WorldWideScience

Sample records for hybrid ray mode

  1. In-Situ Fault Detection by the Hybrid Ray-Mode Method

    Science.gov (United States)

    1992-04-20

    this quantity rela- DisEL , + y,L5, (31) tive to the magnitude of the direct P complex ray, given by with (28), evaluated at the lower boundary (i.e...indeed be modeled gated to the lower surface and then to the P-source beam effectively by simple beam tracking that is intimately tied to location

  2. Characterization of continuous and pulsed emission modes of a hybrid micro focus x-ray source for medical imaging applications

    Science.gov (United States)

    Ghani, Muhammad U.; Wong, Molly D.; Ren, Liqiang; Wu, Di; Zheng, Bin; Rong, John. X.; Wu, Xizeng; Liu, Hong

    2017-05-01

    The aim of this study was to quantitatively characterize a micro focus x-ray tube that can operate in both continuous and pulsed emission modes. The micro focus x-ray source (Model L9181-06, Hamamatsu Photonics, Japan) has a varying focal spot size ranging from 16 μm to 50 μm as the source output power changes from 10 to 39 W. We measured the source output, beam quality, focal spot sizes, kV accuracy, spectra shapes and spatial resolution. Source output was measured using an ionization chamber for various tube voltages (kVs) with varying current (μA) and distances. The beam quality was measured in terms of half value layer (HVL), kV accuracy was measured with a non-invasive kV meter, and the spectra was measured using a compact integrated spectrometer system. The focal spot sizes were measured using a slit method with a CCD detector with a pixel pitch of 22 μm. The spatial resolution was quantitatively measured using the slit method with a CMOS flat panel detector with a 50 μm pixel pitch, and compared to the qualitative results obtained by imaging a contrast bar pattern. The focal spot sizes in the vertical direction were smaller than that of the horizontal direction, the impact of which was visible when comparing the spatial resolution values. Our analyses revealed that both emission modes yield comparable imaging performances in terms of beam quality, spectra shape and spatial resolution effects. There were no significantly large differences, thus providing the motivation for future studies to design and develop stable and robust cone beam imaging systems for various diagnostic applications.

  3. Turbo Codes with Hybrid Interleaving Mode

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    In the investigation of turbo codes, either random interleavers or structured interleavers are used. Combined two kinds of interleavers in one turbo encoder, a hybrid interleaving mode is proposed in this paper. Computer simulations show that the performance of turbo codes with the hybrid interleaving mode is better than that with the typical interleaving mode.

  4. Study of Ultra-High Energy Cosmic Ray Composition Using Telescope Array's Middle Drum Detector and Surface Array in Hybrid Mode

    CERN Document Server

    Abbasi, R U; Abu-Zayyad, T; Allen, M; Anderson, R; Azuma, R; Barcikowski, E; Belz, J W; Bergman, D R; Blake, S A; Cady, R; Chae, M J; Cheon, B G; Chiba, J; Chikawa, M; Cho, W R; Fujii, T; Fukushima, M; Goto, T; Hanlon, W; Hayashi, Y; Hayashida, N; Hibino, K; Honda, K; Ikeda, D; Inoue, N; Ishii, T; Ishimori, R; Ito, H; Ivanov, D; Jui, C C H; Kadota, K; Kakimoto, F; Kalashev, O; Kasahara, K; Kawai, H; Kawakami, S; Kawana, S; Kawata, K; Kido, E; Kim, H B; Kim, J H; Kitamura, S; Kitamura, Y; Kuzmin, V; Kwon, Y J; Lan, J; Lim, S I; Lundquist, J P; Machida, K; Martens, K; Matsuda, T; Matsuyama, T; Matthews, J N; Minamino, M; Mukai, Y; Myers, I; Nagasawa, K; Nagataki, S; Nakamura, T; Nonaka, T; Nozato, A; Ogio, S; Ogura, J; Ohnishi, M; Ohoka, H; Oki, K; Okuda, T; Ono, M; Oshima, A; Ozawa, S; Park, I H; Pshirkov, M S; Rodriguez, D C; Rubtsov, G; Ryu, D; Sagawa, H; Sakurai, N; Sampson, A L; Scott, L M; Shah, P D; Shibata, F; Shibata, T; Shimodaira, H; Shin, B K; Shin, H S; Smith, J D; Sokolsky, P; Springer, R W; Stokes, B T; Stratton, S R; Stroman, T; Suzawa, T; Takamura, M; Takeda, M; Takeishi, R; Taketa, A; Takita, M; Tameda, Y; Tanaka, H; Tanaka, K; Tanaka, M; Thomas, S B; Thomson, G B; Tinyakov, P; Tkachev, I; Tokuno, H; Tomida, T; Troitsky, S; Tsunesada, Y; Tsutsumi, K; Uchihori, Y; Udo, S; Urban, F; Vasiloff, G; Wong, T; Yamane, R; Yamaoka, H; Yamazaki, K; Yang, J; Yashiro, K; Yoneda, Y; Yoshida, S; Yoshiia, H; Zollinger, R; Zundel, Z

    2014-01-01

    Previous measurements of the composition of Ultra-High energy Cosmic Rays (UHECRs) made by the High Resolution Fly's Eye (HiRes) and Pierre Auger Observatory (PAO) are seemingly contradictory but utilize different detection methods, as HiRes was a stereo detector and PAO is a hybrid detector. The five year Telescope Array (TA) Middle Drum hybrid composition measurement is similar in methodology to PAO, and good agreement is evident between data and a light, largely protonic composition using simulations from a variety of hadronic models for the comparison of both elongation rate and shower fluctuations. This is in good agreement with the HiRes results. This analysis is presented using two methods: data cuts using simple geometrical variables and a new pattern recognition technique.

  5. Low arc drop hybrid mode thermionic converter

    Science.gov (United States)

    Shimada, K.

    1977-01-01

    The hybrid mode operation for the reduction of plasma drops is being investigated. This report discusses the results obtained from two molybdenum emitter converters. One converter had a molybdenum collector and the other a nickel collector. The molybdenum collector converter was operated in a hybrid mode (at an interelectrode distance of 1.7 mm) and produced a minimum barrier index of 1.96 eV at an emitter temperature of 1500 K. The arc drop was calculated to be 0.14 eV, using the published results for a molybdenum collector. On the other hand, the nickel collector converter was operated in a conventional ignited mode (at an interelectrode distance of 0.5 mm) and produced a minimum barrier index of 2.1 eV at an emitter temperature of 1700 K. It is tentatively concluded that a large-gap operation of the hybrid mode converter permits the diffusion of cesium ions to a distance in the order of one millimeter for an effective neutralization of electron space charge. By employing a low work function collector (1.55 eV) in a hybrid mode converter with an arc drop of 0.14 eV, it appears that a barrier index as low as 1.69 eV could be achieved.

  6. Hybrid modes in a square corrugated waveguide

    Energy Technology Data Exchange (ETDEWEB)

    Ohkubo, K.

    2001-06-01

    By using two scalar eigenfunctions, electric and magnetic fields in the rectangular (or square) corrugated waveguide are analyzed. In a rectangular corrugated waveguide, the boundary conditions on two corrugated and two smooth walls can be satisfied to excite the hybrid mode. In a highly oversized waveguide where the wavelength of dominant mode is close to that in vacuum, two smooth walls can be exchanged with the corrugated walls because the boundary condition at this walls is satisfied approximately. The replacement is possible due to almost no penetration of the electromagnetic fields into the gap of the replaced walls when the direction of main electric field is parallel to the gap of replaced walls. This characteristic enables us to rotate the polarization of the hybrid mode in the oversized square waveguide with all four corrugated walls and is applicable to the remote steering antenna for electron cyclotron heating in the ITER. For a beam injection larger than the critical angle in this antenna, excited higher modes are at a considerably different wavelength from that in vacuum and result in the dissatisfaction of boundary conditions due to millimeter-wave penetration into corrugation gaps in replaced walls. (author)

  7. Characterization of Hybrid Modes in Metamaterial Waveguides

    CERN Document Server

    Beig-Mohammadi, M; Sanders, Barry C; Lavoie, Benjamin R; Kheradmand, R

    2016-01-01

    In this paper, we employ the properties of metamaterials to tailor the modes of metamaterial-dielectric waveguides operating at optical frequencies. We survey the effect of fishnet metamaterial structural parameters such as the magnetic oscillation strength, magnetic resonance frequency and magnetic damping on the double-negative refractive index frequency region in metamaterials and on the hybrid-modes in slab metamaterial-dielectric waveguides. To identify the robustness of the metamaterials to fluctuations in the metamaterial structural parameters, we investigate the behavior of metamaterials under Gaussian errors on their structural parameters. Our survey enables the identification of appropriate metamaterial unit-cell structure and the permissive fluctuations on the structural parameters for further applications of metamaterials in waveguide technologies.

  8. Investigation of lower hybrid current drive during H-mode in EAST tokamak

    Institute of Scientific and Technical Information of China (English)

    Li Miao-Hui; Liu Fu-Kun; Wang Mao; Xu Han-Dong; Wan Bao-Nian; Ding Bo-Jiang; Kong Er-Hua; Zhang Lei; Zhang Xin-Jun; Qian Jin-Ping; Yan Ning; Han Xiao-Feng; Shan Jia-Fang

    2011-01-01

    H-mode discharges with lower hybrid current drive (LHCD) alone are achieved in EAST divertor plasma over a wide parameter range.These H-mode discharges are characterized by a sudden drop in Dα emission and a spontaneous rise in main plasma density.Good lower hybrid (LH) coupling during H-mode is obtained by putting the plasma close to the antenna and by injecting D2 gas from a pipe near the grill mouse.The analysis of lower hybrid current drive properties shows that the LH deposition profile shifts off axis during H-mode,and current drive (CD) efficiency decreases due to the increase in density.Modeling results of H-mode discharges with a general ray tracing code GENRAY are reported.

  9. Lower hybrid to whistler mode conversion on a density striation

    CERN Document Server

    Camporeale, Enrico; Colestock, Patrick

    2013-01-01

    When a wave packet composed of short wavelength lower hybrid modes traveling in an homogeneous plasma region encounters an inhomogeneity, it can resonantly excite long wavelength whistler waves via a linear mechanism known as mode conversion. An enhancement of lower hybrid/whistler activity has been often observed by sounding rockets and satellites in the presence of density depletions (striations) in the upper ionosphere. We address here the process of linear mode conversion of lower hybrid to whistler waves, mediated by a density striation, using a scalar-field formalism (in the limit of cold plasma linear theory) which we solve numerically. We show that the mode conversion can effectively transfer a large amount of energy from the short to the long wavelength modes. We also study how the efficiency scales by changing the properties (width and amplitude) of the density striation. We present a general criterion for the width of the striation that, if fulfilled, maximizes the conversion efficiency. Such a cri...

  10. A Hybrid Mode and a Classification of Beam Plasma Instabilities

    Science.gov (United States)

    2014-09-26

    classification scheme, based on the beam energy and beam density. This classification identifies the domains for the hybrid mode, the Weibel mode,13 and...the classical two stream instabilities. In that section, we also furnish a simple derivation of the Weibel mode for a relativist..c electron beam...w p which is non-zero. This mode has been called a Weibel mode,1 3𔃻 4 and is predominant in Domain III in the classification shown in Fig. 4. (B2

  11. Mode coupling in hybrid square-rectangular lasers for single mode operation

    Science.gov (United States)

    Ma, Xiu-Wen; Huang, Yong-Zhen; Yang, Yue-De; Xiao, Jin-Long; Weng, Hai-Zhong; Xiao, Zhi-Xiong

    2016-08-01

    Mode coupling between a square microcavity and a Fabry-Pérot (FP) cavity is proposed and demonstrated for realizing single mode lasers. The modulations of the mode Q factor as simulation results are observed and single mode operation is obtained with a side mode suppression ratio of 46 dB and a single mode fiber coupling loss of 3.2 dB for an AlGaInAs/InP hybrid laser as a 300-μm-length and 1.5-μm-wide FP cavity connected to a vertex of a 10-μm-side square microcavity. Furthermore, tunable single mode operation is demonstrated with a continuous wavelength tuning range over 10 nm. The simple hybrid structure may shed light on practical applications of whispering-gallery mode microcavities in large-scale photonic integrated circuits and optical communication and interconnection.

  12. General motors front wheel drive 2-mode hybrid transmission

    Energy Technology Data Exchange (ETDEWEB)

    Hendrickson, James [General Motors Corp., Pontiac, MI (United States). New Transmission Products Group.; Holmes, Alan G. [General Motors Corp., Pontiac, MI (United States). Powertrain Hybrid Architecture

    2009-07-01

    General Motors now expands the application of two-mode hybrid technology to front wheel drive vehicles with the development of a hybrid electric transmission packaged into essentially the same space as a conventional automatic transmission for front wheel drive. This was accomplished using a space-efficient arrangement based on two planetary gear sets and electric motor-generators with large internal diameters. A combination of damper and hydraulically-controlled clutch allow comfortable shutdown and restarting of large-displacement engines in front wheel drive vehicles. The hybrid system delivers electric low-speed urban driving, two continuously variable ranges of transmission speed ratios, four fixed transmission speed ratios, electric acceleration boosting, and regenerative braking. In the first vehicle application, the two-mode hybrid helps to reduce vehicle fuel consumption by approximately one-third. (orig.)

  13. A hybrid formulation of a component mode synthesis method

    Science.gov (United States)

    Farhat, Charbel; Geradin, Michel

    1992-01-01

    Component mode synthesis is a substructuring technique frequently employed in structural dynamics. In this method, a given structure is subdivided into components or substructures, each of which is analyzed independently for natural frequencies and for mode shapes. The substructure mode shapes are then assembled to give displacement shapes or load patterns of the original structure. An analytical justification of the basic concept is presented using spectral decompositions, and a variant substructuring approach where intersubstructure continuity is enforced in a weak form is derived. This leads to a hybrid formulation of the basic method which is particularly suitable for assembling heterogeneous substructures and analyzing nonconforming and incompatible finite element substructure models. For problems where both the basic and hybrid methods are applicable, the hybrid variant can be computationally more advantageous.

  14. Multiview coding mode decision with hybrid optimal stopping model.

    Science.gov (United States)

    Zhao, Tiesong; Kwong, Sam; Wang, Hanli; Wang, Zhou; Pan, Zhaoqing; Kuo, C-C Jay

    2013-04-01

    In a generic decision process, optimal stopping theory aims to achieve a good tradeoff between decision performance and time consumed, with the advantages of theoretical decision-making and predictable decision performance. In this paper, optimal stopping theory is employed to develop an effective hybrid model for the mode decision problem, which aims to theoretically achieve a good tradeoff between the two interrelated measurements in mode decision, as computational complexity reduction and rate-distortion degradation. The proposed hybrid model is implemented and examined with a multiview encoder. To support the model and further promote coding performance, the multiview coding mode characteristics, including predicted mode probability and estimated coding time, are jointly investigated with inter-view correlations. Exhaustive experimental results with a wide range of video resolutions reveal the efficiency and robustness of our method, with high decision accuracy, negligible computational overhead, and almost intact rate-distortion performance compared to the original encoder.

  15. DEFORMATION RIGIDITY OF ASSUMED STRESS MODES IN HYBRID ELEMENTS

    Institute of Scientific and Technical Information of China (English)

    ZHANG Can-hui; HUANG Qian; FENG Wei

    2006-01-01

    The new methods to determine the zero-energy deformation modes in the hybrid elements and the zero-energy stress modes in their assumed stress fields are presented by the natural deformation modes of the elements. And the formula of the additional element deformation rigidity due to additional mode into the assumed stress field is derived.Based on, it is concluded in theory that the zero-energy stress mode cannot suppress the zero-energy deformation modes but increase the extra rigidity to the nonzero-energy deformation modes of the element instead. So they should not be employed to assume the stress field. In addition, the parasitic stress modes will produce the spurious parasitic energy and result the element behaving over rigidity. Thus, they should not be used into the assumed stress field even though they can suppress the zero-energy deformation modes of the element. The numerical examples show the performance of the elements including the zero-energy stress modes or the parasitic stress modes.

  16. Nonlinear spatial mode imaging of hybrid photonic crystal fibers

    DEFF Research Database (Denmark)

    Petersen, Sidsel Rübner; Alkeskjold, Thomas Tanggaard; Laurila, Marko;

    2013-01-01

    Degenerate spontaneous four wave mixing is studied for the rst time in a large mode area hybrid photonic crystal ber, where light con nement is achieved by combined index- and bandgap guiding. Four wave mixing products are generated on the edges of the bandgaps, which is veri ed by numerical...

  17. Monolithic Hybrid and Passive Mode-Locked 40GHz Quantum Dot Laser Diodes

    DEFF Research Database (Denmark)

    Thompson, M. G.; Larsson, David; Rae, A. R.

    2006-01-01

    For the first time hybrid and passive mode-locking jitter performance is investigated in 40GHz quantum-dot mode-locked lasers. Record low passive mode-locking jitter of 219fs is presented, along with promising hybrid mode-locking results of 124fs.......For the first time hybrid and passive mode-locking jitter performance is investigated in 40GHz quantum-dot mode-locked lasers. Record low passive mode-locking jitter of 219fs is presented, along with promising hybrid mode-locking results of 124fs....

  18. Monolithic Hybrid and Passive Mode-Locked 40GHz Quantum Dot Laser Diodes

    DEFF Research Database (Denmark)

    Thompson, M. G.; Larsson, David; Rae, A. R.;

    2006-01-01

    For the first time hybrid and passive mode-locking jitter performance is investigated in 40GHz quantum-dot mode-locked lasers. Record low passive mode-locking jitter of 219fs is presented, along with promising hybrid mode-locking results of 124fs.......For the first time hybrid and passive mode-locking jitter performance is investigated in 40GHz quantum-dot mode-locked lasers. Record low passive mode-locking jitter of 219fs is presented, along with promising hybrid mode-locking results of 124fs....

  19. Recent progress in hybrid mode thermionic converter development

    Science.gov (United States)

    Shimada, K.

    1979-01-01

    Thermionic research has been conducted to investigate a hybrid-mode thermionic converter as a candidate for reducing the barrier index. The hybrid-mode thermionic converter is designed to operate in a combination ignited mode and unignited mode by using a series of parallel grooves in the emitter. The emitter material is molybdenum and the non-grooved land area is thinly coated with rhenium metal. When the emitter is exposed to cesium vapor, as it is during the converter operation, the rhenium-coated land area achieves a lower work function than the grooved molybdenum surface by as much as 0.5 eV. The low work function land area provides a major portion of electron emission, and the high work function grooved area provides cesium ions required for efficient transport of electrons generated in adjacent land areas to the collector. Experimental results obtained from two different converters and a numerical analysis of converter characteristics are presented in this paper.

  20. Hybrid sliding mode control of semi-active suspension systems

    Science.gov (United States)

    Assadsangabi, Babak; Eghtesad, Mohammad; Daneshmand, Farhang; Vahdati, Nader

    2009-12-01

    In order to design a controller which can take both ride comfort and road holding into consideration, a hybrid model reference sliding mode controller (HMRSMC) is proposed. The controller includes two separate model reference sliding mode controllers (MRSMC). One of the controllers is designed so as to force the plant to follow the ideal Sky-hook model and the other is to force the plant to follow the ideal Ground-hook model; then the outputs of these two controllers are linearly combined and applied to the plant as the input. Also, since the designed controller requires a knowledge of the terrain input, this input is approximated by the unsprung mass displacement. Finally, in the simulation section of this study, the effect of the relative ratio between the two MRSMCs and the knowledge of the terrain on the performance of the controller is numerically investigated for both steady-state and transient cases.

  1. Backstepping and sliding mode control hybridized for a prosthetic hand.

    Science.gov (United States)

    Engeberg, Erik D; Meek, Sanford G

    2009-02-01

    Open loop and force controllers are compared experimentally with three robust parallel force-velocity controllers that are developed for a prosthetic hand. Robust sliding mode, backstepping, and hybrid sliding mode-backstepping (HSMBS) parallel force-velocity controllers are tested by ten able-bodied subjects. Results obtained with a myoelectrically controlled prosthesis indicate that all three robust controllers offer a statistically significant improvement over linear hand prosthesis control schemes. The robust controllers enable the human operators to more easily manipulate a delicate object. Bench top experiments combined with quantitative and qualitative evaluations from ten test subjects reveal the HSMBS controller to be the best choice to improve control of powered prosthetic hands.

  2. Magnetospheric Whistler Mode Ray Tracing with the Inclusion of Finite Electron and Ion Temperature

    Science.gov (United States)

    Maxworth, A. S.; Golkowski, M.

    2015-12-01

    Ray tracing is an important technique for the study of whistler mode wave propagation in the Earth's magnetosphere. In numerical ray tracing the trajectory of a wave packet is calculated at each point in space by solving the Haselgrove equations, assuming a smooth, loss-less medium with no mode coupling. Previous work on ray tracing has assumed a cold plasma environment with negligible electron and ion temperatures. In this work we present magnetospheric whistler mode wave ray tracing results with the inclusion of finite ion and electron temperature. The inclusion of finite temperature effects makes the fourth order dispersion relation become sixth order. We compare our results with the work done by previous researchers for cold plasma environments, using two near earth space models (NGO and GCPM). Inclusion of finite temperature closes the otherwise open refractive index surface near the lower hybrid resonance frequency and affects the magnetospheric reflection of whistler waves. We also asses the main changes in the ray trajectory and implications for cyclotron resonance wave particle interactions including energetic particle precipitation.

  3. Ray analysis of a class of hybrid cylindrical aircraft wings

    OpenAIRE

    Jha, RM; Bokhari, SA; Sudhakan, V; Mahapatra, PR

    1988-01-01

    A new approach to the modelling of aircraft wings, based on the combination of hybrid quadric (parabolic and circular) cylinders, has been presented for electromagnetic applications. Closed-form expressions have been obtained for ray parameters required in the high-frequency mutual coupling computation of antenna pairs located arbitrarily on an aircraft wing.

  4. Frequency conversion through spontaneous degenerate four wave mixing in large mode area hybrid photonic crystal fibers

    DEFF Research Database (Denmark)

    Petersen, Sidsel Rübner; Alkeskjold, Thomas Tanggaard; Olausson, Christina Bjarnal Thulin;

    2014-01-01

    Frequency conversion through spontaneous degenerate four wave mixing (FWM) is investigated in large mode area hybrid photonic crystal fibers. Different FWM processes are observed, phasematching between fiber modes of orthogonal polarization, intermodal phasematching across bandgaps, and intramodal...

  5. Hybridization of photon-plasmon modes in metal-coated microtubular cavities

    CERN Document Server

    Yin, Yin; Engemaier, Vivienne; Giudicatti, Silvia; Naz, Ehsan Saei Ghareh; Ma, Libo; Schmidt, Oliver G

    2016-01-01

    The coupling of resonant light and surface plasmons in metal layer coated optical microcavities results in the formation of hybrid photon-plasmon modes. Here, we comprehensively investigate the hybridization mechanism of photon-plasmon modes based on opto-plasmonic microtubular cavities. By changing the cavity structure and the metal layer thickness, weakly, moderately and strongly hybridized resonant modes are demonstrated depending on the photon-plasmon coupling strength. An effective potential approach is applied to illustrate the hybridization of photon-plasmon modes relying on the competition between light confinement by the cavity wall and the potential barrier introduced by the metal layer. Our work reveals the basic physical mechanisms for the generation of hybrid modes in metal-coated whispering-gallery-mode microcavities, and is of importance for the study of enhanced light-matter interactions and potential sensing applications.

  6. Hybrid Pixel Detectors for gamma/X-ray imaging

    Science.gov (United States)

    Hatzistratis, D.; Theodoratos, G.; Zografos, V.; Kazas, I.; Loukas, D.; Lambropoulos, C. P.

    2015-09-01

    Hybrid pixel detectors are made by direct converting high-Z semi-insulating single crystalline material coupled to complementary-metal-oxide semiconductor (CMOS) readout electronics. They are attractive because direct conversion exterminates all the problems of spatial localization related to light diffusion, energy resolution, is far superior from the combination of scintillation crystals and photomultipliers and lithography can be used to pattern electrodes with very fine pitch. We are developing 2-D pixel CMOS ASICs, connect them to pixilated CdTe crystals with the flip chip and bump bonding method and characterize the hybrids. We have designed a series of circuits, whose latest member consists of a 50×25 pixel array with 400um pitch and an embedded controller. In every pixel a full spectroscopic channel with time tagging information has been implemented. The detectors are targeting Compton scatter imaging and they can be used for coded aperture imaging too. Hybridization using CMOS can overcome the limit put on pixel circuit complexity by the use of thin film transistors (TFT) in large flat panels. Hybrid active pixel sensors are used in dental imaging and other applications (e.g. industrial CT etc.). Thus X-ray imaging can benefit from the work done on dynamic range enhancement methods developed initially for visible and infrared CMOS pixel sensors. A 2-D CMOS ASIC with 100um pixel pitch to demonstrate the feasibility of such methods in the context of X-ray imaging has been designed.

  7. An X-ray scanner prototype based on a novel hybrid gaseous detector

    CERN Document Server

    Iacobaeus, C; Lund-Jensen, B; Peskov, Vladimir

    2007-01-01

    We have developed a prototype of a new type of hybrid X-ray detector. It contains a thin wall (few μm) edge- illuminated lead glass capillary plate (acting as a converter of X-rays photons to primary electrons) combined with a microgap parallel-plate avalanche chamber operating in various gas mixtures at 1 atm. The operation of these converters was studied in a wide range of X-ray energies (from 6 to 60 keV) at incident angles varying from 0° to 90°. The detection efficiency, depending on the geometry, photon's energy, incident angle and the mode of operation, was between a few and 40%. The position resolution achieved was 50 μm in digital form and was practically independent of the photon's energy or gas mixture. The developed detector may open new possibilities for medical imaging, for example in mammography, portal imaging, radiography (including security devices), crystallography and many other applications.

  8. Unified Scattering Parameters formalism in terms of Coupled-Mode Theory for investigating hybrid single-mode/two-mode photonic interconnects

    Directory of Open Access Journals (Sweden)

    Boucher Yann G.

    2017-01-01

    Full Text Available In terms of Linear Algebra, a directional coupler between a single-mode waveguide and a two-mode waveguide can be thought of as formally equivalent to a set of three mutually coupled single-mode waveguides. Its responses, easily derived in the frame of ternary Coupled-Mode Theory, are used to establish analytically the scattering parameters of a hybrid ring-based modal multiplexer.

  9. Unified Scattering Parameters formalism in terms of Coupled-Mode Theory for investigating hybrid single-mode/two-mode photonic interconnects

    Science.gov (United States)

    Boucher, Yann G.; Parini, Alberto; Féron, Patrice

    2017-03-01

    In terms of Linear Algebra, a directional coupler between a single-mode waveguide and a two-mode waveguide can be thought of as formally equivalent to a set of three mutually coupled single-mode waveguides. Its responses, easily derived in the frame of ternary Coupled-Mode Theory, are used to establish analytically the scattering parameters of a hybrid ring-based modal multiplexer.

  10. Onset of Bonding Plasmon Hybridization Preceded by Gap Modes in Dielectric Splitting of Metal Disks

    DEFF Research Database (Denmark)

    Frederiksen, Maj; Bochenkov, Vladimir; Ogaki, Ryosuke;

    2013-01-01

    Dielectric splitting of nanoscale disks was studied experimentally and via finite-difference time-domain (FDTD) simulations through systematic introduction of multiple ultrathin dielectric layers. Tunable, hybridized dark bonding modes were seen with first-order gap modes preceding the appearance...... of bonding dipole−dipole disk modes. The observed bright dipolar mode did not show the energy shift expected from plasmon hybridization but activated dark higher order gap modes. Introducing lateral asymmetry was shown to remodel the field distribution resulting in 3D asymmetry that reoriented the dipole...

  11. Measurements of Si Hybrid CMOS X-Ray Detector Characteristics

    CERN Document Server

    Bongiorno, Stephen D; Burrows, David N; Cook, Robert; Bai, Yibin; Farris, Mark

    2009-01-01

    The development of Hybrid CMOS Detectors (HCDs) for X-Ray telescope focal planes will place them in con- tention with CCDs on future satellite missions due to their faster frame rates, flexible readout scenarios, lower power consumption, and inherent radiation hardness. CCDs have been used with great success on the current generation of X-Ray telescopes (e.g. Chandra, XMM, Suzaku, and Swift). However their bucket-brigade read-out architecture, which transfers charge across the chip with discrete component readout electronics, results in clockrate limited readout speeds that cause pileup (saturation) of bright sources and an inherent susceptibility to radiation induced displacement damage that limits mission lifetime. In contrast, HCDs read pixels with low power, on-chip multiplexer electronics in a random access fashion. Faster frame rates achieved with multi-output readout design will allow the next generation's larger effective area telescopes to observe bright sources free of pileup. Radiation damaged latt...

  12. Hard X-rays from hybrid X pinches

    Energy Technology Data Exchange (ETDEWEB)

    Shelkovenko, T. A., E-mail: tc50@cornell.edu; Pikuz, S. A., E-mail: tc50@cornell.edu [Cornell University, Ithaca, New York, 14853, USA and P. N. Lebedev Institute, 53 Leninskii Prospect, Moscow, 119991 (Russian Federation); Hoyt, C. L.; Cahill, A. D.; Hammer, D. A. [Cornell University, Ithaca, New York, 14853 (United States); Tilikin, I. N.; Mingaleev, A. R.; Agafonov, A. V. [P. N. Lebedev Institute, 53 Leninskii Prospect, Moscow, 119991 (Russian Federation)

    2014-12-15

    X pinches are well known to produce very small, dense plasma pinches (“hot spots”) that emit short bursts of 1.5–8 keV radiation. Hard X-ray radiation in the 8–100 keV range is also emitted, only a small portion of which is associated with the X-pinch hot spot. In hybrid X-pinches, the “long” X-ray pulse is terminated by fast closure of the gap between the two conical electrodes by rapidly expanding electrode plasmas. The temporal, spectral, and spatial properties of this higher energy radiation, 10 – 60 keV, have been studied. This radiation was used for point-projection imaging with magnification between 1.5 and 3, and spatial resolution less than100 micrometers was demonstrated.

  13. Surface-plasmon mode hybridization in sub-wavelength microdisk lasers

    CERN Document Server

    Perahia, R; Safavi-Naeini, A; Painter, O

    2009-01-01

    Hybridization of surface-plasmon and dielectric waveguide whispering-gallery modes are demonstrated in a semiconductor microdisk laser cavity of sub-wavelength proportions. A metal layer is deposited on top of the semiconductor microdisk, the radius of which is systematically varied to enable mode hybridization between surface-plasmon and dielectric modes. The anti-crossing behavior of the two cavity mode types is experimentally observed via photoluminescence spectroscopy and optically pumped lasing action at a wavelength of 1.3 micron is achieved at room temperature.

  14. Intermodal parametric gain of degenerate four wave mixing in large mode area hybrid photonic crystal fibers

    OpenAIRE

    Petersen, Sidsel Rübner; Lægsgaard, Jesper; Alkeskjold, Thomas Tanggaard

    2013-01-01

    Intermodal degenerate four wave mixing (FWM) is investigated numerically in large mode area hybrid photonic crystal fibers. The dispersion is controlled independently of core size, and thus allows for power scaling of the FWM process.

