    Context. Stars with about 1-2 solar masses at the red giant branch (RGB) represent an intriguing period of stellar evolution, I.e. when the convective envelope interacts with the fast-rotating core. During these mixing episodes freshly synthesized lithium can come up to the stellar surface along with high angular momentum material. This high angular momentum may alter the surface rotation pattern. Aims: The single rapidly rotating K-giant V1192 Ori is revisited to determine its surface differential rotation, lithium abundance, and basic stellar properties such as a precise rotation period. The aim is to independently verify the antisolar differential rotation of the star and possibly find a connection to the surface lithium abundance. Methods: We applied time-series Doppler imaging to a new multi-epoch data set. Altogether we reconstructed 11 Doppler images from spectroscopic data collected with the STELLA robotic telescope between 2007-2016. We used our inversion code iMap to reconstruct all stellar surface maps. We extracted the differential rotation from these images by tracing systematic spot migration as a function of stellar latitude from consecutive image cross-correlations. Results: The position of V1192 Ori in the Hertzsprung-Russell diagram suggests that the star is in the helium core-burning phase just leaving the RGB bump. We measure A(Li)NLTE = 1.27, I.e. a value close to the anticipated transition value of 1.5 from Li-normal to Li-rich giants. Doppler images reveal extended dark areas arranged quasi-evenly along an equatorial belt. No cool polar spot is found during the investigated epoch. Spot displacements clearly suggest antisolar surface differential rotation with α = - 0.11 ± 0.02 shear coefficient. Conclusions: The surface Li enrichment and the peculiar surface rotation pattern may indicate a common origin. Based on data obtained with the STELLA robotic observatory in Tenerife, an AIP facility jointly operated by AIP and IAC.

  17. Single port intra-gastric full thickness resection: Using "Rotation and Revolution Single Instrument Tie (RRSIT)".

    Science.gov (United States)

    Kim, Ho Goon; Ryu, Seong Yeob; Kim, Dong Yi

    2014-09-01

    Recently, minimize incisions has led to a reduction in the number of ports, and has led to transumbilical single-port surgery. We evaluated the treatment result of single-port, intragastric, full thickness resections for gastric SMTs. In addition, we introduce a novel intracorporeal knot tying method. From August 2010 to March 2011, five patients underwent single-port intragastric, full thickness gastric wedge resections. After performing a gastrostomy, a single port was inserted into the stomach. After full thickness resection, the defect in the gastric wall was sutured by full thickness interrupted suture and a new knot tying technique. The mean operative time was 129 ± 21.0 min and the mean mass size was 3.0±0.6 cm. There were two very low-risk GISTs, 2 leiomyomas, and 1 carcinoid. The post-operative course was uneventful in all patients. The mean hospital stay was 7.2±1.2 days. Single-port intra-gastric full thickness resection with novel intracorporeal knot tying method is feasible and safe. novel intracorporeal knot tying method is a very useful knot tying method. We expect the application of novel intracorporeal knot tying method to be diverse and broad.

  18. Magnetocrystalline anisotropy of cementite pseudo single crystal fabricated under a rotating magnetic field

    Science.gov (United States)

    Yamamoto, Sukeyoshi; Terai, Tomoyuki; Fukuda, Takashi; Sato, Kazunori; Kakeshita, Tomoyuki; Horii, Shigeru; Ito, Mikio; Yonemura, Mitsuharu

    2018-04-01

    We have fabricated a pseudo single crystal of cementite under a rotating magnetic field and investigated its easy and hard axes of magnetization, and determined its magnetocrystalline anisotropy energy. The obtained results are as follows: the hard and easy axes of cementite are the a- and c-axes of the orthorhombic structure with the space group Pnma, respectively. The hard axis observed experimentally was in good agreement with that obtained by an ab initio calculation; however, such consistency was not observed for the easy axis. The magnetocrystalline anisotropy energy was determined as 334 ± 20 kJ/m3 at 5 K.

  19. Magnetoexcitons and Faraday rotation in single-walled carbon nanotubes and graphene nanoribbons

    Science.gov (United States)

    Have, Jonas; Pedersen, Thomas G.

    2018-03-01

    The magneto-optical response of single-walled carbon nanotubes (CNTs) and graphene nanoribbons (GNRs) is studied theoretically, including excitonic effects. Both diagonal and nondiagonal response functions are obtained and employed to compute Faraday rotation spectra. For single-walled CNTs in a parallel field, the results show field-dependent splitting of the exciton absorption peaks caused by brightening a dark exciton state. Similarly, for GNRs in a perpendicular magnetic field, we observe a field-dependent shift of the exciton peaks and the emergence of an absorption peak above the energy gap. Results show that excitonic effects play a significant role in the optical response of both materials, particularly for the off-diagonal tensor elements.

  20. Comparison of functional results of two fixation systems using single-row suturing of rotator cuff.

    Science.gov (United States)

    Muniesa-Herrero, M P; Torres-Campos, A; Urgel-Granados, A; Blanco-Llorca, J A; Floría-Arnal, L J; Roncal-Boj, J C; Castro-Sauras, A

    2018-03-21

    Arthroscopic repair of rotator cuff disorders is a technically demanding but successful procedure. Many anchor and suture alternatives are now available. The choice of the implant by the surgeon is less important than the configuration of the suture used to fix the tendon, however it is necessary to know if there are differences in the results, using each one of them. The aim of the study is to evaluate if there are differences between the knotted and non-knotted implant in terms of functional and satisfaction results. A retrospective study was carried out on 83 patients operated between 2010 and 2014 in our center using 2anchoring systems with and without knotting (39 versus 44 patients respectively), with single row in complete rupture of the rotator cuff. At the end of the follow-up, an average score was obtained on the Constant scale of 74.6 points. 98% of the patients considered the result of the surgery satisfactory. Statistically, there were no significant differences between the 2groups in terms of functionality, satisfaction or reincorporation to activities. The functional results of the single-row cuff suture are satisfactory, although biomechanical studies show advantages in favor of sutures that reproduce a transoseo system. It our series of patients the presence of knotting does not show per se a significant functional difference being both superimposable techniques in absolute values of functionality and patient satisfaction. Copyright © 2018 SECOT. Publicado por Elsevier España, S.L.U. All rights reserved.

  1. Characteristic rotational behaviors of rod-shaped cargo revealed by automated five-dimensional single particle tracking.

    Science.gov (United States)

    Chen, Kuangcai; Gu, Yan; Sun, Wei; Bin Dong; Wang, Gufeng; Fan, Xinxin; Xia, Tian; Fang, Ning

    2017-10-12

    We report an automated single particle tracking technique for tracking the x, y, z coordinates, azimuthal and elevation angles of anisotropic plasmonic gold nanorod probes in live cells. These five spatial coordinates are collectively referred to as 5D. This method overcomes a long-standing challenge in distinguishing rotational motions from translational motions in the z-axis in differential interference contrast microscopy to result in full disclosure of nanoscale motions with high accuracy. Transferrin-coated endocytic gold nanorod cargoes initially undergo active rotational diffusion and display characteristic rotational motions on the membrane. Then as the cargoes being enclosed in clathrin-coated pits, they slow down the active rotation and experience a quiet period before they restore active rotational diffusion after fission and eventually being transported away from the original entry spots. Finally, the 3D trajectories and the accompanying rotational motions of the cargoes are resolved accurately to render the intracellular transport process in live cells.Distinguishing rotational motions from translational motions in the z-axis has been a long-standing challenge. Here the authors develop a five-dimensional single particle tracking method to detect rotational behaviors of nanocargos during clathrin-mediated endocytosis and intracellular transport.

  2. T-junctions and perceived slant of partially occluded surfaces.

    Science.gov (United States)

    Grove, Philip M; Ono, Hiroshi; Kaneko, Hirohiko

    2003-01-01

    Häkkinen and Nyman (1997 Perception 26 29-38) reported that perceived slant is reduced when occlusion is a possible interpretation for the visual system. We present data from three experiments that confirm and expand on their finding. Our stimuli consisted of four types of stereograms depicting white central rectangles flanked on either side by two grey rectangles. The central white rectangles varied in height, thus manipulating the polarity of the T-junction information between the central and flanking rectangles. Perceived slant was smallest or not apparent when T-junction information indicated the central rectangles were nearer than the flanking rectangles and greatest when T-junction information indicated a farther central rectangle. Slant estimates for a stimulus containing a subjective pacmen-induced central rectangle were biased towards a depth step when an occlusion interpretation was possible.

  3. Characterization of single grain by observing magnetic ejection and rotation in microgravity

    Science.gov (United States)

    Uyeda, Chiaki

    A simple and nondestructive method to perform material identification on a single particle is desired in various fields of material science that is concerned with nano-sized particles. We propose a method of identification based on magnetization data, which is obtained from field-induced translation and rotation in microgravity [1]. Material identification is possible from magnetization data because an intrinsic value of susceptibility and anisotropy is assigned to every material according to a data book that compiles the published values [2]. Preliminary ob-servation on free translational motion due to repulsive field-gradient force was reported for mm-sized crystal of corundum [1] and other oxides. Rotational oscillation was observed for various diamagnetic single-crystals in homogeneous field [2]. In order to examine the capability of the above-mentioned material characterization, translation and rotation motion was observed for sub-millimeter-sized quartz, calcite and forsterite in microgravity condition (MGLAB, Japan, duration: 4.5s). It is expected from motional equations that the 2 motions are independent to mass of particles, In a given field distribution, acceleration of translation is expected to be uniquely determined from intrinsic susceptibility of sample. The above properties are exam-ined in the present work by varying experimental parameters. It is noted that observation of the above two motions in microgravity serve as a useful method to detect magnetization of single small particles, be cause the system is free of both sample holder and mass measure-ment. It is expected that magnetization can be measured on a isolated small sample down to nano-level, in condition that motion of the sample is observable. For both susceptibility and anisotropy, range of observed values using microgravity cover the range of compiled published values [2]. Hence material identification is possible for solid material in general. Diamagnetic magnetization and its

  4. Gradient ROtating Outer Volume Excitation (GROOVE): A Novel Method for Single-Shot 2-D OVS

    Science.gov (United States)

    Powell, Nathaniel J.; Jang, Albert; Park, Jang-Yeon; Valette, Julien; Garwood, Michael; Marjańska, Małgorzata

    2014-01-01

    Purpose A new outer volume suppression (OVS) technique is introduced that uses a single pulse and rotating gradients to accomplish frequency-swept excitation. This new technique, which is called Gradient ROtating Outer Volume Excitation (GROOVE), produces a circular or elliptical suppression band rather than suppressing the entire outer volume. Methods Theoretical and k-space descriptions of GROOVE are provided. The properties of GROOVE were investigated with simulations, phantom, and human experiments performed using a 4 T horizontal bore magnet equipped with a TEM coil. Results Similar suppression performance was obtained in phantom and human brain using GROOVE with circular and elliptical shapes. Simulations indicate that GROOVE requires less SAR and time than traditional OVS schemes, but traditional schemes provide a sharper transition zone and less residual signal. Conclusion GROOVE represents a new way of performing OVS in which spins are excited temporally in space on a trajectory which can be tailored to fit the shape of the suppression region. In addition, GROOVE is capable of suppressing tailored regions of space with more flexibility and in a shorter period of time than conventional methods. GROOVE provides a fast, low SAR alternative to conventional OVS methods in some applications (e.g., scalp suppression). PMID:24478130

  5. Femtosecond single electron bunch generation by rotating longitudinal bunch phase space in magnetic field

    International Nuclear Information System (INIS)

    Yang, J.; Kondoh, T.; Kan, K.; Kozawa, T.; Yoshida, Y.; Tagawa, S.

    2006-01-01

    A femtosecond (fs) electron bunching was observed in a photoinjector with a magnetic compressor by rotating the bunch in longitudinal phase space. The bunch length was obtained by measuring Cherenkov radiation of the electron beam with a femtosecond streak camera technique. A single electron bunch with rms bunch length of 98 fs was observed for a 32 MeV electron beam at a charge of 0.17 nC. The relative energy spread and the normalized transverse emittance of the electron beam were 0.2% and 3.8 mm-mrad, respectively. The effect of space charge on the bunch compression was investigated experimentally for charges from 0.17 to 1.25 nC. The dependences of the relative energy spread and the normalized beam transverse emittance on the bunch charge were measured

  6. Strong coupling between a single nitrogen-vacancy spin and the rotational mode of diamonds levitating in an ion trap

    Science.gov (United States)

    Delord, T.; Nicolas, L.; Chassagneux, Y.; Hétet, G.

    2017-12-01

    A scheme for strong coupling between a single atomic spin and the rotational mode of levitating nanoparticles is proposed. The idea is based on spin readout of nitrogen-vacancy centers embedded in aspherical nanodiamonds levitating in an ion trap. We show that the asymmetry of the diamond induces a rotational confinement in the ion trap. Using a weak homogeneous magnetic field and a strong microwave driving we then demonstrate that the spin of the nitrogen-vacancy center can be strongly coupled to the rotational mode of the diamond.

  7. Timing Solution and Single-pulse Properties for Eight Rotating Radio Transients

    Energy Technology Data Exchange (ETDEWEB)

    Cui, B.-Y.; McLaughlin, M. A. [Department of Physics and Astronomy West Virginia University Morgantown, WV 26506 (United States); Boyles, J. [Department of Physics and Astronomy West Kentucky University Bowling Green, KY 42101 (United States); Palliyaguru, N. [Physics and Astronomy Department Texas Tech University Lubbock, TX 79409-1051 (United States)

    2017-05-01

    Rotating radio transients (RRATs), loosely defined as objects that are discovered through only their single pulses, are sporadic pulsars that have a wide range of emission properties. For many of them, we must measure their periods and determine timing solutions relying on the timing of their individual pulses, while some of the less sporadic RRATs can be timed by using folding techniques as we do for other pulsars. Here, based on Parkes and Green Bank Telescope (GBT) observations, we introduce our results on eight RRATs including their timing-derived rotation parameters, positions, and dispersion measures (DMs), along with a comparison of the spin-down properties of RRATs and normal pulsars. Using data for 24 RRATs, we find that their period derivatives are generally larger than those of normal pulsars, independent of any intrinsic correlation with period, indicating that RRATs’ highly sporadic emission may be associated with intrinsically larger magnetic fields. We carry out Lomb–Scargle tests to search for periodicities in RRATs’ pulse detection times with long timescales. Periodicities are detected for all targets, with significant candidates of roughly 3.4 hr for PSR J1623−0841 and 0.7 hr for PSR J1839−0141. We also analyze their single-pulse amplitude distributions, finding that log-normal distributions provide the best fits, as is the case for most pulsars. However, several RRATs exhibit power-law tails, as seen for pulsars emitting giant pulses. This, along with consideration of the selection effects against the detection of weak pulses, imply that RRAT pulses generally represent the tail of a normal intensity distribution.

  8. Timing Solution and Single-pulse Properties for Eight Rotating Radio Transients

    Science.gov (United States)

    Cui, B.-Y.; Boyles, J.; McLaughlin, M. A.; Palliyaguru, N.

    2017-05-01

    Rotating radio transients (RRATs), loosely defined as objects that are discovered through only their single pulses, are sporadic pulsars that have a wide range of emission properties. For many of them, we must measure their periods and determine timing solutions relying on the timing of their individual pulses, while some of the less sporadic RRATs can be timed by using folding techniques as we do for other pulsars. Here, based on Parkes and Green Bank Telescope (GBT) observations, we introduce our results on eight RRATs including their timing-derived rotation parameters, positions, and dispersion measures (DMs), along with a comparison of the spin-down properties of RRATs and normal pulsars. Using data for 24 RRATs, we find that their period derivatives are generally larger than those of normal pulsars, independent of any intrinsic correlation with period, indicating that RRATs’ highly sporadic emission may be associated with intrinsically larger magnetic fields. We carry out Lomb-Scargle tests to search for periodicities in RRATs’ pulse detection times with long timescales. Periodicities are detected for all targets, with significant candidates of roughly 3.4 hr for PSR J1623-0841 and 0.7 hr for PSR J1839-0141. We also analyze their single-pulse amplitude distributions, finding that log-normal distributions provide the best fits, as is the case for most pulsars. However, several RRATs exhibit power-law tails, as seen for pulsars emitting giant pulses. This, along with consideration of the selection effects against the detection of weak pulses, imply that RRAT pulses generally represent the tail of a normal intensity distribution.

  9. Geographical slant facilitates navigation and orientation in virtual environments.

    Science.gov (United States)

    Restat, Jan D; Steck, Sibylle D; Mochnatzki, Horst F; Mallot, Hanspeter A

    2004-01-01

    Theoretical considerations and earlier experimental findings indicate that traveling over slanted terrain can lead to an enrichment of the perceived spatial cues relevant for navigation. We investigated the proposed facilitation of a uniformly slanted environment on navigation and orientation performance with a virtual environment presented on a large 180 degrees screen, using as material a virtual town with eight places and twenty-four landmarks. In the control condition, this town was placed on a flat surface; in the two experimental conditions, the town was placed on a slope with a uniform angle of 4 degrees. Pedaling on a bicycle simulator, participants first explored the environment, then solved navigation tasks, pointed from various positions to distant landmarks, judged the relative elevation of pairs of distant landmarks from memory, and finally drew a sketch map of the environment. In comparison to the control condition, the number of navigation errors was significantly lower in the slanted conditions, and the deviations in the pointings to distant landmarks were massively reduced. Participants from the slant conditions also showed good knowledge of the relative elevations of pairs of distant locations. However, no differences in map-drawing quality were found. The results lend additional support to the proposition that our spatial knowledge, which is used in navigation and orientation, contains vertical information.

  10. Fabrication and characterization of a slanting-type solar water ...

    African Journals Online (AJOL)

    The system includes four major components; a wooden basin of surface area 0.16 m2, an absorber surface, a slanting glass roof and a condensate channel. Very cheap locally available materials were used to fabricate the solar still. The solar still produced an average of 0.09 m3 of distilled water per day, and this study was ...

  11. Slant-Path Rain Attenuation Statistics over Nigeria | Adefolalu ...

    African Journals Online (AJOL)

    Slant path attenuation of microwaves due to rainfall intensities exceeding 0.01 and 0.001per cent of average year have been computed for five different geographical zones in Nigeria, using relevant ITU-R recommendations and global rain rate data. The resulting charts can be used for preliminary estimates of maximum ...

  12. Theory of single-molecule controlled rotation experiments, predictions, tests, and comparison with stalling experiments in F1-ATPase.

    Science.gov (United States)

    Volkán-Kacsó, Sándor; Marcus, Rudolph A

    2016-10-25

    A recently proposed chemomechanical group transfer theory of rotary biomolecular motors is applied to treat single-molecule controlled rotation experiments. In these experiments, single-molecule fluorescence is used to measure the binding and release rate constants of nucleotides by monitoring the occupancy of binding sites. It is shown how missed events of nucleotide binding and release in these experiments can be corrected using theory, with F 1 -ATP synthase as an example. The missed events are significant when the reverse rate is very fast. Using the theory the actual rate constants in the controlled rotation experiments and the corrections are predicted from independent data, including other single-molecule rotation and ensemble biochemical experiments. The effective torsional elastic constant is found to depend on the binding/releasing nucleotide, and it is smaller for ADP than for ATP. There is a good agreement, with no adjustable parameters, between the theoretical and experimental results of controlled rotation experiments and stalling experiments, for the range of angles where the data overlap. This agreement is perhaps all the more surprising because it occurs even though the binding and release of fluorescent nucleotides is monitored at single-site occupancy concentrations, whereas the stalling and free rotation experiments have multiple-site occupancy.

  13. Validity of single term energy expression for ground state rotational band of even-even nuclei

    International Nuclear Information System (INIS)

    Sharma, S.; Kumar, R.; Gupta, J.B.

    2005-01-01

    Full text: There are large numbers of empirical studies of gs band of even-even nuclei in various mass regions. The Bohr-Mottelson's energy expression is E(I) = AX + BX 2 +CX 3 +... where X = I(I+1). The anharmonic vibrator energy expression is: E(I) = al + bl 2 + cl 3 SF model with energy expression: E(I)= pX + qI + rXI... where the terms represents the rotational, vibrational and R-V interaction energy, respectively. The validity f the various energy expressions with two terms had been tested by Sharma for light, medium and heavy mass regions using R I s. R 4 plots (where, spin I=6, 8, 10, 12), which are parameter independent. It was also noted, that of the goodness of energy expression can be judged with the minimum input of energies (i.e. only 2 parameters) and predictability's of the model p to high spins. Recently, Gupta et. al proposed a single term energy expression (SSTE) which was applied for rare earth region. This proposed power law reflected the unity of rotation - vibration in a different way and was successful in explaining the structure of gs-band. It will be useful for test the single term energy expression for light and heavy mass region. The single term expression for energy of ground state band can be written as: E I =axI b , where the index b and the coefficient a are the constant for the band. The values of b+1 and a 1 are as follows: b 1 =log(R 1 )/log(I/2) and a 1 =E I /I b ... The following results were gained: 1) The sharp variation in the value of index b at given spin will be an indication of the change in the shape of the nucleus; 2) The value of E I /I b is fairly constant with spin below back-bending, which reflects the stability of shape with spin; 3) This proposed power law is successful in explaining the structure of gs-band of nuclei

  14. Genome-wide association study for rotator cuff tears identifies two significant single-nucleotide polymorphisms.

    Science.gov (United States)

    Tashjian, Robert Z; Granger, Erin K; Farnham, James M; Cannon-Albright, Lisa A; Teerlink, Craig C

    2016-02-01

    The precise etiology of rotator cuff disease is unknown, but prior evidence suggests a role for genetic factors. Limited data exist identifying specific genes associated with rotator cuff tearing. The purpose of this study was to identify specific genes or genetic variants associated with rotator cuff tearing by a genome-wide association study with an independent set of rotator cuff tear cases. A set of 311 full-thickness rotator cuff tear cases genotyped on the Illumina 5M single-nucleotide polymorphism (SNP) platform were used in a genome-wide association study with 2641 genetically matched white population controls available from the Illumina iControls database. Tests of association were performed with GEMMA software at 257,558 SNPs that compose the intersection of Illumina SNP platforms and that passed general quality control metrics. SNPs were considered significant if P development of rotator cuff tearing. Copyright © 2016 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

  15. Multi-resonance effects within a single chirp in broadband rotational spectroscopy: The rapid adiabatic passage regime for benzonitrile

    Science.gov (United States)

    Schmitz, David; Alvin Shubert, V.; Betz, Thomas; Schnell, Melanie

    2012-10-01

    We report here pronounced, stepwise multi-resonance excitations in benzonitrile arising from a single 1 μs broadband 2-8.3 GHz microwave chirp, observed with our new chirped-pulse broadband rotational spectrometer, COMPACT. Such multi-resonance excitations significantly alter the relative intensity patterns and are a strong indication that, for the given experimental conditions and using benzonitrile as a polar test molecule (μA = 4.5152 D), the rapid adiabatic passage (RAP) regime for strong coupling must be applied. This finding is contrary to previous discussions of chirped-pulse rotational spectroscopy, where the linear fast passage regime of weak coupling has been assumed.

  16. Subunit rotation in a single FoF1-ATP synthase in a living bacterium monitored by FRET

    Science.gov (United States)

    Seyfert, K.; Oosaka, T.; Yaginuma, H.; Ernst, S.; Noji, H.; Iino, R.; Börsch, M.

    2011-03-01

    FoF1-ATP synthase is the ubiquitous membrane-bound enzyme in mitochondria, chloroplasts and bacteria which provides the 'chemical energy currency' adenosine triphosphate (ATP) for cellular processes. In Escherichia coli ATP synthesis is driven by a proton motive force (PMF) comprising a proton concentration difference ΔpH plus an electric potential ΔΨ across the lipid membrane. Single-molecule in vitro experiments have confirmed that proton-driven subunit rotation within FoF1-ATP synthase is associated with ATP synthesis. Based on intramolecular distance measurements by single-molecule fluorescence resonance energy transfer (FRET) the kinetics of subunit rotation and the step sizes of the different rotor parts have been unraveled. However, these experiments were accomplished in the presence of a PMF consisting of a maximum ΔpH ~ 4 and an unknown ΔΨ. In contrast, in living bacteria the maximum ΔpH across the plasma membrane is likely 0.75, and ΔΨ has been measured between -80 and -140 mV. Thus the problem of in vivo catalytic turnover rates, or the in vivo rotational speed in single FoF1-ATP synthases, respectively, has to be solved. In addition, the absolute number of functional enzymes in a single bacterium required to maintain the high ATP levels has to be determined. We report our progress of measuring subunit rotation in single FoF1-ATP synthases in vitro and in vivo, which was enabled by a new labeling approach for single-molecule FRET measurements.

  17. Simplified modelling and analysis of a rotating Euler-Bernoulli beam with a single cracked edge

    Science.gov (United States)

    Yashar, Ahmed; Ferguson, Neil; Ghandchi-Tehrani, Maryam

    2018-04-01

    The natural frequencies and mode shapes of the flapwise and chordwise vibrations of a rotating cracked Euler-Bernoulli beam are investigated using a simplified method. This approach is based on obtaining the lateral deflection of the cracked rotating beam by subtracting the potential energy of a rotating massless spring, which represents the crack, from the total potential energy of the intact rotating beam. With this new method, it is assumed that the admissible function which satisfies the geometric boundary conditions of an intact beam is valid even in the presence of a crack. Furthermore, the centrifugal stiffness due to rotation is considered as an additional stiffness, which is obtained from the rotational speed and the geometry of the beam. Finally, the Rayleigh-Ritz method is utilised to solve the eigenvalue problem. The validity of the results is confirmed at different rotational speeds, crack depth and location by comparison with solid and beam finite element model simulations. Furthermore, the mode shapes are compared with those obtained from finite element models using a Modal Assurance Criterion (MAC).

  18. Single photon emission computerized tomography

    International Nuclear Information System (INIS)

    Hooge, P. de.

    1983-01-01

    In this thesis two single-photon emission tomographic techniques are presented: (a) longitudinal tomography with a rotating slanting-hole collimator, and (b) transversal tomography with a rotating gamma camera. These methods overcome the disadvantages of conventional scintigraphy. Both detection systems and the image construction methods are explained and comparisons with conventional scintigraphy are drawn. One chapter is dedicated to the determination of system parameters like spatial resolution, contrast, detector uniformity, and size of the object, by phantom studies. In separate chapters the results are presented of detection of tumors and metastases in the liver and the liver hilus; skeletal diseases; various pathological aberrations of the brain; and myocardial perfusion. The possible use of these two ect's for other organs and body areas is discussed in the last chapter. (Auth.)

  19. Direct Vertebral Rotation Versus Single Concave Rod Rotation: Low-dose Intraoperative Computed Tomography Evaluation of Spine Derotation in Adolescent Idiopathic Scoliosis Surgery.

    Science.gov (United States)

    Pankowski, Rafal; Roclawski, Marek; Ceynowa, Marcin; Mikulicz, Marcin; Mazurek, Tomasz; Kloc, Wojciech

    2016-05-01

    A comparative clinical study of two main corrective manoeuvres in scoliosis surgery. To compare the effectiveness of two main corrective manoeuvres: single concave rod rotation (SCRR) and direct vertebral rotation (DVR) in regard to apical vertebral rotation (AVR) and rib hump correction in adolescent idiopathic scoliosis (AIS) surgery. It remains unclear whether SCRR manoeuvre alone causes apical vertebral derotation (AVD) and rib hump correction. Although the influence of DVR on AVD and rib hump change has been described, it has been evaluated mainly with indirect methods. This is the first study to evaluate separately the derotational effectiveness of these two manoeuvres during the low-dose intraoperative computed tomography (ICT). A study group consisted of 38 AIS patients treated by posterior scoliosis surgery (PSS) with all pedicle screw constructs. All examined patients had dow-dose ICT evaluation (before correction, after SCRR, and after DVR). We found SCRR ineffective - mean postcorrectional AVR increased insignificantly 1.5° (16.1% worsening) P = 0.170. On the contrary, an average postcorrectional AVR after DVR decreased significantly mean 3.1° (33.3% improvement) P = 0.049. Precorrectional rib hump angle was 19.3°, after SCRR 15°, and after DVR 12.3°. It was found that despite the lack of true derotation after SCRR there was a significant 22.3% decrease of the rib hump P = 0.043. Although the rib hump decreased significantly 36.3% after DVR as well P = 0.023. There was also significant difference between a rib hump angle after SCRR and DVR (P = 0.049). SCRR does not lead to AVD. The true spinal derotation is possible only when DVR systems are used. The decrease of rib hump is achieved after both SCRR and DVR, but the improvement is significantly better after DVR. 3.

  20. Design and investigations of a microstrip fed open V-shape slot antenna for wideband dual slant polarization

    Directory of Open Access Journals (Sweden)

    R.V.S. Ram Krishna

    2015-12-01

    Full Text Available A dual slant polarized slot antenna is proposed. The antenna is printed on the two sides of a single substrate and has two microstrip feed lines to excite a V-shaped slot formed by the merging of two tilted rectangular step shaped slots. Stepping of the slot sections as well as the feed line improves the impedance matching. A narrow rectangular metallic stub is introduced at the junction of the slot arms to improve the decoupling between the ports. The antenna polarization is +450/−450 with respect to horizontal under alternate excitation and this dual slant polarized nature is demonstrated through aperture electric field plots and far field radiation patterns. The measured return loss bandwidth (S11 < −10 dB of the antenna is from 2.3 GHz and extends beyond 12 GHz while the measured isolation bandwidth (S21 < −20 dB is from 5 GHz onwards. The time domain characterization of the antenna is also done by calculating the fidelity factor. For evaluating the diversity performance, the envelope correlation coefficients are calculated from the simulated and measured S-parameters. The correlation coefficients are well below the acceptable values. With a peak gain varying between 3 and 5 dBi, the antenna is expected to be useful for wideband dual slant polarized applications.

  1. Advanced Propfan Engine Technology (APET) definition study, single and counter-rotation gearbox/pitch change mechanism design

    Science.gov (United States)

    Anderson, R. D.

    1985-01-01

    Single-rotation propfan-powered regional transport aircraft were studied to identify key technology development issues and programs. The need for improved thrust specific fuel consumption to reduce fuel burned and aircraft direct operating cost is the dominant factor. Typical cycle trends for minimizing fuel consumption are reviewed, and two 10,000 shp class engine configurations for propfan propulsion systems for the 1990's are presented. Recommended engine configurations are both three-spool design with dual spool compressors and free power turbines. The benefits of these new propulsion system concepts were evaluated using an advanced airframe, and results are compared for single-rotation propfan and turbofan advanced technology propulsion systems. The single-rotation gearbox is compared to a similar design with current technology to establish the benefits of the advanced gearbox technology. The conceptual design of the advanced pitch change mechanism identified a high pressure hydraulic system that is superior to the other contenders and completely external to the gearboxes.

  2. Effects of slant angle and illumination angle on MTF estimations

    CSIR Research Space (South Africa)

    Vhengani, LM

    2012-07-01

    Full Text Available angle d(?) was not constant. It was also noted that the iris of the imaging system was in most cases adjusted during initial setups of each measurements. After each measurement, the knife-edge target was replaced with the ISO 12233 MTF target (shown....085 0.09 0.095 K:\\Working Folder\\Project_On_orbit MTF\\edgetargets\\MTF_Lab_Measurements _20120302_Edge Slant Angle (degrees) Ny qu ist MT F (c yc le/p ixe l) Data Regression -18 -16 -14 -12 -10 -8 -6 -4 -2 0.05 0.055 0.06 0...

  3. Retroflection from slanted coastlines-circumventing the "vorticity paradox"

    Directory of Open Access Journals (Sweden)

    V. Zharkov

    2008-12-01

    Full Text Available The balance of long-shore momentum flux requires that the solution of zonally retroflecting currents involve ring shedding on the western side. An important aspect of the ring dynamics is the ring intensity α (analogous to the Rossby number, which reaches its maximum value of unity when the upstream potential vorticity (PV is zero. Friction leads to a slow-down and a decrease in α. The main difficulty is that the solution of the system of equations for conservation of mass and momentum of zonal currents leads to the conclusion that the ratio (Φ of the mass flux going into the rings and the total incoming mass flux is approximately 4α/(1+2α. This yields the "vorticity paradox" – only relatively weak rings (α≤1/2 could satisfy the necessary condition Φ≤1. Physically, this means, for example, that the momentum-flux of zero PV currents upstream is so high that, no matter how many rings are produced and, no matter what size they are, they cannot compensate for it.

    To avoid this paradox, we develop a nonlinear analytical model of retroflection from a slanted non-zonal coastline. We show that when the slant of coastline (γ exceeds merely 150, Φ does not reach unity regardless of the value of α. Namely, the paradox disappears even for small slants. Our slowly varying nonlinear solution does not only let us circumvent the paradox. It also gives a detailed description of the rings growth rate and the mass flux going into the rings as a function of time. For example, in the case of zero PV and zero thickness of the upper layer along the coastline, the maximal values of Φ can be approximately expressed as, 1.012+0.32exp(−γ/3.41−γ/225. Interestingly, for significant slants γ≥300, the rings reach a terminal size corresponding to a balance between the β-force and both the upstream and downstream momentum fluxes. This terminal size is unrelated to the ultimate

  4. The coherent interlayer resistance of a single, rotated interface between two stacks of AB graphite

    Energy Technology Data Exchange (ETDEWEB)

    Habib, K. M. Masum, E-mail: khabib@ee.ucr.edu; Sylvia, Somaia S.; Neupane, Mahesh; Lake, Roger K., E-mail: rlake@ee.ucr.edu [Department of Electrical Engineering, University of California, Riverside, California 92521-0204 (United States); Ge, Supeng [Department of Physics and Astronomy, University of California, Riverside, California 92521-0204 (United States)

    2013-12-09

    The coherent, interlayer resistance of a misoriented, rotated interface between two stacks of AB graphite is determined for a variety of misorientation angles. The quantum-resistance of the ideal AB stack is on the order of 1 to 10 mΩ μm{sup 2}. For small rotation angles, the coherent interlayer resistance exponentially approaches the ideal quantum resistance at energies away from the charge neutrality point. Over a range of intermediate angles, the resistance increases exponentially with cell size for minimum size unit cells. Larger cell sizes, of similar angles, may not follow this trend. The energy dependence of the interlayer transmission is described.

  5. The coherent interlayer resistance of a single, rotated interface between two stacks of AB graphite

    International Nuclear Information System (INIS)

    Habib, K. M. Masum; Sylvia, Somaia S.; Neupane, Mahesh; Lake, Roger K.; Ge, Supeng

    2013-01-01

    The coherent, interlayer resistance of a misoriented, rotated interface between two stacks of AB graphite is determined for a variety of misorientation angles. The quantum-resistance of the ideal AB stack is on the order of 1 to 10 mΩ μm 2 . For small rotation angles, the coherent interlayer resistance exponentially approaches the ideal quantum resistance at energies away from the charge neutrality point. Over a range of intermediate angles, the resistance increases exponentially with cell size for minimum size unit cells. Larger cell sizes, of similar angles, may not follow this trend. The energy dependence of the interlayer transmission is described

  6. Development and applications of single particle orientation and rotational tracking in dynamic systems

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Kuangcai [Iowa State Univ., Ames, IA (United States)

    2016-02-19

    The goal of this study is to help with future data analysis and experiment designs in rotational dynamics research using DIC-based SPORT technique. Most of the current studies using DIC-based SPORT techniques are technical demonstrations. Understanding the mechanisms behind the observed rotational behaviors of the imaging probes should be the focus of the future SPORT studies. More efforts are still needed in the development of new imaging probes, particle tracking methods, instrumentations, and advanced data analysis methods to further extend the potential of DIC-based SPORT technique.

  7. Design and Fabrication of a Slanted-Beam MEMS Accelerometer

    Directory of Open Access Journals (Sweden)

    Wei Xu

    2017-03-01

    Full Text Available This paper presents a novel capacitive microelectromechanical systems (MEMS accelerometer with slanted supporting beams and all-silicon sandwich structure. Its sensing mechanism is quite similar to an ordinary sandwich-type MEMS accelerometer, except that its proof mass is suspended by a beam parallel to the {111} plane of a (100 silicon wafer. In this way, each sensing element can detect accelerations in two orthogonal directions. Four of these sensing elements could work together and constitute a 3-axis micro-accelerometer by using a simple planar assembly process. This design avoids the traditional 3-axis accelerometer’ disadvantage of possible placement inaccuracy when assembling on three different planes and largely reduces the package volume. The slanted-beam accelerometer’s performance was modeled and analyzed by using both analytical calculations and finite element method (FEM simulations. A prototype of one sensing element was fabricated and tested. Measured results show that this accelerometer has a good bias stability 76.8 ppm (1σ, tested immediately after power on, two directional sensitivities (sensitivity angle α = 45.4° and low nonlinearity (<0.5% over a sensing range up to ±50 g, which demonstrates a great opportunity for future high-precision three-axis inertial measurement.

  8. The Need of Slanted Side Holes for Venous Cannulae

    Directory of Open Access Journals (Sweden)

    Joong Yull Park

    2012-01-01

    Full Text Available Well-designed cannulae must allow good flow rate and minimize nonphysiologic load. Venous cannulae generally have side holes to prevent the rupture of blood vessel during perfusion. Optimizing side hole angle will yield more efficient and safe venous cannulae. A numerical modeling was used to study the effect of the angle (0°–45° and number (0–12 of side holes on the performance of cannulae. By only slanting the side holes, it increases the flow rate up to 6% (in our models. In addition, it was found that increasing the number of side holes reduces the shear rate up to 12% (in our models. A new parameter called “penetration depth” was introduced to describe the interfering effect of stream jets from side holes, and the result showed that the 45°-slanted side holes caused minimum interfering for the flow in cannula. Our quantitative hemodynamic analysis study provides important guidelines for venous cannulae design.

  9. Creation of single-photon entangled states around rotating black holes

    Science.gov (United States)

    Racorean, Ovidiu

    2018-02-01

    Recently, numerical simulations showed that X-ray photons emitted by accretion disks acquire rotation of polarization angle and orbital angular momentum due to strong gravitational field in the vicinity of the rotating black holes. Based on these two degrees of freedom we construct a bipartite two-level quantum system of the accretion disks photons. To characterize the quantum states of this composite system we consider linear entropy for the reduced density matrix of polarization with the intention to exploit its direct relation with the photons degree of polarization. Accordingly, the minimum degree of polarization of X-ray radiation located in the transition region of the accretion disk indicates a high value of the linear entropy for the photons emitted on this region, inferring a high degree of entanglement in the composite system. We emphasize that for an extreme rotating black hole in the thermal state, the photons with energies at the thermal peak are maximally entangled in polarization and orbital angular momentum, leading to the creation of all four Bell states. Detection and measurement of quantum information encoded in photons emitted in the accretion disk around rotating black holes may be performed by actual quantum information technology.

  10. The transverse colon cancer with the reversed rotation of the midgut treated with single incision laparoscopic colectomy.

    Science.gov (United States)

    Hirano, Yasumitsu; Hattori, Masakazu; Fujita, Manami; Nishida, Youji; Douden, Kenji; Hashizume, Yasuo

    2013-06-01

    Reversed rotation of the midgut is a rare type of intestinal malrotation. Moreover, synchronous colon cancer has rarely been reported. Preliminary experience with single-incision laparoscopic colectomy (SILC) for colon cancer with reversed rotation of the midgut is reported. An 82-year-old woman was admitted because of a fecal occult blood. A colonoscopy revealed transverse colon cancer. An air-barium contrast enema showed the right-sided sigmoid colon and the left-sided cecum. A computed tomography revealed that the duodenum and the transverse colon were situated at the ventral side of the superior mesenteric artery, and a preoperative diagnosis of suspicion of reversed rotation of the midgut was made. First, a lap protector was inserted through a 4.0 cm transumbilical incision. Four 5 mm ports were placed in the lap protector. On the observation of laparoscopy, the cecum and the ascending colon were not fixed with the retroperitoneum and situated on the left, and the sigmoid colon was situated on the right. We successfully mobilized the transverse colon using a single-incision laparoscopic approach. Resection was achieved following extracorporealization, and the anastomosis was performed extracorporeally using staplers. The patient was discharged on the thirteenth postoperative day. Postoperative follow-up did not reveal any umbilical wound complications. SILC for colon cancer associated with malrotation of the midgut is feasible and a promising alternative method because of its less invasiveness and its adaptability to the malrotation without extending the skin incision.

  11. Observing pure effects of counter-rotating terms without ultrastrong coupling: A single photon can simultaneously excite two qubits

    Science.gov (United States)

    Wang, Xin; Miranowicz, Adam; Li, Hong-Rong; Nori, Franco

    2017-12-01

    The coherent process that a single photon simultaneously excites two qubits has recently been theoretically predicted by Garziano et al. [L. Garziano, V. Macrì, R. Stassi, O. Di Stefano, F. Nori, and S. Savasta, One Photon Can Simultaneously Excite two or More Atoms, Phys. Rev. Lett. 117, 043601 (2016), 10.1103/PhysRevLett.117.043601]. We propose a different approach to observe a similar dynamical process based on a superconducting quantum circuit, where two coupled flux qubits longitudinally interact with the same resonator. We show that this simultaneous excitation of two qubits (assuming that the sum of their transition frequencies is close to the cavity frequency) is related to the counter-rotating terms in the dipole-dipole coupling between two qubits, and the standard rotating-wave approximation is not valid here. By numerically simulating the adiabatic Landau-Zener transition and Rabi-oscillation effects, we clearly verify that the energy of a single photon can excite two qubits via higher-order transitions induced by the longitudinal couplings and the counter-rotating terms. Compared with previous studies, the coherent dynamics in our system only involves one intermediate state and, thus, exhibits a much faster rate. We also find transition paths which can interfere. Finally, by discussing how to control the two longitudinal-coupling strengths, we find a method to observe both constructive and destructive interference phenomena in our system.

  12. Effects of foot rotation positions on knee valgus during single-leg drop landing: Implications for ACL injury risk reduction.

    Science.gov (United States)

    Teng, P S P; Kong, P W; Leong, K F

    2017-06-01

    Non-contact anterior cruciate ligament (ACL) injuries commonly occur when athletes land in high risk positions such as knee valgus. The position of the foot at landing may influence the transmission of forces from the ankle to the knee. Using an experimental approach to manipulate foot rotation positions, this study aimed to provide new insights on how knee valgus during single-leg landing may be influenced by foot positions. Eleven male recreational basketball players performed single-leg drop landings from a 30-cm high platform in three foot rotation positions (toe-in, toe-forward and toe-out) at initial contact. A motion capture system and a force plate were used to measure lower extremity kinematics and kinetics. Knee valgus angles at initial contact (KVA) and maximum knee valgus moments (KVM), which were known risk factors associated with ACL injury, were measured. A one-way repeated measures Analysis of Variance was conducted (α=0.05) to compare among the three foot positions. Foot rotation positions were found to have a significant effect on KVA (p<0.001, η 2 =0.66) but the difference between conditions (about 1°) was small and not clinically meaningful. There was a significant effect of foot position on KVM (p<0.001, η 2 =0.55), with increased moment observed in the toe-out position as compared to toe-forward (p=0.012) or toe-in positions (p=0.002). When landing with one leg, athletes should avoid extreme toe-out foot rotation positions to minimise undesirable knee valgus loading associated with non-contact ACL injury risks. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Large-Scale Single Particle and Cell Trapping based on Rotating Electric Field Induced-Charge Electroosmosis.

    Science.gov (United States)

    Wu, Yupan; Ren, Yukun; Tao, Ye; Hou, Likai; Jiang, Hongyuan

    2016-12-06

    We propose a simple, inexpensive microfluidic chip for large-scale trapping of single particles and cells based on induced-charge electroosmosis in a rotating electric field (ROT-ICEO). A central floating electrode array, was placed in the center of the gap between four driving electrodes with a quadrature configuration and used to immobilize single particles or cells. Cells were trapped on the electrode array by the interaction between ROT-ICEO flow and buoyancy flow. We experimentally optimized the efficiency of trapping single particles by investigating important parameters like particle or cell density and electric potential. Experimental and numerical results showed good agreement. The operation of the chip was verified by trapping single polystyrene (PS) microspheres with diameters of 5 and 20 μm and single yeast cells. The highest single particle occupancy of 73% was obtained using a floating electrode array with a diameter of 20 μm with an amplitude voltage of 5 V and frequency of 10 kHz for PS microbeads with a 5-μm diameter and density of 800 particles/μL. The ROT-ICEO flow could hold cells against fluid flows with a rate of less than 0.45 μL/min. This novel, simple, robust method to trap single cells has enormous potential in genetic and metabolic engineering.

  14. IMPROVEMENT IN HANDWRITTEN NUMERAL STRING RECOGNITION BY SLANT NORMALIZATION AND CONTEXTUAL INFORMATION

    NARCIS (Netherlands)

    Britto jr., A. de S.; Sabourin, R.; Lethelier, E.; Bortolozzi, F.; Suen, C.Y.

    2004-01-01

    This work describes a way of enhancing handwritten numeral string recognition by considering slant normalization and contextual information to train an implicit segmentation­based system. A word slant normalization method is modified in order to improve the results for handwritten numeral strings.

  15. Observation of slant column NO2 using the super-zoom mode of AURA-OMI

    NARCIS (Netherlands)

    Valin, L.C.; Russell, A.R.; Bucsela, E.J.; Veefkind, J.P.; Cohen, R.C.

    2011-01-01

    We retrieve slant column NO2 from the superzoom mode of the Ozone Monitoring Instrument (OMI) to explore its utility for understanding NOx emissions and variability. Slant column NO2 is operationally retrieved from OMI (Boersma et al., 2007; Bucsela et al., 2006) with a nadir footprint of 13×24 km2,

  16. Dynamic analysis of a geared rotor system considering a slant crack on the shaft

    Science.gov (United States)

    Han, Qinkai; Zhao, Jingshan; Chu, Fulei

    2012-12-01

    The vibration problems associated with geared systems have been the focus of research in recent years. As the torque is mainly transmitted by the geared system, a slant crack is more likely to appear on the gear shaft. Due to the slant crack and its breathing mechanism, the dynamic behavior of cracked geared system would differ distinctly with that of uncracked system. Relatively less work is reported on slant crack in the geared rotor system during the past research. Thus, the dynamic analysis of a geared rotor-bearing system with a breathing slant crack is performed in the paper. The finite element model of a geared rotor with slant crack is presented. Based on fracture mechanics, the flexibility matrix for the slant crack is derived that accounts for the additional stress intensity factors. Three methods for whirling analysis, parametric instability analysis and steady-state response analysis are introduced. Then, by taking a widely used one-stage geared rotor-bearing system as an example, the whirling frequencies of the equivalent time-invariant system, two types of instability regions and steady-state response under the excitations of unbalance forces and tooth transmission errors, are computed numerically. The effects of crack depth, position and type (transverse or slant) on the system dynamic behaviors are considered in the discussion. The comparative study with slant cracked geared rotor is carried out to explore distinctive features in their modal, parametric instability and frequency response behaviors.

  17. Effect of the compressive stress on both polarization rotation and phase transitions in PMN-30%PT single crystal

    Directory of Open Access Journals (Sweden)

    Hui Zhang

    2014-05-01

    Full Text Available In this paper, we have investigated the dependence of both the electromechanical effect and the electrostriction on the compressive stress in PMN-30%PT single crystal on the basis of single domain polarization rotation model. In the model, the electroelastic energy induced by the compressive stress is taken into account. The results have demonstrated that the compressive stress can lead to a significant change in the initial polarization state in the crystal. The reason lies in the stress induced anisotropy which is the coupling between the compressive stress and the electrostrictive coefficients. Thus, the initial polarization state in single crystal is determined by the combination of both electrocrystalline anisotropy and the stress induced anisotropy. The compressive stress along the [100] axis can make the polarization in the crystal be perpendicular to the stress direction, and make it difficult to be polarized to the saturation. This model is useful for better understanding both the polarization rotation and electromechanical effect in ferroelectric crystals with the compressive stress present.

  18. Applications of slant collimators to cardiovascular nuclear medicine

    International Nuclear Information System (INIS)

    Nishimura, Tsunehiko; Uehara, Toshio; Hayashi, Makoto; Kagawa, Masaaki; Kozuka, Takahiro

    1980-01-01

    The RI examination of hearts is attracting increasingly interest as cardiovascular nuclear medicine in recent years. As for the background, there are the development of such radioactive agents with high heart-muscle specificity as 201 TICI and the minicomputer capability of measuring rapid contraction and expansion of hearts. Under the situation, the variety of contrivance in collimators is attempted for higher accuracy in grasping the form and function of hearts. With a 30 deg inclination slant type collimator (made by EDC firm) which became available, its applications as cardiovascular nuclear medicine have been examined in heart-muscle scintigraphy and heart RI angiography. These results are described. In the above connection, a bifocal collimator and a seven pinhole collimator are also explained briefly. (J.P.N.)

  19. Visual slant misperception and the Black-Hole landing situation

    Science.gov (United States)

    Perrone, J. A.

    1983-01-01

    A theory which explains the tendency for dangerously low approaches during night landing situations is presented. The two dimensional information at the pilot's eye contains sufficient information for the visual system to extract the angle of slant of the runway relative to the approach path. The analysis is depends upon perspective information which is available at a certain distance out from the aimpoint, to either side of the runway edgelights. Under black hole landing conditions, however, this information is not available, and it is proposed that the visual system use instead the only available information, the perspective gradient of the runway edgelights. An equation is developed which predicts the perceived approach angle when this incorrect parameter is used. The predictions are in close agreement with existing experimental data.

  20. Visual slant misperception and the 'black-hole' landing situation

    Science.gov (United States)

    Perrone, J. A.

    1984-01-01

    A theory which explains the tendency for dangerously low approaches during night landing situations is presented. The two-dimensional information at the pilot's eye contains sufficient information for the visual system to extract the angle of slant of the runway relative to the approach path. The analysis depends upon perspective information which is available at a certain distance out from the aimpoint, to either side of the runway edgelights. Under black hole landing conditions, however, this information is not available, and it is proposed that the visual system use instead the only available information, the perspective gradient of the runway edgelights. An equation is developed which predicts the perceived approach angle when this incorrect parameter is used. The predictions are in close agreement with existing experimental data.

  1. Magnetization distribution of single-particle states and 2/sup +/ rotational states from muonic atoms

    CERN Document Server

    Backe, H; Engfer, R; Kankeleit, E; Link, R; Michaelsen, R; Petitjean, C; Schellenberg, L; Schneuwly, H; Schröder, W U; Vuilleumier, J L; Walter, H K; Zehnder, A

    1973-01-01

    The lowest states in muonic atoms are rather sensitive to the spatial distribution of the nuclear magnetization density, and several results were deduced from the broadening of the muonic 2p/sub 1/2/-1s/sub 1/2/ and 3d/sub 3/2/-2p/sub 1/2/ transitions. By measuring low energetic transitions such as the 2s/sub 1/2/-2p/sub 1/2/ transition or nuclear gamma -transitions, it is possible to resolve the magnetic hyperfine splittings. The magnetic hf splitting of the 2s/sub 1/2/-2p/sub 1/2/ transition in mu /sup 115/In and of the 3/2/sup +/-1/2/sup +/ nuclear gamma -transitions in mu /sup 203/Tl at 279 keV, and in mu /sup 205/Tl at 204 keV, have been resolved. For the 2/sup +/-0/sup +/ nuclear gamma -transition in mu /sup 190,192/Os at 187 keV and 206 keV, respectively, the magnetic hf splitting of the 2/sup +/ rotational levels and the intensities of the hf components were determined from a nearly resolved doublet splitting. (7 refs).

  2. Results of single-staged rotational osteotomy in a child with congenital proximal radioulnar synostosis: subjective and objective evaluation.

    Science.gov (United States)

    Shingade, Viraj U; Shingade, Rashmi V; Ughade, Suresh N

    2014-01-01

    For congenital proximal radioulnar synostosis, both conservative and operative treatments have been described. Most of the studies describing surgical interventions are based on subjective evaluation of the forearm function and have used severe degree of forearm pronation as an indication for surgery. This study describes a single-staged rotational osteotomy of the proximal third ulna and distal third radius. The aim of the study was to assess the utility of the described surgical procedure by subjective and objective evaluations of the forearm function. Forty-eight children with congenital proximal radioulnar synostosis were evaluated by subjective and objective assessments and were followed up prospectively. Subjective evaluation consisted of a set of 12 questions regarding the basic activities of life. Objective evaluation was made using the Jebsen-Taylor hand-function test and a classification system used by Failla and colleagues for 15 tasks described by Morrey and colleagues. Eleven children were treated conservatively. Thirty-six children underwent a single-staged rotational osteotomy of the proximal third ulna and distal third radius. After surgery, the evaluations were repeated. The mean age at surgery was 8.6±3.7 years, and the mean postoperative follow-up period was 54±13 months. All operated forearms showed a statistically significant improvement in functioning after surgery as per the subjective and objective evaluations. The mean time taken to carry out all activities before surgery was 47.7+10.0 seconds, which significantly reduced to 33.3+6.6 seconds after surgery (P=0.0001) as per the results of the Jebsen-Taylor hand-function test. All good (n=19) and fair (n=11) results were converted to excellent (n=30) after surgery as per the modified Failla classification. There were no neurovascular injuries as compared with other published techniques. Only 1 child had delayed union, and 1 had persistent dorsal angulation at the radial osteotomy site. For

  3. Gradient rotating outer volume excitation (GROOVE): A novel method for single-shot two-dimensional outer volume suppression.

    Science.gov (United States)

    Powell, Nathaniel J; Jang, Albert; Park, Jang-Yeon; Valette, Julien; Garwood, Michael; Marjańska, Małgorzata

    2015-01-01

    To introduce a new outer volume suppression (OVS) technique that uses a single pulse and rotating gradients to accomplish frequency-swept excitation. This new technique, which is called gradient rotating outer volume excitation (GROOVE), produces a circular or elliptical suppression band rather than suppressing the entire outer volume. Theoretical and k-space descriptions of GROOVE are provided. The properties of GROOVE were investigated with simulations, phantom, and human experiments performed using a 4T horizontal bore magnet equipped with a TEM coil. Similar suppression performance was obtained in phantom and human brain using GROOVE with circular and elliptical shapes. Simulations indicate that GROOVE requires less SAR and time than traditional OVS schemes, but traditional schemes provide a sharper transition zone and less residual signal. GROOVE represents a new way of performing OVS in which spins are excited temporally in space on a trajectory that can be tailored to fit the shape of the suppression region. In addition, GROOVE is capable of suppressing tailored regions of space with more flexibility and in a shorter period of time than conventional methods. GROOVE provides a fast, low SAR alternative to conventional OVS methods in some applications (e.g., scalp suppression). © 2014 Wiley Periodicals, Inc.

  4. Continuous blood fractionation using an array of slanted grooves

    Science.gov (United States)

    Bernate, Jorge A.; Chengxun, Liu; Lagae, Liesbet; Drazer, German

    2011-11-01

    Blood is a complex fluid having different specialized biological functions and containing a plethora of clinical information. The separation of different blood components is a crucial step in many research and clinical applications. In this work we take advantage of the flow characteristics in microfluidic devices in which the bottom surface is patterned with slanted rectangular grooves to continuously fractionate blood. We exploit the flow in the vicinity of the patterned surface when the dimensions of the grooves are much smaller than the dimensions of the main channel. In these devices, we observed that the grooves act as open channels guiding flow along them with the flow over them being in the direction of the main channel. We present experiments in which the different blood components are deflected laterally to a different extent by the flow along the grooves depending on their sedimentation velocity, which allows their continuous fractionation. In particular, the heavier red blood cells experience the largest deflection while the lighter white blood cells deflect the least, allowing their passive and minimally invasive isolation. In addition, this fluidic platform can also be used to separate magnetically labeled circulating cancer cells which can be retained in the flow along the grooves using a sufficiently strong magnetic force.

  5. Slant hole completion test (1991) sidetrack ``as built`` report

    Energy Technology Data Exchange (ETDEWEB)

    Myal, F.R.

    1992-05-01

    During the summer of 1990, a slant hole test well, funded by the US Department of Energy, was drilled to 9,466 ft to evaluate the effectiveness of directional drilling in the tight, naturally fractured gas sands and coals of the Mesaverde Group. The surface location of the SHCT No. 1 is 700 ft south of the DOE Multiwell Experiment (MWX) site in Section 34, T6S, R94W, Garfield County, Colorado, approximately 7.5 miles west of Rifle. Mechanical problems following cementing of a production liner resulted in loss of the completion interval, and operations were suspended. In early 1991, DOE decided to sidetrack the hole to permit production testing of the lost interval. The sidetrack was designed to parallel the original wellbore, but to be drilled 1,000 ft to the east to minimize the chances of encountering formation damage from the original hole. The sidetrack, like the original hole, was to intersect the paludal lenticular sands and coals at 60{degrees} and to penetrate the underlying Cozzette sand horizonally. The sidetrack was spudded May 12, 1991. After re-entering the well in late 1991, early production testing of the Cozzette showed that the 300 ft of in-pay horizontal hole can produce at rate 5 to 10 times higher than vertical wells in the same area. This report contains the geological summary and sidetrack drilling operations summary.

  6. Single-row vs. double-row arthroscopic rotator cuff repair: clinical and 3 Tesla MR arthrography results.

    Science.gov (United States)

    Tudisco, Cosimo; Bisicchia, Salvatore; Savarese, Eugenio; Fiori, Roberto; Bartolucci, Dario A; Masala, Salvatore; Simonetti, Giovanni

    2013-01-27

    Arthroscopic rotator cuff repair has become popular in the last few years because it avoids large skin incisions and deltoid detachment and dysfunction. Earlier arthroscopic single-row (SR) repair methods achieved only partial restoration of the original footprint of the tendons of the rotator cuff, while double-row (DR) repair methods presented many biomechanical advantages and higher rates of tendon-to-bone healing. However, DR repair failed to demonstrate better clinical results than SR repair in clinical trials. MR imaging at 3 Tesla, especially with intra-articular contrast medium (MRA), showed a better diagnostic performance than 1.5 Tesla in the musculoskeletal setting. The objective of this study was to retrospectively evaluate the clinical and 3 Tesla MRA results in two groups of patients operated on for a medium-sized full-thickness rotator cuff tear with two different techniques. The first group consisted of 20 patients operated on with the SR technique; the second group consisted of 20 patients operated on with the DR technique. All patients were evaluated at a minimum of 3 years after surgery. The primary end point was the re-tear rate at 3 Tesla MRA. The secondary end points were the Constant-Murley Scale (CMS), the Simple Shoulder Test (SST) scores, surgical time and implant expense. The mean follow-up was 40 months in the SR group and 38.9 months in the DR group. The mean postoperative CMS was 70 in the SR group and 68 in the DR group. The mean SST score was 9.4 in the SR group and 10.1 in the DR group. The re-tear rate was 60% in the SR group and 25% in the DR group. Leakage of the contrast medium was observed in all patients. To the best of our knowledge, this is the first report on 3 Tesla MRA in the evaluation of two different techniques of rotator cuff repair. DR repair resulted in a statistically significant lower re-tear rate, with longer surgical time and higher implant expense, despite no difference in clinical outcomes. We think that

  7. Single-row vs. double-row arthroscopic rotator cuff repair: clinical and 3 Tesla MR arthrography results

    Directory of Open Access Journals (Sweden)

    Tudisco Cosimo

    2013-01-01

    Full Text Available Abstract Background Arthroscopic rotator cuff repair has become popular in the last few years because it avoids large skin incisions and deltoid detachment and dysfunction. Earlier arthroscopic single-row (SR repair methods achieved only partial restoration of the original footprint of the tendons of the rotator cuff, while double-row (DR repair methods presented many biomechanical advantages and higher rates of tendon-to-bone healing. However, DR repair failed to demonstrate better clinical results than SR repair in clinical trials. MR imaging at 3 Tesla, especially with intra-articular contrast medium (MRA, showed a better diagnostic performance than 1.5 Tesla in the musculoskeletal setting. The objective of this study was to retrospectively evaluate the clinical and 3 Tesla MRA results in two groups of patients operated on for a medium-sized full-thickness rotator cuff tear with two different techniques. Methods The first group consisted of 20 patients operated on with the SR technique; the second group consisted of 20 patients operated on with the DR technique. All patients were evaluated at a minimum of 3 years after surgery. The primary end point was the re-tear rate at 3 Tesla MRA. The secondary end points were the Constant-Murley Scale (CMS, the Simple Shoulder Test (SST scores, surgical time and implant expense. Results The mean follow-up was 40 months in the SR group and 38.9 months in the DR group. The mean postoperative CMS was 70 in the SR group and 68 in the DR group. The mean SST score was 9.4 in the SR group and 10.1 in the DR group. The re-tear rate was 60% in the SR group and 25% in the DR group. Leakage of the contrast medium was observed in all patients. Conclusions To the best of our knowledge, this is the first report on 3 Tesla MRA in the evaluation of two different techniques of rotator cuff repair. DR repair resulted in a statistically significant lower re-tear rate, with longer surgical time and higher implant

  8. Single-molecule detection of chaperonin dynamics through polarization rotation modulation of CdSe QD luminescence imaging

    International Nuclear Information System (INIS)

    Tani, Toshiro; Oda, Masaru; Araki, Daisuke; Miyashita, Tatsuki; Nakajima, Koudai; Arita, Mayuno; Yohda, Masafumi

    2014-01-01

    We report our recent trials examining the single-molecule three-dimensional (3D) detection of protein conformational dynamics at room temperature. Using molecular chaperones as model proteins and cadmium selenide (CdSe) semiconductor quantum dots (QDs) as nanometer-scale probes, we monitored the temporal evolution of ATP-induced conformation changes with a total internal reflection fluorescence (TIRF) microscopy imaging technique in buffer solutions. The two-dimensional (2D) degenerate nature of the emission dipoles of the QDs, due to the uniaxial wurtzite crystal structure, made it possible to capture the 3D orientation using a polarization modulation technique in real time. The temporal resolution was half the period of analyzer rotation. Although still insufficient, the obtained signals suggest possible 3D detection of specific motions, which supports the two-step conformational changes triggered by ATP attachment. - Highlights: • We report our recent trials examining the single-molecule three-dimensional (3D) detection of protein conformational dynamics at room temperature. • Using molecular chaperones as model proteins and cadmium selenide (CdSe) semiconductor quantum dots (QDs) as nanometer-scale probes, we monitored the temporal evolution of ATP-induced conformation changes with a total internal reflection fluorescence (TIRF) microscopy imaging technique in buffer solutions. • The two-dimensional (2D) degenerate nature of the emission dipoles of the QDs, due to the uniaxial wurtzite crystal structure, made it possible to capture the 3D orientation using a polarization modulation technique in real time. • The temporal resolution was half the period of analyzer rotation. • Although still insufficient, the obtained signals suggest possible 3D detection of specific motions, which supports the two-step conformational changes triggered by ATP attachment

  9. Gold dimer nanoantenna with slanted gap for tunable LSPR and improved SERS

    KAUST Repository

    Kessentini, Sameh

    2014-02-13

    We focus on improving the surface-enhanced Raman scattering (SERS) of dimer nanoantenna by tailoring the shape of the coupled nanoantennas extremities from rounded to straight or slanted ones. A numerical model based on the discrete dipole approximation method-taking into account periodicity, adhesion layer, and roughness-is first validated by comparison with localized surface plasmon resonance (LSPR) and SERS experiments on round-edged dimer nanoantennas and then used to investigate the effect of the straight or slanted gap in the dimer antenna. Simulations show that both LSPR and SERS can be tuned by changing the gap slanting angle. The SERS enhancement factor can also be improved by 2 orders of magnitude compared to the one reached using a rounded gap. Therefore, the slanting angle can be used as a new control parameter in the design of SERS substrates to guarantee stronger field confinement and higher sensitivity, especially as its feasibility is demonstrated. © 2014 American Chemical Society.

  10. Single leg jumping neuromuscular control is improved following whole body, long-axis rotational training.

    Science.gov (United States)

    Nyland, John; Burden, Robert; Krupp, Ryan; Caborn, David N M

    2011-04-01

    Improved lower extremity neuromuscular control during sports may decrease injury risk. This prospective study evaluated progressive resistance, whole body, long-axis rotational training on the Ground Force 360 device. Our hypothesis was that device training would improve lower extremity neuromuscular control based on previous reports of kinematic, ground reaction force (GRF) or electromyographic (EMG) evidence of safer or more efficient dynamic knee stability during jumping. Thirty-six healthy subjects were randomly assigned to either training (Group 1) or control (Group 2) groups. Using a pre-test, post-test study design data were collected from three SLVJ trials. Unpaired t-tests with adjustments for multiple comparisons were used to evaluate group mean change differences (P≤0.05/25≤0.002). During propulsion Group 1 standardized EMG amplitude mean change differences for gluteus maximus (-21.8% vs. +17.4%), gluteus medius (-28.6% vs. +15.0%), rectus femoris (-27.1% vs. +11.2%), vastus medialis (-20.2% vs. +9.1%), and medial hamstrings (-38.3% vs. +30.3%) differed from Group 2. During landing Group 1 standardized EMG amplitude mean change differences for gluteus maximus (-32.9% vs. +11.1%) and rectus femoris (-33.3% vs. +29.0%) also differed from Group 2. Group 1 peak propulsion vertical GRF (+0.24N/kg vs. -0.46N/kg) and landing GRF stabilization timing (-0.68 vs. +0.05s) mean change differences differed from Group 2. Group 1 mean hip (-16.3 vs. +7.8°/s) and knee (-21.4 vs. +18.5°/s) flexion velocity mean change differences also differed from Group 2. Improved lower extremity neuromuscular efficiency, increased peak propulsive vertical GRF, decreased mean hip and knee flexion velocities during landing, and earlier landing stabilization timing in the training group suggests improved lower extremity neuromuscular control. Copyright © 2010 Elsevier Ltd. All rights reserved.

  11. Stress Intensity Factors of Slanted Cracks in Bi-Material Plates

    Science.gov (United States)

    Ismail, Al Emran; Azhar Kamarudin, Kamarul; Nor, Nik Hisyamudin Muhd

    2017-10-01

    In this study, the stress intensity factors (SIF) of slanted cracks in bi-material plates subjected to mode I loading is numerically solved. Based on the literature survey, tremendous amount of research works are available studying the normal cracks in both similar and dissimilar plates. However, lack of SIF behavior for slanted cracks especially when it is embedded in bi-material plates. The slanted cracks are then modelled numerically using ANSYS finite element program. Two plates of different in mechanical properties are firmly bonded obliquely and then slanted edge cracks are introduced at the lower inclined edge. Isoparametric singular element is used to model the crack tip and the SIF is determined which is based on the domain integral method. Three mechanical mismatched and four slanted angles are used to model the cracks. According to the present results, the effects of mechanical mismatch on the SIF for normal cracks are not significant. However, it is played an important role when slanted angles are introduced. It is suggested that higher SIF can be obtained when the cracks are inclined comparing with the normal cracks. Consequently, accelerating the crack growth at the interface between two distinct materials.

  12. Stability and dynamics of rotor system with 45° slant crack on shaft

    Science.gov (United States)

    Lin, Yanli; Si, Xiaohui; Chu, Fulei

    2011-06-01

    Crack on a shaft is one of the common damages in a rotor system. In this paper, transverse vibrations are calculated to compare the influences of transverse crack and slant crack on the rotor system. Results show that the vibration amplitude of the rotor system with a 45° slant crack on the shaft is larger than that with a transverse crack when the two types of crack have the same depth and the rotor system runs in the same condition. Stability and dynamic characteristics of the rotor system with a 45° slant crack on the shaft under torsional excitation are analyzed by considering opening and closing of the crack. It is shown that the instability of the transverse vibration of the rotor system increases with increasing difference between the bending stiffness in two main directions, and the vibration is stable when the two bending stiffness are identical. The spectrum analysis of the steadystate response reveals that the gravity and the eccentricity produce different frequency components, and when the two bending stiffness are identical, the multiple frequency components of the torsional excitation disappear. Further investigation shows that the vibration amplitudes in combined frequencies increase rapidly in transversal, torsional, and axial vibration with increasing slant crack depth. The results are helpful for the understanding the dynamic behavior of a rotor system with a slant crack on a shaft and can be used for the detection of the slant crack on a shaft.

  13. Eccentric versus conventional exercise therapy in patients with rotator cuff tendinopathy: a randomized, single blinded, clinical trial

    NARCIS (Netherlands)

    Dejaco, B.; Habets, B.; Loon, C.J.M. van; Grinsven, S. van; Cingel, R.E. van

    2017-01-01

    PURPOSE: To investigate the effectiveness of isolated eccentric versus conventional exercise therapy in patients with rotator cuff tendinopathy. METHODS: Thirty-six patients with rotator cuff tendinopathy, diagnosed by an orthopaedic surgeon, were included and randomly allocated to an isolated

  14. Characterization of Vadose Zone Sediment: Slant Borehole SX-108 in the S-SX Waste Management Area

    Energy Technology Data Exchange (ETDEWEB)

    Serne, R. Jeffrey; Last, George V.; Schaef, Herbert T.; Lanigan, David C.; Lindenmeier, Clark W.; Ainsworth, Calvin C.; Clayton, Ray E.; Legore, Virginia L.; O' Hara, Matthew J.; Brown, Christopher F.; Orr, Robert D.; Kutnyakov, Igor V.; Wilson, Teresa C.; Wagnon, Kenneth B.; Williams, Bruce A.; Burke, Deborah S.

    2008-09-11

    This report was revised in September 2008 to remove acid-extractable sodium data from Table 4.17. The sodium data was removed due to potential contamination introduced during the acid extraction process. The rest of the text remains unchanged from the original report issued in February 2002. The overall goal of the of the Tank Farm Vadose Zone Project, led by CH2M HILL Hanford Group, Inc., is to define risks from past and future single-shell tank farm activities. To meet this goal, CH2M HILL Hanford Group, Inc., asked scientists from Pacific Northwest National Laboratory to perform detailed analyses on vadose zone sediment from within the S-SX Waste Management Area. This report is the fourth in a series of four reports to present the results of these analyses. Specifically, this report contains all the geologic, geochemical, and selected physical characterization data collected on vadose zone sediment recovered from a slant borehole installed beneath tank SX-108 (or simply SX-108 slant borehole).

  15. Gamma emission tomosynthesis based on an automated slant hole collimation system

    Science.gov (United States)

    Pellegrini, R.; Pani, R.; Cinti, M. N.; Longo, M.; Lo Meo, S.; Viviano, M.

    2015-03-01

    The imaging capabilities of radioisotope molecular imaging systems are limited by their ring geometry and by the object-to-detector distance, which impairs spatial resolution, efficiency and image quality. These detection capabilities could be enhanced by performing acquisitions with dedicated gamma cameras placed in close proximity to the object that has to be examined. The main aim of this work is to develop a compact camera suitable for detecting small and low-contrast lesions, with a higher detection efficiency than conventional SPECT, through a gamma emission tomosynthesis method. In this contribution a prototype of a new automated slant hole collimator, coupled to a small Field of View (FoV) gamma camera, is presented. The proposed device is able to acquire planar projection images at different angles without rotating around the patient body; these projection images are then three-dimensional reconstructed. Therefore, in order to perform the volumetric reconstruction of the studied object, the traditional Back Projection (BP) reconstruction is compared with the Shift And Add (SAA) method. In order to verify the effectiveness of the technique and to test the image reconstruction algorithms, a Monte Carlo simulation, based on the GEANT4 code, was implemented. The method was also validated by a set of experimental measurements. The discussed device is designed to work in patient proximity for detecting lesions placed at a distances ranged from 0 to 8 cm, thus allowing few millimeters planar resolutions and sagittal resolution of about 2 cm. The new collimation method implies high-resolution capabilities demonstrated by reconstructing the projection images through the BP and the SAA methods. The latter is simpler than BP and produces comparable spatial resolutions with respect to the traditional tomographic method, while preserving the image counts.

  16. Computer-assisted and patient-specific 3-D planning and evaluation of a single-cut rotational osteotomy for complex long-bone deformities

    NARCIS (Netherlands)

    Dobbe, J. G. G.; Pré, K. J. du; Kloen, P.; Blankevoort, L.; Streekstra, G. J.

    2011-01-01

    Malunion after long bone fracture results in an incorrect position of the distal bone segment. This misalignment may lead to reduced function of the limb, early osteoarthritis and chronic pain. An established treatment option is a corrective osteotomy. For complex malunions, a single-cut rotational

  17. Inter-technique validation of tropospheric slant total delays

    Directory of Open Access Journals (Sweden)

    M. Kačmařík

    2017-06-01

    Full Text Available An extensive validation of line-of-sight tropospheric slant total delays (STD from Global Navigation Satellite Systems (GNSS, ray tracing in numerical weather prediction model (NWM fields and microwave water vapour radiometer (WVR is presented. Ten GNSS reference stations, including collocated sites, and almost 2 months of data from 2013, including severe weather events were used for comparison. Seven institutions delivered their STDs based on GNSS observations processed using 5 software programs and 11 strategies enabling to compare rather different solutions and to assess the impact of several aspects of the processing strategy. STDs from NWM ray tracing came from three institutions using three different NWMs and ray-tracing software. Inter-techniques evaluations demonstrated a good mutual agreement of various GNSS STD solutions compared to NWM and WVR STDs. The mean bias among GNSS solutions not considering post-fit residuals in STDs was −0.6 mm for STDs scaled in the zenith direction and the mean standard deviation was 3.7 mm. Standard deviations of comparisons between GNSS and NWM ray-tracing solutions were typically 10 mm ± 2 mm (scaled in the zenith direction, depending on the NWM model and the GNSS station. Comparing GNSS versus WVR STDs reached standard deviations of 12 mm ± 2 mm also scaled in the zenith direction. Impacts of raw GNSS post-fit residuals and cleaned residuals on optimal reconstructing of GNSS STDs were evaluated at inter-technique comparison and for GNSS at collocated sites. The use of raw post-fit residuals is not generally recommended as they might contain strong systematic effects, as demonstrated in the case of station LDB0. Simplified STDs reconstructed only from estimated GNSS tropospheric parameters, i.e. without applying post-fit residuals, performed the best in all the comparisons; however, it obviously missed part of tropospheric signals due to non-linear temporal and spatial variations

  18. ON SPACELIKE BIHARMONIC SLANT HELICES ACCORDING TO BISHOP FRAME IN THE LORENTZIAN GROUP OF RIGID MOTIONS E(1,1

    Directory of Open Access Journals (Sweden)

    Talat Körpınar

    2012-01-01

    Full Text Available In this paper, we study spacelike biharmonic slant helices according to Bishop frame in the Lorentzian group of rigid motions E(1,1. We characterize the spacelike biharmonic slant helices in terms of their curvatures in the Lorentzian group of rigid motions E(1,1. Finally, we obtain parametric equations of spacelike biharmonic slant helices according to Bishop frame in the Lorentzian group of rigid motions E(1,1.

  19. Single-frequency pulsed Brillouin-thulium fiber laser at 2 µm with nonlinear polarization rotation and active phase modulation

    Science.gov (United States)

    Wang, Xiong; Lv, Haibin; Zhou, Pu; Wu, Weijun; Wang, Xiaolin; Xiao, Hu; Liu, Zejin

    2014-10-01

    We present a single-frequency (SF) pulsed fiber laser at 2 µm based on stimulated Brillouin scattering in a thulium-doped fiber laser. The effective feedback of the fiber laser is quite weak to induce pulse operation. Nonlinear polarization rotation and active phase modulation are employed to compress the pulse width and stabilize the pulse train. This SF pulsed Brillouin-thulium fiber laser (BTFL) can generate a stable pulse train with a repetition rate of ˜310 kHz and a pulse width of ˜200 ns. The repetition rate of the pulse train can be adjusted by controlling the cavity length, and the pulse width can be tuned between 200 and 500 ns. The central wavelength locates at 1971.58 nm with an optical signal-to-noise ratio of more than 40 dB, and the linewidth is about 6 MHz. This is the first demonstration of the SF pulsed BTFL as far as we know.

  20. Whole body, long-axis rotational training improves lower extremity neuromuscular control during single leg lateral drop landing and stabilization.

    Science.gov (United States)

    Nyland, John; Burden, Robert; Krupp, Ryan; Caborn, David N M

    2011-05-01

    Poor neuromuscular control during sports activities is associated with non-contact lower extremity injuries. This study evaluated the efficacy of progressive resistance, whole body, long-axis rotational training to improve lower extremity neuromuscular control during a single leg lateral drop landing and stabilization. Thirty-six healthy subjects were randomly assigned to either Training or Control groups. Electromyographic, ground reaction force, and kinematic data were collected from three pre-test, post-test trials. Independent sample t-tests with Bonferroni corrections for multiple comparisons were used to compare group mean change differences (P≤0.05/21≤0.0023). Training group gluteus maximus and gluteus medius neuromuscular efficiency improved 35.7% and 31.7%, respectively. Training group composite vertical-anteroposterior-mediolateral ground reaction force stabilization timing occurred 1.35s earlier. Training group knee flexion angle at landing increased by 3.5°. Training group time period between the initial two peak frontal plane knee displacements following landing increased by 0.17s. Training group peak hip and knee flexion velocity were 21.2°/s and 20.1°/s slower, respectively. Time period between the initial two peak frontal plane knee displacements following landing and peak hip flexion velocity mean change differences displayed a strong relationship in the Training group (r(2)=0.77, P=0.0001) suggesting improved dynamic frontal plane knee control as peak hip flexion velocity decreased. This study identified electromyographic, kinematic, and ground reaction force evidence that device training improved lower extremity neuromuscular control during single leg lateral drop landing and stabilization. Further studies with other populations are indicated. Copyright © 2010 Elsevier Ltd. All rights reserved.

  1. PIV and Rotational Raman-Based Temperature Measurements for CFD Validation in a Single Injector Cooling Flow

    Science.gov (United States)

    Wernet, Mark P.; Georgiadis, Nicholas J.; Locke, Randy J.

    2018-01-01

    Film cooling is used in a wide variety of engineering applications for protection of surfaces from hot or combusting gases. The design of more efficient thin film cooling geometries/configurations could be facilitated by an ability to accurately model and predict the effectiveness of current designs using computational fluid dynamics (CFD) code predictions. Hence, a benchmark set of flow field property data were obtained for use in assessing current CFD capabilities and for development of better turbulence models. Both Particle Image Velocimetry (PIV) and spontaneous rotational Raman scattering (SRS) spectroscopy were used to acquire high quality, spatially-resolved measurements of the mean velocity, turbulence intensity and also the mean temperature and normalized root mean square (rms) temperatures in a single injector cooling flow arrangement. In addition to flowfield measurements, thermocouple measurements on the plate surface enabled estimates of the film effectiveness. Raman spectra in air were obtained across a matrix of radial and axial locations downstream from a 68.07 mm square nozzle blowing heated air over a range of temperatures and Mach numbers, across a 30.48cm long plate equipped with a single injector cooling hole. In addition, both centerline streamwise 2-component PIV and cross-stream 3-component Stereo PIV data at 15 axial stations were collected in the same flows. The velocity and temperature data were then compared against Wind-US CFD code predictions for the same flow conditions. The results of this and planned follow-on studies will support NASA's development and assessment of turbulence models for heated flows.

  2. Experimental Q-dependence of the rotational J = 0-to-1 transition of molecular hydrogen adsorbed in single-wall carbon nanotube bundles

    International Nuclear Information System (INIS)

    Georgiev, P.A.; Giannasi, A.; Ross, D.K.; Zoppi, M.; Sauvajol, J.L.; Stride, J.

    2006-01-01

    Inelastic neutron scattering spectra of para-Hydrogen adsorbed in single-wall carbon nanotubes have been measured at 20 K, at different surface loadings, and at a set of kinematic trajectories. These show the presence of at least two different adsorption sites in the nanotube bundle. Only a weak hindrance to rotation is observed on the more adsorptive site which is preferentially occupied at low H 2 concentrations while a completely free rotation was found at the second and weaker site where the determined centre-of-mass dynamics suggests H 2 -H 2 distances similar to those on the graphite surface and in the bulk solid

  3. Free hand proprioception is well calibrated to verbal estimates of slanted surfaces.

    Science.gov (United States)

    Shaffer, Dennis M; Taylor, Ally

    2017-02-01

    We investigate the relationship between verbal and hand proprioception of slant. In Experiment 1 we demonstrate that verbally estimating free hand orientation produces overestimates by a factor of 1.67. These values are similar to those seen for verbal overestimates of slanted surfaces. In Experiment 2, participants positioned their hand to a ramp at 1 of 4 different orientations, and then verbally estimated the orientation of either their hand or the ramp. We show that verbal estimates of the ramp are a product of the orientation of their hand and the perception of the orientation of their hand. We discuss how this work is consistent with the proprioception calibration hypothesis that proposes that similar biases exist in both verbal estimates of visually perceived slant and proprioceptively perceived hand orientation and how this may explain free hand estimates to outdoor hills that are greater than actual hill orientation by a factor of ~2, but are still less than verbal (over)estimates.

  4. Moiré-reduction method for slanted-lenticular-based quasi-three-dimensional displays

    Science.gov (United States)

    Zhuang, Zhenfeng; Surman, Phil; Zhang, Lei; Rawat, Rahul; Wang, Shizheng; Zheng, Yuanjin; Sun, Xiao Wei

    2016-12-01

    In this paper we present a method for determining the preferred slanted angle for a lenticular film that minimizes moiré patterns in quasi-three-dimensional (Q3D) displays. We evaluate the preferred slanted angles of the lenticular film for the stripe-type sub-pixel structure liquid crystal display (LCD) panel. Additionally, the sub-pixels mapping algorithm of the specific angle is proposed to assign the images to either the right or left eye channel. A Q3D display prototype is built. Compared with the conventional SLF, this newly implemented Q3D display can not only eliminate moiré patterns but also provide 3D images in both portrait and landscape orientations. It is demonstrated that the developed slanted lenticular film (SLF) provides satisfactory 3D images by employing a compact structure, minimum moiré patterns and stabilized 3D contrast.

  5. Simulation of V/G During Φ450 mm Czochralski Grown Silicon Single Crystal Growth Under the Different Crystal and Crucible Rotation Rates

    Directory of Open Access Journals (Sweden)

    Guan X J

    2016-01-01

    Full Text Available For discovering the principle of processing parameter combination for the stable growth and better wafer quality of Φ450 mm Czochralski grown silicon single crystal (shortly called Cz silicon crystal, the effects of crystal rotation rate and crucible one on the V/G ratio were simulated by using CGSim software. The results show that their effect laws on the V/G ratio for Φ450 mm Cz silicon crystal growth are some different from that for Φ200 mm Cz silicon one, and the effects of crucible rotation rate are relatively smaller than that of crystal one and its increasing only makes the demarcation point between two regions with different V/G ratio variations outward move along radial direction, and it promotes the wafer quality to weaken crystal rotation rate and strengthen crucible one.

  6. Fixation method does not affect restoration of rotation center in hip replacements: A single-site retrospective study

    OpenAIRE

    Wegner, Alexander; Kauther, Max Daniel; Landgraeber, Stefan; von Knoch, Marius

    2012-01-01

    Abstract Background Aseptic loosening is one of the greatest problems in hip replacement surgery. The rotation center of the hip is believed to influence the longevity of fixation. The aim of this study was to compare the influence of cemented and cementless cup fixation techniques on the position of the center of rotation because cemented cup fixation requires the removal of more bone for solid fixation than the cementless technique. Methods We retrospectively compared pre- and post-operativ...

  7. Plastic Limit Loads for Slanted Circumferential Through-Wall Cracked Pipes Using 3D Finite-Element Limit Analyses

    International Nuclear Information System (INIS)

    Jang, Hyun Min; Cho, Doo Ho; Kim, Young Jin; Huh, Nam Su; Shim, Do Jun; Choi, Young Hwan; Park, Jung Soon

    2011-01-01

    On the basis of detailed 3D finite-element (FE) limit analyses, the plastic limit load solutions for pipes with slanted circumferential through-wall cracks (TWCs) subjected to axial tension, global bending, and internal pressure are reported. The FE model and analysis procedure employed in the present numerical study were validated by comparing the present FE results with existing solutions for plastic limit loads of pipes with idealized TWCs. For the quantification of the effect of slanted crack on plastic limit load, slant correction factors for calculating the plastic limit loads of pipes with slanted TWCs from pipes with idealized TWCs are newly proposed from extensive 3D FE calculations. These slant-correction factors are presented in tabulated form for practical ranges of geometry and for each set of loading conditions

  8. Fixation method does not affect restoration of rotation center in hip replacements: A single-site retrospective study

    Directory of Open Access Journals (Sweden)

    Wegner Alexander

    2012-06-01

    Full Text Available Abstract Background Aseptic loosening is one of the greatest problems in hip replacement surgery. The rotation center of the hip is believed to influence the longevity of fixation. The aim of this study was to compare the influence of cemented and cementless cup fixation techniques on the position of the center of rotation because cemented cup fixation requires the removal of more bone for solid fixation than the cementless technique. Methods We retrospectively compared pre- and post-operative positions of the hip rotation center in 25 and 68 patients who underwent artificial hip replacements in our department in 2007 using cemented or cementless cup fixation, respectively, with digital radiographic image analysis. Results The mean horizontal and vertical distances between the rotation center and the acetabular teardrop were compared in radiographic images taken pre- and post-operatively. The mean horizontal difference was −2.63 mm (range: -11.00 mm to 10.46 mm, standard deviation 4.23 mm for patients who underwent cementless fixation, and −2.84 mm (range: -10.87 to 5.30 mm, standard deviation 4.59 mm for patients who underwent cemented fixation. The mean vertical difference was 0.60 mm (range: -20.15 mm to 10.00 mm, standard deviation 3.93 mm and 0.41 mm (range: -9.26 mm to 6.54 mm, standard deviation 3.58 mm for the cementless and cemented fixation groups, respectively. The two fixation techniques had no significant difference on the position of the hip rotation center in the 93 patients in this study. Conclusions The hip rotation center was similarly restored using either the cemented or cementless fixation techniques in this patient cohort, indicating that the fixation technique itself does not interfere with the position of the center of rotation. To completely answer this question further studies with more patients are needed.

  9. Design and determination of the efficiency of a slanting-type solar ...

    African Journals Online (AJOL)

    The solar water distillation system is a non-toxic and promising device for water purification. A slanting-type solar water distillation kit was fabricated and tested outdoor under the meteorological conditions of Imo State University, Owerri, Nigeria. The system consists of four major components; a wooden basin of surface area ...

  10. Observation of slant column NO2 using the super-zoom mode of AURA-OMI

    Directory of Open Access Journals (Sweden)

    R. C. Cohen

    2011-09-01

    Full Text Available We retrieve slant column NO2 from the super-zoom mode of the Ozone Monitoring Instrument (OMI to explore its utility for understanding NOx emissions and variability. Slant column NO2 is operationally retrieved from OMI (Boersma et al., 2007; Bucsela et al., 2006 with a nadir footprint of 13 × 24 km2, the result of averaging eight detector elements on board the instrument. For 85 orbits in late 2004, OMI reported observations from individual "super-zoom" detector elements (spaced at 13 × 3 km2 at nadir. We assess the spatial response of these individual detector elements in-flight and determine an upper-bound on spatial resolution of 9 km, in good agreement with on-ground calibration (7 km FWHM. We determine the precision of the super-zoom mode to be 2.1 × 1015 molecules cm−2, approximately a factor of √8 lower than an identical retrieval at operational scale as expected if random noise dominates the uncertainty. We retrieve slant column NO2 over the Satpura power plant in India; Seoul, South Korea; Dubai, United Arab Emirates; and a set of large point sources on the Rihand Reservoir in India using differential optical absorption spectroscopy (DOAS. Over these sources, the super-zoom mode of OMI observes variation in slant column NO2 of up to 30 × the instrumental precision within one operational footprint.

  11. Steady-state, elastic-plastic growth of slanted cracks in symmetrically loaded plates

    DEFF Research Database (Denmark)

    Nielsen, Kim Lau; Hutchinson, J. W.

    2017-01-01

    of the plate, the problem would be mode I, but due to the slant the local conditions along the crack front are a combination of mode I and mode III. A three-dimensional formulation for steady-state crack propagation is employed to generate distributions of effective stress, stress triaxiality and Lode...

  12. Radiative-transfer models for explosions from rotating and non-rotating single WC stars. Implications for SN 1998bw and LGRB/SNe

    Science.gov (United States)

    Dessart, Luc; John Hillier, D.; Yoon, Sung-Chul; Waldman, Roni; Livne, Eli

    2017-07-01

    Using 1D, non-local thermodynamic equilibrium and time-dependent radiative transfer simulations, we study the ejecta properties required to match the early- and late-time photometric and spectroscopic properties of supernovae (SNe) associated with long-duration γ-ray bursts (LGRBs). Matching the short rise time, narrow light curve peak and extremely broad spectral lines of SN 1998bw requires a model with ≲3 M⊙ ejecta but a high explosion energy of a few 1052 erg and 0.5 M⊙ of 56Ni. The relatively high luminosity, presence of narrow spectral lines of intermediate mass elements, and low ionisation at the nebular stage, however, are matched with a more standard C-rich Wolf-Rayet (WR) star explosion, an ejecta of ≳10 M⊙, an explosion energy ≳1051 erg, and only 0.1 M⊙ of 56Ni. As the two models are mutually exclusive, the breaking of spherical symmetry is essential to match the early- and late-time photometric and spectroscopic properties of SN 1998bw. This conclusion confirms the notion that the ejecta of SN 1998bw is highly aspherical on large scales. More generally, with asphericity, the energetics and 56Ni masses of LGRB/SNe are reduced and their ejecta masses are increased, favouring a massive fast-rotating Wolf-Rayet star progenitor. Contrary to persisting claims in favour of the proto-magnetar model for LGRB/SNe, such progenitor/ejecta properties are compatible with collapsar formation. Ejecta properties of LGRB/SNe inferred from 1D radiative-transfer modelling are fundamentally flawed.

  13. Studies on the concentration dependence of specific rotation of Alpha lactose monohydrate (α-LM) aqueous solutions and growth of α-LM single crystals

    Science.gov (United States)

    Vinodhini, K.; Divya Bharathi, R.; Srinivasan, K.

    2018-02-01

    Lactose is an optically active substance. As it is one of the reducing sugars, exhibits mutarotation in solution when it dissolves in any solvent. In solution, lactose exists in two isomeric forms, alpha-Lactose (α-L) and beta-lactose (β-L) through the mutarotation reaction. Mutarotation produces a dynamic equilibrium between two isomers in a solution and kinetics of this process determines the growth rate of alpha lactose monohydrate (α-LM) crystals. Since no data were available on the specific rotation of aqueous α-LM solutions at different concentrations at 33 °C, the initial experiments were carried out on the specific rotation of aqueous α-LM solutions at different concentrations at 33 °C. The specific rotations of the solutions were decreased with increasing time through the mutarotation reaction. The initial and final (equilibrium) specific rotations of the solutions were determined by using automatic digital polarimeter. The compositions of α and β-L in all prepared solutions were calculated from initial and final optical rotations by the method of Sharp and Doob. The composition of α-L decreased whereas, the composition of β-L increased in solutions with increasing concentration of α-LM at 33 °C. Experimental results revealed that this method could be easily and safely employed to study the dependence of specific rotation of solutions on their concentration. The effect of β-lactose on the morphology of nucleated α-LM single crystals has been studied at different experimental conditions.

  14. Eccentric versus conventional exercise therapy in patients with rotator cuff tendinopathy: a randomized, single blinded, clinical trial.

    Science.gov (United States)

    Dejaco, Beate; Habets, Bas; van Loon, Corné; van Grinsven, Susan; van Cingel, Robert

    2017-07-01

    To investigate the effectiveness of isolated eccentric versus conventional exercise therapy in patients with rotator cuff tendinopathy. Thirty-six patients with rotator cuff tendinopathy, diagnosed by an orthopaedic surgeon, were included and randomly allocated to an isolated eccentric exercise (EE) group (n = 20, mean age = 50.2 ± 10.8 years) or a conventional exercise (CG) group (n = 16, mean age = 48.6 ± 12.3 years). Both groups fulfilled a 12-week daily home-based exercise programme and received a total amount of nine treatment sessions. The Constant Murley score was used to evaluate both objective (e.g. range of motion and strength) and subjective measures (e.g. pain and activities of daily living). A visual analogue scale (VAS) was used to evaluate pain during daily activities. As secondary outcomes, shoulder range of motion and isometric abduction strength in 45° in the scapular plane were evaluated. All measurements were taken at baseline, at 6, 12 and 26 weeks. After 26 weeks, both groups showed a significant increase in the Constant Murley score and a significant decrease in VAS scores. No difference was found between the groups, for any of the evaluated outcome measures. A 12-week-isolated eccentric training programme of the rotator cuff is beneficial for shoulder function and pain after 26 weeks in patients with rotator cuff tendinopathy. However, it is no more beneficial than a conventional exercise programme for the rotator cuff and scapular muscles. Based on the results, clinicians should take into account that performing two eccentric exercises twice a day is as effective as performing six concentric/eccentric exercises once a day in patients with rotator cuff tendinopathy.

  15. Single- vs. double-bundle anterior cruciate ligament reconstruction: a new aspect of knee assessment during activities involving dynamic knee rotation.

    Science.gov (United States)

    Czamara, Andrzej; Królikowska, Aleksandra; Szuba, Łukasz; Widuchowski, Wojciech; Kentel, Maciej

    2015-02-01

    Few studies have compared single-bundle (SB) and double-bundle (DB) anterior cruciate ligament reconstruction (ACLR) in the knee joint during activities involving change-of-direction maneuvers and knee rotation. This study examined whether the type of ACLR contributes to postphysiotherapy outcomes, with an emphasis on knee function assessment during activities involving dynamic knee rotation. Fifteen male patients after SB ACLR and 15 male patients after DB ACLR took part in the same physiotherapy program. Twenty-four weeks after ACLR, both groups underwent anterior laxity measurement, pivot shift tests, range of movement and joint circumference measurements, subjective assessment of pain and stability levels in the knee joint, peak torque measurement of the muscles rotating the tibia toward the femur, and a run test with maximal speed and change-of-direction maneuvers. Comparative analysis did not show any differences between the results of anterior tibial translation, pivot shift test, range of movement and joint circumference, and subjective assessment of pain and knee joint stability levels. No differences were noted between the groups in peak torque values obtained from the muscles responsible for internal and external tibial rotation or results of the run test. The data obtained from this study can be used by research teams to monitor and compare the effectiveness of various study protocols involving surgical and physiotherapy treatment. The data are especially useful when combined with the clinical assessment of patients who would like to return to sport.

  16. Effects of local microwave diathermy on shoulder pain and function in patients with rotator cuff tendinopathy in comparison to subacromial corticosteroid injections: a single-blind randomized trial.

    Science.gov (United States)

    Rabini, Alessia; Piazzini, Diana B; Bertolini, Carlo; Deriu, Laura; Saccomanno, Maristella F; Santagada, Domenico A; Sgadari, Antonio; Bernabei, Roberto; Fabbriciani, Carlo; Marzetti, Emanuele; Milano, Giuseppe

    2012-04-01

    Single-blind randomized clinical trial, with a follow-up of 24 weeks. To determine the effects of hyperthermia via localized microwave diathermy on pain and disability in comparison to subacromial corticosteroid injections in patients with rotator cuff tendinopathy. Hyperthermia improves symptoms and function in several painful musculoskeletal disorders. However, the effects of microwave diathermy in rotator cuff tendinopathy have not yet been established. Ninety-two patients with rotator cuff tendinopathy and pain lasting for at least 3 months were recruited from the outpatient clinic of the Department of Orthopaedics and Traumatology, University Hospital, Rome, Italy. Participants were randomly allocated to either local microwave diathermy or subacromial corticosteroids. The primary outcome measure was the short form of the Disabilities of the Arm, Shoulder and Hand Questionnaire (QuickDASH). Secondary outcome measures were the Constant-Murley shoulder outcome score and a visual analog scale for pain assessment. At the end of treatment and at follow-up, both treatment groups experienced improvements in all outcome measures relative to baseline values. Changes over time in QuickDASH, Constant-Murley, and visual analog scale scores were not different between treatment arms. In patients with rotator cuff tendinopathy, the effects of localized microwave diathermy on disability, shoulder function, and pain are equivalent to those elicited by subacromial corticosteroid injections.

  17. Natural ventilation in insect screened single span greenhouses ...

    African Journals Online (AJOL)

    screened side vents were assessed in single greenhouses in terms of the difference in temperature and humidity inside and outside under tropical conditions. The A-frame (slanted roof) was comparatively advantageous over the conventional ...

  18. Rotating bending fatigue property of the Ni3Al-based single crystal superalloy IC6SX at 900°C

    Science.gov (United States)

    Jiang, Liwu; Li, Shusuo; Han, Yafang

    2017-03-01

    The high cycle fatigue behavior of a Ni3Al base single crystal superalloy IC6SX has been investigated at 900°C in this work. The specimens used for the fatigue tests were prepared by screw selection crystal method in a directional solidification furnace. The rotating bending fatigue tests were carried out at 900°Cin air, the stress ratio of R(σmax/σmin) was -1, and the rotating speed of the fatigue tests was 6500r/min(108Hz). The stress-fatigue cycle life (S-Nf) curve was obtained based on the fatigue tests, and the fracture surfaces were examined using scanning electron microscopy (SEM). It has been found that the median fatigue strength is 457.5MPa and the safety fatigue strength is 413.93MPa. And the fatigue fracture was composed of three different characteristic regions.

  19. A compounded rare-earth iron garnet single crystal exhibiting stable Faraday rotation against wavelength and temperature variation in the 1.55 μm band

    International Nuclear Information System (INIS)

    Xu, Z.C.; Huang, M.; Li Miao

    2006-01-01

    The Bi, Tb and Yb partially substituted iron garnet bulk single crystals of Tb 3- x - y Yb y Bi x Fe 5 O 12 were grown by using Bi 2 O 3 /B 2 O 3 as flux and accelerated crucible rotation technique for single-crystal growth. Faraday rotation (FR) spectra showed that the specific FR of the (Tb 0.91 Yb 1.38 Bi 0.71 )Fe 5 O 12 crystal under magnetic field at saturation was measured to be about -1617 o /cm at λ=1.55 μm, Faraday rotation wavelength coefficient (FWC, 0.009%/nm) in the wavelength range of 1.50-1.62 μm and Faraday rotation temperature coefficient (FTC, 3.92x10 -5 /K) at λ=1.55 μm were even smaller than that of YIG. It is proven that through combining two types of Bi-substituted rare-earth iron garnets with opposite FWC and FTC signs, the compound rare-earth iron garnets with low FWC and FTC may be obtained due to the compensation effect. The saturation magnetization of (Tb 0.91 Yb 1.38 Bi 0.71 ) Fe 5 O 12 crystal is 0.48x10 6 A/M and is also much smaller than that of YIG. We have found empirically that there is a simple relationship between the FR θ f (x) and Bi content x for Tb 3- x - y Yb y Bi x Fe 5 O 12 , which is given by θ f (x)=(-2759x+400) o /cm

  20. Triple-Loaded Single-Row Versus Suture-Bridge Double-Row Rotator Cuff Tendon Repair With Platelet-Rich Plasma Fibrin Membrane: A Randomized Controlled Trial.

    Science.gov (United States)

    Barber, F Alan

    2016-05-01

    To compare the structural healing and clinical outcomes of triple-loaded single-row with suture-bridging double-row repairs of full-thickness rotator cuff tendons when both repair constructs are augmented with platelet-rich plasma fibrin membrane. A prospective, randomized, consecutive series of patients diagnosed with full-thickness rotator cuff tears no greater than 3 cm in anteroposterior length were treated with a triple-loaded single-row (20) or suture-bridging double-row (20) repair augmented with platelet-rich plasma fibrin membrane. The primary outcome measure was cuff integrity by magnetic resonance imaging (MRI) at 12 months postoperatively. Secondary clinical outcome measures were American Shoulder and Elbow Surgeons, Rowe, Simple Shoulder Test, Constant, and Single Assessment Numeric Evaluation scores. The mean MRI interval was 12.6 months (range, 12-17 months). A total of 3 of 20 single-row repairs and 3 of 20 double-row repairs (15%) had tears at follow-up MRI. The single-row group had re-tears in 1 single tendon repair and 2 double tendon repairs. All 3 tears failed at the original attachment site (Cho type 1). In the double-row group, re-tears were found in 3 double tendon repairs. All 3 tears failed medial to the medial row near the musculotendinous junction (Cho type 2). All clinical outcome measures were significantly improved from the preoperative level (P plasma fibrin membrane. No difference could be demonstrated between these repairs on clinical outcome scores. I, Prospective randomized study. Copyright © 2016 Arthroscopy Association of North America. All rights reserved.

  1. Grey water treatment by the slanted soil system with unsorted soil media.

    Science.gov (United States)

    Ushijima, Ken; Tanaka, Erina; Suzuki, Laís Yuko; Hijikata, Nowaki; Funamizu, Naoyuki; Ito, Ryusei

    2015-01-01

    This study evaluated the performance of unsorted soil media in the slanted soil treatment system, in terms of removal efficiency in suspended solids (SS), chemical oxygen demand (COD), linear alkylbenzene sulphonate (LAS) and Escherichia coli, and lifetime until clogging occurs. Unsorted soil performed longer lifetime until clogging than sorted fine soil. Removal of SS, COD, and LAS also performed same or better level in unsorted soil than fine soil. As reaction coefficients of COD and LAS were described as a function of the hydraulic loading rate, we can design a slanted soil system according to the expected hydraulic loading rate and the targeted level of COD or LAS in effluent. Regarding bacteria removal, unsorted soil performed sufficient reduction of E. coli for 5 weeks; however, the removal process occurred throughout all four chambers, while that of fine soil occurred in one to two chambers.

  2. Nonlinear travelling waves in rotating Hagen–Poiseuille flow

    Science.gov (United States)

    Pier, Benoît; Govindarajan, Rama

    2018-03-01

    The dynamics of viscous flow through a rotating pipe is considered. Small-amplitude stability characteristics are obtained by linearizing the Navier–Stokes equations around the base flow and solving the resulting eigenvalue problems. For linearly unstable configurations, the dynamics leads to fully developed finite-amplitude perturbations that are computed by direct numerical simulations of the complete Navier–Stokes equations. By systematically investigating all linearly unstable combinations of streamwise wave number k and azimuthal mode number m, for streamwise Reynolds numbers {{Re}}z ≤slant 500 and rotational Reynolds numbers {{Re}}{{Ω }} ≤slant 500, the complete range of nonlinear travelling waves is obtained and the associated flow fields are characterized.

  3. Slant Path Distances Through Cells in Cylindrical Geometry and an Application to the Computation of Isophotes

    Energy Technology Data Exchange (ETDEWEB)

    Rodney Whitaker

    2007-12-17

    In computer programs involving two-dimensional cylindrical geometry, it is often necessary to calculate the slant path distance in a given direction from a point to the boundary of a mesh cell. A subroutine, HOWFAR, has been written that accomplishes this, and is very economical in computer time. An example of its use is given in constructing the isophotes for a low altitude nuclear fireball.

  4. Study of single pulsed-field magnetization of Gd-Ba-Cu-O bulk high-temperature superconductor with a split type of armature coil for rotating machinery

    International Nuclear Information System (INIS)

    Morita, E; Matsuzaki, H; Kimura, Y; Ohtani, I; Ogata, H; Izumi, M; Nonaka, Y; Murakami, M; Ida, T; Sugimoto, H; Miki, M; Kitano, M

    2006-01-01

    We employed a Gd-bulk HTS as rotating field magnet poles aiming for a smaller and lighter axial-gap-type motor. The bulk was inserted in the split-type armature pulsed copper coils and cooled down to 77 K under zero field. Employing the bulk magnet to HTS rotating machinery, the number of pulsed field magnetizations should be reduced for practical use. Thereby, a single pulsed current was applied to the pulsed copper coils to magnetize the bulk. The trapped field distribution and transient flux behaviour strongly depend on the radial dimension of the armature coil with a vortex-type winding. On decreasing the diameter of the pulsed copper armature coil, the distribution of the trapped flux density on the surface of the bulk becomes close to a conical shape. In contrast to the use of a solenoid, the application of vortex-type armature coils to magnetization of Gd-bulk HTS shows a quick intervention of the external magnetic flux into the centre of the bulk. The magnetization to the bulk HTS of the vortex-type copper coils with an optimum radius is useful and may be an effective technique for applied bulk HTS for rotating machines such as motors and/or generators

  5. Shear and foundation effects on crack root rotation and mode-mixity in moment- and force-loaded single cantilever beam sandwich specimen

    DEFF Research Database (Denmark)

    Saseendran, Vishnu; Carlsson, Leif A.; Berggreen, Christian

    2017-01-01

    Foundation effects play a crucial role in sandwich fracture specimens with a soft core. Accurate estimation of deformationcharacteristics at the crack front is vital in understanding compliance, energy release rate and mode-mixity infracture test specimens. Beam on elastic foundation analysis...... beam specimen (in contrast to themoment-loaded case), it was found that the crack length normalized energy release rate and the mode-mixity phaseangle increase strongly as the crack length decreases, a result of increased dominance of shear loading....... of moment- and force-loaded single cantilever beam sandwichfracture specimens is presented here. In addition, finite element analysis of the single cantilever beam specimen isconducted to determine displacements, rotations, energy release rate and mode-mixity. Based on finite element analysis,a foundation...

  6. Muon spin rotation study of magnetism and superconductivity in Ba(Fe1-xCox)2As2 single crystals

    DEFF Research Database (Denmark)

    Bernhard, C.; Wang, C. N.; Nuccio, L.

    2012-01-01

    Using muon spin rotation (μSR) we investigated the magnetic and superconducting properties of a series of Ba(Fe1−xCox)2As2 single crystals with 0 ≤x ≤0.15. Our study details how the antiferromagnetic order is suppressed upon Co substitution and how it coexists with superconductivity. In the nonsu......Using muon spin rotation (μSR) we investigated the magnetic and superconducting properties of a series of Ba(Fe1−xCox)2As2 single crystals with 0 ≤x ≤0.15. Our study details how the antiferromagnetic order is suppressed upon Co substitution and how it coexists with superconductivity...... caused by the randomly distributed Co atoms. A different kind of magnetic order that was also previously identified [C. Bernhard et al., New J. Phys. 11, 055050 (2009)] occurs at 0.055 magnetic order develops here only in parts of the sample volume...... and it seems to cooperate with superconductivity since its onset temperature coincides with Tc. Even in the strongly overdoped regime at x = 0.11, where the static magnetic order has disappeared, we find that the low-energy spin fluctuations are anomalously enhanced below Tc. These findings point toward...

  7. Percutaneous peripheral rotational ablation using the Rotablator: immediate and mid term results. Single center experience concerning 146 lesions treated.

    Science.gov (United States)

    Henry, M; Amor, M; Ethevenot, G; Henry, I

    1993-09-01

    In order to assess the role of percutaneous peripheral rotational ablation using Rotablator (PPRA), 95 symptomatic patients (58 M, 37 F, m. age: 77 +/- 1 y) (r: 50-90 y) having 146 peripheral vascular lesions (PVL) were treated by PPRA. 59% were below the knee and 41% above. The runoff status (n of distal leg art. involved) was as follows: 3:52 pts, 2:23 pts, 1:14 pts, 0:6 pts. The femoral lesions were significantly longer than those at other sites (5.27 +/- 0.43 vs 2.97 +/- 0.3 cm) (p Pop) than in distal leg lesions (10/86.). RESULTS. After PPRA alone (99 PVL) the stenosis % decreased from 81 +/- 0.75 to 18 +/- 1.1. The residual stenosis was greater at femoral (26 +/- 2.3%) than at distal leg level (16 +/- 1.2%) (p or = 4 mths, 74 pts representing 115 treated PVL underwent an angiography control (2 deaths, 2 lost for follow-up). 87 lesions (76%) showed no restenosis and 28 lesions (34%) showed restenosis of 83 +/- 2.4% (r: 50-100%). The restenosis rate was higher in femoral (12/21: 36%) than in distal (15/58: 21%) or popliteal arteries (1/8: 12%). Restenosis was more frequent for PVL > or = 7 cm (67% vs 16%) (p or = 6.7 cm would be a limitation for PPRA. CONCLUSIONS. In our experience Percutaneous Peripheral Rotational Ablation has taken a pre-eminent position in the treatment of distal leg arteries. Our results lead us to broaden its indications to complex vascular lesions. The possibility of runoff treatment should allow an improvement in the long-term patency of PTA and bypass grafts.

  8. Single photon imaging. New instrumentation and techniques

    International Nuclear Information System (INIS)

    Muehllehner, G.; Colsher, J.

    1981-01-01

    The performance of Anger scintillation cameras continues to be enhanced through a series of small improvements which result in significantly better imaging characteristics. The most recent changes in camera design consist of: (1) the introduction of photomultipliers with better photocathode and electron collection efficiencies, (2) the use of thinner (3/8 or 1/4 in) crystals giving slightly better intrinsic resolution for low gamma-ray energies, (3) inclusion of a spatially varying energy window to compensate for variations of light collection efficiency, (4) event-by-event, real-time distortion removal for uniformity correction, and (5) introduction of new methods to improve the count-rate capability. Whereas some of these improvements are due to better understanding of the fundamentals of camera design, others are the result of technological advances in electronic components such as analogue-to-digital converters, microprocessors and high-density digital memories. The development of single photon tomography has developed along two parallel paths. Multipinhole and rotating slant-hole collimator attachments provide some degree of longitudinal tomography, and are currently being applied to cardiac imaging. At the same time rotating camera systems capable of transverse as well as longitudinal imaging are being refined technically and evaluated clinically. Longitudinal tomography is of limited use in quantitative studies and is likely to be an interim solution to three-dimensional imaging. Rotating camera systems, on the other hand, not only provide equal resolution in all three dimensions but are also capable of providing quantitative accuracy. This is the result of progress in attenuation correction and the design of special collimators. Single photon tomography provides a small but noticeable improvement in diagnostic accuracy which is likely to result in widespread use of rotating camera systems in the future

  9. MAX-DOAS formaldehyde slant column measurements during CINDI: intercomparison and analysis improvement

    Directory of Open Access Journals (Sweden)

    G. Pinardi

    2013-01-01

    Full Text Available We present intercomparison results for formaldehyde (HCHO slant column measurements performed during the Cabauw Intercomparison campaign of Nitrogen Dioxide measuring Instruments (CINDI that took place in Cabauw, the Netherlands, in summer 2009. During two months, nine atmospheric research groups simultaneously operated MAX-DOAS (MultiAXis Differential Optical Absorption Spectroscopy instruments of various designs to record UV-visible spectra of scattered sunlight at different elevation angles that were analysed using common retrieval settings. The resulting HCHO data set was found to be highly consistent, the mean difference between instruments generally not exceeding 15% or 7.5 × 1015 molec cm−2, for all viewing elevation angles. Furthermore, a sensitivity analysis was performed to investigate the uncertainties in the HCHO slant column retrieval when varying key input parameters such as the molecular absorption cross sections, correction terms for the Ring effect or the width and position of the fitting interval. This study led to the identification of potentially important sources of errors associated with cross-correlation effects involving the Ring effect, O4, HCHO and BrO cross sections and the DOAS closure polynomial. As a result, a set of updated recommendations was formulated for HCHO slant column retrieval in the 336.5–359 nm wavelength range. To conclude, an error budget is proposed which distinguishes between systematic and random uncertainties. The total systematic error is estimated to be of the order of 20% and is dominated by uncertainties in absorption cross sections and related spectral cross-correlation effects. For a typical integration time of one minute, random uncertainties range between 5 and 30%, depending on the noise level of individual instruments.

  10. Mobile display backlight light guide plates based on slanted grating arrays

    Science.gov (United States)

    Kimmel, Jyrki; Levola, Tapani

    2011-05-01

    Modern mobile communication devices have user interfaces that are dominated by high-quality displays. Increased multimedia use imposes high demands on the design of display modules, as the content available for mobile use becomes visually richer. Especially the power dissipation of the display can limit the amount of time available for multimedia consumption and interaction. In the mobile liquid-crystal display (LCD), the energy efficiency is determined by the backlight design. State-of-the-art backlights direct white light through a display subpixel array, with high uniformity and up to 90 % efficiency in white light output. Diffractive backlights have recently been proposed to reduce the power dissipation of the display module, and slanted grating arrays are among the enabling optical features that allow for reduction in power dissipation beyond what is available in the state of the art. By the use of diffractive grating arrays, the required primary color (red, green, or blue) is directed through the LCD subpixel array with geometrical registration, instead of flooding the whole LCD with white light and filtering the primary colors through the subpixel color filter array. This paper presents a study on grating structures based on slanted grating arrays fabricated in high refractive index materials. The grating design and grating outcoupling results are provided, and an outline of a new embedded system design is given. Emphasis is on grating array design aspects for future display system design. The results show that savings in power consumption can be expected with advanced display system design based on embedded slanted grating array backlight light guide plates.

  11. Identifying Z-axis gyro drift and scale factor error using azimuth measurement in fiber optic gyroscope single-axis rotation inertial navigation system

    Science.gov (United States)

    Wang, Lingcao; Li, Kui; Wang, Lei; Gao, Jiaxin

    2017-02-01

    In the fiber optic gyroscope (FOG) single-axis rotation inertial navigation system (SRINS), the Z-axis gyro drift (ɛz) dramatically limits its navigation precision and the Z-axis gyro scale factor error (δK) can cause greater navigation error because of the rotation process compared with the strap-down inertial navigation system. Hence, identification and compensation for the ɛz and δK are important in SRINS. An approach based on the azimuth error model of open-loop algorithm is proposed. This approach considers azimuth angle as a measurement and uses a least recursive square algorithm for identifying the ɛz and δK. Compared with the traditional method, which takes velocity and position errors as measurements, the time required for identifying ɛz with the proposed method is only approximately 10 min, while the traditional method requires 6 h to 12 h. Experimental results from an SRINS with FOGs demonstrate that the accuracy of identifying the ɛz reaches 0.002°/h and that of the δK reaches 8 ppm in 10 min. The positioning accuracy of the SRINS improves greatly after the identification and compensation.

  12. Characterization and comparison of three microfabrication methods to generate out-of-plane microvortices for single cell rotation and 3D imaging

    International Nuclear Information System (INIS)

    Shetty, Rishabh M; Myers, Jakrey R; Sreenivasulu, Manoj; Teller, Wacey; Vela, Juan; Houkal, Jeff; Chao, Shih-Hui; Johnson, Roger H; Kelbauskas, Laimonas; Wang, Hong; Meldrum, Deirdre R

    2017-01-01

    This paper presents three different microfabrication technologies for manufacturing out-of-plane, flat-bottomed, undercut trapezoidal structures for generating a fluidic microscale vortex (microvortex). The first method is based on anisotropic silicon etching and a ‘sandwich’ UV polymer casting assembly; the second method uses a backside diffuser photolithography technique; and the third method features a tilted backside photolithography technique. We discuss the advantages, limitations, and utility of each technique. We further demonstrate that the microvortex generated in the resultant undercut trapezoidal structures can be used to rotate biological microparticles, e.g. single, live cells for multiperspective, high resolution 3D imaging using computed tomography, and angularly resolved confocal imaging. (paper)

  13. dSPACE real time implementation of fuzzy PID position controller for vertical rotating single link arm robot using four-quadrant BLDC drive

    Directory of Open Access Journals (Sweden)

    Manikandan Ramasamy

    2017-07-01

    Full Text Available Automation has been growing in recent years for the manufacturing industries to increase productivity. Multiple robotic arms are used to handle materials for lifting in flexible directions. The vertical rotation of a 360 degree single arm is considered in this research on a position servo drive with brushless DC motor. The load torque of an arm varies depending upon the angular displacement due to gravity, so it requires four-quadrant operation of the drive with a robust feedback controller. This paper deals with the design and performance comparison of a conventional PID feedback controller with a fuzzy-based PID controller and suggests the most suitable controller. The design was implemented in real time through the dSPACE DS1104 controller environment to verify the dynamic behaviors of the arm.

  14. Steady-state response of a geared rotor system with slant cracked shaft and time-varying mesh stiffness

    Science.gov (United States)

    Han, Qinkai; Zhao, Jingshan; Lu, Wenxiu; Peng, Zhike; Chu, Fulei

    2014-04-01

    The dynamic behavior of geared rotor system with defects is helpful for the failure diagnosis and state detecting of the system. Extensive efforts have been devoted to study the dynamic behaviors of geared systems with tooth root cracks. When surface cracks (especially for slant cracks) appear on the transmission shaft, the dynamic characteristics of the system have not gained sufficient attentions. Due to the parametric excitations induced by slant crack breathing and time-varying mesh stiffness, the steady-state response of the cracked geared rotor system differs distinctly from that of the uncracked system. Thus, utilizing the direct spectral method (DSM), the forced response spectra of a geared rotor system with slant cracked shaft and time-varying mesh stiffness under transmission error, unbalance force and torsional excitations are, respectively, obtained and discussed in detail. The effects of crack types (straight or slant crack) and crack depth on the forced response spectra of the system without and with torsional excitation are considered in the analysis. In addition, how the frequency response characteristics change after considering the crack is also investigated. It is shown that the torsional excitations have significant influence on the forced response spectra of slant cracked system. Sub-critical resonances are also found in the frequency response curves. The results could be used for shaft crack detection in geared rotor system.

  15. A self-managed single exercise programme versus usual physiotherapy treatment for rotator cuff tendinopathy: a randomised controlled trial (the SELF study).

    Science.gov (United States)

    Littlewood, Chris; Bateman, Marcus; Brown, Kim; Bury, Julie; Mawson, Sue; May, Stephen; Walters, Stephen J

    2016-07-01

    To evaluate the clinical effectiveness of a self-managed single exercise programme versus usual physiotherapy treatment for rotator cuff tendinopathy. Multi-centre pragmatic unblinded parallel group randomised controlled trial. UK National Health Service. Patients with a clinical diagnosis of rotator cuff tendinopathy. The intervention was a programme of self-managed exercise prescribed by a physiotherapist in relation to the most symptomatic shoulder movement. The control group received usual physiotherapy treatment. The primary outcome measure was the Shoulder Pain & Disability Index (SPADI) at three months. Secondary outcomes included the SPADI at six and twelve months. A total of 86 patients (self-managed loaded exercise n=42; usual physiotherapy n=44) were randomised. Twenty-six patients were excluded from the analysis because of lack of primary outcome data at the 3 months follow-up, leaving 60 (n=27; n=33) patients for intention to treat analysis. For the primary outcome, the mean SPADI score at three months was 32.4 (SD 20.2) for the self-managed group, and 30.7 (SD 19.7) for the usual physiotherapy treatment group; mean difference adjusted for baseline score: 3.2 (95% Confidence interval -6.0 to +12.4 P = 0.49).By six and twelve months there remained no significant difference between the groups. This study does not provide sufficient evidence of superiority of one intervention over the other in the short-, mid- or long-term and hence a self-management programme based around a single exercise appears comparable to usual physiotherapy treatment. © The Author(s) 2015.

  16. Evaluation of apical extrusion of debris and irrigant using two new reciprocating and one continuous rotation single file systems.