  15. Formation of a hybrid plasmonic waveguide mode probed by dispersion measurement

    Energy Technology Data Exchange (ETDEWEB)

    Saito, H. [Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011 (Japan); Quantum Nanoelectronics Research Center, Tokyo Institute of Technology, Oh-Okayama, Meguro-ku, Tokyo 152-8551 (Japan); Kurata, H., E-mail: kurata@eels.kuicr.kyoto-u.ac.jp [Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011 (Japan)

    2015-04-07

    Hybrid waveguides, i.e., dielectric waveguides combined with plasmonic waveguides, have great potential for concomitantly exhibiting subwavelength confinement and long range propagation, enabling a highly integrated photonic circuit. We report the characterization of hybrid waveguide modes excited in Si/SiO{sub 2}/Al films, by dispersion measurement using angle-resolved electron energy-loss spectroscopy. This experiment directly verifies the formation of the hybrid waveguide mode with a strongly localized electromagnetic field in a 6-nm-thick SiO{sub 2} layer. The results clearly describe the characteristic behavior of the hybrid waveguide mode, which depends on the effective index of the constituent dielectric waveguide and the surface plasmon-polariton modes.

  16. Intermodal parametric gain of degenerate four wave mixing in large mode area hybrid photonic crystal fibers

    DEFF Research Database (Denmark)

    Petersen, Sidsel Rübner; Lægsgaard, Jesper; Alkeskjold, Thomas Tanggaard

    2013-01-01

    Intermodal degenerate four wave mixing (FWM) is investigated numerically in large mode area hybrid photonic crystal fibers. The dispersion is controlled independently of core size, and thus allows for power scaling of the FWM process.......Intermodal degenerate four wave mixing (FWM) is investigated numerically in large mode area hybrid photonic crystal fibers. The dispersion is controlled independently of core size, and thus allows for power scaling of the FWM process....

  17. Hybrid Cosmic Ray Detector at Pico de Orizaba

    Science.gov (United States)

    Cotzomi, J.; Martinez, O.; Medina, M.; Moreno, E.; Salazar, H.; Ponce, G.; Pérez, L.; Villaseñor, L.; Khrenov, B.; Garipov, G.

    2003-07-01

    In this work we present the design features and simulation of the hybrid detector under construction at 4300 m.a.s.l. equivalent to 620 g /cm2 .The goal of this observatory is to study the mass composition of the cosmic rays in the energy range of 1015 - 1018 eV. The observation technique include particle counting and fluorescence detection in order to improve the Energy and Xmax determination. This approach allow us to contribute in the knowledge of the knee composition, corresponding to medium to heavy nuclei. Introduction One of the open problems of the high energy cosmic ray is the composition of the primary particles with energies from 1 × 1015 to 1 × 1018 . In order to contribute to solve this issue, we have design and hybrid detector to be located in the Pico de Orizaba and Sierra la Negra Volcano es. One of the advantages of the site is the altitude, 4200 m.a.s.l, which may help us to observe the extended air showers nearby their maximum development, improving the determination of the parameters of the primary particle. The optical properties of the site have been studied by several years, showing stability and darkness to declare it as a good optical astronomical site. So, we thought that the installation of an fluorescence telescope, should complement the ground array and improve the overall performance of this observatory. In the other side, the implementation of the hybrid technique, based in montecarlo simulations, may allow us to separate the light and the heavy primary components. Based in simulations, we expect good quality measurement of the number of secondary particles due to the proximity of the array to the level of maximum development of the EAS Xmax .

  18. Large-mode-area hybrid photonic crystal fiber amplifier at 1178 nm

    DEFF Research Database (Denmark)

    Petersen, Sidsel Rübner; Chen, Mingchen; Shirakawa, Akira

    2015-01-01

    Amplification of 1178 nm light is demonstrated in a large-mode-area single-mode ytterbium-doped hybrid photonic crystal fiber, relying on distributed spectral filtering of spontaneous emission at shorter wavelengths. An output power of 53 W is achieved with 29 dB suppression of parasitic lasing...

  19. Design of Engine-Generator Work Mode for Hybrid Electric Vehicle

    Institute of Scientific and Technical Information of China (English)

    何洪文; 余晓江; 孙逢春

    2004-01-01

    From electric circuit theory view, a system model of series hybrid electric vehicle was built which uses engine-generator and battery pack as its on-board energy source in this paper. Based on the analysis for the constant power work mode and constant bus voltage work mode of engine-generator, a third work mode was put forward which combined the advantages of constant power and constant bus voltage work modes. The new work mode is reasonable to keep the battery in good working conditions and to extend its life. Also the working conditions of engine can be bettered to get low pollution and high efficiency.

  20. Hybrid-impulsive second order sliding mode control: Lyapunov approach

    NARCIS (Netherlands)

    Shtessel, Y.; Glumineau, A.; Plestan, F.; Weiss, M.

    2013-01-01

    A perturbed nonlinear system of relative degree two controlled by discontinuous-impulsive feedbacks is studied. The hybrid-impulsive terms serve to drive instantaneously the system trajectories to the origin or to its small vicinity. In particular, impulsive-twisting control exhibits an uniform exac

  1. Hybrid-impulsive second order sliding mode control: Lyapunov approach

    NARCIS (Netherlands)

    Shtessel, Y.; Glumineau, A.; Plestan, F.; Weiss, M.

    2013-01-01

    A perturbed nonlinear system of relative degree two controlled by discontinuous-impulsive feedbacks is studied. The hybrid-impulsive terms serve to drive instantaneously the system trajectories to the origin or to its small vicinity. In particular, impulsive-twisting control exhibits an uniform

  2. Mode hybridization and conversion in silicon-on-insulator nanowires with angled sidewalls.

    Science.gov (United States)

    Dai, Daoxin; Zhang, Ming

    2015-12-14

    The mode property and light propagation in a tapered silicon-on-insulator (SOI) nanowire with angled sidewalls is analyzed. Mode hybridization is observed and mode conversion between the TM fundamental mode and higher-order TE modes happens when light propagates in a waveguide taper which is used very often in the design of photonic integrated devices. This mode conversion ratio is possible to be very high (even close to 100%) when the taper is long enough to be adiabatic, which might be useful for some applications of multimode photonics. When the mode conversion is undesired to avoid any excess loss as well as crosstalk for photonic integrated circuits, one can depress the mode conversion by compensating the vertical asymmetry in the way of reducing the sidewall angle or introducing an optimal refractive index for the upper-cladding. It is also possible to eliminate the undesired mode conversion almost and improve the desired mode conversion greatly by introducing an abrupt junction connecting two sections with different widths to jump over the mode hybridization region.

  3. The speedster-EXD - A new event-triggered hybrid CMOS x-ray detector

    CERN Document Server

    Griffith, Christopher V; Prieskorn, Zachary R; Burrows, David N

    2014-01-01

    We present preliminary characterization of the Speedster-EXD, a new event driven hybrid CMOS detector (HCD) developed in collaboration with Penn State University and Teledyne Imaging Systems. HCDs have advantages over CCDs including lower susceptibility to radiation damage, lower power consumption, and faster read-out time to avoid pile-up. They are deeply depleted and able to detect x-rays down to approximately 0.1 keV. The Speedster-EXD has additional in-pixel features compared to previously published HCDs including: (1) an in-pixel comparator that enables read out of only the pixels with signal from an x-ray event, (2) four different gain modes to optimize either full well capacity or energy resolution, (3) in-pixel CDS subtraction to reduce read noise, and (4) a low-noise, high-gain CTIA amplifier to eliminate interpixel capacitance crosstalk. When using the comparator feature, the user can set a comparator threshold and only pixels above the threshold will be read out. This feature can be run in two mode...

  4. Polarization switch of four-wave mixing in large mode area hybrid photonic crystal fibers

    DEFF Research Database (Denmark)

    Petersen, Sidsel Rübner; Alkeskjold, Thomas Tanggaard; Olausson, Christina Bjarnal Thulin;

    2015-01-01

    Degenerate spontaneous four-wave mixing is considered in a large mode area hybrid photonic crystal fiber. Numerical and experimental results show birefringence assisted four-wave mixing for a certain polarization state of the pump field. The parametric gain can be turned on and off by switching...... the polarization state of the pump field between the two principal axis of the hybrid photonic crystal fiber. (C) 2015 Optical Society of America...

  5. Polarization switch of four-wave mixing in large mode area hybrid photonic crystal fibers.

    Science.gov (United States)

    Petersen, Sidsel R; Alkeskjold, Thomas T; Olausson, Christina B; Lægsgaard, Jesper

    2015-02-15

    Degenerate spontaneous four-wave mixing is considered in a large mode area hybrid photonic crystal fiber. Numerical and experimental results show birefringence assisted four-wave mixing for a certain polarization state of the pump field. The parametric gain can be turned on and off by switching the polarization state of the pump field between the two principal axis of the hybrid photonic crystal fiber.

  6. Hybrid algorithm for accelerating the double series of Floquet vector modes

    Institute of Scientific and Technical Information of China (English)

    LI Weidong; HONG Wei; HAO Zhangcheng; ZHOU Houxing

    2006-01-01

    In this paper, a hybrid algorithm for accelerating the double series of Floquet vector modes arising in the analysis of frequency selective surfaces (FSS) is presented. The asymptotic terms with slow convergence in the double series are first accelerated by Poisson transformation and Ewald method, and then the remained series is accelerated by Shank transformation. It results in significant savings in memory and computing time. Numerical examples verify the validity of the hybrid acceleration algorithm.

  7. Control and fault diagnosis based sliding mode observer of a multicellular converter: Hybrid approach

    KAUST Repository

    Benzineb, Omar

    2013-01-01

    In this article, the diagnosis of a three cell converter is developed. The hybrid nature of the system represented by the presence of continuous and discrete dynamics is taken into account in the control design. The idea is based on using a hybrid control and an observer-type sliding mode to generate residuals from the observation errors of the system. The simulation results are presented at the end to illustrate the performance of the proposed approach. © 2013 FEI STU.

  8. Comparison on welding mode characteristics of arc heat source for heat input control in hybrid welding of aluminum alloy

    Science.gov (United States)

    Song, Moo-Keun; Kim, Jong-Do; Oh, Jae-Hwan

    2015-03-01

    Presently in shipbuilding, transportation and aerospace industries, the potential to apply welding using laser and laser-arc hybrid heat sources is widely under research. This study has the purpose of comparing the weldability depending on the arc mode by varying the welding modes of arc heat sources in applying laser-arc hybrid welding to aluminum alloy and of implementing efficient hybrid welding while controlling heat input. In the experimental study, we found that hybrid welding using CMT mode produced deeper penetration and sounder bead surface than those characteristics produced during only laser welding, with less heat input compared to that required in pulsed arc mode.

  9. Dust-cyclotron and dust-lower-hybrid modes in self-gravitating magnetized dusty plasmas

    Indian Academy of Sciences (India)

    A K Banerjee; M N Alam; A A Mamun

    2003-07-01

    Theoretical investigation has been made on two different ultra-low-frequency electrostatic modes, namely, dust-cyclotron mode and dust-lower-hybrid mode, propagating perpendicular to the external magnetic field, in a self-gravitating magnetized two-fluid dusty plasma system. It has been shown that the effect of the self-gravitational force, acting on both dust grains and ions, significantly modifies the dispersion properties of these two electrostatic modes. The implications of these results to some space and astrophysical dusty plasma systems, especially to planetary ring-systems and cometary tails, are briefly mentioned.

  10. Mode transition coordinated control for a compound power-split hybrid car

    Science.gov (United States)

    Wang, Chen; Zhao, Zhiguo; Zhang, Tong; Li, Mengna

    2017-03-01

    With a compound power-split transmission directly connected to the engine in hybrid cars, dramatic fluctuations in engine output torque result in noticeable jerks when the car is in mode transition from electric drive mode to hybrid drive mode. This study designed a mode transition coordinated control strategy, and verified that strategy's effectiveness with both simulations and experiments. Firstly, the mode transition process was analyzed, and ride comfort issues during the mode transition process were demonstrated. Secondly, engine ripple torque was modeled using the measured cylinder pumping pressure when the engine was not in operation. The complete dynamic plant model of the power-split hybrid car was deduced, and its effectiveness was validated by a comparison of experimental and simulation results. Thirdly, a coordinated control strategy was designed to determine the desired engine torque, motor torque, and the moment of fuel injection. Active damping control with two degrees of freedom, based on reference output shaft speed estimation, was designed to mitigate driveline speed oscillations. Carrier torque estimation based on transmission kinematics and dynamics was used to suppress torque disturbance during engine cranking. The simulation and experimental results indicate that the proposed strategy effectively suppressed vehicle jerks and improved ride comfort during mode transition.

  11. Tailoring the parametric gain in large mode area hybrid photonic crystal fibers

    DEFF Research Database (Denmark)

    Petersen, Sidsel Rübner; Lægsgaard, Jesper; Alkeskjold, Thomas Tanggaard

    2013-01-01

    The spectral width of parametric gain peaks due to degenerate four-wave mixing is investigated numerically in large-mode-area hybrid photonic crystal fibers. The width is varied for a maintained pump wavelength and gain maximum position by tailoring the dispersion.......The spectral width of parametric gain peaks due to degenerate four-wave mixing is investigated numerically in large-mode-area hybrid photonic crystal fibers. The width is varied for a maintained pump wavelength and gain maximum position by tailoring the dispersion....

  12. Conversion of electrostatic upper hybrid emissions to electromagnetic O and X mode waves in the Earth's magnetosphere

    Energy Technology Data Exchange (ETDEWEB)

    Budden, K.G.; Jones, D.

    1987-02-01

    The linear conversion of electrostatic upper hybrid emissions via the Z mode to electromagnetic ordinary (O) mode waves has for some time been invoked for the source of Terrestrial and Saturnian myriametric and Jovian kilometric radiations. The conversion occurs by virtue of the emissions' propagation in concentration gradients, and for it to be efficient it is necessary for the gradient to be normal to the ambient magnetic field. Suitable concentration gradients are believed to occur at the plasmapause and at the magnetopause. Ray theory predicts only O mode production whereas full wave theory in a cold plasma shows that both O and X (extraordinary) mode are produced, their relative intensities depending on the plasma parameters. Full wave theory in a warm plasma, besides yielding more accurate information on the O and X modes also provides an insight into the effect of conversion on the source plasma wave. Results obtained from these three levels of theory are compared using plasma parameters derived from wave experiments on spacecraft.

  13. Hybrid Fuzzy Sliding Mode Controller for Timedelay System

    OpenAIRE

    Yadav, N K; R. K. Singh,

    2013-01-01

    This paper is concerned with the problems of stability analysis and stabilization control design for a class of discrete-time T-S fuzzy systems with state-delay for multi-input and multi-output. The nonlinear fuzzy controller helps to overcome the problems of the ill - defined model of the systems, which are creating the undesirable performance. . Here sliding surface is being designed for error function of nonlinear system and sliding mode control is being designed here. The swit...

  14. Mode Shift Control for a Hybrid Heavy-Duty Vehicle with Power-Split Transmission

    Directory of Open Access Journals (Sweden)

    Kun Huang

    2017-02-01

    Full Text Available Given that power-split transmission (PST is considered to be a major powertrain technology for hybrid heavy-duty vehicles (HDVs, the development and application of PST in the HDVs make mode shift control an essential aspect of powertrain system design. This paper presents a shift schedule design and torque control strategy for a hybrid HDV with PST during mode shift, intended to reduce the output torque variation and improve the shift quality (SQ. Firstly, detailed dynamic models of the hybrid HDV are developed to analyze the mode shift characteristics. Then, a gear shift schedule calculation method including a dynamic shift schedule and an economic shift schedule is provided. Based on the dynamic models and the designed shift schedule, a mode shift performance simulator is built using MATLAB/Simulink, and simulations are carried out. Through analysis of the dynamic equations, it is seen that the inertia torques of the motor–generator lead to the occurrence of transition torque. To avoid the unwanted transition torque, we use a mode shift control strategy that coordinates the motor–generator torque to compensate for the transition torque. The simulation and experimental results demonstrate that the output torque variation during mode shift is effectively reduced by the proposed control strategy, thereby improving the SQ.

  15. Fuzzy-logic-based hybrid locomotion mode classification for an active pelvis orthosis: Preliminary results.

    Science.gov (United States)

    Yuan, Kebin; Parri, Andrea; Yan, Tingfang; Wang, Long; Munih, Marko; Vitiello, Nicola; Wang, Qining

    2015-01-01

    In this paper, we present a fuzzy-logic-based hybrid locomotion mode classification method for an active pelvis orthosis. Locomotion information measured by the onboard hip joint angle sensors and the pressure insoles is used to classify five locomotion modes, including two static modes (sitting, standing still), and three dynamic modes (level-ground walking, ascending stairs, and descending stairs). The proposed method classifies these two kinds of modes first by monitoring the variation of the relative hip joint angle between the two legs within a specific period. Static states are then classified by the time-based absolute hip joint angle. As for dynamic modes, a fuzzy-logic based method is proposed for the classification. Preliminary experimental results with three able-bodied subjects achieve an off-line classification accuracy higher than 99.49%.

  16. Hybrid empirical mode decomposition- ARIMA for forecasting exchange rates

    Science.gov (United States)

    Abadan, Siti Sarah; Shabri, Ani; Ismail, Shuhaida

    2015-02-01

    This paper studied the forecasting of monthly Malaysian Ringgit (MYR)/ United State Dollar (USD) exchange rates using the hybrid of two methods which are the empirical model decomposition (EMD) and the autoregressive integrated moving average (ARIMA). MYR is pegged to USD during the Asian financial crisis causing the exchange rates are fixed to 3.800 from 2nd of September 1998 until 21st of July 2005. Thus, the chosen data in this paper is the post-July 2005 data, starting from August 2005 to July 2010. The comparative study using root mean square error (RMSE) and mean absolute error (MAE) showed that the EMD-ARIMA outperformed the single-ARIMA and the random walk benchmark model.

  17. Development of a wearable exoskeleton rehabilitation system based on hybrid control mode

    Directory of Open Access Journals (Sweden)

    Yi Long

    2016-10-01

    Full Text Available Lower limb rehabilitation exoskeletons usually help patients walk based on fixed gait trajectories. However, it is not suitable for unilateral lower limb disorders. In this article, a hybrid training mode is proposed to be applied in rehabilitation for unilateral lower limb movement disorders. The hybrid training includes two modes, that is, the passive training mode and the active assist mode. At an early stage of the rehabilitation therapy, the passive training mode is utilized, in which microelectromechanical systems-based attitude and heading reference system is used to collect the gait trajectory of the healthy limb. The exoskeleton on the unhealthy limb will be driven to track the joint trajectory of the healthy limb. If the patient’s abilities recovered, the rehabilitation system can be switched to the active assist mode. Two force sensors are imbedded into the interface on the thigh to measure the interaction information in order to detect the patient’s initiative walking intention. In the active mode, the walking gait trajectory is modified and generated based on the gait trajectory of the healthy side via the attitude and heading reference system. In this article, a position close control loop is designed to drive the mechanical leg to help the unhealthy limb walk. Laboratory experiments are performed on a healthy human subject to illustrate the proposed approach. Experimental results show that the proposed method can be applied and extended in the passive and active rehabilitation mode for the unilateral lower limb disorders.

  18. Tamm-plasmon and surface-plasmon hybrid-mode based refractometry in photonic bandgap structures.

    Science.gov (United States)

    Das, Ritwick; Srivastava, Triranjita; Jha, Rajan

    2014-02-15

    The transverse magnetic (TM) polarized hybrid modes formed as a consequence of coupling between Tamm plasmon polariton (TM-TPP) mode and surface plasmon polariton (SPP) mode exhibit interesting dispersive features for realizing a highly sensitive and accurate surface plasmon resonance (SPR) sensor. We found that the TM-TPP modes, formed at the interface of distributed Bragg reflector and metal, are strongly dispersive as compared to SPP modes at optical frequencies. This causes an appreciably narrow interaction bandwidth between TM-TPP and SPP modes, which leads to highly accurate sensing. In addition, appropriate tailoring of dispersion characteristics of TM-TPP as well as SPP modes could ensure high sensitivity of a novel SPR platform. By suitably designing the Au/TiO₂/SiO₂-based geometry, we propose a TM-TPP/SPP hybrid-mode sensor and achieve a sensitivity ≥900  nm/RIU with high detection accuracy (≥30  μm⁻¹) for analyte refractive indices varying between 1.330 and 1.345 in 600-700 nm wavelength range. The possibility to achieve desired dispersive behavior in any spectral band makes the sensing configuration an extremely attractive candidate to design sensors depending on the availability of optical sources.

  19. Dynamically configurable hybridization of plasmon modes in nanoring dimer arrays

    Science.gov (United States)

    Zhang, Lei; Dong, Zhaogang; Wang, Ying Min; Liu, Yan Jun; Zhang, Shuang; Yang, Joel Kwang Wei; Qiu, Cheng-Wei

    2015-07-01

    We present a novel strategy capable of dynamically configuring the plasmon-induced transparency (PIT) effect with a polarization-dependent controllability based on a nanoring dimer array. The controllable coupling strength between the superradiant and subradiant modes is due to the polarization-dependent field distributions. It is shown that this dynamically controlled PIT is realized with a modulation depth as high as 95%, and a linear dependence of the coupling strength on polarization angle is deduced using a coupled-oscillator model. We believe that our results will inspire further exciting achievements that utilize various polarization states of the electromagnetic wave and pave a way towards applications using PIT with dynamic controllability such as slow light, optical nonlinearities and chemical/bio-sensing.We present a novel strategy capable of dynamically configuring the plasmon-induced transparency (PIT) effect with a polarization-dependent controllability based on a nanoring dimer array. The controllable coupling strength between the superradiant and subradiant modes is due to the polarization-dependent field distributions. It is shown that this dynamically controlled PIT is realized with a modulation depth as high as 95%, and a linear dependence of the coupling strength on polarization angle is deduced using a coupled-oscillator model. We believe that our results will inspire further exciting achievements that utilize various polarization states of the electromagnetic wave and pave a way towards applications using PIT with dynamic controllability such as slow light, optical nonlinearities and chemical/bio-sensing. Electronic supplementary information (ESI) available: Method, mode supported by single nanoring, transmittance spectrum of single nanoring, comparison of transmittance spectra simulated under different illumination angles, diffraction coupling in the proposed nanoring dimer system, and the coupled Lorentz oscillator model and parameters

  20. Generation of ordinary mode electromagnetic radiation near the upper hybrid frequency in the magnetosphere

    Science.gov (United States)

    Ashour-Abdalla, M.; Okuda, H.

    1984-01-01

    It is shown by means of plasma numerical simulations that long-wavelength ordinary mode electromagnetic radiation can be generated from short-wavelength electrostatic waves near the upper hybrid resonance frequency in an inhomogeneous plasma. A possible relation of this process to nonthermal continuum radiation in the magnetosphere is discussed.

  1. Optimal air-supply mode of hybrid system with radiant cooling and dedicated outdoor air

    Institute of Scientific and Technical Information of China (English)

    丁研; 田喆; 朱能

    2015-01-01

    The hybrid system with radiant cooling and dedicated outdoor air not only possesses high energy efficiency, but also creates a healthy and comfortable indoor environment. Indoor air quality will be improved by the dedicated outdoor air system (DOAS) and indoor thermal comfort can be enhanced by the radiant cooling system (RCS). The optimal air-supply mode of the hybrid system and the corresponding design approach were investigated. A full-scale experimental chamber with various air outlets and the ceiling radiant cooling panels (CRCP) was designed and established. The performances of different air-supply modes along with CRCPs were analyzed by multi-index evaluations. Preliminary investigations were also conducted on the humidity stratification and the control effect of different airflow modes to prevent condensation on CRCP. The overhead supply air is recommended as the best combination mode for the hybrid system after comprehensive comparison of the experiment results. The optimal proportion of CRCP accounting for the total cooling capacities in accord with specific cooling loads is found, which may provide valuable reference for the design and operation of the hybrid system.

  2. Bifurcation of resistive wall mode dynamics predicted by magnetohydrodynamic-kinetic hybrid theory

    Energy Technology Data Exchange (ETDEWEB)

    Yang, S. X.; Wang, Z. X., E-mail: zxwang@dlut.edu.cn [Key Laboratory of Materials Modification by Beams of the Ministry of Education, School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China); Wang, S.; Hao, G. Z., E-mail: haogz@swip.ac.cn; Song, X. M.; Wang, A. K. [Southwestern Institute of Physics, P.O.Box 432, Chengdu 610041 (China); Liu, Y. Q. [Culham Centre for Fusion Energy, Culham Science Centre, Abingdon OX14 3DB (United Kingdom); Southwestern Institute of Physics, P.O.Box 432, Chengdu 610041 (China)

    2015-09-15

    The magnetohydrodynamic-kinetic hybrid theory has been extensively and successfully applied for interpreting experimental observations of macroscopic, low frequency instabilities, such as the resistive wall mode, in fusion plasmas. In this work, it is discovered that an analytic version of the hybrid formulation predicts a bifurcation of the mode dynamics while varying certain physical parameters of the plasma, such as the thermal particle collisionality or the ratio of the thermal ion to electron temperatures. This bifurcation can robustly occur under reasonably large parameter spaces as well as with different assumptions, for instance, on the particle collision model. Qualitatively similar bifurcation features are also observed in full toroidal computations presented in this work, based on a non-perturbative hybrid formulation.

  3. Detecting Urban Transport Modes Using a Hybrid Knowledge Driven Framework from GPS Trajectory

    Directory of Open Access Journals (Sweden)

    Rahul Deb Das

    2016-11-01

    Full Text Available Transport mode information is essential for understanding people’s movement behavior and travel demand estimation. Current approaches extract travel information once the travel is complete. Such approaches are limited in terms of generating just-in-time information for a number of mobility based applications, e.g., real time mode specific patronage estimation. In order to detect the transport modalities from GPS trajectories, various machine learning approaches have already been explored. However, the majority of them produce only a single conclusion from a given set of evidences, ignoring the uncertainty of any mode classification. Also, the existing machine learning approaches fall short in explaining their reasoning scheme. In contrast, a fuzzy expert system can explain its reasoning scheme in a human readable format along with a provision of inferring different outcome possibilities, but lacks the adaptivity and learning ability of machine learning. In this paper, a novel hybrid knowledge driven framework is developed by integrating a fuzzy logic and a neural network to complement each other’s limitations. Thus the aim of this paper is to automate the tuning process in order to generate an intelligent hybrid model that can perform effectively in near-real time mode detection using GPS trajectory. Tests demonstrate that a hybrid knowledge driven model works better than a purely knowledge driven model and at per the machine learning models in the context of transport mode detection.

  4. Mode-evolution-based polarization rotation and coupling between silicon and hybrid plasmonic waveguides

    Science.gov (United States)

    Kim, Sangsik; Qi, Minghao

    2015-12-01

    Hybrid plasmonic (HP) modes allow strong optical field confinement and simultaneously low propagation loss, offering a potentially compact and efficient platform for on-chip photonic applications. However, their implementation is hampered by the low coupling efficiency between dielectric guided modes and HP modes, caused by mode mismatch and polarization difference. In this work, we present a mode-evolution-based polarization rotation and coupling structure that adiabatically rotates the TE mode in a silicon waveguide and couples it to the HP mode in a strip silicon-dielectric-metal waveguide. Simulation shows that high coupling factors of 92%, 78%, 75%, and 73% are achievable using Ag, Au, Al, and Cu as the metal cap, respectively, at a conversion length of about 5 μm. For an extremely broad wavelength range of 1300-1800 nm, the coupling factor is >64% with a Ag metal cap, and the total back-reflection power, including all the mode reflections and backscattering, is below -40 dB, due to the adiabatic mode transition. Our device does not require high-resolution lithography and is tolerant to fabrication variations and imperfections. These attributes together make our device suitable for optical transport systems spanning all telecommunication bands.

  5. Full wave simulations of fast wave mode conversion and lower hybrid wave propagation in tokamaks

    DEFF Research Database (Denmark)

    Wright, J.C.; Bonoli, P.T.; Brambilla, M.;

    2004-01-01

    Fast wave (FW) studies of mode conversion (MC) processes at the ion-ion hybrid layer in toroidal plasmas must capture the disparate scales of the FW and mode converted ion Bernstein and ion cyclotron waves. Correct modeling of the MC layer requires resolving wavelengths on the order of k(perpendi......Fast wave (FW) studies of mode conversion (MC) processes at the ion-ion hybrid layer in toroidal plasmas must capture the disparate scales of the FW and mode converted ion Bernstein and ion cyclotron waves. Correct modeling of the MC layer requires resolving wavelengths on the order of k......). Two full wave codes, a massively-parallel-processor (MPP) version of the TORIC-2D finite Larmor radius code [M. Brambilla, Plasma Phys. Controlled Fusion 41, 1 (1999)] and also an all orders spectral code AORSA2D [E. F. Jaeger , Phys. Plasmas 9, 1873 (2002)], have been developed which for the first......)] to gain new understanding into the nature of FWMC in tokamaks. The massively-parallel-processor version of TORIC is also now capable of running with sufficient resolution to model planned lower hybrid range of frequencies experiments in the Alcator C-Mod. (C) 2004 American Institute of Physics....

  6. Hard X-rays for processing hybrid organic-inorganic thick films.

    Science.gov (United States)

    Jiang, Yu; Carboni, Davide; Pinna, Alessandra; Marmiroli, Benedetta; Malfatti, Luca; Innocenzi, Plinio

    2016-01-01

    Hard X-rays, deriving from a synchrotron light source, have been used as an effective tool for processing hybrid organic-inorganic films and thick coatings up to several micrometres. These coatings could be directly modified, in terms of composition and properties, by controlled exposure to X-rays. The physico-chemical properties of the coatings, such as hardness, refractive index and fluorescence, can be properly tuned using the interaction of hard X-rays with the sol-gel hybrid films. The changes in the microstructure have been correlated especially with the modification of the optical and the mechanical properties. A relationship between the degradation rate of the organic groups and the rise of fluorescence from the hybrid material has been observed; nanoindentation analysis of the coatings as a function of the X-ray doses has shown a not linear dependence between thickness and film hardness.

  7. Free chattering hybrid sliding mode control for a class of non-linear systems

    DEFF Research Database (Denmark)

    Khooban, Mohammad-Hassan; Niknam, Taher; Blaabjerg, Frede

    2016-01-01

    In current study, in order to find the control of general uncertain nonlinear systems, a new optimal hybrid control approach called Optimal General Type II Fuzzy Sliding Mode (OGT2FSM) is presented. In order to estimate unknown nonlinear activities in monitoring dynamic uncertainties, the benefits...... on the same topic, which are an Adaptive Interval Type-2 Fuzzy Logic Controller (AGT2FLC) and Conventional Sliding Mode Controller (CSMC), to assess the efficiency of the suggested controller. The suggested control scheme is finally used to the Electric Vehicles type as a case study. Results of simulation...

  8. Mode of inheritance for fruit firmness in tomato hybrids of F1 generation (Lycoperscum esculentum Mill.

    Directory of Open Access Journals (Sweden)

    Sušić Zoran

    2000-01-01

    Full Text Available Present day program for tomato selection are aimed at creating the genotypes with firm fruit. The fruits with this quality surfer from minor injuries while being harvested and transported, which directly affects their better consumption purpose. By crossing seven divergent tomato genotypes that differed among themselves in fruit firmness, and by applying the method of full diallel without reciprocal crossings, we obtained 21 hybrids of F1 generation. Upon analyzing the components of the genetic variance we found out that dominant genes prevailed in inheriting this feature. Considering all the crossing combinations together, it could be concluded that super dominance was the mode of inheritance recorded in Fl generation. The hybrid combination obtained by crossing the two hybrids with the best general combining ability (V-100 x No-10 was characterized by the best specific combining ability. .

  9. Diverse Strategies for Diverse Learners: Action Learning in a Hybrid Mode

    Directory of Open Access Journals (Sweden)

    Esmarie Strydom

    2007-08-01

    Full Text Available This paper describes an action research study during which a flexible or hybrid approach to delivering an Information and Communication Technology competency course is implemented in the preparation of student teachers. The course incorporates Web-based course-content delivery, face-to-face classroom meetings to satisfy the need for human interaction, a variety of assessment methods, as well as recognition of prior learning. The objectives are to accommodate learning diversity, make learning focused and achievable for each learner, allow for intervention if the learning outcomes are not met, and focus on and guide the learning process, i.e. teach learners how to learn. This paper reports on the perspectives and experiences of two groups of first year learners, namely student teachers who attended a hybrid ICT course and first year learners who attended an e-learning ICT course. It was found that the success rate of the hybrid mode ICT course was significantly higher than that of the similar e-learning ICT course. The hybrid mode ICT course also enabled the learners to become self-directed to a higher degree.

  10. Diverse Strategies for Diverse Learners: Action Learning in a Hybrid Mode

    Directory of Open Access Journals (Sweden)

    Esmarie Strydom

    2007-08-01

    Full Text Available This paper describes an action research study during which a flexible or hybrid approach to delivering an Information and Communication Technology competency course is implemented in the preparation of student teachers. The course incorporates Web-based course-content delivery, face-to-face classroom meetings to satisfy the need for human interaction, a variety of assessment methods, as well as recognition of prior learning. The objectives are to accommodate learning diversity, make learning focused and achievable for each learner, allow for intervention if the learning outcomes are not met, and focus on and guide the learning process, i.e. teach learners how to learn. This paper reports on the perspectives and experiences of two groups of first year learners, namely student teachers who attended a hybrid ICT course and first year learners who attended an e-learning ICT course. It was found that the success rate of the hybrid mode ICT course was significantly higher than that of the similar e-learning ICT course. The hybrid mode ICT course also enabled the learners to become self-directed to a higher degree.

  11. Stability of hybrid modes of a single-component electron plasma containing an admixture of background gas ions

    Science.gov (United States)

    Yeliseyev, Yu. N.

    2014-05-01

    The spectrum of eigenmodes of a waveguide completely filled with a cold electron plasma containing a small admixture of ions produced due to electron-impact ionization of background gas atoms is calculated numerically. The calculations were performed within the entire range of allowable values of the radial electric and longitudinal magnetic fields for both magnetized and unmagnetized ions by using the earlier derived nonlocal dispersion relation [Plasma Phys. Rep. 36, 563 (2010)]. The spectrum consists of three families of electron modes with frequencies equal to the Doppler-shifted upper and lower hybrid frequencies and modified ion cyclotron (MIC) modes. When the Doppler shift caused by electron rotation in the crossed electric and magnetic fields compensates for the hybrid frequency, the electron modes become low-frequency modes and interact with the ion modes. For m = 1, only the lower hybrid modes can be low-frequency ones, whereas at m ≥ 2, both lower and upper hybrid modes can be low-frequency ones. The spectrum of modes having the azimuthal number m = 2 is thoroughly analyzed. It is shown that, in this case, the lower hybrid modes behave similar to the m = 1 modes. The dispersion curves of the upper hybrid modes intersect with all harmonics of the MIC frequency (positive, negative, and zero) and are unstable in the vicinities of the intersections. The maximum value of the instability growth rate is several times higher than the ion plasma frequency. The MIC modes are unstable within a wide range of the field strengths, and their growth rates are two orders of magnitude slower. Instabilities are caused by the relative motion of electrons and ions (the transverse current) and the anisotropy of the ion distribution function.

  12. Effort of lower hybrid current drive experiments toward to H-mode in EAST

    Science.gov (United States)

    Ding, B. J.; Li, M. H.; Liu, F. K.; Shan, J. F.; Li, Y. C.; Wang, M.; Liu, L.; Zhao, L. M.; Yang, Y.; Wu, Z. G.; Feng, J. Q.; Hu, H. C.; Jia, H.; Cheng, M.; Zang, Q.; Lyu, B.; Duan, Y. M.; Lin, S. Y.; Wu, J. H.; Hillairet, J.; Ekedahl, A.; Peysson, Y.; Goniche, M.; Tuccillo, A. A.; Cesario, R.; Amicucci, L.; Shen, B.; Gong, X. Z.; Xu, G. S.; Zhao, H. L.; Hu, L. Q.; Li, J. G.; Wan, B. N.; EAST Team

    2017-02-01

    Lower hybrid current drive (LHCD) is an effective tool to achieve high confinement (H-mode) plasma in EAST. To utilize LHCD for accessing H-mode plasma, efforts have been made to improve LHW (lower hybrid wave)-plasma coupling and current drive capability at high density. Improved LHW-plasma coupling by means of local gas puffing and gas puffing from the electron side is routinely used during EAST operation with LHCD. High density experiments suggest that low recycling and high LH frequency are preferred for LHCD experiments at high density, consistent with previous results in other machines. The effect of LHCD on the current profile in EAST demonstrates that it is possible to control the plasma profile by optimizing the LHW spectrum. Repeatable H-mode plasma was obtained by LHCD and the maximum density during H-mode with the combination of 2.45 GHz and 4.6 GHz LH waves was up to 4.5  ×  1019 m-3.

  13. Hybrid mode-locked fiber ring laser using graphene and charcoal nanoparticles as saturable absorbers

    Science.gov (United States)

    Hu, Hongyu; Zhang, Xiang; Li, Wenbo; Dutta, Niloy K.

    2016-05-01

    A fiber ring laser which implements hybrid mode locking technique has been proposed and experimentally demonstrated to generate pulse train at 20 GHz repetition rate with ultrashort pulse width. Graphene and charcoal nano-particles acting as passive mode lockers are inserted into a rational harmonic mode-locked fiber laser to improve the performance. With graphene saturable absorbers, the pulse duration is shortened from 5.3 ps to 2.8 ps, and with charcoal nano-particles, it is shortened to 3.2 ps. The RF spectra show that supermode noise can be removed in the presence of the saturable absorbers. Numerical simulation of the pulse transmission has also been carried out, which shows good agreement with the experimental results.

  14. Dispersion peculiarities of hybrid modes in a uniaxial waveguide filled by a gyroelectromagnetic medium

    CERN Document Server

    Tuz, Vladimir R; Fesenko, Volodymyr I; Sun, Hong-Bo; Shulga, Valeriy M; Wei, Han

    2016-01-01

    Extraordinary dispersion features of a circular waveguide filled by a longitudinally magnetized composite gyroelectromagnetic medium are studied. The composite medium is considered to be constructed by juxtaposition together of magnetic and semiconductor layers providing all characteristic dimensions of the resulting multilayered system are much smaller than the wavelength in the corresponding part of the composite medium. The waveguide dispersion equation and its eigenmodes are derived. The mode classification is made in a standard manner so that the guided modes are sorted into a class of hybrid HE and EH waves in terms of their unique dispersion characteristics. The numerical results are obtained in the band near the frequencies of corresponding resonances in constitutive materials of the composite medium, and they show that the modes behaviors become to be quite diverse due to manifestation of a strong combined geometrical and material dispersion related to the waveguide parameters and gyroelectromagnetic...

  15. Hybrid mode-locked erbium-doped all-fiber soliton laser with a distributed polarizer.

    Science.gov (United States)

    Chernykh, D S; Krylov, A A; Levchenko, A E; Grebenyukov, V V; Arutunyan, N R; Pozharov, A S; Obraztsova, E D; Dianov, E M

    2014-10-10

    A soliton-type erbium-doped all-fiber ring laser hybrid mode-locked with a co-action of arc-discharge single-walled carbon nanotubes (SWCNTs) and nonlinear polarization evolution (NPE) is demonstrated. For the first time, to the best of our knowledge, boron nitride-doped SWCNTs were used as a saturable absorber for passive mode-locking initiation. Moreover, the NPE was introduced through the implementation of the short-segment polarizing fiber. Owing to the NPE action in the laser cavity, significant pulse length shortening as well as pulse stability improvement were observed as compared with a SWCNTs-only mode-locked laser. The shortest achieved pulse width of near transform-limited solitons was 222 fs at the output average power of 9.1 mW and 45.5 MHz repetition frequency, corresponding to the 0.17 nJ pulse energy.

  16. Hybrid Systems of Distributed Generation with Renewable Sources: Modeling and Analysis of Their Operational Modes in Electric Power System

    Directory of Open Access Journals (Sweden)

    A. Gashimov

    2013-01-01

    Full Text Available The paper considers problems pertaining to modeling and simulation of operational hybrid system modes of the distributed generation comprising conventional sources – modular diesel generators, gas-turbine power units; and renewable sources – wind and solar power plants. Operational modes of the hybrid system have been investigated under conditions of electrical connection with electric power system and in case of its isolated operation. As a consequence

  17. The Radio and X-ray Mode-Switching Pulsar PSR B0943+10

    Science.gov (United States)

    Mereghetti, Sandro; Rigoselli, Michela

    2017-09-01

    Observations obtained in the last years challenged the widespread notion that rotation-powered neutron stars are steady X-ray emitters. Besides a few allegedly rotation-powered neutron stars that showed `magnetar-like' variability, a particularly interesting case is that of PSR B0943+10. Recent observations have shown that this pulsar, well studied in the radio band where it alternates between a bright and a quiescent mode, displays significant X-ray variations, anticorrelated in flux with the radio emission. The study of such synchronous radio/X-ray mode switching opens a new window to investigate the processes responsible for the pulsar radio and high-energy emission. Here we review the main X-ray properties of PSR B0943+10 derived from recent coordinated X-ray and radio observations.

  18. S-band linac-based X-ray source with {pi}/2-mode electron linac

    Energy Technology Data Exchange (ETDEWEB)

    Deshpande, Abhay, E-mail: abhay@post.kek.jp [Department of Accelerator Science, School of High Energy Accelerator Science, Graduate University for Advanced Studies, Shonan International Village, Hayama, Miura, Kanagawa 240-0193 (Japan); Society for Applied Microwave Electronic Engineering and Research (SAMEER), R and D Laboratory of the Government of India, IIT Campus, Powai, Mumbai 400 076 (India); Araki, Sakae [High Energy Accelerator Research Organization, 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan); Dixit, Tanuja [Society for Applied Microwave Electronic Engineering and Research (SAMEER), R and D Laboratory of the Government of India, IIT Campus, Powai, Mumbai 400 076 (India); Fukuda, Masafumi [High Energy Accelerator Research Organization, 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan); Krishnan, R; Pethe, Sanjay [Society for Applied Microwave Electronic Engineering and Research (SAMEER), R and D Laboratory of the Government of India, IIT Campus, Powai, Mumbai 400 076 (India); Sakaue, Kazuyuki [Waseda University, Shinjuku-ku, Tokyo 169-8555 (Japan); Terunuma, Nobuhiro; Urakawa, Junji [High Energy Accelerator Research Organization, 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan); Washio, Masakazu [Waseda University, Shinjuku-ku, Tokyo 169-8555 (Japan)

    2011-05-01

    The activities with the compact X-ray source are attracting more attention, particularly for the applications of the source in medical fields. We propose the fabrication of a compact X-ray source using the SAMEER electron linear accelerator and the KEK laser undulator X-ray source (LUCX) technologies. The linac developed at SAMEER is a standing wave side-coupled S-band linac operating in the {pi}/2 mode. In the proposed system, a photocathode RF gun will inject bunches of electrons in the linac to accelerate and achieve a high-energy, low-emittance beam. This beam will then interact with the laser in the laser cavity to produce X-rays of a type well suited for various applications. The side-coupled structure will make the system more compact, and the {pi}/2 mode of operation will enable a high repetition rate operation, which will help to increase the X-ray yield.

  19. The Radio and X-ray Mode-Switching Pulsar PSR B0943+10

    Indian Academy of Sciences (India)

    Sandro Mereghetti; Michela Rigoselli

    2017-09-01

    Observations obtained in the last years challenged the widespread notion that rotation-powered neutron stars are steady X-ray emitters. Besides a few allegedly rotation-powered neutron stars that showed ‘magnetar-like’ variability, a particularly interesting case is that of PSR B0943+10. Recent observations have shown that this pulsar, well studied in the radio band where it alternates between a bright and a quiescent mode, displays significant X-ray variations, anticorrelated in flux with the radio emission. The study of such synchronous radio/X-ray mode switching opens a new window to investigate the processes responsible for the pulsar radio and high-energy emission. Here we review the main X-ray properties of PSR B0943+10 derived from recent coordinated X-ray and radio observations.

  20. Electro-optical characteristics of a chiral hybrid in-plane switching liquid crystal mode for high brightness.

    Science.gov (United States)

    Gwag, Jin Seog; Sohn, Kyunghwa; Kim, Young-Ki; Kim, Jae-Hoon

    2008-08-04

    We propose a new in-plane switching (IPS) nematic liquid crystal (LC) mode which uses a twist effect with a hybrid LC alignment and interdigitated electrodes as an approach for a high brightness. This is optimized to a normally white mode to minimize loss of transmittance at the electrode compared to the conventional IPS mode. The proposed mode shows an excellent dark state because the bulk LCs are aligned in parallel to the optic axis of the polarizer under low electric fields. Consequently, this proposed mode exhibits a much higher contrast ratio (980:1) than that of the conventional IPS mode (550:1).

  1. Improved confinement in high-density H-modes via modification of the plasma boundary with lower hybrid wavesa)

    Science.gov (United States)

    Terry, J. L.; Reinke, M. L.; Hughes, J. W.; LaBombard, B.; Theiler, C.; Wallace, G. M.; Baek, S. G.; Brunner, D.; Churchill, R. M.; Edlund, E.; Ennever, P.; Faust, I.; Golfinopoulos, T.; Greenwald, M.; Hubbard, A. E.; Irby, J.; Lin, Y.; Parker, R. R.; Rice, J. E.; Shiraiwa, S.; Walk, J. R.; Wukitch, S. J.; Xu, P.

    2015-05-01

    Injecting Lower Hybrid Range of Frequency (LHRF) waves into Alcator C-Mod's high-density H-mode plasmas has led to enhanced global energy confinement by increasing pedestal temperature and pressure gradients, decreasing the separatrix density, modifying the pedestal radial electric field and rotation, and decreasing edge turbulence. These experiments indicate that edge LHRF can be used as an actuator to increase energy confinement via modification of boundary quantities. H98-factor increases of up to ˜35% (e.g., H98 from 0.75 to 1.0) are seen when moderate amounts of LH power (PLH/Ptot ˜ 0.15) are applied to H-modes of densities n ¯ e ˜ 3 × 1020 m-3, corresponding to values ˜0.5 of the Greenwald density. However, the magnitude of the improvement is reduced if the confinement quality of the target H-mode plasma is already good (i.e., H98target ˜ 1). Ray-tracing modeling and accessibility calculations for the LH waves indicate that they do not penetrate to the core. The LHRF power appears to be deposited in plasma boundary region, with a large fraction of the injected power increment appearing promptly on the outer divertor target. There is no evidence that the LH waves are driving current in these plasmas. The LHRF-actuated improvements are well correlated with suppressed pedestal density fluctuations in the 100-300 kHz range. There is also a correlation between the improved confinement and a drop in separatrix density, a correlation that is consistent with previous H-mode results with no LHRF.

  2. Simulation of mode conversion process from upper-hybrid waves to LO-mode waves in the vicinity of the plasmapause

    Directory of Open Access Journals (Sweden)

    M. J. Kalaee

    2010-06-01

    Full Text Available In order to clarify the role of the mode conversion process in the generation mechanism of LO-mode waves in the equatorial region of the plasmasphere, we have investigated the linear mode conversion process among upper-hybrid-resonance (UHR-mode, Z-mode and LO-mode waves by a numerical simulation solving Maxwell's equations and the equation of motion of a cold electron fluid. The wave coupling process occurring in the cold magnetized plasma are examined in detail. In order to give a realistic initial plasma condition in the numerical experiments, we use initial parameters inferred from observation data obtained around the generation region of LO-mode waves obtained by the Akebono satellite. A density gradient is estimated from the observed UHR frequency, and wave normal angles are estimated from the dispersion relation of cold plasma by comparing observed wave electric fields. Then, we perform numerical experiments of mode conversion processes using the density gradient of background plasma and the wave normal angle of incident upper hybrid mode waves determined from the observation results. We found that the characteristics of reproduced LO-mode waves in each simulation run are consistent with observations.

  3. Controlled cytotoxicity of plasma treated water formulated by open-air hybrid mode discharge

    Science.gov (United States)

    Lu, P.; Boehm, D.; Cullen, P.; Bourke, P.

    2017-06-01

    Plasma treated liquids (PTLs) provide a means to convey a broad range of effects of relevance for food, environmental, or clinical decontamination, plant growth promotion, and therapeutic applications. Devising the reactive species ingredients and controlling the biological response of PTLs are of great interest. We demonstrate an approach by using an open-air hybrid mode discharge (HMD) to control the principal reactive species composition within plasma treated water (PTW), which is then demonstrated to regulate the cytotoxicity of PTW. The cytotoxicity of HMD produced PTW demonstrates a non-monotonic change over the discharge time. Although hydrogen peroxide and nitrite are not the sole effectors for cell death caused by PTW, using them as principal reactive species indicators, cytotoxicity can be removed and/or enhanced by formulating their concentrations and composition through adjusting the discharge mode and time on-line during PTW generation without the addition of additional working gas or chemical scavengers. This work demonstrates that a hybrid mode discharge can be employed to generate a PTW formulation to control a biological response such as cytotoxicity. This provides insights into how plasma treated liquids may be harnessed for biological applications in a specific and controllable manner.

  4. Far-field and near-field investigation of plasmonic-photonic hybrid laser mode

    CERN Document Server

    Zhang, Taiping; Callard, Ségolène; jamois, Cecile; Letartre, Xavier; Chevalier, Celine; Rojo-Romeo, Pedro; Devif, Brice; Viktorovitch, Pierre

    2014-01-01

    We report an approach to achieve this goal via build a plasmonic-dielectric photonic hybrid system. We induce a defect mode based photonic crystal (PC) cavity to work as a intermedium storage as well as a near-field light source to excite a plasmonic nanoantenna (NA). In this way, a plasmonic-photonic nano-laser source is created in present experiment. The coupling condition between the two elements is investigated in far-field and near-field level. We found that the NA reduces the Q-factor of the PC-cavity. Meanwhile, the NA concentrates and enhances the laser emission of the PC-cavity. This novel hybrid dielectric-plasmonic structure may open a new avenue in the generation of nano-light sources, which can be applied in areas such as optical information storage, non-linear optics, optical trapping and detection, integrated optics, etc.

  5. DE-1 and COSMOS 1809 observations of lower hybrid waves excited by VLF whistler mode waves

    Science.gov (United States)

    Bell, T. F; Inan, U. S.; Lauben, D.; Sonwalkar, V. S.; Helliwell, R. A.; Sobolev, Ya. P.; Chmyrev, V. M.; Gonzalez, S.

    1994-01-01

    Past work demostrates that strong lower hybrid (LH) waves can be excited by electromagnetic whistler mode waves throughout large regions of the topside ionosphere and magnetosphere. The effects of the excited LH waves upon the suprathermal ion population in the topside ionosphere and magnetosphere depend upon the distribution of LH wave amplitude with wavelength lambda. The present work reports plasma wave data from the DE-1 and COSMOS 1809 spacecraft which suggests that the excited LH wave spectrum has components for which lambda less than or equal to 3.5 m when excitation occurs at a frequency roughly equal to the local lower hybrid resonance frequency. This wavelength limit is a factor of approximately 3 below that reported in past work and suggests that the excited LH waves can interact with suprathermal H(+) ions with energy less than or equal to 6 eV. This finding supports recent work concerning the heating of suprathermal ions above thunderstorm cells.

  6. Comparison of three types of XPAD3.2/CdTe single chip hybrids for hard X-ray applications in material science and biomedical imaging

    Energy Technology Data Exchange (ETDEWEB)

    Buton, C., E-mail: clement.buton@synchrotron-soleil.fr [Synchrotron SOLEIL, L´Orme des Merisiers, Saint-Aubin — BP 48 91192, Gif-sur-Yvette Cedex (France); Dawiec, A. [Synchrotron SOLEIL, L´Orme des Merisiers, Saint-Aubin — BP 48 91192, Gif-sur-Yvette Cedex (France); Graber-Bolis, J.; Arnaud, K. [CPPM, Aix-Marseille Université, CNRS/IN2P3, Marseille (France); Bérar, J.F.; Blanc, N.; Boudet, N. [Université Grenoble Alpes, Institut NÉEL, F-38042 Grenoble (France); CNRS, Institut NÉEL, F-38042 Grenoble (France); Clémens, J.C.; Debarbieux, F. [CPPM, Aix-Marseille Université, CNRS/IN2P3, Marseille (France); Delpierre, P.; Dinkespiler, B. [imXPAD SAS — Espace Mistral, Athélia IV, 297 avenue du Mistral, 13600 La Ciotat (France); Gastaldi, T. [CPPM, Aix-Marseille Université, CNRS/IN2P3, Marseille (France); Hustache, S. [Synchrotron SOLEIL, L´Orme des Merisiers, Saint-Aubin — BP 48 91192, Gif-sur-Yvette Cedex (France); Morel, C.; Pangaud, P. [CPPM, Aix-Marseille Université, CNRS/IN2P3, Marseille (France); Perez-Ponce, H. [imXPAD SAS — Espace Mistral, Athélia IV, 297 avenue du Mistral, 13600 La Ciotat (France); Vigeolas, E. [CPPM, Aix-Marseille Université, CNRS/IN2P3, Marseille (France)

    2014-09-11

    The CHIPSPECT consortium aims at building a large multi-modules CdTe based photon counting detector for hard X-ray applications. For this purpose, we tested nine XPAD3.2 single chip hybrids in various configurations (i.e. Ohmic vs. Schottky contacts or electrons vs. holes collection mode) in order to select the most performing and best suited configuration for our experimental requirements. Measurements have been done using both X-ray synchrotron beams and {sup 241}Am source. Preliminary results on the image quality, calibration, stability, homogeneity and linearity of the different types of detectors are presented.

  7. Hybrid force-velocity sliding mode control of a prosthetic hand.

    Science.gov (United States)

    Engeberg, Erik D; Meek, Sanford G; Minor, Mark A

    2008-05-01

    Four different methods of hand prosthesis control are developed and examined experimentally. Open-loop control is shown to offer the least sensitivity when manipulating objects. Force feedback substantially improves upon open-loop control. However, it is shown that the inclusion of velocity and/or position feedback in a hybrid force-velocity control scheme can further improve the functionality of hand prostheses. Experimental results indicate that the sliding mode controller with force, position, and velocity feedback is less prone to unwanted force overshoot when initially grasping objects than the other controllers.

  8. The Tunable Hybrid Surface Phonon and Plasmon Polariton Modes in Boron Nitride Nanotube and Graphene Monolayer Heterostructures

    CERN Document Server

    Sun, Yu; Cheng, Jiangtao; Liu, Jiansheng

    2014-01-01

    The hybrid modes incorporating surface phonon polariton (SPhP) modes in boron nitride nanotubes (BNNTs) and surface plasmon polariton (SPP) modes in graphene monolayers are theoretically studied. The combination of the 1D BNNTs and 2D graphene monolayer further improves the modal characteristics with electrical tunability. Superior to the graphene monolayers, the proposed heterostructures supports single mode transmission with lateral optical confinement. The modal characteristics can be shifted from SPP-like toward SPhP-like. Both the figure of merit and field enhancement of hybrid modes are improved over 3 times than those of BNNT SPhP modes, which may further enable sub-wavelength mid-infrared applications.

  9. Comparison of hybrid and baseline ELMy H-mode confinement in JET with the carbon wall

    Science.gov (United States)

    Beurskens, M. N. A.; Frassinetti, L.; Challis, C.; Osborne, T.; Snyder, P. B.; Alper, B.; Angioni, C.; Bourdelle, C.; Buratti, P.; Crisanti, F.; Giovannozzi, E.; Giroud, C.; Groebner, R.; Hobirk, J.; Jenkins, I.; Joffrin, E.; Leyland, M. J.; Lomas, P.; Mantica, P.; McDonald, D.; Nunes, I.; Rimini, F.; Saarelma, S.; Voitsekhovitch, I.; de Vries, P.; Zarzoso, D.; Contributors, JET-EFDA

    2013-01-01

    The confinement in JET baseline type I ELMy H-mode plasmas is compared to that in so-called hybrid H-modes in a database study of 112 plasmas in JET with the carbon fibre composite (CFC) wall. The baseline plasmas typically have βN ˜ 1.5-2, H98 ˜ 1, whereas the hybrid plasmas have βN ˜ 2.5-3, H98 contains both low- (δ ˜ 0.2-0.25) and high-triangularity (δ ˜ 0.4) hybrid and baseline H-mode plasmas from the last JET operational campaigns in the CFC wall from the period 2008-2009. Based on a detailed confinement study of the global as well as the pedestal and core confinement, there is no evidence that the hybrid and baseline plasmas form separate confinement groups; it emerges that the transition between the two scenarios is of a gradual kind rather than demonstrating a bifurcation in the confinement. The elevated confinement enhancement factor H98 in the hybrid plasmas may possibly be explained by the density dependence in the τ98 scaling as n0.41 and the fact that the hybrid plasmas operate at low plasma density compared to the baseline ELMy H-mode plasmas. A separate regression on the confinement data in this study shows a reduction in the density dependence as n0.09±0.08. Furthermore, inclusion of the plasma toroidal rotation in the confinement regression provides a scaling with the toroidal Alfvén Mach number as Mach_A^{0.41+/- 0.07} and again a reduced density dependence as n0.15±0.08. The differences in pedestal confinement can be explained on the basis of linear MHD stability through a coupling of the total and pedestal poloidal pressure and the pedestal performance can be improved through plasma shaping as well as high β operation. This has been confirmed in a comparison with the EPED1 predictive pedestal code which shows a good agreement between the predicted and measured pedestal pressure within 20-30% for a wide range of βN ˜ 1.5-3.5. The core profiles show a strong degree of pressure profile consistency. No beneficial effect of core

  10. Hybrid nanowedge plasmonic waveguide for low loss propagation with ultra-deep-subwavelength mode confinement.

    Science.gov (United States)

    Ma, Youqiao; Farrell, Gerald; Semenova, Yuliya; Wu, Qiang

    2014-02-15

    In this Letter, a novel waveguide based on hybrid surface plasmon polaritons (HSPPs) is proposed and numerically analyzed. This waveguide consists of two dielectric nanowires placed on both sides of a nanowedge-patterned metal film, which can confine light in the ultra-deep-subwavelength region (ranging from λ²/4000 to λ²/400) with a long propagation length (ranging from 1200 to 3500 μm). Compared to a previous HSPPs waveguide without the nanowedges, with the same propagation length, our proposed structure has much higher mode confinement with 1 order of magnitude smaller normalized mode area. An investigation of the effect of structural perturbations indicates that our proposed waveguide also has good tolerance of fabrication errors. The proposed waveguide could be an interesting alternative structure to realize nanolasers and optical trapping.

  11. Degenerate four wave mixing in large mode area hybrid photonic crystal fibers

    DEFF Research Database (Denmark)

    Petersen, Sidsel Rübner; Alkeskjold, Thomas Tanggaard; Lægsgaard, Jesper

    2013-01-01

    Spontaneous degenerate four wave mixing (FWM) is investigated in large mode area hybrid photonic crystal fibers, in which photonic bandgap guidance and index guidance is combined. Calculations show the parametric gain is maximum on the edge of a photonic bandgap, for a large range of pump...... wavelengths. The FWM products are observed on the edges of a transmission band experimentally, in good agreement with the numerical results. Thereby the bandedges can be used to control the spectral positions of FWM products through a proper fiber design. The parametric gain control combined with a large mode...... area fiber design potentially allows for power scaling of light at wavelengths not easily accessible with e.g. rare earth ions....

  12. Degenerate four wave mixing in large mode area hybrid photonic crystal fibers.

    Science.gov (United States)

    Petersen, Sidsel R; Alkeskjold, Thomas T; Lægsgaard, Jesper

    2013-07-29

    Spontaneous degenerate four wave mixing (FWM) is investigated in large mode area hybrid photonic crystal fibers, in which photonic bandgap guidance and index guidance is combined. Calculations show the parametric gain is maximum on the edge of a photonic bandgap, for a large range of pump wavelengths. The FWM products are observed on the edges of a transmission band experimentally, in good agreement with the numerical results. Thereby the bandedges can be used to control the spectral positions of FWM products through a proper fiber design. The parametric gain control combined with a large mode area fiber design potentially allows for power scaling of light at wavelengths not easily accessible with e.g. rare earth ions.

  13. Hybrid paramagnon phonon modes at elevated temperatures in EuTiO3

    Science.gov (United States)

    Bussmann-Holder, A.; Guguchia, Z.; Köhler, J.; Keller, H.; Shengelaya, A.; Bishop, A. R.

    2012-09-01

    EuTiO3 (ETO) has recently experienced a significant revival of interest because of its possible multiferroic properties, which are currently the focus of much research. Unfortunately, ETO is an unlikely candidate for enlarged multifunctionality since the mode softening—typical of ferroelectrics—remains incomplete, and the antiferromagnetic properties appear only at 5.5 K. However, a strong coupling between lattice and Eu spins exists and this leads to the appearance of a magnon-phonon-hybrid mode at elevated temperatures as evidenced by EPR, muon spin relaxation experiments and model predictions based on a coupled spin-polarizability Hamiltonian. This novel finding supports the notion of strong magneto-dielectric effects being realized in ETO and opens up new strategies in material design and technological applications.

  14. Utilization of hybrid plasmonic modes to investigate surface interactions between nanocubes and polymer substrates

    Science.gov (United States)

    Bushell, Michael; Bottomley, Adam; Ianoul, Anatoli

    2017-02-01

    Silver nanocube monolayers deposited on polymer films were heated past the glass transition temperature of the polymer. Surface interactions between the cubes and substrate dictate the depth and rate of incorporation into the polymer. Silver nanocubes support hybrid plasmonic modes that are spatially separated when there is anisotropy in the local refractive index. Using this measure, it becomes possible to monitor the position of the cubes relative to the surface and tune spectral features in the visible spectrum. These spatially resolved plasmonic modes were used to probe the local glass transition temperature of polystyrene (PS), polymethylmethacrylate (PMMA) and polyvinyl chloride (PVC), the glass transition temperature of PS, PMMA, PVC were 103 ± 2, 122 ± 12, 81 ± 2 °C, respectively.