    Directory of Open Access Journals (Sweden)

    Gurudutt Nayak

    2014-06-01

    Full Text Available Apical extrusion of debris and irrigants during cleaning and shaping of the root canal is one of the main causes of periapical inflammation and postoperative flare-ups. The purpose of this study was to quantitatively measure the amount of debris and irrigants extruded apically in single rooted canals using two reciprocating and one rotary single file nickel-titanium instrumentation systems.Sixty human mandibular premolars, randomly assigned to three groups (n = 20 were instrumented using two reciprocating (Reciproc and Wave One and one rotary (One Shape single-file nickel-titanium systems. Bidistilled water was used as irrigant with traditional needle irrigation delivery system. Eppendorf tubes were used as test apparatus for collection of debris and irrigant. The volume of extruded irrigant was collected and quantified via 0.1-mL increment measure supplied on the disposable plastic insulin syringe. The liquid inside the tubes was dried and the mean weight of debris was assessed using an electronic microbalance. The data were statistically analysed using Kruskal-Wallis nonparametric test and Mann Whitney U test with Bonferroni adjustment. P-values less than 0.05 were considered significant.The Reciproc file system produced significantly more debris compared with OneShape file system (P0.05. Extrusion of irrigant was statistically insignificant irrespective of the instrument or instrumentation technique used (P >0.05.Although all systems caused apical extrusion of debris and irrigant, continuous rotary instrumentation was associated with less extrusion as compared with the use of reciprocating file systems.

  17. Internal Flow of a High Specific-Speed Diagonal-Flow Fan (Rotor Outlet Flow Fields with Rotating Stall

    Directory of Open Access Journals (Sweden)

    Norimasa Shiomi

    2003-01-01

    Full Text Available We carried out investigations for the purpose of clarifying the rotor outlet flow fields with rotating stall cell in a diagonal-flow fan. The test fan was a high–specific-speed (ns=1620 type of diagonal-flow fan that had 6 rotor blades and 11 stator blades. It has been shown that the number of the stall cell is 1, and its propagating speed is approximately 80% of its rotor speed, although little has been known about the behavior of the stall cell because a flow field with a rotating stall cell is essentially unsteady. In order to capture the behavior of the stall cell at the rotor outlet flow fields, hot-wire surveys were performed using a single-slant hotwire probe. The data obtained by these surveys were processed by means of a double phase-locked averaging technique, which enabled us to capture the flow field with the rotating stall cell in the reference coordinate system fixed to the rotor. As a result, time-dependent ensemble averages of the three-dimensional velocity components at the rotor outlet flow fields were obtained. The behavior of the stall cell was shown for each velocity component, and the flow patterns on the meridional planes were illustrated.

  18. Perception of Stand-on-ability: Do Geographical Slants Feel Steeper Than They Look?

    Science.gov (United States)

    Hajnal, Alen; Wagman, Jeffrey B; Doyon, Jonathan K; Clark, Joseph D

    2016-07-01

    Past research has shown that haptically perceived surface slant by foot is matched with visually perceived slant by a factor of 0.81. Slopes perceived visually appear shallower than when stood on without looking. We sought to identify the sources of this discrepancy by asking participants to judge whether they would be able to stand on an inclined ramp. In the first experiment, visual perception was compared to pedal perception in which participants took half a step with one foot onto an occluded ramp. Visual perception closely matched the actual maximal slope angle that one could stand on, whereas pedal perception underestimated it. Participants may have been less stable in the pedal condition while taking half a step onto the ramp. We controlled for this by having participants hold onto a sturdy tripod in the pedal condition (Experiment 2). This did not eliminate the difference between visual and haptic perception, but repeating the task while sitting on a chair did (Experiment 3). Beyond balance requirements, pedal perception may also be constrained by the limited range of motion at the ankle and knee joints while standing. Indeed, when we restricted range of motion by wearing an ankle brace pedal perception underestimated the affordance (Experiment 4). Implications for ecological theory were offered by discussing the notion of functional equivalence and the role of exploration in perception. © The Author(s) 2016.

  19. Two memories for geographical slant: separation and interdependence of action and awareness

    Science.gov (United States)

    Creem, S. H.; Proffitt, D. R.; Kaiser, M. K. (Principal Investigator)

    1998-01-01

    The present study extended previous findings of geographical slant perception, in which verbal judgments of the incline of hills were greatly overestimated but motoric (haptic) adjustments were much more accurate. In judging slant from memory following a brief or extended time delay, subjects' verbal judgments were greater than those given when viewing hills. Motoric estimates differed depending on the length of the delay and place of response. With a short delay, motoric adjustments made in the proximity of the hill did not differ from those evoked during perception. When given a longer delay or when taken away from the hill, subjects' motoric responses increased along with the increase in verbal reports. These results suggest two different memorial influences on action. With a short delay at the hill, memory for visual guidance is separate from the explicit memory informing the conscious response. With short or long delays away from the hill, short-term visual guidance memory no longer persists, and both motor and verbal responses are driven by an explicit representation. These results support recent research involving visual guidance from memory, where actions become influenced by conscious awareness, and provide evidence for communication between the "what" and "how" visual processing systems.

  20. Asymmetric liquid wetting and spreading on surfaces with slanted micro-pillar arrays

    KAUST Repository

    Yang, Xiaoming

    2013-01-01

    Uni-directional liquid spreading on asymmetric silicone-fabricated nanostructured surfaces has recently been reported. In this work, uniformly deflected polydimethylsiloxane (PDMS) micro-pillars covered with silver films were fabricated. Asymmetric liquid wetting and spreading behaviors in a preferential direction were observed on the slanted micro-pillar surfaces and a micro-scale thin liquid film advancing ahead of the bulk liquid droplet was clearly observed by high-speed video imaging. It is found that the slanted micro-pillar array is able to promote or inhibit the propagation of this thin liquid film in different directions by the asymmetric capillary force. The spreading behavior of the bulk liquid was guided and finally controlled by this micro-scale liquid film. Different spreading regimes are defined by the relationship between the liquid intrinsic contact angle and the critical angles, which were determined by the pillar height, pillar deflection angle and inter-pillar spacing. © The Royal Society of Chemistry 2013.

  1. Rotational seismology

    Science.gov (United States)

    Lee, William H K.

    2016-01-01

    Rotational seismology is an emerging study of all aspects of rotational motions induced by earthquakes, explosions, and ambient vibrations. It is of interest to several disciplines, including seismology, earthquake engineering, geodesy, and earth-based detection of Einstein’s gravitation waves.Rotational effects of seismic waves, together with rotations caused by soil–structure interaction, have been observed for centuries (e.g., rotated chimneys, monuments, and tombstones). Figure 1a shows the rotated monument to George Inglis observed after the 1897 Great Shillong earthquake. This monument had the form of an obelisk rising over 19 metres high from a 4 metre base. During the earthquake, the top part broke off and the remnant of some 6 metres rotated about 15° relative to the base. The study of rotational seismology began only recently when sensitive rotational sensors became available due to advances in aeronautical and astronomical instrumentations.

  2. MUSCLE ACTIVITY RESPONSE TO EXTERNAL MOMENT DURING SINGLE-LEG DROP LANDING IN YOUNG BASKETBALL PLAYERS: THE IMPORTANCE OF BICEPS FEMORIS IN REDUCING INTERNAL ROTATION OF KNEE DURING LANDING

    Directory of Open Access Journals (Sweden)

    Meguru Fujii

    2012-06-01

    Full Text Available Internal tibial rotation with the knee close to full extension combined with valgus collapse during drop landing generally results in non-contact anterior cruciate ligament (ACL injury. The purpose of this study was to investigate the relationship between internal rotation of the knee and muscle activity from internal and external rotator muscles, and between the internal rotation of knee and externally applied loads on the knee during landing in collegiate basketball players. Our hypothesis was that the activity of biceps femoris muscle would be an important factor reducing internal knee rotation during landing. The subjects were 10 collegiate basketball students: 5 females and 5 males. The subjects performed a single-leg drop landing from a 25-cm height. Femoral and tibial kinematics were measured using a 3D optoelectronic tracking system during the drop landings, and then the knee angular motions were determined. Ground reaction forces and muscle activation patterns (lateral hamstring and medial hamstring were simultaneously measured and computed. Results indicated that lower peak internal tibial rotation angle at the time of landing was associated with greater lateral hamstring activity (r = -0.623, p < 0.001. When gender was considered, the statistically significant correlation remained only in females. There was no association between the peak internal tibial rotation angle and the knee internal rotation moment. Control of muscle activity in the lateral to medial hamstring would be an important factor in generating sufficient force to inhibit excessive internal rotation during landing. Strengthening the biceps femoris might mitigate the higher incidence of non-contact ACL injury in female athletes

  3. From slant column densities to trace gas profiles: Post processing data from the new MAX-DOAS network in Mexico City

    Science.gov (United States)

    Friedrich, M. M.; Stremme, W.; Rivera, C. I.; Arellano, E. J.; Grutter, M.

    2014-12-01

    The new MAX-DOAS network in Mexico City provides results of O4, HCHO and NO2 slant column densities (SCD). Here, we present a new numerical code developed to retrieve gas profiles of NO2 and HCHO using radiative transfer simulations. We present first results of such profiles from the MAX-DOAS station located at UNAM campus. The code works in two steps: First, the O4 slant column density information is used to retrieve an aerosol profile. As an a-priori aerosol profile, we use averaged ceilometer data measured at UNAM and scaled to the total optical depth provided by the Aeronet data base. In the second step, the retrieved aerosol profile information is used together with the trace gas (HCHO or NO2) SCDs to retrieve the trace gas profiles. The inversion is based on a gauss-newton iteration scheme and uses constrained least square fitting with either optimal estimation or Tihkonov regularization. For the latter, the regulation matrix is currently constructed from the discrete first derivative operator. The forward model uses the radiative transfer code VLIDORT. The inputs to VLIDORT are calculated using temperature and pressure information from daily radiosounde measurements and aerosol single scattering optical depths and asymmetry factors from the Aeronet data base for Mexico City. For the gas absorption cross sections we use the same values as were used for the SCD calculation from the recorded spectra using QDOAS. Besides demonstrating the functionality of the algorithm showing profile retrievals of simulated SCDs with added random noise, we present HCHO and NO2 profiles retrieved from SCDs calculated from the MAX-DOAS measurements at UNAM campus at selected days.

  4. The slant of the forehead as a craniofacial feature of impulsiveness

    Directory of Open Access Journals (Sweden)

    J. David Guerrero-Apolo

    2018-03-01

    Full Text Available Objective: Impulsiveness has been the subject of much research, but little is known about the possible relationship between craniofacial anatomy and impulsiveness. The present study was designed to investigate the relationship between one aspect of craniofacial structure (the angle of inclination of the forehead and impulsiveness. Method: Photographs in profile were obtained from 131 volunteers who had been fined for driving at high speed and were undergoing a court-mandated driving license point-recovery course. They completed the Barratt Impulsiveness Scale (BIS-11, the Impulsive Behavior Scale (UPPS-P, and Zuckerman’s Sensation Seeking Scale (V. The angle of the slant of the forehead was measured with a photographic support and a protractor. Results: High positive concordance was found between forehead inclination and 14 out of the 15 impulsiveness factors studied. Conclusions: The angle of inclination of the forehead was significantly associated with self-reported impulsiveness in this sample of traffic violators.

  5. Structural and optical properties of cobalt slanted nanopillars conformally coated with few-layer graphene

    Science.gov (United States)

    Wilson, Peter M.; Lipatov, Alexey; Schmidt, Daniel; Schubert, Eva; Schubert, Mathias; Sinitskii, Alexander; Hofmann, Tino

    2015-06-01

    Optical characterization of anisotropic multicomponent nanostructures is generally not a trivial task, since the relation between a material's structural properties and its permittivity tensor is nonlinear. In this regard, an array of slanted cobalt nanopillars that are conformally coated with few-layer graphene is a particularly challenging object for optical characterization, as it has a complex anisotropic geometry and comprises several materials with different topologies and filling fractions. Normally, a detailed characterization of such complex nanostructures would require a combination of several microscopic and spectroscopic techniques. In this letter, we demonstrate that the important structural parameters of these graphene-coated sculptured thin films can be determined using a fast and simple generalized spectroscopic ellipsometry test combined with an anisotropic Bruggeman effective medium approximation. The graphene coverage as well as structural parameters of nanostructured thin films agree excellently with electron microscopy and Raman spectroscopy observations. The demonstrated optical approach may also be applied to the characterization of other nanostructured materials.

  6. Global rotation

    International Nuclear Information System (INIS)

    Rosquist, K.

    1980-01-01

    Global rotation in cosmological models is defined on an observational basis. A theorem is proved saying that, for rigid motion, the global rotation is equal to the ordinary local vorticity. The global rotation is calculated in the space-time homogeneous class III models, with Godel's model as a special case. It is shown that, with the exception of Godel's model, the rotation in these models becomes infinite for finite affine parameter values. In some directions the rotation changes sign and becomes infinite in a direction opposite to the local vorticity. The points of infinite rotation are identified as conjugate points along the null geodesics. The physical interpretation of the infinite rotation is discussed, and a comparison with the behaviour of the area distance at conjugate points is given. (author)

  7. Slant Wet Delays from GNSS observations - Precise Point Positioning vs. Double Difference Approach

    Science.gov (United States)

    Moeller, Gregor; Weber, Robert

    2015-04-01

    The tropospheric parameter SWD (Slant Wet Delay) is the path delay caused by the highly variable amount of humidity in the atmosphere at altitudes below 12 km. It can be derived from Numerical Weather Predication data or even more precisely from dual- or multi-frequency observations of a regional GNSS reference network. In order to find the most adequate processing strategy dual GNSS observations of a small network of reference stations were simulated and tropospheric parameters were estimated in Precise Point Positioning (PPP) and in Double Difference (DD) mode. In DD mode the integer character of the phase ambiguities remains which allows to fix them to their true values and to obtain the tropospheric zenith delay as well as north and east (N/E) gradients with highest precision over very short time periods. In PPP mode orbit and clock errors are not cancelled out which affects the quality of the tropospheric estimates. On the other hand it has the advantage that the GNSS observations are processed undifferenced. Latter is important because the Zero Difference Residuals (ZDR) contain the azimuthal-anisotropic part of the tropospheric delay which is not covered by the estimated parameters. From Double Difference Residuals (DDR) the ZDR can be recovered too but only conditionally since common tropospheric effects have been cancelled out in advance by differencing. In this presentation we show how good the anisotropic slant path delays can be obtained from GNSS observations processed using both concepts - the PPP and the DD approach. Therefore tropospheric zenith delays and N/E gradients were estimated and Pseudo-ZDR were reconstructed from DDR and afterwards compared with ZDR derived from the PPP solution. In addition it is shown how good both concepts are applicable for observations at very low elevation angles and under extreme weather conditions. The IGS final and ultra-rapid service products were taken into account to define the best strategy not only for post

  8. Dual-Axis Rotational Angiography is Safe and Feasible to Detect Coronary Allograft Vasculopathy in Pediatric Heart Transplant Patients: A Single-Center Experience.

    Science.gov (United States)

    Rios, Rodrigo; Loomba, Rohit S; Foerster, Susan R; Pelech, Andrew N; Gudausky, Todd M

    2016-04-01

    Coronary allograft vasculopathy (CAV) is the leading cause of graft failure in pediatric heart transplant recipients, also adding to mortality in this patient population. Coronary angiography is routinely performed to screen for CAV, with conventional single-plane or bi-plane angiography being utilized. Dual-axis rotational coronary angiography (RA) has been described, mostly in the adult population, and may offer reduction in radiation dose and contrast volume. Experience with this in the pediatric population is limited. This study describes a single-institution experience with RA for screening for CAV in pediatric patients. The catheterization database at our institution was used to identify pediatric heart transplant recipients having undergone RA to screen for CAV. Procedural data including radiation dose, fluoroscopy time, contrast volume, and procedure time were collected for each catheterization. The number of instances in which RA was not successful, ECG changes were present, and CAV was detected were also collected for each catheterization. A total of 97 patients underwent 345 catheterizations utilizing RA. Median radiation dose-area product per kilogram was found to be 341.7 (mGy cm(2)/kg), total air kerma was 126.8 (mGy), procedure time was 69 min, fluoroscopy time was 9.9 min, and contrast volume was 13 ml. A total of 17 (2 %) coronary artery injections out of 690 could not be successfully imaged using RA. A total of 14 patients had CAV noted at any point, 10 of whom had progressive CAV. Electrocardiographic changes were documented in a total of 10 (3 %) RA catheterizations. Procedural characteristics did not differ between serial catheterizations. RA is safe and feasible for CAV screening in pediatric heart transplant recipients while offering coronary imaging in multiple planes compared to conventional angiography.

  9. Coherent spin-rotational dynamics of oxygen superrotors

    Science.gov (United States)

    Milner, Alexander A.; Korobenko, Aleksey; Milner, Valery

    2014-09-01

    We use state- and time-resolved coherent Raman spectroscopy to study the rotational dynamics of oxygen molecules in ultra-high rotational states. While it is possible to reach rotational quantum numbers up to N≈ 50 by increasing the gas temperature to 1500 K, low population levels and gas densities result in correspondingly weak optical response. By spinning {{O}2} molecules with an optical centrifuge, we efficiently excite extreme rotational states with N≤slant 109 in high-density room temperature ensembles. Fast molecular rotation results in the enhanced robustness of the created rotational wave packets against collisions, enabling us to observe the effects of weak spin-rotation coupling in the coherent rotational dynamics of oxygen. The decay rate of spin-rotational coherence due to collisions is measured as a function of the molecular angular momentum and its dependence on the collisional adiabaticity parameter is discussed. We find that at high values of N, the rotational decoherence of oxygen is much faster than that of the previously studied non-magnetic nitrogen molecules, pointing at the effects of spin relaxation in paramagnetic gases.

  10. An Investigation of Single- and Dual-Rotation Propellers at Positive and Negative Thrust, and in Combination with an NACA 1-series D-Type Cowling at Mach Numbers up to 0.84

    Science.gov (United States)

    Reynolds, Robert M; Samonds, Robert I; Walker, John H

    1957-01-01

    An investigation has been made to determine the aerodynamic characteristics of the NACA 4-(5)(05)-041 four-blade, single-relation propeller and the NACA 4-(5)(05)-037 six- and eight-blade, dual-rotation propellers in combination with various spinners and NACA d-type spinner-cowling combinations at Mach numbers up to 0.84. Propeller force characteristics, local velocity distributions in the propeller planes, inlet pressure recoveries, and static-pressure distributions on the cowling surfaces were measured for a wide range of blade angles, advance ratios, and inlet-velocity ratios. Included are data showing: (a) the effect of extended cylindrical spinners on the characteristics of the single-rotation propeller, (b) the effect of variation of the difference in blade angle setting between the front and rear components of the dual-rotation propellers, (c) the negative- and static-thrust characteristics of the propellers with 1 series spinners, and (d) the effects of ideal- and platform-type propeller-spinner junctures on the pressure-recovery characteristics of the single-rotation propeller-spinner-cowling combination.

  11. Rotating Wavepackets

    Science.gov (United States)

    Lekner, John

    2008-01-01

    Any free-particle wavepacket solution of Schrodinger's equation can be converted by differentiations to wavepackets rotating about the original direction of motion. The angular momentum component along the motion associated with this rotation is an integral multiple of [h-bar]. It is an "intrinsic" angular momentum: independent of origin and…

  12. The rotator

    DEFF Research Database (Denmark)

    Jensen, Eva B. Vedel; Gundersen, Hans Jørgen Gottlieb

    1993-01-01

    The mean particle volume can be stereologically estimated using the nucleator principle. In the present paper, we discuss another principle for estimating mean particle volume, namely the rotator. The vertical rotator has already been previously described and is supplemented in the present paper ...

  13. Rotational elasticity

    Science.gov (United States)

    Vassiliev, Dmitri

    2017-04-01

    We consider an infinite three-dimensional elastic continuum whose material points experience no displacements, only rotations. This framework is a special case of the Cosserat theory of elasticity. Rotations of material points are described mathematically by attaching to each geometric point an orthonormal basis that gives a field of orthonormal bases called the coframe. As the dynamical variables (unknowns) of our theory, we choose the coframe and a density. We write down the general dynamic variational functional for our rotational theory of elasticity, assuming our material to be physically linear but the kinematic model geometrically nonlinear. Allowing geometric nonlinearity is natural when dealing with rotations because rotations in dimension three are inherently nonlinear (rotations about different axes do not commute) and because there is no reason to exclude from our study large rotations such as full turns. The main result of the talk is an explicit construction of a class of time-dependent solutions that we call plane wave solutions; these are travelling waves of rotations. The existence of such explicit closed-form solutions is a non-trivial fact given that our system of Euler-Lagrange equations is highly nonlinear. We also consider a special case of our rotational theory of elasticity which in the stationary setting (harmonic time dependence and arbitrary dependence on spatial coordinates) turns out to be equivalent to a pair of massless Dirac equations. The talk is based on the paper [1]. [1] C.G.Boehmer, R.J.Downes and D.Vassiliev, Rotational elasticity, Quarterly Journal of Mechanics and Applied Mathematics, 2011, vol. 64, p. 415-439. The paper is a heavily revised version of preprint https://arxiv.org/abs/1008.3833

  14. Methodology and consistency of slant and vertical assessments for ionospheric electron content models

    Science.gov (United States)

    Hernández-Pajares, Manuel; Roma-Dollase, David; Krankowski, Andrzej; García-Rigo, Alberto; Orús-Pérez, Raül

    2017-12-01

    A summary of the main concepts on global ionospheric map(s) [hereinafter GIM(s)] of vertical total electron content (VTEC), with special emphasis on their assessment, is presented in this paper. It is based on the experience accumulated during almost two decades of collaborative work in the context of the international global navigation satellite systems (GNSS) service (IGS) ionosphere working group. A representative comparison of the two main assessments of ionospheric electron content models (VTEC-altimeter and difference of Slant TEC, based on independent global positioning system data GPS, dSTEC-GPS) is performed. It is based on 26 GPS receivers worldwide distributed and mostly placed on islands, from the last quarter of 2010 to the end of 2016. The consistency between dSTEC-GPS and VTEC-altimeter assessments for one of the most accurate IGS GIMs (the tomographic-kriging GIM `UQRG' computed by UPC) is shown. Typical error RMS values of 2 TECU for VTEC-altimeter and 0.5 TECU for dSTEC-GPS assessments are found. And, as expected by following a simple random model, there is a significant correlation between both RMS and specially relative errors, mainly evident when large enough number of observations per pass is considered. The authors expect that this manuscript will be useful for new analysis contributor centres and in general for the scientific and technical community interested in simple and truly external ways of validating electron content models of the ionosphere.

  15. Towards 2D field-flow fractionation - Vector separation over slanted open cavities

    Science.gov (United States)

    Bernate, Jorge A.; Yang, Mengfei; Zhao, Hong; Risbud, Sumedh; Paul, Colin; Dallas, Matthew; Konstantopoulos, Konstantinos; Drazer, German; Shaqfeh, Eric S. G.

    2013-11-01

    Planar microfluidic platforms for vector chromatography, in which different species fan out in different directions and can be continuously sorted, are particularly promising for the high throughput separation of multicomponent mixtures. We carry out a computational study of the vector separation of dilute suspensions of rigid and flexible particles transported by a pressure-driven flow over an array of slanted open cavities. The numerical scheme is based on a Stokes flow boundary integral equation method. The simulations are performed in a periodic system without lateral confinement, relevant to microfluidic devices with negligible recirculation in the main channel. We study the deflection of rigid spherical particles, of flexible capsules as a model of white and red blood cells, and of rigid discoidal particles as a model of platelets. We characterize the deflection of different particles as a function of their size, shape, shear elasticity, their release position, and the geometric parameters of the channel. The simulations provide insight into the separation mechanism and allow the optimization of specific devices depending on the application. Good agreement with experiments is observed.

  16. Recording sensory and motor information from peripheral nerves with Utah Slanted Electrode Arrays.

    Science.gov (United States)

    Clark, Gregory A; Ledbetter, Noah M; Warren, David J; Harrison, Reid R

    2011-01-01

    Recording and stimulation via high-count penetrating microelectrode arrays implanted in peripheral nerves may help restore precise motor and sensory function after nervous system damage or disease. Although previous work has demonstrated safety and relatively successful stimulation for long-term implants of 100-electrode Utah Slanted Electrode Arrays (USEAs) in feline sciatic nerve [1], two major remaining challenges were 1) to maintain viable recordings of nerve action potentials long-term, and 2) to overcome contamination of unit recordings by myoelectric (EMG) activity in awake, moving animals. In conjunction with improvements to USEAs themselves, we have redesigned several aspects of our USEA containment and connector systems. Although further increases in unit yield and long-term stability remain desirable, here we report considerable progress toward meeting both of these goals: We have successfully recorded unit activity from USEAs implanted intrafascicularly in sciatic nerve for periods up to 4 months (the terminal experimental time point), and we have developed a containment system that effectively eliminates or substantially reduces EMG contamination of unit recordings in the moving animal. In addition, we used a 100-channel wireless recording integrated circuit attached to implanted USEAs to transmit broadband or spike-threshold data from nerve. Neural data thusly obtained during imposed limb movements were decoded blindly to drive a virtual prosthetic limb in real time. These results support the possibility of using USEAs in peripheral nerves to provide motor control and cutaneous or proprioceptive sensory feedback in individuals after limb loss or spinal cord injury.

  17. Generating an image of dispersive energy by frequency decomposition and slant stacking

    Science.gov (United States)

    Xia, J.; Xu, Y.; Miller, R.D.

    2007-01-01

    We present a new algorithm for calculating an image of dispersive energy in the frequency-velocity (f-v) domain. The frequency decomposition is first applied to a shot gather in the offset-time domain to stretch impulsive data into pseudo-vibroseis data or frequency-swept data. Because there is a deterministic relationship between frequency and time in a sweep used in the frequency decomposition, the first step theoretically completes the transform from time to frequency. The slant stacking is then performed on the frequency-swept data to complete the transform from offset to velocity. This simple two-step algorithm generates an image of dispersive energy in the f-v domain. The straightforward transform only uses offset information of data so that this algorithm can be applied to data acquired with arbitrary geophone-acquisition geometry. Examples of synthetic and real-world data demonstrate that this algorithm generates accurate images of dispersive energy of the fundamental as well as higher modes. ?? Birkha??user Verlag, Basel, 2007.

  18. Slant hole completion test (1991) sidetrack as built'' report

    Energy Technology Data Exchange (ETDEWEB)

    Myal, F.R.

    1992-05-01

    During the summer of 1990, a slant hole test well, funded by the US Department of Energy, was drilled to 9,466 ft to evaluate the effectiveness of directional drilling in the tight, naturally fractured gas sands and coals of the Mesaverde Group. The surface location of the SHCT No. 1 is 700 ft south of the DOE Multiwell Experiment (MWX) site in Section 34, T6S, R94W, Garfield County, Colorado, approximately 7.5 miles west of Rifle. Mechanical problems following cementing of a production liner resulted in loss of the completion interval, and operations were suspended. In early 1991, DOE decided to sidetrack the hole to permit production testing of the lost interval. The sidetrack was designed to parallel the original wellbore, but to be drilled 1,000 ft to the east to minimize the chances of encountering formation damage from the original hole. The sidetrack, like the original hole, was to intersect the paludal lenticular sands and coals at 60{degrees} and to penetrate the underlying Cozzette sand horizonally. The sidetrack was spudded May 12, 1991. After re-entering the well in late 1991, early production testing of the Cozzette showed that the 300 ft of in-pay horizontal hole can produce at rate 5 to 10 times higher than vertical wells in the same area. This report contains the geological summary and sidetrack drilling operations summary.

  19. Wormholes immersed in rotating matter

    Directory of Open Access Journals (Sweden)

    Christian Hoffmann

    2018-03-01

    Full Text Available We demonstrate that rotating matter sets the throat of an Ellis wormhole into rotation, allowing for wormholes which possess full reflection symmetry with respect to the two asymptotically flat spacetime regions. We analyze the properties of this new type of rotating wormholes and show that the wormhole geometry can change from a single throat to a double throat configuration. We further discuss the ergoregions and the lightring structure of these wormholes.

  20. Wormholes immersed in rotating matter

    Science.gov (United States)

    Hoffmann, Christian; Ioannidou, Theodora; Kahlen, Sarah; Kleihaus, Burkhard; Kunz, Jutta

    2018-03-01

    We demonstrate that rotating matter sets the throat of an Ellis wormhole into rotation, allowing for wormholes which possess full reflection symmetry with respect to the two asymptotically flat spacetime regions. We analyze the properties of this new type of rotating wormholes and show that the wormhole geometry can change from a single throat to a double throat configuration. We further discuss the ergoregions and the lightring structure of these wormholes.

  1. Wormholes immersed in rotating matter

    OpenAIRE

    Hoffmann, Christian; Ioannidou, Theodora; Kahlen, Sarah; Kleihaus, Burkhard; Kunz, Jutta

    2018-01-01

    We demonstrate that rotating matter sets the throat of an Ellis wormhole into rotation, allowing for wormholes which possess full reflection symmetry with respect to the two asymptotically flat spacetime regions. We analyze the properties of this new type of rotating wormholes and show that the wormhole geometry can change from a single throat to a double throat configuration. We further discuss the ergoregions and the lightring structure of these wormholes.

  2. Bidirectional optical rotation of cells

    Science.gov (United States)

    Wu, Jiyi; Zhang, Weina; Li, Juan

    2017-08-01

    Precise and controlled rotation manipulation of cells is extremely important in biological applications and biomedical studies. Particularly, bidirectional rotation manipulation of a single or multiple cells is a challenge for cell tomography and analysis. In this paper, we report an optical method that is capable of bidirectional rotation manipulation of a single or multiple cells. By launching a laser beam at 980 nm into dual-beam tapered fibers, a single or multiple cells in solutions can be trapped and rotated bidirectionally under the action of optical forces. Moreover, the rotational behavior can be controlled by altering the relative distance between the two fibers and the input optical power. Experimental results were interpreted by numerical simulations.

  3. Bidirectional optical rotation of cells

    Directory of Open Access Journals (Sweden)

    Jiyi Wu

    2017-08-01

    Full Text Available Precise and controlled rotation manipulation of cells is extremely important in biological applications and biomedical studies. Particularly, bidirectional rotation manipulation of a single or multiple cells is a challenge for cell tomography and analysis. In this paper, we report an optical method that is capable of bidirectional rotation manipulation of a single or multiple cells. By launching a laser beam at 980 nm into dual-beam tapered fibers, a single or multiple cells in solutions can be trapped and rotated bidirectionally under the action of optical forces. Moreover, the rotational behavior can be controlled by altering the relative distance between the two fibers and the input optical power. Experimental results were interpreted by numerical simulations.

  4. Physics conditions for robust control of tearing modes in a rotating tokamak plasma

    Science.gov (United States)

    Lazzaro, E.; Borgogno, D.; Brunetti, D.; Comisso, L.; Fevrier, O.; Grasso, D.; Lutjens, H.; Maget, P.; Nowak, S.; Sauter, O.; Sozzi, C.; the EUROfusion MST1 Team

    2018-01-01

    The disruptive collapse of the current sustained equilibrium of a tokamak is perhaps the single most serious obstacle on the path toward controlled thermonuclear fusion. The current disruption is generally too fast to be identified early enough and tamed efficiently, and may be associated with a variety of initial perturbing events. However, a common feature of all disruptive events is that they proceed through the onset of magnetohydrodynamic instabilities and field reconnection processes developing magnetic islands, which eventually destroy the magnetic configuration. Therefore the avoidance and control of magnetic reconnection instabilities is of foremost importance and great attention is focused on the promising stabilization techniques based on localized rf power absorption and current drive. Here a short review is proposed of the key aspects of high power rf control schemes (specifically electron cyclotron heating and current drive) for tearing modes, considering also some effects of plasma rotation. From first principles physics considerations, new conditions are presented and discussed to achieve control of the tearing perturbations by means of high power ({P}{{EC}}≥slant {P}{{ohm}}) in regimes where strong nonlinear instabilities may be driven, such as secondary island structures, which can blur the detection and limit the control of the instabilities. Here we consider recent work that has motivated the search for the improvement of some traditional control strategies, namely the feedback schemes based on strict phase tracking of the propagating magnetic islands.

  5. On steady rotations of a rigid body bearing a single-axis powered gyroscope whose precession axis is parallel to a principal plane of inertia

    NARCIS (Netherlands)

    Amel'kin, N. I.

    The set of steady motions of the system named in the title is represented parametrically via the gyro gimbal rotation angle for an arbitrary position of the gimbal axis. We study the set of steady motions for a system in which the gyro gimbal axis is parallel to a principal plane of inertia as well

  6. Rotating preventers

    International Nuclear Information System (INIS)

    Tangedahl, M.J.; Stone, C.R.

    1992-01-01

    This paper reports that recent changes in the oil and gas industry and ongoing developments in horizontal and underbalanced drilling necessitated development of a better rotating head. A new device called the rotating blowout preventer (RBOP) was developed by Seal-Tech. It is designed to replace the conventional rotating control head on top of BOP stacks and allows drilling operations to continue even on live (underbalanced) wells. Its low wear characteristics and high working pressure (1,500 psi) allow drilling rig crews to drill safely in slightly underbalanced conditions or handle severe well control problems during the time required to actuate other BOPs in the stack. Drilling with a RBOP allows wellbores to be completely closed in tat the drill floor rather than open as with conventional BOPs

  7. Vibrations of rotating machinery

    CERN Document Server

    Matsushita, Osami; Kanki, Hiroshi; Kobayashi, Masao; Keogh, Patrick

    2017-01-01

    This book opens with an explanation of the vibrations of a single degree-of-freedom (dof) system for all beginners. Subsequently, vibration analysis of multi-dof systems is explained by modal analysis. Mode synthesis modeling is then introduced for system reduction, which aids understanding in a simplified manner of how complicated rotors behave. Rotor balancing techniques are offered for rigid and flexible rotors through several examples. Consideration of gyroscopic influences on the rotordynamics is then provided and vibration evaluation of a rotor-bearing system is emphasized in terms of forward and backward whirl rotor motions through eigenvalue (natural frequency and damping ratio) analysis. In addition to these rotordynamics concerning rotating shaft vibration measured in a stationary reference frame, blade vibrations are analyzed with Coriolis forces expressed in a rotating reference frame. Other phenomena that may be assessed in stationary and rotating reference frames include stability characteristic...

  8. Study on the annular leakage-flow-induced vibrations. 1st Report. Stability for translational and rotational single-degree-of-freedom systems; Kanjo sukimaryu reiki shindo ni kansuru kenkyu. 1. Heishin oyobi kaiten 1 jiyudokei no anteise

    Energy Technology Data Exchange (ETDEWEB)

    Li, D.W. [Hitachi, Ltd., Tokyo (Japan); Kaneko, S. [The University of Tokyo, Tokyo (Japan); Hayama, S. [Toyama Prefectural University, Toyama (Japan)

    1999-07-25

    This study reports the stability of annular leakage-flow-induced vibrations. The pressure distribution of fluid between a fixed outer cylinder and a vibrating inner cylinder was obtained in the case of a translationally and rotationally coupled motion of the inner cylinder. The unsteady fluid force acting on the inner cylinder in the case of translational and rotational single-degree-of-freedom vibrations was then expressed in terms proportional to the acceleration, velocity, and displacement. Then the critical flow rate (at which stability was lost) was determined for an annular leakage-flow-induced vibration. Finally, the stability was investigated theoretically. It is known that instability will occur in the case of a divergent passage, but the critical flow rate depends on the passage increment in a limited range: the eccentricity of the passage and the pressure loss factor at the inlet of the passage lower the stability. (author)

  9. Interaction of z component of magnetic field between two samples of GO material in the round rotational single sheet tester (RRSST)

    International Nuclear Information System (INIS)

    Gorican, Viktor; Hamler, Anton; Jesenik, Marko; Stumberger, Bojan; Trlep, Mladen

    2006-01-01

    The magnetic properties of two grain-oriented (GO) samples of the same grade were measured under alternating and rotational magnetic flux conditions. Two samples were measured separately and then together in different arrangement to each other. The interaction of magnetic field between two samples were measured by using a coil, which was placed in between. The results show that the H z component influence measured magnetic properties in the x-y plane

  10. Slanted annular aperture arrays as enhanced-transmission metamaterials: Excitation of the plasmonic transverse electromagnetic guided mode

    Energy Technology Data Exchange (ETDEWEB)

    Ndao, Abdoulaye; Salut, Roland; Baida, Fadi I., E-mail: fbaida@univ-fcomte.fr [Département d' Optique P.M. Duffieux, Institut FEMTO-ST, UMR 6174 CNRS, Université de Franche–Comté, 25030 Besançon Cedex (France); Belkhir, Abderrahmane [Laboratoire de Physique et Chimie Quantique, Université Mouloud Mammeri, Tizi-Ouzou (Algeria)

    2013-11-18

    We present here the fabrication and the optical characterization of slanted annular aperture arrays engraved into silver film. An experimental enhanced transmission based on the excitation of the cutoff-less plasmonic guided mode of the nano-waveguides (the transmission electron microscopy mode) is demonstrated and agrees well with the theoretical predicted results. By the way, even if it is less efficient (70% → 20%), an enhanced transmission can occur at larger wavelength value (720 nm–930 nm) compared to conventional annular aperture arrays structure by correctly setting the metal thickness.

  11. An SVM-Based Classifier for Estimating the State of Various Rotating Components in Agro-Industrial Machinery with a Vibration Signal Acquired from a Single Point on the Machine Chassis

    Directory of Open Access Journals (Sweden)

    Ruben Ruiz-Gonzalez

    2014-11-01

    Full Text Available The goal of this article is to assess the feasibility of estimating the state of various rotating components in agro-industrial machinery by employing just one vibration signal acquired from a single point on the machine chassis. To do so, a Support Vector Machine (SVM-based system is employed. Experimental tests evaluated this system by acquiring vibration data from a single point of an agricultural harvester, while varying several of its working conditions. The whole process included two major steps. Initially, the vibration data were preprocessed through twelve feature extraction algorithms, after which the Exhaustive Search method selected the most suitable features. Secondly, the SVM-based system accuracy was evaluated by using Leave-One-Out cross-validation, with the selected features as the input data. The results of this study provide evidence that (i accurate estimation of the status of various rotating components in agro-industrial machinery is possible by processing the vibration signal acquired from a single point on the machine structure; (ii the vibration signal can be acquired with a uniaxial accelerometer, the orientation of which does not significantly affect the classification accuracy; and, (iii when using an SVM classifier, an 85% mean cross-validation accuracy can be reached, which only requires a maximum of seven features as its input, and no significant improvements are noted between the use of either nonlinear or linear kernels.

  12. Optical illusions induced by rotating medium

    Science.gov (United States)

    Zang, XiaoFei; Huang, PengCheng; Zhu, YiMing

    2018-03-01

    Different from the traditional single-function electromagnetic wave rotators (rotate the electromagnetic wavefronts), we propose that rotating medium can be extended to optical illusions such as breaking the diffraction limit and overlapping illusion. Furthermore, the homogeneous but anisotropic rotating medium is simplified by homogeneous and isotropic positive-index materials according to the effective medium theory, which is helpful for future device fabrication. Finite element simulations for the two-dimensional case are performed to demonstrate these properties.

  13. Muon spin rotation study of magnetism and superconductivity in Ba(Fe1-xCox)2As2 single crystals

    OpenAIRE

    Bernhard, C.; Wang, C. N.; Nuccio, L.; Schulz, L.; Zaharko, O.; Larsen, Jacob; Aristizabal, C.; Willis, M.; Drew, A. J.; Varma, G. D.; Wolf, T.; Niedermayer, Ch.

    2012-01-01

    Using muon spin rotation (μSR) we investigated the magnetic and superconducting properties of a series of Ba(Fe1−xCox)2As2 single crystals with 0 ≤x ≤0.15. Our study details how the antiferromagnetic order is suppressed upon Co substitution and how it coexists with superconductivity. In the nonsuperconducting samples at 0

  14. A Design of Wide Band and Wide Beam Cavity-Backed Slot Antenna Array with Slant Polarization

    Directory of Open Access Journals (Sweden)

    Huiying Qi

    2016-01-01

    Full Text Available Design of antenna array under the limitation of restricted size is a challenging problem. Cavity-backed slot antenna is widely used because of its advantages of small size, wide band, and wide beam. In this paper, a design of wide band and wide beam cavity-backed slot antenna array with the slant polarization is proposed. To obtain wide band and wide beam with limited size, the inverted microstrip-fed cavity-backed slot antenna (IMF-CBSA is adopted as the element of 1 × 4 antenna array. The slant polarized antennas and their feeding networks are adopted because of their simple structures. The performance of the proposed antenna array is verified by the simulations and experiments. The measured VSWR < 2 bandwidth is 55% at the center frequency 21.8 GHz, and the gain is larger than 12.2 dB. Experimental results demonstrate that the proposed design achieves wide band and beam with the size of 68 mm × 56 mm × 14.5 mm.

  15. Measurement of the modulation transfer function of a charge-coupled device array by the combination of the self-imaging effect and slanted edge method.

    Science.gov (United States)

    Najafi, Sedigheh; Madanipour, Khosro

    2013-07-01

    In this paper, by a combination of the self-imaging effect for Ronchi gratings and the standard slanted edge modulation transfer function (MTF) measurement method for CCD cameras, the MTF of the CCD array without optics is measured. For this purpose, a Ronchi-type grating is illuminated by an expanded He-Ne laser. A self-image of the grating appears without optics on the CCD array that is located on the Talbot distance. The lines of the self-image of the grating are used as a slanted edge array. This method has all the advantages of the slanted edge method, and also since the array of the edge is ready, the total area of the CCD can be tested. The measured MTF is related to the CCD array without optics.

  16. A C/X Dual-band Wide-angle Reflective Polarization Rotation Metasurface

    Directory of Open Access Journals (Sweden)

    Y. Zhou

    2017-09-01

    Full Text Available In this paper, a C/X dual-band wide-angle re¬flective polarization rotation metasurface (PRMS with high rotation efficiency is proposed and realized. Aiming to miniaturize the size of the unit cell, a metallic flower-like shape ring is selected to extend the current path and the 45 degree slanting stitch along diagonal direction is used to form the asymmetric structure. The simulated results show that the proposed PRMS achieves polarization rotation at 4.61 GHz and 8.67 GHz with high efficiency, at which the linear polarization incident wave is converted into its orthogonal polarization after reflection. Furthermore, the high polarization rotation efficiency of the proposed PRMS is maintained under an oblique incident direction from 0° to 60°. To verify the simulated results, the proposed PRMS is fabricated and measured. The measured results are in good accordance with the simulated ones.

  17. In flight measurement of steady and unsteady blade surface pressure of a single rotation large scale advanced prop-fan installed on the PTA aircraft

    Science.gov (United States)

    Parzych, D.; Boyd, L.; Meissner, W.; Wyrostek, A.

    1991-01-01

    An experiment was performed by Hamilton Standard, Division of United Technologies Corporation, under contract by LeRC, to measure the blade surface pressure of a large scale, 8 blade model prop-fan in flight. The test bed was the Gulfstream 2 Prop-Fan Test Assessment (PTA) aircraft. The objective of the test was to measure the steady and periodic blade surface pressure resulting from three different Prop-Fan air inflow angles at various takeoff and cruise conditions. The inflow angles were obtained by varying the nacelle tilt angles, which ranged from -3 to +2 degrees. A range of power loadings, tip speeds, and altitudes were tested at each nacelle tilt angle over the flight Mach number range of 0.30 to 0.80. Unsteady blade pressure data tabulated as Fourier coefficients for the first 35 harmonics of shaft rotational frequency and the steady (non-varying) pressure component are presented.

  18. Utilization of O4 slant column density to derive aerosol layer height from a space-borne UV–visible hyperspectral sensor: sensitivity and case study

    Directory of Open Access Journals (Sweden)

    S. S. Park

    2016-02-01

    Full Text Available The sensitivities of oxygen-dimer (O4 slant column densities (SCDs to changes in aerosol layer height are investigated using the simulated radiances by a radiative transfer model, the linearized pseudo-spherical vector discrete ordinate radiative transfer (VLIDORT, and the differential optical absorption spectroscopy (DOAS technique. The sensitivities of the O4 index (O4I, which is defined as dividing O4 SCD by 1040 molecules2 cm−5, to aerosol types and optical properties are also evaluated and compared. Among the O4 absorption bands at 340, 360, 380, and 477 nm, the O4 absorption band at 477 nm is found to be the most suitable to retrieve the aerosol effective height. However, the O4I at 477 nm is significantly influenced not only by the aerosol layer effective height but also by aerosol vertical profiles, optical properties including single scattering albedo (SSA, aerosol optical depth (AOD, particle size, and surface albedo. Overall, the error of the retrieved aerosol effective height is estimated to be 1276, 846, and 739 m for dust, non-absorbing, and absorbing aerosol, respectively, assuming knowledge on the aerosol vertical distribution shape. Using radiance data from the Ozone Monitoring Instrument (OMI, a new algorithm is developed to derive the aerosol effective height over East Asia after the determination of the aerosol type and AOD from the MODerate resolution Imaging Spectroradiometer (MODIS. About 80 % of retrieved aerosol effective heights are within the error range of 1 km compared to those obtained from the Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP measurements on thick aerosol layer cases.

  19. Utilization of O4 Slant Column Density to Derive Aerosol Layer Height from a Space-Borne UV-Visible Hyperspectral Sensor: Sensitivity and Case Study

    Science.gov (United States)

    Park, Sang Seo; Kim, Jhoon; Lee, Hanlim; Torres, Omar; Lee, Kwang-Mog; Lee, Sang Deok

    2016-01-01

    The sensitivities of oxygen-dimer (O4) slant column densities (SCDs) to changes in aerosol layer height are investigated using the simulated radiances by a radiative transfer model, the linearized pseudo-spherical vector discrete ordinate radiative transfer (VLIDORT), and the differential optical absorption spectroscopy (DOAS) technique. The sensitivities of the O4 index (O4I), which is defined as dividing O4 SCD by 10(sup 40) molecules (sup 2) per centimeters(sup -5), to aerosol types and optical properties are also evaluated and compared. Among the O4 absorption bands at 340, 360, 380, and 477 nanometers, the O4 absorption band at 477 nanometers is found to be the most suitable to retrieve the aerosol effective height. However, the O4I at 477 nanometers is significantly influenced not only by the aerosol layer effective height but also by aerosol vertical profiles, optical properties including single scattering albedo (SSA), aerosol optical depth (AOD), particle size, and surface albedo. Overall, the error of the retrieved aerosol effective height is estimated to be 1276, 846, and 739 meters for dust, non-absorbing, and absorbing aerosol, respectively, assuming knowledge on the aerosol vertical distribution shape. Using radiance data from the Ozone Monitoring Instrument (OMI), a new algorithm is developed to derive the aerosol effective height over East Asia after the determination of the aerosol type and AOD from the MODerate resolution Imaging Spectroradiometer (MODIS). About 80 percent of retrieved aerosol effective heights are within the error range of 1 kilometer compared to those obtained from the Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) measurements on thick aerosol layer cases.

  20. Utilization of O4 Slant Column Density to Derive Aerosol Layer Height from a Spaceborne UV-Visible Hyperspectral Sensor: Sensitivity and Case Study

    Science.gov (United States)

    Park, Sang Seo; Kim, Jhoon; Lee, Hanlim; Torres, Omar; Lee, Kwang-Mog; Lee, Sang Deok

    2016-01-01

    The sensitivities of oxygen-dimer (O4) slant column densities (SCDs) to changes in aerosol layer height are investigated using the simulated radiances by a radiative transfer model, the linearized pseudo-spherical vector discrete ordinate radiative transfer (VLIDORT), and the Differential Optical Absorption Spectroscopy (DOAS) technique. The sensitivities of the O4 index (O4I), which is defined as dividing O4 SCD by 10(exp 40) sq molecules cm(exp -5), to aerosol types and optical properties are also evaluated and compared. Among the O4 absorption bands at 340, 360, 380, and 477 nm, the O4 absorption band at 477 nm is found to be the most suitable to retrieve the aerosol effective height. However, the O4I at 477 nm is significantly influenced not only by the aerosol layer effective height but also by aerosol vertical profiles, optical properties including single scattering albedo (SSA), aerosol optical depth (AOD), particle size, and surface albedo. Overall, the error of the retrieved aerosol effective height is estimated to be 1276, 846, and 739 m for dust, non-absorbing, and absorbing aerosol, respectively, assuming knowledge on the aerosol vertical distribution shape. Using radiance data from the Ozone Monitoring Instrument (OMI), a new algorithm is developed to derive the aerosol effective height over East Asia after the determination of the aerosol type and AOD from the MODerate resolution Imaging Spectroradiometer (MODIS). About 80% of retrieved aerosol effective heights are within the error range of 1 km compared to those obtained from the Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) measurements on thick aerosol layer cases.

  1. Rotational scanography

    International Nuclear Information System (INIS)

    Moore, R.; Amplatz, K.

    1981-01-01

    With rotational scanography contrast and resolution of X-ray images are improved. The technique bases on the principle of a narrow X-ray passing along an object, thus exposing the whole film. The X-ray is limited by a primary shield next to the X-ray tube. A second shield between object and film prevents that scattered rays spoil the film. The X-ray tube is turned around a horizontal axis, whilst the shield is shifted so that the irradiation intensity remains constant and the smallest projected focal size is obtained. This technique permits to enlarge the X-ray images by 3 or 6 times its size. Thus, films up to a length of 96 cm can be exposed. Main advantages of rotary scanography are reduced exposure to radiation of patient and applicant, improved contrast and resolution of the X-ray image, and a larger play of exposure for the X-ray technique. Disadvantages are a longer exposure time and the consequently increased demands on X-ray generator and treatment head. When a multi-slit shield is used, the patient must be cooperative in order to prevent movement artifacts. This imaging technique is highly sensitive to artifacts, particularly if the tube voltage provides large fluctuations. Supplementary units are necessary. The significance of the rotational scanography is that it permits the reduction of the radiation dose, whilst contrast and resolution of the images are improved. This can be illustrated by X-ray images of a CT-phantom and of pelvic, hand and gastrointenstinal phantoms. (orig./MG) [de

  2. Performance analysis of a novel planetary speed increaser used in single-rotor wind turbines with counter-rotating electric generator

    Science.gov (United States)

    Saulescu, R.; Neagoe, M.; Munteanu, O.; Cretescu, N.

    2016-08-01

    The paper presents a study on the kinematic and static performances of a new type of 1DOF (Degree Of Freedom) planetary speed increaser to be implemented in wind turbines, a transmission with three operating cases: a) one input and one output, b) one input and two outputs, in which the speed of the secondary output is equal to the input speed, and c) with one input and two outputs, where the secondary output speed is higher than the input speed. The proposed speed increaser contains two sun gears and a double satellite, allowing operation with an output connected to the fixed stator of a classic generator (case I) or with two counterrotating outputs that drive a counter-rotating generator (with a mobile stator). A new variant of planetary transmission capable of providing the speed increase of the generator stator and, thus, the increase of the relative speed between the generator rotor and stator is obtained by the parallel connection of the speed increaser with a planetary gear. The three conceptual variants of planetary transmission are analytically modelled and comparatively analysed based on a set of kinematic and static parameters. The proposed transmission has higher performances compared to the same transmission with one input and one output, the increase of the kinematic amplification ratio and efficiency being achieved simultaneously.

  3. Attenuation-corrected radionuclide differential glomerular filtration: Using a bilateral slant hole collimator for determining depth of kidneys

    International Nuclear Information System (INIS)

    Lasher, J.C.; Kopp, D.T.; Lancaster, J.L.; Blumhardt, R.

    1986-01-01

    There has recently been considerable interest in measuring differential renal function utilizing radionuclide attenuation correction techniques. One popular method is that of estimating kidney depth from the patient's weight-to-height ratio. A recent publication showed that renal depth can also be accurately determined using measurements from lateral views of each kidney. The authors have developed a third radionculide method using a bilateral slant-hole collimator (SHC) that is capable of obtaining the depth of both kidneys without repositioning the camera. This method makes use of the fact that two unique projections of each kidney are simultaneously acquired along spatial angles. The depth of each kidney used in the attenuation correction calculation can be easily obtained trigometrically using this known angle and the distance of the collimator from the patient

  4. Intensity and average orbital angular momentum of partially coherent flat-topped vortex beam in slant atmospheric turbulence

    Science.gov (United States)

    Li, Ya-qing; Wang, Li-guo

    2017-11-01

    On the basis of the extended Huygens-Fresnel principle and the cross-spectral density function (CSDF), the intensity and average orbital angular momentum (OAM) of the partially coherent flat-topped vortex beams in the slant atmospheric turbulence are presented. The effects of the order, topological charge, waist radius, and propagation distance of the beam on the intensity and average OAM are discussed. Results obtained show that the intensity of the partially coherent flat-topped vortex beam is changed due to the variations of the propagation distance, waist radius, topological charge and beam order, the average OAM is constant during the beam propagation in the atmospheric turbulence and related only to the waist radius and beam order. Results obtained by this paper may serve as theory bases for future applications in the atmospheric optical communication.

  5. Comparison of slant-path scintillometry, sonic anemometry and high-speed videography for vertical profiling of turbulence in the atmospheric surface layer

    CSIR Research Space (South Africa)

    Griffith, DJ

    2013-09-01

    Full Text Available of techniques as well as to obtain representative turbulence profile data for temperate grassland. A key element of the experimental layout is to place a sonic anemometer 15 m above ground at the centre of a 1 km slant-path extending from ground level to a...

  6. Effect of home-based training using a slant board with dorsiflexed ankles on walking function in post-stroke hemiparetic patients.

    Science.gov (United States)

    Nakayama, Yasuhide; Iijima, Setsu; Kakuda, Wataru; Abo, Masahiro

    2016-08-01

    [Purpose] To investigate the effects of a 30-day rehabilitation program using a slant board on walking function in post-stroke hemiparetic patients. [Subjects and Methods] Six hemiparetic patients with gait disturbance were studied. The patients were instructed to perform a home-based rehabilitation program using a slant board, thrice daily for 30 days, the exercise included standing on the slant board for 3 minutes, with both ankles dorsiflexed without backrest. For all patients, the Brunnstrom Recovery Stage, Barthel Index, range of motion of the ankle joint, modified Ashworth scale scole for calf muscle, sensory impairments with Numeral Rating Scale, maximum walking speed, number of steps, and Timed "Up and Go" test were serially evaluated at the beginning and end of the 30-day program. [Results] The program significantly increased walking velocity, decreased the number of steps in the 10-m walking test, and decreased Timed "Up and Go" test performance time. [Conclusion] This rehabilitation program using the slant board was safe and improved walking function in patients. The improvement in walking function could be due to a forward shift of the center of gravity, which can be an important part of motor learning for gait improvement.

  7. Measurement of the steady surface pressure distribution on a single rotation large scale advanced prop-fan blade at Mach numbers from 0.03 to 0.78

    Science.gov (United States)

    Bushnell, Peter

    1988-01-01

    The aerodynamic pressure distribution was determined on a rotating Prop-Fan blade at the S1-MA wind tunnel facility operated by the Office National D'Etudes et de Recherches Aerospatiale (ONERA) in Modane, France. The pressure distributions were measured at thirteen radial stations on a single rotation Large Scale Advanced Prop-Fan (LAP/SR7) blade, for a sequence of operating conditions including inflow Mach numbers ranging from 0.03 to 0.78. Pressure distributions for more than one power coefficient and/or advanced ratio setting were measured for most of the inflow Mach numbers investigated. Due to facility power limitations the Prop-Fan test installation was a two bladed version of the eight design configuration. The power coefficient range investigated was therefore selected to cover typical power loading per blade conditions which occur within the Prop-Fan operating envelope. The experimental results provide an extensive source of information on the aerodynamic behavior of the swept Prop-Fan blade, including details which were elusive to current computational models and do not appear in the two-dimensional airfoil data.

  8. All-solid-state thin film battery based on well-aligned slanted LiCoO{sub 2} nanowires fabricated by glancing angle deposition

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Miyoung [Department of Materials Science and Engineering, Yonsei University, Seoul 120-749 (Korea, Republic of); Lee, Seunghwan [High Temperature Energy Materials Research Center, Korea Institute of Science and Technology, Seoul 136-791 (Korea, Republic of); Department of Energy Science, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Lee, Daehee [Department of Materials Science and Engineering, Yonsei University, Seoul 120-749 (Korea, Republic of); Kim, Joosun, E-mail: joosun@kist.re.kr [High Temperature Energy Materials Research Center, Korea Institute of Science and Technology, Seoul 136-791 (Korea, Republic of); Moon, Jooho, E-mail: jmoon@yonsei.ac.kr [Department of Materials Science and Engineering, Yonsei University, Seoul 120-749 (Korea, Republic of)

    2017-08-01

    Graphical abstract: We successfully fabricated well-aligned slanted LiCoO{sub 2} nanowires as a one-dimensional nanostructured cathode by glancing angle deposition to enhance the electrochemical performance of all-solid-state thin film batteries. - Highlights: • Well-aligned slanted LiCoO{sub 2} nanowires are fabricated by glancing angle deposition. • One-dimensional nanostructured LiCoO{sub 2} cathode enlarges the contact area. • All-solid-state thin film battery exhibits enhances rate capability and cycling stability. - Abstract: We fabricated all-solid-state thin film batteries based on well-aligned slanted LiCoO{sub 2} nanowires by glancing angle deposition, as a facile template-free method in order to increase the electrochemically active site, i.e., the contact area between the solid electrolyte and the electrode. A highly porous thin film composed of well-separated slanted LiCoO{sub 2} nanowires not only facilitates the penetration of solid electrolyte phase into the cathode, but also alleviates the thermally and mechanically induced stresses during post-annealing and electrochemical cycling. The all-solid-state thin film battery based on the well-aligned slanted LiCoO{sub 2} nanowires, whose contact area between electrolyte and electrode was three times as high as that of a dense thin film, could provide additional migration pathways for lithium ion diffusion due to the enlarged reaction sites. This resulted in enhanced electrochemical kinetics, thereby leading to better rate capability and long-term cyclic stability as compared to the dense LiCoO{sub 2} thin film.

  9. Rotating Cavitation Supression Project

    Data.gov (United States)

    National Aeronautics and Space Administration — FTT proposes development of a rotating cavitation (RC) suppressor for liquid rocket engine turbopump inducers. Cavitation instabilities, such as rotating cavitation,...

  10. Quantification of early fatty infiltration of the rotator cuff muscles: comparison of multi-echo Dixon with single-voxel MR spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Agten, Christoph A.; Rosskopf, Andrea B.; Pfirrmann, Christian W.A. [Balgrist University Hospital, Radiology, Zurich (Switzerland); University of Zurich, Faculty of Medicine, Zurich (Switzerland); Gerber, Christian [Balgrist University Hospital, Orthopaedic Surgery, Zurich (Switzerland); University of Zurich, Faculty of Medicine, Zurich (Switzerland)

    2016-10-15

    To evaluate quantification of early fatty infiltration in supraspinatus muscles with magnetic resonance (MR) imaging using a T2*-corrected multi-echo 3D-gradient-echo Dixon-based sequence (multi-echo Dixon) and compare it to proton-MR-spectroscopy. Sixty subjects (mean age 46 years, 41 men) with good supraspinatus muscle quality on 1.5 T MR imaging were included. Fat percentage (FP) in the supraspinatus muscle was quantified using a multi-echo Dixon compared to single-voxel MR spectroscopy as reference standard. In 18 subjects the multi-echo Dixon was repeated to assess test-retest reliability. Measurements based on multi-echo Dixon were performed by two independent readers by placing regions-of-interest (ROIs) in the supraspinatus muscle corresponding to the MR-spectroscopy voxel. Intraclass and concordance correlation coefficients (ICC/CCC) were used for statistical analysis. Test-retest reliability was substantial for reader 1 (ICC = 0.757) and almost perfect for reader 2 (ICC = 0.873). Inter-reader reliability for multi-echo Dixon was almost perfect (ICC = 0.893, P <.0005). Mean FP in all 60 subjects with multi-echo Dixon was 3.5 ± 1.6 for reader 1, 3.7 ± 1.8 for reader 2, and 2.8 ± 1.4 with MR spectroscopy. Correlation between multi-echo Dixon and MR spectroscopy was moderate (CCC = 0.641). The multi-echo Dixon sequence is a reliable method and comparable to MR-spectroscopy for quantification of low levels of fatty infiltration in the supraspinatus muscle. (orig.)

  11. Scintillation of partially coherent Gaussian—Schell model beam propagation in slant atmospheric turbulence considering inner- and outer-scale effects

    International Nuclear Information System (INIS)

    Li Ya-Qing; Wu Zhen-Sen; Zhang Yuan-Yuan; Wang Ming-Jun

    2014-01-01

    Based on the modified Rytov theory and the international telecommunication union-radio (ITU-R) slant atmospheric structure constant model, the uniform scintillation index of partially coherent Gaussian—Schell model (GSM) beam propagation in the slant path is derived from weak- to strong-turbulence regions considering inner- and outer-scale effects. The effects of wavelength of beams and inner- and outer-scale of turbulence on scintillation are analyzed numerically. Comparison between the scintillation of GSM beams under the von Karman spectrum and that of beams under the modified Hill spectrum is made. The results obtained show that the scintillation index obtained under the von Karman spectrum is smaller than that under the modified Hill spectrum. This study can find theory bases for the experiments of the partially coherent GSM beam propagation through atmospheric turbulence. (electromagnetism, optics, acoustics, heat transfer, classical mechanics, and fluid dynamics)

  12. Performance of GPS slant total electron content and IRI-Plas-STEC for days with ionospheric disturbance

    Directory of Open Access Journals (Sweden)

    Feza Arikan

    2016-01-01

    Full Text Available Total Electron Content (TEC is an important observable parameter of the ionosphere which forms the main source of error for space based navigation and positioning systems. Since the deployment of Global Navigation Satellite Systems (GNSS, cost-effective estimation of TEC between the earth based receiver and Global Positioning System (GPS satellites became the major means of investigation of local and regional disturbance for earthquake precursor and augmentation system studies. International Reference Ionosphere (IRI extended to plasmasphere (IRI-Plas is the most developed ionospheric and plasmaspheric climatic model that provides hourly, monthly median of electron density distribution globally. Recently, IONOLAB group (www.ionolab.org has presented a new online space weather service that can compute slant TEC (STEC on a desired ray path for a given date and time using IRI-Plas model (IRI-Plas-STEC. In this study, the performance of the model based STEC is compared with GPS-STEC computed according to the estimation method developed by the IONOLAB group and includes the receiver bias as IONOLAB-BIAS (IONOLAB-STEC. Using Symmetric Kullback–Leibler Distance (SKLD, Cross Correlation (CC coefficient and the metric norm (L2N to compare IRI-Plas-STEC and IONOLAB-STEC for the month of October 2011 over the Turkish National Permanent GPS Network (TNPGN-Active, it has been observed that SKLD provides a good indicator of disturbance for both earthquakes and geomagnetic storms.

  13. Theoretical description of the photopyroelectric technique in the slanted detector configuration for thermal diffusivity measurements in fluids

    Energy Technology Data Exchange (ETDEWEB)

    Rojas-Trigos, J.B., E-mail: rjosebruno@yahoo.com.mx [Instituto Politécnico Nacional, Centro de Investigación en Ciencia Aplicada y Tecnología Avanzada, Legaría 694, Colonia Irrigación, C.P. 11500 México D. F. (Mexico); Marín, E. [Instituto Politécnico Nacional, Centro de Investigación en Ciencia Aplicada y Tecnología Avanzada, Legaría 694, Colonia Irrigación, C.P. 11500 México D. F. (Mexico); Mansanares, A.M. [Instituto de Física Gleb Wataghin, Universidade Estadual de Campinas, UNICAMP, 13083-859 Campinas, SP (Brazil); Cedeño, E.; Juárez-Gracia, G.; Calderón, A. [Instituto Politécnico Nacional, Centro de Investigación en Ciencia Aplicada y Tecnología Avanzada, Legaría 694, Colonia Irrigación, C.P. 11500 México D. F. (Mexico)

    2014-04-01

    Highlights: • A model for photopyroelectric thermal characterization of fluids is presented. • A slanted detector configuration is considered with a finite measurement cell. • The mean temperature distribution in the photopyroelectric detector, as function of the beam spot position, is calculated. • The influence of the excitation beam spot size, the thermal diffusion length and size of the sample is discussed. • The high lateral resolution of the method observed in experiments is explain. - Abstract: This work presents an extended description about the theoretical aspects related to the generation of the photopyroelectric signal in a recently proposed wedge-like heat transmission detection configuration, which recreates the well-known Angstrom method (widely used for solid samples) for accurate thermal diffusivity measurement in gases and liquids. The presented model allows for the calculation of the temperature profile detected by the pyroelectric sensor as a function of the excitation beam position, and the study of the influence on it of several parameters, such as spot size, thermal properties of the absorber layer, and geometrical parameters of the measurement cell. Through computer simulations, it has been demonstrated that a narrow temperature distribution is created at the sensor surface, independently of the lateral diffusion of heat taking place at the sample's surface.

  14. On the coupled unsaturated–saturated flow process induced by vertical, horizontal, and slant wells in unconfined aquifers

    Directory of Open Access Journals (Sweden)

    X. Liang

    2017-03-01

    established with special consideration of the coupled unsaturated–saturated flow process and the well orientation. Groundwater flow in the saturated zone is described by a three-dimensional governing equation and a linearized three-dimensional Richards' equation in the unsaturated zone. A solution in the Laplace domain is derived by the Laplace–finite-Fourier-transform and the method of separation of variables, and the semi-analytical solutions are obtained using a numerical inverse Laplace method. The solution is verified by a finite-element numerical model. It is found that the effects of the unsaturated zone on the drawdown of a pumping test exist at any angle of inclination of the pumping well, and this impact is more significant in the case of a horizontal well. The effects of the unsaturated zone on the drawdown are independent of the length of the horizontal well screen. The vertical well leads to the largest water volume drained from the unsaturated zone (W during the early pumping time, and the effects of the well orientation on W values become insignificant at the later time. The screen length of the horizontal well does not affect W for the whole pumping period. The proposed solutions are useful for the parameter identification of pumping tests with a general well orientation (vertical, horizontal, and slant in unconfined aquifers affected from above by the unsaturated flow process.

  15. Capacity for Visual Features in Mental Rotation.

    Science.gov (United States)

    Xu, Yangqing; Franconeri, Steven L

    2015-08-01

    Although mental rotation is a core component of scientific reasoning, little is known about its underlying mechanisms. For instance, how much visual information can someone rotate at once? We asked participants to rotate a simple multipart shape, requiring them to maintain attachments between features and moving parts. The capacity of this aspect of mental rotation was strikingly low: Only one feature could remain attached to one part. Behavioral and eye-tracking data showed that this single feature remained "glued" via a singular focus of attention, typically on the object's top. We argue that the architecture of the human visual system is not suited for keeping multiple features attached to multiple parts during mental rotation. Such measurement of capacity limits may prove to be a critical step in dissecting the suite of visuospatial tools involved in mental rotation, leading to insights for improvement of pedagogy in science-education contexts. © The Author(s) 2015.

  16. The right-handed slanting of Arabidopsis thaliana roots is due to the combined effects of positive gravitropism, circumnutation and thigmotropism.

    Science.gov (United States)

    Migliaccio, F; Piconese, S; Tronelli, G

    2000-12-01

    When primary Arabidopsis roots grow down a tilted agar plate, they do not elongate following the gravitational vector along a straight line, but instead they slant noticeably to the right-hand. This process is seen mostly in the ecotypes Wassilewskjia and Landsberg, whereas it is attenuated in the ecotype Columbia, and in some mutants is even inverted. The origin of the slanting of Arabidopsis roots, that evidently constitutes a form of chirality, has so far not been sufficiently clarified. In the present paper we describe it as the general result of the cumulative effects of positive gravitropism, circumnutation and a thigmotropic obstacle-avoiding movement, and in particular, as the consequence of the alternating movement of circumnutation of the root to the right and to the left of the gravitational vector. This movement, which does not appear symmetrical in its nature, since the waves made to the right-hand are complete whereas those made to the left-hand are reduced or aborted, appears to be the reason for the observed slanting. In addition, evidence is furnished supporting the hypothesis that the strong left-handed cell-files torsion, seen in right-handed coiling roots, is not the consequence of a primary process, but of an artifact, and is due to the adjustment of the three dimensional root circumnutating helix to the flat two dimensional agar surface.

  17. All-solid-state thin film battery based on well-aligned slanted LiCoO2 nanowires fabricated by glancing angle deposition

    Science.gov (United States)

    Yoon, Miyoung; Lee, Seunghwan; Lee, Daehee; Kim, Joosun; Moon, Jooho

    2017-08-01

    We fabricated all-solid-state thin film batteries based on well-aligned slanted LiCoO2 nanowires by glancing angle deposition, as a facile template-free method in order to increase the electrochemically active site, i.e., the contact area between the solid electrolyte and the electrode. A highly porous thin film composed of well-separated slanted LiCoO2 nanowires not only facilitates the penetration of solid electrolyte phase into the cathode, but also alleviates the thermally and mechanically induced stresses during post-annealing and electrochemical cycling. The all-solid-state thin film battery based on the well-aligned slanted LiCoO2 nanowires, whose contact area between electrolyte and electrode was three times as high as that of a dense thin film, could provide additional migration pathways for lithium ion diffusion due to the enlarged reaction sites. This resulted in enhanced electrochemical kinetics, thereby leading to better rate capability and long-term cyclic stability as compared to the dense LiCoO2 thin film.

  18. Keeping It in Three Dimensions: Measuring the Development of Mental Rotation in Children with the Rotated Colour Cube Test (RCCT)

    Science.gov (United States)

    Lutke, Nikolay; Lange-Kuttner, Christiane

    2015-01-01

    This study introduces the new Rotated Colour Cube Test (RCCT) as a measure of object identification and mental rotation using single 3D colour cube images in a matching-to-sample procedure. One hundred 7- to 11-year-old children were tested with aligned or rotated cube models, distracters and targets. While different orientations of distracters…

  19. Influence of Substrate Moisture State and Roughness on Interface Microstructure and Bond Strength: Slant Shear vs. Pull-Off Testing.

    Science.gov (United States)

    Bentz, Dale P; De la Varga, Igor; Muñoz, Jose F; Spragg, Robert P; Graybeal, Benjamin A; Hussey, Daniel S; Jacobson, David L; Jones, Scott Z; LaManna, Jacob M

    2018-03-01

    There are conflicting views in the literature concerning the optimum moisture state for an existing substrate prior to the application of a repair material. Both saturated-surface-dry (SSD) and dry substrates have been found to be preferable in a variety of studies. One confounding factor is that some studies evaluate bonding of the repair material to the substrate via pull-off (direct tension) testing, while others have employed some form of shear specimens as their preferred testing configuration. Available evidence suggests that dry substrate specimens usually perform equivalently or better in shear testing, while SSD ones generally exhibit higher bond strengths when a pull-off test is performed, although exceptions to these trends have been observed. This paper applies a variety of microstructural characterization tools to investigate the interfacial microstructure that develops when a fresh repair material is applied to either a dry or SSD substrate. Simultaneous neutron and X-ray radiography are employed to observe the dynamic microstructural rearrangements that occur at this interface during the first 4 h of curing. Based on the differences in water movement and densification (particle compaction) that occur for the dry and SSD specimens, respectively, a hypothesis is formulated as to why different bond tests may favor one moisture state over the other, also dependent on their surface roughness. It is suggested that the compaction of particles at a dry substrate surface may increase the frictional resistance when tested under slant shear loading, but contribute relatively little to the bonding when the interface is submitted to pull-off forces. For maximizing bond performance, the fluidity of the repair material and the roughness and moisture state of the substrate must all be given adequate consideration.

  20. Muon spin rotation in solids

    Science.gov (United States)

    Stronach, C. E.

    1983-01-01

    The muon spin rotation (MuSR) technique is used to probe the microscopic electron density in materials. High temperature MuSR and magnetization measurements in nickel are in progress to allow an unambiguous determination of the muon impurity interaction and the impurity induced change in local spin density. The first results on uniaxial stress induced frequency shifts in an Fe single crystal are also reported.

  1. On Averaging Rotations

    DEFF Research Database (Denmark)

    Gramkow, Claus

    1999-01-01

    In this article two common approaches to averaging rotations are compared to a more advanced approach based on a Riemannian metric. Very offten the barycenter of the quaternions or matrices that represent the rotations are used as an estimate of the mean. These methods neglect that rotations belong...... approximations to the Riemannian metric, and that the subsequent corrections are inherient in the least squares estimation. Keywords: averaging rotations, Riemannian metric, matrix, quaternion...

  2. Parameterization of rotational spectra

    International Nuclear Information System (INIS)

    Zhou Chunmei; Liu Tong

    1992-01-01

    The rotational spectra of the strongly deformed nuclei with low rotational frequencies and weak band mixture are analyzed. The strongly deformed nuclei are commonly encountered in the rare-earth region (e. g., 150 220). A lot of rotational band knowledge are presented

  3. Rotating Stars in Relativity

    Directory of Open Access Journals (Sweden)

    Stergioulas Nikolaos

    2003-01-01

    Full Text Available Rotating relativistic stars have been studied extensively in recent years, both theoretically and observationally, because of the information they might yield about the equation of state of matter at extremely high densities and because they are considered to be promising sources of gravitational waves. The latest theoretical understanding of rotating stars in relativity is reviewed in this updated article. The sections on the equilibrium properties and on the nonaxisymmetric instabilities in f-modes and r-modes have been updated and several new sections have been added on analytic solutions for the exterior spacetime, rotating stars in LMXBs, rotating strange stars, and on rotating stars in numerical relativity.

  4. Visualizing molecular unidirectional rotation

    Science.gov (United States)

    Lin, Kang; Song, Qiying; Gong, Xiaochun; Ji, Qinying; Pan, Haifeng; Ding, Jingxin; Zeng, Heping; Wu, Jian

    2015-07-01

    We directly visualize the spatiotemporal evolution of a unidirectional rotating molecular rotational wave packet. Excited by two time-delayed polarization-skewed ultrashort laser pulses, the cigar- or disk-shaped rotational wave packet is impulsively kicked to unidirectionally rotate as a quantum rotor which afterwards disperses and exhibits field-free revivals. The rich dynamics can be coherently controlled by varying the timing or polarization of the excitation laser pulses. The numerical simulations very well reproduce the experimental observations and intuitively revivify the thoroughgoing evolution of the molecular rotational wave packet of unidirectional spin.

  5. Laboratory rotational spectrum of singly 13C-substituted dimethyl ether up to 1.5 THz and interstellar detection of 13CH_3O12CH_3 - a fruitful interplay between laboratory work and inter

    Science.gov (United States)

    Koerber, M.; Bisschop, S.; Endres, C.; Lewen, F.; Schlemmer, S.

    2011-05-01

    Dimethyl ether (CH_3OCH_3) is found in high abundance in star forming regions. However, the interstellar formation process of dimethyl ether still remains unclear up to now. In current gas-grain models gas-phase synthesis via self-methylation of methanol evaporating from grains is discussed in contrast to the surface reaction of CH_3 with successively hydrogenated CO (Garrod & Herbst 2006). An observational test for the formation mechanism has been proposed by Charnley et al. (2004) making use of the 13C fractionation into CO at low temperatures on grains: Comparing the 12C/13C ratio of molecules to the 12CO/13CO ratio allows to distinguish between formation from CO on cold grains and pure gas-phase formation routes. The isotopic ratio of species like dimethyl ether thus can be used as a tracer of the chemical evolution of the observed region. Due to its two methyl groups undergoing large amplitude motions and a relatively strong dipole moment of μ = 1.302 D it shows a strong and dense complex spectrum all over the terahertz region relevant for Herschel and ALMA observations. Accurate transition frequencies are needed to interpret the astronomical spectra. For the main isotopologue extensive data are now available (Endres et al. 2009). However, due to the greatly improved sensitivity of the new observatories isotopic species of abundant molecules like dimethyl ether are appearing in the spectra as well. In this work we present laboratory measurements of singly 13C-substituted dimethyl ether (13CH_3O12CH_3) up to 1.5 THz. More than 1700 transitions of 13CH_3O12CH_3 with rotational quantum numbers up to J = 53 and K = 25 have been analyzed. Based on the laboratory measurements singly 13C-substituted dimethyl ether has been detected for the first time in the spectrum of G327.3-0.6 (Bisschop et al. in prep.) and a preliminary value for the 12C/13C abundance ratio has been determined.

  6. Rotations in a Vertebrate Setting

    Science.gov (United States)

    McCollum, Gin

    2003-05-01

    Rotational movements of the head are often considered to be measured in a single three dimensional coordinate system implemented by the semicircular canals of the vestibular system of the inner ear. However, the vertebrate body -- including the nervous system -- obeys rectangular symmetries alien to rotation groups. At best, nervous systems mimic the physical rotation group in a fragmented way, only partially reintegrating physical movements in whole organism responses. The vestibular canal reference frame is widely used in nervous systems, for example by eye movements. It is used to some extent even in the cerebrum, as evidenced by the remission of hemineglect -- in which half of space is ignored -- when the vestibular system is stimulated. However, reintegration of space by the organism remains incomplete. For example, compensatory eye movements (which in most cases aid visual fixation) may disagree with conscious self-motion perception. In addition, movement-induced nausea, illusions, and cue-free perceptions demonstrate symmetry breaking or incomplete spatial symmetries. As part of a long-term project to investigate rotation groups in nervous systems, we have analyzed the symmetry group of a primary vestibulo-spinal projection.

  7. Analysis of counter-rotating wind turbines

    DEFF Research Database (Denmark)

    Shen, Wen Zhong; Zakkam, Vinod Arun Kumar; Sørensen, Jens Nørkær

    2007-01-01

    This paper presents a study on the performance of a wind turbine with two counter-rotating (CRWT) rotors. The characteristics of the two counter-rotating rotors are on a 3-bladed Nordtank 500 kW rotor. The analysis has been carried out by using an Actuator Line technique implemented in the Navier......-Stokes code EllipSys3D. The analysis shows that the Annual Energy Production can be increased to about 43.5 %, as compared to a wind turbine with a single rotor. In order to determine the optimal settings of the CRWT turbine, parameters such as distance between two rotors and rotational speed have been...

  8. Shape constancy and depth-order violations in structure from motion: A look at non-frontoparallel axes of rotation

    Science.gov (United States)

    Fernandez, Julian M.; Farell, Bart

    2007-01-01

    Humans can recover the structure of a 3D object from motion cues alone. Recovery of structure from motion (SFM) from the projected 2D motion field of a rotating object has been studied almost exclusively in one particular condition, that in which the axis of rotation lies in the frontoparallel plane. Here, we assess the ability of humans to recover SFM in the general case, where the axis of rotation may be slanted out of the frontoparallel plane. Using elliptical cylinders whose cross section was constant along the axis of rotation, we find that, across a range of parameters, subjects accurately matched the simulated shape of the cylinder regardless of how much the axis of rotation is inclined away from the frontoparallel plane. Yet, we also find that subjects do not perceive the inclination of the axis of rotation veridically. This combination of results violates a relationship between perceived angle of inclination and perceived shape that must hold if SFM is to be recovered from the instantaneous velocity field. The contradiction can be resolved if the angular speed of rotation is not consistently estimated from the instantaneous velocity field. This, in turn, predicts that variation in object size along the axis of rotation can cause depth-order violations along the line of sight. This prediction was verified using rotating circular cones as stimuli. Thus, as the axis of rotation changes its inclination, shape constancy is maintained through a trade-off. Humans perceive the structure of the object relative to a changing axis of rotation as unchanging by introducing an inconsistency between the perceived speed of rotation and the first-order optic flow. The observed depth-order violations are the cost of the trade-off. PMID:17685799

  9. Rotations with Rodrigues' vector

    International Nuclear Information System (INIS)

    Pina, E

    2011-01-01

    The rotational dynamics was studied from the point of view of Rodrigues' vector. This vector is defined here by its connection with other forms of parametrization of the rotation matrix. The rotation matrix was expressed in terms of this vector. The angular velocity was computed using the components of Rodrigues' vector as coordinates. It appears to be a fundamental matrix that is used to express the components of the angular velocity, the rotation matrix and the angular momentum vector. The Hamiltonian formalism of rotational dynamics in terms of this vector uses the same matrix. The quantization of the rotational dynamics is performed with simple rules if one uses Rodrigues' vector and similar formal expressions for the quantum operators that mimic the Hamiltonian classical dynamics.

  10. 2 kV slanted tri-gate GaN-on-Si Schottky barrier diodes with ultra-low leakage current

    Science.gov (United States)

    Ma, Jun; Matioli, Elison

    2018-01-01

    This letter reports lateral GaN-on-Si power Schottky barrier diodes (SBDs) with unprecedented voltage-blocking performance by integrating 3-dimensionally a hybrid of tri-anode and slanted tri-gate architectures in their anode. The hybrid tri-anode pins the voltage drop at the Schottky junction (VSCH), despite a large applied reverse bias, fixing the reverse leakage current (IR) of the SBD. Such architecture led to an ultra-low IR of 51 ± 5.9 nA/mm at -1000 V, in addition to a small turn-on voltage (VON) of 0.61 ± 0.03 V. The slanted tri-gate effectively distributes the electric field in OFF state, leading to a remarkably high breakdown voltage (VBR) of -2000 V at 1 μA/mm, constituting a significant breakthrough from existing technologies. The approach pursued in this work reduces the IR and increases the VBR without sacrificing the VON, which provides a technology for high-voltage SBDs, and unveils the unique advantage of tri-gates for advanced power applications.

  11. The spatial rotator

    DEFF Research Database (Denmark)

    Rasmusson, Allan; Hahn, Ute; Larsen, Jytte Overgaard

    2013-01-01

    This paper presents a new local volume estimator, the spatial rotator, which is based on measurements on a virtual 3D probe, using computer assisted microscopy. The basic design of the probe builds upon the rotator principle which requires only a few manual intersection markings, thus making...

  12. Units of rotational information

    Science.gov (United States)

    Yang, Yuxiang; Chiribella, Giulio; Hu, Qinheping

    2017-12-01

    Entanglement in angular momentum degrees of freedom is a precious resource for quantum metrology and control. Here we study the conversions of this resource, focusing on Bell pairs of spin-J particles, where one particle is used to probe unknown rotations and the other particle is used as reference. When a large number of pairs are given, we show that every rotated spin-J Bell state can be reversibly converted into an equivalent number of rotated spin one-half Bell states, at a rate determined by the quantum Fisher information. This result provides the foundation for the definition of an elementary unit of information about rotations in space, which we call the Cartesian refbit. In the finite copy scenario, we design machines that approximately break down Bell states of higher spins into Cartesian refbits, as well as machines that approximately implement the inverse process. In addition, we establish a quantitative link between the conversion of Bell states and the simulation of unitary gates, showing that the fidelity of probabilistic state conversion provides upper and lower bounds on the fidelity of deterministic gate simulation. The result holds not only for rotation gates, but also to all sets of gates that form finite-dimensional representations of compact groups. For rotation gates, we show how rotations on a system of given spin can simulate rotations on a system of different spin.

  13. Deconstructing Mental Rotation

    DEFF Research Database (Denmark)

    Larsen, Axel

    2014-01-01

    A random walk model of the classical mental rotation task is explored in two experiments. By assuming that a mental rotation is repeated until sufficient evidence for a match/mismatch is obtained, the model accounts for the approximately linearly increasing reaction times (RTs) on positive trials...

  14. The rotating universe

    International Nuclear Information System (INIS)

    Ruben, G.; Treder, H.J.

    1987-01-01

    For a long time the question whether the universe rotates or not is discussed. Aspects of Huygens, Newton, Mach and other important historical scientists in this field are reported. The investigations of the mathematician Kurt Groedel in order to prove the rotation of the universe are illustrated. Kurt Groedel has shown that Einstein's gravitational equations of general relativity theory and the cosmological postulate of global homogeneity of cosmic matter (that is the Copernical principle) are not contradictionary to a rotating universe. Abberation measurements, position determination by means of radiointerferometry and methods for the determination of the rotation of the universe from the isotropy of the background radiation are presented. From these experiments it can be concluded that the universe seems not to rotate as already Einstein expected

  15. Rotation sensor switch

    International Nuclear Information System (INIS)

    Sevec, J.B.

    1978-01-01

    A protective device to provide a warning if a piece of rotating machinery slows or stops is comprised of a pair of hinged weights disposed to rotate on a rotating shaft of the equipment. When the equipment is rotating, the weights remain in a plane essentially perpendicular to the shaft and constitute part of an electrical circuit that is open. When the shaft slows or stops, the weights are attracted to a pair of concentric electrically conducting disks disposed in a plane perpendicular to the shaft and parallel to the plane of the weights when rotating. A disk magnet attracts the weights to the electrically conducting plates and maintains the electrical contact at the plates to complete an electrical circuit that can then provide an alarm signal

  16. Rotating stars in relativity.

    Science.gov (United States)

    Paschalidis, Vasileios; Stergioulas, Nikolaos

    2017-01-01

    Rotating relativistic stars have been studied extensively in recent years, both theoretically and observationally, because of the information they might yield about the equation of state of matter at extremely high densities and because they are considered to be promising sources of gravitational waves. The latest theoretical understanding of rotating stars in relativity is reviewed in this updated article. The sections on equilibrium properties and on nonaxisymmetric oscillations and instabilities in f -modes and r -modes have been updated. Several new sections have been added on equilibria in modified theories of gravity, approximate universal relationships, the one-arm spiral instability, on analytic solutions for the exterior spacetime, rotating stars in LMXBs, rotating strange stars, and on rotating stars in numerical relativity including both hydrodynamic and magnetohydrodynamic studies of these objects.

  17. Rotational Laser Cooling of MgH+ Ions and Rotational Rate Measurements

    DEFF Research Database (Denmark)

    Hansen, Anders Kragh; Staanum, Peter; Højbjerre, Klaus

    A method of laser cooling vibrationally and translationally cold trapped MgH+ ions to the rotational ground state using optical pumping was recently demonstrated in our group [1]. This method relies on the 293 K blackbody radiation to redistribute population among the rotational states, while...... exciting a single rovibrational transition within the X1Σ+ electronic ground state for optical pumping into the rovibrational ground state. To model the expected rotational state distributions after the application of the laser beam, one has to know the various rotational transitions rates in the present...... blackbody radiation field. To undertake such modelling, we will carry out measurements of a series of transition rates between rotational states in the vibronic ground state at room temperature. The measurements will be performed by the same Resonance Enhanced Multi-Photon Dissociation (REMPD) process used...

  18. Molecular equilibrium structures from experimental rotational constants and calculated vibration-rotation interaction constants

    DEFF Research Database (Denmark)

    Pawlowski, F; Jorgensen, P; Olsen, Jeppe

    2002-01-01

    A detailed study is carried out of the accuracy of molecular equilibrium geometries obtained from least-squares fits involving experimental rotational constants B(0) and sums of ab initio vibration-rotation interaction constants alpha(r)(B). The vibration-rotation interaction constants have been...... calculated for 18 single-configuration dominated molecules containing hydrogen and first-row atoms at various standard levels of ab initio theory. Comparisons with the experimental data and tests for the internal consistency of the calculations show that the equilibrium structures generated using Hartree......-Fock vibration-rotation interaction constants have an accuracy similar to that obtained by a direct minimization of the CCSD(T) energy. The most accurate vibration-rotation interaction constants are those calculated at the CCSD(T)/cc-pVQZ level. The equilibrium bond distances determined from these interaction...

  19. INFORMATIONAL MODEL OF MENTAL ROTATION OF FIGURES

    Directory of Open Access Journals (Sweden)

    V. A. Lyakhovetskiy

    2016-01-01

    Full Text Available Subject of Study.The subject of research is the information structure of objects internal representations and operations over them, used by man to solve the problem of mental rotation of figures. To analyze this informational structure we considered not only classical dependencies of the correct answers on the angle of rotation, but also the other dependencies obtained recently in cognitive psychology. Method.The language of technical computing Matlab R2010b was used for developing information model of the mental rotation of figures. Such model parameters as the number of bits in the internal representation, an error probability in a single bit, discrete rotation angle, comparison threshold, and the degree of difference during rotation can be changed. Main Results.The model reproduces qualitatively such psychological dependencies as the linear increase of time of correct answers and the number of errors on the angle of rotation for identical figures, "flat" dependence of the time of correct answers and the number of errors on the angle of rotation for mirror-like figures. The simulation results suggest that mental rotation is an iterative process of finding a match between the two figures, each step of which can lead to a significant distortion of the internal representation of the stored objects. Matching is carried out within the internal representations that have no high invariance to rotation angle. Practical Significance.The results may be useful for understanding the role of learning (including the learning with a teacher in the development of effective information representation and operations on them in artificial intelligence systems.

  20. Rotatable seal assembly. [Patent application; rotating targets

    Science.gov (United States)

    Logan, C.M.; Garibaldi, J.L.

    1980-11-12

    An assembly is provided for rotatably supporting a rotor on a stator so that vacuum chambers in the rotor and stator remain in communication while the chambers are sealed from ambient air, which enables the use of a ball bearing or the like to support most of the weight of the rotor. The apparatus includes a seal device mounted on the rotor to rotate therewith, but shiftable in position on the rotor while being sealed to the rotor as by an O-ring. The seal device has a flat face that is biased towards a flat face on the stator, and pressurized air is pumped between the faces to prevent contact between them while spacing them a small distance apart to avoid the inflow of large amounts of air between the faces and into the vacuum chambers.

  1. A rotating quantum vacuum

    Energy Technology Data Exchange (ETDEWEB)

    Lorenci, V.A. de; Svaiter, N.F. [Centro Brasileiro de Pesquisas Fisicas (CBPF), Rio de Janeiro, RJ (Brazil)

    1996-11-01

    It was investigated which mapping has to be used to compare measurements made in a rotating frame to those made in an inertial frame. Using a non-Galilean coordinate transformation, the creation-annihilation operators of a massive scalar field in the rotating frame are not the same as those of an inertial observer. This leads to a new vacuum state(a rotating vacuum) which is a superposition of positive and negative frequency Minkowski particles. Polarization effects in circular accelerators in the proper frame of the electron making a connection with the inertial frame point of view were analysed. 65 refs.

  2. On Averaging Rotations

    DEFF Research Database (Denmark)

    Gramkow, Claus

    2001-01-01

    In this paper two common approaches to averaging rotations are compared to a more advanced approach based on a Riemannian metric. Very often the barycenter of the quaternions or matrices that represent the rotations are used as an estimate of the mean. These methods neglect that rotations belong...... to a non-linear manifold and re-normalization or orthogonalization must be applied to obtain proper rotations. These latter steps have been viewed as ad hoc corrections for the errors introduced by assuming a vector space. The article shows that the two approximative methods can be derived from natural...... approximations to the Riemannian metric, and that the subsequent corrections are inherent in the least squares estimation....

  3. Measurement of Unsteady Blade Surface Pressure on a Single Rotation Large Scale Advanced Prop-fan with Angular and Wake Inflow at Mach Numbers from 0.02 to 0.70

    Science.gov (United States)

    Bushnell, P.; Gruber, M.; Parzych, D.

    1988-01-01

    Unsteady blade surface pressure data for the Large-Scale Advanced Prop-Fan (LAP) blade operation with angular inflow, wake inflow and uniform flow over a range of inflow Mach numbers of 0.02 to 0.70 is provided. The data are presented as Fourier coefficients for the first 35 harmonics of shaft rotational frequency. Also presented is a brief discussion of the unsteady blade response observed at takeoff and cruise conditions with angular and wake inflow.

  4. Robot Grasps Rotating Object

    Science.gov (United States)

    Wilcox, Brian H.; Tso, Kam S.; Litwin, Todd E.; Hayati, Samad A.; Bon, Bruce B.

    1991-01-01

    Experimental robotic system semiautomatically grasps rotating object, stops rotation, and pulls object to rest in fixture. Based on combination of advanced techniques for sensing and control, constructed to test concepts for robotic recapture of spinning artificial satellites. Potential terrestrial applications for technology developed with help of system includes tracking and grasping of industrial parts on conveyor belts, tracking of vehicles and animals, and soft grasping of moving objects in general.

  5. Rotating universe models

    International Nuclear Information System (INIS)

    Tozini, A.V.

    1984-01-01

    A review is made of some properties of the rotating Universe models. Godel's model is identified as a generalized filted model. Some properties of new solutions of the Einstein's equations, which are rotating non-stationary Universe models, are presented and analyzed. These models have the Godel's model as a particular case. Non-stationary cosmological models are found which are a generalization of the Godel's metrics in an analogous way in which Friedmann is to the Einstein's model. (L.C.) [pt

  6. Electromagnetic rotational actuation.

    Energy Technology Data Exchange (ETDEWEB)

    Hogan, Alexander Lee

    2010-08-01

    There are many applications that need a meso-scale rotational actuator. These applications have been left by the wayside because of the lack of actuation at this scale. Sandia National Laboratories has many unique fabrication technologies that could be used to create an electromagnetic actuator at this scale. There are also many designs to be explored. In this internship exploration of the designs and fabrications technologies to find an inexpensive design that can be used for prototyping the electromagnetic rotational actuator.

  7. Passive RFID Rotation Dimension Reduction via Aggregation

    Science.gov (United States)

    Matthews, Eric

    Radio Frequency IDentification (RFID) has applications in object identification, position, and orientation tracking. RFID technology can be applied in hospitals for patient and equipment tracking, stores and warehouses for product tracking, robots for self-localisation, tracking hazardous materials, or locating any other desired object. Efficient and accurate algorithms that perform localisation are required to extract meaningful data beyond simple identification. A Received Signal Strength Indicator (RSSI) is the strength of a received radio frequency signal used to localise passive and active RFID tags. Many factors affect RSSI such as reflections, tag rotation in 3D space, and obstacles blocking line-of-sight. LANDMARC is a statistical method for estimating tag location based on a target tag's similarity to surrounding reference tags. LANDMARC does not take into account the rotation of the target tag. By either aggregating multiple reference tag positions at various rotations, or by determining a rotation value for a newly read tag, we can perform an expected value calculation based on a comparison to the k-most similar training samples via an algorithm called K-Nearest Neighbours (KNN) more accurately. By choosing the average as the aggregation function, we improve the relative accuracy of single-rotation LANDMARC localisation by 10%, and any-rotation localisation by 20%.

  8. Rotating superconductor magnet for producing rotating lobed magnetic field lines

    Science.gov (United States)

    Hilal, Sadek K.; Sampson, William B.; Leonard, Edward F.

    1978-01-01

    This invention provides a rotating superconductor magnet for producing a rotating lobed magnetic field, comprising a cryostat; a superconducting magnet in the cryostat having a collar for producing a lobed magnetic field having oppositely directed adjacent field lines; rotatable support means for selectively rotating the superconductor magnet; and means for energizing the superconductor magnet.

  9. Fluid flow and heat transfer in rotating porous media

    CERN Document Server

    Vadasz, Peter

    2016-01-01

    This Book concentrates the available knowledge on rotating fluid flow and heat transfer in porous media in one single reference. Dr. Vadasz develops the fundamental theory of rotating flow and heat transfer in porous media and introduces systematic classification and identification of the relevant problems. An initial distinction between rotating flows in isothermal heterogeneous porous systems and natural convection in homogeneous non-­‐isothermal porous systems provides the two major classes of problems to be considered. A few examples of solutions to selected problems are presented, highlighting the significant impact of rotation on the flow in porous media.

  10. Simultaneous Realization of Wavelength Conversion, 2R Regeneration, and All-Optical Multiple Logic Gates with OR, NOR, XOR, and XNOR Functions Based on Self-Polarization Rotation in a Single SOA: An Experimental Approach

    Directory of Open Access Journals (Sweden)

    Youssef Said

    2012-01-01

    Full Text Available We highlight the feasibility of experimental implementation of both inverted and noninverted wavelength conversion, 2R regeneration, and all-optical logic functions, such as OR, NOR, XOR, and XNOR optical gates by exploiting the self-polarization rotation in a semiconductor optical amplifier (SOA device without changing the setup configuration. Switching between each optical function is done by only adjusting the input optical power level. In order to allow optimum control and preserve the polarization state of the injected and collected signals, the polarimetric measures have been carried out in free space.

  11. Rotating positron tomographs revisited

    International Nuclear Information System (INIS)

    Townsend, D.; Defrise, M.; Geissbuhler, A.

    1994-01-01

    We have compared the performance of a PET scanner comprising two rotating arrays of detectors with that of the more conventional stationary-ring design. The same total number of detectors was used in each, and neither scanner had septa. For brain imaging, we find that the noise-equivalent count rate is greater for the rotating arrays by a factor of two. Rotating arrays have a sensitivity profile that peaks in the centre of the field of view, both axially and transaxially. In the transaxial plane, this effect offsets to a certain extent the decrease in the number of photons detected towards the centre of the brain due to self-absorption. We have also compared the performance of a rotating scanner to that of a full-ring scanner with the same number of rings. We find that a full-ring scanner with an axial extent of 16.2 cm (24 rings) is a factor of 3.5 more sensitive than a rotating scanner with 40% of the detectors and the same axial extent. (Author)

  12. The optical rotator

    DEFF Research Database (Denmark)

    Tandrup, T; Gundersen, Hans Jørgen Gottlieb; Jensen, Eva B. Vedel

    1997-01-01

    further discuss the methods derived from this principle and present two new local volume estimators. The optical rotator benefits from information obtained in all three dimensions in thick sections but avoids over-/ underprojection problems at the extremes of the cell. Using computer-assisted microscopes......The optical rotator is an unbiased, local stereological principle for estimation of cell volume and cell surface area in thick, transparent slabs, The underlying principle was first described in 1993 by Kieu Jensen (T. Microsc. 170, 45-51) who also derived an estimator of length, In this study we...... the extra measurements demand minimal extra effort and make this estimator even more efficient when it comes to estimation of individual cell size than many of the previous local estimators, We demonstrate the principle of the optical rotator in an example (the cells in the dorsal root ganglion of the rat...

  13. Coalescence of rotating black holes on Eguchi-Hanson space

    International Nuclear Information System (INIS)

    Matsuno, Ken; Ishihara, Hideki; Kimura, Masashi; Tomizawa, Shinya

    2007-01-01

    We obtain new charged rotating multi-black hole solutions on the Eguchi-Hanson space in the five-dimensional Einstein-Maxwell system with a Chern-Simons term and a positive cosmological constant. In the two-black holes case, these solutions describe the coalescence of two rotating black holes with the horizon topologies of S 3 into a single rotating black hole with the horizon topology of the lens space L(2;1)=S 3 /Z 2 . We discuss the differences in the horizon areas between our solutions and the two-centered Klemm-Sabra solutions which describe the coalescence of two rotating black holes with the horizon topologies of S 3 into a single rotating black hole with the horizon topology of S 3

  14. Rotational discontinuities and the structure of the magnetopause

    International Nuclear Information System (INIS)

    Swift, D.W.; Lee, L.C.

    1983-01-01

    Symmetric and asymmetric rotational discontinuities are studied by means of a one-dimensional computer simulation and by single-particle trajectory calculations. The numerical simulations show the symmetric rotation to be stable for both ion and electron senses of rotation with a thickness of the order of a few ion gyroradii when the rotation angle of the tangential field is 180 0 or less. Larger rotation angles tend to be unstable. In an expansive discontinuity, when the magnetic field on the downstream side of the discontinuity is larger, an expanding transition layer separating the high-field from a low-field region develops on the downstream side, and a symmetric rotational discontinuity forms at the upstream edge. The implication of these results for magnetopause structure and energy flow through the magnetopause is described

  15. Crop rotation modelling - A European model intercomparison

    DEFF Research Database (Denmark)

    Kollas, Chris; Kersebaum, Kurt C; Nendel, Claas

    2015-01-01

    crop growth simulation models to predict yields in crop rotations at five sites across Europe under minimal calibration. Crop rotations encompassed 301 seasons of ten crop types common to European agriculture and a diverse set of treatments (irrigation, fertilisation, CO2 concentration, soil types...... accurately than main crops (cereals). The majority of models performed better for the treatments of increased CO2 and nitrogen fertilisation than for irrigation and soil-related treatments. The yield simulation of the multi-model ensemble reduced the error compared to single-model simulations. The low degree...... representation of crop rotations, further research is required to synthesise existing knowledge of the physiology of intermediate crops and of carry-over effects from the preceding to the following crop, and to implement/improve the modelling of processes that condition these effects....

  16. Jet Engine Bird Ingestion Simulations: Comparison of Rotating to Non-Rotating Fan Blades

    Science.gov (United States)

    Howard, Samuel A.; Hammer, Jeremiah T.; Carney, Kelly S.; Pereira, J. Michael

    2013-01-01

    Bird strike events in commercial airliners are a fairly common occurrence. According to data collected by the US Department of Agriculture, over 80,000 bird strikes were reported in the period 1990 to 2007 in the US alone (Ref. 1). As a result, bird ingestion is an important factor in aero engine design and FAA certification. When it comes to bird impacts on engine fan blades, the FAA requires full-scale bird ingestion tests on an engine running at full speed to pass certification requirements. These rotating tests are complex and very expensive. To reduce development costs associated with new materials for fan blades, it is desirable to develop more cost effective testing procedures than full-scale rotating engine tests for material evaluation. An impact test on a nonrotating single blade that captures most of the salient physics of the rotating test would go a long way towards enabling large numbers of evaluative material screening tests. NASA Glenn Research Center has been working to identify a static blade test procedure that would be effective at reproducing similar results as seen in rotating tests. The current effort compares analytical simulations of a bird strike on various non-rotating blades to a bird strike simulation on a rotating blade as a baseline case. Several different concepts for simulating the rotating loads on a non-rotating blade were analyzed with little success in duplicating the deformation results seen in the rotating case. The rotating blade behaves as if it were stiffer than the non-rotating blade resulting in less plastic deformation from a given bird impact. The key factor limiting the success of the non-rotating blade simulations is thought to be the effect of gyroscopics. Prior to this effort, it was anticipated the difficulty would be in matching the prestress in the blade due to centrifugal forces Additional work is needed to verify this assertion, and to determine if a static test procedure can simulate the gyroscopic effects in

  17. Physician in Triage Versus Rotational Patient Assignment.

    Science.gov (United States)

    Traub, Stephen J; Bartley, Adam C; Smith, Vernon D; Didehban, Roshanak; Lipinski, Christopher A; Saghafian, Soroush

    2016-05-01

    Physician in triage and rotational patient assignment are different front-end processes that are designed to improve patient flow, but there are little or no data comparing them. To compare physician in triage with rotational patient assignment with respect to multiple emergency department (ED) operational metrics. Design-Retrospective cohort review. Patients-Patients seen on 23 days on which we utilized a physician in triage with those patients seen on 23 matched days when we utilized rotational patient assignment. There were 1,869 visits during physician in triage and 1,906 visits during rotational patient assignment. In a simple comparison, rotational patient assignment was associated with a lower median length of stay (LOS) than physician in triage (219 min vs. 233 min; difference of 14 min; 95% confidence interval [CI] 5-27 min). In a multivariate linear regression incorporating multiple confounders, there was a nonsignificant reduction in the geometric mean LOS in rotational patient assignment vs. physician in triage (204 min vs. 217 min; reduction of 6.25%; 95% CI -3.6% to 15.2%). There were no significant differences between groups for left before being seen, left subsequent to being seen, early (within 72 h) returns, early returns with admission, or complaint ratio. In a single-site study, there were no statistically significant differences in important ED operational metrics between a physician in triage model and a rotational patient assignment model after adjusting for confounders. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. Rotator Cuff Injuries.

    Science.gov (United States)

    Connors, G. Patrick

    Many baseball players suffer from shoulder injuries related to the rotator cuff muscles. These injuries may be classified as muscular strain, tendonitis or tenosynovitis, and impingement syndrome. Treatment varies from simple rest to surgery, so it is important to be seen by a physician as soon as possible. In order to prevent these injuries, the…

  19. Rotations and angular momentum

    International Nuclear Information System (INIS)

    Nyborg, P.; Froyland, J.

    1979-01-01

    This paper is devoted to the analysis of rotational invariance and the properties of angular momentum in quantum mechanics. In particular, the problem of addition of angular momenta is treated in detail, and tables of Clebsch-Gordan coefficients are included

  20. Rotating turbine blade pyrometer

    Science.gov (United States)

    Buchele, D. R.; Lesco, D. J.

    1974-01-01

    Non-contacting pyrometer system optically measures surface temperature distribution on rotating turbine blade, comprising line-by-line scan via fiber optic probe. Each scan line output is converted to digital signals, temporarily stored in buffer memory, and then processed in minicomputer for display as temperature.

  1. Can planetary nebulae rotate

    International Nuclear Information System (INIS)

    Grinin, V.P.

    1982-01-01

    It is shown that the inclination of spectral lines observed in a number of planetary nebulae when the spectrograph slit is placed along the major axis, which is presently ascribed to nonuniform expansion of the shells, actually may be due to rotation of the nebulae about their minor axes, as Campbell and Moore have suggested in their reports. It is assumed that the rotation of the central star (or, if the core is a binary system, circular motions of gas along quasi-Keplerian orbits) serves as the source of the original rotation of a protoplanetary nebula. The mechanism providing for strengthening of the original rotation in the process of expansion of the shell is the tangential pressure of L/sub α/ radiation due to the anisotropic properties of the medium and radiation field. The dynamic effect produced by them is evidently greatest in the epoch when the optical depth of the nebula in the L/sub c/ continuum becomes on the order of unity in the course of its expansion

  2. Rotational Dynamics with Tracker

    Science.gov (United States)

    Eadkhong, T.; Rajsadorn, R.; Jannual, P.; Danworaphong, S.

    2012-01-01

    We propose the use of Tracker, freeware for video analysis, to analyse the moment of inertia ("I") of a cylindrical plate. Three experiments are performed to validate the proposed method. The first experiment is dedicated to find the linear coefficient of rotational friction ("b") for our system. By omitting the effect of such friction, we derive…

  3. Midplane Faraday Rotation: A densitometer for BPX

    International Nuclear Information System (INIS)

    Jobes, F.C.; Mansfield, D.K.

    1992-02-01

    The density in a high field, high density tokamak such as BPX can be determined by measuring the Faraday rotation of a 10.6 μm laser directed tangent to the toroidal field. If there is a horizontal array of such beams, then n e (R) can be readily obtained with a simple Abel version about the center line of the tokamak. For BPX operated at full field and density, the rotation angle would be quite large -- about 75 degrees per pass. A layout in which a single laser beam is fanned out in the horizontal midplane of the tokamak, with a set of retroreflectors on the far side of the vacuum vessel, would provide good spatial resolution, depending only upon the number of reflectors. With this proposed layout, only one window would be needed. Because the rotation angle is never more than 1 ''fringe,'' the data is always good, and it is also a continuous measurement in time. Faraday rotation is dependent only upon the plasma itself, and thus is not sensitive to vibration of the optical components. Simulations of the expected results show that BPX would be well served even at low densities by a Midplane Faraday Rotation densitometer of ∼64 channels. Both TFTR and PBX-M would be suitable test beds for the BPX system

  4. Wave-driven Rotation in Supersonically Rotating Mirrors

    Energy Technology Data Exchange (ETDEWEB)

    A. Fetterman and N.J. Fisch

    2010-02-15

    Supersonic rotation in mirrors may be produced by radio frequency waves. The waves produce coupled diffusion in ion kinetic and potential energy. A population inversion along the diffusion path then produces rotation. Waves may be designed to exploit a natural kinetic energy source or may provide the rotation energy on their own. Centrifugal traps for fusion and isotope separation may benefit from this wave-driven rotation.

  5. Chaotic Rotation of a Towed Elliptical Cylinder

    OpenAIRE

    Weymouth, G D

    2013-01-01

    In this paper I consider the self-excited rotation of an elliptical cylinder towed in a viscous fluid as a canonical model of nonlinear fluid structure interactions with possible applications in the design of sensors and energy extraction devices. First, the self-excited ellipse system is shown to be analogous to the forced bistable oscillators studied in classic chaos theory. A single variable, the distance between the pivot and the centroid, governs the system bifurcation into bi-stability....

  6. Application of Synthetic Storm Technique for Diurnal and Seasonal Variation of Slant Path Ka-Band Rain Attenuation Time Series over a Subtropical Location in South Africa

    Directory of Open Access Journals (Sweden)

    J. S. Ojo

    2015-01-01

    Full Text Available As technology advances and more demands are on satellite services, rain-induced attenuation still creates one of the most damaging effects of the atmosphere on the quality of radio communication signals, especially those operating above 10 GHz. System designers therefore require statistical information on rain-induced attenuation over the coverage area in order to determine the appropriate transmitter and receiver characteristics to be adopted. This paper presents results on the time-varying rain characterization and diurnal variation of slant path rain attenuation in the Ka-band frequency simulated with synthetic storm techniques over a subtropical location in South Africa using 10-year rain rate time-series data. The analysis is based on the CDF of one-minute rain rate; time-series seasonal variation of rain rate observed over four time intervals: 00:00–06:00, 06:00–12:00, 12:00–18:00, and 18:00–24:00; diurnal fades margin; and diurnal variation of rain attenuation. Comparison was also made between the synthesized values and measured attenuation data. The predicted statistics are in good agreement with those obtained from the propagation beacon measurement in the area. The overall results will be needed for an acceptable planning that can effectively reduce the fade margin to a very low value for an optimum data communication over this area.

  7. Plasma-ion diagnostics using a newly designed differential-spectrum ion-energy analyzer with electrostatic slanted grids

    International Nuclear Information System (INIS)

    Sakamoto, Y.; Cho, T.; Hirata, M.; Yoshimura, T.; Makino, K.; Nakashima, Y.; Yatsu, K.; Tamano, T.

    1997-01-01

    Ion energies, temperatures, and ion-confining potentials in open-ended plasma-confinement devices are clearly measured with our newly designed ion-energy spectrometer. This energy spectrometer has specific structures with obliquely positioned multiple grids. Such a grid geometry makes it possible to separate ions and electrons completely. This electrostatic spectrometer also has the following characteristics: (1) no use of internal magnetic fields (being different from E parallel B spectrometers); and (2) the use of a simple single-channel collector plate for obtaining differential ion-energy spectra (being different from energy-integrated spectra using Faraday cups). These characteristics provide us with easy handling of the spectrometer including an easy alignment of the radially scannable spectrometer in a plasma-confinement device. (orig.)

  8. The Spatiale Rotator

    DEFF Research Database (Denmark)

    Rasmusson, Allan

    2009-01-01

    it is embedded and sectioned. This has the unfortunate side effect that all information about positioning within the object is lost for blocks and sections. For complex tissue, like the mammalian brain, this information is of utmost importance to ensure measurements are performed in the correct region......The inherent demand for unbiasedness for some stereological estimators imposes a demand of not only positional uniform randomness but also isotropic randomness, i.e. directional uniform randomness. In order to comply with isotropy, one must perform a random rotation of the object of interest before...... is obeyed by randomizing the orientation of the virtual probe itself within the thick section. Overall, the benefit is that positional information is kept for any block and section of the specimen. As the Spatial Rotator is a 3D probe, data must be gathered from sections thicker than 25 micro meters to form...

  9. Rotational Baroclinic Adjustment

    DEFF Research Database (Denmark)

    Holtegård Nielsen, Steen Morten

    the reciprocal of the socalled Coriolis parameter, and the length scale, which is known as the Rossby radius. Also, because of their limited width currents influenced by rotation are quite persistent. The flow which results from the introduction of a surface level discontinuity across a wide channel is discussed...... of the numerical model a mechanism for the generation of along-frontal instabilities and eddies is suggested. Also, the effect of an irregular bathymetry is studied.Together with observations of wind and water levels some of the oceanographical observations from the old lightvessels are used to study...... with the horizontal extent of many other parts of the Danish inland waters implies that the dynamics of these should also be discussed in terms of rotational effects....

  10. Asteroid rotation. IV

    International Nuclear Information System (INIS)

    Harris, A.W.; Young, J.W.

    1983-01-01

    The results from the year 1979 of an ongoing program of asteroid photometry at Table Mountain Observatory are presented. The results for 53 asteroids are summarized in a table, showing the number, name, opposition date, taxonomic class, diameter, absolute magnitude, mean absolute magnitude at zero phase angle and values of the absolute magnitude and linear phase coefficient derived from it, the rotation period in hours, peak-to-peak amplitude of variation, difference between mean and maximum brightness, and reliability index. Another table presents data on aspect and comparison stars, including brightness and distance data. Reliable rotation periods are reported for 22 asteroids for which no previous values are known. For seven asteroids, periods are reported which are revisions of previously reported values

  11. Rotational spectrum of tryptophan

    Energy Technology Data Exchange (ETDEWEB)

    Sanz, M. Eugenia, E-mail: maria.sanz@kcl.ac.uk; Cabezas, Carlos, E-mail: ccabezas@qf.uva.es; Mata, Santiago, E-mail: santiago.mata@uva.es; Alonso, Josè L., E-mail: jlalonso@qf.uva.es [Grupo de Espectroscopia Molecular (GEM), Edificio Quifima, Laboratorios de Espectroscopia y Bioespectroscopia, Unidad Asociada CSIC, Parque Científico Uva, Universidad de Valladolid, 47011 Valladolid (Spain)

    2014-05-28

    The rotational spectrum of the natural amino acid tryptophan has been observed for the first time using a combination of laser ablation, molecular beams, and Fourier transform microwave spectroscopy. Independent analysis of the rotational spectra of individual conformers has conducted to a definitive identification of two different conformers of tryptophan, with one of the observed conformers never reported before. The analysis of the {sup 14}N nuclear quadrupole coupling constants is of particular significance since it allows discrimination between structures, thus providing structural information on the orientation of the amino group. Both observed conformers are stabilized by an O–H···N hydrogen bond in the side chain and a N–H···π interaction forming a chain that reinforce the strength of hydrogen bonds through cooperative effects.

  12. Muon spin rotation studies

    Science.gov (United States)

    1984-01-01

    The bulk of the muon spin rotation research work centered around the development of the muon spin rotation facility at the Alternating Gradient Synchrotron (AGS) of Brookhaven National Laboratory (BNL). The collimation system was both designed and fabricated at Virginia State University. This improved collimation system, plus improvements in detectors and electronics enabled the acquisition of spectra free of background out to 15 microseconds. There were two runs at Brookhaven in 1984, one run was devoted primarily to beam development and the other run allowed several successful experiments to be performed. The effect of uniaxial strain on an Fe(Si) crystal at elevated temperature (360K) was measured and the results are incorporated herein. A complete analysis of Fe pulling data taken earlier is included.

  13. Rotations in Stability Operations

    Science.gov (United States)

    2012-04-25

    forces to the protected population .” An “ overwhelming presence” was essential to the initial success in Haiti and an “inadequate” number of troops was...stability operations until they achieve the endstate rather than rotating them allows the military to use overwhelming presence, successfully handle...must deploy a force that provides an overwhelming presence in the area of operations with the mission to achieve the endstate. 14. SUBJECT

  14. Restoration of motor control and proprioceptive and cutaneous sensation in humans with prior upper-limb amputation via multiple Utah Slanted Electrode Arrays (USEAs) implanted in residual peripheral arm nerves

    OpenAIRE

    Wendelken, Suzanne; Page, David M.; Davis, Tyler; Wark, Heather A. C.; Kluger, David T.; Duncan, Christopher; Warren, David J.; Hutchinson, Douglas T.; Clark, Gregory A.

    2017-01-01

    Background Despite advances in sophisticated robotic hands, intuitive control of and sensory feedback from these prostheses has been limited to only 3-degrees-of-freedom (DOF) with 2 sensory percepts in closed-loop control. A Utah Slanted Electrode Array (USEA) has been used in the past to provide up to 81 sensory percepts for human amputees. Here, we report on the advanced capabilities of multiple USEAs implanted in the residual peripheral arm nerves of human amputees for restoring control o...

  15. Rotating clusters in nuclei

    International Nuclear Information System (INIS)

    Pauling, L.; Robinson, A.B.

    1975-01-01

    Values of R, the radius of rotation of the rotating cluster, are calculated from the energy of the lowest 2 + level of even-even nuclei with the assumption that the cluster consists of p 2 or n 2 respectively, for N or P magic, and of a helion (α) for N or P differing from a magic number by +-2. The values as a function of A show a zigzag course, which is correlated with the polyspheron structure of the nuclei. If the mantle is not overcrowded the cluster glides over the surface of the mantle and the value of R increases by one spheron diameter, about 3.2 fm. At certain values of N a change in structure of the nucleus occurs, with increase in radius of the core by half a spheron diameter, permitting the cluster to drop back into the mantle, with decrease in R by half a spheron diameter. In the lanthanon region of permanent prolate deformation the rotating cluster is a polyhelion, containing the number of helions permitted by the difference between Z or N and the nearest magic number, and in the actinon region it contains all the nucleons beyond 208 Pb, with maximum p 10 n 16 . An explanation is given of the difference between these regions. (author)

  16. Snakes and spin rotators

    International Nuclear Information System (INIS)

    Lee, S.Y.

    1990-01-01

    The generalized snake configuration offers advantages of either shorter total snake length and smaller orbit displacement in the compact configuration or the multi-functions in the split configuration. We found that the compact configuration can save about 10% of the total length of a snake. On other hand, the spilt snake configuration can be used both as a snake and as a spin rotator for the helicity state. Using the orbit compensation dipoles, the spilt snake configuration can be located at any distance on both sides of the interaction point of a collider provided that there is no net dipole rotation between two halves of the snake. The generalized configuration is then applied to the partial snake excitation. Simple formula have been obtained to understand the behavior of the partial snake. Similar principle can also be applied to the spin rotators. We also estimate the possible snake imperfections are due to various construction errors of the dipole magnets. Accuracy of field error of better than 10 -4 will be significant. 2 refs., 5 figs

  17. Coordinate-Free Rotation Operator.

    Science.gov (United States)

    Leubner, C.

    1979-01-01

    Suggests the use of a coordinate-free rotation operator for the teaching of rotations in Euclidean three space because of its twofold didactic advantage. Illustrates the potentialities of the coordinate-free rotation operator approach by a number of examples. (Author/GA)

  18. Rotating plug bearing and seal

    International Nuclear Information System (INIS)

    Wade, E.E.

    1977-01-01

    Disclosed is a bearing and seal structure for nuclear reactors utilizing rotating plugs above the nuclear reactor vessel. The structure permits lubrication of bearings and seals of the rotating plugs without risk of the lubricant draining into the reactor vessel below. The structure permits lubrication by utilizing a rotating outer race bearing. 19 claims, 3 figures

  19. COMMISSIONING SPIN ROTATORS IN RHIC

    International Nuclear Information System (INIS)

    MACKAY, W.W.; AHRENS, L.; BAI, M.; COURANT, E.D.; FISCHER, W.; HUANG, H.; LUCCIO, A.; MONTAG, C.; PILAT, F.; PTITSYN, V.; ROSER, T.; SATOGATA, T.; TRBOJEVIC, D.; VANZIEJTS, J.