  15. Measurement of the cosmic ray energy spectrum using hybrid events of the Pierre Auger Observatory

    NARCIS (Netherlands)

    Settimo, Mariangela; Abreu, P.; Aglietta, M.; Ahlers, M.; Ahn, E.J.; Albuquerque, IFM; Allard, D.; Allekotte, I.; Allen, J.; Allison, P.; Almela, A.; Alvarez Castillo, J.; Alvarez-Muiz, J.; Alves Batista, R.; Ambrosio, M.; Aminaei, A; Anchordoqui, L.; Andring, S.; Anticic, T.; Aramo, C.; Arqueros, F.; Asorey, H.; Assis, P.; Aublin, J.; Ave, M.; Avenier, M.; Avila, G.; Badescu, A.M.; Barber, K.B.; Barbosa, A.F.; Bardenet, R.; Baughman, B.; Bauml, J.; Baus, C.; Beatty, J.J.; Becker, K.H.; Belletoile, A.; Bellido, J.A.; BenZvi, S.; Berat, C.; Bertou, X.; Biermann, P.L.; Billoir, P.; Blanco, F.; Blanco, M.; Bleve, C.; Blumer, H.; Bohacova, M.; Boncioli, D.; Bonifazi, C.; Bonino, R.; Boroda, N.; Brack, J.; Brancus, I.; Brogueira, P.; Brown, W.C.; Bruijn, R.; Buchholz, P.; Bueno, A.; Buroker, L.; Burton, R.E.; Cabellero-Mora, K.S.; Caccianiga, B.; Caramete, L.; Caruso, R.; Castellina, A.; Catalano, O.; Cataldi, G.; Cazon, L.; Cester, R.; Chauvin, J.; Cheng, S.H.; Chiavassa, A.; Chinellato, J.A.; Chirinos Diaz, J.; Chudoba, J.; Cilmo, M.; Clay, R.W.; Cocciolo, G.; Collica, L.; Coluccia, M.R.; Conceicao, R.; Contreras, F.; Cook, H.; Cooper, M.J.; Coppens, J.; Cordier, A.; Coutu, S.; Covault, C.E.; Creusot, A.; Criss, A.; Cronin, J.; Curutiu, A.; Dagoret-Campagne, S.; Dallier, R.; Daniel, B.; Dasso, S.; Daumiller, K.; Dawson, B.R.; de Almeida, R.M.; De Domenico, M.; De Donato, C.; de Jong, S.J.; De La Vega, G.; de Mello Junior, W.J.M.; de Mello Neto, J.R.T.; De Mitri, I.; de Souza, V.; de Vries, K.D.; del Peral, L.; del Rio, M.; Deligny, O.; Dembinski, H.; Dhital, N.; Di Giulio, C.; Diaz Castro, M.L.; Diep, P.N.; Diogo, F.; Dobrigkeit, C.; Docters, W.; D'Olivo, J.C.; Dong, PN; Dorofeev, A.; dos Anjos, JC; Dova, M.T.; D'Urso, D.; Dutan, I.; Ebr, J.; Engel, R.; Erdmann, M.; Escobar, C.O.; Espadanal, J.; Etchegoyen, A.; Facal San Luis, P.; Falcke, H.; Fang, K.; Farrar, G.; Fauth, A.C.; Fazzini, N.; Ferguson, A.P.; Fick, B.; Figueira, J.M.; Filevich, A.; Filevich, A.; Fliescher, S.; Fracchiolla, C.E.; Fraenkel, E.D.; Fratu, O.; Frohlich, U.; Fuchs, B.; Gaior, R.; Gamarra, R.F.; Gambetta, S.; Garcia, B.; Garcia Roca, S.T.; Garcia-Gamez, D.; Garcia-Pinto, D.; Garilli, G.; Gascon Bravo, A.; Gemmeke, H.; Ghia, P.L.; Giller, M.; Gitto, J.; Glass, H.; Gold, M.S.; Golup, G.; Gomez Albarracin, F.; Gomez Berisso, M.; Gomez Vitale, P.F.; Goncalves, P.; Gonzalez, J.G.; Gookin, B.; Gorgi, A.; Gouffon, P.; Grashorn, E.; Grebe, S.; Griffith, N.; Grillo, A.F.; Guardincerri, Y.; Guarino, F.; Guedes, G.P.; Hansen, P.; Harari, D.; Harrison, T.A.; Harton, J.L.; Haungs, A.; Hebbeker, T.; Heck, D.; Herve, A.E.; Hill, G.C.; Hojvat, C.; Hollon, N.; Holmes, V.C.; Homola, P.; Horandel, J.R.; Horvath, P.; Hrabovsky, M.; Huber, D.; Huege, T.; Insolia, A.; Ionita, F.; Italiano, A.; Jansen, S.; Jarne, C.; Jiraskova, S.; Josebachuili, M.; Kadija, K.; Kampert, K.H.; Karhan, P.; Kasper, P.; Katkov, I.; Kegl, B.; Keilhauer, B.; Keivani, A.; Kelley, J.L.; Kemp, E.; Kieckhafer, R.M.; Klages, H.O.; Kleifges, M.; Kleinfeller, J.; Knapp, J.; Koang, D.H.; Kotera, K.; Krohm, N.; Kromer, O.; Kruppke-Hansen, D.; Kuempel, D.; Kulbartz, J.K.; Kunka, N.; La Rosa, G.; Lachaud, C.; LaHurd, D.; Latronico, L.; Lauer, R.; Lautridou, P.; Le Coz, S.; Leao, M.S.A.B.; Lebrun, D.; Lebrun, P.; Leigui de Oliveira, M.A.; Letessier-Selvon, A.; Lhenry-Yvon, I.; Link, K.; Lopez, R.; Lopez Aguera, A.; Louedec, K.; Lozano Bahilo, J.; Lu, L.; Lucero, A.; Ludwig, M.; Lyberis, H.; Maccarone, M.C.; Macolino, C.; Maldera, S.; Maller, J.; Mandat, D.; Mantsch, P.; Mariazzi, A.G.; Marin, J.; Marin, V.; Maris, I.C.; Marquez Falcon, H.R.; Marsella, G.; Martello, D.; Martinez, H.; Martinez Bravo, O.; Martraire, D.; Masias Meza, [No Value; Mathes, H.J.; Matthews, J.; Matthews, J.A.J.; Matthiae, G.; Maurel, D.; Maurizio, D.; Mazur, P.O.; Medina-Tanco, G.; Melissas, M.; Melo, D.; Menichetti, E.; Menshikov, A.; Mertsch, P.; Messina, S.; Meurer, C.; Meyhandan, R.; Mi'canovi'c, S.; Micheletti, M.I.; Minaya, I.A.; Miramonti, L.; Molina-Bueno, L.; Mollerach, S.; Monasor, M.; Monnier Ragaigne, D.; Montanet, F.; Morales, B.; Morello, C.; Moreno, J.C.; Mostafa, M.; Moura, C.A.; Muller, M.A.; Muller, G.; Munchmeyer, M.; Mussa, R.; Navarra, G.; Navarro, J.L.; Navas, S.; Necesal, P.; Nellen, L.; Nelles, A.; Neuser, J.; Nhung, P.T.; Niechciol, M.; Niemietz, L.; Nierstenhoefer, N.; Nitz, D.; Nosek, D.; Nozka, L.; Oehlschlager, J.; Olinto, A.; Ortiz, M.; Pacheco, N.; Pakk Selmi-Dei, D.; Palatka, M.; Pallotta, J.; Palmieri, N.; Parente, G.; Parizot, E.; Parra, A.; Pastor, S.; Paul, T.; Pech, M.; Pekala, J.; Pelayo, R.; Pepe, I.M.; Perrone, L.; Pesce, R.; Petermann, E.; Petrera, S.; Petrolini, A.; Petrov, Y.; Pfendner, C.; Piegaia, R.; Pierog, T.; Pieroni, P.; Pimenta, M.; Pirronello, V.; Platino, M.; Plum, M.; Revenu, B.; Ridky, J.; Riggi, S.; Risse, M.; Ristori, P.; Rivera, H.; Rizi, V.; Roberts, J.; Rodrigues de Carvalho, W.; Rodriguez, G.; Rouille-d'Orfeuil, B.; Roulet, E.; Rovero, A.C.; Ruhle, C.; Saftoiu, A.; Salamida, F.; Salazar, H.; Salesa Greus, F.; Salina, G.; Sanchez, F.; Santo, C.E.; Santos, E.; Santos, E.M.; Sarazin, F.; Sarkar, B.; Sarkar, S.; Sato, R.; Scharf, N.; Scherini, V.; Schieler, H.; Schiffer, P.; Schmidt, A.; Scholten, O.; Schoorlemmer, H.; Schovancova, J.; Schovanek, P.; Schroder, F.; Schuster, D.; Sciutto, S.J.; Scuderi, M.; Segreto, A.; Settimo, M.; Shadkam, A.; Shellard, R.C.; Sidelnik, I.; Sigl, G.; Silva Lopez, H.H.; Sima, O.; Smialkowski, A.; Smida, R.; Snow, G.R.; Sommers, P.; Sorokin, J.; Spinka, H.; Squartini, R.; Srivastava, Y.N.; Stanic, S.; Stapleton, J.; Stasielak, J.; Stephan, M.; Stutz, A.; Suarez, F.; Suomijarvi, T.; Supanitsky, A.D.; Susa, T.; Sutherland, M.S.; Swain, J.; Szadkowski, Z.; Szuba, M.; Tapia, A.; Tartare, M.; Tascau, O.; Tcaciuc, R.; Thao, N.T.; Thomas, D.; Tiffenberg, J.; Timmermans, C.; Tkaczyk, W.; Todero Peixoto, C.J.; Toma, G.; Tomankova, L.; Tome, B.; Tonachini, A.; Torralba Elipe, G.; Travnicek, P.; Tridapalli, D.B.; Tristram, G.; Trovato, E.; Tueros, M.; Ulrich, R.; Unger, M.; Urban, M.; Valdes Galicia, J.F.; Valino, I.; Valore, L.; van Aar, G.; van den Berg, A.M.; van Velzen, S.; van Vliet, A.; Varela, E.; Vargas Cardenas, B.; Vazquez, JR; Vazquez, R.A.; Veberic, D.; Verzi, V.; Vicha, J.; Videla, M.; Villasenor, L.; Wahlberg, H.; Wahrlich, P.; Wainberg, O.; Walz, D.; Watson, A.A.; Weber, M.; Weidenhaupt, K.; Weindl, A.; Werner, F.; Westerhoff, S.; Whelan, B.J.; Widom, A.; Wieczorek, G.; Wiencke, L.; Wilczynska, B.; Wilczynski, H.; Will, M.; Williams, C.; Winchen, T.; Wommer, M.; Wundheiler, B.; Yamamoto, T.; Yapici, T.; Younk, P.; Yuan, G.; Yushkov, A.; Zamorano Garcia, B.; Zas, E.; Zavrtanik, D.; Zavrtanik, M.; Zaw, I.; Zepeda, A.; Zhou, J.; Zhu, Y.; Zimbres Silva, M.; Ziolkowski, M.; Martin, L.

    2012-01-01

    The energy spectrum of ultra-high energy cosmic rays above 10(18)eV is measured using the hybrid events collected by the Pierre Auger Observatory between November 2005 and September 2010. The large exposure of the Observatory allows the measurement of the main features of the energy spectrum with hi

  16. Self-referenced refractive index sensing with hybrid-Tamm-plasmon-polariton modes in sub-wavelength analyte layers

    Science.gov (United States)

    Kumar, Samir; Shukla, Mukesh Kumar; Sona Maji, Partha; Das, Ritwick

    2017-09-01

    A coupled Tamm-plasmon-polariton (TPP) hybrid-mode based self-referenced refractive-index sensor is proposed. The geometry is comprised of a sub-wavelength analyte (sensing) layer sandwiched between two metal-clad distributed-Bragg-reflectors (DBRs). Reflection spectrum of the geometry exhibits two discernible reflectivity minima within the photonic-bandgap of DBR. The reflectivity minima are essentially due to excitation of two hybrid modes which have symmetric and anti-symmetric field distribution about the center resulting in an anti-crossing behaviour exhibited by hybrid-TPP mode dispersion curves. The low frequency symmetric mode exhibits strong dispersive properties by virtue of significant presence of mode-field in sensing medium. On the other hand, the high-frequency anti-symmetric mode remains unchanged with alterations in sensing layer. Thus, we propose a self-referenced sensing scheme using hybrid-TPP modes with sensitivity varying from 65~nm~RIU-1 to 180~nm~RIU-1 in the visible band. In addition, the TPP resonance are appreciably sharp as compared to surface-plasmon based geometries which results in improved detection accuracy and figure of merit. We also present an analysis for optimizing the sensor design for enhancing the sensitivity as well as detection accuracy.

  17. Model predictive control of an air suspension system with damping multi-mode switching damper based on hybrid model

    Science.gov (United States)

    Sun, Xiaoqiang; Yuan, Chaochun; Cai, Yingfeng; Wang, Shaohua; Chen, Long

    2017-09-01

    This paper presents the hybrid modeling and the model predictive control of an air suspension system with damping multi-mode switching damper. Unlike traditional damper with continuously adjustable damping, in this study, a new damper with four discrete damping modes is applied to vehicle semi-active air suspension. The new damper can achieve different damping modes by just controlling the on-off statuses of two solenoid valves, which makes its damping adjustment more efficient and more reliable. However, since the damping mode switching induces different modes of operation, the air suspension system with the new damper poses challenging hybrid control problem. To model both the continuous/discrete dynamics and the switching between different damping modes, the framework of mixed logical dynamical (MLD) systems is used to establish the system hybrid model. Based on the resulting hybrid dynamical model, the system control problem is recast as a model predictive control (MPC) problem, which allows us to optimize the switching sequences of the damping modes by taking into account the suspension performance requirements. Numerical simulations results demonstrate the efficacy of the proposed control method finally.

  18. X-ray bounds on the r-mode amplitude in millisecond pulsars

    CERN Document Server

    Schwenzer, Kai; Güver, Tolga; Vurgun, Eda

    2016-01-01

    r-mode astroseismology provides a unique way to study the internal composition of compact stars. Due to their precise timing, recycled millisecond radio pulsars present a particularly promising class of sources. Although their thermal properties are still poorly constrained, X-ray data is very useful for astroseismology since r-modes could strongly heat a star. Using known and new upper bounds on the temperatures and luminosities of several non-accreting millisecond radio pulsars we derive bounds on the r-mode amplitude as low as $\\alpha\\lesssim10^{-8}$ and discuss the impact on scenarios for their internal composition.

  19. Mode conversion and electron heating near the upper hybrid resonance frequency

    Energy Technology Data Exchange (ETDEWEB)

    Smith, B.L.; Okuda, H.; Abe, H.

    1983-11-01

    Mode conversion near the upper hybrid resonance frequency and electron heating are studied using a one-dimensional electromagnetic relativistic particle code. It is found that for a sufficiently small pump field E/sub 0/, E/sub 0//sup 2//4..pi..nT/sub e/ less than or equal to 0.01, electron heating is localized in a region near the electron cyclotron layer where the pump frequency is equal to the local electron gyrofrequency. For stronger pump fields, electron heating takes place more or less uniformly across a region between the upper hybrid resonance layer and the cyclotron layer. In addition, a significant fraction of electromagnetic energy associated with the pump is found to be reflected back into the vacuum from a region in the plasma near the upper hybrid resonance layer for both strong (E/sub 0//sup 2//4..pi..nT/sub e/ approx. = 1) and weak pumps (E/sub 0//sup 2//4..pi..nT/sub e/ << 1).

  20. Coordination Control Strategy for AC/DC Hybrid Microgrids in Stand-Alone Mode

    Directory of Open Access Journals (Sweden)

    Dwi Riana Aryani

    2016-06-01

    Full Text Available Interest in DC microgrids is rapidly increasing along with the improvement of DC power technology because of its advantages. To support the integration process of DC microgrids with the existing AC utility grids, the form of hybrid AC/DC microgrids is considered for higher power conversion efficiency, lower component cost and better power quality. In the system, AC and DC portions are connected through interlink bidirectional AC/DC converters (IC with a proper control system and power management. In the stand-alone operation mode of AC/DC hybrid microgrids, the control of power injection through the IC is crucial in order to maintain the system security. This paper mainly deals with a coordination control strategy of IC and a battery energy storage system (BESS converter under stand-alone operation. A coordinated control strategy for the IC, which considers the state of charge (SOC level of BESS and the load shedding scheme as the last resort, is proposed to obtain better power sharing between AC and DC subgrids. The scheme will be tested with a hybrid AC/DC microgrid, using the tool of the PSCAD/EMTDC software.

  1. Trapping mid-infrared rays in a lossy film with the Berreman mode, epsilon near zero mode, and magnetic polaritons.

    Science.gov (United States)

    Chen, Yu-Bin; Chiu, Feng-Cheng

    2013-09-09

    Triple mechanisms were employed to trap mid-infrared (mid-IR) rays within a semi-transparent SiO(2) film sandwiched between gold gratings and a gold substrate. Dimensions of four absorbers were explicitly determined using an LC (inductor-capacitor) circuit model considering the role transition of SiO(2) film. The film behaves as a capacitance and an inductance when the real part of relative electric permittivity for SiO(2) is positive and negative, respectively. At the normal incidence of transverse magnetic waves, every absorptance spectrum of absorbers showed a peak at wavelength λ = 10 μm due to the first mode excitation of magnetic polaritons (MP). At oblique incidence, the Berreman mode led to another peak at λ = 8 μm while its bandwidth was expanded with epsilon near zero mode excited by diffracted waves. The full-width-at-half-maximum of both peaks exceeded 0.6 μm thanks to the SiO(2) loss. Other minor absorptance peaks in the mid-IR were caused by variants of the same MP mode.

  2. A Control Strategy for Mode Transition with Gear Shifting in a Plug-In Hybrid Electric Vehicle

    Directory of Open Access Journals (Sweden)

    Kyuhyun Sim

    2017-07-01

    Full Text Available The mode transition from electric propulsion mode to hybrid propulsion mode is important with regard to the power management strategy of plug-in hybrid electric vehicles (PHEVs. This is because mode transitions can occur frequently depending on the power management strategies and driving cycles, and because inadequate mode transitions worsen the fuel efficiency and drivability. A pre-transmission parallel PHEV uses a clutch between the internal combustion engine (ICE and the electric motor (EM to connect or disconnect the power source of the ICE for a mode transition. The mode transition requires additional energy consumption for clutch speed synchronization, and is accompanied by a drivetrain shock due to clutch engagement. This paper proposes a control strategy for the mode transition with gear-shifting to resolve the problems of energy consumption and drivetrain shock. Through the development of a PHEV performance simulator, we analyze the mode transition characteristics and propose a control strategy considering the vehicle acceleration and gear state. The control strategy reduces the duration required for the mode transition by moving the start time of the mode transition. This helps to improve energy efficiency while maintaining adequate drivability.

  3. Pixel readout ASIC for an APD based 2D X-ray hybrid pixel detector with sub-nanosecond resolution

    Energy Technology Data Exchange (ETDEWEB)

    Thil, Ch., E-mail: christophe.thil@ziti.uni-heidelberg.d [Heidelberg University, Institute of Computer Engineering, B6, 26, 68161 Mannheim (Germany); Baron, A.Q.R. [RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5148 (Japan); Fajardo, P. [ESRF, Polygone Scientifique Louis Neel, 6, rue Jules Horowitz, 38000 Grenoble (France); Fischer, P. [Heidelberg University, Institute of Computer Engineering, B6, 26, 68161 Mannheim (Germany); Graafsma, H. [DESY, Notkestrasse 85, 22607 Hamburg (Germany); Rueffer, R. [ESRF, Polygone Scientifique Louis Neel, 6, rue Jules Horowitz, 38000 Grenoble (France)

    2011-02-01

    The fast response and the short recovery time of avalanche photodiodes (APDs) in linear mode make those devices ideal for direct X-ray detection in applications requiring high time resolution or counting rate. In order to provide position sensitivity, the XNAP project aims at creating a hybrid pixel detector with nanosecond time resolution based on a monolithic APD sensor array with 32 x32 pixels covering about 1 cm{sup 2} active area. The readout is implemented in a pixelated front-end ASIC suited for the readout of such arrays, matched to pixels of 280{mu}mx280{mu}m size. Every single channel features a fast transimpedance amplifier, a discriminator with locally adjustable threshold and two counters with high dynamic range and counting speed able to accumulate X-ray hits with no readout dead time. Additionally, the detector can be operated in list mode by time-stamping every single event with sub-nanosecond resolution. In a first phase of the project, a 4x4 pixel test module is built to validate the conceptual design of the detector. The XNAP project is briefly presented and the performance of the readout ASIC is discussed.

  4. Revealing the physics of r modes in low-mass X-ray binaries

    NARCIS (Netherlands)

    Ho, W.C.G.; Andersson, N.; Haskell, B.

    2011-01-01

    We consider the astrophysical constraints on the gravitational-wave-driven r-mode instability in accreting neutron stars in low-mass x-ray binaries. We use recent results on superfluid and superconducting properties to infer the core temperature in these neutron stars and show the diversity of the o

  5. Synchronous X-ray and radio mode switches: a rapid global transformation of the pulsar magnetosphere

    NARCIS (Netherlands)

    Hermsen, W.; Hessels, J.W.; Kuiper, L.; Leeuwen, van J.; Mitra, D.; Plaa, de J.; Rankin, J.M.; Stappers, B.W.; Wright, G.A.E.; Basu, R.; Alexov, A.; Coenen, T.; Griessmeier, J.M.; Hassall, T.E.; Karastergiou, A.; Keane, E.; Kondratiev, V.I.; Kramer, M.; Kuniyoshi, M.; Noutsos, A.; Serylak, M.; Pilia, M.; Sobey, C.; Weltevrede, P.; Zagkouris, K.; Asgekar, A.; Avruch, I.M.; Batejat, F.; Bell, M.E.; Bell, M.R.; Bentum, M.J.; Bernardi, G.; Best, P.; Birzan, L.; Bonfede, A.; Breitling, F.; Broderick, J.; Brüggen, M.; Butcher, H.R.; Ciardi, B.; Duscha, S.; Eislöffel, J.; Falcke, H.; Fender, R.; Ferrari, C.; Frieswijk, W.; Garrett, M.A.; Gasperin, de F.; Geus, de E.; Gunst, A.W.; Heald, G.; Hoeft, M.; Homeffer, A.; Iabobelli, M.; Kuper, G.; Maat, P.; Macario, G.; Markoff, S.; McKean, J.P.; Mevius, M.; Miller-Jones, J.C.A.; Morganti, R.; Munk, H.; Orrú, E.; Paas, H.; Pandey-Pommier, M.; Pandey, V.N.; Pizzo, R.; Polatidis, A.G.; Rawlings, S.; Reich, W.; Röttgering, H.; Scaife, A.M.M.; Schoenmakers, A.; Shulevski, A.; Sluman, J.; Steinmetz, M.; Tagger, M.; Tang, Y.; Tasse, C.; Veen, ter S.; Vermeulen, R.; Brink, van de R.H.; Weeren, van R.J.; Weijers, R.A.M.J.; Wise, M.W.; Wucknitz, O.; Yatawatta, S.; Zarka, P.

    2013-01-01

    Pulsars emit from low-frequency radio waves up to high-energy gamma-rays, generated anywhere from the stellar surface out to the edge of the magnetosphere. Detecting correlated mode changes across the electromagnetic spectrum is therefore key to understanding the physical relationship among the emis

  6. Nonradial g-mode oscillations in X-ray bursting neutron stars

    Science.gov (United States)

    Mcdermott, P. N.; Taam, Ronald E.

    1987-01-01

    The oscillation spectrum of nonradial g-modes in X-ray bursting neutron stars has been studied. The pulsation periods are found to be sensitive to the envelope temperature and range from about 15 ms to about 50 ms for the l = 1 g(1) mode during the X-ray burst. From a quasi-adiabatic stability analysis it is likely that a spectrum of l-pole g-modes is unstable due to the epsilon-mechanism associated with rapid alpha captures. As the thermal structure of the envelope of the neutron star changes on time scales less than 0.2 s during the rise of the X-ray burst, the oscillations are expected to be quasi-coherent during this phase. The calculated period derivatives are large during the burst and are about 1 ms/s. The pulsations are short-lived and are most likely to be seen in the immediate vicinity of the burst peak. Finally, the possible relevance of nonradial g-mode pulsations to the recently discovered quasi-periodic oscillations observed in a number of X-ray sources is discussed.

  7. Hybrid object detection system for x-ray radiographs

    Science.gov (United States)

    Vita, Joshua A.; Wantuch, Andrew C.; Jimenez, Edward S.; Bray, Iliana E.

    2016-10-01

    While object detection is a relatively well-developed field with respect to visible light photographs, there are significantly fewer algorithms designed to work with other imaging modalities. X-ray radiographs have many unique characteristics that introduce additional challenges that can cause common image processing and object detection algorithms to begin to fail. Examples of these problematic attributes include the fact that radiographs are only represented in gray scale with similar textures and that transmission overlap occurs when multiple objects are overlaid on top of each other. In this paper we not only analyze the effectiveness of common object detection techniques as applied to our specific database, but also outline how we combined various techniques to improve overall performance. While significant strides have been made towards developing a robust object detection algorithm for use with the given database, it is still a work in progress. Further research will be needed in order to deal with the specific obstacles posed by radiographs and X-ray imaging systems. Success in this project would have disruptive repercussions in fields ranging from medical imaging to manufacturing quality assurance and national security.

  8. Oblique Bernstein Mode Generation Near the Upper-hybrid Frequency in Solar Pre-flare Plasmas

    Science.gov (United States)

    Kryshtal, A.; Fedun, V.; Gerasimenko, S.; Voitsekhovska, A.

    2015-11-01

    We study analytically the generation process of the first harmonics of the pure electron weakly oblique Bernstein modes. This mode can appear as a result of the rise and development of a corresponding instability in a solar active region. We assume that this wave mode is modified by the influence of pair Coulomb collisions and a weak large-scale sub-Dreicer electric field in the pre-flare chromosphere near the footpoints of a flare loop. To describe the pre-flare plasma we used the model of the solar atmosphere developed by Fontenla, Avrett, and Loeser ( Astrophys. J. 406, 319, 1993). We show that the generated first harmonic is close to the upper-hybrid frequency. This generation process begins at the very low threshold values of the sub-Dreicer electric field and well before the beginning of the preheating phase of a flare. We investigate the necessary conditions for the existence of non-damped first harmonics of oblique Bernstein waves with small amplitudes in the flare area.

  9. Failure mode and effects analysis using intuitionistic fuzzy hybrid weighted Euclidean distance operator

    Science.gov (United States)

    Liu, Hu-Chen; Liu, Long; Li, Ping

    2014-10-01

    Failure mode and effects analysis (FMEA) has shown its effectiveness in examining potential failures in products, process, designs or services and has been extensively used for safety and reliability analysis in a wide range of industries. However, its approach to prioritise failure modes through a crisp risk priority number (RPN) has been criticised as having several shortcomings. The aim of this paper is to develop an efficient and comprehensive risk assessment methodology using intuitionistic fuzzy hybrid weighted Euclidean distance (IFHWED) operator to overcome the limitations and improve the effectiveness of the traditional FMEA. The diversified and uncertain assessments given by FMEA team members are treated as linguistic terms expressed in intuitionistic fuzzy numbers (IFNs). Intuitionistic fuzzy weighted averaging (IFWA) operator is used to aggregate the FMEA team members' individual assessments into a group assessment. IFHWED operator is applied thereafter to the prioritisation and selection of failure modes. Particularly, both subjective and objective weights of risk factors are considered during the risk evaluation process. A numerical example for risk assessment is given to illustrate the proposed method finally.

  10. Dependency of Tearing Mode Stability on Current and Pressure Profiles in DIII-D Hybrid Discharges

    Science.gov (United States)

    Kim, K.; Park, J. M.; Murakami, M.; La Haye, R. J.; Na, Y.-S.; SNU/ORAU; ORNL; Atomics, General; SNU; DIII-D Team

    2016-10-01

    Understanding the physics of the onset and evolution of tearing modes (TMs) in tokamak plasmas is important for high- β steady-state operation. Based on DIII-D steady-state hybrid experiments with accurate equilibrium reconstruction and well-measured plasma profiles, the 2/1 tearing mode can be more stable with increasing local current and pressure gradient at rational surface and with lower pressure peaking and plasma inductance. The tearing stability index Δ', estimated by the Rutherford equation with experimental mode growth rate was validated against Δ' calculated by linear eigenvalue solver (PEST3); preliminary comprehensive MHD modeling by NIMROD reproduced the TM onset reasonably well. We present a novel integrated modeling for the purpose of predicting TM onset in experiment by combining a model equilibrium reconstruction using IPS/FASTRAN, linear stability Δ' calculation using PEST3, and fitting formula for critical Δ' from NIMROD. Work supported in part by the US DoE under DE-AC05-06OR23100, DE-AC05-00OR22725, and DEFC02-04ER54698.

  11. Direct X-ray detection with hybrid solar cells based on organolead halide perovskites

    Science.gov (United States)

    Gill, Hardeep Singh; Elshahat, Bassem; Sajo, Erno; Kumar, Jayant; Kokil, Akshay; Zygmanski, Piotr; Li, Lian; Mosurkal, Ravi

    2014-03-01

    Organolead halide perovskite materials are attracting considerable interest due to their exceptional opto-electronic properties, such as, high charge carrier mobilities, high exciton diffusion length, high extinction coefficients and broad-band absorption. These interesting properties have enabled their application in high performance hybrid photovoltaic devices. The high Z value of their constituents also makes these materials efficient for absorbing X-rays. Here we will present on the efficient use of hybrid solar cells based on organolead perovskite materials as X-ray detectors. Hybrid solar cells based on CH3NH3PbI3 were fabricated using facile processing techniques on patterned indium tin oxide coated glass substrates. The solar cells typically had a planar configuration of ITO/CH3NH3PbI3/P3HT/Ag. High sensitivity for X-rays due to high Z value, larger carrier mobility and better charge collection was observed. Detecting X-rays with energies relevant to medical oncology applications opens up the potential for diagnostic imaging applications.

  12. A Three-Dimensional Ray Tracing Study on Whistler-Mode Chorus During Geomagnetic Activities%A Three-Dimensional Ray Tracing Study on Whistler-Mode Chorus During Geomagnetic Activities

    Institute of Scientific and Technical Information of China (English)

    周庆华; 史建魁; 肖伏良

    2011-01-01

    A three-dimensional ray tracing study of a whistler-mode chorus is conducted for different geomagnetic activities by using a global core plasma density model. For the upperband chorus, the initial azimuthal wave angle affects slightly the projection of ray trajectories onto the plane (Z, √(x^2 + y^2)), but controls the longitudinal propagation. The trajectory of the upper-band chorus is strongly associated with the plasmapause and the magnetic local time (MLT) of chorus source region. For the high geomagnetic activity, the chorus trajectory moves inward together with the plasmapause. In the bulge region, the plasmapause extends outward, while the chorus trajectory moves outward together with the plasmapause. For moderately or high geomagnetic activity, the lower-band chorus suffers low hybrid resonance (LHR) reflection before it reaches the plasmapause, leading to a weak correlation with the geomagnetic activity and magnetic local time of the chorus source region. For low geomagnetic activity, the lower-band chorus may be reflected firstly at the plasmapause instead of suffering LHR reflection, exhibiting a propagation characteristic similar to that of the upper-band chorus. The results provide a new insight into the propagation characteristics of the chorus for different geomagnetic activities and contribute to further understanding of the acceleration of energetic electron by a chorus wave.

  13. The Energy Dependence of Neutron Star Surface Modes and X-ray Burst Oscillations

    CERN Document Server

    Piro, A L; Piro, Anthony L.; Bildsten, Lars

    2006-01-01

    We calculate the photon energy dependence of the pulsed amplitude of neutron star (NS) surface modes. Simple approximations demonstrate that it depends most strongly on the bursting NS surface temperature. This result compares well with full integrations that include Doppler shifts from rotation and general relativistic corrections to photon propagation. We show that the energy dependence of type I X-ray burst oscillations agrees with that of a surface mode, lending further support to the hypothesis that they originate from surface waves. The energy dependence of the pulsed emission is rather insensitive to the NS inclination, mass and radius, or type of mode, thus hindering constraints on these parameters. We also show that, for this energy-amplitude relation, the majority of the signal (relative to the noise) comes in the 2-25 keV band, so that the current burst oscillation searches with the Rossi X-Ray Timing Explorer are close to optimal. The critical test of the mode hypothesis for X-ray burst oscillatio...

  14. Asymptotic theory of gravity modes in rotating stars. I. Ray dynamics

    Science.gov (United States)

    Prat, V.; Lignières, F.; Ballot, J.

    2016-03-01

    Context. The seismology of early-type stars is limited by our incomplete understanding of gravito-inertial modes. Aims: We develop a short-wavelength asymptotic analysis for gravito-inertial modes in rotating stars. Methods: The Wentzel-Kramers-Brillouin approximation was applied to the equations governing adiabatic small perturbations about a model of a uniformly rotating barotropic star. Results: A general eikonal equation, including the effect of the centrifugal deformation, is derived. The dynamics of axisymmetric gravito-inertial rays is solved numerically for polytropic stellar models of increasing rotation and analysed by describing the structure of the phase space. Three different types of phase-space structures are distinguished. The first type results from the continuous evolution of structures of the non-rotating integrable phase space. It is predominant in the low-frequency region of the phase space. The second type of structures are island chains associated with stable periodic rays. The third type of structures are large chaotic regions that can be related to the envelope minimum of the Brunt-Väisälä frequency. Conclusions: Gravito-inertial modes are expected to follow this classification, in which the frequency spectrum is a superposition of sub-spectra associated with these different types of phase-space structures. The detailed confrontation between the predictions of this ray-based asymptotic theory and numerically computed modes will be presented in a companion paper.

  15. Anticrossing double Fano resonances generated in metallic/dielectric hybrid nanostructures using nonradiative anapole modes for enhanced nonlinear optical effects.

    Science.gov (United States)

    Zhai, Wu-Chao; Qiao, Tie-Zhu; Cai, Dong-Jin; Wang, Wen-Jie; Chen, Jing-Dong; Chen, Zhi-Hui; Liu, Shao-Ding

    2016-11-28

    Third-harmonic generation with metallic or dielectric nanoparticles often suffer from, respectively, small modal volumes and weak near-field enhancements. This study propose and demonstrate that a metallic/dielectric hybrid nanostructure composed of a silver double rectangular nanoring and a silicon square nanoplate can be used to overcome these obstacles for enhanced third-harmonic generation. It is shown that the nonradiative anapole mode of the Si plate can be used as a localized source to excite the dark subradiant octupole mode of the Ag ring, and the mode hybridization leads to the formation of an antibonding and a bonding subradiant collective mode, thereby forming anticrossing double Fano resonances. With the strong coupling between individual particles and the effectively suppressed radiative losses of the Fano resonances, several strong hot spots are generated around the Ag ring due to the excitation of the octupole mode, and electromagnetic fields within the Si plate are also strongly amplified, making it possible to confine more incident energy inside the dielectric nanoparticle. Calculation results reveal that the confined energy inside the Si plate and the Ag ring for the hybrid structures can be about, respectively, more than three times and four orders stronger than that of the corresponding isolated nanoparticles, which makes the designed hybrid nanostructure a promising platform for enhanced third-harmonic generation.

  16. Bearing fault detection based on hybrid ensemble detector and empirical mode decomposition

    Science.gov (United States)

    Georgoulas, George; Loutas, Theodore; Stylios, Chrysostomos D.; Kostopoulos, Vassilis

    2013-12-01

    Aiming at more efficient fault diagnosis, this research work presents an integrated anomaly detection approach for seeded bearing faults. Vibration signals from normal bearings and bearings with three different fault locations, as well as different fault sizes and loading conditions are examined. The Empirical Mode Decomposition and the Hilbert Huang transform are employed for the extraction of a compact feature set. Then, a hybrid ensemble detector is trained using data coming only from the normal bearings and it is successfully applied for the detection of any deviation from the normal condition. The results prove the potential use of the proposed scheme as a first stage of an alarm signalling system for the detection of bearing faults irrespective of their loading condition.

  17. Hybrid Quantum System of a Nanofiber Mode Coupled to Two Chains of Optically Trapped Atoms

    CERN Document Server

    Zoubi, Hashem

    2010-01-01

    A tapered optical nanofiber simultaneously used to trap and optically interface of cold atoms through evanescent fields constitutes a new and well controllable hybrid quantum system. The atoms are trapped in two parallel 1D optical lattices generated by suitable far blue and red detuned evanescent field modes very close to opposite sides of the nanofiber surface. Collective electronic excitations (excitons) of each of the optical lattices are resonantly coupled to the second lattice forming symmetric and antisymmetric common excitons. In contrast to the inverse cube dependence of the individual atomic dipole-dipole interaction, we analytically find an exponentially decaying coupling strength with distance between the lattices. The resulting symmetric (bright) excitons strongly interact with the resonant nanofiber photons to form fiber polaritons, which can be observed through linear optical spectra. For large enough wave vectors the polariton decay rate to free space is strongly reduced, which should render t...

  18. An ultra-narrow-band optical filter based on whispering-gallery-mode hybrid-microsphere-cavity

    Science.gov (United States)

    Wan, Hongdan; Zhu, Haohan; Liu, Linqian; Xu, Ji; Wang, Jin

    2016-10-01

    We demonstrate an ultra-narrow-band mode-selection method based on a hybrid-microsphere-cavity which consists of a coated silica microsphere. Optical field distribution and narrow-band transmission spectrum of the whispering gallery modes (WGM) are investigated by finite-difference time-domain method. WGM transmission spectra are measured for microsphere and tapered fibers with different diameters. A high refractive index layer coated on the microsphere-cavity make the Q factor increased, the transmission spectrum bandwidth compressed and the side-mode suppression ratio increased. Parameters of the hybrid-microsphere-cavity, namely, the coated shell thickness and its refractive index are optimized under different excitation light source as to investigate the whispering-gallery-modes' transmission spectrum. The 3dB bandwidth of the proposed filter can be less than MHz which will have great potential for applications in all-optical sensing and communication systems.

  19. Prototype of a Hybrid Cosmic Ray Detector at the Pico de Orizaba: First Stage

    Science.gov (United States)

    Ponce, E.; Salazar, H.; Martinez, O.; Moreno, E.; Pedraza, I.; Cotzomi, J.; Perez, E.; Villaseñor, L.; Khrenov, B.; Garipov, G.

    2003-07-01

    In this work we present a progress report of the project of a high energy cosmic ray observatory located at Pico de Orizaba mountain. One of the goals of this facility will be to contribute to the understanding of the origin of the cosmic rays at energies around the feature known as the knee. To achieve this goal we plan to use a hybrid detector composed of a surface detector array and a fluorescence telescope. The design and expected performance of the fluorescent detector is presented.

  20. Hybrid Model For Reverberant Indoor Radio Channels Using Rays and Graphs

    DEFF Research Database (Denmark)

    Steinböck, Gerhard; Gan, Mingming; Meissner, Paul

    2016-01-01

    efficient calculation of the channel transfer function considering infinitely many components. We use ray-tracing and the theory of room electromagnetics to obtain the parameter settings for the propagation graph. Thus the proposed hybrid model does not require new or additional parameters in comparison......Ray-tracing tools allow for deterministic simulation of the channel impulse response. Studies show that these tools work well when the impulse response consists only of a few distinct components. However, measurements of the channel impulse response in indoor environments show a diffuse tail...

  1. Adaptive Second Order Sliding Mode Control of a Fuel Cell Hybrid System for Electric Vehicle Applications

    Directory of Open Access Journals (Sweden)

    Jianxing Liu

    2015-01-01

    Full Text Available We present an adaptive-gain second order sliding mode (SOSM control applied to a hybrid power system for electric vehicle applications. The main advantage of the adaptive SOSM is that it does not require the upper bound of the uncertainty. The proposed hybrid system consists of a polymer electrolyte membrane fuel cell (PEMFC with a unidirectional DC/DC converter and a Li-ion battery stack with a bidirectional DC/DC converter, where the PEMFC is employed as the primary energy source and the battery is employed as the second energy source. One of the main limitations of the FC is its slow dynamics mainly due to the air-feed system and fuel-delivery system. Fuel starvation phenomenon will occur during fast load demand. Therefore, the second energy source is required to assist the main source to improve system perofrmance. The proposed energy management system contains two cascade control structures, which are used to regulate the fuel cell and battery currents to track the given reference currents and stabilize the DC bus voltage while satisfying the physical limitations. The proposed control strategy is evaluated for two real driving cycles, that is, Urban Dynamometer Driving Schedule (UDDS and Highway Fuel Economy Driving Schedule (HWFET.

  2. Beam-displacement ray-mode theory of sound propagation in shallow water

    Institute of Scientific and Technical Information of China (English)

    张仁和; 李风华

    1999-01-01

    A normal mode method for propagation modeling in common horizontally stratified shallow water, which is called beam-displacement ray-mode (BDRM) theory, is introduced. The peculiarity of this method is that the boundary effects on the sound field can be expressed by the equivalent boundary reflection coefficient, so BDRM theory can be extended to elastic bottom easily. Theoretical calculations of shallow-water sound field show that BDRM has high accuracy and fast speed. The pulse propagation in shallow water is also calculated by BDRM, and the calculated waveforms are in good agreement with the measured waveforms.

  3. A Geiger-mode avalanche photodiode array for X-ray photon correlation spectroscopy.

    Science.gov (United States)

    Johnson, I; Sadygov, Z; Bunk, O; Menzel, A; Pfeiffer, F; Renker, D

    2009-01-01

    X-ray photon correlation spectroscopy (XPCS) provides an opportunity to study the dynamics of systems by measuring the temporal fluctuations in a far-field diffraction pattern. A two-dimensional detector system has been developed to investigate fluctuations in the frequency range of several Hz to kHz. The X-ray detector system consists of a thin 100 microm scintillation crystal coupled to a Geiger-mode avalanche photodiode array. In this article the elements of the system are detailed and the detector for XPCS measurements is demonstrated.

  4. A deep campaign to characterize the synchronous radio/X-ray mode switching of PSR B0943+10

    CERN Document Server

    Mereghetti, S; Tiengo, A; Hessels, J; Hermsen, W; Stovall, K; Possenti, A; Rankin, J; Esposito, P; Turolla, R; Mitra, D; Wright, G; Stappers, B; Horneffer, A; Oslowski, S; Serylak, M; Griessmeier, J -M

    2016-01-01

    We report on simultaneous X-ray and radio observations of the mode-switching pulsar PSR B0943+10 obtained with the XMM-Newton satellite and the LOFAR, LWA and Arecibo radio telescopes in November 2014. We confirm the synchronous X-ray/radio switching between a radio-bright (B) and a radio-quiet (Q) mode, in which the X-ray flux is a factor ~2.4 higher than in the B-mode. We discovered X-ray pulsations, with pulsed fraction of 38+/-5% (0.5-2 keV), during the B-mode, and confirm their presence in Q-mode, where the pulsed fraction increases with energy from ~20% up to ~65% at 2 keV. We found marginal evidence for an increase in the X-ray pulsed fraction during B-mode on a timescale of hours. The Q-mode X-ray spectrum requires a fit with a two-component model (either a power-law plus blackbody or the sum of two blackbodies), while the B-mode spectrum is well fit by a single blackbody (a single power-law is rejected). With a maximum likelihood analysis, we found that in Q-mode the pulsed emission has a thermal bla...

  5. Study on H-mode access at low density with lower hybrid current drive and lithium-wall coatings on the EAST superconducting tokamak

    DEFF Research Database (Denmark)

    Xu, G.S.; Wan, B.N.; Li, J.G.

    2011-01-01

    The first high-confinement mode (H-mode) with type-III edge localized modes at an H factor of HIPB98(y,2) ~ 1 has been obtained with about 1 MW lower hybrid wave power on the EAST superconducting tokamak. The first H-mode plasma appeared after wall conditioning by lithium (Li) evaporation before ...

  6. Selective gating to vibrational modes through resonant X-ray scattering

    Science.gov (United States)

    Couto, Rafael C.; Cruz, Vinícius V.; Ertan, Emelie; Eckert, Sebastian; Fondell, Mattis; Dantz, Marcus; Kennedy, Brian; Schmitt, Thorsten; Pietzsch, Annette; Guimarães, Freddy F.; Ågren, Hans; Gel'Mukhanov, Faris; Odelius, Michael; Kimberg, Victor; Föhlisch, Alexander

    2017-01-01

    The dynamics of fragmentation and vibration of molecular systems with a large number of coupled degrees of freedom are key aspects for understanding chemical reactivity and properties. Here we present a resonant inelastic X-ray scattering (RIXS) study to show how it is possible to break down such a complex multidimensional problem into elementary components. Local multimode nuclear wave packets created by X-ray excitation to different core-excited potential energy surfaces (PESs) will act as spatial gates to selectively probe the particular ground-state vibrational modes and, hence, the PES along these modes. We demonstrate this principle by combining ultra-high resolution RIXS measurements for gas-phase water with state-of-the-art simulations.

  7. Asymptotic theory of gravity modes in rotating stars. I. Ray dynamics

    CERN Document Server

    Prat, Vincent; Ballot, Jérôme

    2015-01-01

    Context. The seismology of early-type stars is limited by our uncomplete understanding of gravito-inertial modes. Aims. We develop a short-wavelength asymptotic analysis for gravito-inertial modes in rotating stars. Methods. The Wentzel-Kramers-Brillouin approximation is applied to the equations governing adiabatic small perturbations about a model of uniformly rotating barotropic star. Results. A general eikonal equation, including the effect of the centrifugal deformation, is derived. The dynamics of axisymmetric gravito-inertial rays is solved numerically for polytropic stellar models of increasing rotation and analysed by describing the structure of the phase space. Three different types of phase space structures are distinguished. The first type results from the continuous evolution of structures of the non-rotating integrable phase space. It is predominant in the low-frequency part of the phase space. The second type of structures is island chains associated with stable periodic rays. The third type of ...

  8. Up to 400 GHz burst-mode pulse generation from a hybrid harmonic mode-locked Er-doped fibre laser

    Science.gov (United States)

    Wang, Sheng-Min; Lai, Yinchieh

    2017-02-01

    By inserting a birefringence filter with FSR  =  100 GHz inside a hybrid mode-locked Er-doped fibre laser, we successfully generate ps to sub-ps optical burst pulses with the intra-burst pulse rate up to 400 GHz. Multiplication of the intra-burst pulse rate is attributed to a new effect analogous to rational harmonic mode-locking, which occurs due to the relative alignment of the cavity harmonic frequencies, the external phase modulation induced frequencies, and the filter-selected frequencies.

  9. Biological sensing using hybridization phase of plasmonic resonances with photonic lattice modes in arrays of gold nanoantennas

    Science.gov (United States)

    Gutha, Rithvik R.; Sadeghi, Seyed M.; Sharp, Christina; Wing, Waylin J.

    2017-09-01

    We study biological sensing using the hybridization phase of localized surface plasmon resonances (LSPRs) with diffraction modes (photonic lattice modes) in arrays of gold nanoantennas. We map the degree of the hybridization process using an embedding dielectric material (Si), identifying the critical thicknesses wherein the optical responses of the arrays are mainly governed by pure LSPRs (insignificant hybridization), Fano-type coupling of LSPRs with diffraction orders (hybridization state), and their intermediate state (hybridization phase). The results show that hybridization phase can occur with slight change in the refractive index (RI), leading to sudden reduction of the linewidth of the main spectral feature of the arrays by about one order of magnitude while it is shifted nearly 140 nm. These processes, which offer significant improvement in RI sensitivity and figure of merit, are utilized to detect monolayers of biological molecules and streptavidin-conjugated semiconductor quantum dots with sensitivities far higher than pure LSPRs. We further explore how these sensors can be used based on the uncoupled LSPRs by changing the polarization of the incident light.

  10. AFM PeakForce QNM mode: Evidencing nanometre-scale mechanical properties of chitin-silica hybrid nanocomposites.

    Science.gov (United States)

    Smolyakov, G; Pruvost, S; Cardoso, L; Alonso, B; Belamie, E; Duchet-Rumeau, J

    2016-10-20

    PeakForce Quantitative Nanomechanical Mapping (QNM) AFM mode was used to explore the mechanical properties of textured chitin-silica hybrid films at the nanoscale. The influence of the force applied by the tip on the sample surface was studied for standard homogeneous samples, for chitin nanorods and for chitin-silica hybrid nanocomposites. Thick films of superimposed chitin nanorods showed a monotonous increase of DMT modulus (based on the Derjaguin-Muller-Toporov model) owing to an increase in modulus at the interface between nanorods due to geometrical constraints of the AFM acquisition. A similar variation of DMT modulus was obtained for chitin-silica hybrid thick films related to mechanical strengthening induced by the presence of silica. This work revealed the role of the organic-inorganic interface, at the nanoscale, in the mechanical behaviour of textured materials using PeakForce QNM mode, with optimized analysis conditions.

  11. Numerical investigations with a hybrid isentropic-sigma model. I - Normal-mode characteristics. II - The inclusion of moist processes

    Science.gov (United States)

    Pierce, R. B.; Johnson, Donald R.; Reames, Fred M.; Zapotocny, Tom H.; Wolf, Bart J.

    1991-01-01

    The normal-mode characteristics of baroclinically amplifying disturbances were numerically investigated in a series of adiabatic simulations by a hybrid isentropic-sigma model, demonstrating the effect of coupling an isentropic-coordinate free atmospheric domain with a sigma-coordinate PBL on the normal-mode characteristics. Next, the normal-mode model was modified by including a transport equation for water vapor and adiabatic heating by condensation. Simulations with and without a hydrological component showed that the overall effect of latent heat release is to markedly enhance cyclogenesis and frontogenesis.

  12. Design of Highly Efficient Hybrid Si-Au Taper for Dielectric Strip Waveguide to Plasmonic Slot Waveguide Mode Converter

    CERN Document Server

    Chen, Chin-Ta; Hosseini, Amir; Pan, Zeyu; Subbaraman, Harish; Zhang, Xingyu; Chen, Ray T

    2015-01-01

    In this paper, we design a dielectric-to-plasmonic slot waveguide mode converter based on the hybrid silicon-gold taper. The effects of mode matching, the effective index matching, and the metallic absorption loss on the conversion efficiency are studied. Consequently, a metallic taper-funnel coupler with an overall length of 1.7um is designed to achieve a very high conversion efficiency of 93.3% at 1550 nm. The configuration limitations for not allowing this mode converter to achieve a 100% conversion efficiency are also investigated. Such a high-efficiency converter can provide practical routes to realize ultracompact integrated circuits.

  13. High-Power Hybrid Mode-Locked External Cavity Semiconductor Laser Using Tapered Amplifier with Large Tunability

    Directory of Open Access Journals (Sweden)

    Andreas Schmitt-Sody

    2008-01-01

    Full Text Available We report on hybrid mode-locked laser operation of a tapered semiconductor amplifier in an external ring cavity, generating pulses as short as 0.5 ps at 88.1 MHz with an average power of 60 mW. The mode locking is achieved through a combination of a multiple quantum well saturable absorber (>10% modulation depth and an RF current modulation. This designed laser has 20 nm tuning bandwidth in continuous wave and 10 nm tuning bandwidth in mode locking around 786 nm center wavelength at constant temperature.

  14. The scaler mode in the Pierre Auger Observatory to study heliospheric modulation of cosmic rays

    CERN Document Server

    Dasso, S

    2012-01-01

    The impact of the solar activity on the heliosphere has a strong influence on the modulation of the flux of low energy galactic cosmic rays arriving at Earth. Different instruments, such as neutron monitors or muon detectors, have been recording the variability of the cosmic ray flux at ground level for several decades. Although the Pierre Auger Observatory was designed to observe cosmic rays at the highest energies, it also records the count rates of low energy secondary particles (the scaler mode) for the self-calibration of its surface detector array. From observations using the scaler mode at the Pierre Auger Observatory, modulation of galactic cosmic rays due to solar transient activity has been observed (e.g., Forbush decreases). Due to the high total count rate coming from the combined area of its detectors, the Pierre Auger Observatory (its detectors have a total area greater than $16\\,000$\\,m$^2$) detects a flux of secondary particles of the order of $\\sim 10^8$\\,counts per minute. Time variations of...

  15. The Solid State X-ray Image Intensifier (SSXII) in Single Photon Counting (SPC) mode.

    Science.gov (United States)

    Kuhls-Gilcrist, Andrew; Jain, Amit; Bednarek, Daniel R; Rudin, Stephen

    2010-03-22

    The new Solid State X-Ray Image Intensifier (SSXII) has the unique ability to operate in single photon counting (SPC) mode, with improved resolution, as well as in traditional energy integrating (EI) mode. The SSXII utilizes an electron-multiplying CCD (EMCCD), with an effective pixel size of 32μm, which enables variable signal amplification (up to a factor of 2000) prior to digital readout, providing very high-sensitivity capabilities. The presampled MTF was measured in both imaging modes using the standard angulated-slit method. A measured detector entrance exposure of 24μR per frame was used to provide approximately 0.8 interaction events per pixel in the 10μm-wide slit area. For demonstration purposes, a simple thresholding technique was used to localize events in SPC mode and a number of such frames were summed to provide an image with the same total exposure used for acquiring the EI image. The MTF for SPC mode, using a threshold level of 15% of the maximum 12-bit signal and 95% of the expected events, and for EI mode (in parentheses) was 0.67 (0.20), 0.37 (0.07), 0.20 (0.03), and 0.11 (0.01) at 2.5, 5, 7.5, and 10 cycles/mm, respectively. Increasing the threshold level resulted in a corresponding increase in the measured SPC MTF and a lower number of detected events, indicating a tradeoff between resolution and count efficiency is required. The SSXII in SPC mode was shown to provide substantial improvements in resolution relative to traditional EI mode, which should benefit applications that have demanding spatial resolution requirements, such as mammography.

  16. Exploring the Influence of Attitudes to Walking and Cycling on Commute Mode Choice Using a Hybrid Choice Model

    Directory of Open Access Journals (Sweden)

    Chuan Ding

    2017-01-01

    Full Text Available Transport-related problems, such as automobile dependence, traffic congestion, and greenhouse emissions, lead to a great burden on the environment. In developing countries like China, in order to improve the air quality, promoting sustainable travel modes to reduce the automobile usage is gradually recognized as an emerging national concern. Though there are many studies related to the physically active modes (e.g., walking and cycling, the research on the influence of attitudes to active modes on travel behavior is limited, especially in China. To fill up this gap, this paper focuses on examining the impact of attitudes to walking and cycling on commute mode choice. Using the survey data collected in China cities, an integrated discrete choice model and the structural equation model are proposed. By applying the hybrid choice model, not only the role of the latent attitude played in travel mode choice, but also the indirect effects of social factors on travel mode choice are obtained. The comparison indicates that the hybrid choice model outperforms the traditional model. This study is expected to provide a better understanding for urban planners on the influential factors of green travel modes.

  17. Mode identification using stochastic hybrid models with applications to conflict detection and resolution

    Science.gov (United States)

    Naseri Kouzehgarani, Asal

    2009-12-01

    Most models of aircraft trajectories are non-linear and stochastic in nature; and their internal parameters are often poorly defined. The ability to model, simulate and analyze realistic air traffic management conflict detection scenarios in a scalable, composable, multi-aircraft fashion is an extremely difficult endeavor. Accurate techniques for aircraft mode detection are critical in order to enable the precise projection of aircraft conflicts, and for the enactment of altitude separation resolution strategies. Conflict detection is an inherently probabilistic endeavor; our ability to detect conflicts in a timely and accurate manner over a fixed time horizon is traded off against the increased human workload created by false alarms---that is, situations that would not develop into an actual conflict, or would resolve naturally in the appropriate time horizon-thereby introducing a measure of probabilistic uncertainty in any decision aid fashioned to assist air traffic controllers. The interaction of the continuous dynamics of the aircraft, used for prediction purposes, with the discrete conflict detection logic gives rise to the hybrid nature of the overall system. The introduction of the probabilistic element, common to decision alerting and aiding devices, places the conflict detection and resolution problem in the domain of probabilistic hybrid phenomena. A hidden Markov model (HMM) has two stochastic components: a finite-state Markov chain and a finite set of output probability distributions. In other words an unobservable stochastic process (hidden) that can only be observed through another set of stochastic processes that generate the sequence of observations. The problem of self separation in distributed air traffic management reduces to the ability of aircraft to communicate state information to neighboring aircraft, as well as model the evolution of aircraft trajectories between communications, in the presence of probabilistic uncertain dynamics as well

  18. A hybrid approach to simulate multiple photon scattering in X-ray imaging

    Energy Technology Data Exchange (ETDEWEB)

    Freud, N. [CNDRI, Laboratory of Nondestructive Testing using Ionizing Radiations, INSA-Lyon Scientific and Technical University, Bat. Antoine de Saint-Exupery, 20, avenue Albert Einstein, 69621 Villeurbanne Cedex (France)]. E-mail: nicolas.freud@insa-lyon.fr; Letang, J.-M. [CNDRI, Laboratory of Nondestructive Testing using Ionizing Radiations, INSA-Lyon Scientific and Technical University, Bat. Antoine de Saint-Exupery, 20, avenue Albert Einstein, 69621 Villeurbanne Cedex (France); Babot, D. [CNDRI, Laboratory of Nondestructive Testing using Ionizing Radiations, INSA-Lyon Scientific and Technical University, Bat. Antoine de Saint-Exupery, 20, avenue Albert Einstein, 69621 Villeurbanne Cedex (France)

    2005-01-01

    A hybrid simulation approach is proposed to compute the contribution of scattered radiation in X- or {gamma}-ray imaging. This approach takes advantage of the complementarity between the deterministic and probabilistic simulation methods. The proposed hybrid method consists of two stages. Firstly, a set of scattering events occurring in the inspected object is determined by means of classical Monte Carlo simulation. Secondly, this set of scattering events is used as a starting point to compute the energy imparted to the detector, with a deterministic algorithm based on a 'forced detection' scheme. For each scattering event, the probability for the scattered photon to reach each pixel of the detector is calculated using well-known physical models (form factor and incoherent scattering function approximations, in the case of Rayleigh and Compton scattering respectively). The results of the proposed hybrid approach are compared to those obtained with the Monte Carlo method alone (Geant4 code) and found to be in excellent agreement. The convergence of the results when the number of scattering events increases is studied. The proposed hybrid approach makes it possible to simulate the contribution of each type (Compton or Rayleigh) and order of scattering, separately or together, with a single PC, within reasonable computation times (from minutes to hours, depending on the number of pixels of the detector). This constitutes a substantial benefit, compared to classical simulation methods (Monte Carlo or deterministic approaches), which usually requires a parallel computing architecture to obtain comparable results.

  19. X-ray Imaging Using a Hybrid Photon Counting GaAs Pixel Detector

    CERN Document Server

    Schwarz, C; Göppert, R; Heijne, Erik H M; Ludwig, J; Meddeler, G; Mikulec, B; Pernigotti, E; Rogalla, M; Runge, K; Smith, K M; Snoeys, W; Söldner-Rembold, S; Watt, J

    1999-01-01

    The performance of hybrid GaAs pixel detectors as X-ray imaging sensors were investigated at room temperature. These hybrids consist of 300 mu-m thick GaAs pixel detectors, flip-chip bonded to a CMOS Single Photon Counting Chip (PCC). This chip consists of a matrix of 64 x 64 identical square pixels (170 mu-m x 170 mu-m) and covers a total area of 1.2 cm**2. The electronics in each cell comprises a preamplifier, a discriminator with a 3-bit threshold adjust and a 15-bit counter. The detector is realized by an array of Schottky diodes processed on semi-insulating LEC-GaAs bulk material. An IV-charcteristic and a detector bias voltage scan showed that the detector can be operated with voltages around 200 V. Images of various objects were taken by using a standard X-ray tube for dental diagnostics. The signal to noise ratio (SNR) was also determined. The applications of these imaging systems range from medical applications like digital mammography or dental X-ray diagnostics to non destructive material testing (...

  20. Ultrafast Three-Dimensional X-ray Imaging of Deformation Modes in ZnO Nanocrystals.

    Science.gov (United States)

    Cherukara, Mathew J; Sasikumar, Kiran; Cha, Wonsuk; Narayanan, Badri; Leake, Steven J; Dufresne, Eric M; Peterka, Tom; McNulty, Ian; Wen, Haidan; Sankaranarayanan, Subramanian K R S; Harder, Ross J

    2017-02-08

    Imaging the dynamical response of materials following ultrafast excitation can reveal energy transduction mechanisms and their dissipation pathways, as well as material stability under conditions far from equilibrium. Such dynamical behavior is challenging to characterize, especially operando at nanoscopic spatiotemporal scales. In this letter, we use X-ray coherent diffractive imaging to show that ultrafast laser excitation of a ZnO nanocrystal induces a rich set of deformation dynamics including characteristic "hard" or inhomogeneous and "soft" or homogeneous modes at different time scales, corresponding respectively to the propagation of acoustic phonons and resonant oscillation of the crystal. By integrating the 3D nanocrystal structure obtained from the ultrafast X-ray measurements with a continuum thermo-electro-mechanical finite element model, we elucidate the deformation mechanisms following laser excitation, in particular, a torsional mode that generates a 50% greater electric potential gradient than that resulting from the flexural mode. Understanding of the time-dependence of these mechanisms on ultrafast scales has significant implications for development of new materials for nanoscale power generation.

  1. HYBRID CORDIC TRIGONOMETRIC VECTOR ROTATION MODE for AUTHENTICATING EAR and FINGER IMAGES

    Directory of Open Access Journals (Sweden)

    R. Parimala

    2015-10-01

    Full Text Available Security is a major issue as far as the use of computers is concerned. As computer technology is becoming more complex the problem of security is also becoming complex. The ingenuity of the human brain is such that for every innovation which has positive use there is also a parallel innovation in circumventing the positiveness of that use and it comes up with an antidote to that positivity. The problem of hackers and with the evolution of the idea of cloud computing security has become an important issue. In this paper we are primarily concerned with the problem of access control and authentication. As everyone knows biometrics is used for authentication in computer science. Biometrics identifies physical characteristics of the human beings that are distinctive to each individual and are easily measured. Among other things the popular physiological feature that has stood the test of time is finger print matching which is mostly used in forensic science. In recent years ear matching is also considered a possible physiological feature for authentication and identification of individuals. Now the question is how fool proof are these? In this paper we attempt to review recent literatures on these and applying Hybrid CORDIC Trigonometric Vector Rotation Mode algorithm and taking a pair of index fingers and a pair of ears as test cases we found better results in accuracy.

  2. The Andreev reflection of zero line mode in graphene-superconductor hybrid junction

    Science.gov (United States)

    Feng, Li; Cheng, Shu-guang

    2015-04-01

    The zero line mode (ZLM) in two dimensional materials provides a quasi-one dimensional path for electronic transport. We report the theoretical investigation of the Andreev reflection of ZLM by using the staggered graphene-superconductor based models. For a two-terminal system in which the valley index is well preserved, when graphene is zigzag edged, the Andreev reflection coefficient can be either large or strongly suppressed depending on the symmetric properties of the transverse wave function in graphene ribbon. However, the Andreev reflection coefficient, independent of the staggering profile in the armchair edged model, is large due to the absence of wave function symmetry. When ZLM changes its direction in a vertical path, a perfect Andreev reflection could happen when the incident ZLM stems from a zigzag edged graphene ribbon. In a zigzag edged four-terminal hybrid model, the interference of reflected holes leads to perfect Andreev reflection with probability unity and the annihilation of the crossed Andreev reflection. For the armchair edged model, the interference effect disappears because the Andreev reflection from one of the paths is prohibited. The interference of Andreev reflections in four-terminal models is investigated by spacial local density of states in the central scattering region as well.