    2003-01-01

    During the summer of 2002, eight superconducting helical spin rotators were installed into RHIC in order to control the polarization directions independently at the STAR and PHENIX experiments. Without the rotators, the orientation of polarization at the interaction points would only be vertical. With four rotators around each of the two experiments, we can rotate either or both beams from vertical into the horizontal plane through the interaction region and then back to vertical on the other side. This allows independent control for each beam with vertical, longitudinal, or radial polarization at the experiment. In this paper, we present results from the first run using the new spin rotators at PHENIX

  20. CISM Course on Rotating Fluids

    CERN Document Server

    1992-01-01

    The volume presents a comprehensive overview of rotation effects on fluid behavior, emphasizing non-linear processes. The subject is introduced by giving a range of examples of rotating fluids encountered in geophysics and engineering. This is then followed by a discussion of the relevant scales and parameters of rotating flow, and an introduction to geostrophic balance and vorticity concepts. There are few books on rotating fluids and this volume is, therefore, a welcome addition. It is the first volume which contains a unified view of turbulence in rotating fluids, instability and vortex dynamics. Some aspects of wave motions covered here are not found elsewhere.

  1. Visualization of Thomas–Wigner Rotations

    Directory of Open Access Journals (Sweden)

    Georg Beyerle

    2017-11-01

    Full Text Available It is well known that a sequence of two non-collinear Lorentz boosts (pure Lorentz transformations does not correspond to a Lorentz boost, but involves a spatial rotation, the Wigner or Thomas–Wigner rotation. We visualize the interrelation between this rotation and the relativity of distant simultaneity by moving a Born-rigid object on a closed trajectory in several steps of uniform proper acceleration. Born-rigidity implies that the stern of the boosted object accelerates faster than its bow. It is shown that at least five boost steps are required to return the object’s center to its starting position, if in each step the center is assumed to accelerate uniformly and for the same proper time duration. With these assumptions, the Thomas–Wigner rotation angle depends on a single parameter only. Furthermore, it is illustrated that accelerated motion implies the formation of a “frame boundary”. The boundaries associated with the five boosts constitute a natural barrier and ensure the object’s finite size.

  2. Ultrasensitive magnetometers based on rotational magnetic excitation

    International Nuclear Information System (INIS)

    Hristoforou, E.; Svec, P. Sr.

    2014-01-01

    Three new types of fluxgate magnetometers are presented in this paper, able to monitor the three components of the ambient field, all of them based on the principle of rotational excitation field. The first type is based on Yttrium- Iron Garnet (YIG) single crystal film, magnetized with rotational field on its plane, where the 2 nd , 4 th and 6 th harmonics offer the three components of the ambient field with sensitivity better than 1 pT at 0.2 Hz, its size being 25 cm 3 . The second type is based on permalloy film, where the rotational excitation field on its plane offers change of magnetoresistance with sensitivity better than 10 pT at 1 Hz, uncertainty of 1 ppm and size ∼ 8 cm 3 . The third type, is based on amorphous film, where the rotation field mode offer sensitivity better than 100 pT at 1 Hz, uncertainty of 10 ppm and size ∼ 10 mm 3 . (authors)

  3. Ultraspinning instability of rotating black holes

    International Nuclear Information System (INIS)

    Dias, Oscar J. C.; Figueras, Pau; Monteiro, Ricardo; Santos, Jorge E.

    2010-01-01

    Rapidly rotating Myers-Perry black holes in d≥6 dimensions were conjectured to be unstable by Emparan and Myers. In a previous publication, we found numerically the onset of the axisymmetric ultraspinning instability in the singly spinning Myers-Perry black hole in d=7, 8, 9. This threshold also signals a bifurcation to new branches of axisymmetric solutions with pinched horizons that are conjectured to connect to the black ring, black Saturn and other families in the phase diagram of stationary solutions. We firmly establish that this instability is also present in d=6 and in d=10, 11. The boundary conditions of the perturbations are discussed in detail for the first time, and we prove that they preserve the angular velocity and temperature of the original Myers-Perry black hole. This property is fundamental to establishing a thermodynamic necessary condition for the existence of this instability in general rotating backgrounds. We also prove a previous claim that the ultraspinning modes cannot be pure gauge modes. Finally we find new ultraspinning Gregory-Laflamme instabilities of rotating black strings and branes that appear exactly at the critical rotation predicted by the aforementioned thermodynamic criterium. The latter is a refinement of the Gubser-Mitra conjecture.

  4. Rotating electrical machines

    CERN Document Server

    Le Doeuff, René

    2013-01-01

    In this book a general matrix-based approach to modeling electrical machines is promulgated. The model uses instantaneous quantities for key variables and enables the user to easily take into account associations between rotating machines and static converters (such as in variable speed drives).   General equations of electromechanical energy conversion are established early in the treatment of the topic and then applied to synchronous, induction and DC machines. The primary characteristics of these machines are established for steady state behavior as well as for variable speed scenarios. I

  5. Rotating specimen rack repair

    International Nuclear Information System (INIS)

    Miller, G.E.; Rogers, P.J.; Nabor, W.G.; Bair, H.

    1984-01-01

    In 1980, an operator at the UCI TRIGA Reactor noticed difficulties with the rotation of the specimen rack. Investigations showed that the drive bearing in the rack had failed and allowed the bearings to enter the rack. After some time of operation in static mode it was decided that installation of a bearing substitute - a graphite sleeve - would be undertaken. Procedures were written and approved for removal of the rack, fabrication and installation of the sleeve, and re-installation of the rack. This paper describes these procedures in some detail. Detailed drawings of the necessary parts may be obtained from the authors

  6. Optical fiber rotation sensing

    CERN Document Server

    Burns, William K; Kelley, Paul

    1993-01-01

    Optical Fiber Rotation Sensing is the first book devoted to Interferometric Fiber Optic Gyros (IFOG). This book provides a complete overview of IFOGs, beginning with a historical review of IFOG development and including a fundamental exposition of basic principles, a discussion of devices and components, and concluding with industry reports on state-of-the-art activity. With several chapters contributed by principal developers of this solid-state device, the result is an authoritative work which will serve as the resource for researchers, students, and users of IFOGs.* * State-of-t

  7. Rotational Spectrum of Saccharine

    Science.gov (United States)

    Alonso, Elena R.; Mata, Santiago; Alonso, José L.

    2017-06-01

    A significant step forward in the structure-activity relationships of sweeteners was the assignment of the AH-B moiety in sweeteners by Shallenberger and Acree. They proposed that all sweeteners contain an AH-B moiety, known as glucophore, in which A and B are electronegative atoms separated by a distance between 2.5 to 4 Å. H is a hydrogen atom attached to one of the electronegative atom by a covalent bond. For saccharine, one of the oldest artificial sweeteners widely used in food and drinks, two possible B moieties exist ,the carbonyl oxygen atom and the sulfoxide oxygen atom although there is a consensus of opinion among scientists over the assignment of AH-B moieties to HN-SO. In the present work, the solid of saccharine (m.p. 220°C) has been vaporized by laser ablation (LA) and its rotational spectrum has been analyzed by broadband CP-FTMW and narrowband MB-FTMW Fourier transform microwave techniques. The detailed structural information extracted from the rotational constants and ^{14}N nuclear quadrupole coupling constants provided enough information to ascribe the glucophore's AH and B sites of saccharine. R. S. Shallenberger, T. E. Acree. Nature 216, 480-482 Nov 1967. R. S. Shallenberger. Taste Chemistry; Blackie Academic & Professional, London, (1993).

  8. Femoral rotation unpredictably affects radiographic anatomical lateral distal femoral angle measurements

    DEFF Research Database (Denmark)

    Miles, James Edward

    2016-01-01

    Objective: To describe the effects of internal and external femoral rotation on radiographic measurements of the anatomical lateral distal femoral angle (a-LDFA) using two methods for defining the anatomical proximal femoral axis (a-PFA). Methods: Digital radiographs were obtained of 14 right...... femora at five degree intervals from 10° external rotation to 10° internal rotation. Using freely available software, a-LDFA measurements were made using two different a-PFA by a single observer on one occasion. Results: Mean a-LDFA was significantly greater at 10° external rotation than at any other...... rotation. The response of individual femora to rotation was unpredictable, although fairly stable within ±5° of zero rotation. Mean a-LDFA for the two a-PFA methods differed by 1.5°, but were otherwise similarly affected by femoral rotation. Clinical significance: If zero femoral elevation can be achieved...

  9. Actomyosin contractility rotates the cell nucleus

    Science.gov (United States)

    Kumar, Abhishek; Maitra, Ananyo; Sumit, Madhuresh; Ramaswamy, Sriram; Shivashankar, G. V.

    2014-01-01

    The cell nucleus functions amidst active cytoskeletal filaments, but its response to their contractile stresses is largely unexplored. We study the dynamics of the nuclei of single fibroblasts, with cell migration suppressed by plating onto micro-fabricated patterns. We find the nucleus undergoes noisy but coherent rotational motion. We account for this observation through a hydrodynamic approach, treating the nucleus as a highly viscous inclusion residing in a less viscous fluid of orientable filaments endowed with active stresses. Lowering actin contractility selectively by introducing blebbistatin at low concentrations drastically reduced the speed and coherence of the angular motion of the nucleus. Time-lapse imaging of actin revealed a correlated hydrodynamic flow around the nucleus, with profile and magnitude consistent with the results of our theoretical approach. Coherent intracellular flows and consequent nuclear rotation thus appear to be an intrinsic property of cells. PMID:24445418

  10. Realization of mechanical rotation in superfluid helium

    Science.gov (United States)

    Gordon, E. B.; Kulish, M. I.; Karabulin, A. V.; Matyushenko, V. I.; Dyatlova, E. V.; Gordienko, A. S.; Stepanov, M. E.

    2017-09-01

    The possibility of using miniaturized low-power electric motors submerged in superfluid helium for organization of rotation inside a cryostat has been investigated. It has been revealed that many of commercial micromotors can operate in liquid helium consuming low power. Turret with 5 sample holders, assembled on the base of stepper motor, has been successfully tested in experiments on the nanowire production in quantized vortices of superfluid helium. Application of the stepper motor made it possible in a single experiment to study the effect of various experimental parameters on the yield and quality of the nanowires. The promises for continuous fast rotation of the bath filled by superfluid helium by using high-speed brushless micromotor were outlined and tested. Being realized, this approach will open new possibility to study the guest particles interaction with the array of parallel linear vortices in He II.

  11. Lunar Rotation, Orientation and Science

    Science.gov (United States)

    Williams, J. G.; Ratcliff, J. T.; Boggs, D. H.

    2004-12-01

    The Moon is the most familiar example of the many satellites that exhibit synchronous rotation. For the Moon there is Lunar Laser Ranging measurements of tides and three-dimensional rotation variations plus supporting theoretical understanding of both effects. Compared to uniform rotation and precession the lunar rotational variations are up to 1 km, while tidal variations are about 0.1 m. Analysis of the lunar variations in pole direction and rotation about the pole gives moment of inertia differences, third-degree gravity harmonics, tidal Love number k2, tidal dissipation Q vs. frequency, dissipation at the fluid-core/solid-mantle boundary, and emerging evidence for an oblate boundary. The last two indicate a fluid core, but a solid inner core is not ruled out. Four retroreflectors provide very accurate positions on the Moon. The experience with the Moon is a starting point for exploring the tides, rotation and orientation of the other synchronous bodies of the solar system.

  12. Isotope separation by rotating plasmas

    International Nuclear Information System (INIS)

    Nicoli, C.

    1982-02-01

    A steady-state model of a fully ionized plasma column in a concentric cylindrical electrodes structures is proposed to study the plasma separation properties of its singly ionized ionic species, composed of two isotopes of the element. In this model (a one-fluid model) rotation is imparted to the plasma column through the J (vector) x B (vector) interaction. Radial pressure balance is mainly between the radial component of the J (vector) x B (vector) force and the pressure gradient plus centrifugal force and the azimutal component of the J (vector) x B (vector) force is balanced purely by viscous force. A pressure tensor 31 describes the viscoys effect and the heat balance provides an equation for temperature. A uranium gas with is two main isotopes (U 235 and U 238 ) was used for the ionic component of the plasma. The computing code to solve the resulting, system of equations in tems of density, temperature, and velocity as functions of the radial independent variable was set up to yield solutions satisfying null velocity conditions on both boundaries (inner and outer electrodes). (M.A.F.) [pt

  13. Earth's variable rotation

    Science.gov (United States)

    Hide, Raymond; Dickey, Jean O.

    1991-01-01

    Recent improvements in geodetic data and practical meteorology have advanced research on fluctuations in the earth's rotation. The interpretation of these fluctuations is inextricably linked with studies of the dynamics of the earth-moon system and dynamical processes in the liquid metallic core of the earth (where the geomagnetic field originates), other parts of the earth's interior, and the hydrosphere and atmosphere. Fluctuations in the length of the day occurring on decadal time scales have implications for the topographay of the core-mantle boundary and the electrical, magnetic, ande other properties of the core and lower mantle. Investigations of more rapid fluctuations bear on meteorological studies of interannual, seasonal, and intraseasonal variations in the general circulation of the atmosphere and the response of the oceans to such variations.

  14. The Rapidly Rotating Sun

    Science.gov (United States)

    Hanasoge, Shravan M.; Duvall, Thomas L., Jr.; Sreenivasan, Katepalli R.

    2012-01-01

    Convection in the solar interior is thought to comprise structures at a continuum of scales, from large to small. This conclusion emerges from phenomenological studies and numerical simulations though neither covers the proper range of dynamical parameters of solar convection. In the present work, imaging techniques of time-distance helioseismology applied to observational data reveal no long-range order in the convective motion. We conservatively bound the associated velocity magnitudes, as a function of depth and the spherical-harmonic degree l to be 20-100 times weaker than prevailing estimates within the wavenumber band l ux of a solar luminosity outwards? The Sun is seemingly a much faster rotator than previously thought, with advection dominated by Coriolis forces at scales l < 60.

  15. Rotations, quaternions, and double groups

    CERN Document Server

    Altmann, Simon L

    2005-01-01

    This self-contained text presents a consistent description of the geometric and quaternionic treatment of rotation operators, employing methods that lead to a rigorous formulation and offering complete solutions to many illustrative problems.Geared toward upper-level undergraduates and graduate students, the book begins with chapters covering the fundamentals of symmetries, matrices, and groups, and it presents a primer on rotations and rotation matrices. Subsequent chapters explore rotations and angular momentum, tensor bases, the bilinear transformation, projective representations, and the g

  16. Structural, magnetic and magnetocaloric properties of La{sub 0.8}Ba{sub 0.2}Mn{sub 1-x}Fe{sub x}O{sub 3} compounds with 0 Less-Than-Or-Slanted-Equal-To x Less-Than-Or-Slanted-Equal-To 0.1

    Energy Technology Data Exchange (ETDEWEB)

    Ghodhbane, S., E-mail: godhbane.sana@gmail.com [Laboratoire de la matiere condensee et des nanosciences, Departement de Physique, Faculte des Sciences, Universite de Monastir, Monastir 5019 (Tunisia); Dhahri, A.; Dhahri, N. [Laboratoire de la matiere condensee et des nanosciences, Departement de Physique, Faculte des Sciences, Universite de Monastir, Monastir 5019 (Tunisia); Hlil, E.K. [Institut Neel, CNRS-Universite J. Fourier, BP 166, 38042 Gronoble (France); Dhahri, J. [Laboratoire de la matiere condensee et des nanosciences, Departement de Physique, Faculte des Sciences, Universite de Monastir, Monastir 5019 (Tunisia)

    2013-02-15

    Highlights: Black-Right-Pointing-Pointer The prepared samples exhibit paramagnetic-ferromagnetic phase transition (T{sub C}). Black-Right-Pointing-Pointer La{sub 0.8}Ba{sub 0.2}MnO{sub 3} exhibits the highest value of 4.15 J/(K kg) for T{sub C} = 295 K. Black-Right-Pointing-Pointer The field dependence of {Delta}S{sub M} change is also analyzed showing the power law dependence. Black-Right-Pointing-Pointer Critical behavior of the transition for manganites is sensitive to the Mn-site. - Abstract: The present study reports the effect of Fe doping on the structural, magnetic and magnetocaloric proprieties in the La{sub 0.8}Ba{sub 0.2}Mn{sub 1-x}Fe{sub x}O{sub 3} (0 Less-Than-Or-Slanted-Equal-To x Less-Than-Or-Slanted-Equal-To 0.1) perovskites. The studied samples were synthesized as powder samples by solid state reaction at high temperature. Their analysis by powder X-ray diffraction using Rietveld refinement showed that they crystallize in the rhombohedral system with the R3{sup Macron }C space group. They display a paramagnetic (PM)-ferromagnetic (FM) phase transition with decreasing temperature. All of them exhibit a maximum and large magnetocaloric effect near the Curie temperature (T{sub C}). The magnitude of the isothermal magnetic entropy |{Delta}S{sub M}{sup max}| at the FM Curie temperature decreases from 4.15 J kg{sup -1} K{sup -1} for the x = 0 composition to 2.62 J kg{sup -1} K{sup -1} for x = 0.1, for a magnetic field change of 5T. For an applied magnetic field of 5T, the relative cooling power (RCP) values are found to vary between 211 and 238 J kg{sup -1}. The phenomenon of large entropy change and the convenient adjustment of the Curie temperature make these peroskite-type manganese oxides useful for magnetic refrigeration in an extended high temperature range even at room temperature.

  17. Surface dimpling on rotating work piece using rotation cutting tool

    Science.gov (United States)

    Bhapkar, Rohit Arun; Larsen, Eric Richard

    2015-03-31

    A combined method of machining and applying a surface texture to a work piece and a tool assembly that is capable of machining and applying a surface texture to a work piece are disclosed. The disclosed method includes machining portions of an outer or inner surface of a work piece. The method also includes rotating the work piece in front of a rotating cutting tool and engaging the outer surface of the work piece with the rotating cutting tool to cut dimples in the outer surface of the work piece. The disclosed tool assembly includes a rotating cutting tool coupled to an end of a rotational machining device, such as a lathe. The same tool assembly can be used to both machine the work piece and apply a surface texture to the work piece without unloading the work piece from the tool assembly.

  18. Dynamic rotating-shield brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Yunlong [Department of Electrical and Computer Engineering, University of Iowa, 4016 Seamans Center, Iowa City, Iowa 52242 (United States); Flynn, Ryan T.; Kim, Yusung [Department of Radiation Oncology, University of Iowa, 200 Hawkins Drive, Iowa City, Iowa 52242 (United States); Yang, Wenjun [Department of Medical Physics, University of Wisconsin-Madison, 1111 Highland Avenue, Madison, Wisconsin 53705 (United States); Wu, Xiaodong [Department of Electrical and Computer Engineering, University of Iowa, 4016 Seamans Center, Iowa City, Iowa 52242 and Department of Radiation Oncology, University of Iowa, 200 Hawkins Drive, Iowa City, Iowa 52242 (United States)

    2013-12-15

    Purpose: To present dynamic rotating shield brachytherapy (D-RSBT), a novel form of high-dose-rate brachytherapy (HDR-BT) with electronic brachytherapy source, where the radiation shield is capable of changing emission angles during the radiation delivery process.Methods: A D-RSBT system uses two layers of independently rotating tungsten alloy shields, each with a 180° azimuthal emission angle. The D-RSBT planning is separated into two stages: anchor plan optimization and optimal sequencing. In the anchor plan optimization, anchor plans are generated by maximizing the D{sub 90} for the high-risk clinical-tumor-volume (HR-CTV) assuming a fixed azimuthal emission angle of 11.25°. In the optimal sequencing, treatment plans that most closely approximate the anchor plans under the delivery-time constraint will be efficiently computed. Treatment plans for five cervical cancer patients were generated for D-RSBT, single-shield RSBT (S-RSBT), and {sup 192}Ir-based intracavitary brachytherapy with supplementary interstitial brachytherapy (IS + ICBT) assuming five treatment fractions. External beam radiotherapy doses of 45 Gy in 25 fractions of 1.8 Gy each were accounted for. The high-risk clinical target volume (HR-CTV) doses were escalated such that the D{sub 2cc} of the rectum, sigmoid colon, or bladder reached its tolerance equivalent dose in 2 Gy fractions (EQD2 with α/β= 3 Gy) of 75 Gy, 75 Gy, or 90 Gy, respectively.Results: For the patients considered, IS + ICBT had an average total dwell time of 5.7 minutes/fraction (min/fx) assuming a 10 Ci{sup 192}Ir source, and the average HR-CTV D{sub 90} was 78.9 Gy. In order to match the HR-CTV D{sub 90} of IS + ICBT, D-RSBT required an average of 10.1 min/fx more delivery time, and S-RSBT required 6.7 min/fx more. If an additional 20 min/fx of delivery time is allowed beyond that of the IS + ICBT case, D-RSBT and S-RSBT increased the HR-CTV D{sub 90} above IS + ICBT by an average of 16.3 Gy and 9.1 Gy, respectively

  19. Black holes: a slanted overview

    International Nuclear Information System (INIS)

    Vishveshwara, C.V.

    1988-01-01

    The black hole saga spanning some seventy years may be broadly divided into four phases, namely, (a) the dark ages when little was known about black holes even though they had come into existence quite early through the Schwarzschild solution, (b) the age of enlightenment bringing in deep and prolific discoveries, (c) the age of fantasy that cast black holes in all sorts of extraordinary roles, and (d) the golden age of relativistic astrophysics - to some extent similar to Dirac's characterisation of the development of quantum theory - in which black holes have been extensively used to elucidate a number of astrophysical phenomena. It is impossible to give here even the briefest outline of the major developments in this vast area. We shall only attempt to present a few aspects of black hole physics which have been actively pursued in the recent past. Some details are given in the case of those topics that have not found their way into text books or review articles. (author)

  20. Slanting Design: A Pilot Program

    Science.gov (United States)

    1985-10-01

    adequate financing and proper planning and forethought. itG’ven the significant number of variables over which FEMA has no control , however, it would...Eskilstuna SWEDEN Ministero dell Interno Direzione Generale della Protezione Civile 00100 Rome ITALY Directeur de la Protection: Civile Ministere de

  1. Rotation of the planet mercury.

    Science.gov (United States)

    Jefferys, W H

    1966-04-08

    The equations of motion for the rotation of Mercury are solved for the general case by an asymptotic expansion. The findings of Liu and O'Keefe, obtained by numerical integration of a special case, that it is possible for Mercury's rotation to be locked into a 2:3 resonance with its revolution, are confirmed in detail. The general solution has further applications.

  2. Optical isolation by Faraday rotator

    International Nuclear Information System (INIS)

    Kasai, Takeshi; Matsushima, Isao; Nemoto, Fusashi; Yano, Masaaki

    1984-01-01

    Three Faraday rotators designed as optical isolators in a high power glass laser system are described. The spatial fluctuation of applied magnetic field is less than 1% throughout the Faraday glass rod. The Faraday rotators transmit more than 80% of the forward-going laser light and reject more than 96% of the backward-going light. (author)

  3. Vortex suppression in the wake of counter rotating cylinders

    Science.gov (United States)

    Dewey, Peter; Smits, Alexander J.

    2009-11-01

    Digital particle image velocimetry is used to study the flow past a pair of counter rotating cylinders placed side-by-side normal to the freestream flow direction. The Reynolds numbers based on cylinder diameter is varied from 100 to 200 and gap-to-diameter ratios of 1, 3 and 5 are considered. An unsteady wake consisting of a pair of von K'arm'an vortex streets is present in the flow field when the cylinders are rotated below a critical value. Above this critical value, counter rotation of the cylinders suppresses vortex formation. The critical rotational speed varies only slightly with Reynolds number but exhibits a strong dependence on the gap-to-diameter ratio. As the gap-to-diameter ratio increases, the critical rotational speed approaches values expected to suppress vortex formation for a single rotating cylinder, indicating that the wakes of the cylinder pair have more interaction for small gap-to-diameter ratios. At sufficiently high rotational speeds the streamlines around the cylinder pair resemble a doublet potential flow. The experiments were inspired by the computations performed by Andy Chan and Antony Jameson at Stanford University.

  4. Advances in Rotational Seismic Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Pierson, Robert [Applied Technology Associates, Albuquerque, NM (United States); Laughlin, Darren [Applied Technology Associates, Albuquerque, NM (United States); Brune, Robert [Applied Technology Associates, Albuquerque, NM (United States)

    2016-10-19

    Rotational motion is increasingly understood to be a significant part of seismic wave motion. Rotations can be important in earthquake strong motion and in Induced Seismicity Monitoring. Rotational seismic data can also enable shear selectivity and improve wavefield sampling for vertical geophones in 3D surveys, among other applications. However, sensor technology has been a limiting factor to date. The US Department of Energy (DOE) and Applied Technology Associates (ATA) are funding a multi-year project that is now entering Phase 2 to develop and deploy a new generation of rotational sensors for validation of rotational seismic applications. Initial focus is on induced seismicity monitoring, particularly for Enhanced Geothermal Systems (EGS) with fracturing. The sensors employ Magnetohydrodynamic (MHD) principles with broadband response, improved noise floors, robustness, and repeatability. This paper presents a summary of Phase 1 results and Phase 2 status.

  5. Rotational superradiance in fluid laboratories

    CERN Document Server

    Cardoso, Vitor; Richartz, Mauricio; Weinfurtner, Silke

    2016-01-01

    Rotational superradiance has been predicted theoretically decades ago, and is the chief responsible for a number of important effects and phenomenology in black hole physics. However, rotational superradiance has never been observed experimentally. Here, with the aim of probing superradiance in the lab, we investigate the behaviour of sound and surface waves in fluids resting in a circular basin at the center of which a rotating cylinder is placed. We show that with a suitable choice for the material of the cylinder, surface and sound waves are amplified. By confining the superradiant modes near the rotating cylinder, an instability sets in. Our findings are experimentally testable in existing fluid laboratories and hence offer experimental exploration and comparison of dynamical instabilities arising from rapidly rotating boundary layers in astrophysical as well as in fluid dynamical systems.

  6. Magnetospheric structure of rotation powered pulsars

    Energy Technology Data Exchange (ETDEWEB)

    Arons, J. (California Univ., Berkeley, CA (USA) California Univ., Livermore, CA (USA). Inst. of Geophysics and Planetary Physics)

    1991-01-07

    I survey recent theoretical work on the structure of the magnetospheres of rotation powered pulsars, within the observational constraints set by their observed spindown, their ability to power synchrotron nebulae and their ability to produce beamed collective radio emission, while putting only a small fraction of their energy into incoherent X- and gamma radiation. I find no single theory has yet given a consistent description of the magnetosphere, but I conclude that models based on a dense outflow of pairs from the polar caps, permeated by a lower density flow of heavy ions, are the most promising avenue for future research. 106 refs., 4 figs., 2 tabs.

  7. Wind tunnel tests of stratospheric airship counter rotating propellers

    Directory of Open Access Journals (Sweden)

    Yaxi Chen

    2015-01-01

    Full Text Available Aerodynamic performance of the high-altitude propeller, especially the counter rotation effects, is experimentally studied. Influences of different configurations on a stratospheric airship, included 2-blade counter-rotating propeller (CRP, dual 2-blade single rotation propellers (SRPs and 4-blade SRP, are also indicated. This research indicates that the effect of counter rotation can greatly improve the efficiency. It shows that the CRP configuration results in a higher efficiency than the dual 2-blade SRPs configuration or 4-blade SRP configuration under the same advance ratio, and the CRP configuration also gains the highest efficiency whether under the situation of providing the same trust or absorbing the same power. It concludes that, for a stratospheric airship, the CRP configuration is better than the multiple SRPs configuration or a multi-blade SRP one.

  8. The Størmer problem for an aligned rotator

    Science.gov (United States)

    Epp, V.; Pervukhina, O. N.

    2018-03-01

    The effective potential energy of the particles in the field of rotating uniformly magnetized celestial body is investigated. The axis of rotation coincides with the axis of the magnetic field. Electromagnetic field of the body is composed of a dipole magnetic and quadrupole electric fields. The geometry of the trapping regions is studied as a function of the magnetic field magnitude and the rotation speed of the body. Examples of the potential energy topology for different values of these parameters are given. The main difference from the classical Størmer problem is that the single toroidal trapping region predicted by Størmer is divided into equatorial and off-equatorial trapping regions. Applicability of the idealized model of a rotating uniformly magnetized sphere with a vacuum magnetosphere to real celestial bodies is discussed.

  9. Magnetostrophic Rotating Magnetoconvection

    Science.gov (United States)

    King, Eric; Aurnou, Jonathan

    2016-11-01

    Planetary magnetic fields are generated by turbulent convection within their vast interior liquid metal cores. Although direct observation is not possible, this liquid metal circulation is thought to be dominated by the controlling influences of Coriolis and Lorentz forces. Theory famously predicts that local-scale convection naturally settles into the so-called magnetostrophic state, where the Coriolis and Lorentz forces partially cancel, and convection is optimally efficient. To date, no laboratory experiments have reached the magnetostrophic regime in turbulent liquid metal convection. Furthermore, computational dynamo simulations have as yet failed to produce a globally magnetostrophic dynamo, which has led some to question the existence of the magnetostrophic state. Here, we present results from the first turbulent magnetostrophic rotating magnetoconvection experiments using the liquid metal gallium. We find that turbulent convection in the magnetostrophic regime is, in fact, maximally efficient. The experimental results clarify these previously disparate results, suggesting that the fluid dynamics saturate in magnetostrophic balance within turbulent liquid metal, planetary cores. The authors thank the NSF Geophysics Program for financial support.

  10. Rotating quantum Gaussian packets

    International Nuclear Information System (INIS)

    Dodonov, V V

    2015-01-01

    We study two-dimensional quantum Gaussian packets with a fixed value of mean angular momentum. This value is the sum of two independent parts: the ‘external’ momentum related to the motion of the packet center and the ‘internal’ momentum due to quantum fluctuations. The packets minimizing the mean energy of an isotropic oscillator with the fixed mean angular momentum are found. They exist for ‘co-rotating’ external and internal motions, and they have nonzero correlation coefficients between coordinates and momenta, together with some (moderate) amount of quadrature squeezing. Variances of angular momentum and energy are calculated, too. Differences in the behavior of ‘co-rotating’ and ‘anti-rotating’ packets are shown. The time evolution of rotating Gaussian packets is analyzed, including the cases of a charge in a homogeneous magnetic field and a free particle. In the latter case, the effect of initial shrinking of packets with big enough coordinate-momentum correlation coefficients (followed by the well known expansion) is discovered. This happens due to a competition of ‘focusing’ and ‘de-focusing’ in the orthogonal directions. (paper)

  11. Rotational Twin Paradox

    Science.gov (United States)

    Smarandache, Florentin

    2012-10-01

    Two twins settle on a massive spherical planet at a train station S. Let's consider that each twin has an accompanying clock, and the two clocks are synchronized. One twin T1 remains in the train station, while the other twin T2 travels at a uniform high speed with the train around the planet (on the big circle of the planet) until he gets back to the same train station S. Assume the planet is not rotating. Since the planet is massive, we can consider that on a very small part on its surface the train rail road is linear, so the train is in a linear uniform motion. The larger is the planet's radius the more the rail road approaches a linear trajectory. Because the GPS clocks are alleged to be built on the Theory of Relativity, one can consider the twin T2 train's circular trajectory alike the satellite's orbit. In addition, the gravitation is the same for the reference frames of T1 and T2. Each twin sees the other twin as traveling, therefore each twin finds the other one has aged slower than him. Thus herein we have a relativistic symmetry. When T2 returns to train station S, he finds out that he is younger than T1 (therefore asymmetry). Thus, one gets a contradiction between symmetry and asymmetry.

  12. Wave-driven rotation and mass separation in rotating magnetic mirrors

    Science.gov (United States)

    Fetterman, Abraham J.

    Axisymmetric mirrors are attractive for fusion because of their simplicity, high plasma pressure at a given magnetic pressure, and steady state operation. Their subclass, rotating mirrors, are particularly interesting because they have increased parallel confinement, magnetohydrodynamic stability, and a natural heating mechanism. This thesis finds and explores an unusual effect in supersonically rotating plasmas: particles are diffused by waves in both potential energy and kinetic energy. Extending the alpha channeling concept to rotating plasmas, the alpha particles may be removed at low energy through the loss cone, and the energy lost may be transferred to the radial electric field. This eliminates the need for electrodes in the mirror throat, which have presented serious technical issues in past rotating plasma devices. A high azimuthal mode number perturbation on the magnetic field is a particularly simple way to achieve the latter effect. In the rotating frame, this perturbation is seen as a wave near the alpha particle cyclotron harmonic, and can break the azimuthal symmetry and magnetic moment conservation without changing the particles total energy. The particle may exit if it reduces its kinetic energy and becomes more trapped if it gains kinetic energy, leading to a steady state current that maintains the field. Simulations of single particles in rotating mirrors show that a stationary wave can extract enough energy from alpha particles for a reactor to be self-sustaining. In the same way, rotation can be produced in non-fusion plasmas. Waves are identified to produce rotation in plasma centrifuges, which separate isotopes based on their mass difference. Finally, a new high throughput mass filter which is well suited to separating nuclear waste is presented. The new filter, the magnetic centrifugal mass filter (MCMF), has well confined output streams and less potential for nuclear proliferation than competing technologies. To assess the usefulness of the

  13. Toroidal rotation studies in KSTAR

    Science.gov (United States)

    Lee, S. G.; Lee, H. H.; Yoo, J. W.; Kim, Y. S.; Ko, W. H.; Terzolo, L.; Bitter, M.; Hill, K.; KSTAR Team

    2014-10-01

    Investigation of the toroidal rotation is one of the most important topics for the magnetically confined fusion plasma researches since it is essential for the stabilization of resistive wall modes and its shear plays an important role to improve plasma confinement by suppressing turbulent transport. The most advantage of KSTAR tokamak for toroidal rotation studies is that it equips two main diagnostics including the high-resolution X-ray imaging crystal spectrometer (XICS) and charge exchange spectroscopy (CES). Simultaneous core toroidal rotation and ion temperature measurements of different impurity species from the XICS and CES have shown in reasonable agreement with various plasma discharges in KSTAR. It has been observed that the toroidal rotation in KSTAR is faster than that of other tokamak devices with similar machine size and momentum input. This may due to an intrinsically low toroidal field ripple and error field of the KSTAR device. A strong braking of the toroidal rotation by the n = 1 non-resonant magnetic perturbations (NRMPs) also indicates these low toroidal field ripple and error field. Recently, it has been found that n = 2 NRMPs can also damp the toroidal rotation in KSTAR. The detail toroidal rotation studies will be presented. Work supported by the Korea Ministry of Science, ICT and Future Planning under the KSTAR project.

  14. Rotational discontinuities in anisotropic plasmas

    International Nuclear Information System (INIS)

    Omidi, N.

    1992-01-01

    The kinetic structure of rotational discontinuities (RDs) in anisotropic plasmas with T perpendicular /T parallel > 1 is investigated by using a one-dimensional electromagnetic hybrid code. To form the RD, a new approach is used where the plasma is injected from one boundary and reflected from the other, resulting in the generation of a traveling fast shock and an RD. Unlike the previously used methods, no a priori assumptions are made regarding the initial structure (i.e. width or sense of rotation) of the rotational discontinuity. The results show that across the RD both the magnetic field strength and direction, as well as the plasma density change. Given that such a change can also be associated with an intermediate shock, the Rankine-Hugoniot relations are used to confirm that the observed structures are indeed RDs. It is found that the thickness of RDs is a few ion inertial lengths and is independent of the rotation angle. Also, the preferred sense of rotation is in the electron sense; however, RDs with a rotation angle larger than 180 degree are found to be unstable, changing their rotation to a stable ion sense

  15. Rotating relativistic neutron stars

    Energy Technology Data Exchange (ETDEWEB)

    Weber, F.; Glendenning, N.K.

    1991-07-21

    Models of rotating neutron stars are constructed in the framework of Einstein's theory of general relativity. For this purpose a refined version of Hartle's method is applied. The properties of these objects, e.g. gravitational mass, equatorial and polar radius, eccentricity, red- and blueshift, quadrupole moment, are investigated for Kepler frequencies of 4000 s{sup {minus}1} {le} {Omega}{sub K} {le} 9000 s{sup {minus}1}. Therefore a self-consistency problem inherent in the determination of {Omega}{sub K} must be solved. The investigation is based on neutron star matter equations of state derived from the relativistic Martin-Schwinger hierarch of coupled Green's functions. By means of introducing the Hartree, Hartree-Fock, and ladder ({Lambda}) approximations, models of the equation of state derived. A special feature of the latter approximation scheme is the inclusion of dynamical two-particle correlations. These have been calculated from the relativistic T-matrix applying both the HEA and Bonn meson-exchange potentials of the nucleon-nucleon force. The nuclear forces of the former two treatments are those of the standard scalar-vector-isovector model of quantum hadron dynamics, with parameters adjusted to the nuclear matter data. An important aspect of this work consists in testing the compatibility of different competing models of the nuclear equation of state with data on pulsar periods. By this the fundamental problem of nuclear physics concerning the behavior of the equation of state at supernuclear densities can be treated.

  16. Counter-Rotatable Fan Gas Turbine Engine with Axial Flow Positive Displacement Worm Gas Generator

    Science.gov (United States)

    Giffin, Rollin George (Inventor); Murrow, Kurt David (Inventor); Fakunle, Oladapo (Inventor)

    2014-01-01

    A counter-rotatable fan turbine engine includes a counter-rotatable fan section, a worm gas generator, and a low pressure turbine to power the counter-rotatable fan section. The low pressure turbine maybe counter-rotatable or have a single direction of rotation in which case it powers the counter-rotatable fan section through a gearbox. The gas generator has inner and outer bodies having offset inner and outer axes extending through first, second, and third sections of a core assembly. At least one of the bodies is rotatable about its axis. The inner and outer bodies have intermeshed inner and outer helical blades wound about the inner and outer axes and extending radially outwardly and inwardly respectively. The helical blades have first, second, and third twist slopes in the first, second, and third sections respectively. A combustor section extends through at least a portion of the second section.

  17. Single curved fiber sedimentation under gravity

    Science.gov (United States)

    Xiaoying Rong; Dewei Qi; Junyong Zhu

    2005-01-01

    Dynamics of single curved fiber sedimentation under the gravity are simulated by using lattice Boltzmann method. The results of migration and rotation of the curved fiber at different Reynolds numbers are reported. The results show that the rotation and migration processes are sensitive to the curvature of the fiber.

  18. Rotational spectra and molecular structure

    CERN Document Server

    Wollrab, James E

    1967-01-01

    Physical Chemistry, A Series of Monographs: Rotational Spectra and Molecular Structure covers the energy levels and rotational transitions. This book is divided into nine chapters that evaluate the rigid asymmetric top molecules and the nuclear spin statistics for asymmetric tops. Some of the topics covered in the book are the asymmetric rotor functions; rotational transition intensities; classes of molecules; nuclear spin statistics for linear molecules and symmetric tops; and classical appearance of centrifugal and coriolis forces. Other chapters deal with the energy levels and effects of ce

  19. On the Rotating and Oscillating strings in $(AdS_3\\times S^3)_{\\varkappa}$

    CERN Document Server

    Banerjee, Aritra

    2014-01-01

    We study rigidly rotating strings in the $\\varkappa$-deformed $AdS_3 \\times S^3$ background. We find out two classes of solutions corresponding to the giant magnon and single spike solutions of the string rotating is two $S^2_{\\varkappa}$ subspace of rotations reduced along two different isometries. We verify that the dispersion relations reduce to the well known relation in the $\\varkappa\\rightarrow 0$ limit. We further study some oscillating string solutions in the $S^3_{\\varkappa}$ subspace.

  20. Single well techniques

    International Nuclear Information System (INIS)

    Drost, W.

    1983-01-01

    The single well technique method includes measurement of parameters of groundwater flow in saturated rock. For determination of filtration velocity the dilution of radioactive tracer is measured, for direction logging the collimeter is rotated in the probe linked with the compass. The limiting factor for measurement of high filtration velocities is the occurrence of turbulent flow. The single well technique is used in civil engineering projects, water works and subsurface drainage of liquid waste from disposal sites. The radioactive tracer method for logging the vertical fluid movement in bore-holes is broadly used in groundwater survey and exploitation. (author)

  1. Spontaneous Rotational Inversion in Phycomyces

    KAUST Repository

    Goriely, Alain

    2011-03-01

    The filamentary fungus Phycomyces blakesleeanus undergoes a series of remarkable transitions during aerial growth. During what is known as the stagea IV growth phase, the fungus extends while rotating in a counterclockwise manner when viewed from above (stagea IVa) and then, while continuing to grow, spontaneously reverses to a clockwise rotation (stagea IVb). This phase lasts for 24-48Ah and is sometimes followed by yet another reversal (stageAIVc) before the overall growth ends. Here, we propose a continuum mechanical model of this entire process using nonlinear, anisotropic, elasticity and show how helical anisotropy associated with the cell wall structure can induce spontaneous rotation and, under appropriate circumstances, the observed reversal of rotational handedness. © 2011 American Physical Society.

  2. An Exercise in Rotational Motion.

    Science.gov (United States)

    Mahoney, Brother James

    1980-01-01

    Describes an advanced high school physics experiment demonstrating rotational kinematics and dynamics, using simple equipment such as empty coffee cans, inclined planes, meter sticks, and a large 10-second demonstration timer. (CS)

  3. MAX-DOAS measurements of HONO slant column densities during the MAD-CAT campaign: inter-comparison, sensitivity studies on spectral analysis settings, and error budget

    Science.gov (United States)

    Wang, Yang; Beirle, Steffen; Hendrick, Francois; Hilboll, Andreas; Jin, Junli; Kyuberis, Aleksandra A.; Lampel, Johannes; Li, Ang; Luo, Yuhan; Lodi, Lorenzo; Ma, Jianzhong; Navarro, Monica; Ortega, Ivan; Peters, Enno; Polyansky, Oleg L.; Remmers, Julia; Richter, Andreas; Puentedura, Olga; Van Roozendael, Michel; Seyler, André; Tennyson, Jonathan; Volkamer, Rainer; Xie, Pinhua; Zobov, Nikolai F.; Wagner, Thomas

    2017-10-01

    In order to promote the development of the passive DOAS technique the Multi Axis DOAS - Comparison campaign for Aerosols and Trace gases (MAD-CAT) was held at the Max Planck Institute for Chemistry in Mainz, Germany, from June to October 2013. Here, we systematically compare the differential slant column densities (dSCDs) of nitrous acid (HONO) derived from measurements of seven different instruments. We also compare the tropospheric difference of SCDs (delta SCD) of HONO, namely the difference of the SCDs for the non-zenith observations and the zenith observation of the same elevation sequence. Different research groups analysed the spectra from their own instruments using their individual fit software. All the fit errors of HONO dSCDs from the instruments with cooled large-size detectors are mostly in the range of 0.1 to 0.3 × 1015 molecules cm-2 for an integration time of 1 min. The fit error for the mini MAX-DOAS is around 0.7 × 1015 molecules cm-2. Although the HONO delta SCDs are normally smaller than 6 × 1015 molecules cm-2, consistent time series of HONO delta SCDs are retrieved from the measurements of different instruments. Both fits with a sequential Fraunhofer reference spectrum (FRS) and a daily noon FRS lead to similar consistency. Apart from the mini-MAX-DOAS, the systematic absolute differences of HONO delta SCDs between the instruments are smaller than 0.63 × 1015 molecules cm-2. The correlation coefficients are higher than 0.7 and the slopes of linear regressions deviate from unity by less than 16 % for the elevation angle of 1°. The correlations decrease with an increase in elevation angle. All the participants also analysed synthetic spectra using the same baseline DOAS settings to evaluate the systematic errors of HONO results from their respective fit programs. In general the errors are smaller than 0.3 × 1015 molecules cm-2, which is about half of the systematic difference between the real measurements.The differences of HONO delta SCDs

  4. Rotating Shadowband Spectroradiometer (RSS) Handbook

    Energy Technology Data Exchange (ETDEWEB)

    Kiedron, P; Schlemmer, J; Klassen, M

    2005-01-01

    The rotating shawdowband spectroradiometer (RSS) implements the same automated shadowbanding technique used by the multifilter rotating shadowband radiometer (MFRSR), and so it too provides spectrally-resolved, direct-normal, diffuse-horizontal, and total-horizontal irradiances, and can be calibrated in situ via Langley regression. The irradiance spectra are measured simultaneously at all spectral elements (pixels) in 360-nm to 1050-nm range.

  5. Control strategy for permanent magnet synchronous motor with contra-rotating rotors under unbalanced loads condition

    DEFF Research Database (Denmark)

    Cheng, Shuangyin; Luo, Derong; Huang, Shoudao

    2015-01-01

    This study presents an investigation into the control of an axial-flux permanent magnet synchronous machine (PMSM) with contra-rotating rotors fed by a single inverter, which corresponds to two PMSM connected in series. In this study, the mathematic model of the PMSM with contra-rotating rotors...

  6. A high-precision mechanical absolute-rotation sensor.

    Science.gov (United States)

    Venkateswara, Krishna; Hagedorn, Charles A; Turner, Matthew D; Arp, Trevor; Gundlach, Jens H

    2014-01-01

    We have developed a mechanical absolute-rotation sensor capable of resolving ground rotation angle of less than 1 nrad/√Hz above 30 mHz and 0.2 nrad/√Hz above 100 mHz about a single horizontal axis. The device consists of a meter-scale beam balance, suspended by a pair of flexures, with a resonance frequency of 10.8 mHz. The center of mass is located 3 μm above the pivot, giving an excellent horizontal displacement rejection of better than 3 × 10(-5) rad/m. The angle of the beam is read out optically using a high-sensitivity autocollimator. We have also built a tiltmeter with better than 1 nrad/√Hz sensitivity above 30 mHz. Co-located measurements using the two instruments allowed us to distinguish between background rotation signal at low frequencies and intrinsic instrument noise. The rotation sensor is useful for rotational seismology and for rejecting background rotation signal from seismometers in experiments demanding high levels of seismic isolation, such as Advanced Laser Interferometer Gravitational-wave Observatory.

  7. Practice of the rotation of assemblies during refuelling in NPP of Paks

    International Nuclear Information System (INIS)

    Szecsenyi, Z.

    1998-01-01

    Few years ago it turned out that two kk distributions could differ from each other if the kk is calculated using pin-wise burn-up distribution and the pin-wise burn-up distribution is very slanted or using averaged burn-up distribution. In that case when the former manner calculated value of kkmax is higher then the other one, the value of kkmax can be decreased with the rotation of the assembly. As a consequence of the development of computer technique an opportunity presents itself for the practical application of pin-wise burn-up calculation. At the outset the pin-wise burn-up calculation was made for that assembly, where the reactor-physics parameters were near the safety values. Nowadays the further development of the hardware and software devices present opportunity for the full-scope following of the pin-wise burn-up, in all assemblies. In this paper is presented a short historical review of the above mentioned events, practical adaption of the pin-wise burn-up following and display of some used reactor-physics codes.(Author)

  8. Rotating crystal pulse shaper for use on a pulsed neutron source

    International Nuclear Information System (INIS)

    Carpenter, J.M.; Carlile, C.J.

    1983-01-01

    A pulse shortening device is described for use on pulsed thermal neutron sources. The device employs rotating single crystals and has applications in the design of high resolution cold neutron spectrometers

  9. Refueling system with small diameter rotatable plugs

    International Nuclear Information System (INIS)

    Ritz, W.C.

    1987-01-01

    This patent describes a liquid-metal fastbreeder nuclear reactor comprising a reactor pressure vessel and closure head therefor, a reactor core barrel disposed within the reactor vessel and enclosing a reactor core having therein a large number of closely spaced fuel assemblies, and the reactor core barrel and the reactor core having an approximately concentric circular cross-sectional configuration with a geometric center in predetermined location within the reactor vessel. The improved refueling system described here comprises: a large controllably rotatable plug means comprising the substantial portion of the closure head, a reactor upper internals structure mounted from the large rotatable plug means. The large rotatable plug means has an approximately circular configuration which approximates the cross-sectional configuration of the reactor core barrel with a center of rotation positioned a first predetermined distance from the geometric center of the reactor core barrel so that the large rotatable plug means rotates eccentrically with respect to the reactor core barrel; a small controllably rotatable plug means affixed to the large rotatable plug means and rotatable with respect thereto. The small rotatable plug means has a center of rotation which is offset a second predetermined distance from the rotational center of the large rotatable plug means so that the small rotatable plug means rotates eccentrically with respect to the large rotatable plug means

  10. Rotational memory effect of a multimode fiber

    NARCIS (Netherlands)

    Amitonova, Lyubov V.; Mosk, Allard P.; Pinkse, Pepijn W. H.

    2015-01-01

    We demonstrate the rotational memory effect in a multimode fiber. Rotating the incident wavefront around the fiber core axis leads to a rotation of the resulting pattern of the fiber output without significant changes in the resulting speckle pattern. The rotational memory effect can be exploited

  11. Tokamak rotation and charge exchange

    International Nuclear Information System (INIS)

    Hazeltine, R.D.; Rowan, W.L.; Solano, E.R.; Valanju, P.M.

    1991-01-01

    In the absence of momentum input, tokamak toroidal rotation rates are typically small - no larger in particular than poloidal rotation - even when the radial electric field is strong, as near the plasma edge. This circumstance, contradicting conventional neoclassical theory, is commonly attributed to the rotation damping effect of charge exchange, although a detailed comparison between charge-exchange damping theory and experiment is apparently unavailable. Such a comparison is attempted here in the context of recent TEXT experiments, which compare rotation rates, both poloidal and toroidal, in helium and hydrogen discharges. The helium discharges provide useful data because they are nearly free of ion-neutral charge exchange; they have been found to rotate toroidally in reasonable agreement with neoclassical predictions. The hydrogen experiments show much smaller toroidal motion as usual. The theoretical calculation uses the full charge-exchange operator and assumes plateau collisionality, roughly consistent with the experimental conditions. The authors calculate the ion flow as a function of v cx /v c , where v cx is the charge exchange rate and v c the Coulomb collision frequency. The results are in reasonable accord with the observations. 1 ref

  12. A technique to capture, analyze, and quantify anterior teeth rotations for application in court cases involving tooth marks.

    Science.gov (United States)

    Bernitz, Herman; van Heerden, Willie F P; Solheim, Tore; Owen, Johanna H

    2006-05-01

    Anterior teeth within the human dentition have a specific numerical rotation value. Bite marks show an array of angled indentations, abrasions, microlacerations, and contusions. These marks generally represent the incisal surfaces of the suspect's dentition reflecting the rotation values of the teeth in the dental arch. This study described a method for capturing and analyzing anterior dental rotations. The rotations of individual anterior teeth within the study population were categorized as common, uncommon, and very uncommon according to Allen's classification. In the absence of a large number of incisal patterns present in a bite mark, a single but heavily weighted tooth rotation could be of equal discriminatory potential to several common rotation values. No prevalence studies quantifying individual tooth rotations are available. The measurement of each individual tooth rotation together with its individual discrimination potential will enhance the evaluation of the concordant features observed in bite marks.

  13. Rotating concentric homogeneous turbulence centrifuge

    International Nuclear Information System (INIS)

    Leith, W.C.

    1976-01-01

    A gas centrifuge and a method are described for the separation of isotopic gaseous mixtures, particularly for the enrichment of uranium by the evaporative, concurrent-flow and countercurrent-flow principles using Taylor circular Couette motion. Gaseous isotopes either alone or mixed with a carrier gas, more particularly uranium isotopes in mixture with uranium hexafluoride carrier gas, are fed to a rotor assembly of a gas centrifuge which comprises two concentric cylinders which may be rotated at the same or at different angular velocities and in the same or opposite directions to create centrifugal forces sufficient to diffuse the heavier fraction of the gas mixture to the periphery of the assembly and the lighter fraction towards the axial portion of the assembly. The rotor comprises an inner, perforate, rotatable cylinder and an outer, continuous, smooth-walled, rotatable cylinder concentric with the inner cylinder and defining an annulus therebetween. 14 claims, 5 figures

  14. Instabilities in coaxial rotating jets

    Science.gov (United States)

    Ivanic, Tanja; Foucault, Eric; Pecheux, Jean; Gilard, Virginie

    2000-12-01

    The aim of this study is the characterization of the cylindrical mixing layer resulting from the interaction of two coaxial swirling jets. The experimental part of this study was performed in a cylindrical water tunnel, permitting an independent rotation of two coaxial jets. The rotations are generated by means of 2×36 blades localized in two swirling chambers. As expected, the evolution of the main instability modes presents certain differences compared to the plane-mixing-layer case. Experimental results obtained by tomography showed the existence of vortex rings and streamwise vortex pairs in the near field region. This method also permitted the observation of the evolution and interaction of different modes. PIV velocity measurements realized in the meridian plans and the plans perpendicular to the jet axis show that rotation distorts the typical top-hat axial velocity profile. The transition of the axial velocity profile from jet-like into wake-like is also observed.

  15. Rotation, activity, and lithium abundance in cool binary stars

    Science.gov (United States)

    Strassmeier, K. G.; Weber, M.; Granzer, T.; Järvinen, S.

    2012-10-01

    We have used two robotic telescopes to obtain time-series high-resolution optical echelle spectroscopy and V I and/or by photometry for a sample of 60 active stars, mostly binaries. Orbital solutions are presented for 26 double-lined systems and for 19 single-lined systems, seven of them for the first time but all of them with unprecedented phase coverage and accuracy. Eighteen systems turned out to be single stars. The total of 6609 {R=55 000} échelle spectra are also used to systematically determine effective temperatures, gravities, metallicities, rotational velocities, lithium abundances and absolute Hα-core fluxes as a function of time. The photometry is used to infer unspotted brightness, {V-I} and/or b-y colors, spot-induced brightness amplitudes and precise rotation periods. An extra 22 radial-velocity standard stars were monitored throughout the science observations and yield a new barycentric zero point for our STELLA/SES robotic system. Our data are complemented by literature data and are used to determine rotation-temperature-activity relations for active binary components. We also relate lithium abundance to rotation and surface temperature. We find that 74 % of all known rapidly-rotating active binary stars are synchronized and in circular orbits but 26 % (61 systems) are rotating asynchronously of which half have {P_rot>P_orb} and {e>0}. Because rotational synchronization is predicted to occur before orbital circularization active binaries should undergo an extra spin-down besides tidal dissipation. We suspect this to be due to a magnetically channeled wind with its subsequent braking torque. We find a steep increase of rotation period with decreasing effective temperature for active stars, P_rot ∝ T_eff-7, for both single and binaries, main sequence and evolved. For inactive, single giants with {P_rot>100} d, the relation is much weaker, {P_rot ∝ T_eff-1.12}. Our data also indicate a period-activity relation for Hα of the form {R_Hα ∝ P

  16. Laser Oscillator Incorporating a Wedged Polarization Rotator and a Porro Prism as Cavity Mirror

    Science.gov (United States)

    Li, Steven

    2011-01-01

    A laser cavity was designed and implemented by using a wedged polarization rotator and a Porro prism in order to reduce the parts count, and to improve the laser reliability. In this invention, a z-cut quartz polarization rotator is used to compensate the wavelength retardance introduced by the Porro prism. The polarization rotator rotates the polarization of the linear polarized beam with a designed angle that is independent of the orientation of the rotator. This unique property was used to combine the retardance compensation and a Risley prism to a single optical component: a wedged polarization rotator. This greatly simplifies the laser alignment procedure and reduces the number of the laser optical components.

  17. MAX-DOAS measurements of HONO slant column densities during the MAD-CAT campaign: inter-comparison, sensitivity studies on spectral analysis settings, and error budget

    Directory of Open Access Journals (Sweden)

    Y. Wang

    2017-10-01

    Full Text Available In order to promote the development of the passive DOAS technique the Multi Axis DOAS – Comparison campaign for Aerosols and Trace gases (MAD-CAT was held at the Max Planck Institute for Chemistry in Mainz, Germany, from June to October 2013. Here, we systematically compare the differential slant column densities (dSCDs of nitrous acid (HONO derived from measurements of seven different instruments. We also compare the tropospheric difference of SCDs (delta SCD of HONO, namely the difference of the SCDs for the non-zenith observations and the zenith observation of the same elevation sequence. Different research groups analysed the spectra from their own instruments using their individual fit software. All the fit errors of HONO dSCDs from the instruments with cooled large-size detectors are mostly in the range of 0.1 to 0.3  ×  1015 molecules cm−2 for an integration time of 1 min. The fit error for the mini MAX-DOAS is around 0.7  ×  1015 molecules cm−2. Although the HONO delta SCDs are normally smaller than 6  ×  1015 molecules cm−2, consistent time series of HONO delta SCDs are retrieved from the measurements of different instruments. Both fits with a sequential Fraunhofer reference spectrum (FRS and a daily noon FRS lead to similar consistency. Apart from the mini-MAX-DOAS, the systematic absolute differences of HONO delta SCDs between the instruments are smaller than 0.63  ×  1015 molecules cm−2. The correlation coefficients are higher than 0.7 and the slopes of linear regressions deviate from unity by less than 16 % for the elevation angle of 1°. The correlations decrease with an increase in elevation angle. All the participants also analysed synthetic spectra using the same baseline DOAS settings to evaluate the systematic errors of HONO results from their respective fit programs. In general the errors are smaller than 0.3  ×  1015 molecules cm−2, which is

  18. Rotated balance in humans due to repetitive rotational movement

    Science.gov (United States)

    Zakynthinaki, M. S.; Madera Milla, J.; López Diaz De Durana, A.; Cordente Martínez, C. A.; Rodríguez Romo, G.; Sillero Quintana, M.; Sampedro Molinuevo, J.

    2010-03-01

    We show how asymmetries in the movement patterns during the process of regaining balance after perturbation from quiet stance can be modeled by a set of coupled vector fields for the derivative with respect to time of the angles between the resultant ground reaction forces and the vertical in the anteroposterior and mediolateral directions. In our model, which is an adaption of the model of Stirling and Zakynthinaki (2004), the critical curve, defining the set of maximum angles one can lean to and still correct to regain balance, can be rotated and skewed so as to model the effects of a repetitive training of a rotational movement pattern. For the purposes of our study a rotation and a skew matrix is applied to the critical curve of the model. We present here a linear stability analysis of the modified model, as well as a fit of the model to experimental data of two characteristic "asymmetric" elite athletes and to a "symmetric" elite athlete for comparison. The new adapted model has many uses not just in sport but also in rehabilitation, as many work place injuries are caused by excessive repetition of unaligned and rotational movement patterns.

  19. Strongly interacting matter under rotation

    Science.gov (United States)

    Jiang, Yin; Lin, Zi-Wei; Huang, Xu-Guang; Liao, Jinfeng

    2018-02-01

    The vorticity-driven effects are systematically studied in various aspects. With AMPT the distributions of vorticity has been investigated in heavy ion collisions with different collision parameters. Taking the rotational polarization effect into account a generic condensate suppression mechanism is discussed and quantitatively studied with NJL model. And in chiral restored phase the chiral vortical effects would generate a new collective mode, i.e. the chiral vortical wave. Using the rotating quark-gluon plasma in heavy ion collisions as a concrete example, we show the formation of induced flavor quadrupole in QGP and estimate the elliptic flow splitting effect for Λ baryons.

  20. Mach's principle and rotating universes

    International Nuclear Information System (INIS)

    King, D.H.