  3. Isolator-free switchable uni- and bidirectional hybrid mode-locked erbium-doped fiber laser.

    Science.gov (United States)

    Chernysheva, Maria; Araimi, Mohammed Al; Kbashi, Hani; Arif, Raz; Sergeyev, Sergey V; Rozhin, Aleksey

    2016-07-11

    An Erbium-doped fibre ring laser hybrid mode-locked with single-wall carbon nanotubes (SWNT) and nonlinear polarisation evolution (NPE) without an optical isolator has been investigated for various cavity conditions. Precise control of the state of polarisation (SOP) in the cavity ensures different losses for counter-propagating optical fields. As the result, the laser operates in quasi-unidirectional regime in both clockwise (CW) and counter-clockwise (CCW) directions with the emission strengths difference of the directions of 22 dB. Furthermore, by adjusting the net birefringence in the cavity, the laser can operate in a bidirectional generation. In this case, a laser pumped with 75 mW power at 980 nm generates almost identical 790 and 570 fs soliton pulses with an average power of 1.17 and 1.11 mW. The operation stability and pulse quality of the soliton pulses in both unidirectional regimes are highly competitive with those generated in conventional ring fibre lasers with isolator in the cavity. Demonstrated bidirectional laser operation can find vital applications in gyroscopes or precision rotation sensing technologies.

  4. Hybrid Wing Body Shielding Studies Using an Ultrasonic Configurable Fan Artificial Noise Source Generating Simple Modes

    Science.gov (United States)

    Sutliff, Daniel, L.; Brown, Clifford, A.; Walker, Bruce, E.

    2012-01-01

    An Ultrasonic Configurable Fan Artificial Noise Source (UCFANS) was designed, built, and tested in support of the Langley Research Center s 14- by 22-Foot wind tunnel test of the Hybrid Wing Body (HWB) full three-dimensional 5.8 percent scale model. The UCFANS is a 5.8 percent rapid prototype scale model of a high-bypass turbofan engine that can generate the tonal signature of candidate engines using artificial sources (no flow). The purpose of the test was to provide an estimate of the acoustic shielding benefits possible from mounting the engine on the upper surface of an HWB aircraft and to provide a database for shielding code validation. A range of frequencies, and a parametric study of modes were generated from exhaust and inlet nacelle configurations. Radiated acoustic data were acquired from a traversing linear array of 13 microphones, spanning 36 in. Two planes perpendicular to the axis of the nacelle (in its 0 orientation) and three planes parallel were acquired from the array sweep. In each plane the linear array traversed five sweeps, for a total span of 160 in. acquired. The resolution of the sweep is variable, so that points closer to the model are taken at a higher resolution. Contour plots of Sound Pressure Level, and integrated Power Levels are presented in this paper; as well as the in-duct modal structure.

  5. KIC 10080943: An eccentric binary system containing two pressure- and gravity-mode hybrid pulsators

    Science.gov (United States)

    Schmid, V. S.; Tkachenko, A.; Aerts, C.; Degroote, P.; Bloemen, S.; Murphy, S. J.; Van Reeth, T.; Pápics, P. I.; Bedding, T. R.; Keen, M. A.; Prša, A.; Menu, J.; Debosscher, J.; Hrudková, M.; De Smedt, K.; Lombaert, R.; Németh, P.

    2015-12-01

    Context. γ Doradus and δ Scuti pulsators cover the transition region between low mass and massive main-sequence stars, and as such, are critical for testing stellar models. When they reside in binary systems, we can combine two independent methods to derive critical information, such as precise fundamental parameters to aid asteroseismic modelling. In the Kepler light curve of KIC 10080943, clear signatures of gravity- and pressure-mode pulsations have been found. Ground-based spectroscopy revealed this target to be a double-lined binary system. Aims: We present the analysis of four years of Kepler photometry and high-resolution spectroscopy to derive observational constraints with which to evaluate theoretical predictions of the stellar structure and evolution for intermediate-mass stars. Methods: We used the method of spectral disentangling to determine atmospheric parameters for both components and derive the orbital elements. With phoebe, we modelled the ellipsoidal variation and reflection signal of the binary in the light curve and used classical Fourier techniques to analyse the pulsation modes. Results: We show that the eccentric binary system KIC 10080943 contains two hybrid pulsators with masses M1 = 2.0 ± 0.1 M⊙ and M2 = 1.9 ± 0.1 M⊙, with radii R1 = 2.9 ± 0.1 R⊙ and R2 = 2.1 ± 0.2 R⊙. We detect rotational splitting in the g and p modes for both stars and use them to determine a first rough estimate of the core-to-surface rotation rates for the two components, which will be improved by future detailed seismic modelling. Based on the data gathered with NASA's Discovery mission, Kepler, and with the HERMES spectrograph, installed at the Mercator Telescope, operated on the island of La Palma by the Flemish Community, at the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrofísica de Canarias and supported by the Fund for Scientific Research of Flanders (FWO), Belgium, the Research Council of KU Leuven, Belgium, the

  6. Mode-Locked Multichromatic X-Rays in a Seeded Free-Electron Laser for Single-Shot X-Ray Spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Xiang, Dao; Ding, Yuantao; Raubenheimer, Tor; Wu, Juhao; /SLAC

    2012-05-10

    We present the promise of generating gigawatt mode-locked multichromatic x rays in a seeded free-electron laser (FEL). We show that, by using a laser to imprint periodic modulation in electron beam phase space, a single-frequency coherent seed can be amplified and further translated to a mode-locked multichromatic output in an FEL. With this configuration the FEL output consists of a train of mode-locked ultrashort pulses which span a wide frequency gap with a series of equally spaced sharp lines. These gigawatt multichromatic x rays may potentially allow one to explore the structure and dynamics of a large number of atomic states simultaneously. The feasibility of generating mode-locked x rays ranging from carbon K edge ({approx}284 eV) to copper L{sub 3} edge ({approx}931 eV) is confirmed with numerical simulation using the realistic parameters of the linac coherent light source (LCLS) and LCLS-II. We anticipate that the mode-locked multichromatic x rays in FELs may open up new opportunities in x-ray spectroscopy (i.e. resonant inelastic x-ray scattering, time-resolved scattering and spectroscopy, etc.).

  7. Mode-Locked Multichromatic X-Rays in a Seeded Free-Electron Laser for Single-Shot X-Ray Spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Xiang, Dao; Ding, Yuantao; Raubenheimer, Tor; Wu, Juhao; /SLAC

    2012-05-10

    We present the promise of generating gigawatt mode-locked multichromatic x rays in a seeded free-electron laser (FEL). We show that, by using a laser to imprint periodic modulation in electron beam phase space, a single-frequency coherent seed can be amplified and further translated to a mode-locked multichromatic output in an FEL. With this configuration the FEL output consists of a train of mode-locked ultrashort pulses which span a wide frequency gap with a series of equally spaced sharp lines. These gigawatt multichromatic x rays may potentially allow one to explore the structure and dynamics of a large number of atomic states simultaneously. The feasibility of generating mode-locked x rays ranging from carbon K edge ({approx}284 eV) to copper L{sub 3} edge ({approx}931 eV) is confirmed with numerical simulation using the realistic parameters of the linac coherent light source (LCLS) and LCLS-II. We anticipate that the mode-locked multichromatic x rays in FELs may open up new opportunities in x-ray spectroscopy (i.e. resonant inelastic x-ray scattering, time-resolved scattering and spectroscopy, etc.).

  8. Assessment of asthmatic inflammation using hybrid fluorescence molecular tomography-x-ray computed tomography

    Science.gov (United States)

    Ma, Xiaopeng; Prakash, Jaya; Ruscitti, Francesca; Glasl, Sarah; Stellari, Fabio Franco; Villetti, Gino; Ntziachristos, Vasilis

    2016-01-01

    Nuclear imaging plays a critical role in asthma research but is limited in its readings of biology due to the short-lived signals of radio-isotopes. We employed hybrid fluorescence molecular tomography (FMT) and x-ray computed tomography (XCT) for the assessment of asthmatic inflammation based on resolving cathepsin activity and matrix metalloproteinase activity in dust mite, ragweed, and Aspergillus species-challenged mice. The reconstructed multimodal fluorescence distribution showed good correspondence with ex vivo cryosection images and histological images, confirming FMT-XCT as an interesting alternative for asthma research.

  9. Waves and rays in plano-concave laser cavities: I. Geometric modes in the paraxial approximation

    Science.gov (United States)

    Barré, N.; Romanelli, M.; Lebental, M.; Brunel, M.

    2017-05-01

    Eigenmodes of laser cavities are studied theoretically and experimentally in two companion papers, with the aim of making connections between undulatory and geometric properties of light. In this first paper, we focus on macroscopic open-cavity lasers with localized gain. The model is based on the wave equation in the paraxial approximation; experiments are conducted with a simple diode-pumped Nd:YAG laser with a variable cavity length. After recalling fundamentals of laser beam optics, we consider plano-concave cavities with on-axis or off-axis pumping, with emphasis put on degenerate cavity lengths, where modes of different order resonate at the same frequency, and combine to form surprising transverse beam profiles. Degeneracy leads to the oscillation of so-called geometric modes whose properties can be understood, to a certain extent, also within a ray optics picture. We first provide a heuristic description of these modes, based on geometric reasoning, and then show more rigorously how to derive them analytically by building wave superpositions, within the framework of paraxial wave optics. The numerical methods, based on the Fox-Li approach, are described in detail. The experimental setup, including the imaging system, is also detailed and relatively simple to reproduce. The aim is to facilitate implementation of both the numerics and of the experiments, and to show that one can have access not only to the common higher-order modes but also to more exotic patterns.

  10. Hard X-ray optics simulation using the coherent mode decomposition of Gaussian Schell model

    CERN Document Server

    Hua, Wenqiang; Song, Li; Li, Xiuhong; Wang, Jie

    2013-01-01

    The propagation of hard X ray beam from partially coherent synchrotron source is simulated by using the novel method based on the coherent mode decomposition of Gaussian Schell model and wave front propagation. We investigate how the coherency properties and intensity distributions of the beam are changed by propagation through optical elements. Here, we simulate and analyze the propagation of the partially coherent radiation transmitted through an ideal slit. We present the first simulations for focusing partially coherent synchrotron hard X ray beams using this novel method. And when compared with the traditional method which assumes the source is a totally coherent point source or completely incoherent, this method is proved to be more reasonable and can also demonstrate the coherence properties of the focusing beam. We also simulate the double slit experiment and the simulated results validate the academic analysis.

  11. Shimming with permanent magnets for the x-ray detector in a hybrid x-ray/ MR system.

    Science.gov (United States)

    Wen, Zhifei; Fahrig, Rebecca; Williams, Scott T; Pelc, Norbert J

    2008-09-01

    In this x-ray/MR hybrid system an x-ray flat panel detector is placed under the patient cradle, close to the MR volume of interest (VOI), where the magnetic field strength is approximately 0.5 T. Immersed in this strong field, several electronic components inside the detector become magnetized and create an additional magnetic field that is superimposed on the original field of the MR scanner. Even after linear shimming, the field homogeneity of the MR scanner remains disrupted by the detector. The authors characterize the field due to the detector with the field of two magnetic dipoles and further show that two sets of permanent magnets (NdFeB) can withstand the main magnetic field and compensate for the nonlinear components of the additional field. The ideal number of magnets and their locations are calculated based on a field map measured with the detector in place. Experimental results demonstrate great promise for this technique, which may be useful in many settings where devices with magnetic components need to be placed inside or close to an MR scanner.

  12. Magneto-optical mode conversion in a hybrid glass waveguide made by sol-gel and ion-exchange techniques

    Science.gov (United States)

    Royer, François; Amata, Hadi; Parsy, François; Jamon, Damien; Ghibaudo, Elise; Broquin, Jean-Emmanuel; Neveu, Sophie

    2012-01-01

    The integration of magneto-optical materials with classical technologies being still a difficult problem, this study explores the possibility to realize a mode converter based on a hybrid structure. A composite magneto-optical layer made of a silica/zirconia matrix doped by magnetic nanoparticles is coated on the top face of ion-exchanged glass waveguides. Optical characterizations that have been carried out demonstrated the efficiency of these hybrid structures in terms of lateral confinement. Furthermore, TE to TM mode conversion has been observed when a longitudinal magnetic field is applied to the device. The amount of this conversion is analysed taking into account the magneto-optical confinement and the modal birefringence of the structure.

  13. Modification of ordinary-mode reflectometry system to detect lower-hybrid waves in Alcator C-Moda)

    Science.gov (United States)

    Baek, S. G.; Shiraiwa, S.; Parker, R. R.; Dominguez, A.; Kramer, G. J.; Marmar, E. S.

    2012-10-01

    Backscattering experiments to detect lower-hybrid (LH) waves have been performed in Alcator C-Mod, using the two modified channels (60 GHz and 75 GHz) of an ordinary-mode reflectometry system with newly developed spectral recorders that can continuously monitor spectral power at a target frequency. The change in the baseline of the spectral recorder during the LH wave injection is highly correlated to the strength of the X-mode non-thermal electron cyclotron emission. In high density plasmas where an anomalous drop in the lower hybrid current drive efficiency is observed, the observed backscattered signals are expected to be generated near the last closed flux surface, demonstrating the presence of LH waves within the plasma. This experimental technique can be useful in identifying spatially localized LH electric fields in the periphery of high-density plasmas.

  14. Towards hybrid pixel detectors for energy-dispersive or soft X-ray photon science.

    Science.gov (United States)

    Jungmann-Smith, J H; Bergamaschi, A; Brückner, M; Cartier, S; Dinapoli, R; Greiffenberg, D; Huthwelker, T; Maliakal, D; Mayilyan, D; Medjoubi, K; Mezza, D; Mozzanica, A; Ramilli, M; Ruder, Ch; Schädler, L; Schmitt, B; Shi, X; Tinti, G

    2016-03-01

    JUNGFRAU (adJUstiNg Gain detector FoR the Aramis User station) is a two-dimensional hybrid pixel detector for photon science applications at free-electron lasers and synchrotron light sources. The JUNGFRAU 0.4 prototype presented here is specifically geared towards low-noise performance and hence soft X-ray detection. The design, geometry and readout architecture of JUNGFRAU 0.4 correspond to those of other JUNGFRAU pixel detectors, which are charge-integrating detectors with 75 µm × 75 µm pixels. Main characteristics of JUNGFRAU 0.4 are its fixed gain and r.m.s. noise of as low as 27 e(-) electronic noise charge (X-ray irradiation from an X-ray tube and a synchrotron light source are successfully demonstrated with an r.m.s. energy resolution of 20% (no mask) and 14% (with the mask) at 1.2 keV and of 5% at 13.3 keV. The performance evaluation of the JUNGFRAU 0.4 prototype suggests that this detection system could be the starting point for a future detector development effort for either applications in the soft X-ray energy regime or for an energy-dispersive detection system.

  15. Improved performance of Li-ion cells under pulsed load using double-layer capacitors in a hybrid circuit mode

    Energy Technology Data Exchange (ETDEWEB)

    ROTH,EMANUEL P.; NAGASUBRAMANIAN,GANESAN

    2000-02-07

    Electrical characteristics of hybrid power sources consisting of Li-ion cells and double-layer capacitors were studied at 25 C and {minus}20 C. The cells were initially evaluated for pulse performance and then measured in hybrid modes of operation where they were coupled with the high-power capacitors. Cells manufactured by Panasonic measured at 25 C delivered full capacities of 0.76 Ah for pulses up to 3A and cells from A and T delivered full capacities of 0.73 Ah for pulses up to 4A. Measured cell resistances were 0.15 ohms and 0.12 ohms, respectively. These measurements were repeated at {minus}20 C. Direct coupling of the cells and capacitors (coupled hybrid) using 10F Panasonic capacitors in a 8F series/parallel combination extended the full capacity pulse limits (3.0V threshold) to 5.6A for the Panasonic cells and to 9A for the A and T cells. A similar arrangement using 100F capacitors from Elna in a 60F combination increased the Panasonic cell limit to 10 A. Operation in an uncoupled hybrid mode using uncoupled cell/capacitor discharge allowed fill cell capacity usage at 25 C up to the capacitor discharge limit and showed a factor of 5 improvement in delivered capacity at {minus}20 C.

  16. Comparison of CCD, CMOS and Hybrid Pixel x-ray detectors: detection principle and data quality

    Science.gov (United States)

    Allé, P.; Wenger, E.; Dahaoui, S.; Schaniel, D.; Lecomte, C.

    2016-06-01

    We compare, from a crystallographic point of view, the data quality obtained using laboratory x-ray diffractometers equipped with a Molybdenum micro-source using different detector types: CCD, CMOS and XPAD hybrid pixel. First we give an overview of the working principle of these different detector types with a focus on their principal differences and their impact on the data quality. Then, using the example of an organic crystal, a comparison between the detector systems concerning the raw data statistics, the refinement agreement factors, the deformation electron density maps, and the residual density after multipolar refinement is presented. It is found that the data quality obtained with the XPAD detector is the best, even though the detection efficiency at the Mo energy (17.5 keV) is only 37% due to the Si-sensor layer thickness of 300 μm. Finally, we discuss the latest x-ray detector developments with an emphasis on the sensor material, where replacing Si by another material such as GaAs would yield detection efficiencies close to 100%, up to energies of 40 keV for hybrid pixel detectors.

  17. Research on a Novel Exciting Method for a Sandwich Transducer Operating in Longitudinal-Bending Hybrid Modes.

    Science.gov (United States)

    Liu, Yingxiang; Shen, Qiangqiang; Shi, Shengjun; Deng, Jie; Chen, Weishan; Wang, Liang

    2017-06-27

    A novel exciting method for a sandwich type piezoelectric transducer operating in longitudinal-bending hybrid vibration modes is proposed and discussed, in which the piezoelectric elements for the excitations of the longitudinal and bending vibrations share the same axial location, but correspond to different partitions. Whole-piece type piezoelectric plates with three separated partitions are used, in which the center partitions generate the first longitudinal vibration, while the upper and lower partitions produce the second bending vibration. Detailed comparisons between the proposed exciting method and the traditional one were accomplished by finite element method (FEM) calculations, which were further verified by experiments. Compared with the traditional exciting method using independent longitudinal ceramics and bending ceramics, the proposed method achieves higher electromechanical coupling factors and larger vibration amplitudes, especially for the bending vibration mode. This novel exciting method for longitudinal-bending hybrid vibrations has not changed the structural dimensions of the sandwich transducer, but markedly improves the mechanical output ability, which makes it very helpful and meaningful in designing new piezoelectric actuators operated in longitudinal-bending hybrid vibration modes.

  18. Design of hybrid sol gel films for direct x-ray and electron beam nanopatterning

    Science.gov (United States)

    Brusatin, Giovanna; Della Giustina, Gioia; Romanato, Filippo; Guglielmi, Massimo

    2008-04-01

    New epoxy based sol-gel organic inorganic materials, showing lithographic resist-like properties without the addition of any photocatalysts, are presented. To obtain a material sensitive to radiation, specific sol-gel syntheses based on an organically modified alkoxide containing an epoxy ring, 3-glycidoxypropyltrimethoxysilane (GPTMS), have been developed. The synthesis and the patternability of hybrid materials have been obtained controlling the inorganic crosslinking degree and with an almost total absence of organic polymerization. Two examples of directly patternable hybrid films, called GB and GGe, have been synthesized using acidic (GGe) and basic (GB) conditions and obtaining different compositions. After electron beam lithography (EBL) or x-ray synchrotron radiation lithography (XRL) the polymerization of the organic component of the sol-gel film occurs, generating a hardening of the structure after post-exposure baking. The exposed polymerized material becomes insoluble, determining a negative resist-like behaviour of the film: the lithographic process of nanopatterning results from the dissolution of the unexposed areas in proper solvents (developers). Spatial resolution of the order of 200 nm is reported and a contrast of 2.2 is achieved. The novelty of this work is that epoxy based materials, which have enhanced thermomechanical stability with respect to the more usual acrylic based resins, are directly nanopatterned for the first time by electron beam (EB) and/or x-ray beam radiation exposure without the aid of catalysts for polymerization. In contrast to common resists that are sacrificial layers of the fabrication process, direct patternable sol-gel hybrids constitute the final material of the devices. In fact, an example of doping with a light emitting dye is reported together with the achievement of directly patterned structures by EBL and XRL.

  19. A Hybrid Circuit for Spoof Surface Plasmons and Spatial Waveguide Modes to Reach Controllable Band-Pass Filters.

    Science.gov (United States)

    Zhang, Qian; Zhang, Hao Chi; Wu, Han; Cui, Tie Jun

    2015-11-10

    We propose a hybrid circuit for spoof surface plasmon polaritons (SPPs) and spatial waveguide modes to develop new microwave devices. The hybrid circuit includes a spoof SPP waveguide made of two anti-symmetric corrugated metallic strips and a traditional substrate integrated waveguide (SIW). From dispersion relations, we show that the electromagnetic waves only can propagate through the hybrid circuit when the operating frequency is less than the cut-off frequency of the SPP waveguide and greater than the cut-off frequency of SIW, generating efficient band-pass filters. We demonstrate that the pass band is controllable in a large range by designing the geometrical parameters of SPP waveguide and SIW. Full-wave simulations are provided to show the large adjustability of filters, including ultra wideband and narrowband filters. We fabricate a sample of the new hybrid device in the microwave frequencies, and measurement results have excellent agreements to numerical simulations, demonstrating excellent filtering characteristics such as low loss, high efficiency, and good square ratio. The proposed hybrid circuit gives important potential to accelerate the development of plasmonic integrated functional devices and circuits in both microwave and terahertz frequencies.

  20. Coherence filtering and revivals in x-ray waveguides: a communication-modes approach.

    Science.gov (United States)

    Pelliccia, Daniele; Paganin, David M

    2014-08-01

    Waveguides for short-wavelength x-rays have been successfully employed for microbeam and nanobeam production and microscopy experiments. The coherence of hard x-ray sources is generally poor, and therefore the spatial coherence filtering characteristics of waveguides have been attractive for high-resolution microscopy experiments. To quantify the spatial coherence filtering properties of a waveguide, we here report a theoretical study of the propagation of a partially coherent beam in a waveguide in the paraxial approximation. By propagating the cross-spectral density function associated with the partially coherent field, we quantify in detail the evolution of the spatial coherence as the beam proceeds along the waveguide. The propagation is efficiently accomplished using the communication-modes formalism. The generality of the approach makes it suitable to study more complex phenomena such as the second-order Talbot self-imaging effect and coherence revivals in waveguides. Numerical results are shown for waveguides illuminated by partially coherent hard x-rays.

  1. Timing accuracy of the Swift X-Ray Telescope in WT mode

    CERN Document Server

    Cusumano, G; Capalbi, M; Perri, M; Beardmore, A P; Burrows, D N; Campana, S; Kennea, J A; Osborne, J P; Sbarufatti, B; Tagliaferri, G

    2012-01-01

    The X-Ray Telescope (XRT) on board Swift was mainly designed to provide detailed position, timing and spectroscopic information on Gamma-Ray Burst (GRB) afterglows. During the mission lifetime the fraction of observing time allocated to other types of source has been steadily increased. In this paper, we report on the results of the in-flight calibration of the timing capabilities of the XRT in Windowed Timing read-out mode. We use observations of the Crab pulsar to evaluate the accuracy of the pulse period determination by comparing the values obtained by the XRT timing analysis with the values derived from radio monitoring. We also check the absolute time reconstruction measuring the phase position of the main peak in the Crab profile and comparing it both with the value reported in literature and with the result that we obtain from a simultaneous Rossi X-Ray Timing Explorer (RXTE) observation. We find that the accuracy in period determination for the Crab pulsar is of the order of a few picoseconds for the...

  2. Single-mode surface-emitting distributed feedback quantum-cascade lasers based on hybrid waveguide structure

    Institute of Scientific and Technical Information of China (English)

    Wanhong Guo; Junqi Liu; Jianyan Chen; Lu Li; Lijun Wang; Fengqi Liu; Zhanguo Wang

    2011-01-01

    Surface-emitting distributed feedback quantum-cascade lasers operating at λ≈7.8 μm are demonstrated.The metal-covered second-order grating is shallow-etched into the surface of a thin InGaAs contact and cladding layer. This forms a hybrid waveguide and used to achieve relatively low waveguide losses and high coupling strengths. The devices exhibit stable single-mode operation from 90 to 130 K with a side mode suppression ratio above 20 dB. A slope efficiency of 194 mW/A is obtained at 90 K, which is twice higher than that of the Fabry-Perot counterpart.%@@ Surface-emitting distributed feedback quantum-cascade lasers operating at λ≈7.8 μm are demonstrated.The metal-covered second-order grating is shallow-etched into the surface of a thin InGaAs contact and cladding layer.This forms a hybrid waveguide and used to achieve relatively low waveguide losses and high coupling strengths.The devices exhibit stable single-mode operation from 90 to 130 K with a side mode suppression ratio above 20 dB.A slope efficiency of 194 mW/A is obtained at 90 K, which is twice higher than that of the Fabry-Perot counterpart.

  3. Output feedback hybrid-impulsive second order sliding mode control: Lyapunov approach

    NARCIS (Netherlands)

    Shtessel, Y.; Glumineau, A.; Plestan, F.; Weiss, M.

    2014-01-01

    A perturbed nonlinear system of relative degree two controlled by output feedbacks discontinuous-hybrid-impulsive control is studied. The output hybrid-impulsive terms serve to drive instantaneously the system's trajectory to the origin or to its small vicinity. The output feedback impulsive action

  4. Hybrid Extensive Air Shower Detector Array at the University of Puebla to Study Cosmic Rays

    Science.gov (United States)

    Martínez, O.; Pérez, E.; Salazar, H.; Villaseñor, L.

    We describe the design of an extensive air shower detector array built in the Campus of the University of Puebla (located at 19°N, 90°W, 800 gcm -2) to measure the energy and arrival direction of primary cosmic rays with energies around 1015 eV. The array consists of 18 liquid scintillator detectors (12 in the first stage) and 6 water Cherenkov detectors (one of 10 m 2 cross section and five smaller ones of 1.86 m 2 cross section), distributed in a square grid with a detector spacing of 20 m over an area of 4000 m 2. In this paper we discuss the calibration and stability of the array, and discuss the capability of hybrid arrays, such as this one consisting of water Cherenkov and liquid scintillator detectors, to allow a separation of the electromagnetic and muon components of extensive air showers. This separation plays an important role in the determination of the mass and identity of the primary cosmic ray. This facility is also used to train students interested in the field of cosmic rays.

  5. Performance of the Full-scale Loop Hybrid Reactor Treating Coal Gasification Wastewater under Different Recirculation Modes

    Institute of Scientific and Technical Information of China (English)

    Qian Zhao; Hongjun Han; Fang Fang; Wang Bing

    2015-01-01

    This paper aims to investigate the simultaneous removal efficiencies of both COD and nitrogen in a single reactor treating coal gasification wastewater ( CGW ) . A novel loop hybrid reactor was developed and operated under different recirculation modes in order to achieve simultaneous removal of refractory compounds and total nitrogen ( TN) in a full⁃scale CGW treatment plant. Mid⁃ditch recirculation was superior to other operational modes in terms of the NH3⁃N and TN removal, resulting in a TN removal efficiency of 52. 3%. Although the system achieved equal COD removal rates under different recirculation modes, hydrophobic acid ( HPO⁃A) fraction of effluent dissolved organic matter ( DOMef) in mid⁃ditch recirculation mode accounted for 35.7%, compared to the proportions of 59. 2%, 45. 3% and 39. 4% for the other modes. The ultraviolet absorbance to dissolved organic carbon ratio test revealed that effluent under mid⁃ditch recirculation mode contained more non⁃aromatic hydrophilic components. Furthermore, appropriate recirculation and anoxic/oxic ( A/O) partitions were also demonstrated to remove some refractory metabolites ( phenols, alkanes, aniline, etc.), which reduced the chromaticity and improved the biodegradability.

  6. Communication: Effect of accidental mode degeneracy on Raman intensity in 2D materials: Hybrid functional study of bilayer phosphorene

    Science.gov (United States)

    Sun, Yi-Yang; Zhang, Shengbai

    2016-07-01

    Bulk black phosphorus has two optical phonon modes labeled as Ag2 and B2u, respectively, that are nearly degenerate in frequency. However, density functional theory calculations using local or semi-local functionals cannot reproduce this degeneracy. Here, we propose a hybrid functional approach aided by van der Waals (vdW) force fields, which can accurately describe the lattice dynamic and electronic properties of both bulk and few-layer black phosphorus (phosphorene). Using this approach we show that in bilayer phosphorene, the two Raman modes derived from the B2u and Ag2 modes could exhibit strong resonance as a result of the accidental degeneracy so that both modes could be observed in Raman experiment. Without the mode degeneracy, however, the Raman intensity of the B2u-derived mode would be too weak to be observed. We further show that the accidental degeneracy is correlated to the applied strain, which enables Raman spectroscopy to be a powerful tool for characterizing built-in strains in 2D materials, e.g., due to the interaction with substrates, which has emerged as an important issue in vdW epitaxy.

  7. Communication: Effect of accidental mode degeneracy on Raman intensity in 2D materials: Hybrid functional study of bilayer phosphorene.

    Science.gov (United States)

    Sun, Yi-Yang; Zhang, Shengbai

    2016-07-14

    Bulk black phosphorus has two optical phonon modes labeled as Ag (2) and B2u, respectively, that are nearly degenerate in frequency. However, density functional theory calculations using local or semi-local functionals cannot reproduce this degeneracy. Here, we propose a hybrid functional approach aided by van der Waals (vdW) force fields, which can accurately describe the lattice dynamic and electronic properties of both bulk and few-layer black phosphorus (phosphorene). Using this approach we show that in bilayer phosphorene, the two Raman modes derived from the B2u and Ag (2) modes could exhibit strong resonance as a result of the accidental degeneracy so that both modes could be observed in Raman experiment. Without the mode degeneracy, however, the Raman intensity of the B2u-derived mode would be too weak to be observed. We further show that the accidental degeneracy is correlated to the applied strain, which enables Raman spectroscopy to be a powerful tool for characterizing built-in strains in 2D materials, e.g., due to the interaction with substrates, which has emerged as an important issue in vdW epitaxy.

  8. Pneumatic-Combustion Hybrid Engine: A Study of the Effect of the Valvetrain Sophistication on Pneumatic Modes Moteur hybride pneumatique: une étude de l’effet de la complexité de la distribution sur les modes pneumatiques

    Directory of Open Access Journals (Sweden)

    Brejaud P.

    2009-09-01

    Full Text Available Although internal combustion engines display high overall maximum global efficiencies, this potential cannot be fully exploited in automotive applications: in real conditions, the average engine load (and thus efficiency is quite low and the kinetic energy during a braking phase is lost. This work presents a hybrid pneumatic-combustion engine and the associated thermodynamic cycles, which is able to store and recover energy in the form of compressed air. The study focuses on the two major pneumatic modes: pneumatic pump mode and pneumatic motor mode. For each of them, three valvetrain technologies are considered: 4-stroke mode, 4-stroke mode with one camshaft disengaged, and 2-stroke fully variable. The concept can be adapted to SI or CI engines. In any case the valvetrain technology is the key to best fuel economy. A kinematic model of the charging valve’s actuator is introduced, and implemented in a quasi dimensional model of the pneumatic-combustion hybrid engine. Simulation results are presented for each pneumatic mode, for each valvetrain technology, in order to determine the best valve train configuration, and to show the impact of the kinematic valve actuator on the performance of the engine The tradeoffs between valvetrain sophistication and fuel economy will be presented for each case. Bien que le rendement total d’un moteur à combustion interne soit élevé, ce potentiel ne peut être pleinement exploité sur une automobile : dans les conditions réelles d’utilisation, la charge moteur moyenne (et donc le rendement est souvent faible. De plus, l’énergie cinétique en phase de freinage est totalement dissipée sous forme de chaleur. Cet article présente un concept de moteur hybride pneumatique, et les cycles thermodynamiques associés, capable de stocker de l’énergie (et de la réutiliser sous forme d’air comprimé. Le concept est adaptable au moteur à allumage commandé aussi bien qu’au moteur à allumage par

  9. A hybrid model of anaerobic E. coli GJT001: combination of elementary flux modes and cybernetic variables.

    Science.gov (United States)

    Kim, Jin Il; Varner, Jeffery D; Ramkrishna, Doraiswami

    2008-01-01

    Flux balance analysis (FBA) in combination with the decomposition of metabolic networks into elementary modes has provided a route to modeling cellular metabolism. It is dependent, however, on the availability of external fluxes such as substrate uptake or growth rate before estimates can become available of intracellular fluxes. The framework classically does not allow modeling of metabolic regulation or the formulation of dynamic models except through dynamic measurement of external fluxes. The cybernetic modeling approach of Ramkrishna and coworkers provides a dynamic framework for modeling metabolic systems because of its focus on describing regulatory processes based on cybernetic arguments and hence has the capacity to describe both external and internal fluxes. In this article, we explore the alternative of developing hybrid models combining cybernetic models for the external fluxes with the flux balance approach for estimation of the internal fluxes. The approach has the merit of the simplicity of the early cybernetic models and hence computationally facile while also providing detailed information on intracellular fluxes. The hybrid model of this article is based on elementary mode decomposition of the metabolic network. The uptake rates for the various elementary modes are combined using global cybernetic variables based on maximizing substrate uptake rates. Estimation of intracellular metabolism is based on its stoichiometric coupling with the external fluxes under the assumption of (pseudo-) steady state conditions. The set of parameters of the hybrid model was estimated with the aid of nonlinear optimization routine, by fitting simulations with dynamic experimental data on concentrations of biomass, substrate, and fermentation products. The hybrid model estimations were tested with FBA (based on measured substrate uptake rate) for two different metabolic networks (one is a reduced network which fixes ATP contribution to the biomass and maintenance

  10. Impulse Response of a 36-Core Few-Mode Photonic Lantern Hybrid Spatial-Multiplexer

    DEFF Research Database (Denmark)

    Rommel, Simon; Mendinueta, José Manuel Delgado; Klaus, Werner

    2017-01-01

    Space division multiplexing (SDM) using fibers with multiple cores and/or supporting multiple modes has become an essential technology to support Pbit/s transmissions in a single fiber [1,2]. Despite significant mode-mixing in few-mode fibers (FMF), the original signals can be recovered through...

  11. Improved confinement in ELM-suppressed high-density H-modes at the ITER field via modification of the plasma boundary with Lower Hybrid RF

    Science.gov (United States)

    Terry, J. L.

    2014-10-01

    Injecting Lower Hybrid (LH) power into Alcator C-Mod's high-density H-mode plasmas has enhanced global confinement by increasing pedestal temperature gradients, modifying edge rotation, and decreasing edge and SOL turbulence. These new experiments indicate that edge LHRF can be used as a tool to increase confinement via direct modification of boundary quantities. Ray-tracing modeling and accessibility calculations for the LH waves indicate that the LH waves do not penetrate to regions inside the top of the pedestal and are not driving current in these plasmas; instead the LH power modifies the boundary conditions. When moderate amounts of LH power (PLH/Ptot = 20%) are applied to high-density EDA H-modes (neo = 3.5×1020 m-3) , we observe the following effects: edge/SOL fluctuation power decreases by roughly an order of magnitude; pedestal temperature gradients are increased; global energy confinement time and H-factor increase by 30-40% (H98 from 0.7 to 1.0); co-current core and pedestal rotation velocities increase; power to the (outer) divertor target increases promptly with an increment that is roughly 1/2 of the injected LH power, qualitatively consistent with the inaccessibility of the LH waves; and the central frequency of the edge-localized Quasi-Coherent Mode down-shifts and becomes much more coherent. These H-mode confinement improvements brought about by the edge LHRF are the result of changes in the pedestal (e.g. changes in rotation/shear and increased pedestal temperature gradients), with no substantial change in peaking of core density or temperature profiles. There is not perfect correlation with edge turbulence suppression, indicating that the turbulence decrease may be a necessary, but not sufficient, condition for the pedestal and confinement improvements. Supported by US DoE Awards DE-FC02-99ER54512 and DE-AC02-09CH11466.

  12. Quantifying Fish Backscattering using SONAR Instrument and Kirchhoff Ray Mode (KRM) Model

    Science.gov (United States)

    Manik, Henry M.

    2016-08-01

    Sonar instrument was used to study backscattering from tuna fish. Extraction of target strength, incidence angle, and frequency dependence of the backscattered signal for individual scatterer was important for biological information. For this purpose, acoustic measurement of fish backscatter was conducted in the laboratory. Characteristics and general trends of the target strength of fish with special reference to tuna fish were investigated by using a Kirchhoff Ray Mode (KRM) model. Backscattering strength were calculated for the KRM having typical morphological and physical parameters of actual fish. Those backscattering amplitudes were shown as frequency, body length, backscattering patterns, the density and sound speed dependences, and orientation dependence. These results were compared with experimentally measured target strength data and good agreement was found. Measurement and model showed the target strength from the fish are depend on the presence of swimbladder. Target Strength increase with increasing the frequency and fish length.

  13. Reflection mode X-ray absorption spectroscopy: new applications in surface science research

    Energy Technology Data Exchange (ETDEWEB)

    Luetzenkirchen-Hecht, Dirk [Institut fuer Experimentalphysik und Institut fuer Materialwissenschaften, Fachbereich C-Physik, Bergische Universitaet Wuppertal, Gaussstr. 20, D-42097 Wuppertal (Germany)]. E-mail: dirklh@uni-wuppertal.de; Frahm, Ronald [Institut fuer Experimentalphysik und Institut fuer Materialwissenschaften, Fachbereich C-Physik, Bergische Universitaet Wuppertal, Gaussstr. 20, D-42097 Wuppertal (Germany)

    2005-02-28

    Reflection mode grazing incidence X-ray absorption spectroscopy (GIXAFS) was applied for the in situ investigation of solid/liquid interfaces. Results obtained during the active dissolution of metals are presented. In the case of silver in neutral or weakly acidic Na{sub 2}SO{sub 4} solutions (pH 6.5), the formation of an Ag-O species at the surface of the Ag-electrode can be proven, i.e. the active dissolution proceeds via a non-protecting surface layer, the thickness of which was estimated to be about 5 nm. The atomic short-range order of this surface layer is different from polycrystalline silver oxides (Ag{sub 2}O and AgO) and relates to a more disordered or amorphous Ag{sup 1+} oxide.

  14. X-ray detection with a scintillating YAP-window hybrid photomultiplier tube

    CERN Document Server

    D'Ambrosio, C; Leutz, H; Puertolas, D; Rosso, E

    2000-01-01

    A YAP(YAlO/sub 3/:Ce)-scintillating window, coated on its inner surface with an S20-photocathode, seals a cross-focusing hybrid photomultiplier tube (HPMT) equipped with a small p-i-n anode of 2-mm diameter. This new radiation detector separates X-ray lines down to about 2-keV peak energy from the HPMT noise. Its detection efficiency for high gamma energies depends on the YAP-window thickness and amounts to about 18% attenuation at 400-keV energy in the present version. Competitive radiation detectors like Si photodiodes and Si drift chambers are discussed and compared to our prototype, with particular attention given to their energy resolution and noise performance, which limits their active area considerably. (19 refs).

  15. Structure of biomembrane-on-silicon hybrids derived from X-ray reflectometry

    Energy Technology Data Exchange (ETDEWEB)

    Birkholz, M. [IHP, Im Technologiepark 25, D-15236 Frankfurt (Germany)]. E-mail: birkholz@ihp-microelectronics.com; Zaumseil, P. [IHP, Im Technologiepark 25, D-15236 Frankfurt (Germany); Kittler, M. [IHP, Im Technologiepark 25, D-15236 Frankfurt (Germany); Wallat, I. [Fachbereich Physik, FU Berlin, Arnimallee 14, D-14195 Berlin (Germany); Heyn, M.P. [Fachbereich Physik, FU Berlin, Arnimallee 14, D-14195 Berlin (Germany)

    2006-10-15

    The organic-inorganic interface and its proper structural adjustment are of central importance for the fabrication of hybrid material systems from biomolecules and semiconductors. Such material hybrids are currently under development for several advanced applications, in particular for biomolecular sensing. An investigation of biomolecular immobilization on semiconductor surfaces by X-ray reflectometry (XRR) will be presented. Complete biomembrane patches of purple membrane (PM) from Halobacterium salinarum were immobilized on oxidized and nitrided silicon wafers. A covalent immobilization protocol based on 3-aminopropyltriethoxysilane (APTS) and glutaric dialdehyde (GD) was applied for cross-linking the biomolecules to the semiconductor surface. XRR could be shown to yield the relevant morphological parameters of biomolecular monolayers such as layer thickness, interface roughness and coverage. Synchrotron radiation was not required, but a laboratory rotating anode set-up was sufficient to study the prepared stacking of organic monolayers. According to the measurement and analysis of XRR patterns both cross-linking layers APTS and GD are required for bonding purple membrane patches to SiO{sub 2}/Si, whereas GD alone suffices for cross-linking to Si{sub 3}N{sub 4}/Si. This distinct behavior offers a pathway for nanopatterning of biomolecules on Si surfaces by selective passivation.

  16. CHARACTERISTICS OF DROPLET TRANSFER IN CO2 LASER-MIG HYBRID WELDING WITH SHORT-CIRCUITING MODE

    Institute of Scientific and Technical Information of China (English)

    LEI Zhenglong; CHEN Yanbin; LI Liqun; WU Lin

    2006-01-01

    LF6 aluminum alloy plates with 4.5 mm thickness are welded in this experiment. Welding is carried out by using the CO2 laser-MIG paraxial hybrid welding in flat position. The experimental results indicate that the inherent droplet transfer cycle time of conventional MIG arc is changed due to the interaction between CO2 laser beam and MIG arc in the short-circuiting mode of laser-MIG hybrid welding. Because of the preheating action of CO2 laser to electrode and base material, the droplet transfer frequency of MIG arc is increased in the hybrid welding process. When laser power is increased to a certain degree, the droplet transfer frequency is decreased due to the effect of laser-induced keyhole. Furthermore, through analyzing the MIG welding current and arc voltage waveforms and the characteristics of droplet transfer in the hybrid welding process, the effect of laser energy and the action point between laser beam and arc on the frequency of droplet transfer and weld appearance is investigated in details.

  17. A strategy to achieve efficient dual-mode luminescence in lanthanide-based magnetic hybrid nanostructure and its demonstration for the detection of latent fingerprints.

    Science.gov (United States)

    Shahi, Praveen K; Singh, Priyam; Singh, Akhilesh K; Singh, Sunil K; Rai, Shyam B; Prakash, Rajiv

    2017-04-01

    We have synthesized a novel inorganic-organic hybrid nanostructure (IOHN) composed of fluoride nanophosphor (NaGd0.78Er0.02Yb0.2F4) and β-diketones complex (Eu(DBM)3Phen). The Le Bail fitting of X-ray diffraction data suggests that the nanophoshor crystallizes in a hexagonal structure (P63/m space group). The TEM studies reveal that the nanophosphor and the IOHN both have average particle size of 6-8nm. The Eu(DBM)3Phen and NaGd0.78Er0.02Yb0.2F4 show characteristic down-shifting (DS) and up-conversion (UC) emission, under UV and NIR excitation, respectively. The IOHN comprises an excellent dual-mode optical features (DS and UC) of both the phases. Energy transfer from Er(3+) (doped in inorganic phase) to Eu(3+) (coordinated in organic phase) clearly demonstrates for a viable coupling between both the phases. IOHN material was found to be unique for the visualization of latent fingermarks. Because of ultrafine particle size the surface to volume ratio is relatively higher which improves the attachment of particles with the fingermarks. On the other hand, the strong paramagnetic property helps to remove excess material with magnetic wand easily. These properties provide an opportunity to probe even very weak fingermarks. Notwithstanding this, the dual-mode emission is useful for the visualization of latent fingermarks on multi-color surfaces as well.

  18. Mode I fracture toughness of carbon-glass/epoxy interply hybrid composites

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Ha Na; Kim, Yon Jig [Chonbuk National University, Jeonju (Korea, Republic of)

    2015-05-15

    In this study, the fracture toughness of carbon-glass fiber reinforced epoxy interply hybrid composite was investigated. In this experiment, the interply hybrid composites were manufactured using a vacuum-assisted resin transfer molding (VARTM) process. The fracture toughness of the interply hybrid composites was decreased with increasing the number of glass fabrics. The decrease in fracture toughness with an increase in the glass fiber content can be expressed in the form of a linear equation. Test results showed that the arrangement of fiber significantly influences the fracture toughness of the composite material. Glass fiber was effective against improving the fracture toughness of the hybrid composite when the glass fibers are dispersed by multi layers rather than a single layer.

  19. An alpha particle instrument with alpha, proton, and X-ray modes for planetary chemical analyses

    Science.gov (United States)

    Economou, T. E.; Turkevich, A. L.

    1976-01-01

    The interaction of alpha particles with matter is employed in a compact instrument that could provide rather complete in-situ chemical analyses of surfaces and thin atmospheres of extraterrestrial bodies. The instrument is a miniaturized and improved version of the Surveyor lunar instrument. The backscattering of alpha particles and (alpha, p) reactions provide analytical data on the light elements (carbon-iron). An X-ray mode that detects the photons produced by the alpha sources provides sensitivity and resolution for the chemical elements heavier than about silicon. The X-rays are detected by semiconductor detectors having a resolution between 150 and 250 eV at 5.9 keV. Such an instrument can identify and determine with good accuracy 99 percent of the atoms (except hydrogen) in rocks. For many trace elements, the detecting sensitivity is a few ppm. Auxiliary sources could be used to enhance the sensitivities for elements of special interest. The instrument could probably withstand the acceleration involved in semi-hard landings.

  20. Sliding Mode Controller for Three-Phase Hybrid Active Power Filter with Photovoltaic Application

    OpenAIRE

    Blorfan, Ayman; Merckle, Jean; Flieller, Damien; Wira, Patrice; Sturtzer, Guy

    2012-01-01

    International audience; This paper presents a new three-phase hybrid active power filter configuration that interconnects a passive high-pass filter in parallel with an active power filter and a photovoltaic system. The proposed configuration can improves the filtering performance of the conventional active power filter, as well as simultaneously supply the power from the photovoltaic arrays to the load and utility. This paper will describe the proposed hybrid active power filter control usin...

  1. A hybrid model for PM₂.₅ forecasting based on ensemble empirical mode decomposition and a general regression neural network.

    Science.gov (United States)

    Zhou, Qingping; Jiang, Haiyan; Wang, Jianzhou; Zhou, Jianling

    2014-10-15

    Exposure to high concentrations of fine particulate matter (PM₂.₅) can cause serious health problems because PM₂.₅ contains microscopic solid or liquid droplets that are sufficiently small to be ingested deep into human lungs. Thus, daily prediction of PM₂.₅ levels is notably important for regulatory plans that inform the public and restrict social activities in advance when harmful episodes are foreseen. A hybrid EEMD-GRNN (ensemble empirical mode decomposition-general regression neural network) model based on data preprocessing and analysis is firstly proposed in this paper for one-day-ahead prediction of PM₂.₅ concentrations. The EEMD part is utilized to decompose original PM₂.₅ data into several intrinsic mode functions (IMFs), while the GRNN part is used for the prediction of each IMF. The hybrid EEMD-GRNN model is trained using input variables obtained from principal component regression (PCR) model to remove redundancy. These input variables accurately and succinctly reflect the relationships between PM₂.₅ and both air quality and meteorological data. The model is trained with data from January 1 to November 1, 2013 and is validated with data from November 2 to November 21, 2013 in Xi'an Province, China. The experimental results show that the developed hybrid EEMD-GRNN model outperforms a single GRNN model without EEMD, a multiple linear regression (MLR) model, a PCR model, and a traditional autoregressive integrated moving average (ARIMA) model. The hybrid model with fast and accurate results can be used to develop rapid air quality warning systems.

  2. Hybrid neural network fraction integral terminal sliding mode control of an Inchworm robot manipulator

    Science.gov (United States)

    Rahmani, Mehran; Ghanbari, Ahmad; Ettefagh, Mir Mohammad

    2016-12-01

    This paper proposes a control scheme based on the fraction integral terminal sliding mode control and adaptive neural network. It deals with the system model uncertainties and the disturbances to improve the control performance of the Inchworm robot manipulator. A fraction integral terminal sliding mode control applies to the Inchworm robot manipulator to obtain the initial stability. Also, an adaptive neural network is designed to approximate the system uncertainties and unknown disturbances to reduce chattering phenomena. The weight matrix of the proposed adaptive neural network can be updated online, according to the current state error information. The stability of the proposed control method is proved by Lyapunov theory. The performance of the adaptive neural network fraction integral terminal sliding mode control is compared with three other conventional controllers such as sliding mode control, integral terminal sliding mode control and fraction integral terminal sliding mode control. Simulation results show the effectiveness of the proposed control method.

  3. Characterization of Si Hybrid CMOS Detectors for use in the Soft X-ray Band

    CERN Document Server

    Prieskorn, Zachary; Bongiorno, Stephen D; Falcone, Abraham D; Burrows, David N

    2013-01-01

    We report on the characterization of four Teledyne Imaging Systems HAWAII Hybrid Si CMOS detectors designed for X-ray detection. Three H1RG detectors were studied along with a specially configured H2RG. Read noise measurements were performed, with the lowest result being 7.1 e- RMS. Interpixel capacitive crosstalk (IPC) was measured for the three H1RGs and for the H2RG. The H1RGs had IPC upper limits of 4.0 - 5.5 % (up & down pixels) and 8.7 - 9.7 % (left & right pixels), indicating a clear asymmetry. Energy resolution is reported for two X-ray lines, 1.5 & 5.9 keV, at multiple temperatures between 150 - 210 K. The best resolution measured at 5.9 keV was 250 eV (4.2 %) at 150 K, with IPC contributing significantly to this measured energy distribution. The H2RG, with a unique configuration designed to decrease the capacitive coupling between ROIC pixels, had an IPC of 1.8 +/- 1.0 % indicating a dramatic improvement in IPC with no measurable asymmetry. We also measured dark current as a function of ...

  4. Multi-keV x-ray sources from HYBRID targets on GEKKO and OMEGA facilities

    Directory of Open Access Journals (Sweden)

    Primout M.

    2013-11-01

    Full Text Available The feasibility of efficient X-ray sources for radiography on the LMJ (Laser MégaJoule in the multi-kJ/ns range was demonstrated on the OMEGA laser facility (Univ. Rochester from 2002 to 2004 [1,2]. We significantly enhanced the conversion efficiency of titanium (4–6 keV, copper (8–10 keV and germanium (9–13 keV foils by using an optimized pre-pulse/pulse combination. Since higher X-ray energy and therefore electronic temperature need hydroconfinement, plastic cylindrical hohlraums internally coated with titanium, copper and germanium with various OMEGA beam configurations were successfully tested from 2005 to 2009 [3–5]. In addition, many shots with metal-doped aerogel (Ti, Fe, Ge were tested on OMEGA [6]. Recently we tested a new concept of “HYBRID sources” based on the combination of a thin titanium foil at the exit hole of a plastic cylinder filled with very low density SiO2 aerogel (2 and 5 mg/cc. The benefit of the underdense medium is, first, to transport the laser energy to the titanium foil after its conversion into a supersonic ionization front and, second, to prevent foil expansion and excessive kinetic energy losses by longitudinal hydroconfinement.

  5. ESO-Based Fuzzy Sliding-Mode Control for a 3-DOF Serial-Parallel Hybrid Humanoid Arm

    Directory of Open Access Journals (Sweden)

    Yueling Wang

    2014-01-01

    Full Text Available This paper presents a unique ESO-based fuzzy sliding-mode controller (FSMC-ESO for a 3-DOF serial-parallel hybrid humanoid arm (HHA for the trajectory tracking control problem. The dynamic model of the HHA is obtained by Lagrange method and is nonlinear in dynamics with inertia uncertainty and external disturbance. The FSMC-ESO is based on the combination of the sliding-mode control (SMC, extended state observer (ESO theory, and fuzzy control (FC. The SMC is insensitive to both internal parameter uncertainties and external disturbances. The motivation for using ESO is to estimate the disturbance in real-time. The fuzzy parameter self-tuning strategy is proposed to adjust the switching gain on line according to the running state of the system. The stability of the system is guaranteed in the sense of the Lyapunov stability theorem. The effectiveness and robustness of the designed FSMC-ESO are illustrated by simulations.

  6. Mode-locked Erbium-doped fiber laser generation using hybrid ZnO/GO saturable absorber

    Science.gov (United States)

    Hassan, H.; Ariannejad, M. M.; Safaei, R.; Amiri, I. S.; Ahmad, H.

    2017-06-01

    Mode-locked generation of erbium-doped fiber laser (EDFL) with hybrid zinc oxide/graphene oxide (ZnO/GO) thin film as saturable absorber (SA) is proposed and practically demonstrated. The SA shows the modulation depth of 18.69% and it has been sandwiched between the fiber ferrules. Mode-locked pulse occurred at pump power of 14.8 mW and by varying the pump power to maximum threshold 27.43 mW, the repetition rate of the pulse fixed at 19.98 MHz at 1563 nm of central wavelength. The pulse width is estimated as 0.90 ps, whereas the pulse energy is calculated as 27.0 nJ.

  7. Hybrid Short Term Wind Speed Forecasting Using Variational Mode Decomposition and a Weighted Regularized Extreme Learning Machine

    Directory of Open Access Journals (Sweden)

    Nantian Huang

    2016-11-01

    Full Text Available Accurate wind speed forecasting is a fundamental element of wind power prediction. Thus, a new hybrid wind speed forecasting model, using variational mode decomposition (VMD, the partial autocorrelation function (PACF, and weighted regularized extreme learning machine (WRELM, is proposed to improve the accuracy of wind speed forecasting. First, the historic wind speed time series is decomposed into several intrinsic mode functions (IMFs. Second, the partial correlation of each IMF sequence is analyzed using PACF to select the optimal subfeature set for particular predictors of each IMF. Then, the predictors of each IMF are constructed in order to enhance its strength using WRELM. Finally, wind speed is obtained by adding up all the predictors. The experiment, using real wind speed data, verified the effectiveness and advancement of the new approach.

  8. Simultaneous X-ray and radio observations of the radio-mode-switching pulsar PSR B1822-09

    Science.gov (United States)

    Hermsen, W.; Kuiper, L.; Hessels, J. W. T.; Mitra, D.; Rankin, J. M.; Stappers, B. W.; Wright, G. A. E.; Basu, R.; Szary, A.; van Leeuwen, J.

    2017-04-01

    We report on simultaneous X-ray and radio observations of the radio-mode-switching pulsar PSR B1822-09 with ESA's XMM-Newton and the Westerbork Synthesis Radio Telescope, Giant Metrewave Radio Telescope and Lovell radio telescopes. PSR B1822-09 switches between a radio-bright and radio-quiet mode, and we discovered a relationship between the durations of its modes and a known underlying radio-modulation time-scale within the modes. We discovered X-ray (energies 0.2-1.4 keV) pulsations with a broad sinusoidal pulse, slightly lagging the radio main pulse in phase by 0.094 ± 0.017, with an energy-dependent pulsed fraction varying from ∼0.15 at 0.3 keV to ∼0.6 at 1 keV. No evidence is found for simultaneous X-ray and radio mode switching. The total X-ray spectrum consists of a cool component (T ∼0.96 × 106 K, hotspot radius R ∼2.0 km) and a hot component (T ∼2.2 × 106 K, R ∼100 m). The hot component can be ascribed to the pulsed emission and the cool component to the unpulsed emission. The high-energy characteristics of PSR B1822-09 resemble those of middle-aged pulsars such as PSR B0656+14, PSR B1055-52 and Geminga, including an indication for pulsed high-energy gamma-ray emission in Fermi Large Area Telescope data. Explanations for the high pulsed fraction seem to require different temperatures at the two poles of this orthogonal rotator, or magnetic anisotropic beaming effects in its strong magnetic field. In our X-ray skymap, we found a harder source at only 5.1 ± 0.5 arcsec from PSR B1822-09, which might be a pulsar wind nebula.

  9. Linear benchmarks between the hybrid codes HYMAGYC and HMGC to study energetic particle driven Alfvénic modes

    Science.gov (United States)

    Fogaccia, G.; Vlad, G.; Briguglio, S.

    2016-11-01

    Resonant interaction between energetic particles (EPs), produced by fusion reactions and/or additional heating systems, and shear Alfvén modes can destabilize global Alfvénic modes enhancing the EP transport. In order to investigate the EP transport in present and next generation fusion devices, numerical simulations are recognized as a very important tool. Among the various numerical models, the hybrid MHD gyrokinetic one has shown to be a valid compromise between a sufficiently accurate wave-particle interaction description and affordable computational resource requirements. This paper presents a linear benchmark between the hybrid codes HYMAGYC and HMGC. The HYMAGYC code solves the full, linear MHD equations in general curvilinear geometry for the bulk plasma and describes the EP population by the nonlinear gyrokinetic Vlasov equation. On the other side, HMGC solves the nonlinear, reduced O≤ft(ε 03\\right) , pressureless MHD equations ({ε0} being the inverse aspect ratio) for the bulk plasma and the drift kinetic Vlasov equation for the EPs. The results of the HYMAGYC and HMGC codes have been compared both in the MHD limit and in a wide range of the EP parameter space for two test cases (one of which being the so-called TAE n  =  6 ITPA Energetic Particle Group test case), both characterized by {ε0}\\ll 1 . In the first test case (test case A), good qualitative agreement is found w.r.t. real frequencies, growth rates and spatial structures of the most unstable modes, with some quantitative differences for the growth rates. For the so-called ITPA test case (test case B), at the nominal energetic particle density value, the disagreement between the two codes is, on the contrary, also qualitative, as a different mode is found as the most unstable one.

  10. Study of heliospheric effects on galactic cosmic ray fluxes near Earth using low energy modes of the Pierre Auger Observatory

    Science.gov (United States)

    Saleh, Ahmed; Pierre Auger Collaboration

    2016-04-01

    Surface detector array (SD) of the Pierre Auger Observatory has the capability to observe variations in the flux of low energy secondary cosmic ray particles. Flux rates of low energy particles can be obtained either from particle count rates (scaler mode) or from charge distribution of the pulses (histogram mode), detected by individual water Cherenkov detectors (WCD). In scaler mode, SD is sensitive to particles that deposit energy between ~15 MeV and ~100 MeV in a WCD, while in histogram mode the deposited energy range can be extended up to ~1 GeV. These two low energy detection modes are excellent tools for monitoring modulations of the galactic cosmic ray flux, related to solar activity, such as Forbush decreases (with typical duration of several hours to weeks) and Solar cycle (with a duration of several years), as they provide fluxes of cosmic rays with different energies at the same detector. In this contribution we present an analysis of the effects of space weather and space climate on low energy mode data collected by the Pierre Auger Observatory in the period between 2006 and 2013. In particular, we focus on the long term trend of the cosmic ray flux. In addition to the standard corrections for atmospheric effects such as pressure, the analysis takes into account also the corrections for the long term evolution of the response of the surface detectors. Results show good correlation of the corrected low energy mode Auger data with neutron flux measurements by the global neutron monitoring network (NMDB).

  11. Bandwidth based methodology for designing a hybrid energy storage system for a series hybrid electric vehicle with limited all electric mode

    Science.gov (United States)

    Shahverdi, Masood

    The cost and fuel economy of hybrid electrical vehicles (HEVs) are significantly dependent on the power-train energy storage system (ESS). A series HEV with a minimal all-electric mode (AEM) permits minimizing the size and cost of the ESS. This manuscript, pursuing the minimal size tactic, introduces a bandwidth based methodology for designing an efficient ESS. First, for a mid-size reference vehicle, a parametric study is carried out over various minimal-size ESSs, both hybrid (HESS) and non-hybrid (ESS), for finding the highest fuel economy. The results show that a specific type of high power battery with 4.5 kWh capacity can be selected as the winning candidate to study for further minimization. In a second study, following the twin goals of maximizing Fuel Economy (FE) and improving consumer acceptance, a sports car class Series-HEV (SHEV) was considered as a potential application which requires even more ESS minimization. The challenge with this vehicle is to reduce the ESS size compared to 4.5 kWh, because the available space allocation is only one fourth of the allowed battery size in the mid-size study by volume. Therefore, an advanced bandwidth-based controller is developed that allows a hybridized Subaru BRZ model to be realized with a light ESS. The result allows a SHEV to be realized with 1.13 kWh ESS capacity. In a third study, the objective is to find optimum SHEV designs with minimal AEM assumption which cover the design space between the fuel economies in the mid-size car study and the sports car study. Maximizing FE while minimizing ESS cost is more aligned with customer acceptance in the current state of market. The techniques applied to manage the power flow between energy sources of the power-train significantly affect the results of this optimization. A Pareto Frontier, including ESS cost and FE, for a SHEV with limited AEM, is introduced using an advanced bandwidth-based control strategy teamed up with duty ratio control. This controller

  12. Microplasma mode transition and corresponding propagation characteristics controlled by manipulating electric field strength in a microchannel-cavity hybrid structure device

    Science.gov (United States)

    Wang, Y.; Ni, J. H.; Zhong, S.; Zhang, X.; Liang, Z.; Liu, C.; Park, S.-J.; Eden, J. G.

    2016-10-01

    Plasma redistribution in a symmetric microchannel-cavity hybrid structure device has been investigated by modulating the applied electric field strength. The device array has been operated in 200 Torr of argon, driven by a 20 kHz bipolar waveform. With the existence of the intervening microchannel between microcavities, several stable modes of operation of the microplasma have been observed, including cavity mode, hybrid mode and channel mode. Transition between the modes occurs with modulation of the applied voltage from 800 to 1100 V. The characteristics of microplasma propagation in different modes are investigated and the propagation speed along diagonal direction of the device in cavity mode, hybrid and channel mode are calculated to be ~48, ~29 and ~32 km s-1, respectively. Nonhomogeneous electric field strength distribution and plasma interaction have been discussed to explain these experimental results. Emission intensity and propagation speed differences in the cavity mode between the polarities of the applied voltage are interpreted through spatially resolved measurements of the emission profile in a partial channel-cavity array.