    1990-01-01

    It is shown that the Bianchi 9 model universe satisfies the Mach principle. These closed rotating universes were previously thought to be counter-examples to the principle. The Mach principle is satisfied because the angular momentum of the rotating matter is compensated by the effective angular momentum of gravitational waves. A new formulation of the Mach principle is given that is based on the field theory interpretation of general relativity. Every closed universe with 3-sphere topology is shown to satisfy this formulation of the Mach principle. It is shown that the total angular momentum of the matter and gravitational waves in a closed 3-sphere topology universe is zero

  1. Energy Transfer in Rotating Turbulence

    Science.gov (United States)

    Cambon, Claude; Mansour, Nagi N.; Godeferd, Fabien S.; Rai, Man Mohan (Technical Monitor)

    1995-01-01

    The influence or rotation on the spectral energy transfer of homogeneous turbulence is investigated in this paper. Given the fact that linear dynamics, e.g. the inertial waves regime tackled in an RDT (Rapid Distortion Theory) fashion, cannot Affect st homogeneous isotropic turbulent flow, the study of nonlinear dynamics is of prime importance in the case of rotating flows. Previous theoretical (including both weakly nonlinear and EDQNM theories), experimental and DNS (Direct Numerical Simulation) results are gathered here and compared in order to give a self-consistent picture of the nonlinear effects of rotation on tile turbulence. The inhibition of the energy cascade, which is linked to a reduction of the dissipation rate, is shown to be related to a damping due to rotation of the energy transfer. A model for this effect is quantified by a model equation for the derivative-skewness factor, which only involves a micro-Rossby number Ro(sup omega) = omega'/(2(OMEGA))-ratio of rms vorticity and background vorticity as the relevant rotation parameter, in accordance with DNS and EDQNM results fit addition, anisotropy is shown also to develop through nonlinear interactions modified by rotation, in an intermediate range of Rossby numbers (Ro(omega) = (omega)' and Ro(omega)w greater than 1), which is characterized by a marco-Rossby number Ro(sup L) less than 1 and Ro(omega) greater than 1 which is characterized by a macro-Rossby number based on an integral lengthscale L and the micro-Rossby number previously defined. This anisotropy is mainly an angular drain of spectral energy which tends to concentrate energy in tile wave-plane normal to the rotation axis, which is exactly both the slow and the two-dimensional manifold. In Addition, a polarization of the energy distribution in this slow 2D manifold enhances horizontal (normal to the rotation axis) velocity components, and underlies the anisotropic structure of the integral lengthscales. Finally is demonstrated the

  2. Strongly interacting matter under rotation

    Directory of Open Access Journals (Sweden)

    Jiang Yin

    2018-01-01

    Full Text Available The vorticity-driven effects are systematically studied in various aspects. With AMPT the distributions of vorticity has been investigated in heavy ion collisions with different collision parameters. Taking the rotational polarization effect into account a generic condensate suppression mechanism is discussed and quantitatively studied with NJL model. And in chiral restored phase the chiral vortical effects would generate a new collective mode, i.e. the chiral vortical wave. Using the rotating quark-gluon plasma in heavy ion collisions as a concrete example, we show the formation of induced flavor quadrupole in QGP and estimate the elliptic flow splitting effect for Λ baryons.

  3. External Aerodynamics Simulations in a Rotating Frame of Reference

    Directory of Open Access Journals (Sweden)

    Filomena Cariglino

    2014-01-01

    Full Text Available This paper presents the development of a tool integrated in the UNS3D code, proprietary of Alenia Aermacchi, for the simulation of external aerodynamic flow in a rotating reference frame, with the main objective of predicting propeller-aircraft integration effects. The equations in a rotating frame of reference have been formulated in terms of the absolute velocity components; in this way, the artificial dissipation needed for convergence is lessened, as the Coriolis source term is only introduced in the momentum equation. An Explicit Algebraic Reynolds Stress turbulence model is used. The first assessment of effectiveness of this method is made computing stability derivatives of a NACA 0012 airfoil. Finally, steady Navier-Stokes and Euler simulations of a four-blade single-rotating propeller are presented, demonstrating the efficiency of the chosen approach in terms of computational cost.

  4. High spin rotations of nuclei with the harmonic oscillator potential

    International Nuclear Information System (INIS)

    Cerkaski, M.; Szymanski, Z.

    1978-01-01

    Calculations of the nuclear properties at high angular momentum have been performed recently. They are based on the liquid drop model of a nucleus and/or on the assumption of the single particle shell structure of the nucleonic motion. The calculations are usually complicated and involve long computer codes. In this article we shall discuss general trends in fast rotating nuclei in the approximation of the harmonic oscillator potential. We shall see that using the Bohr Mottelson simplified version of the rigorous solution of Valatin one can perform a rather simple analysis of the rotational bands, structure of the yrast line, moments of inertia etc. in the rotating nucleus. While the precision fit to experimental data in actual nuclei is not the purpose of this paper, one can still hope to reach some general understanding within the model of the simple relations resulting in nuclei at high spin. (author)

  5. A novel method of measuring spatial rotation angle using MEMS tilt sensors

    International Nuclear Information System (INIS)

    Cao, Jian’an; Zhu, Xin; Zhang, Leping; Wu, Hao

    2017-01-01

    This paper presents a novel method of measuring spatial rotation angle with a dual-axis micro-electro-mechanical systems tilt sensor. When the sensor is randomly mounted on the surface of the rotating object, there are three unpredictable and unknown mounting position parameters: α , the sensor’s swing angle on the measuring plane; β , the angle between the rotation axis and the horizontal plane; and γ , the angle between the measuring plane and the rotation axis. Thus, the sensor’s spatial rotation model is established to describe the relationship between the measuring axis, rotation axis, and horizontal plane, and the corresponding analytical equations are derived. Furthermore, to eliminate the deviation caused by the uncertain direction of the rotation axis, an extra perpendicularly mounted, single-axis tilt sensor is combined with the dual-axis tilt sensor, forming a three-axis tilt sensor. Then, by measuring the sensors’ three tilts and solving the model’s equations, the object’s spatial rotation angle is obtained. Finally, experimental results show that the developed tilt sensor is capable of measuring spatial rotation angle in the range of  ±180° with an accuracy of 0.2° if the angle between the rotation axis and the horizontal plane is less than 75°. (paper)

  6. THE RADIO ACTIVITY-ROTATION RELATION OF ULTRACOOL DWARFS

    International Nuclear Information System (INIS)

    McLean, M.; Berger, E.; Reiners, A.

    2012-01-01

    We present a new radio survey of about 100 late-M and L dwarfs undertaken with the Very Large Array. The sample was chosen to explore the role of rotation in the radio activity of ultracool dwarfs. As part of the survey we discovered radio emission from three new objects, 2MASS J 0518113 – 310153 (M6.5), 2MASS J 0952219 – 192431 (M7), and 2MASS J 1314203 + 132001 (M7), and made an additional detection of LP 349-25 (M8). Combining the new sample with results from our previous studies and from the literature, we compile the largest sample to date of ultracool dwarfs with radio observations and measured rotation velocities (167 objects). In the spectral type range M0-M6 we find a radio activity-rotation relation, with saturation at L rad /L bol ≈ 10 –7.5 above vsin i ≈ 5 km s –1 , similar to the relation in Hα and X-rays. However, at spectral types ∼> M7 the ratio of radio to bolometric luminosity increases significantly regardless of rotation velocity, and the scatter in radio luminosity increases. In particular, while the most rapid rotators (vsin i ∼> 20 km s –1 ) exhibit 'super-saturation' in X-rays and Hα, this effect is not seen in the radio. We also find that ultracool dwarfs with vsin i ∼> 20 km s –1 have a higher radio detection fraction by about a factor of three compared to objects with vsin i ∼ –1 . When measured in terms of the Rossby number (Ro), the radio activity-rotation relation follows a single trend and with no apparent saturation from G to L dwarfs and down to Ro ∼ 10 –3 ; in X-rays and Hα there is clear saturation at Ro ∼ rad /R 2 * ) as a function of Ro. The continued role of rotation in the overall level of radio activity and in the fraction of active sources, and the single trend of L rad /L bol and L rad /R 2 * as a function of Ro from G to L dwarfs, indicates that rotation effects are important in regulating the topology or strength of magnetic fields in at least some fully convective dwarfs. The fact that

  7. Single Station System and Method of Locating Lightning Strikes

    Science.gov (United States)

    Medelius, Pedro J. (Inventor); Starr, Stanley O. (Inventor)

    2003-01-01

    An embodiment of the present invention uses a single detection system to approximate a location of lightning strikes. This system is triggered by a broadband RF detector and measures a time until the arrival of a leading edge of the thunder acoustic pulse. This time difference is used to determine a slant range R from the detector to the closest approach of the lightning. The azimuth and elevation are determined by an array of acoustic sensors. The leading edge of the thunder waveform is cross-correlated between the various acoustic sensors in the array to determine the difference in time of arrival, AT. A set of AT S is used to determine the direction of arrival, AZ and EL. The three estimated variables (R, AZ, EL) are used to locate a probable point of the lightning strike.

  8. Rice-ball structures of iron-benzene clusters, Fe{sub 4}-(C{sub 6}H{sub 6}){sub m}, m Less-Than-Or-Slanted-Equal-To 3. A density functional study

    Energy Technology Data Exchange (ETDEWEB)

    Valencia, Israel; Tavizon, Gustavo; Barba-Behrens, Norah [Departamento de Fisica y Quimica Teorica, DEPg. Facultad de Quimica, Universidad Nacional Autonoma de Mexico, C.P. 04510, Mexico D.F. (Mexico); Departamento de Quimica Inorganica, DEPg. Facultad de Quimica, Universidad Nacional Autonoma de Mexico, C.P. 04510, Mexico D.F. (Mexico); Castro, Miguel, E-mail: castro@quetzal.pquim.unam.mx [Departamento de Fisica y Quimica Teorica, DEPg. Facultad de Quimica, Universidad Nacional Autonoma de Mexico, C.P. 04510, Mexico D.F. (Mexico); Departamento de Quimica Inorganica, DEPg. Facultad de Quimica, Universidad Nacional Autonoma de Mexico, C.P. 04510, Mexico D.F. (Mexico)

    2011-11-18

    Graphical abstract: Adsorption of benzene molecules on Fe{sub 4} cluster. Highlights: Black-Right-Pointing-Pointer We studied the interactions of iron clusters with benzene molecules. Black-Right-Pointing-Pointer We have used density functional theory based methods for Fe{sub 4} and benzene. Black-Right-Pointing-Pointer The physicochemical properties were determined for the ground states. Black-Right-Pointing-Pointer The ground state structures for the Fe{sub 4}-benzene species were determined. - Abstract: Geometrical rice-ball structures of the Fe{sub 4} cluster with capped adsorbed benzene molecules for neutral, anion, and cation species, Fe{sub 4}-(C{sub 6}H{sub 6}){sub m} (m Less-Than-Or-Slanted-Equal-To 3), are studied by means of all-electron calculations done with the BPW91 approach of density functional theory jointly with 6-311++G(2d, 2p) basis sets. Electronic properties like ionization energies and electron affinities as well as binding energies are estimated and are in good agreement with recently reported experimental results. The computed IR spectra for these species show vibrational bands near those of the isolated benzene molecule and some forbidden IR modes of this ligand become IR active in Fe{sub 4}-(C{sub 6}H{sub 6}){sub m} (m Less-Than-Or-Slanted-Equal-To 3). The metal-benzene bonding issue was studied through the contour plots of molecular orbitals, showing signatures of metal-carbon bonding, originated from the 3d electrons of Fe{sub 4} and the 2p{pi} electrons of benzene.

  9. Rotation in a gravitational billiard

    Science.gov (United States)

    Peraza-Mues, G. G.; Carvente, Osvaldo; Moukarzel, Cristian F.

    Gravitational billiards composed of a viscoelastic frictional disk bouncing on a vibrating wedge have been studied previously, but only from the point of view of their translational behavior. In this work, the average rotational velocity of the disk is studied under various circumstances. First, an experimental realization is briefly presented, which shows sustained rotation when the wedge is tilted. Next, this phenomenon is scrutinized in close detail using a precise numerical implementation of frictional forces. We show that the bouncing disk acquires a spontaneous rotational velocity whenever the wedge angle is not bisected by the direction of gravity. Our molecular dynamics (MD) results are well reproduced by event-driven (ED) simulations. When the wedge aperture angle θW>π/2, the average tangential velocity Rω¯ of the disk scales with the typical wedge vibration velocity vb, and is in general a nonmonotonic function of the overall tilt angle θT of the wedge. The present work focuses on wedges with θW=2π/3, which are relevant for the problem of spontaneous rotation in vibrated disk packings. This study makes part of the PhD Thesis of G. G. Peraza-Mues.

  10. Rotational diffusion in dense suspensions

    NARCIS (Netherlands)

    Hagen, M. H. J.; Frenkel, D.; Lowe, C.P.

    1999-01-01

    We have computed the rotational diffusion coefficient for a suspension of hard spheres. We find excellent agreement with experimental results over a density range up to, and including, the colloidal crystal. However, we find that theories derived to second order in the volume fraction overestimate

  11. Ultrasonography of the Rotator Cuff

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Yong Cheol [Samsung Medica Center, Sungkyunkwan University College of Medicine, Seoul (Korea, Republic of)

    2006-09-15

    The ultrasonography (US) is an important modality in evaluating shoulder disease. It is accurate in diagnosing the various shoulder diseases including tendinosis, calcific tendinitis, and subacromial bursitis as well as rotator cuff tears. This article presents a pictorial review of US anatomy of the shoulder, the technical aspects of shoulder US, major types of shoulder pathology, and interventional procedure under US guidance

  12. Ultrasonography of the Rotator Cuff

    International Nuclear Information System (INIS)

    Yoon, Yong Cheol

    2006-01-01

    The ultrasonography (US) is an important modality in evaluating shoulder disease. It is accurate in diagnosing the various shoulder diseases including tendinosis, calcific tendinitis, and subacromial bursitis as well as rotator cuff tears. This article presents a pictorial review of US anatomy of the shoulder, the technical aspects of shoulder US, major types of shoulder pathology, and interventional procedure under US guidance

  13. Visual and Haptic Mental Rotation

    Directory of Open Access Journals (Sweden)

    Satoshi Shioiri

    2011-10-01

    Full Text Available It is well known that visual information can be retained in several types of memory systems. Haptic information can also be retained in a memory because we can repeat a hand movement. There may be a common memory system for vision and action. On the one hand, it may be convenient to have a common system for acting with visual information. On the other hand, different modalities may have their own memory and use retained information without transforming specific to the modality. We compared memory properties of visual and haptic information. There is a phenomenon known as mental rotation, which is possibly unique to visual representation. The mental rotation is a phenomenon where reaction time increases with the angle of visual target (eg,, a letter to identify. The phenomenon is explained by the difference in time to rotate the representation of the target in the visual sytem. In this study, we compared the effect of stimulus angle on visual and haptic shape identification (two-line shapes were used. We found that a typical effect of mental rotation for the visual stimulus. However, no such effect was found for the haptic stimulus. This difference cannot be explained by the modality differences in response because similar difference was found even when haptical response was used for visual representation and visual response was used for haptic representation. These results indicate that there are independent systems for visual and haptic representations.

  14. A rotating arc plasma invertor

    International Nuclear Information System (INIS)

    Reusch, M.F.; Jayaram, K.

    1987-02-01

    A device is described for the inversion of direct current to alternating current. The main feature is the use of a rotating plasma arc in crossed electric and magnetic fields as a switch. This device may provide an economic alternative to other inversion methods in some circumstances

  15. Holder for rotating glass body

    International Nuclear Information System (INIS)

    Kolleck, F.W.

    1978-01-01

    A device is provided for holding and centering a rotating glass body such as a rod or tube. The device includes a tubular tip holder which may be held in a lathe chuck. The device can utilize a variety of centering tips each adapted for a particular configuration, such as a glass O-ring joint or semi-ball joint

  16. Rotational disorder in lithium borohydride

    NARCIS (Netherlands)

    Remhof, Arndt; Yan, Yigang; Embs, Jan Peter; Sakai, Victoria Garcia; Nale, Angeloclaudio; de Jongh, Petra; Lodziana, Zbigniew; Zuettel, Andreas

    2015-01-01

    LiBH4 has been discussed as a promising hydrogen storage material and as a solid-state electrolyte in lithiumion batteries. It contains 18.5 wt% hydrogen and undergoes a structural phase transition at 381K which is associated with a large increase in rotational disorder of the [BH4](-) anion and the

  17. Transport due to rotational pumping

    International Nuclear Information System (INIS)

    Crooks, S. M.; O'Neil, T. M.

    1995-01-01

    An effect which we call rotational pumping (by analogy with magnetic pumping) causes cross-field transport in nonneutral plasmas when the end confinement potentials are non-axisymmetric. Because the Debye length is small the asymmetries are screened out within the plasma, but cause the surface of the plasma to distort. As a flux tube of plasma undergoes ExB drift rotation about the center of the column, the length of the tube oscillates about some mean value and the P parallel dV work produces a corresponding oscillation in T parallel. In turn the collisional relaxation of T parallel toward T perpendicular produces a slow disspiation of electrostatic energy into heat and a consequent radial expansion (cross-field transport) of the plasma. Detailed comparisons between theory and experiment have been made for the case where the asymmetry is produced by displacing the column off-axis, that is, by creating an m=1 diocotron mode (see paper by Cluggish and Driscoll in these proceedings). The theory is generalized to include time dependent asymmetries. For the case where the asymmetry is a traveling wave that rotates faster than the ExB drift rotation of the plasma the particle flux is directed radially inward

  18. Complications of intertrochanteric rotational osteotomy

    Energy Technology Data Exchange (ETDEWEB)

    Braunstein, E.M.; Weissman, B.N.; Sosman, J.L.; Drew, M.

    1983-11-01

    Intertrochanteric anterior rotational osteotomy is a recently developed surgical procedure to treat osteonecrosis of the femoral head. We reviewed the radiographic findings in four cases to acquaint radiologists with the usual appearance of the procedure and to assess surgical complications. In all cases, immediate postoperative radiographs showed rotation of the necrotic portion of the femoral head anteriorly so that it was no longer weight-bearing. Clinical and radiologic follow-up ranged from 12 to 30 months. In this time, three patients developed complications, including nonunion of the osteotomy, further osteonecrosis with collapse of the femoral head, and worsening pain in the absence of progressive radiologic change. Radiology provides an important means of assessing rotational osteotomy, particularly in demonstrating sufficient rotation of the femoral head to assure nonweight-bearing by diseased bone. Also, surgical complications such as nonunion and hardware loosening may be identified. Nevertheless, the patient may deteriorate clinically even in the absence of radiologic demonstration of disease pregression, and the absence of radiographic change does not assure a successful surgical outcome.

  19. Complications of intertrochanteric rotational osteotomy

    International Nuclear Information System (INIS)

    Braunstein, E.M.; Weissman, B.N.; Sosman, J.L.; Drew, M.

    1983-01-01

    Intertrochanteric anterior rotational osteotomy is a recently developed surgical procedure to treat osteonecrosis of the femoral head. We reviewed the radiographic findings in four cases to acquaint radiologists with the usual appearance of the procedure and to assess surgical complications. In all cases, immediate postoperative radiographs showed rotation of the necrotic portion of the femoral head anteriorly so that it was no longer weight-bearing. Clinical and radiologic follow-up ranged from 12 to 30 months. In this time, three patients developed complications, including nonunion of the osteotomy, further osteonecrosis with collapse of the femoral head, and worsening pain in the absence of progressive radiologic change. Radiology provides an important means of assessing rotational osteotomy, particularly in demonstrating sufficient rotation of the femoral head to assure nonweight-bearing by diseased bone. Also, surgical complications such as nonunion and hardware loosening may be identified. Nevertheless, the patient may deteriorate clinically even in the absence of radiologic demonstration of disease pregression, and the absence of radiographic change does not assure a successful surgical outcome. (orig.)

  20. Alternative Gravity Rotation Curves for the LITTLE THINGS Survey

    Science.gov (United States)

    O’Brien, James G.; Chiarelli, Thomas L.; Dentico, Jeremy; Stulge, Modestas; Stefanski, Brian; Moss, Robert; Chaykov, Spasen

    2018-01-01

    Galactic rotation curves have proven to be the testing ground for dark matter bounds in spiral galaxies of all morphologies. Dwarf galaxies serve as an increasingly interesting case of rotation curve dynamics due to their typically rising rotation curve as opposed to the flattening curve of large spirals. Dwarf galaxies usually vary in galactic structure and mostly terminate at small radial distances. This, coupled with the fact that Cold Dark Matter theories struggle with the universality of galactic rotation curves, allow for exclusive features of alternative gravitational models to be analyzed. Recently, The H I Nearby Galactic Survey (THINGS) has been extended to include a sample of 25 dwarf galaxies now known as the LITTLE THINGS Survey. Here, we show an application of alternative gravitational models to the LITTLE THINGS survey, specifically focusing on conformal gravity (CG) and Modified Newtonian Dynamics (MOND). In this work, we provide an analysis and discussion of the rotation curve predictions of each theory to the sample. Furthermore, we show how these two alternative gravitational models account for the recently observed universal trends in centripetal accelerations in spiral galaxies. This work highlights the similarities and differences of the predictions of the two theories in dwarf galaxies. The sample is not large or diverse enough to strongly favor a single theory, but we posit that both CG and MOND can provide an accurate description of the galactic dynamics in the LITTLE THINGS sample without the need for dark matter.

  1. macula: Rotational modulations in the photometry of spotted stars

    Science.gov (United States)

    Kipping, David M.

    2012-09-01

    Photometric rotational modulations due to starspots remain the most common and accessible way to study stellar activity. Modelling rotational modulations allows one to invert the observations into several basic parameters, such as the rotation period, spot coverage, stellar inclination and differential rotation rate. The most widely used analytic model for this inversion comes from Budding (1977) and Dorren (1987), who considered circular, grey starspots for a linearly limb darkened star. That model is extended to be more suitable in the analysis of high precision photometry such as that by Kepler. Macula, a Fortran 90 code, provides several improvements, such as non-linear limb darkening of the star and spot, a single-domain analytic function, partial derivatives for all input parameters, temporal partial derivatives, diluted light compensation, instrumental offset normalisations, differential rotation, starspot evolution and predictions of transit depth variations due to unocculted spots. The inclusion of non-linear limb darkening means macula has a maximum photometric error an order-of-magnitude less than that of Dorren (1987) for Sun-like stars observed in the Kepler-bandpass. The code executes three orders-of-magnitude faster than comparable numerical codes making it well-suited for inference problems.

  2. The Complete Molecular Geometry of Salicyl Aldehyde from Rotational Spectroscopy

    Science.gov (United States)

    Dorosh, O.; Bialkowska-Jaworska, E.; Kisiel, Z.; Pszczolkowski, L.; Kanska, M.; Krygowski, T. M.; Maeder, H.

    2013-06-01

    Salicyl aldehyde is a well known planar molecule containing an internal hydrogen bond. In preparing the publication of our previous report of the study of its rotational spectrum we have taken the opportunity to update the structure determination of this molecule to the complete r_e^{SE} geometry. The molecule contains 15 atoms and we have used supersonic expansion FTMW spectroscopy to obtain rotational constants for a total 26 different isotopic species, including all singly substitued species relative to the parent molecule. The ^{13}C and ^{18}O substitutions were measured in natural abundance, while deuterium substitutions were carried out synthetically. The r_e^{SE} determination requires the calculation of vibration-rotation changes in rotational constants from an ab initio anharmonic force field, which necessitates some compromises in the level of calculation for a molecule of the size of salicyl aldehyde. For this reason we studied the five lowest vibrationally excited states, by using the combination of room-temperature mm-wave spectroscopy and waveguide Fourier transform cm-wave spectroscopy. The experimental excited state rotational constants were then used to calibrate the anharmonic force field calculation. The resulting r_e^{SE} geometry is compared with other types of geometry determination possible from this data, with emphasis on the effect of the near zero principal coordinate of the important C_2 atom. Z.Kisiel et al., 61^{st} OSU Symposium on Molecular Spectroscopy, The Ohio State University, Ohio 2006, RI-12.

  3. Midplane Faraday rotation: A densitometer for large tokamaks

    International Nuclear Information System (INIS)

    Jobes, F.C.; Mansfield, D.K.

    1992-01-01

    The density in a large tokamak such as International Thermonuclear Experimental Reactor (ITER), or any of the proposed future US machines, can be determined by measuring the Faraday rotation of a 10.6 μm laser directed tangent to the toroidal field. If there is a horizontal array of such beams, then n e (R) can be readily obtained with a simple Abel inversion about the center line of the tokamak. For a large machine, operated at a full field of 30 T m and a density of 2x10 20 /m 3 , the rotation angle would be quite large-about 60 degree for two passes. A layout in which a single laser beam is fanned out in the horizontal midplane of the tokamak, with a set of retroreflectors on the far side of the vacuum vessel, would provide good spatial resolution, depending only upon the number of reflectors. With this proposed layout, only one window would be needed. Because the rotation angle is never more than 1 ''fringe,'' the data is always good, and it is also a continuous measurement in time. Faraday rotation is dependent only upon the plasma itself, and thus is not sensitive to vibration of the optical components. Simulations of the expected results show that ITER, or any large tokamak, existing or proposed, would be well served even at low densities by a midplane Faraday rotation densitometer of ∼64 channels

  4. Distributions of methyl group rotational barriers in polycrystalline organic solids

    Energy Technology Data Exchange (ETDEWEB)

    Beckmann, Peter A., E-mail: pbeckman@brynmawr.edu, E-mail: wangxianlong@uestc.edu.cn [Department of Physics, Bryn Mawr College, 101 North Merion Ave., Bryn Mawr, Pennsylvania 19010-2899 (United States); Conn, Kathleen G. [Department of Physics, Bryn Mawr College, 101 North Merion Ave., Bryn Mawr, Pennsylvania 19010-2899 (United States); Division of Education and Human Services, Neumann University, One Neumann Drive, Aston, Pennsylvania 19014-1298 (United States); Mallory, Clelia W. [Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6323 (United States); Department of Chemistry, Bryn Mawr College, 101 North Merion Ave., Bryn Mawr, Pennsylvania 19010-2899 (United States); Mallory, Frank B. [Department of Chemistry, Bryn Mawr College, 101 North Merion Ave., Bryn Mawr, Pennsylvania 19010-2899 (United States); Rheingold, Arnold L. [Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Dr., La Jolla, California 92093-0358 (United States); Rotkina, Lolita [Regional Nanotechnology Facility, Laboratory for Research on the Structure of Matter, University of Pennsylvania, 3231 Walnut Street, Philadelphia, Pennsylvania 19104-6202 (United States); Wang, Xianlong, E-mail: pbeckman@brynmawr.edu, E-mail: wangxianlong@uestc.edu.cn [Key Laboratory for NeuroInformation of Ministry of Education, School of Life Science and Technology, University of Electronic Science and Technology, 4 North Jianshe Rd., 2nd Section, Chengdu 610054 (China)

    2013-11-28

    We bring together solid state {sup 1}H spin-lattice relaxation rate measurements, scanning electron microscopy, single crystal X-ray diffraction, and electronic structure calculations for two methyl substituted organic compounds to investigate methyl group (CH{sub 3}) rotational dynamics in the solid state. Methyl group rotational barrier heights are computed using electronic structure calculations, both in isolated molecules and in molecular clusters mimicking a perfect single crystal environment. The calculations are performed on suitable clusters built from the X-ray diffraction studies. These calculations allow for an estimate of the intramolecular and the intermolecular contributions to the barrier heights. The {sup 1}H relaxation measurements, on the other hand, are performed with polycrystalline samples which have been investigated with scanning electron microscopy. The {sup 1}H relaxation measurements are best fitted with a distribution of activation energies for methyl group rotation and we propose, based on the scanning electron microscopy images, that this distribution arises from molecules near crystallite surfaces or near other crystal imperfections (vacancies, dislocations, etc.). An activation energy characterizing this distribution is compared with a barrier height determined from the electronic structure calculations and a consistent model for methyl group rotation is developed. The compounds are 1,6-dimethylphenanthrene and 1,8-dimethylphenanthrene and the methyl group barriers being discussed and compared are in the 2–12 kJ mol{sup −1} range.

  5. Structure of molecules and internal rotation

    CERN Document Server

    Mizushima, San-Ichiro

    1954-01-01

    Structure of Molecules and Internal Rotation reviews early studies on dihalogenoethanes. This book is organized into two parts encompassing 8 chapters that evaluate the Raman effect in ethane derivatives, the energy difference between rotational isomers, and the infrared absorption of ethane derivatives. Some of the topics covered in the book are the potential barrier to internal rotation; nature of the hindering potential; entropy difference between the rotational isomers; internal rotation in butane, pentane, and hexane; and internal rotation in long chain n-paraffins. Other chapters deal wi

  6. Magneto-rotational instability in differentially rotating liquid metals

    International Nuclear Information System (INIS)

    Velikhov, E.P.; Ivanov, A.A.; Lakhin, V.P.; Serebrennikov, K.S.

    2006-01-01

    We study the stability of Couette flow between two cylinders in the presence of axial magnetic field in local WKB approximation. We find the analytical expression of the critical angular velocity minimized over the wave number and the imposed magnetic field as a function of the measure of deviation of the rotation law from the Rayleigh line. The result found is in a good agreement with the previously known numerical results based on the global analysis. We perform a minimization of the critical Reynolds number over the wave number at fixed magnetic field both analytically and numerically. We show that a compromise between resistive suppression of magneto-rotational instability at weak magnetic field and the increase of the critical Reynolds number with the increase of magnetic field is possible. It takes place at moderate values of magnetic field of order 3x10 2 gauss giving the critical Reynolds number of order 4x10 4

  7. Nonclassical rotational inertia for a supersolid under rotation

    OpenAIRE

    Aftalion, Amandine; Blanc, Xavier; Jerrard, Robert L.

    2007-01-01

    As proposed by Leggett [4], the supersolidity of a crystal is characterized by the Non Classical Rotational Inertia (NCRI) property. Using a model of quantum crystal introduced by Josserand, Pomeau and Rica [5], we prove that NCRI occurs. This is done by analyzing the ground state of the aforementioned model, which is related to a sphere packing problem, and then deriving a theoretical formula for the inertia momentum. We infer a lower estimate for the NCRI fraction, which is a landmark of su...

  8. Flow-through PCR on a 3D qiandu-shaped polydimethylsiloxane (PDMS) microdevice employing a single heater: toward microscale multiplex PCR.

    Science.gov (United States)

    Wu, Wenming; Loan, Kieu The Loan; Lee, Nae Yoon

    2012-05-07

    Consistent temperature control in an on-chip flow-through polymerase chain reaction (PCR) employing two or more heaters is one of the main obstacles for device miniaturization and integration when realizing micro total analysis systems (μTAS), and also leads to operational complexity. In this study, we propose a qiandu (right triangular prism)-shaped polydimethylsiloxane (PDMS) microdevice with serpentine microchannels fabricated on its slanted plane, and apply the device for an on-chip flow-through PCR employing a single heater. The inclined nature of the qiandu-shaped microdevice enables the formation of a surface temperature gradient along the slanted plane of the microdevice in a height-dependent manner by the use of a single heater, and enables liquid to traverse over wide ranges of temperatures, including the three temperature zones--denaturation, annealing, and extension temperatures--required in a typical PCR. The feasibility of the qiandu-shaped PDMS microdevice as a versatile platform for performing a flow-through PCR was examined by employing multiple templates and varying the inclination angle of the device. In addition, the potential of performing a multiplex PCR using a single qiandu-shaped PDMS microdevice was explored. A 409 bp long gene fragment effective as a marker for diagnosing lung cancer and a 230 bp long gene fragment from a plasmid vector were simultaneously amplified in less than 25 min on a single microdevice, paving the way for a microscale, multiplex PCR on a single device employing a single heater.

  9. Aerospike Nozzle for Rotating Detonation Engine Application

    Data.gov (United States)

    National Aeronautics and Space Administration — This proposal presents a graduate MS research thesis on improving the efficiency of rotating detonation engines by using aerospike nozzle technologies. A rotating...

  10. Transformation of Real Spherical Harmonics under Rotations

    Science.gov (United States)

    Romanowski, Z.; Krukowski, St.; Jalbout, A. F.

    2008-08-01

    The algorithm rotating the real spherical harmonics is presented. The convenient and ready to use formulae for l = 0, 1, 2, 3 are listed. The rotation in R3 space is determined by the rotation axis and the rotation angle; the Euler angles are not used. The proposed algorithm consists of three steps. (i) Express the real spherical harmonics as the linear combination of canonical polynomials. (ii) Rotate the canonical polynomials. (iii) Express the rotated canonical polynomials as the linear combination of real spherical harmonics. Since the three step procedure can be treated as a superposition of rotations, the searched rotation matrix for real spherical harmonics is a product of three matrices. The explicit formulae of matrix elements are given for l = 0, 1, 2, 3, what corresponds to s, p, d, f atomic orbitals.

  11. SEG Advances in Rotational Seismic Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Pierson, Robert; Laughlin, Darren; Brune, Bob

    2016-10-17

    Significant advancements in the development of sensors to enable rotational seismic measurements have been achieved. Prototypes are available now to support experiments that help validate the utility of rotational seismic measurements.

  12. Area spectrum of slowly rotating black holes

    OpenAIRE

    Myung, Yun Soo

    2010-01-01

    We investigate the area spectrum for rotating black holes which are Kerr and BTZ black holes. For slowly rotating black holes, we use the Maggiore's idea combined with Kunstatter's method to derive their area spectra, which are equally spaced.

  13. Rotating black hole and quintessence

    International Nuclear Information System (INIS)

    Ghosh, Sushant G.

    2016-01-01

    We discuss spherically symmetric exact solutions of the Einstein equations for quintessential matter surrounding a black hole, which has an additional parameter (ω) due to the quintessential matter, apart from the mass (M). In turn, we employ the Newman-Janis complex transformation to this spherical quintessence black hole solution and present a rotating counterpart that is identified, for α = -e 2 ≠ 0 and ω = 1/3, exactly as the Kerr-Newman black hole, and as the Kerr black hole when α = 0. Interestingly, for a given value of parameter ω, there exists a critical rotation parameter (a = a E ), which corresponds to an extremal black hole with degenerate horizons, while for a < a E , it describes a nonextremal black hole with Cauchy and event horizons, and no black hole for a > a E . We find that the extremal value a E is also influenced by the parameter ω and so is the ergoregion. (orig.)

  14. Rotation sensing with trapped ions

    Science.gov (United States)

    Campbell, W. C.; Hamilton, P.

    2017-03-01

    We present a protocol for rotation measurement via matter-wave Sagnac interferometry using trapped ions. The ion trap based interferometer encloses a large area in a compact apparatus through repeated round-trips in a Sagnac geometry. We show how a uniform magnetic field can be used to close the interferometer over a large dynamic range in rotation speed and measurement bandwidth without contrast loss. Since this technique does not require the ions to be confined in the Lamb-Dicke regime, Doppler laser cooling should be sufficient to reach a sensitivity of { S }=1.4× {10}-6 {{rad}} {{{s}}}-1 {{{H}}{{z}}}-1/2. , which features invited work from the best early-career researchers working within the scope of J. Phys. B. This project is part of the Journal of Physics series’ 50th anniversary celebrations in 2017. Wes Campbell was selected by the Editorial Board of J. Phys. B as an Emerging Leader.

  15. Understand rotating isothermal collapses yet

    International Nuclear Information System (INIS)

    Tohline, J.E.

    1985-01-01

    A scalar virial equation is used to describe the dynamic properties of equilibrium gas clouds, taking into account the relative effects of surface pressure, rotation, self gravity and internal isothermal pressure. Details concerning the internal structure of the clouds are ignored in order to obtain a globalized analytical expression. The obtained solution to the equation is found to agree with the surface-pressure-dominated model of Stahler (1983), and the rotation-dominated model of Hayashi, Narita, and Miyama (1982). On the basis of the analytical expression of virial equilibrium in the clouds, some of the limiting properties of isothermal clouds are described, and a realistic starting model for cloud collapse is proposed. 18 references

  16. Alignment of suprathermally rotating grains

    Science.gov (United States)

    Lazarian, A.

    1995-12-01

    It is shown that mechanical alignment can be efficient for suprathermally rotating grains, provided that they drift with supersonic velocities. Such a drift should be widely spread due to both Alfvenic waves and ambipolar diffusion. Moreover, if suprathermal rotation is caused by grain interaction with a radiative flux, it is shown that mechanical alignment may be present even in the absence of supersonic drift. This means that the range of applicability of mechanical alignment is wider than generally accepted and that it can rival the paramagnetic one. We also study the latter mechanism and re-examine the interplay between poisoning of active sites and desorption of molecules blocking the access to the active sites of H_2 formation, in order to explain the observed poor alignment of small grains and good alignment of large grains. To obtain a more comprehensive picture of alignment, we briefly discuss the alignment by radiation fluxes and by grain magnetic moments.

  17. Gravitational lensing by rotating wormholes

    Science.gov (United States)

    Jusufi, Kimet; Ã-vgün, Ali

    2018-01-01

    In this paper the deflection angle of light by a rotating Teo wormhole spacetime is calculated in the weak limit approximation. We mainly focus on the weak deflection angle by revealing the gravitational lensing as a partially global topological effect. We apply the Gauss-Bonnet theorem (GBT) to the optical geometry osculating the Teo-Randers wormhole optical geometry to calculate the deflection angle. Furthermore we find the same result using the standard geodesic method. We have found that the deflection angle can be written as a sum of two terms, namely the first term is proportional to the throat of the wormhole and depends entirely on the geometry, while the second term is proportional to the spin angular momentum parameter of the wormhole. A direct observation using lensing can shed light and potentially test the nature of rotating wormholes by comparing with the black holes systems.

  18. Tidal variations of earth rotation

    Science.gov (United States)

    Yoder, C. F.; Williams, J. G.; Parke, M. E.

    1981-01-01

    The periodic variations of the earths' rotation resulting from the tidal deformation of the earth by the sun and moon were rederived including terms with amplitudes of 0.002 millisec and greater. The series applies to the mantle, crust, and oceans which rotate together for characteristic tidal periods; the scaling parameter is the ratio of the fraction of the Love number producing tidal variations in the moment of inertia of the coupled mantle and oceans (k) to the dimensionless polar moment of inertia of the coupled moments (C). The lunar laser ranging data shows that k/C at monthly and fortnightly frequencies equals 0.99 + or - 0.15 and 0.99 + or - 0.20 as compared to the theoretical value of 0.94 + or - 0.04.

  19. Secular stability of rotating stars

    International Nuclear Information System (INIS)

    Imamura, J.N.; Friedman, J.L.; Durisen, R.H.

    1984-01-01

    In this work, we calculate the secular stability limits of rotating polytropes to nonaxisymmetric perturbations of low m. We consider polytropic indices ranging from 1 to 3 and several angular momentum distributions. Results are most conveniently presented in terms of the t-parameter, defined as the ratio of the rotational kinetic energy to the absolute value of the gravitational energy of the fluid. Previous work on polytropes considered only the m = 2 mode, which is unstable for values of the t-parameter greater than 0.14 +- 0.01 for the n values n = 1.5 and 3 and the angular momentum distributions tested (see Durisen and Imamura 1981). The GRR secular stability limit of the m = 2 mode for the Maclaurin spheroids (n = O) was determined by Chandrasekhar (1970). GRR stability limits of higher m modes for the Maclaurin spheroids were located approximately by Comins (1979a,b) and more precisely by Friedman (1983)

  20. Accelerating and rotating black holes

    International Nuclear Information System (INIS)

    Griffiths, J B; Podolsky, J

    2005-01-01

    An exact solution of Einstein's equations which represents a pair of accelerating and rotating black holes (a generalized form of the spinning C-metric) is presented. The starting point is a form of the Plebanski-Demianski metric which, in addition to the usual parameters, explicitly includes parameters which describe the acceleration and angular velocity of the sources. This is transformed to a form which explicitly contains the known special cases for either rotating or accelerating black holes. Electromagnetic charges and a NUT parameter are included, the relation between the NUT parameter l and the Plebanski-Demianski parameter n is given, and the physical meaning of all parameters is clarified. The possibility of finding an accelerating NUT solution is also discussed

  1. Active media under rotational forcing

    Science.gov (United States)

    Pérez-Villar, Vicente; Porteiro, Jose L. F.; Muñuzuri, Alberto P.

    2006-10-01

    The bubble-free Belousov-Zhabotinsky reaction has been used to study the effects of centrifugal forces on autowave propagation. The reaction parameters were chosen such that the system oscillates naturally creating target waves. In the present study, the system was forced to rotate with a constant velocity around a central axis. In studying the effects of such a forcing on the system, we focused on target dynamics. The system reacts to this forcing in different ways, the most spectacular being a dramatic increase in the period of the target, the effect growing stronger as we move away from the center of rotation. A numerical study was carried out using the two-variable Oregonator model, modified to include convective effects through the diffusion coefficient. The numerical results showed a good qualitative agreement with those of the experiments.

  2. Ionospheric and receiver DCB-constrained multi-GNSS single-frequency PPP integrated with MEMS inertial measurements

    Science.gov (United States)

    Gao, Zhouzheng; Ge, Maorong; Shen, Wenbin; Zhang, Hongping; Niu, Xiaoji

    2017-11-01

    Single-frequency precise point positioning (SF-PPP) is a potential precise positioning technique due to the advantages of the high accuracy in positioning after convergence and the low cost in operation. However, there are still challenges limiting its applications at present, such as the long convergence time, the low reliability, and the poor satellite availability and continuity in kinematic applications. In recent years, the achievements in the dual-frequency PPP have confirmed that its performance can be significantly enhanced by employing the slant ionospheric delay and receiver differential code bias (DCB) constraint model, and the multi-constellation Global Navigation Satellite Systems (GNSS) data. Accordingly, we introduce the slant ionospheric delay and receiver DCB constraint model, and the multi-GNSS data in SF-PPP modular together. In order to further overcome the drawbacks of SF-PPP in terms of reliability, continuity, and accuracy in the signal easily blocking environments, the inertial measurements are also adopted in this paper. Finally, we form a new approach to tightly integrate the multi-GNSS single-frequency observations and inertial measurements together to ameliorate the performance of the ionospheric delay and receiver DCB-constrained SF-PPP. In such model, the inter-system bias between each two GNSS systems, the inter-frequency bias between each two GLONASS frequencies, the hardware errors of the inertial sensors, the slant ionospheric delays of each user-satellite pair, and the receiver DCB are estimated together with other parameters in a unique Kalman filter. To demonstrate its performance, the multi-GNSS and low-cost inertial data from a land-borne experiment are analyzed. The results indicate that visible positioning improvements in terms of accuracy, continuity, and reliability can be achieved in both open-sky and complex conditions while using the proposed model in this study compared to the conventional GPS SF-PPP.

  3. Perceptual strategies of pigeons to detect a rotational centre--a hint for star compass learning?

    Directory of Open Access Journals (Sweden)

    Bianca Alert

    Full Text Available Birds can rely on a variety of cues for orientation during migration and homing. Celestial rotation provides the key information for the development of a functioning star and/or sun compass. This celestial compass seems to be the primary reference for calibrating the other orientation systems including the magnetic compass. Thus, detection of the celestial rotational axis is crucial for bird orientation. Here, we use operant conditioning to demonstrate that homing pigeons can principally learn to detect a rotational centre in a rotating dot pattern and we examine their behavioural response strategies in a series of experiments. Initially, most pigeons applied a strategy based on local stimulus information such as movement characteristics of single dots. One pigeon seemed to immediately ignore eccentric stationary dots. After special training, all pigeons could shift their attention to more global cues, which implies that pigeons can learn the concept of a rotational axis. In our experiments, the ability to precisely locate the rotational centre was strongly dependent on the rotational velocity of the dot pattern and it crashed at velocities that were still much faster than natural celestial rotation. We therefore suggest that the axis of the very slow, natural, celestial rotation could be perceived by birds through the movement itself, but that a time-delayed pattern comparison should also be considered as a very likely alternative strategy.

  4. TERA for Rotating Equipment Selection

    OpenAIRE

    Khan, Raja S. R.

    2012-01-01

    This thesis looks at creating a multidisciplinary simulation tool for rotating plant equipment selection, specifically gas turbines, for the liquefaction of natural gas (LNG). This is a collaborative project between Shell Global Solutions and Cranfield University in the UK. The TERA LNG tool uses a Techno-economic, Environmental and Risk Analysis (TERA) approach in order to satisfy the multidisciplinary nature of the investigation. The benefits of the tool are to act as an aid ...

  5. Muon spin rotation in superconductors

    International Nuclear Information System (INIS)

    Gladisch, M.; Orth, H.; Putlitz, G. zu; Wahl, W.; Wigand, M.; Herlach, D.; Seeger, A.; Metz, H.; Teichler, H.

    1979-01-01

    By means of the muon spin rotation technique (μ + SR), the temperature dependence of the magnetic field inside the normal-conducting domains of high-purity tantalum crystals in the intermediate state has been measured in the temperature range 2.36 K + SR. Possible applications of these findings to the study of long-range diffusion of positive muons at low temperatures are indicated. (Auth.)

  6. Rotation of a Moonless Earth

    Science.gov (United States)

    Lissauer, Jack J.; Barnes, Jason W.; Chambers, John E.

    2013-01-01

    We numerically explore the obliquity (axial tilt) variations of a hypothetical moonless Earth. Previous work has shown that the Earth's Moon stabilizes Earth's obliquity such that it remains within a narrow range, between 22.1 deg and 24.5 deg. Without lunar influence, a frequency-map analysis by Laskar et al. showed that the obliquity could vary between 0 deg. and 85 deg. This has left an impression in the astrobiology community that a large moon is necessary to maintain a habitable climate on an Earth-like planet. Using a modified version of the orbital integrator mercury, we calculate the obliquity evolution for moonless Earths with various initial conditions for up to 4 Gyr. We find that while obliquity varies significantly more than that of the actual Earth over 100,000 year timescales, the obliquity remains within a constrained range, typically 20-25 deg. in extent, for timescales of hundreds of millions of years. None of our Solar System integrations in which planetary orbits behave in a typical manner show obliquity accessing more than 65% of the full range allowed by frequency-map analysis. The obliquities of moonless Earths that rotate in the retrograde direction are more stable than those of pro-grade rotators. The total obliquity range explored for moonless Earths with rotation periods shorter than 12 h is much less than that for slower-rotating moonless Earths. A large moon thus does not seem to be needed to stabilize the obliquity of an Earth-like planet on timescales relevant to the development of advanced life.

  7. Operating characteristics of rotating beds

    Energy Technology Data Exchange (ETDEWEB)

    Keyvani, M.; Gardner, N.C.

    1988-01-01

    Vapor-liquid contacting in high gravitational fields offers prospects for significant reductions in the physical size, capital, and operating costs of packed towers. Pressure drops, power requirements, mass transfer coefficients and liquid residence time distributions are reported for a rotating bed separator. The beds studied were rigid, foamed aluminum, with specific surface areas ranging from 650 to 3000 m{sup 2}/m{sup 2}. Gravitational fields were varied from 50 to 300g.

  8. Gravity controlled anti-reverse rotation device

    Science.gov (United States)

    Dickinson, Robert J.; Wetherill, Todd M.

    1983-01-01

    A gravity assisted anti-reverse rotation device for preventing reverse rotation of pumps and the like. A horizontally mounted pawl is disposed to mesh with a fixed ratchet preventing reverse rotation when the pawl is advanced into intercourse with the ratchet by a vertically mounted lever having a lumped mass. Gravitation action on the lumped mass urges the pawl into mesh with the ratchet, while centrifugal force on the lumped mass during forward, allowed rotation retracts the pawl away from the ratchet.

  9. Engineering Aspects of Single- and Twin-screw Extrusion-cooking of Biopolymers

    NARCIS (Netherlands)

    Zuilichem, D.J. van; Stolp, W.; Janssen, L.P.B.M.

    1983-01-01

    A survey is given of the properties of single- and twin-screw extruders. The influence on the design of the different leakage gaps existing in co-rotating, counter-rotating, self-wiping, twin-screw extruders and single-screw equipment is discussed. The mixing effects in single- and twin-screw

  10. Developing an Asteroid Rotational Theory

    Science.gov (United States)

    Geis, Gena; Williams, Miguel; Linder, Tyler; Pakey, Donald

    2018-01-01

    The goal of this project is to develop a theoretical asteroid rotational theory from first principles. Starting at first principles provides a firm foundation for computer simulations which can be used to analyze multiple variables at once such as size, rotation period, tensile strength, and density. The initial theory will be presented along with early models of applying the theory to the asteroid population. Early results confirm previous work by Pravec et al. (2002) that show the majority of the asteroids larger than 200m have negligible tensile strength and have spin rates close to their critical breakup point. Additionally, results show that an object with zero tensile strength has a maximum rotational rate determined by the object’s density, not size. Therefore, an iron asteroid with a density of 8000 kg/m^3 would have a minimum spin period of 1.16h if the only forces were gravitational and centrifugal. The short-term goal is to include material forces in the simulations to determine what tensile strength will allow the high spin rates of asteroids smaller than 150m.

  11. Microseismic sources of rotational type

    Science.gov (United States)

    Pasternak, Elena; Dyskin, Arcady; He, Junxian

    2017-04-01

    Traditionally the sources of seismic and microseismic events are related to shear fractures. The analysis of the seismic moment tensors of the sources associated with rock fracturing and hydraulic fracturing in the laboratory experiments and in-situ reveals that while there exist tensile and compressive sources, the shear sources prevail. The appearance of multiple shear sources, accompanied rock fracturing contradicts the results of the direct experiments suggesting that the rock as well as other materials not exhibiting clear plastic flow fail in tension. This contradiction is conventionally resolved by assuming the presence of multiple pre-existing shear fractures (faults or microfaults) whose sudden sliding provides microseismic events of shear type. We consider alternative mechanisms associated with bending of links between rotating particles and fragments of geomaterial and bending of bridges connecting opposite sides of hydraulic fractures. In both cases the fracturing is caused by the action of moments (or moment stresses) leading to bending, while at microscale the failure is associated with tensile microstresses leading to formation of tensile microcracks. In other words, at microscale the moment-related failure is failure in tension, as routinely observed in materials even in compression. It is easy to demonstrate that from a distance the sources of rotational type are equivalent to a standard double couple, similar to the one associated with shear fracturing. In other words what is currently interpreted as shear microseismic sources can in fact be rotational sources. This calls for new methods of detecting and interpreting microseismic sources; some possible methods are discussed.

  12. From Newton's bucket to rotating polygons

    DEFF Research Database (Denmark)

    Bach, B.; Linnartz, E. C.; Vested, Malene Louise Hovgaard

    2014-01-01

    and move from a rigidly rotating 'Newton's bucket' flow to one where bottom and cylinder wall are rotating oppositely and the surface is strongly turbulent but flat on average. Between those two extremes, we find polygonal states for which the rotational symmetry is spontaneously broken. We investigate...

  13. Rotating Polygons on a Fluid Surface

    DEFF Research Database (Denmark)

    Bohr, Tomas; Jansson, Thomas; Haspang, Martin

    The free surface of a rotating fluid will, due to the centrifugal force, be pressed radially outward. If the fluid rotates as a rigid body in a cylindrical container the surface will assume a parabolic shape. If, however, the flow is driven by rotating the bottom plate, the axial symmetry can break...

  14. Investigation of antimagnetic rotation in 100Pd

    International Nuclear Information System (INIS)

    Zhu, S.; Garg, U.; Afanasjev, A. V.; Frauendorf, S.; Kharraja, B.; Ghugre, S. S.; Chintalapudi, S. N.; Janssens, R. V. F.; Carpenter, M. P.; Kondev, F. G.

    2001-01-01

    High spin states have been studied in the nucleus 100 Pd with the aim of investigating the novel phenomenon of ''antimagnetic rotation.'' A cascade of four ''rotational-band-like'' transitions is proposed as corresponding to antimagnetic rotation, based on the observed spectroscopic properties and a comparison with calculations in the configuration-dependent cranked Nilsson-Strutinsky formalism

  15. On the Energy of Rotating Gravitational Waves

    OpenAIRE

    Mashhoon, Bahram; McClune, James C.; Chavez, Enrique; Quevedo, Hernando

    1996-01-01

    A class of solutions of the gravitational field equations describing vacuum spacetimes outside rotating cylindrical sources is presented. A subclass of these solutions corresponds to the exterior gravitational fields of rotating cylindrical systems that emit gravitational radiation. The properties of these rotating gravitational wave spacetimes are investigated. In particular, we discuss the energy density of these waves using the gravitational stress-energy tensor.

  16. Manual Training of Mental Rotation in Children

    Science.gov (United States)

    Wiedenbauer, Gunnar; Jansen-Osmann, Petra

    2008-01-01

    When deciding whether two stimuli rotated in space are identical or mirror reversed, subjects employ mental rotation to solve the task. In children mental rotation can be trained by extensive repetition of the task, but the improvement seems to rely on the retrieval of previously learned stimuli. We assumed that due to the close relation between…

  17. Visualizing Compound Rotations with Virtual Reality

    Science.gov (United States)

    Flanders, Megan; Kavanagh, Richard C.

    2013-01-01

    Mental rotations are among the most difficult of all spatial tasks to perform, and even those with high levels of spatial ability can struggle to visualize the result of compound rotations. This pilot study investigates the use of the virtual reality-based Rotation Tool, created using the Virtual Reality Modeling Language (VRML) together with…

  18. Measuring Stellar Rotation Periods with Kepler

    DEFF Research Database (Denmark)

    Nielsen, M. B.; Gizon, L.; Schunker, H.

    2013-01-01

    We measure rotation periods for 12151 stars in the Kepler field, based on photometric variability caused by stellar activity. Our analysis returns stable rotation periods over at least six out of eight quarters of Kepler data. This large sample of stars enables us to study rotation periods...

  19. What Is Rotating in Exploratory Factor Analysis?

    Science.gov (United States)

    Osborne, Jason W.

    2015-01-01

    Exploratory factor analysis (EFA) is one of the most commonly-reported quantitative methodology in the social sciences, yet much of the detail regarding what happens during an EFA remains unclear. The goal of this brief technical note is to explore what "rotation" is, what exactly is rotating, and why we use rotation when performing…

  20. Reliability of Isometric and Eccentric Isokinetic Shoulder External Rotation.

    Science.gov (United States)

    Papotto, Brianna M; Rice, Thomas; Malone, Terry; Butterfield, Timothy; Uhl, Tim L

    2016-06-06

    Shoulder external rotators are challenged eccentrically throughout the deceleration phase of throwing, which is thought to contribute to overuse injuries. To evaluate the effectiveness of intervention programs, as well as identifying deficits, reliable and responsive measures of isometric and eccentric shoulder external rotation are necessary. Previously, isometric measures have primarily tested a single position, and eccentric measures have not been found to have high reliability. To examine the between-days reliability of multiple-angle isometric and dynamic eccentric isokinetic testing of shoulder external rotation. Repeated measures. 10 healthy subjects (age 30 ± 12 y, height 166 ± 13 cm, mass 72 ± 10 kg). Average isometric peak torque of shoulder external rotation at 7 angles was measured. From these values, the angle of isometric peak torque was calculated. Dynamic eccentric average peak torque, average total work, and average angle of peak torque were measured. Between-days reliability was high for average peak torque during isometric contractions at all angles (ICC ≥ .85), as it was for dynamic eccentric average peak torque (ICC ≥ .97). The estimated angle of isometric peak torque (ICC ≤ .65) was not highly reliable between days. The average angle of peak torque from the eccentric testing produced inconsistent results. Average total work of dynamic eccentric shoulder external rotation was found to be highly reliable between days (ICC ≥ .97). Aspects of force such as peak torque and total work in isometric and eccentric testing of the shoulder external-rotator muscles can be measured reliably between days and used to objectively evaluate shoulder strength and identify changes when they occur. Angle measurements of peak torque could provide insight into the mechanical properties of the posterior shoulder muscles but were found to be inconsistent between days.

  1. Rotational joint assembly and method for constructing the same

    Science.gov (United States)

    Bandera, Pablo (Inventor); Buchele, Paul (Inventor)

    2012-01-01

    A rotational joint assembly and a method for constructing a rotational joint assembly are provided. The rotational joint assembly includes a first rotational component, a second rotational component coupled to the first rotational component such that the second rotational component is rotatable relative to the first rotational component in first and second rotational directions about an axis, and a flexure member, being deflectable in first and second deflection directions, coupled to at least one of the first and second rotational components such that when the second rotational component is rotated relative to the first rotational component in each of the first and second rotational directions about the axis, the flexure member is deflected in the first deflection direction and exerts a force on the second rotational component opposing the rotation.

  2. Rotational parameters using linearized theory of rotational states

    Energy Technology Data Exchange (ETDEWEB)

    Ullah, N.

    1985-03-01

    The problem of collective rotational parameters is studied using a new expansion of the good angular momentum states Vertical BarPsi/sub J/> and linearization procedure. It is shown that the approximation correctly reproduces Skyrme's formula. The approximation is applied to parametrize the value of the matrix element Vertical BarVertical Bar. The agreement with the values deduced from experimental data on the nuclei 1 /sub 64//sup 56/Gd/sub 92/ and 1 /sub 70//sup 76/Yb/sub 106/ is fairly good.

  3. Temperature dependent heterogeneous rotational correlation in lipids.

    Science.gov (United States)

    Dadashvand, Neda; Othon, Christina M

    2016-11-15

    Lipid structures exhibit complex and highly dynamic lateral structure; and changes in lipid density and fluidity are believed to play an essential role in membrane targeting and function. The dynamic structure of liquids on the molecular scale can exhibit complex transient density fluctuations. Here the lateral heterogeneity of lipid dynamics is explored in free standing lipid monolayers. As the temperature is lowered the probes exhibit increasingly broad and heterogeneous rotational correlation. This increase in heterogeneity appears to exhibit a critical onset, similar to those observed for glass forming fluids. We explore heterogeneous relaxation in in a single constituent lipid monolayer of 1, 2-dimyristoyl-sn-glycero-3-phosphocholine  by measuring the rotational diffusion of a fluorescent probe (1-palmitoyl-2-[1]-sn-glycero-3-phosphocholine), which is embedded in the lipid monolayer at low labeling density. Dynamic distributions are measured using wide-field time-resolved fluorescence anisotropy. The observed relaxation exhibits a narrow, liquid-like distribution at high temperatures (τ ∼ 2.4 ns), consistent with previous experimental measures (Dadashvand et al 2014 Struct. Dyn. 1 054701, Loura and Ramalho 2007 Biochim. Biophys. Acta 1768 467-478). However, as the temperature is quenched, the distribution broadens, and we observe the appearance of a long relaxation population (τ ∼ 16.5 ns). This supports the heterogeneity observed for lipids at high packing densities, and demonstrates that the nanoscale diffusion and reorganization in lipid structures can be significantly complex, even in the simplest amorphous architectures. Dynamical heterogeneity of this form can have a significant impact on the organization, permeability and energetics of lipid membrane structures.

  4. Visual perception of axes of head rotation

    Directory of Open Access Journals (Sweden)

    David Mattijs Arnoldussen

    2013-02-01

    Full Text Available Registration of ego-motion is important to accurately navigate through space. Movements of the head and eye relative to space are registered through the vestibular system and optical flow, respectively. Here, we address three questions concerning the visual registration of self-rotation. 1. Eye-in-head movements provide a link between the motion signals received by sensors in the moving eye and sensors in the moving head. How are these signals combined into an ego-rotation percept? We combined optic flow of simulated forward and rotational motion of the eye with different levels of eye-in-head rotation for a stationary head. We dissociated simulated gaze rotation and head rotation by different levels of eye-in-head pursuit.We found that perceived rotation matches simulated head- not gaze-rotation. This rejects a model for perceived self-rotation that relies on the rotation of the gaze line. Rather, eye-in-head signals serve to transform the optic flow’s rotation information, that specifies rotation of the scene relative to the eye, into a rotation relative to the head. This suggests that transformed visual self-rotation signals may combine with vestibular signals.2. Do transformed visual self-rotation signals reflect the arrangement of the semicircular canals (SCC? Previously, we found sub-regions within MST and V6+ that respond to the speed of the simulated head rotation. Here, we re-analyzed those BOLD signals for the presence of a spatial dissociation related to the axes of visually simulated head rotation, such as have been found in sub-cortical regions of various animals. Contrary, we found a rather uniform BOLD response to simulated rotation along the three SCC axes.3. We investigated if subject’s sensitivity to the direction of the head rotation axis shows SCC axes specifcity. We found that sensitivity to head rotation is rather uniformly distributed, suggesting that in human cortex, visuo-vestibular integration is not arranged into

  5. Friction, Free Axes of Rotation and Entropy

    Directory of Open Access Journals (Sweden)

    Alexander Kazachkov

    2017-03-01

    Full Text Available Friction forces acting on rotators may promote their alignment and therefore eliminate degrees of freedom in their movement. The alignment of rotators by friction force was shown by experiments performed with different spinners, demonstrating how friction generates negentropy in a system of rotators. A gas of rigid rotators influenced by friction force is considered. The orientational negentropy generated by a friction force was estimated with the Sackur-Tetrode equation. The minimal change in total entropy of a system of rotators, corresponding to their eventual alignment, decreases with temperature. The reported effect may be of primary importance for the phase equilibrium and motion of ubiquitous colloidal and granular systems.

  6. Visual perception of axes of head rotation

    Science.gov (United States)

    Arnoldussen, D. M.; Goossens, J.; van den Berg, A. V.

    2013-01-01

    Registration of ego-motion is important to accurately navigate through space. Movements of the head and eye relative to space are registered through the vestibular system and optical flow, respectively. Here, we address three questions concerning the visual registration of self-rotation. (1) Eye-in-head movements provide a link between the motion signals received by sensors in the moving eye and sensors in the moving head. How are these signals combined into an ego-rotation percept? We combined optic flow of simulated forward and rotational motion of the eye with different levels of eye-in-head rotation for a stationary head. We dissociated simulated gaze rotation and head rotation by different levels of eye-in-head pursuit. We found that perceived rotation matches simulated head- not gaze-rotation. This rejects a model for perceived self-rotation that relies on the rotation of the gaze line. Rather, eye-in-head signals serve to transform the optic flow's rotation information, that specifies rotation of the scene relative to the eye, into a rotation relative to the head. This suggests that transformed visual self-rotation signals may combine with vestibular signals. (2) Do transformed visual self-rotation signals reflect the arrangement of the semi-circular canals (SCC)? Previously, we found sub-regions within MST and V6+ that respond to the speed of the simulated head rotation. Here, we re-analyzed those Blood oxygenated level-dependent (BOLD) signals for the presence of a spatial dissociation related to the axes of visually simulated head rotation, such as have been found in sub-cortical regions of various animals. Contrary, we found a rather uniform BOLD response to simulated rotation along the three SCC axes. (3) We investigated if subject's sensitivity to the direction of the head rotation axis shows SCC axes specifcity. We found that sensitivity to head rotation is rather uniformly distributed, suggesting that in human cortex, visuo-vestibular integration is

  7. Examining cotton in rotation with rice and cotton in rotation with other crops using natural experiment

    Science.gov (United States)

    Sun, Ling; Zhu, Zesheng

    2017-08-01

    This paper is to show the ability of remote sensing image analysis combined with statistical analysis to characterize the environmental risk assessment of cotton in rotation with rice and cotton in rotation with other crops in two ways: (1) description of rotation period of cotton in rotation with rice and cotton in rotation with other crops by the observational study or natural experiment; (2) analysis of rotation period calculation of cotton in rotation with rice and cotton in rotation with other crops. Natural experimental results show that this new method is very promising for determining crop rotation period for estimating regional averages of environmental risk. When it is applied to determining crop rotation period, two requested remote sensing images of regional crop are required at least.

  8. Rotation and Accretion Powered Pulsars

    Energy Technology Data Exchange (ETDEWEB)

    Kaspi, V M [Department of Physics, McGill University, 3600 University St, Montreal, QC H3A 2T8 (Canada)

    2008-03-07

    Pulsar astrophysics has come a long way in the 40 years since the discovery of the first pulsar by Bell and Hewish. From humble beginnings as bits of 'scruff' on the Cambridge University group's chart recorder paper, the field of pulsars has blossomed into a major area of mainstream astrophysics, with an unparalleled diversity of astrophysical applications. These range from Nobel-celebrated testing of general relativity in the strong-field regime to constraining the equation-of-state of ultradense matter; from probing the winds of massive stars to globular cluster evolution. Previous notable books on the subject of pulsars have tended to focus on some particular topic in the field. The classic text Pulsars by Manchester and Taylor (1977 San Francisco, CA: Freeman) targeted almost exclusively rotation-powered radio pulsars, while the Meszaros book High-Energy Radiation from Magnetized Neutron Stars (1992 Chicago, IL: University of Chicago Press) considered both rotation- and accretion-powered neutron stars, but focused on their radiation at x-ray energies and above. The recent book Neutron Stars 1 by Haensel et al (2007 Berlin: Springer) considers only the equation of state and neutron-star structure. Into this context appears Rotation and Accretion Powered Pulsars, by Pranab Ghosh. In contrast to other books, here the author takes an encyclopedic approach and attempts to synthesize practically all of the major aspects of the two main types of neutron star. This is ambitious. The only comparable undertaking is the useful but more elementary Lyne and Graham-Smith text Pulsar Astronomy (1998 Cambridge: Cambridge University Press), or Compact Stellar X-ray Sources (eds Lewin and van der Klis, 2006 Cambridge: Cambridge University Press), an anthology of technical review articles that also includes black hole topics. Rotation and Accretion Powered Pulsars thus fills a clear void in the field, providing a readable, graduate-level book that covers nearly

  9. Effects of Constant Time Delay Procedure on the Halliwick's Method of Swimming Rotation Skills for Children with Autism

    Science.gov (United States)

    Yilmaz, Ilker; Konukman, Ferman; Birkan, Binyamin; Ozen, Arzu; Yanardag, Mehmet; Camursoy, Ilhan

    2010-01-01

    Effects of a constant time delay procedure on the Halliwick's method of swimming rotation skills (i.e., vertical and lateral rotation) for children with autism were investigated. A single subject multiple baseline model across behaviors with probe conditions was used. Participants were three boys, 8-9 years old. Data were collected over a 10-week…

  10. On the stability of rotational discontinuities

    International Nuclear Information System (INIS)

    Richter, P.; Scholer, M.

    1989-01-01

    The stability of symmetric rotational discontinuities in which the magnetic field rotates by 180 degree is investigated by means of a one-dimensional self-consistent hybrid code. Rotational discontinuities with an angle Θ > 45 degree between the discontinuity normal direction and the upstream magnetic field are found to be relatively stable. The discontinuity normal is in the x direction and the initial magnetic field has finite y component only in the transition region. In the case of the ion (left-handed) sense of rotation of the tangential magnetic field, the transition region does not broaden with time. In the case of the electron (right-handed) sense of rotation, a damped wavetrain builds up in the B y component downstream of the rotational discontinuity and the discontinuity broadens with time. Rotational discontinuities with smaller angles, Θ, are unstable. Examples for a rotational discontinuity with Θ = 30 degree and the electron sense of rotation as well as a rotational discontinuity with Θ = 15 degree and the ion sense of rotation show that these discontinuities into waves. These waves travel approximately with Alfven velocity in the upstream direction and are therefore phase standing in the simulation system. The magnetic hodograms of these disintegrated discontinuities are S-shaped. The upstream portion of the hodogram is always right-handed; the downstream portion is always left-handed

  11. Staff rotation: implications for occupational therapy.

    Science.gov (United States)

    Taylor, A; Andriuk, M L; Langlois, P; Provost, E

    1995-10-01

    Occupational therapy departments of tertiary care hospitals can provide staff with opportunities to gain diverse clinical experience if they rotate through the various services such as surgery, medicine, geriatrics, plastic surgery and orthopaedics. The system of rotation offers both advantages and disadvantages for the staff and the institution. The Royal Victoria Hospital in Montreal, a large university teaching hospital, had traditionally offered staff the opportunity to rotate. Changes in staffing and their needs however, resulted in rotation becoming an important issue within the department. This article presents the pros and the cons of rotation and non-rotation systems as identified by therapists and administrators across Canada. Staff rotation was found to have an effect on job satisfaction and a therapist's career orientation. Given these findings, administrators may want to reconsider the role of the generalist and specialist in their facilities.

  12. Rotational inertia and multimodal heaviness perception.

    Science.gov (United States)

    Streit, Matthew; Shockley, Kevin; Riley, Michael A

    2007-10-01

    Perceived heaviness of wielded objects has been shown to be a function of the objects' rotational inertia--the objects' resistance to rotational acceleration. Studies have also demonstrated that if virtual objects rotate faster than the actual wielded object (i.e., a rotational gain is applied to virtual object motion), the wielded object is perceived as systematically lighter. The present research determined whether combining those inertial and visual manipulations would influence heaviness perception in a manner consistent with an inertial model of multimodal heaviness perception. Rotational inertia and optical rotational gain of wielded objects were manipulated to specify inertia multimodally. Both visual and haptic manipulations significantly influenced perceived heaviness. The results suggest that rotational inertia is detected multimodally and that multimodal heaviness perception conforms to an inertial model.

  13. K2 ROTATION PERIODS FOR LOW-MASS HYADS AND THE IMPLICATIONS FOR GYROCHRONOLOGY

    Energy Technology Data Exchange (ETDEWEB)

    Douglas, S. T.; Agüeros, M. A. [Columbia University, Department of Astronomy, 550 West 120th Street, New York, NY 10027 (United States); Covey, K. R. [Western Washington University, Department of Physics and Astronomy, Bellingham, WA 98225 (United States); Cargile, P. A. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Barclay, T.; Cody, A.; Howell, S. B. [NASA Ames Research Center, Moffett Field, CA 94035 (United States); Kopytova, T. [Max-Planck-Institut für Astronomie, Königstuhl 17, D-69117 Heidelberg (Germany)

    2016-05-01

    As the closest open cluster to the Sun, the Hyades is an important benchmark for many stellar properties, but its members are also scattered widely over the sky. Previous studies of stellar rotation in the Hyades relied on targeted observations of single stars or data from shallower all-sky variability surveys. The re-purposed Kepler mission, K2 , is the first opportunity to measure rotation periods ( P {sub rot}) for many Hyads simultaneously while also being sensitive to fully convective M dwarf members. We analyze K2 data for 65 Hyads and present P {sub rot} values for 48. Thirty-seven of these are new measurements, including the first P {sub rot} measurements for fully convective Hyads. For 9 of the 11 stars with P {sub rot} in the literature and this work, the measurements are consistent; we attribute the two discrepant cases to spot evolution. Nearly all stars with masses ≲0.3 M {sub ⊙} are rapidly rotating, indicating a change in rotation properties at the boundary to full convection. When confirmed and candidate binaries are removed from the mass–period plane, only three rapid rotators with masses ≳0.3 M {sub ⊙} remain. This is in contrast to previous results showing that the single-valued mass–period sequence for ≈600 Myr old stars ends at ≈0.65 M {sub ⊙} when binaries are included. We also find that models of rotational evolution predict faster rotation than is actually observed at ≈600 Myr for stars ≲0.9 M {sub ⊙}. The dearth of single rapid rotators more massive than ≈0.3 M {sub ⊙} indicates that magnetic braking is more efficient than previously thought, and that age–rotation studies must account for multiplicity.

  14. Rotational dependence of Fermi-type resonance interactions in molecules

    Science.gov (United States)

    Mikhailov, Vladimir M.; Smirnov, M. A.

    1997-03-01

    In Pasadena, (Milliken Lab., USA, 1930) F. Rossetti has observed in Raman spectrum of carbon-dioxide molecule the full symmetric vibration of carbon dioxide appeared as the group of four near lying lines instead of the waited single line. The true interpretation of this enigmatic effect (in that time) was given by E. Fermi -- accidental degeneration of the first excited state of the full symmetric vibration in carbon dioxide. It was the first example of the event observed later in various organic molecules. This event was named as resonance Fermi. The rotational dependence of Fermi type resonance interactions in quasirigid molecules in dominant approximation can be selected in an expansion of the effective vibration-rotation Hamiltonian Hvib- roteff by the operator H(g)(Fermi) equals H30 plus (Sigma) nH3n(g). Let us consider in detail the problem of the construction of the effective vibration-rotational Hamiltonian HVR yields Heff from the point of view of various ordering schemes (grouping) of the vibrational-rotational interactions with sequential analysis of the choice of the convenient grouping adequate to the spectroscopic problem.

  15. Protostellar formation in rotation interstellar clouds. III. Nonaxisymmetric collapse

    International Nuclear Information System (INIS)

    Boss, A.P.

    1980-01-01

    A full three spatial-dimension gravitational hydrodynamics code has been used to follow the collapse of isothermal rotating clouds subjected to various nonaxialy symmetric perturbations (NAP). An initially axially symmetric cloud collapsed to form a ring which then fragmented into a binary protostellar system. A low thermal energy cloud with a large bar-shaped NAP collapsed and fragmented directly into a binary; higher thermal energy clouds damp out such NAPs while higher rotational rotational energy clouds produce binaries with wider separations. Fragmentation into single and binary systems has been seen. The tidal effects of other nearby protostellar clouds are shown to have an important effect upon the collapse and should not be neglected. The three-dimensional calculations indicate that isothermal interstellar clouds may fragment (with or without passing through a transitory ring phase) into protostellar objects while still in the isothermal regime. The fragments obtained have masses and specific spin angular momenta roughly a 10th that of the original cloud. Interstellar clouds and their fragments may pass through successive collapse phases with fragmentation and reduction of spin angular momentum (by conversion to orbital angular momentum and preferential accretion of low angular momentum matter) terminating in the formation of pre--main-sequence stars with the observed pre--main-sequence rotation rates

  16. High-Resolution Rotational Spectroscopy of a Molecular Rotary Motor

    Science.gov (United States)

    Domingos, Sergio R.; Cnossen, Arjen; Perez, Cristobal; Buma, Wybren Jan; Browne, Wesley R.; Feringa, Ben L.; Schnell, Melanie

    2017-06-01

    To develop synthetic molecular motors and machinery that can mimic their biological counterparts has become a stimulating quest in modern synthetic chemistry. Gas phase studies of these simpler synthetic model systems provide the necessary isolated conditions that facilitate the elucidation of their structural intricacies. We report the first high-resolution rotational study of a synthetic molecular rotary motor based on chiral overcrowded alkenes using chirp-pulsed Fourier transform microwave spectroscopy. Rotational constants and quartic centrifugal distortion constants were determined based on a fit using more than two hundred rotational transitions spanning 5≤J≤21 in the 2-4 GHz frequency range. Despite the lack of polar groups, the rotor's asymmetry produces strong a- and b-type rotational transitions arising from a single predominant conformer. Evidence for fragmentation of the rotor allows for unambiguous identification of the isolated rotor components. The experimental spectroscopic parameters of the rotor are compared and discussed against current high-level ab initio and density functional theory methods. Vicario et al. Chem. Commun., 5910-5912 (2005) Brown et al. Rev. Sci. Instrum., 79, 053103 (2008)

  17. Rotating safety drum nuclear reactor

    International Nuclear Information System (INIS)

    Schneider, R.T.

    1978-01-01

    A gas cooled nuclear fission reactor employing spherical fuel elements which are held in a critical assembly configuration by centrifugal forces. This is accomplished by inserting the spherical fuel elements in a rotating drum of a shape suitable to ensure that a nuclear critical configuration of the total entity of fuel elements can only be achieved if the centrifugal forces are present. This has the effect that in case of a loss of load, a loss of coolant or other adverse occurrences, the critical part of the reactor will disassemble itself, by gravitational forces exclusively, into a non-critical configuration

  18. ROTATIONAL VELOCITIES FOR M DWARFS

    International Nuclear Information System (INIS)

    Jenkins, J. S.; Ramsey, L. W.; Jones, H. R. A.; Pavlenko, Y.; Barnes, J. R.; Pinfield, D. J.; Gallardo, J.

    2009-01-01

    We present spectroscopic rotation velocities (v sin i) for 56 M dwarf stars using high-resolution Hobby-Eberly Telescope High Resolution Spectrograph red spectroscopy. In addition, we have also determined photometric effective temperatures, masses, and metallicities ([Fe/H]) for some stars observed here and in the literature where we could acquire accurate parallax measurements and relevant photometry. We have increased the number of known v sin i values for mid M stars by around 80% and can confirm a weakly increasing rotation velocity with decreasing effective temperature. Our sample of v sin is peak at low velocities (∼3 km s -1 ). We find a change in the rotational velocity distribution between early M and late M stars, which is likely due to the changing field topology between partially and fully convective stars. There is also a possible further change in the rotational distribution toward the late M dwarfs where dust begins to play a role in the stellar atmospheres. We also link v sin i to age and show how it can be used to provide mid-M star age limits. When all literature velocities for M dwarfs are added to our sample, there are 198 with v sin i ≤ 10 km s -1 and 124 in the mid-to-late M star regime (M3.0-M9.5) where measuring precision optical radial velocities is difficult. In addition, we also search the spectra for any significant Hα emission or absorption. Forty three percent were found to exhibit such emission and could represent young, active objects with high levels of radial-velocity noise. We acquired two epochs of spectra for the star GJ1253 spread by almost one month and the Hα profile changed from showing no clear signs of emission, to exhibiting a clear emission peak. Four stars in our sample appear to be low-mass binaries (GJ1080, GJ3129, Gl802, and LHS3080), with both GJ3129 and Gl802 exhibiting double Hα emission features. The tables presented here will aid any future M star planet search target selection to extract stars with low v

  19. The rotation of spiral galaxies.

    Science.gov (United States)

    Rubin, V C

    1983-06-24

    There is accumulating evidence that as much as 90 percent of the mass of the universe is nonluminous and is clumped, halo-like, around individual galaxies. The gravitational force of this dark matter is presumed to be responsible for the high rotational velocities of stars and gas in the disks of spiral galaxie. At present, the form of the dark matter is unknown. Possible candidates span a range in mass of 10(70), from non-zero-mass neutrinos to massive black holes.

  20. Nondestructive testing bench without rotation

    International Nuclear Information System (INIS)

    Perdijon, J.

    1976-01-01

    On-line testing by ultrasonics in combination with eddy currents represents a large saving in time and equipment since the tube to be checked only needs to pass once quickly and without rotation. The answer to this problem is to use encircling transducers, which means that the mirror interposed to detect transverse defects must be conical while that used to detect longitudinal defects is helically shaped. A cell combining these two mirrors with an eddy current coil to test thin small-diameter tubes is described. The first trial year shows that defects are detected independently of their position, with a sensitivity at least equal to that of conventional systems [fr

  1. Optical wheel-rotation sensor

    Science.gov (United States)

    Veeser, Lynn R.; Rodriguez, Patrick A.; Forman, Peter; Deeter, Merritt N.

    1994-09-01

    We describe a fiber-optic rotation sensor being developed for anti-lock braking systems. The basis of the sensor is the magneto-optic detection of the magnetic fields generated by a wheel of alternating magnetized magnets fixed to a wheel of the automobile. Highly sensitive iron garnet crystals serve as the magneto-optic sensing elements. For films with perpendicularly- magnetized domains, the domain structure produces diffraction which is magnetic-field dependent. Exploitation of this effect permits the construction of magneto-optic magnetic field sensors requiring no polarization elements or lenses.

  2. Microscopic approaches to nuclear rotations

    International Nuclear Information System (INIS)

    Ng, W.Y.

    1973-01-01

    The Skyrme formula for the nuclear moment of inertia, which was first derived from a variational principle, can also be deduced from the presumption of rotational bands and intrinsic states. In the present work a formula complementary to the Skyrme formula is first developed using the same technique and approximations. A statistial interpretation indicates that this new formula and the usual Skyrme formula provide reasonable upper and lower bounds for the true inertial parameter. A third formula is then developed which yields values between these bounds. It is concluded that the third Skyrme formula gives superior results. (author)

  3. Design of rotating electrical machines

    CERN Document Server

    Pyrhonen , Juha; Hrabovcova , Valeria

    2013-01-01

    In one complete volume, this essential reference presents an in-depth overview of the theoretical principles and techniques of electrical machine design. This timely new edition offers up-to-date theory and guidelines for the design of electrical machines, taking into account recent advances in permanent magnet machines as well as synchronous reluctance machines. New coverage includes: Brand new material on the ecological impact of the motors, covering the eco-design principles of rotating electrical machinesAn expanded section on the design of permanent magnet synchronous machines, now repo

  4. Generalization of stochastic visuomotor rotations.

    Directory of Open Access Journals (Sweden)

    Hugo L Fernandes

    Full Text Available Generalization studies examine the influence of perturbations imposed on one movement onto other movements. The strength of generalization is traditionally interpreted as a reflection of the similarity of the underlying neural representations. Uncertainty fundamentally affects both sensory integration and learning and is at the heart of many theories of neural representation. However, little is known about how uncertainty, resulting from variability in the environment, affects generalization curves. Here we extend standard movement generalization experiments to ask how uncertainty affects the generalization of visuomotor rotations. We find that although uncertainty affects how fast subjects learn, the perturbation generalizes independently of uncertainty.

  5. Parallel computation of rotating flows

    DEFF Research Database (Denmark)

    Lundin, Lars Kristian; Barker, Vincent A.; Sørensen, Jens Nørkær

    1999-01-01

    This paper deals with the simulation of 3‐D rotating flows based on the velocity‐vorticity formulation of the Navier‐Stokes equations in cylindrical coordinates. The governing equations are discretized by a finite difference method. The solution is advanced to a new time level by a two‐step process...... is that of solving a singular, large, sparse, over‐determined linear system of equations, and the iterative method CGLS is applied for this purpose. We discuss some of the mathematical and numerical aspects of this procedure and report on the performance of our software on a wide range of parallel computers. Darbe...

  6. A Rotating-Bears Optical Dipole Trap for Cold Aatoms

    International Nuclear Information System (INIS)

    Friedman, N.; Ozeri, R.; Khaykovich, L.; Davidson, N.

    1999-01-01

    In the last few years, several optical dipole traps for cold atoms were demonstrated and used to study cold atomic collisions, long atomic coherence times and quantum collective effects. Blue-detuned dipole traps, where repulsive light forces confines atoms mostly in dark, offer long storage, and photon-scattering times, combined with strong confinement forces. Unfortunately, such blue-detuned dipole traps involve complicated light intensity distributions that require either multiple laser beams or complicated phase elements. Here, we propose and demonstrate a novel configuration for a single-beam blue-detuned dipole trap, which enables larger trapping volume, and fast temporal changes in the trap size and shape. Our trap consists of a tightly-focused laser beam which is rapidly rotated (with rotation frequency up to 400 khz) with two orthogonal acousto optical scanners. For very high rotation frequencies the atoms feel a time-averaged static dipole potential. Therefore, when the radius of rotation is larger than the beam size, a dark volume which is completely surrounded by light is obtained around the focal region. By changing the rotation radius and the trapping laser intensity and detuning, the trap dimensions and oscillation frequency could be changed over a large parameter range. In particular trap diameters were changed between 50 to 220 microns and trap length was changed between 3.5 to 16 mm. ∼10 6 atoms were loaded into the rotating-beam dipole trap from a magneto optical trap. The density of the trapped atoms was 4x10 10 atoms/cm 3 ,their temperature was -6 pK. and the trap (1/e) lifetime was 0.65 sec, limited by collisions with background atoms. When the rotation frequency was decreased below the oscillation frequency of the atoms in the trap, the trap became unstable, and a sharp reduction of the trap lifetime was observed, in agreement with our theoretical analysis. Finally, we demonstrated adiabatic compression of atoms in the trap by decreasing

  7. Rotating effects on the Landau quantization for an atom with a magnetic quadrupole moment

    Energy Technology Data Exchange (ETDEWEB)

    Fonseca, I. C.; Bakke, K., E-mail: kbakke@fisica.ufpb.br [Departamento de Física, Universidade Federal da Paraíba, Caixa Postal 5008, João Pessoa, PB 58051-970 (Brazil)

    2016-01-07

    Based on the single particle approximation [Dmitriev et al., Phys. Rev. C 50, 2358 (1994) and C.-C. Chen, Phys. Rev. A 51, 2611 (1995)], the Landau quantization associated with an atom with a magnetic quadrupole moment is introduced, and then, rotating effects on this analogue of the Landau quantization is investigated. It is shown that rotating effects can modify the cyclotron frequency and breaks the degeneracy of the analogue of the Landau levels.

  8. Molecular Viscosity Sensors with Two Rotators for Optimizing the Fluorescence Intensity-Contrast Trade-Off.

    Science.gov (United States)

    Lee, Seung-Chul; Lee, Chang-Lyoul; Heo, Jeongyun; Jeong, Chan-Uk; Lee, Gyeong-Hui; Kim, Sehoon; Yoon, Woojin; Yun, Hoseop; Park, Sung O; Kwak, Sang Kyu; Park, Sung-Ha; Kwon, O-Pil

    2018-02-26

    A series of fluorescent molecular rotors obtained by introducing two rotational groups ("rotators"), which exhibit different rotational and electron-donating abilities, are discussed. Whereas the control molecular rotor, PH, includes a single rotator (the widely used phenyl group), the PO molecular rotors consist of two rotators (a phenyl group and an alkoxy group), which exhibit simultaneous strongly electron-donating and easy rotational abilities. Compared with the control rotor PH, PO molecular rotors exhibited one order of magnitude higher quantum yield (fluorescence intensity) and simultaneously exhibited significantly higher fluorescence contrast. These properties are directly related to the strong electron-donating ability and low energy barrier of rotation of the alkoxy group, as confirmed by dynamic fluorescence experiments and quantum chemical calculations. The PO molecular rotors exhibited two fluorescence relaxation pathways, whereas the PH molecular rotor exhibited a single fluorescence relaxation pathway. Cellular fluorescence imaging with PO molecular rotors for mapping cellular viscosity was successfully demonstrated. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Design of Multilevel Sequential Rotation Feeding Networks Used for Circularly Polarized Microstrip Antenna Arrays

    Directory of Open Access Journals (Sweden)

    Aixin Chen

    2012-01-01

    Full Text Available Sequential rotation feeding networks can significantly improve performance of the circularly polarized microstrip antenna array. In this paper, single, double, and multiple series-parallel sequential rotation feeding networks are examined. Compared with conventional parallel feeding structures, these multilevel feeding techniques present reduction of loss, increase of bandwidth, and improvement of radiation pattern and polarization purity. By using corner-truncated square patch as the array element and adopting appropriate level of sequential rotation series-parallel feeding structures as feeding networks, microstrip arrays can generate excellent circular polarization (CP over a relatively wide frequency band. They can find wide applications in phased array radar and satellite communication systems.

  10. MEASUREMENT OF THE RESISTIVE WALL MODE STABILITY IN A ROTATING PLASMA USING ACTIVE MHD SPECTROSCOPY

    International Nuclear Information System (INIS)

    CHU, M.S; JACKSON, G.L; LA HAYE, R.J; SCOVILLE, J.T; STRAIT, E.J

    2003-01-01

    The stability of the resistive-wall mode (RWM) in DIII-D plasmas above the conventional pressure limit, where toroidal plasma rotation in the order of a few percent of the Alfven velocity is sufficient to stabilize the n=1 RWM, has been probed using the technique of active MHD spectroscopy at frequencies of a few Hertz. The measured frequency spectrum of the plasma response to externally applied rotating resonant magnetic fields is well described by a single mode approach and provides an absolute measurement of the damping rate and the natural mode rotation frequency of the stable RWM

  11. Formulation of the rotational transformation of wave fields and their application to digital holography.

    Science.gov (United States)

    Matsushima, Kyoji

    2008-07-01

    Rotational transformation based on coordinate rotation in Fourier space is a useful technique for simulating wave field propagation between nonparallel planes. This technique is characterized by fast computation because the transformation only requires executing a fast Fourier transform twice and a single interpolation. It is proved that the formula of the rotational transformation mathematically satisfies the Helmholtz equation. Moreover, to verify the formulation and its usefulness in wave optics, it is also demonstrated that the transformation makes it possible to reconstruct an image on arbitrarily tilted planes from a wave field captured experimentally by using digital holography.

  12. Evidence for Bolgiano-Obukhov scaling in rotating stratified turbulence using high-resolution direct numerical simulations

    Science.gov (United States)

    Rosenberg, Duane; Pouquet, Annick; Marino, Raffaele; Mininni, Pablo

    2015-04-01

    at a scale at which the partition of energy between the kinetic and potential modes changes abruptly, and beyond which a Kolmogorov-like spectrum recovers. Large slanted layers are ubiquitous in the flow in the velocity and temperature fields, with local overturning events indicated by small gradient Richardson numbers and strong nonlinear potential vorticity. A small enhancement of energy at scales larger than the initial conditions and directly attributable to the effect of rotation is also occurring. If time permits, small-scale properties will also be described.

  13. Sol-gel chemistry synthesis and DTA-TGA, XRPD, SIC and {sup 7}Li, {sup 31}P, {sup 29}Si MAS-NMR studies on the Li-NASICON Li{sub 3}Zr{sub 2-y}Si{sub 2-4y}P{sub 1+4y}O{sub 12} (0 Less-Than-Or-Slanted-Equal-To y Less-Than-Or-Slanted-Equal-To 0.5) system

    Energy Technology Data Exchange (ETDEWEB)

    Belam, W., E-mail: WahidBelam@yahoo.fr [Chemistry Department, Bizerta Science Faculty, 7021 Jarzouna, Bizerta (Tunisia)

    2013-02-25

    Highlights: Black-Right-Pointing-Pointer The samples of Li-NASICON were elaborated by sol-gel chemistry. Black-Right-Pointing-Pointer The calcined temperatures of the studied samples were deduced from their thermograms. Black-Right-Pointing-Pointer The recorded X-ray powder diffractograms were indexed in the rhombohedral system. Black-Right-Pointing-Pointer The synthesized Li-NASICON materials are excellent lithium fast cation conductors. - Abstract: Five selected compounds of Li-NASICON, Li{sub 3}Zr{sub 2-y}Si{sub 2-4y}P{sub 1+4y}O{sub 12} (0 Less-Than-Or-Slanted-Equal-To y Less-Than-Or-Slanted-Equal-To 0.5), were synthesized by sol-gel chemistry in order to obtain pure polycrystalline powder and then analyzed by different physicochemical characterizations such as coupled DTA (differential thermal analysis)-TGA (thermogravimetric analysis), XRPD (X-ray powder diffraction), CIS (complex impedance spectroscopy) and MAS (magic angle spinning)-NMR (nuclear magnetic resonance). So the calcined temperature of each sample has been deduced from its corresponding DTA-TGA thermogram. However, the recorded X-ray powder diffractograms were indexed in the rhombohedral system with R3{sup Macron }c space group which corresponds to the ideal structure of NASICON. Whereas, the complex impedance spectroscopy study showed that these Li-NASICON materials are excellent lithium fast cation conductors with total electric conductivity maximal value 1.97 Multiplication-Sign 10{sup -3} S cm{sup -1} at 293 K in the case of Li{sub 3}Zr{sub 1.5}P{sub 3}O{sub 12}. Furthermore, {sup 7}Li, {sup 31}P and {sup 29}Si MAS-NMR spectroscopy study and DFT/B3LYP theoretical calculations of chemical shifts were performed to discuss the ambiguousness that exists between the resonance peak number in the experimental spectrum and the crystallographic site number relative to Li{sub 3}Zr{sub 2}Si{sub 2}PO{sub 12}.

  14. Neovascularization prevalence in the supraspinatus of patients with rotator cuff tendinopathy.

    Science.gov (United States)

    Kardouni, Joseph R; Seitz, Amee L; Walsworth, Matthew K; Michener, Lori A

    2013-11-01

    A high prevalence of neovascularity in lower extremity tendinopathies has been reported. Neovascularity in those with rotator cuff tendinopathy exclusively has not been examined. The objective was to determine the prevalence of neovascularization in patients with rotator cuff tendinopathy compared with asymptomatic controls. Single-blind cross-sectional study. Research laboratory. Participants (n = 40; age = 44.9 years, 23-62 years; 20 females) with rotator cuff tendinopathy (n = 20) but without full-thickness rotator cuff tears, and asymptomatic controls that were age, gender, and hand dominance matched (n = 20) to the patients. The participants laying in supine had their shoulder positioned in internal rotation and extension. Ultrasound images were collected of the supraspinatus tendon and subacromial bursae in the transverse and longitudinal planes using a linear transducer in color Doppler mode. Images were assessed for neovascularization by 2 trained raters who were blinded to group (rotator cuff tendinopathy or asymptomatic group). No statistically significant difference in neovascularization was identified between participants with and without rotator cuff tendinopathy (χ = 0.13, df = 1, P = 0.72). Neovascularization was identified in 6 of 20 patients with rotator cuff tendinopathy (30%) and 5 of 20 asymptomatic control participants (25%). The authors found no differences in neovascularization rate in patients with rotator cuff tendinopathy (30%) and asymptomatic controls (25%). The study indicates that neovascularization is not related to presence of symptomatic tendinopathy in those with rotator cuff tendinopathy. Neovascularization may not be a relevant sonographic finding to aid the clinical assessment of those with rotator cuff tendinopathy.

  15. Short rotation Wood Crops Program

    Energy Technology Data Exchange (ETDEWEB)

    Wright, L.L.; Ehrenshaft, A.R.

    1990-08-01

    This report synthesizes the technical progress of research projects in the Short Rotation Woody Crops Program for the year ending September 30, 1989. The primary goal of this research program, sponsored by the US Department of Energy's Biofuels and Municipal Waste Technology Division, is the development of a viable technology for producing renewable feedstocks for conversion to biofuels. One of the more significant accomplishments was the documentation that short-rotation woody crops total delivered costs could be $40/Mg or less under optimistic but attainable conditions. By taking advantage of federal subsidies such as those offered under the Conservation Reserve Program, wood energy feedstock costs could be lower. Genetic improvement studies are broadening species performance within geographic regions and under less-than-optimum site conditions. Advances in physiological research are identifying key characteristics of species productivity and response to nutrient applications. Recent developments utilizing biotechnology have achieved success in cell and tissue culture, somaclonal variation, and gene-insertion studies. Productivity gains have been realized with advanced cultural studies of spacing, coppice, and mixed-species trials. 8 figs., 20 tabs.

  16. A nonsingular rotating black hole

    International Nuclear Information System (INIS)

    Ghosh, Sushant G.

    2015-01-01

    The spacetime singularities in classical general relativity are inevitable, as predicated by the celebrated singularity theorems. However, it is a general belief that singularities do not exist in Nature and that they are the limitations of the general relativity. In the absence of a welldefined quantum gravity, models of regular black holes have been studied. We employ a probability distribution inspired mass function m(r) to replace the Kerr black hole mass M to represent a nonsingular rotating black hole that is identified asymptotically (r >> k, k > 0 constant) exactly as the Kerr-Newman black hole, and as the Kerr black hole when k = 0. The radiating counterpart renders a nonsingular generalization of Carmeli's spacetime as well as Vaidya's spacetime, in the appropriate limits. The exponential correction factor changing the geometry of the classical black hole to remove the curvature singularity can also be motivated by quantum arguments. The regular rotating spacetime can also be understood as a black hole of general relativity coupled to nonlinear electrodynamics. (orig.)

  17. Ring wormholes via duality rotations

    Directory of Open Access Journals (Sweden)

    Gary W. Gibbons

    2016-09-01

    Full Text Available We apply duality rotations and complex transformations to the Schwarzschild metric to obtain wormhole geometries with two asymptotically flat regions connected by a throat. In the simplest case these are the well-known wormholes supported by phantom scalar field. Further duality rotations remove the scalar field to yield less well known vacuum metrics of the oblate Zipoy–Voorhees–Weyl class, which describe ring wormholes. The ring encircles the wormhole throat and can have any radius, whereas its tension is always negative and should be less than −c4/4G. If the tension reaches the maximal value, the geometry becomes exactly flat, but the topology remains non-trivial and corresponds to two copies of Minkowski space glued together along the disk encircled by the ring. The geodesics are straight lines, and those which traverse the ring get to the other universe. The ring therefore literally produces a hole in space. Such wormholes could perhaps be created by negative energies concentrated in toroidal volumes, for example by vacuum fluctuations.

  18. Rotational disorder in lithium borohydride

    Directory of Open Access Journals (Sweden)

    Remhof Arndt

    2015-01-01

    Full Text Available LiBH4 has been discussed as a promising hydrogen storage material and as a solid-state electrolyte in lithium-ion batteries. It contains 18.5 wt% hydrogen and undergoes a structural phase transition at 381 K which is associated with a large increase in rotational disorder of the [BH4]− anion and the increase of [Li]+ conductivity by three orders of magnitude. We investigated the [BH4]− anion dynamic in bulk LiBH4, in LiBH4-LiI solid solutions and in nano-confined LiBH4 by quasielastic neutron scattering, complemented by DFT calculations. In all cases the H-dynamics is dominated by thermally activated rotational jumps of the [BH4]− anion in the terahertz range. The addition of LiI as well as nano-confinement favours the disordered high temperature phase and lowers the phase transition below room temperatures. The results are discussed on the basis of first principles calculations and in relation to ionic conductivity of [Li]+.

  19. Reciprocally-Rotating Velocity Obstacles

    KAUST Repository

    Giese, Andrew

    2014-05-01

    © 2014 IEEE. Modern multi-agent systems frequently use highlevel planners to extract basic paths for agents, and then rely on local collision avoidance to ensure that the agents reach their destinations without colliding with one another or dynamic obstacles. One state-of-the-art local collision avoidance technique is Optimal Reciprocal Collision Avoidance (ORCA). Despite being fast and efficient for circular-shaped agents, ORCA may deadlock when polygonal shapes are used. To address this shortcoming, we introduce Reciprocally-Rotating Velocity Obstacles (RRVO). RRVO generalizes ORCA by introducing a notion of rotation for polygonally-shaped agents. This generalization permits more realistic motion than ORCA and does not suffer from as much deadlock. In this paper, we present the theory of RRVO and show empirically that it does not suffer from the deadlock issue ORCA has, permits agents to reach goals faster, and has a comparable collision rate at the cost of performance overhead quadratic in the (typically small) user-defined parameter δ.

  20. A stable high-speed rotational transmission system based on nanotubes

    International Nuclear Information System (INIS)

    Cai, Kun; Yin, Hang; Wei, Ning; Chen, Zhen; Shi, Jiao

    2015-01-01

    A stable rotational transmission system is designed with a single-walled carbon nanotube (SWCNT)-based motor and double-walled carbon nanotubes (DWCNTs)-based bearing. The system response is investigated using molecular dynamics (MD) simulation. It is found that the rotating motor can actuate the rotation of the inner tube in bearing because of the attraction between the two adjacent coaxial ends of motor and rotor (the inner tube in bearing). To have a stable nanostructure, each carbon atom on the adjacent ends of motor and rotor is bonded with a hydrogen atom. To obtain a stable high-speed rotational transmission system, both an armchair and a zigzag model are used in MD simulation. In each model, the motor with different diameters and rotational speeds is employed to examine the rotational transmission of corresponding DWCNTs. It is demonstrated that the long range van der Waals interaction between the adjacent ends of motor and rotor leads to a stable configuration of the adjacent ends, and further leads to a stable rotation of rotor when driven by a high-speed motor. As compared with the armchair model, the rotor in the zigzag model could reach a stable rotation mode much easier

  1. Percutaneous vertebroplasty with a high-quality rotational angiographic unit

    Energy Technology Data Exchange (ETDEWEB)

    Pedicelli, Alessandro [Department of Bioimaging and Radiological Sciences, Catholic University of Sacred Heart, Policl. A.Gemelli, l.go Gemelli 1, 00168 Rome (Italy)], E-mail: apedicelli@rm.unicatt.it; Rollo, Massimo [Department of Bioimaging and Radiological Sciences, Catholic University of Sacred Heart, Policl. A.Gemelli, l.go Gemelli 1, 00168 Rome (Italy)], E-mail: mrollo@rm.unicatt.it; Piano, Mariangela [Department of Bioimaging and Radiological Sciences, Catholic University of Sacred Heart, Policl. A.Gemelli, l.go Gemelli 1, 00168 Rome (Italy)], E-mail: mariangela.piano@gmail.com; Re, Thomas J. [Department of Bioimaging and Radiological Sciences, Catholic University of Sacred Heart, Policl. A.Gemelli, l.go Gemelli 1, 00168 Rome (Italy)], E-mail: tomjre@gmail.com; Cipriani, Maria C. [Department of Gerontology, Catholic University of Sacred Heart, Policl. A.Gemelli, l.go Gemelli 1, 00168 Rome (Italy)], E-mail: alexped@yahoo.com; Colosimo, Cesare [Department of Bioimaging and Radiological Sciences, Catholic University of Sacred Heart, Policl. A.Gemelli, l.go Gemelli 1, 00168 Rome (Italy)], E-mail: colosimo@rm.unicatt.it; Bonomo, Lorenzo [Department of Bioimaging and Radiological Sciences, Catholic University of Sacred Heart, Policl. A.Gemelli, l.go Gemelli 1, 00168 Rome (Italy)], E-mail: lbonomo@rm.unicatt.it

    2009-02-15

    We evaluated the reliability of a rotational angiographic unit (RA) with flat-panel detector as a single technique to guide percutaneous vertebroplasty (PVP) and for post-procedure assessment by 2D and 3D reformatted images. Fifty-five consecutive patients (104 vertebral bodies) were treated under RA fluoroscopy. Rotational acquisitions with 2D and 3D reconstruction were obtained in all patients for immediate post-procedure assessment. In complex cases, this technique was also used to evaluate the needle position during the procedure. All patients underwent CT scan after the procedure. RA and CT findings were compared. In all cases, a safe trans-pedicular access and an accurate control of the bone-cement injection were successfully performed with high-quality fluoroscopy, even at the thoracic levels and in case of vertebra plana. 2D and 3D rotational reconstructions permitted CT-like images that clearly showed needle position and were similar to CT findings in depicting intrasomatic implant-distribution. RA detected 40 cement leakages compared to 42 demonstrated by CT and showed overall 95% sensitivity and 100% specificity compared to CT for final post-procedure assessment. Our preliminary results suggest that high-quality RA is reliable and safe as a single technique for PVP guidance, control and post-procedure assessment. It permits fast and cost-effective procedures avoiding multi-modality imaging.

  2. Pressure Monitoring Using Hybrid fs/ps Rotational CARS

    Science.gov (United States)

    Kearney, Sean P.; Danehy, Paul M.

    2015-01-01

    We investigate the feasibility of gas-phase pressure measurements at kHz-rates using fs/ps rotational CARS. Femtosecond pump and Stokes pulses impulsively prepare a rotational Raman coherence, which is then probed by a high-energy 6-ps pulse introduced at a time delay from the Raman preparation. Rotational CARS spectra were recorded in N2 contained in a room-temperature gas cell for pressures from 0.1 to 3 atm and probe delays ranging from 10-330 ps. Using published self-broadened collisional linewidth data for N2, both the spectrally integrated coherence decay rate and the spectrally resolved decay were investigated as means for detecting pressure. Shot-averaged and single-laser-shot spectra were interrogated for pressure and the accuracy and precision as a function of probe delay and cell pressure are discussed. Single-shot measurement accuracies were within 0.1 to 6.5% when compared to a transducer values, while the precision was generally between 1% and 6% of measured pressure for probe delays of 200 ps or more, and better than 2% as the delay approached 300 ps. A byproduct of the pressure measurement is an independent but simultaneous measurement of the gas temperature.

  3. Option selection in whole-body rotation movements in gymnastics

    Directory of Open Access Journals (Sweden)

    Thomas HEINEN

    2016-03-01

    Full Text Available Abstract When a gymnast performs a somersault, the linear and angular momentum along with a particular control of inertia during the flight phase constrain the possibilities for action. Given the complexity and dynamic nature of the human moving system, one could argue that there exist a particular amount of stable coordination states when performing somersaults. The goal of this study was to explore the manifold of movement options and coordination states along with their differentiating parameters for a single somersault in gymnastics based on a simple mathematical model reflecting gymnast’s rotation behavior during the flight phase. Biomechanical parameters determining rotation behavior during a somersault were systematically varied with regard to a particular set of biomechanical constraints defining a successful somersault performance. Batch simulations revealed that from 10229760 simulation cycles only 655346 (approximately 6.41% led to successful somersault performance. A subsequent analysis of the movement option landscape for the optimum angular momentum revealed ten coordination states for a single somersault that could be clearly distinguished based on the simulation parameters. Taken the results together, it becomes apparent that it may be most advisable to perform a single somersault with a larger moment of inertia when achieving the tucked position, a longer duration to achieve the tucked position, a longer duration of staying tucked, and an intermediate moment of inertia during landing. This strategy comprises the largest amount of movement options associated with an upright landing and thus the highest probability of success when performing a single somersault.

  4. In touch with mental rotation: interactions between mental and tactile rotations and motor responses.

    Science.gov (United States)

    Lohmann, Johannes; Rolke, Bettina; Butz, Martin V

    2017-04-01

    Although several process models have described the cognitive processing stages that are involved in mentally rotating objects, the exact nature of the rotation process itself remains elusive. According to embodied cognition, cognitive functions are deeply grounded in the sensorimotor system. We thus hypothesized that modal rotation perceptions should influence mental rotations. We conducted two studies in which participants had to judge if a rotated letter was visually presented canonically or mirrored. Concurrently, participants had to judge if a tactile rotation on their palm changed direction during the trial. The results show that tactile rotations can systematically influence mental rotation performance in that same rotations are favored. In addition, the results show that mental rotations produce a response compatibility effect: clockwise mental rotations facilitate responses to the right, while counterclockwise mental rotations facilitate responses to the left. We conclude that the execution of mental rotations activates cognitive mechanisms that are also used to perceive rotations in different modalities and that are associated with directional motor control processes.

  5. Narrow-linewidth passband filter for ultraviolet rotational Raman imaging.

    Science.gov (United States)

    Finkelstein, N D; Lempert, W R; Miles, R B

    1997-04-15

    We present a narrow-passband spectral filter capable of frequency-resolved imaging of rotational Raman light scattering with strong spectral rejection of out-of-band Raman, Rayleigh, and Mie scattering. The filter is based on mercury-vapor absorption, and subsequent resonant fluorescence and has a passband of less than 1 cm(-1). It is paired with an injection-seeded, cavity-locked, frequency-tripled Ti:sapphire laser that produces >30 mJ/pulse of single-mode, tunable light in the vicinity of 253.7 nm. The laser and filter are combined to spectrally resolve scattering from individual rotational Raman lines of nitrogen and oxygen.

  6. Rotational laser cooling of vibrationally and translationally cold molecular ions

    DEFF Research Database (Denmark)

    Staanum, Peter; Højbjerre, Klaus; Skyt, Peter Sandegaard

    2010-01-01

    -molecular reactions with coherent light fields 8, 9 , for quantum-state-selected bi-molecular reactions 10, 11, 12 and for astrochemistry 12 . Here, we demonstrate rotational ground-state cooling of vibrationally and translationally cold MgH+ ions, using a laser-cooling scheme based on excitation of a single...... rovibrational transition 13, 14 . A nearly 15-fold increase in the rotational ground-state population of the X  1Σ+ electronic ground-state potential has been obtained. The resulting ground-state population of 36.7±1.2% is equivalent to that of a thermal distribution at about 20 K. The obtained cooling results...

  7. Biceps tendinitis in chronic rotator cuff tears: a histologic perspective.

    Science.gov (United States)

    Singaraju, Vamsi M; Kang, Richard W; Yanke, Adam B; McNickle, Allison G; Lewis, Paul B; Wang, Vincent M; Williams, James M; Chubinskaya, Susan; Romeo, Anthony A; Cole, Brian J

    2008-01-01

    Patients with chronic rotator cuff tears frequently have anterior shoulder pain attributed to the long head of the biceps brachii (LHBB) tendon. In this study, tenodesis or tenotomy samples and cadaveric controls were assessed by use of immunohistochemical and histologic methods to quantify inflammation, vascularity, and neuronal plasticity. Patients had moderate pain and positive results on at least 1 clinical test of shoulder function. The number of axons in the distal LHBB was significantly less in patients with biceps tendinitis. Calcitonin gene-related peptide and substance P immunostaining was predominantly within nerve roots and blood vessels. A moderate correlation (R = 0.5) was identified between LHBB vascularity and pain scores. On the basis of these results, we conclude that, in the context of rotator cuff disease, the etiology of anterior shoulder pain with macroscopic changes in the biceps tendon is related to the complex interaction of the tendon and surrounding soft tissues, rather than a single entity.

  8. Boundary layer control of rotating convection systems.

    Science.gov (United States)

    King, Eric M; Stellmach, Stephan; Noir, Jerome; Hansen, Ulrich; Aurnou, Jonathan M

    2009-01-15

    Turbulent rotating convection controls many observed features of stars and planets, such as magnetic fields, atmospheric jets and emitted heat flux patterns. It has long been argued that the influence of rotation on turbulent convection dynamics is governed by the ratio of the relevant global-scale forces: the Coriolis force and the buoyancy force. Here, however, we present results from laboratory and numerical experiments which exhibit transitions between rotationally dominated and non-rotating behaviour that are not determined by this global force balance. Instead, the transition is controlled by the relative thicknesses of the thermal (non-rotating) and Ekman (rotating) boundary layers. We formulate a predictive description of the transition between the two regimes on the basis of the competition between these two boundary layers. This transition scaling theory unifies the disparate results of an extensive array of previous experiments, and is broadly applicable to natural convection systems.

  9. Physics, Formation and Evolution of Rotating Stars

    CERN Document Server

    Maeder, André

    2009-01-01

    Rotation is ubiquitous at each step of stellar evolution, from star formation to the final stages, and it affects the course of evolution, the timescales and nucleosynthesis. Stellar rotation is also an essential prerequisite for the occurrence of Gamma-Ray Bursts. In this book the author thoroughly examines the basic mechanical and thermal effects of rotation, their influence on mass loss by stellar winds, the effects of differential rotation and its associated instabilities, the relation with magnetic fields and the evolution of the internal and surface rotation. Further, he discusses the numerous observational signatures of rotational effects obtained from spectroscopy and interferometric observations, as well as from chemical abundance determinations, helioseismology and asteroseismology, etc. On an introductory level, this book presents in a didactical way the basic concepts of stellar structure and evolution in "track 1" chapters. The other more specialized chapters form an advanced course on the gradua...

  10. Contained Modes In Mirrors With Sheared Rotation

    Energy Technology Data Exchange (ETDEWEB)

    Abraham J. Fetterman and Nathaniel J. Fisch

    2010-10-08

    In mirrors with E × B rotation, a fixed azimuthal perturbation in the lab frame can appear as a wave in the rotating frame. If the rotation frequency varies with radius, the plasma-frame wave frequency will also vary radially due to the Doppler shift. A wave that propagates in the high rotation plasma region might therefore be evanescent at the plasma edge. This can lead to radially localized Alfven eigenmodes with high azimuthal mode numbers. Contained Alfven modes are found both for peaked and non-peaked rotation profiles. These modes might be useful for alpha channeling or ion heating, as the high azimuthal wave number allows the plasma wave frequency in the rotating frame to exceed the ion cyclotron frequency. __________________________________________________

  11. Rotational coherence spectroscopy at FLASH. Toward dynamic studies in nanosuperfluids

    Energy Technology Data Exchange (ETDEWEB)

    Kickermann, Andreas

    2013-07-15

    The field of molecular physics, which is focusing on molecular motion in the transition states of physical, chemical, and biological changes, is a wide-spread research area. It strives to reveal the structural and functional properties of molecules, the chemical bonds between atoms and the time evolution. Many processes occurring in nature upon electronic excitation proceed on the ultrafast femtosecond timescale and can be triggered by modern ultrashort femtosecond-laser sources under laboratory conditions. In the present thesis pump-probe studies were performed to follow molecular motion using ultrashort light pulses in the nanometer wavelength range provided by an XUV freeelectron laser (FEL). In detail, alignment of molecular species in space under field-free conditions was investigated. In the specific case of rotational wave packets in molecules the rotational dynamics shows characteristic temporal features, which contain a wealth of information on molecular structure and give insight into molecular coupling mechanisms, i.e. rotational constants and transition frequencies. Within this thesis, Rotational Coherence Spectroscopy (RCS) reveals wave-packet motion observed by subsequent Coulomb explosion of Raman excited carbon monoxide, which results in a time-dependent asymmetry of spatial fragmentation patterns. With the method presented here, the time resolution to elucidate the fast dynamics of strong couplings can be pushed toward a single rotational period even for the fastest rotors. This is due to large pump-probe delays with small subpicosecond step size. This kind of spectroscopy can also be expanded to molecular species, which are not accessible by other powerful spectroscopic methods, such as Fourier-transform microwave spectroscopy (FTMW). Furthermore, it allows to measure weak molecular couplings on a long timescale (large pump-probe delays), e.g. couplings of molecules in a solution or molecules dissolved in quantum fluids. This is valuable to

  12. Rotational coherence spectroscopy at FLASH. Toward dynamic studies in nanosuperfluids

    International Nuclear Information System (INIS)

    Kickermann, Andreas

    2013-07-01

    The field of molecular physics, which is focusing on molecular motion in the transition states of physical, chemical, and biological changes, is a wide-spread research area. It strives to reveal the structural and functional properties of molecules, the chemical bonds between atoms and the time evolution. Many processes occurring in nature upon electronic excitation proceed on the ultrafast femtosecond timescale and can be triggered by modern ultrashort femtosecond-laser sources under laboratory conditions. In the present thesis pump-probe studies were performed to follow molecular motion using ultrashort light pulses in the nanometer wavelength range provided by an XUV freeelectron laser (FEL). In detail, alignment of molecular species in space under field-free conditions was investigated. In the specific case of rotational wave packets in molecules the rotational dynamics shows characteristic temporal features, which contain a wealth of information on molecular structure and give insight into molecular coupling mechanisms, i.e. rotational constants and transition frequencies. Within this thesis, Rotational Coherence Spectroscopy (RCS) reveals wave-packet motion observed by subsequent Coulomb explosion of Raman excited carbon monoxide, which results in a time-dependent asymmetry of spatial fragmentation patterns. With the method presented here, the time resolution to elucidate the fast dynamics of strong couplings can be pushed toward a single rotational period even for the fastest rotors. This is due to large pump-probe delays with small subpicosecond step size. This kind of spectroscopy can also be expanded to molecular species, which are not accessible by other powerful spectroscopic methods, such as Fourier-transform microwave spectroscopy (FTMW). Furthermore, it allows to measure weak molecular couplings on a long timescale (large pump-probe delays), e.g. couplings of molecules in a solution or molecules dissolved in quantum fluids. This is valuable to

  13. Can mergers make slowly rotating elliptical galaxies

    International Nuclear Information System (INIS)

    White, S.D.M.

    1979-01-01

    The results of numerical experiments are used to guide an analytic discussion of hyperbolic mergers among an uncorrelated galaxy population. The expected merger rate is derived as a function of progenitor mass and relative angular momentum, and is used to predict the distribution of the parameter V/sub c//sigma 0 for merger products where V/sub c/ is the maximum observed rotation velocity in a galaxy and sigma 0 is its central velocity dispersion. The median value of this parameter for mergers between comparable galaxies is estimated to be 0.65 and is higher than the observed value in any of the 14 galaxies for which data are available. It seems unlikely that most elliptical galaxies are the result of single or multiple mergers between initially unbound stellar systems; further observational and theoretical work is suggested which should lead to a conclusive test of this picture. The present arguments cannot, however, exclude formation from low angular momentum elliptical orbits

  14. Rotating Drive for Electrical-Arc Machining

    Science.gov (United States)

    Fransen, C. D.

    1986-01-01

    Rotating drive improves quality of holes made by electrical-arc machining. Mechanism (Uni-tek, rotary head, or equivalent) attached to electrical-arc system. Drive rotates electrode as though it were mechanical drill, while an arc disintegrates metal in workpiece, thereby creating hole. Rotating electrode method often used in electric-discharge machining. NASA innovation is application of technique to electrical-arc machining.

  15. Intrinsic rotation with gyrokinetic models

    International Nuclear Information System (INIS)

    Parra, Felix I.; Barnes, Michael; Catto, Peter J.; Calvo, Iván

    2012-01-01

    The generation of intrinsic rotation by turbulence and neoclassical effects in tokamaks is considered. To obtain the complex dependences observed in experiments, it is necessary to have a model of the radial flux of momentum that redistributes the momentum within the tokamak in the absence of a preexisting velocity. When the lowest order gyrokinetic formulation is used, a symmetry of the model precludes this possibility, making small effects in the gyroradius over scale length expansion necessary. These effects that are usually small become important for momentum transport because the symmetry of the lowest order gyrokinetic formulation leads to the cancellation of the lowest order momentum flux. The accuracy to which the gyrokinetic equation needs to be obtained to retain all the physically relevant effects is discussed.

  16. Rotation of the Solar Equator

    Science.gov (United States)

    Kotov, V. A.

    2017-06-01

    Regular measurements of the general magnetic field of the Sun, performed over about half a century at the Crimean Astrophysical Observatory, the J. Wilcox Solar Observatory, and five other observatories, are considered in detail for the time 1968 - 2016. They include more than twenty-six thousand daily values of the mean line-of-sight field strength of the visible solar hemisphere. On the basis of these values, the equatorial rotation period of the Sun is found to be 26.926(9) d (synodic). It is shown that its half-value coincides within error limits with both the main period of the magnetic four-sector structure, 13.4577(25) d, and the best-commensurate period of the slow motions of the major solar system bodies, 13.479(22) d (sidereal). The probability that the two periods coincide by chance is estimated to be about 10^{-7}. The true origin of this odd resonance is unknown.

  17. Magnetic rotation in Rubidium-84

    International Nuclear Information System (INIS)

    Shen Shuifa; Han Guangbing; Wen Shuxian; Wu Xiaoguang; He Chuangye; Li Guangsheng; Zhu Lihua; Yan Yupeng

    2013-01-01

    High-spin states in 84 Rb have been studied by using the 70 Zn ( 18 O, p3n) 84 Rb reaction at beam energy of 75 MeV, Three regular magnetic dipole bands including strong M1 and weak E2 transitions have been observed in this nucleus which shows the characteristic feature of magnetic rotation. These bands are interpreted in the projected shell model for the first time on the basis of the four-quasiparticle configuration of the type π(fp)⊗ π(g 9/2 2 )⊗ ν(g 9/2 ) . It is shown that the calculated sequence lies roughly in the same energy range as the experimental one but the interval between neighboring levels is larger than the corresponding experimental value. We believe that a 4-quasiparticle band crossing with the 2-quasiparticle band will depress the energies of the states. (authors)

  18. SPARSE FARADAY ROTATION MEASURE SYNTHESIS

    International Nuclear Information System (INIS)

    Andrecut, M.; Stil, J. M.; Taylor, A. R.

    2012-01-01

    Faraday rotation measure synthesis is a method for analyzing multichannel polarized radio emissions, and it has emerged as an important tool in the study of Galactic and extragalactic magnetic fields. The method requires the recovery of the Faraday dispersion function from measurements restricted to limited wavelength ranges, which is an ill-conditioned deconvolution problem. Here, we discuss a recovery method that assumes a sparse approximation of the Faraday dispersion function in an overcomplete dictionary of functions. We discuss the general case when both thin and thick components are included in the model, and we present the implementation of a greedy deconvolution algorithm. We illustrate the method with several numerical simulations that emphasize the effect of the covered range and sampling resolution in the Faraday depth space, and the effect of noise on the observed data.

  19. Rotational propulsion enabled by inertia.

    Science.gov (United States)

    Nadal, François; Pak, On Shun; Zhu, LaiLai; Brandt, Luca; Lauga, Eric

    2014-07-01

    The fluid mechanics of small-scale locomotion has recently attracted considerable attention, due to its importance in cell motility and the design of artificial micro-swimmers for biomedical applications. Most studies on the topic consider the ideal limit of zero Reynolds number. In this paper, we investigate a simple propulsion mechanism --an up-down asymmetric dumbbell rotating about its axis of symmetry-- unable to propel in the absence of inertia in a Newtonian fluid. Inertial forces lead to continuous propulsion for all finite values of the Reynolds number. We study computationally its propulsive characteristics as well as analytically in the small-Reynolds-number limit. We also derive the optimal dumbbell geometry. The direction of propulsion enabled by inertia is opposite to that induced by viscoelasticity.

  20. Single-magnet rotary flowmeter for liquid metals

    OpenAIRE

    Priede, Jānis; Buchenau, Dominique; Gerbeth, Gunter

    2010-01-01

    We present a theory of single-magnet flowmeter for liquid metals and compare it with experimental results. The flowmeter consists of a freely rotating permanent magnet, which is magnetized perpendicularly to the axle it is mounted on. When such a magnet is placed close to a tube carrying liquid metal flow, it rotates so that the driving torque due to the eddy currents induced by the flow is balanced by the braking torque induced by the rotation itself. The equilibrium rotation rate, which var...

  1. Omni rotational driving and steering wheel

    DEFF Research Database (Denmark)

    2008-01-01

    and steering wheel part (108), where the omni rotational part (106) is provided for infinite rotation relative to the flange part (104) by both a drive motor (110) and a steering motor (114) being positionable on the flange part (104), and the driving and steering wheel part (108) is suspended from the upper...... omni rotational part (105) with a suspension (116) such that wheel part (108) can move relatively to the upper omni rotational part (105) in a suspension direction (118), and a reduction gear (120) for gearing the drive torque is provided in the wheel part (108) in order e.g. to assure traction...

  2. Rotation influence on the plasma helical instability

    International Nuclear Information System (INIS)

    Gutkin, T.I.; Tsypin, V.S.; Boleslavskaya, G.I.

    1980-01-01

    The influence of the rotation on helical instability of a plasma with the fixed boundaries (HIFB) is investigated taking into account the compressibility. A case of infinitely long cylinder with distributed current is considered. Cases when a rotating plasma is confined by current magnetic field are analytically considered. It is shown that in the case of the fixed boundary taking into account the compressibility in the HIFB increment increases and the picture of the rotation influence on HIFB considerably changes. Besides, it is shown that in the case of high plasma pressures HIFB can stabilize as a result of the rotation

  3. Instability of counter-rotating stellar disks

    Science.gov (United States)

    Hohlfeld, R. G.; Lovelace, R. V. E.

    2015-09-01

    We use an N-body simulation, constructed using GADGET-2, to investigate an accretion flow onto an astrophysical disk that is in the opposite sense to the disk's rotation. In order to separate dynamics intrinsic to the counter-rotating flow from the impact of the flow onto the disk, we consider an initial condition in which the counter-rotating flow is in an annular region immediately exterior the main portion of the astrophysical disk. Such counter-rotating flows are seen in systems such as NGC 4826 (known as the "Evil Eye Galaxy"). Interaction between the rotating and counter-rotating components is due to two-stream instability in the boundary region. A multi-armed spiral density wave is excited in the astrophysical disk and a density distribution with high azimuthal mode number is excited in the counter-rotating flow. Density fluctuations in the counter-rotating flow aggregate into larger clumps and some of the material in the counter-rotating flow is scattered to large radii. Accretion flow processes such as this are increasingly seen to be of importance in the evolution of multi-component galactic disks.

  4. Forced vibrations of rotating circular cylindrical shells

    International Nuclear Information System (INIS)

    Igawa, Hirotaka; Maruyama, Yoshiyuki; Endo, Mitsuru

    1995-01-01

    Forced vibrations of rotating circular cylindrical shells are investigated. Basic equations, including the effect of initial stress due to rotation, are formulated by the finite-element method. The characteristic relations for finite elements are derived from the energy principle by considering the finite strain. The equations of motion can be separated into quasi-static and dynamic ones, i.e., the equations in the steady rotating state and those in the vibration state. Radial concentrated impulses are considered as the external dynamic force. The transient responses of circular cylindrical shells are numerically calculated under various boundary conditions and rotating speeds. (author)

  5. Self Retaining Anti-Rotation Key

    Science.gov (United States)

    Dixon, Alan Benjamin Christopher (Inventor)

    2015-01-01

    Anti-rotation keys are typically used in applications where an end of a threaded stud is received in a housing, and where the opposite end of the stud projects from the housing to allow attachment of another component to the housing. Once partially received in the housing, further rotation of the stud is prevented by an anti-rotation key. The disclosed anti-rotation key is self-retaining, in that it prevents itself from "backing out" of the channel due to vibration or thermal expansion of the housing, etc., while also being removable from the channel if desired.

  6. The effect of rotations on Michelson interferometers

    Energy Technology Data Exchange (ETDEWEB)

    Maraner, Paolo, E-mail: pmaraner@unibz.it

    2014-11-15

    In the contest of the special theory of relativity, it is shown that uniform rotations induce a phase shift in Michelson interferometers. The effect is second order in the ratio of the interferometer’s speed to the speed of light, further suppressed by the ratio of the interferometer’s arms length to the radius of rotation and depends on the interferometer’s position in the co-rotating frame. The magnitude of the phase shift is just beyond the sensitivity of turntable rotated optical resonators used in present tests of Lorentz invariance. It grows significantly large in Earth’s rotated kilometer-scale Fabry–Perot enhanced interferometric gravitational-wave detectors where it appears as a constant bias. The effect can provide the means of sensing center and radius of rotations. - Highlights: • Rotations induce a phase shift in Michelson interferometers. • Earth’s rotation induces a constant bias in Michelson interferometers. • Michelson interferometers can be used to sense center and radius of rotations.

  7. The effect of rotations on Michelson interferometers

    International Nuclear Information System (INIS)

    Maraner, Paolo

    2014-01-01

    In the contest of the special theory of relativity, it is shown that uniform rotations induce a phase shift in Michelson interferometers. The effect is second order in the ratio of the interferometer’s speed to the speed of light, further suppressed by the ratio of the interferometer’s arms length to the radius of rotation and depends on the interferometer’s position in the co-rotating frame. The magnitude of the phase shift is just beyond the sensitivity of turntable rotated optical resonators used in present tests of Lorentz invariance. It grows significantly large in Earth’s rotated kilometer-scale Fabry–Perot enhanced interferometric gravitational-wave detectors where it appears as a constant bias. The effect can provide the means of sensing center and radius of rotations. - Highlights: • Rotations induce a phase shift in Michelson interferometers. • Earth’s rotation induces a constant bias in Michelson interferometers. • Michelson interferometers can be used to sense center and radius of rotations

  8. Learning Rotation for Kernel Correlation Filter

    KAUST Repository

    Hamdi, Abdullah

    2017-08-11

    Kernel Correlation Filters have shown a very promising scheme for visual tracking in terms of speed and accuracy on several benchmarks. However it suffers from problems that affect its performance like occlusion, rotation and scale change. This paper tries to tackle the problem of rotation by reformulating the optimization problem for learning the correlation filter. This modification (RKCF) includes learning rotation filter that utilizes circulant structure of HOG feature to guesstimate rotation from one frame to another and enhance the detection of KCF. Hence it gains boost in overall accuracy in many of OBT50 detest videos with minimal additional computation.

  9. Electrotherapy modalities for rotator cuff disease.

    Science.gov (United States)

    Page, Matthew J; Green, Sally; Mrocki, Marshall A; Surace, Stephen J; Deitch, Jessica; McBain, Brodwen; Lyttle, Nicolette; Buchbinder, Rachelle

    2016-06-10

    % more). Between-group differences were not important at nine months. No participant reported adverse events.Therapeutic ultrasound produced no clinically important additional benefits when combined with other physical therapy interventions (eight clinically heterogeneous trials, low quality evidence). We are uncertain whether there are differences in patient-important outcomes between ultrasound and other active interventions (manual therapy, acupuncture, glucocorticoid injection, glucocorticoid injection plus oral tolmetin sodium, or exercise) because the quality of evidence is very low. Two placebo-controlled trials reported results favouring LLLT up to three weeks (low quality evidence), however combining LLLT with other physical therapy interventions produced few additional benefits (10 clinically heterogeneous trials, low quality evidence). We are uncertain whether transcutaneous electrical nerve stimulation (TENS) is more or less effective than glucocorticoid injection with respect to pain, function, global treatment success and active range of motion because of the very low quality evidence from a single trial. In other single, small trials, no clinically important benefits of pulsed electromagnetic field therapy (PEMF), microcurrent electrical stimulation (MENS), acetic acid iontophoresis and microwave diathermy were observed (low or very low quality evidence).No adverse events of therapeutic ultrasound, LLLT, TENS or microwave diathermy were reported by any participants. Adverse events were not measured in any trials investigating the effects of PEMF, MENS or acetic acid iontophoresis. Based on low quality evidence, therapeutic ultrasound may have short-term benefits over placebo in people with calcific tendinitis, and LLLT may have short-term benefits over placebo in people with rotator cuff disease. Further high quality placebo-controlled trials are needed to confirm these results. In contrast, based on low quality evidence, PEMF may not provide clinically

  10. Modeling of Prosthetic Limb Rotation Control by Sensing Rotation of Residual Arm Bone

    OpenAIRE

    Li, Guanglin; Kuiken, Todd A.

    2008-01-01

    We proposed a new approach to improve the control of prosthetic arm rotation in amputees. Arm rotation is sensed by implanting a small permanent magnet into the distal end of the residual bone, which produces a magnetic field. The position of the bone rotation can be derived from magnetic field distribution detected with magnetic sensors on the arm surface, and then conveyed to the prosthesis controller to manipulate the rotation of the prosthesis. Proprioception remains intact for residual l...

  11. A novel rotating disk electrode cell design; The inverted rotating disk electrode

    Energy Technology Data Exchange (ETDEWEB)

    Zdunek, A.D.; Selman, J.R. (Illinois Inst. of Tech., Chicago, IL (United States). Dept. of Chemical Engineering)

    1992-09-01

    In this paper a new cell configuration for use with the rotating disk electrode (RDE), the inverted rotating disk electrode (IRDE), is outlined. The IRDE faces upwards in solution and rotates without electrolyte leakage, even in highly corrosive solutions. This facilitates gas evolution and free convection studies. Mass transfer characteristics obtained by limiting current measurements agree well with literature for the RDE.

  12. State-to-state differential cross sections for rotationally inelastic scattering of Na2 by He

    International Nuclear Information System (INIS)

    Bergmann, K.; Hefter, U.; Witt, J.

    1980-01-01

    State-to-state differential cross sections for rotational transitions of Na 2 in collisions with He are measured in the electronic and vibrational ground state at thermal collision energies using a new laser technique. Single rotational levels j/sub i/ are labelled by modulation of their population via laser optical pumping using a dye laser. The modulation of the fluorescence induced by an Ar + laser tuned to the level j/sub f/=28 is proportional to the cross section for collisional transfer j/sub i/→j/sub f/ and is detected at the scattering angle theta. A single optical fiber and a fiber bundle provide a flexible connection between the detector and the laser and photomultiplier, respectively. Transitions as large as Δj=20 are observed. At small angles elastic scattering is dominant, but rotationally inelastic processes become increasingly important at larger scattering angles. Rotational rainbow structure causing a steep onset of the cross section with the scattering angle theta (at fixed Δj) or a sharp cutoff with Δj (at fixed theta) is found. Preliminary results on rotational energy transfer in v=1 indicates that vibrational motion of the molecule favors larger rotational quantum jumps. semiclassical picture for the scattering of a hard ellipsoid gives a

  13. Polygons on a rotating fluid surface

    DEFF Research Database (Denmark)

    Jansson, Thomas R.N.; Haspang, Martin P.; Jensen, Kåre H.

    2006-01-01

    We report a novel and spectacular instability of a fluid surface in a rotating system. In a flow driven by rotating the bottom plate of a partially filled, stationary cylindrical container, the shape of the free surface can spontaneously break the axial symmetry and assume the form of a polygon r...

  14. Rotational glitches in radio pulsars and magnetars

    NARCIS (Netherlands)

    Antonopoulou, D.

    2015-01-01

    Neutron stars are the most compact known stars; their cores are of higher density than an atomic nucleus. Their rotation rates are generally very predictable, with a slow decrease over time. This spin-down is occasionally interrupted, however, by abrupt 'glitches' when the rotation rate increases

  15. Glueballs as rotating folded closed strings

    Science.gov (United States)

    Sonnenschein, Jacob; Weissman, Dorin

    2015-12-01

    In previous papers [1, 2] we argued that mesons and baryons can be described as rotating open strings in holographic backgrounds. Now we turn to closed strings, which should be the duals of glueballs. We look at the rotating folded closed string in both flat and curved backgrounds.

  16. On generating counter-rotating streamwise vortices

    KAUST Repository

    Winoto, S H

    2015-09-23

    Counter-rotating streamwise vortices are known to enhance the heat transfer rate from a surface and also to improve the aerodynamic performance of an aerofoil. In this paper, some methods to generate such counter-rotating vortices using different methods or physical conditions will be briefly considered and discussed.

  17. Testing the egocentric mirror-rotation hypothesis.

    Science.gov (United States)

    Muelenz, Cornelius; Hecht, Heiko; Gamer, Matthias

    2010-01-01

    Although observers know about the law of reflection, their intuitive understanding of spatial locations in mirrors is often erroneous. Hecht et al. (2005) proposed a two-stage mirror-rotation hypothesis to explain these misconceptions. The hypothesis involves an egocentric bias to the effect that observers behave as if the mirror surface were rotated by about 2 degrees to be more orthogonal than is the case. We test four variants of the hypothesis, which differ depending on whether the virtual world, the mirror, or both are taken to be rotated. We devised an experimental setup that allowed us to distinguish between these variants. Our results confirm that the virtual world--and only the virtual world--is being rotated. Observers had to perform a localization task, using a mirror that was either fronto-parallel or rotated opposite the direction of the predicted effect. We were thus able to compensate for the effect. The positions of objects in mirrors were perceived in accordance with the erroneous conception that the virtual world behind the mirror is slightly rotated and that the reconstruction is based on the non-rotated fronto-parallel mirror. A covert rotation of the mirror by about 2 degrees against the predicted effect was able to compensate for the placement error.

  18. Identifying Broadband Rotational Spectra with Neural Networks

    Science.gov (United States)

    Zaleski, Daniel P.; Prozument, Kirill

    2017-06-01

    A typical broadband rotational spectrum may contain several thousand observable transitions, spanning many species. Identifying the individual spectra, particularly when the dynamic range reaches 1,000:1 or even 10,000:1, can be challenging. One approach is to apply automated fitting routines. In this approach, combinations of 3 transitions can be created to form a "triple", which allows fitting of the A, B, and C rotational constants in a Watson-type Hamiltonian. On a standard desktop computer, with a target molecule of interest, a typical AUTOFIT routine takes 2-12 hours depending on the spectral density. A new approach is to utilize machine learning to train a computer to recognize the patterns (frequency spacing and relative intensities) inherit in rotational spectra and to identify the individual spectra in a raw broadband rotational spectrum. Here, recurrent neural networks have been trained to identify different types of rotational spectra and classify them accordingly. Furthermore, early results in applying convolutional neural networks for spectral object recognition in broadband rotational spectra appear promising. Perez et al. "Broadband Fourier transform rotational spectroscopy for structure determination: The water heptamer." Chem. Phys. Lett., 2013, 571, 1-15. Seifert et al. "AUTOFIT, an Automated Fitting Tool for Broadband Rotational Spectra, and Applications to 1-Hexanal." J. Mol. Spectrosc., 2015, 312, 13-21. Bishop. "Neural networks for pattern recognition." Oxford university press, 1995.

  19. 14 CFR 33.74 - Continued rotation.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Continued rotation. 33.74 Section 33.74 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: AIRCRAFT ENGINES Design and Construction; Turbine Aircraft Engines § 33.74 Continued rotation. If...

  20. A rotational integral formula for intrinsic volumes

    DEFF Research Database (Denmark)

    Jensen, Eva Bjørn Vedel; Rataj, J.

    2008-01-01

    A rotational version of the famous Crofton formula is derived. The motivation for deriving the formula comes from local stereology, a new branch of stereology based on sections through fixed reference points. The formula shows how rotational averages of intrinsic volumes measured on sections...

  1. Rotational properties of strange-pulsar models

    International Nuclear Information System (INIS)

    Benvenuto, O.G.; Horvath, J.E.; Vucetich, H.

    1991-01-01

    We present a study of the rotational properties of strange pulsars: strange-matter stars capable of supporting glitches. It is shown that their differentiated internal structure implies a lower maximum rotational frequency than that of homogeneous strange stars. Nevertheless, they are able to fit the known pulsar properties

  2. Tutorial on earthquake rotational effects: historical examples

    Czech Academy of Sciences Publication Activity Database

    Kozák, Jan

    2009-01-01

    Roč. 99, 2B (2009), s. 998-1010 ISSN 0037-1106 Institutional research plan: CEZ:AV0Z30120515 Keywords : rotational seismic models * earthquake rotational effects * historical earthquakes Subject RIV: DC - Siesmology, Volcanology, Earth Structure Impact factor: 1.860, year: 2009

  3. Orbital Mechanics near a Rotating Asteroid

    Indian Academy of Sciences (India)

    2016-01-27

    Jan 27, 2016 ... This study investigates the different novel forms of the dynamical equations of a particle orbiting a rotating asteroid and the effective potential, the Jacobi integral, etc. on different manifolds. Nine new forms of the dynamical equations of a particle orbiting a rotating asteroid are presented, and the classical ...

  4. Rotational hysteresis measurements on alumite perpendicular media

    NARCIS (Netherlands)

    van Drent, W.P.; van Drent, W.P.; Sterringa, E.R.; Sterringa, E.R.; Lodder, J.C.; Bottoni, G.; Candolfo, D.; Cecchetti, A.; Masoli, F.

    1991-01-01

    Rotational hysteresis energy loss measurements have been performed to support the analysis of the magnetization processes of Fe- and Co-alumite perpendicular recording media. Two measurement techniques gave comparable results within error limits. The rotational hysteresis integral is severly lowered

  5. Rotational image deblurring with sparse matrices

    DEFF Research Database (Denmark)

    Hansen, Per Christian; Nagy, James G.; Tigkos, Konstantinos

    2014-01-01

    We describe iterative deblurring algorithms that can handle blur caused by a rotation along an arbitrary axis (including the common case of pure rotation). Our algorithms use a sparse-matrix representation of the blurring operation, which allows us to easily handle several different boundary...

  6. Treatment alternative for irreparable rotator cuff ruptures ...

    African Journals Online (AJOL)

    Background: The treatment of massive irreparable rotator cuff rupture has still no consensus among shoulder surgeons. It is assumed that symptomatic rotator cuff tendon rupture is accepted as irreparable if retraction amount of tendon is Patte stage 3 on MRI; degree of fatty atrophy is Goutallier stage 3 or 4; narrowing of ...

  7. Aryabhata and Axial Rotation of Earth

    Indian Academy of Sciences (India)

    GENERAL I ARTICLE. Aryabhata and Axial Rotation of Earth. 3. A Brief History. Amartya Kumar Datta is in the Stat-Math Unit of. Indian Statistic.llnstiutte,. Kolkata. His research ... historical account of some of Aryabha~a's views on axial rotation of Earth, ..... and stress on periodic observations and updating of the parameters.

  8. Electropumping of water with rotating electric fields

    DEFF Research Database (Denmark)

    Hansen, Jesper Schmidt; De Luca, Sergio; Todd, Billy

    2013-01-01

    exploiting the coupling of spin angular momentum to linear streaming momentum. A spatially uniform rotating electric field is applied to water molecules, which couples to their permanent electric dipole moments. The resulting molecular rotational momentum is converted into linear streaming momentum...

  9. Numerical study of rotating relativistic stars

    International Nuclear Information System (INIS)

    Wilson, J.R.

    1975-01-01

    The equations of structure for rotating stars in general relativity are presented and put in a form suitable for computer calculations. The results of equilibrium calculations for supermassive stars, neutron stars, and magnetically supported stars are reported, as are calculations of collapsing, rotating, and magnetized stars in the slowly changing gravitational field approximation. (auth)

  10. Design of a piezoelectric rotation actuator

    NARCIS (Netherlands)

    Holterman, J.; de Vries, Theodorus J.A.; Babakhani, B.; Brouwer, Dannis Michel

    2012-01-01

    In order to facilitate active damping within a linear motion system, a self-sensing piezoelectric rotation actuator has been designed. The rotation actuator consists of two piezoelectric stacks that function as linear actuators, embedded in a mechanical interface with several elastic elements, thus

  11. Regolith on Super Fast Rotators

    Science.gov (United States)

    Sanchez Lana, Diego Paul; Scheeres, Daniel J.

    2017-10-01

    The current understanding of small asteroids in the Solar System is that they are gravitational aggregates held together by gravitational, cohesive and adhesive forces. Results from the Hayabusa mission to Itokawa along with in situ, thermal and radar observations of asteroids have shown that they can be covered in a size distribution of grains that spans from microns to tens of meters. Before the Hayabusa mission, it was generally thought that smaller asteroids would likely be “regolith-free,” due to impact seismic shaking removing the loose covering. Given the regolith-rich surface of that body, it is now an open question whether even smaller bodies, down to a few meters in size, could also retain regolith covering. The question is especially compelling for the small-fast rotators, whose surface centripetal accelerations exceed their gravitational attraction. When the physical theory of cohesion is considered, it becomes possible for small-fast rotators to retain regolith.We use a Soft-Sphere discrete element method (SSDEM) code to simulate a longitudinal slice of a spherical monolith covered by cohesive regolith. The simulations are carried out in the body frame. Tensile strength is varied to span the observed strength of asteroids and spin rate is elevated in small steps until the majority of regolith is removed from the surface. The simulations show that under an increasing spin rate (such as due to the YORP effect), the regolith covering on an otherwise monolithic asteroid is preferentially lost across certain regions of the body. In general, regolith from the mid latitudes is the first to fail at high spin rates. This failure happens either by regolith flowing towards the equator or by detachment of large coherent chunks of material depending on the tensile strength of the regolith. Regolith from the equator region fails next, usually by the detachment of large pieces. Regolith from the poles stays in place unless the spin rates are extremely high. With

  12. Vector correlations in rotationally inelastic molecular collisions

    Energy Technology Data Exchange (ETDEWEB)

    Lemeshko, Mikhail

    2011-04-13

    diffractive part of the scattering amplitude which is governed by a single Legendre moment characterizing the anisotropy of the hard-core part of the system's potential energy surface. The alignment moments obtained for He-OH(X{sup 2}{pi}), He-O{sub 2}(X{sup 3}{sigma}), and He-CaH(X{sup 2}{sigma}) allowed to identify the fingerprints of diffraction, which can be used to discern diffraction-driven stereodynamics in future experiments and exact computations. Analytic results for the Ne-NO(A{sup 2}{sigma}) system were found to be in good agreement with experiment and exact computations for low rotational energy transfer; the discrepancy found for higher excitation channels could be traced back to the breakdown of the sudden approximation. The model was also applied to the k-j-k{sup '} and k-j-k{sup '}-j{sup '} correlations in rotationally inelastic Ar-NO(X{sup 2}{pi}) scattering. It was shown that preparing the reagents with polarized angular momentum j makes it possible to significantly alter the collision dynamics and stereodynamics. In the final part of the thesis the analytic theory was extended to the study of multiple scattering of matter waves propagating through atomic and molecular gases. The combination of the Fraunhofer model with the semiclassical approximation to account, respectively, for the repulsive and attractive part of the potential energy surface resulted in a simple analytic formula, which agree well with experiment for the refraction of a Li beam passing through Xe gas. (orig.)

  13. Vector correlations in rotationally inelastic molecular collisions

    International Nuclear Information System (INIS)

    Lemeshko, Mikhail

    2011-01-01

    The thesis presents an analytic model that describes scalar and vector properties of molecular collisions, both field-free and in fields. The model is based on the sudden approximation and treats molecular scattering as the Fraunhofer diffraction of matter waves from the hard-core part of the interaction potential. The theory has no fitting parameters and is inherently quantum, rendering fully state- and energy-resolved scattering amplitudes and all the quantities that unfold from them in analytic form. This allows to obtain complex polarization moments inherent to quantum stereodynamics, and to account for interference and other non-classical effects. The simplicity and analyticity of the model paves a way to understanding the origin of the features observed in experiment and exact computations, such as the angular oscillations in the state-to-state differential cross sections and the polarization moments, the rotational-state dependent variation of the integral cross sections, and change of these quantities as a function of the applied field. The theory was applied to study the k - k ' vector correlation (differential cross section) for the following collision systems: Ar-NO(X 2 Π) and Ne-OCS(X 1 Σ) in an electrostatic field, Na + -N 2 (X 1 Σ) in a laser field, and He-CaH( 2 Σ), He-O 2 (X 3 Σ), and He-OH(X 2 Π) in a magnetic field. The model was able to reproduce the behavior of the differential cross sections and their variation with field strength. Combining the Fraunhofer model with the quantum theory of vector correlations made it possible to study three- and four-vector properties. The model results for the k-k ' -j ' vector correlation in Ar-NO(X 2 Π) and He-NO(X 2 Π) scattering were found to be in good agreement with experiment and exact computations. This allowed to demonstrate that the stereodynamics of such collisions is contained solely in the diffractive part of the scattering amplitude which is governed by a single Legendre moment

  14. Paddle-based rotating-shield brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Yunlong; Xu, Weiyu [Department of Electrical and Computer Engineering, University of Iowa, 4016 Seamans Center, Iowa City, Iowa 52242 (United States); Flynn, Ryan T.; Kim, Yusung; Bhatia, Sudershan K.; Buatti, John M. [Department of Radiation Oncology, University of Iowa, 200 Hawkins Drive, Iowa City, Iowa 52242 (United States); Dadkhah, Hossein [Department of Biomedical Engineering, University of Iowa, 1402 Seamans Center, Iowa City, Iowa 52242 (United States); Wu, Xiaodong, E-mail: xiaodong-wu@uiowa.edu [Department of Electrical and Computer Engineering, University of Iowa, 4016 Seamans Center, Iowa City, Iowa 52242 and Department of Radiation Oncology, University of Iowa, 200 Hawkins Drive, Iowa City, Iowa 52242 (United States)

    2015-10-15

    Purpose: The authors present a novel paddle-based rotating-shield brachytherapy (P-RSBT) method, whose radiation-attenuating shields are formed with a multileaf collimator (MLC), consisting of retractable paddles, to achieve intensity modulation in high-dose-rate brachytherapy. Methods: Five cervical cancer patients using an intrauterine tandem applicator were considered to assess the potential benefit of the P-RSBT method. The P-RSBT source used was a 50 kV electronic brachytherapy source (Xoft Axxent™). The paddles can be retracted independently to form multiple emission windows around the source for radiation delivery. The MLC was assumed to be rotatable. P-RSBT treatment plans were generated using the asymmetric dose–volume optimization with smoothness control method [Liu et al., Med. Phys. 41(11), 111709 (11pp.) (2014)] with a delivery time constraint, different paddle sizes, and different rotation strides. The number of treatment fractions (fx) was assumed to be five. As brachytherapy is delivered as a boost for cervical cancer, the dose distribution for each case includes the dose from external beam radiotherapy as well, which is 45 Gy in 25 fx. The high-risk clinical target volume (HR-CTV) doses were escalated until the minimum dose to the hottest 2 cm{sup 3} (D{sub 2cm{sup 3}}) of either the rectum, sigmoid colon, or bladder reached their tolerance doses of 75, 75, and 90 Gy{sub 3}, respectively, expressed as equivalent doses in 2 Gy fractions (EQD2 with α/β = 3 Gy). Results: P-RSBT outperformed the two other RSBT delivery techniques, single-shield RSBT (S-RSBT) and dynamic-shield RSBT (D-RSBT), with a properly selected paddle size. If the paddle size was angled at 60°, the average D{sub 90} increases for the delivery plans by P-RSBT on the five cases, compared to S-RSBT, were 2.2, 8.3, 12.6, 11.9, and 9.1 Gy{sub 10}, respectively, with delivery times of 10, 15, 20, 25, and 30 min/fx. The increases in HR-CTV D{sub 90}, compared to D-RSBT, were 16

  15. Influence of toroidal rotation on tearing modes

    Science.gov (United States)

    Cai, Huishan; Cao, Jintao; Li, Ding

    2017-10-01

    Tearing modes stability analysis including toroidal rotation is studied. It is found that rotation affects the stability of tearing modes mainly through the interaction with resistive inner region of tearing mode. The coupling of magnetic curvature with centrifugal force and Coriolis force provides a perturbed perpendicular current, and a return parallel current is induced to affect the stability of tearing modes. Toroidal rotation plays a stable role, which depends on the magnitude of Mach number and adiabatic index Γ, and is independent on the direction of toroidal rotation. For Γ >1, the scaling of growth rate is changed for typical Mach number in present tokamaks. For Γ = 1 , the scaling keeps unchanged, and the effect of toroidal rotation is much less significant, compared with that for Γ >1. National Magnetic Confinement Fusion Science Program and National Science Foundation of China under Grants No. 2014GB106004, No. 2013GB111000, No. 11375189, No. 11075161 and No. 11275260, and Youth Innovation Promotion Association CAS.

  16. Shadow of rotating wormhole in plasma environment

    Science.gov (United States)

    Abdujabbarov, Ahmadjon; Juraev, Bakhtinur; Ahmedov, Bobomurat; Stuchlík, Zdeněk

    2016-07-01

    The massless particle motion around rotating wormhole in the presence of plasma environment has been studied. It has been shown that the presence of the plasma decreases the inner radius of the circular orbits of photons around rotating wormhole. The shadow cast by rotating wormhole surrounded by inhomogeneous plasma with the radial power-law density has been explored. It has been shown that the shape and size of the wormhole shadow is distorted and changed depending on i) plasma parameters, ii) wormhole rotation and iii) inclination angle between observer plane and axis of rotation of wormhole. As an example we have considered an inverse radial distribution of the plasma density and different types of the wormhole solution.

  17. An on/off resonance rotating frame relaxation experiment to monitor millisecond to microsecond timescale dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Seho; Baum, Jean [Rutgers University, Department of Chemistry and Chemical Biology (United States)], E-mail: baum@rutchem.rutgers.edu

    2004-10-15

    Rotating frame relaxation experiments in proteins are used to study slow motions on the microsecond to millisecond timescale. An on/off resonance rotating frame relaxation experiment (R{sub 1{rho}}) has been developed that incorporates adiabatic rotations into a R{sub 1{rho}}-R{sub 1} constant relaxation time experiment with weak radio frequency field strengths in order to effectively lock the magnetization over a wide range of {sup 15}N frequencies. The new pulse sequence allows the measurement of a wide range of chemical exchange timescales on the order of 1.0 to 0.05 ms over an asymmetric bandwidth from +1.7{omega}{sub 1} to -0.5{omega}{sub 1} in a single experiment. A total bandwidth of {+-}1.7{omega}{sub 1} is obtained by performing the experiment a second time with a reversed adiabatic rotation.

  18. Non-Contact Translation-Rotation Sensor Using Combined Effects of Magnetostriction and Piezoelectricity

    Directory of Open Access Journals (Sweden)

    Guang Meng

    2012-10-01

    Full Text Available Precise displacement sensors are an important topic in precision engineering. At present, this type of sensors typically have a single feature of either translation or rotation measurement. They are also inconvenient to integrate with the host devices. In this report we propose a new kind of sensor that enables both translation and rotation measurement by using the combined effect of magnetostriction and piezoelectricity. As a proof of concept, we experimentally realized a prototype of non-contact translation-rotation precise sensor. In the current research stage, through both theoretical and experimental study, the non-contact displacement sensor is shown to be feasible for measuring both translation and rotation either in coarse or fine measurement. Moreover, owing to its compact, rigid structure and fewer components, it can be easily embedded in host equipment.

  19. Non-contact translation-rotation sensor using combined effects of magnetostriction and piezoelectricity.

    Science.gov (United States)

    Yang, Bintang; Liu, Qingwei; Zhang, Ting; Cao, Yudong; Feng, Zhiqiang; Meng, Guang

    2012-10-15

    Precise displacement sensors are an important topic in precision engineering. At present, this type of sensors typically have a single feature of either translation or rotation measurement. They are also inconvenient to integrate with the host devices. In this report we propose a new kind of sensor that enables both translation and rotation measurement by using the combined effect of magnetostriction and piezoelectricity. As a proof of concept, we experimentally realized a prototype of non-contact translation-rotation precise sensor. In the current research stage, through both theoretical and experimental study, the non-contact displacement sensor is shown to be feasible for measuring both translation and rotation either in coarse or fine measurement. Moreover, owing to its compact, rigid structure and fewer components, it can be easily embedded in host equipment.

  20. Ultra-compact polarization rotation in integrated silicon photonics using digital metamaterials.

    Science.gov (United States)

    Majumder, Apratim; Shen, Bing; Polson, Randy; Menon, Rajesh

    2017-08-21

    Polarization controlling devices such as polarization splitters and rotators are critical elements in integrated-photonic circuits that function via polarization-diversity schemes. Here, we present the design of an ultra-compact nanophotonic-polarization rotator (NPR) that rotates the polarization state from TE to TM with a simulated extinction ratio of 23dB over a coupling length of 5µm and an operating bandwidth of 40nm. This all-silicon device can be fabricated in a single lithography step and we have fabricated and characterized a preliminary device exhibiting 9dB extinction ratio. To emphasize the generality of our methodology, we also designed a NPR that can rotate the polarization state from TM to TE as well. A small device footprint is enabled by the evanescent coupling of guided modes enabled by computationally designed digital metamaterials.

  1. AUDITOR ROTATION - A CRITICAL AND COMPARATIVE ANALYSIS

    Directory of Open Access Journals (Sweden)

    Mocanu Mihaela

    2011-12-01

    Full Text Available The present paper starts out from the challenge regarding auditor tenure launched in 2010 by the Green Paper of the European Commission Audit Policy: Lessons from the Crisis. According to this document, the European Commission speaks both in favor of the mandatory rotation of the audit firm, and in favor of the mandatory rotation of audit partners. Rotation is considered a solution to mitigate threats to independence generated by familiarity, intimidation and self-interest in the context of a long-term audit-client relationship. At international level, there are several studies on auditor rotation, both empirical (e.g. Lu and Sivaramakrishnan, 2009, Li, 2010, Kaplan and Mauldin, 2008, Jackson et al., 2008 and normative in nature (e.g. Marten et al., 2007, Muller, 2006 and Gelter, 2004. The objective of the present paper is to perform a critical and comparative analysis of the regulations on internal and external rotation in force at international level, in the European Union and in the United States of America. Moreover, arguments both in favor and against mandatory rotation are brought into discussion. With regard to the research design, the paper has a normative approach. The main findings are first of all that by comparison, all regulatory authorities require internal rotation at least in the case of public interest entities, while the external rotation is not in the focus of the regulators. In general, the most strict and detailed requirements are those issued by the Securities and Exchange Commission from the United States of America. Second of all, in favor of mandatory rotation speaks the fact that the auditor becomes less resilient in case of divergence of opinions between him and company management, less stimulated to follow his own interest, and more scrupulous in conducting the audit. However, mandatory rotation may also have negative consequences, thus the debate on the opportunity of this regulatory measure remains open-ended.

  2. Synchronous states of slowly rotating pendula

    Energy Technology Data Exchange (ETDEWEB)

    Kapitaniak, Marcin [Division of Dynamics, Technical University of Lodz, Stefanowskiego 1/15, 90-924 Lodz (Poland); Centre for Applied Dynamics Research, School of Engineering, University of Aberdeen, AB24 3UE Aberdeen, Scotland (United Kingdom); Czolczynski, Krzysztof; Perlikowski, Przemysław; Stefanski, Andrzej [Division of Dynamics, Technical University of Lodz, Stefanowskiego 1/15, 90-924 Lodz (Poland); Kapitaniak, Tomasz, E-mail: tomasz.kapitaniak@p.lodz.pl [Division of Dynamics, Technical University of Lodz, Stefanowskiego 1/15, 90-924 Lodz (Poland)

    2014-08-01

    Coupled systems that contain rotating elements are typical in physical, biological and engineering applications and for years have been the subject of intensive studies. One problem of scientific interest, which among others occurs in such systems is the phenomenon of synchronization of different rotating parts. Despite different initial conditions, after a sufficiently long transient, the rotating parts move in the same way — complete synchronization, or a permanent constant shift is established between their displacements, i.e., the angles of rotation — phase synchronization. Synchronization occurs due to dependence of the periods of rotating elements motion and the displacement of the base on which these elements are mounted. We review the studies on the synchronization of rotating pendula and compare them with the results obtained for oscillating pendula. As an example we consider the dynamics of the system consisting of n pendula mounted on the movable beam. The pendula are excited by the external torques which are inversely proportional to the angular velocities of the pendula. As the result of such excitation each pendulum rotates around its axis of rotation. It has been assumed that all pendula rotate in the same direction or in the opposite directions. We consider the case of slowly rotating pendula and estimate the influence of the gravity on their motion. We classify the synchronous states of the identical pendula and observe how the parameters mismatch can influence them. We give evidence that synchronous states are robust as they exist in the wide range of system parameters and can be observed in a simple experiment.

  3. Synchronous states of slowly rotating pendula

    International Nuclear Information System (INIS)

    Kapitaniak, Marcin; Czolczynski, Krzysztof; Perlikowski, Przemysław; Stefanski, Andrzej; Kapitaniak, Tomasz

    2014-01-01

    Coupled systems that contain rotating elements are typical in physical, biological and engineering applications and for years have been the subject of intensive studies. One problem of scientific interest, which among others occurs in such systems is the phenomenon of synchronization of different rotating parts. Despite different initial conditions, after a sufficiently long transient, the rotating parts move in the same way — complete synchronization, or a permanent constant shift is established between their displacements, i.e., the angles of rotation — phase synchronization. Synchronization occurs due to dependence of the periods of rotating elements motion and the displacement of the base on which these elements are mounted. We review the studies on the synchronization of rotating pendula and compare them with the results obtained for oscillating pendula. As an example we consider the dynamics of the system consisting of n pendula mounted on the movable beam. The pendula are excited by the external torques which are inversely proportional to the angular velocities of the pendula. As the result of such excitation each pendulum rotates around its axis of rotation. It has been assumed that all pendula rotate in the same direction or in the opposite directions. We consider the case of slowly rotating pendula and estimate the influence of the gravity on their motion. We classify the synchronous states of the identical pendula and observe how the parameters mismatch can influence them. We give evidence that synchronous states are robust as they exist in the wide range of system parameters and can be observed in a simple experiment

  4. Preliminary Results of a Consecutive Series of Large & Massive Rotator Cuff Tears Treated with Arthroscopic Rotator Cuff Repairs Augmented with Extracellular Matrix

    Directory of Open Access Journals (Sweden)

    Paolo Consigliere

    2017-01-01

    Full Text Available Background: Recurrence rate of rotator cuff tears is still high despite the improvements of surgical techniques, materials used and a better knowledge of the healing process of the rotator cuff tendons. Large to massive rotator cuff tears are particularly associated with a high failure rate, especially in elderly. Augmentation of rotator cuff repairs with extracellular matrix or synthetic patches has gained popularity in recent years with the aim of reducing failure.The aim of this study was to investigate the outcome of rotator cuff repairs augmented with denatured extracellular matrix in a series of patients who underwent arthroscopic rotator cuff repair for large to massive tears.Methods: Ten consecutive patients, undergoing arthroscopic rotator cuff repair with extracellular matrix augment for large and massive tears, were prospectively enrolled into this single surgeon study. All repairs were performed arthroscopically with a double row technique augmented with extracellular matrix. Oxford Shoulder Score, Constant Score and pain visual analogue scale (VAS were used to monitor the shoulder function and outcome pre-operatively and at three, six and 12-month follow-up. Minimum follow up was tree months. Mean follow up was 7 months.Results: Mean Constant score improved from 53 (SD=4 pre-operatively to 75 (SD=11 at final follow up. Mean Oxford score also increased from 30 (SD=8 pre-operatively to 47 (SD=10 at the final follow up. The visual analogue scale (VAS improved from seven out of 10 (SD=2 preoperatively to 0.6 (SD=0.8 at final follow up. Additionally, there was significant improvement at three months mark in Constant score. Conclusion: Arthroscopic repair and augmentation of large and massive rotator cuff tears with extracellular matrix patch has good early outcome.

  5. Rotational Invariant Dimensionality Reduction Algorithms.

    Science.gov (United States)

    Lai, Zhihui; Xu, Yong; Yang, Jian; Shen, Linlin; Zhang, David

    2017-11-01

    A common intrinsic limitation of the traditional subspace learning methods is the sensitivity to the outliers and the image variations of the object since they use the norm as the metric. In this paper, a series of methods based on the -norm are proposed for linear dimensionality reduction. Since the -norm based objective function is robust to the image variations, the proposed algorithms can perform robust image feature extraction for classification. We use different ideas to design different algorithms and obtain a unified rotational invariant (RI) dimensionality reduction framework, which extends the well-known graph embedding algorithm framework to a more generalized form. We provide the comprehensive analyses to show the essential properties of the proposed algorithm framework. This paper indicates that the optimization problems have global optimal solutions when all the orthogonal projections of the data space are computed and used. Experimental results on popular image datasets indicate that the proposed RI dimensionality reduction algorithms can obtain competitive performance compared with the previous norm based subspace learning algorithms.

  6. Random motion and Brownian rotation

    International Nuclear Information System (INIS)

    Wyllie, G.

    1980-01-01

    The course is centred on the Brownian motion - the random movement of molecules arising from thermal fluctuations of the surrounding medium - and starts with the classical theory of A. Einstein, M.v. Smoluchowski and P. Langevin. The first part of this article is quite elementary, and several of the questions raised in it have been instructively treated in a much more sophisticated way in recent reviews by Pomeau and Resibois and by Fox. This simple material may nevertheless be helpful to some readers whose main interest lies in approaching the work on Brownian rotation reviewed in the latter part of the present article. The simplest, and most brutally idealised, problem in our field of interest is that of the random walk in one dimension of space. Its solution leads on, through the diffusivity-mobility relation of Einstein, to Langevin's treatment of the Brownian motion. The application of these ideas to the movement of a molecule in a medium of similar molecules is clearly unrealistic, and much energy has been devoted to finding a suitable generalisation. We shall discuss in particular ideas due to Green, Zwanzig and Mori. (orig./WL)

  7. Multi-method automated diagnostics of rotating machines

    Science.gov (United States)

    Kostyukov, A. V.; Boychenko, S. N.; Shchelkanov, A. V.; Burda, E. A.

    2017-08-01

    The automated machinery diagnostics and monitoring systems utilized within the petrochemical plants are an integral part of the measures taken to ensure safety and, as a consequence, the efficiency of these industrial facilities. Such systems are often limited in their functionality due to the specifics of the diagnostic techniques adopted. As the diagnostic techniques applied in each system are limited, and machinery defects can have different physical nature, it becomes necessary to combine several diagnostics and monitoring systems to control various machinery components. Such an approach is inconvenient, since it requires additional measures to bring the diagnostic results in a single view of the technical condition of production assets. In this case, we mean by a production facility a bonded complex of a process unit, a drive, a power source and lines. A failure of any of these components will cause an outage of the production asset, which is unacceptable. The purpose of the study is to test a combined use of vibration diagnostics and partial discharge techniques within the diagnostic systems of enterprises for automated control of the technical condition of rotating machinery during maintenance and at production facilities. The described solutions allow you to control the condition of mechanical and electrical components of rotating machines. It is shown that the functionality of the diagnostics systems can be expanded with minimal changes in technological chains of repair and operation of rotating machinery. Automation of such systems reduces the influence of the human factor on the quality of repair and diagnostics of the machinery.

  8. Designing safer composite helmets to reduce rotational accelerations during oblique impacts.

    Science.gov (United States)

    Mosleh, Yasmine; Cajka, Martin; Depreitere, Bart; Vander Sloten, Jos; Ivens, Jan

    2018-03-01

    Oblique impact is the most common accident situation that occupants in traffic accidents or athletes in professional sports experience. During oblique impact, the human head is subjected to a combination of linear and rotational accelerations. Rotational movement is known to be responsible for traumatic brain injuries. In this article, composite foam with a column/matrix composite configuration is proposed for head protection applications to replace single-layer uniform foam, to better attenuate rotational movement of the head during oblique impacts. The ability of composite foam in the mitigation of rotational head movement is studied by performing finite element (FE) simulations of oblique impact on flat and helmet shape specimens. The performance of composite foam with respect to parameters such as compliance of the matrix foam and the number, size and cross-sectional shape of the foam columns is explored in detail, and subsequently an optimized structure is proposed. The simulation results show that using composite foam instead of single-layer foam, the rotational acceleration and velocity of the headform can be significantly reduced. The parametric study indicates that using a more compliant matrix foam and by increasing the number of columns in the composite foam configuration, the rotation can be further mitigated. This was confirmed by experimental results. The simulation results were also analyzed based on global head injury criteria such as head injury criterion, rotational injury criterion, brain injury criterion and generalized acceleration model for brain injury threshold which further confirmed the superior performance of composite foam versus single-layer homogeneous expanded polystyrene foam. The findings of simulations give invaluable information for design of protective helmets or, for instance, headliners for the automotive industry.

  9. Speed of recovery after arthroscopic rotator cuff repair.

    Science.gov (United States)

    Kurowicki, Jennifer; Berglund, Derek D; Momoh, Enesi; Disla, Shanell; Horn, Brandon; Giveans, M Russell; Levy, Jonathan C

    2017-07-01

    The purpose of this study was to delineate the time taken to achieve maximum improvement (plateau of recovery) and the degree of recovery observed at various time points (speed of recovery) for pain and function after arthroscopic rotator cuff repair. An institutional shoulder surgery registry query identified 627 patients who underwent arthroscopic rotator cuff repair between 2006 and 2015. Measured range of motion, patient satisfaction, and patient-reported outcome measures were analyzed for preoperative, 3-month, 6-month, 1-year, and 2-year intervals. Subgroup analysis was performed on the basis of tear size by retraction grade and number of anchors used. As an entire group, the plateau of maximum recovery for pain, function, and motion occurred at 1 year. Satisfaction with surgery was >96% at all time points. At 3 months, 74% of improvement in pain and 45% to 58% of functional improvement were realized. However, only 22% of elevation improvement was achieved (P < .001). At 6 months, 89% of improvement in pain, 81% to 88% of functional improvement, and 78% of elevation improvement were achieved (P < .001). Larger tears had a slower speed of recovery for Single Assessment Numeric Evaluation scores, forward elevation, and external rotation. Smaller tears had higher motion and functional scores across all time points. Tear size did not influence pain levels. The plateau of maximum recovery after rotator cuff repair occurred at 1 year with high satisfaction rates at all time points. At 3 months, approximately 75% of pain relief and 50% of functional recovery can be expected. Larger tears have a slower speed of recovery. Copyright © 2016 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

  10. Percutaneous vertebroplasty with the rotational fluoroscopy imaging technique.

    Science.gov (United States)

    Cannavale, Alessandro; Salvatori, Filippo Maria; Wlderk, Andrea; Cirelli, Carlo; d'Adamo, Alessandro; Fanelli, Fabrizio

    2014-11-01

    To evaluate the feasibility of the rotational angiography unit (RAU) as a single technique to guide percutaneous vertebroplasty (PVP). Twenty-five consecutive patients (35 vertebral bodies, 20 lumbar and 15 thoracic) were treated using RA fluoroscopy. Using a state-of-the-art flat-panel angiographer (Artis zee, Siemens, Erlangen, Germany), rotational acquisitions were obtained in all patients for immediate post-procedure 2D/3D reconstructions. Pre- and postoperative back pain was assessed with the visual analog scale (VAS). Fluoroscopy time, patient radiation dose exposure, technical success, mean procedure time, mean number of rotational acquisitions and procedural complications were recorded. All features were compared with a historical cohort of patients (N = 25) who underwent PVP under CT and mobile C-arm fluoroscopy guidance. In all cases, safe and accurate control of the needle insertion and bone-cement injection was successfully obtained with high-quality fluoroscopy images. One cement leakage was detected in the RAU group, and two leakages were detected in the CT and C-arm fluoroscopy group. Technical features were significantly different between the two groups (RAU vs. CT): mean procedure time: 38.2 min vs. 60.2 min (p = 0.02); median fluoroscopy time: 14.58 and 4.58 min (p = 0.02); median number of rotational acquisitions: 5 vs. 10 (p = 0.02); mean patient dose: 6 ± 1.3 mSv vs. 23 ± 1.3 mSv (p = 0.02). There were minor complications (pain, small hematoma) in two patients (8%) in the study group and three cases (12%) in the control group. RAU guidance is an effective and safe technique for performing PVP because it reduces the procedural time and radiation exposure.

  11. Short Rotation Coppice in Austria - Management and Producticivity

    Science.gov (United States)

    Hochbichler, E.; Hofmann, H.; Bellos, N.; Zeitlinger, C.; Liebhard, P.

    2012-04-01

    In Austria energy wood production in short rotation coppice systems (SRC) becomes increasingly important to meet the demands of the growing bio-energy sector. In order to successfully develop the SRC market, the achievement of high and constant yields in SRC management is just as important as a reliable harvesting technology, which facilitates the production of high quality wood chips. Yield models and site-specific knowledge about productivity are needed with respect to clones, site factors and management alternatives. Therefore in the years 2007 and 2008 experimental plots (Marchfeld; 16 poplar clones and 19 willow clones) and a network of demonstration plots (different regions in Lower Austria; 7 poplar clones, 4 willow clones) were established. Single shoot surveys and biomass functions in combination with stand inventories form the general basis for estimating yield and productivity. They also help to optimize yield and rotation length by taking the maximum harvestable tree diameter into account, which is determined by harvesting techniques. For optimizing the yield estimation of SRC stands, preliminary clone specific yield functions for poplar and willow clones were developed. These specific yield functions were based on common yield estimation functions with respect to the newly used clones (e.g. faster growth, lower wood density), using a regression analytical approach. Standard stand surveys were carried out in autumn 2007, 2008, 2009 and 2010. We were able to show a high variety in biomass production of poplar and willow clones on the specific site. For the first and second rotation cycle the mean productivity of poplar clones was within a range of 4 - 12 t/y/ha and for willow clones within a range of 3 - 17 t/y/ha. These results were compared with the productivity of older experimental plots in Austria. Based on the preliminary results of productivity of poplar and willow clones for various site factors and management alternatives (planting design

  12. Percutaneous vertebroplasty with the rotational fluoroscopy imaging technique

    Energy Technology Data Exchange (ETDEWEB)

    Cannavale, Alessandro; Salvatori, Filippo Maria; Wlderk, Andrea; Cirelli, Carlo; D' Adamo, Alessandro; Fanelli, Fabrizio [University of Rome, Vascular and Interventional Unit, Department of Radiological Sciences, Rome (Italy)

    2014-11-15

    To evaluate the feasibility of the rotational angiography unit (RAU) as a single technique to guide percutaneous vertebroplasty (PVP). Twenty-five consecutive patients (35 vertebral bodies, 20 lumbar and 15 thoracic) were treated using RA fluoroscopy. Using a state-of-the-art flat-panel angiographer (Artis zee, Siemens, Erlangen, Germany), rotational acquisitions were obtained in all patients for immediate post-procedure 2D/3D reconstructions. Pre- and postoperative back pain was assessed with the visual analog scale (VAS). Fluoroscopy time, patient radiation dose exposure, technical success, mean procedure time, mean number of rotational acquisitions and procedural complications were recorded. All features were compared with a historical cohort of patients (N = 25) who underwent PVP under CT and mobile C-arm fluoroscopy guidance. In all cases, safe and accurate control of the needle insertion and bone-cement injection was successfully obtained with high-quality fluoroscopy images. One cement leakage was detected in the RAU group, and two leakages were detected in the CT and C-arm fluoroscopy group. Technical features were significantly different between the two groups (RAU vs. CT): mean procedure time: 38.2 min vs. 60.2 min (p = 0.02); median fluoroscopy time: 14.58 and 4.58 min (p = 0.02); median number of rotational acquisitions: 5 vs. 10 (p = 0.02); mean patient dose: 6 ± 1.3 mSv vs. 23 ± 1.3 mSv (p = 0.02). There were minor complications (pain, small hematoma) in two patients (8%) in the study group and three cases (12%) in the control group. RAU guidance is an effective and safe technique for performing PVP because it reduces the procedural time and radiation exposure. (orig.)

  13. Rotating Reverse-Osmosis for Water Purification

    Science.gov (United States)

    Lueptow, RIchard M.

    2004-01-01

    A new design for a water-filtering device combines rotating filtration with reverse osmosis to create a rotating reverse- osmosis system. Rotating filtration has been used for separating plasma from whole blood, while reverse osmosis has been used in purification of water and in some chemical processes. Reverse- osmosis membranes are vulnerable to concentration polarization a type of fouling in which the chemicals meant not to pass through the reverse-osmosis membranes accumulate very near the surfaces of the membranes. The combination of rotating filtration and reverse osmosis is intended to prevent concentration polarization and thereby increase the desired flux of filtered water while decreasing the likelihood of passage of undesired chemical species through the filter. Devices based on this concept could be useful in a variety of commercial applications, including purification and desalination of drinking water, purification of pharmaceutical process water, treatment of household and industrial wastewater, and treatment of industrial process water. A rotating filter consists of a cylindrical porous microfilter rotating within a stationary concentric cylindrical outer shell (see figure). The aqueous suspension enters one end of the annulus between the inner and outer cylinders. Filtrate passes through the rotating cylindrical microfilter and is removed via a hollow shaft. The concentrated suspension is removed at the end of the annulus opposite the end where the suspension entered.

  14. Rotational excitation of molecules by electron collisions

    International Nuclear Information System (INIS)

    Itikawa, Yukikazu; Mason, Nigel

    2005-01-01

    The anisotropic charge distribution of a molecule can easily induce a rotational transition in the molecule during an electron collision. Further, since the level spacing of the rotational states is very small, the transition can take place over a wide range of electron energies. The rotational excitation is the dominant energy-loss process for an electron in a molecular gas, when the electron energy lies below the vibrational threshold of the molecule. In the case of polar molecules, the rotationally excited molecule promptly emits microwave (or far infrared) radiation. In this way, the rotational excitation effectively cools electrons. The present paper reviews theoretical and experimental studies of the electron-impact rotational excitation of molecules. After a general introduction of the relevant theory and experiment, case studies of five different molecular species (H 2 , N 2 , CH 4 , HCl, and H 2 O) are presented to show the characteristics of rotational cross sections. From those studies, common features of the cross sections are discussed

  15. Effect of Laser Injection Seeder on Rotationally Resolved Spectra of Benzonitrile

    Energy Technology Data Exchange (ETDEWEB)

    Hai-Feng, X.; Sears, T.; Philip, M.J.

    2010-08-01

    High resolution lasers are necessary to derive the most information from molecular spectra. However, their use uncovers some photophysical processes that compromise the ability to resolve rotational structure. We study the influence of laser optical mode structure on the high resolution spectra of the S{sub 1} states of benzonitrile in a supersonic molecular beam using an Ar{sup +} pumped cw ring dye laser which is amplified by a pulsed Nd:YAG laser. The latter could be operated either in one optical mode by injecting (seeding) its oscillator with a single mode diode laser, or with many optical modes by not using the seeder. Rotationally resolved lines are obtained when the oscillator of the YAG laser are operated in one single optical mode, but only a continuum is seen when the YAG laser has multiple modes. It is argued that the ac Stark effect is the most probable reason for broadening and blurring the rotational lines.

  16. Multi-model uncertainty analysis in predicting grain N for crop rotations in Europe

    DEFF Research Database (Denmark)

    Yin, Xiaogang; Kersebaum, Kurt C; Kollas, Chris

    2017-01-01

    simulating different treatments (catch crops, CO2 concentrations, irrigation, N application, residues and tillage) in four multi-year rotation experiments in Europe to assess modelling accuracy. Seven grain and seed crops in four rotation systems in Europe were included in the study, namely winter wheat...... than a random single model. Models correctly simulated the effects of enhanced N input on grain N of winter wheat and winter barley, whereas effects of tillage and irrigation were less well estimated. However, the use of continuous simulation did not improve the simulations as compared to single year......Realistic estimation of grain nitrogen (N; N in grain yield) is crucial for assessing N management in crop rotations, but there is little information on the performance of commonly used crop models for simulating grain N. Therefore, the objectives of the study were to (1) test if continuous...

  17. Pulley lesions in rotator cuff tears: prevalence, etiology, and concomitant pathologies.

    Science.gov (United States)

    Hawi, Nael; Liodakis, Emmanouil; Garving, Christina; Habermeyer, Peter; Tauber, Mark

    2017-08-01

    This study aimed to demonstrate the prevalence of lesions in the biceps pulley complex in a representative, consecutive series of rotator cuff tears and rotator cuff interval treatments. We also analyzed associated tear pattern of rotator cuff injuries and superior labrum anterior-posterior (SLAP) lesions. We evaluated the relationships of these lesions to traumatic genesis and the prevalence of pulley lesions in revision cases. This retrospective study analyzed all pre- and intra-operative documentation on arthroscopic rotator cuff reconstructions and isolated pulley lesion treatments performed by a single surgeon over 2 consecutive years. According to Habermeyer et al., we classified cases into four groups, based on the presence of additional or related complete or partial rotator cuff tears, SLAP lesions, trauma, and primary or revision surgery. Among 382 patients with rotator cuff tears, 345 (90.3%) had an injured pulley system; 151 (43.8%) had partial tears of the rotator cuff; out of these, 106 (30.6%) were articular-sided. All of these articular-sided partial tears showed extension into the pulley complex. In 154 cases (44.6%), history of shoulder trauma was associated with the beginning of symptoms. In addition, concomitant SLAP lesions occurred in 25-62% of pulley lesions, correlating with the severity of pulley lesions. Among the 345 cases, there have been 32 (9.3%) revision cases where a pulley lesion was intra-operatively identified and addressed. Pulley complex lesions are present in 90.3% of surgically treated rotator cuff lesions, particularly in articular-sided injuries. In addition, we found a significant relationship between the incidence of SLAP lesions and the severity of pulley lesions. It seems reasonable to assume an important role of pulley system injuries in the pathogenesis of rotator cuff lesions.

  18. Rotating saddle trap as Foucault's pendulum

    Science.gov (United States)

    Kirillov, Oleg N.; Levi, Mark

    2016-01-01

    One of the many surprising results found in the mechanics of rotating systems is the stabilization of a particle in a rapidly rotating planar saddle potential. Besides the counterintuitive stabilization, an unexpected precessional motion is observed. In this note, we show that this precession is due to a Coriolis-like force caused by the rotation of the potential. To our knowledge, this is the first example where such a force arises in an inertial reference frame. We also propose a simple mechanical demonstration of this effect.

  19. Rotating transformers in wind turbine applications

    Energy Technology Data Exchange (ETDEWEB)

    Hylander, J. [Chalmers Univ. of Technology, Goeteborg (Sweden); Engstroem, S. [Aegir konsult AB, Lidingoe (Sweden)

    1996-12-01

    The power consumption of rotating electrical components is often supplied via slip-rings in wind turbines. Slip-ring equipment is expensive and need maintenance and are prone to malfunction. If the slip-rings could be replaced with contact-less equipment better turbines could be designed. This paper presents the design, some FE calculations and some measurements on a prototype rotating transformer. The proposed transformer consists of a secondary rotating winding and a stationary exciting primary winding. The results indicate that this transformer could be used to replace slip-rings in wind turbines. 4 refs, 3 figs

  20. Collapse and equilibrium of rotating, adiabatic clouds

    International Nuclear Information System (INIS)

    Boss, A.P.

    1980-01-01

    A numerical hydrodynamics computer code has been used to follow the collapse and establishment of equilibrium of adiabatic gas clouds restricted to axial symmetry. The clouds are initially uniform in density and rotation, with adiabatic exponents γ=5/3 and 7/5. The numerical technique allows, for the first time, a direct comparison to be made between the dynamic collapse and approach to equilibrium of unconstrained clouds on the one hand, and the results for incompressible, uniformly rotating equilibrium clouds, and the equilibrium structures of differentially rotating polytropes, on the other hand