  13. Optimal Line Pressure Control for an Automatic Transmission-Based Parallel Hybrid Electric Vehicle considering Mode Change and Gear Shift

    Directory of Open Access Journals (Sweden)

    Minseok Song

    2014-05-01

    Full Text Available An optimal line pressure control algorithm was proposed for the fuel economy improvement of an AT-based parallel hybrid electric vehicle (HEV. By performing lever analysis at each gear step, the required line pressure was obtained considering the torque ratio of the friction elements. In addition, the required line pressure of the mode clutch was calculated. Based on these results, the optimal line pressure map at each gear step of the EV and HEV modes was presented. Using the line pressure map, an optimal line pressure was performed for the AT input torque and mode. To investigate the proposed line pressure control algorithm, a HEV performance simulator was developed based on the powertrain model of the target HEV, and fuel economy improvement was evaluated. Simulation results showed that as the gear step became higher, the optimal line pressure control could reduce the hydraulic power loss, which gave a 2.2% fuel economy improvement compared to the existing line pressure control for the FTP-72 mode.

  14. Excitation of a nonradial mode in a millisecond X-ray pulsar XTE J1751-305

    CERN Document Server

    Lee, Umin

    2014-01-01

    We discuss candidates for non-radial modes excited in a mass accreting and rapidly rotating neutron star to explain the coherent frequency identified in the light curves of a millisecond X-ray pulsar XTE J1751-305. The spin frequency of the pulsar is $\

  15. A Hybrid Forecasting Model Based on Empirical Mode Decomposition and the Cuckoo Search Algorithm: A Case Study for Power Load

    Directory of Open Access Journals (Sweden)

    Jiani Heng

    2016-01-01

    Full Text Available Power load forecasting always plays a considerable role in the management of a power system, as accurate forecasting provides a guarantee for the daily operation of the power grid. It has been widely demonstrated in forecasting that hybrid forecasts can improve forecast performance compared with individual forecasts. In this paper, a hybrid forecasting approach, comprising Empirical Mode Decomposition, CSA (Cuckoo Search Algorithm, and WNN (Wavelet Neural Network, is proposed. This approach constructs a more valid forecasting structure and more stable results than traditional ANN (Artificial Neural Network models such as BPNN (Back Propagation Neural Network, GABPNN (Back Propagation Neural Network Optimized by Genetic Algorithm, and WNN. To evaluate the forecasting performance of the proposed model, a half-hourly power load in New South Wales of Australia is used as a case study in this paper. The experimental results demonstrate that the proposed hybrid model is not only simple but also able to satisfactorily approximate the actual power load and can be an effective tool in planning and dispatch for smart grids.

  16. Hybrid Ytterbium-doped large-mode-area photonic crystal fiber amplifier for long wavelengths

    DEFF Research Database (Denmark)

    Petersen, Sidsel Rübner; Alkeskjold, Thomas T.; Poli, Federica

    2012-01-01

    A large-mode-area Ytterbium-doped photonic crystal fiber amplifier with build-in gain shaping is presented. The fiber cladding consists of a hexagonal lattice of air holes, where three rows are replaced with circular high-index inclusions. Seven missing air holes define the large-mode-area core....... Light confinement is achieved by combined index and bandgap guiding, which allows for single-mode operation and gain shaping through distributed spectral filtering of amplified spontaneous emission. The fiber properties are ideal for amplification in the long wavelength regime of the Ytterbium gain...

  17. 850-nm hybrid fiber/free-space optical communications using orbital angular momentum modes

    DEFF Research Database (Denmark)

    Jurado-Navas, Antonio; Tatarczak, Anna; Lu, Xiaofeng;

    2015-01-01

    Light beams can carry orbital angular momentum (OAM) associated to the helicity of their phasefronts. These OAM modes can be employed to encode information onto a laser beam for transmitting not only in a fiber link but also in a free-space optical (FSO) one. Regarding this latter scenario, FSO...... modes can be seen as an efficient solution to increase the capacity and the security in the link. In this paper, we discuss an experimental demonstration of a proposal for next generation FSO communication system where a light beam carrying different OAM modes and affected by M turbulence is coupled...

  18. Design of up/down counter based on dual mode logic and Low power Hybrid dual mode dynamic flip-flop

    Directory of Open Access Journals (Sweden)

    Sandhya Venugopal

    2014-09-01

    Full Text Available This paper introduces a 4-b Johnson up-down counter that incorporates low power dual dynamic node pulsed hybrid flip-flop (DDFF with clock gating technology and a dual mode logic (DML in the counter. Clock gating disable the clock signal when the input data does not change the stored data. A DML mode logic is introduced here which improves the speed performance of the design, also achieving significant energy consumption reduction. The large capacitance in precharge node is eliminated by the DDFF and DDFF-ELM designs by following a split dynamic node structure. The DDFF offers power reduction. The DDFF-ELM reduces pipeline overhead. 4-b Johnson up-down counter is used to magnify the performance improvement of the designs, to which the DML logic is introduced. An area, power, and speed efficient method is presented here that incorporates complex logic functions into the flip-flop. The DML logic used in DDFF-ELM helps to achieve low power and high speed requirements. The simulation results are compared using T-Spice

  19. Coherent Atom-Phonon Interaction through Mode Field Coupling in Hybrid Optomechanical Systems

    CERN Document Server

    Cotrufo, Michele; Verhagen, Ewold

    2016-01-01

    We propose a novel type of optomechanical coupling which enables a tripartite interaction between a quantum emitter, an optical mode and a macroscopic mechanical oscillator. The interaction uses a mechanism we term mode field coupling: mechanical displacement modifies the spatial distribution of the optical mode field, which in turn modulates the atom-photon coupling rate. In properly designed multimode optomechanical systems, we can achieve situations in which mode field coupling is the only possible interaction pathway for the system. This enables, for example, swapping of a single excitation between emitter and phonon, creation of nonclassical states of motion and mechanical ground-state cooling in the bad-cavity regime. Importantly, the emitter-phonon coupling rate can be enhanced through an optical drive field, allowing active control of strong atom-phonon coupling for realistic experimental parameters.

  20. Dynamic Tuning and Memory Switching of Defect Modes in a Hybrid Photonic Structure

    Directory of Open Access Journals (Sweden)

    Hsiao-Tsung Wang

    2016-10-01

    Full Text Available We propose a memorable and electrically tunable photonic device by infiltrating a dual-mode chiral-doped dual-frequency liquid crystal (LC as the central defect layer in a one-dimensional photonic crystal (PC. According to the transmission properties of this structure, the wavelength tunability of defect modes is obtained by manipulating the LC layer in the dynamic mode due to the electrically controlled birefringence effect. Moreover, the switching between two memorable states, the splay and π-twist states, creates two distinct sets of defect modes at null voltage. The spectral characteristics of this device ensure its potential application as an energy-efficient multichannel wavelength filter.

  1. Hybrid mode-locked ultrashort-pulse erbium-doped fiber laser

    Science.gov (United States)

    Lazarev, Vladimir A.; Sazonkin, Stanislav S.; Pniov, Alexey B.; Tsapenko, Konstantin P.; Krylov, Alexander A.; Obraztsova, Elena D.

    2014-03-01

    One of the implementations of fs-laser with CNT-film for mode-locking is considered. Scheme of single-pulse, self-starting, stable mode-locked laser generation by appropriate polarization controllers adjustment is suggested. The mechanism of cavity length stabilization for a femtosecond fiber laser based on the pump source modulation is considered. Bandwidth of the feedback frequency stabilization system based on pump source modulation method is defined.

  2. Lower hybrid heating associated with mode conversion on the Wisconsin octupole

    Energy Technology Data Exchange (ETDEWEB)

    Owens, T.L.

    1979-08-01

    This thesis addresses the following key issues in the lower hybrid frequency range: 1. What are the importent physics aspects of wave propagation and heating in an experimental situation. 2. How effective is plasma heating in the complex magnetic field configuration of the octupole. Experimental work is accomplished by launching 1-10ms pulses of up to 40kW of radio frequency power at 140MHz corresponding to the hot plasma lower hybrid resonance in the octupole. A diploe antenna which is moveable radially and is also rotatable couples wave power to the plasma. Coupling efficiencies greater than 95% are achieved by proper antenna placement near the edge of the plasma radial density profile.

  3. Implementation of Design Failure Modes and Effects Analysis for Hybrid Vehicle Systems

    OpenAIRE

    2016-01-01

    An increase emphasis has been placed on the automotive industry to develop advanced technology vehicles which meet increasing strict government regulations and standards for emissions and fuel economy while maintaining the safety, performance, and consumer appeal of the vehicle. In response to these requirements, hybrid and electric vehicle technologies have become more complex as the necessity for vehicles with an overall better environmental impact. Modern engineers must understand the cur...

  4. Neutron and X-Ray Scattering Studies of Hybrid Perovskites for Photovoltaic Applications

    Science.gov (United States)

    Crawford, Michael; Whitfield, Pamela; Jalarvo, Niina; Ehlers, Georg; Tyagi, Madhusudan; Herron, Norman; Johnson, Lynda; Guise, William; Milas, Ivan; Cheng, Yongqiang; Daemen, Luke; Ramirez-Cuesta, Anibal; Page, Katharine; Wang, Xiaoping; Ye, Feng

    Hybrid perovskites (ABX3) have attracted a great deal of attention recently as light absorbers for photovoltaics. In these materials the A site is occupied by organic cations, for example methyl ammonium (MA) or formamidinium (FA) cations, the B site is occupied by metals, for example Pb or Sn, and the X anions are halogens (I, Br, or Cl). Typical of perovskites, these materials exhibit a series of structural phase transitions involving rotations or tilts of the BX6 octahedra, but with the added complexity that the inorganic framework is coupled to order-disorder transitions of the organic cations. We have used neutron scattering techniques to characterize the structures and dynamics of several of these compounds as a function of temperature. In addition, high resolution synchrotron x-ray diffraction measurements have been performed to investigate the structural phase transitions. These studies yield a detailed picture of the structures, dynamics, and structural phase transitions of these compounds, and provide a firm basis for understanding their excellent photovoltaic properties.

  5. The Speedster-EXD- A New Event-Driven Hybrid CMOS X-ray Detector

    Science.gov (United States)

    Griffith, Christopher V.; Falcone, Abraham D.; Prieskorn, Zachary R.; Burrows, David N.

    2016-01-01

    The Speedster-EXD is a new 64×64 pixel, 40-μm pixel pitch, 100-μm depletion depth hybrid CMOS x-ray detector with the capability of reading out only those pixels containing event charge, thus enabling fast effective frame rates. A global charge threshold can be specified, and pixels containing charge above this threshold are flagged and read out. The Speedster detector has also been designed with other advanced in-pixel features to improve performance, including a low-noise, high-gain capacitive transimpedance amplifier that eliminates interpixel capacitance crosstalk (IPC), and in-pixel correlated double sampling subtraction to reduce reset noise. We measure the best energy resolution on the Speedster-EXD detector to be 206 eV (3.5%) at 5.89 keV and 172 eV (10.0%) at 1.49 keV. The average IPC to the four adjacent pixels is measured to be 0.25%±0.2% (i.e., consistent with zero). The pixel-to-pixel gain variation is measured to be 0.80%±0.03%, and a Monte Carlo simulation is applied to better characterize the contributions to the energy resolution.

  6. The Speedster-EXD- A New Event-Driven Hybrid CMOS X-ray Detector

    CERN Document Server

    Griffith, Christopher V; Prieskorn, Zachary R; Burrows, David N

    2016-01-01

    The Speedster-EXD is a new 64x64 pixel, 40 $\\mu$m pixel pitch, 100 $\\mu$m depletion depth hybrid CMOS X-ray detector (HCD) with the capability of reading out only those pixels containing event charge, thus enabling fast effective frame rates. A global charge threshold can be specified, and pixels containing charge above this threshold are flagged and read out. The Speedster detector has also been designed with other advanced in-pixel features to improve performance, including a low-noise, high-gain CTIA amplifier that eliminates interpixel capacitance crosstalk (IPC), and in-pixel Correlated Double Sampling (CDS) subtraction to reduce reset noise. We measure the best energy resolution on the Speedster-EXD detector to be 206 eV (3.5 %) at 5.89 keV and 172 eV (10.0 %) at 1.49 keV. The average IPC to the four adjacent pixels is measured to be 0.25 $\\pm$ 0.2 % (i.e. consistent with zero). The pixel-to-pixel gain variation is measured to be 0.80 $\\pm$ 0.03 %, and a Monte Carlo simulation is applied to better chara...

  7. First Data with the Hybrid Array of Gamma-Ray Detectors (HAGRiD)

    Science.gov (United States)

    Smith, Karl; Burcher, S.; Carter, A. B.; Gryzwacz, R.; Jones, K. L.; Munoz, S.; Paulauskas, S. V.; Schmitt, K.; Thornsberry, C.; Chipps, K. A.; Febbraro, M.; Pain, S. D.; Baugher, T.; Cizewski, J. A.; Ratkiewicz, A.; Toomey, B.

    2016-09-01

    The structure of nuclei provides insight into astrophysical reaction rates that are difficult to measure directly. These studies are often performed with transfer reaction and beta-decay measurements. These experiments benefit from particle-gamma coincident measurements providing information beyond that of particle detection alone. The Hybrid Array of Gamma Ray Detectors (HAGRiD) of LaBr3(Ce) scintillators has been designed with this purpose in mind. The design of the array permits it to be coupled with particle detector systems, such as the Oak Ridge Rutgers University Barrel Array (ORRUBA) of silicon detectors and the Versatile Array of Neutron Detectors at Low Energy (VANDLE). It is also designed to operate with the Jet Experiments in Nuclear Structure and Astrophysics (JENSA) advanced target system. HAGRiD's design avoids compromising the charged-particle angular resolution due to compact geometries often used to increase the gamma efficiency in other systems. First experimental data with HAGRiD coupled to VANDLE as well as ORRUBA and JENSA will be presented. This work is supported in part by the U.S. Department of Energy, Office of Science Nuclear Physics and the National Science Foundation.

  8. Efficient dual mode multicolor luminescence in a lanthanide doped hybrid nanostructure: a multifunctional material.

    Science.gov (United States)

    Singh, S K; Singh, A K; Rai, S B

    2011-07-08

    The present work deals with inorganic-organic hybrid nanostructures capable of producing intense visible emission via upconversion (UC), downconversion (DC), and energy transfer (ET) processes which show the potential of the material as a luminescent solar collector (LSC), particularly to improve the efficiency of silicon solar cells. To achieve this, Gd2O3:Yb3+/Er3+ phosphor (average particle size∼35 nm) and a Eu(DBM)3Phen organic complex have been synthesized separately and then the hybrid structure has been developed using a simple mixing procedure. Intense UC emission (in the red, green, and blue regions) due to Er3+ is observed on near infrared (976 nm) excitation which shows color tunability with input pump power. In contrast, intense red emission of Eu3+ is observed on ultaviolet (UV) (355 nm) excitation. The feasibility of energy transfer from Er3+ ions to Eu3+ ions has also been noted. These excellent optical properties are retained even if the particles of the hybrid nanostructure are dispersed in liquid medium, which also makes it suitable for security ink purposes.

  9. Hybrid recoil mass analyzer at IUAC – First results using gas-filled mode and future plans

    Indian Academy of Sciences (India)

    N Madhavan; S Nath; T Varughese; J Gehlot; A Jhingan; P Sugathan; A K Sinha; R Singh; K M Varier; M C Radhakrishna; E Prasad; S Kalkal; G Mohanto; J J Das; Rakesh Kumar; R P Singh; S Muralithar; R K Bhowmik; A Roy; Rajesh Kumar; S K Suman; A Mandal; T S Datta; J Chacko; A Choudhury; U G Naik; A J Malyadri; M Archunan; J Zacharias; S Rao; Mukesh Kumar; P Barua; E T Subramanian; K Rani; B P Ajith Kumar; K S Golda

    2010-08-01

    Hybrid recoil mass analyzer (HYRA) is a unique, dual-mode spectrometer designed to carry out nuclear reaction and structure studies in heavy and medium-mass nuclei using gas-filled and vacuum modes, respectively and has the potential to address newer domains in nuclear physics accessible using high energy, heavy-ion beams from superconducting LINAC accelerator (being commissioned) and ECR-based high current injector system (planned) at IUAC. The first stage of HYRA is operational and initial experiments have been carried out using gas-filled mode for the detection of heavy evaporation residues and heavy quasielastic recoils in the direction of primary beam. Excellent primary beam rejection and transmission efficiency (comparable with other gas-filled separators) have been achieved using a smaller focal plane detection system. There are plans to couple HYRA to other detector arrays such as Indian national gamma array (INGA) and 4 spin spectrometer for ER tagged spectroscopic/spin distribution studies and for focal plane decay measurements.

  10. Hybrid UWB and WiMAX radio-over-multi-mode fibre for in-building optical networks

    Science.gov (United States)

    Perez, J.; Llorente, R.

    2014-01-01

    In this paper the use of hybrid WiMedia-defined ultra-wideband (UWB) and IEEE 802.16d WiMAX radio-over-fibre is proposed and experimentally demonstrated for multi-mode based in-building optical networks with the advantage of great immunity to optical transmission impairments. In the proposed approach, spectral coexistence of both signals must be achieved with negligible mutual interference. The experimental study performed addressed an indoor configuration with 50 μm multi-mode fibres (MMF) and 850 nm vertical-cavity surface-emitting laser (VCSEL) transmitters. The results indicate that the impact of the wireless convergence in radio-over-multi-mode fibre (RoMMF) is significant for UWB transmissions, mainly due to MMF dispersion and electrooptical (EO) devices with limited bandwidth. On the other hand, WiMAX transmission is feasible for a 300 m MMF and 30 m wireless link in the presence of UWB, with -31 dBm WiMAX EVM.

  11. hybridMANTIS: a CPU-GPU Monte Carlo method for modeling indirect x-ray detectors with columnar scintillators.

    Science.gov (United States)

    Sharma, Diksha; Badal, Andreu; Badano, Aldo

    2012-04-21

    The computational modeling of medical imaging systems often requires obtaining a large number of simulated images with low statistical uncertainty which translates into prohibitive computing times. We describe a novel hybrid approach for Monte Carlo simulations that maximizes utilization of CPUs and GPUs in modern workstations. We apply the method to the modeling of indirect x-ray detectors using a new and improved version of the code MANTIS, an open source software tool used for the Monte Carlo simulations of indirect x-ray imagers. We first describe a GPU implementation of the physics and geometry models in fastDETECT2 (the optical transport model) and a serial CPU version of the same code. We discuss its new features like on-the-fly column geometry and columnar crosstalk in relation to the MANTIS code, and point out areas where our model provides more flexibility for the modeling of realistic columnar structures in large area detectors. Second, we modify PENELOPE (the open source software package that handles the x-ray and electron transport in MANTIS) to allow direct output of location and energy deposited during x-ray and electron interactions occurring within the scintillator. This information is then handled by optical transport routines in fastDETECT2. A load balancer dynamically allocates optical transport showers to the GPU and CPU computing cores. Our hybridMANTIS approach achieves a significant speed-up factor of 627 when compared to MANTIS and of 35 when compared to the same code running only in a CPU instead of a GPU. Using hybridMANTIS, we successfully hide hours of optical transport time by running it in parallel with the x-ray and electron transport, thus shifting the computational bottleneck from optical tox-ray transport. The new code requires much less memory than MANTIS and, asa result, allows us to efficiently simulate large area detectors.

  12. A study of quasi-mode parametric excitations in lower-hybrid heating of tokamak plasmas

    Science.gov (United States)

    Villalon, E.; Bers, A.

    1980-03-01

    A detailed linear and non-linear analysis of quasi-mode parametric excitations, relevant to experiments in supplementary heating of tokamak plasmas, is presented. The linear analysis includes the full ion-cyclotron harmonic quasi-mode spectrum, while the nonlinear one, considering depletion of the pump electric field, is applied to the recent Alcator A heating experiment. The quasi-mode excitations are studied independently for the plasma edge and the main bulk of the plasma, and for the two typical regimes in overall density. It is concluded that the excited spectrum has a frequency close to the initial pump frequency, while the wave-number spectrum may be different from the initial linear spectrum.

  13. Energy transmission modes based on Tabu search and particle swarm hybrid optimization algorithm

    Institute of Scientific and Technical Information of China (English)

    LI xiang; CUI Ji-feng; QI Jian-xun; YANG Shang-dong

    2007-01-01

    In China, economic centers are far from energy storage bases, so it is significant to select a proper energy transferring mode to improve the efficiency of energy usage, To solve this problem, an optimal allocation model based on energy transfer mode was proposed after objective function for optimizing energy using efficiency Was established, and then, a new Tabu search and power transmission was gained.Based on the above discussion, some proposals were put forward for optimal allocation of energy transfer modes in China. By comparing other three traditional methodsthat are based on regional price differences. freight rates and annual cost witll the proposed method, the result indicates that the economic efficiency of the energy transfer Can be enhanced by 3.14%, 5.78% and 6.01%, respectively.

  14. X-ray Hybrid CMOS Detectors : Recent progress in development and characterization

    Science.gov (United States)

    Chattopadhyay, Tanmoy; Falcone, Abraham; Burrows, David N.

    2017-08-01

    PennState high energy astronomy laboratory has been working on the development and characterization of Hybrid CMOS Detectors (HCDs) for last few years in collaboration with Teledyne Imaging Sensors (TIS). HCDs are preferred over X-ray CCDs due to their higher and flexible read out rate, radiation hardness and low power which make them more suitable for next generation large area X-ray telescopic missions. An H2RG detector with 36 micron pixel pitch and 18 micron ROIC, has been selected for a sounding rocket flight in 2018. The H2RG detector provides ~2.5 % energy resolution at 5.9 keV and ~7 e- read noise when coupled to a cryo-SIDECAR. We could also detect a clear Oxygen line (~0.5 keV) from the detector implying a lower energy threshold of ~0.3 keV. Further improvement in the energy resolution and read noise is currently under progress. We have been working on the characterization of small pixel HCDs (12.5 micron pixel; smallest pixel HCDs developed so far) which is important for the development of next generation high resolution X-ray spectroscopic instrument based on HCDs. Event recognition in HCDs is another exciting prospect which have been successfully shown to work with a 64 X 64 pixel prototype SPEEDSTAR-EXD which use comparators at each pixel to read out only those pixels having detectable signal, thereby providing an order of magnitude improvement in the read out rate. Currently, we are working on the development of a large area SPEEDSTAR-EXD array for the development of a full fledged instrument. HCDs due to their fast read out, can also be explored as a large FOV instrument to study GRB afterglows and variability and spectroscopic study of other astrophysical transients. In this context, we are characterizing a Lobster-HCD system at multiple energies and multiple off-axis angles for future rocket or CubeSate experiments. In this presentation, I will briefly present these new developments and experiments with HCDs and the analysis techniques.

  15. A Three-Dimensional Ray-Tracing Study of R-X Mode Waves during High Geomagnetic Activity

    Institute of Scientific and Technical Information of China (English)

    XIAO Fu-Liang; CHEN Lun-Jin; ZHENG Hui-Nan; WANG Shui; GUO Jun

    2008-01-01

    We further present a three-dimensional(3D)ray-tracing study on the propagation characteristic of the superluminous R-X mode waves during high geomagnetic activity following our recent two-dimensional results [J.Geophys.Res.112(2007)A10214].We perform numerical calculations for this mode which originates at specific altitude r=2.0RE in the souice cavity along a 70°night geomagnetic field line.We demonstrate that the ray path of the R-X mode is essentially governed by the azimuthal angle of the wave vector k.Ray paths starting with azimuthal angle 180°(or in the meridian plane)can reach the lowest latitude,but stay at relatively higher latitudes with the azimuthal anglas other than 180°(or off the meridian plane).The results further supports the previous finding that the R-X mode may be physically present in the radiation belts under appropriate conditions.

  16. The CoRoT B-type binary HD 50230: a prototypical hybrid pulsator with g-mode period and p-mode frequency spacings⋆

    Science.gov (United States)

    Degroote, P.; Aerts, C.; Michel, E.; Briquet, M.; Pápics, P. I.; Amado, P.; Mathias, P.; Poretti, E.; Rainer, M.; Lombaert, R.; Hillen, M.; Morel, T.; Auvergne, M.; Baglin, A.; Baudin, F.; Catala, C.; Samadi, R.

    2012-06-01

    Context. B-type stars are promising targets for asteroseismic modelling, since their frequency spectrum is relatively simple. Aims: We deduce and summarise observational constraints for the hybrid pulsator, HD 50230, earlier reported to have deviations from a uniform period spacing of its gravity modes. The combination of spectra and a high-quality light curve measured by the CoRoT satellite allow a combined approach to fix the position of HD 50230 in the HR diagram. Methods: To describe the observed pulsations, classical Fourier analysis was combined with short-time Fourier transformations and frequency spacing analysis techniques. Visual spectra were used to constrain the projected rotation rate of the star and the fundamental parameters of the target. In a first approximation, the combined information was used to interpret multiplets and spacings to infer the true surface rotation rate and a rough estimate of the inclination angle. Results: We identify HD 50230 as a spectroscopic binary and characterise the two components. We detect the simultaneous presence of high-order g modes and low-order p and g-modes in the CoRoT light curve, but were unable to link them to line profile variations in the spectroscopic time series. We extract the relevant information from the frequency spectrum, which can be used for seismic modelling, and explore possible interpretations of the pressure mode spectrum. The CoRoT space mission was developed and is operated by the French space agency CNES, with participation of ESA's RSSD and Science Programmes, Austria, Belgium, Brazil, Germany, and Spain. Based on observations made with the ESO telescopes at La Silla Observatory under the ESO Large Programme LP182.D-0356, and on observations made with the Mercator Telescope, operated on the island of La Palma by the Flemish Community, at the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrofísica de Canarias, and on observations obtained with the HERMES

  17. A camera for imaging hard x-rays from suprathermal electrons during lower hybrid current drive on PBX-M

    Energy Technology Data Exchange (ETDEWEB)

    von Goeler, S.; Kaita, R.; Bernabei, S.; Davis, W.; Fishman, H.; Gettelfinger, G.; Ignat, D.; Roney, P.; Stevens, J.; Stodiek, W. (Princeton Univ., NJ (United States). Plasma Physics Lab.); Jones, S.; Paoletti, F. (Massachusetts Inst. of Tech., Cambridge, MA (United States). Plasma Fusion Center); Petravich, G. (Hungarian Academy of Sciences, Budapest (Hungary). Central Research Inst. for Physics); Rimini,

    1993-05-01

    During lower hybrid current drive (LHCD), suprathermal electrons are generated that emit hard X-ray bremsstrahlung. A pinhole camera has been installed on the PBX-M tokamak that records 128 [times] 128 pixel images of the bremsstrahlung with a 3 ms time resolution. This camera has identified hollow radiation profiles on PBX-M, indicating off-axis current drive. The detector is a 9in. dia. intensifier. A detailed account of the construction of the Hard X-ray Camera, its operation, and its performance is given.

  18. Energy Spectrum of Ultra-High Energy Cosmic Rays Observed with the Telescope Array Using a Hybrid Technique

    CERN Document Server

    Abu-Zayyad, T; Allen, M; Anderson, R; Azuma, R; Barcikowski, E; Belz, J W; Bergman, D R; Blake, S A; Cady, R; Cheon, B G; Chiba, J; Chikawa, M; Cho, E J; Cho, W R; Fujii, H; Fujii, T; Fukuda, T; Fukushima, M; Hanlon, W; Hayashi, K; Hayashi, Y; Hayashida, N; Hibino, K; Hiyama, K; Honda, K; Iguchi, T; Ikeda, D; Ikuta, K; Inoue, N; Ishii, T; Ishimori, R; Ito, H; Ivanov, D; Iwamoto, S; Jui, C C H; Kadota, K; Kakimoto, F; Kalashev, O; Kanbe, T; Kasahara, K; Kawai, H; Kawakami, S; Kawana, S; Kido, E; Kim, H B; Kim, H K; Kim, J H; Kitamoto, K; Kitamura, S; Kitamura, Y; Kobayashi, K; Kobayashi, Y; Kondo, Y; Kuramoto, K; Kuzmin, V; Kwon, Y J; Lan, J; Lim, S I; Lundquist, J P; Machida, S; Martens, K; Matsuda, T; Matsuura, T; Matsuyama, T; Matthews, J N; Minamino, M; Miyata, K; Murano, Y; Myers, I; Nagasawa, K; Nagataki, S; Nakamura, T; Nam, S W; Nonaka, T; Ogio, S; Ohnishi, M; Ohoka, H; Oki, K; Oku, D; Okuda, T; Ono, M; Oshima, A; Ozawa, S; Park, I H; Pshirkov, M S; Rodriguez, D C; Roh, S Y; Rubtsov, G; Ryu, D; Sagawa, H; Sakurai, N; Sampson, A L; Scott, L M; Shah, P D; Shibata, F; Shibata, T; Shimodaira, H; Shin, B K; Shin, J I; Shirahama, T; Smith, J D; Sokolsky, P; Springer, R W; Stokes, B T; Stratton, S R; Stroman, T; Suzuki, S; Takahashi, Y; Takeda, M; Taketa, A; Takita, M; Tameda, Y; Tanaka, H; Tanaka, K; Tanaka, M; Thomas, S B; Thomson, G B; Tinyakov, P; Tkachev, I; Tokuno, H; Tomida, T; Troitsky, S; Tsunesada, Y; Tsutsumi, K; Tsuyuguchi, Y; Uchihori, Y; Udo, S; Ukai, H; Urban, F; Vasiloff, G; Wada, Y; Wong, T; Yamakawa, Y; Yamane, R; Yamaoka, H; Yamazaki, K; Yang, J; Yoneda, Y; Yoshida, S; Yoshii, H; Zhou, X; Zollinger, R; Zundel, Z

    2013-01-01

    We measure the spectrum of cosmic rays with energies greater than $10^{18.2}$ eV with the Fluorescence Detectors (FDs) and the Surface Detectors (SDs) of the Telescope Array Experiment using the data taken in our first 2.3-year observation from May 27 2008 to September 7 2010. A hybrid air shower reconstruction technique is employed to improve accuracies in determination of arrival directions and primary energies of cosmic rays using both FD and SD data. The energy spectrum presented here is in agreement with our previously published spectra and the HiRes results.

  19. 850-nm hybrid fiber/free-space optical communications using orbital angular momentum modes.

    Science.gov (United States)

    Jurado-Navas, Antonio; Tatarczak, Anna; Lu, Xiaofeng; Olmos, Juan José Vegas; Garrido-Balsells, José María; Monroy, Idelfonso Tafur

    2015-12-28

    Light beams can carry orbital angular momentum (OAM) associated to the helicity of their phasefronts. These OAM modes can be employed to encode information onto a laser beam for transmitting not only in a fiber link but also in a free-space optical (FSO) one. Regarding this latter scenario, FSO communications are considered as an alternative and promising mean complementing the traditional optical communications in many applications where the use of fiber cable is not justified. This next generation FSO communication systems have attracted much interest recently, and the inclusion of beams carrying OAM modes can be seen as an efficient solution to increase the capacity and the security in the link. In this paper, we discuss an experimental demonstration of a proposal for next generation FSO communication system where a light beam carrying different OAM modes and affected by ℳ turbulence is coupled to the multimode fiber link. In addition, we report a better and more robust behavior of higher order OAM modes when the intermodal dispersion is dominant in the fiber after exceeding its maximum range of operation.

  20. Controlling Botrytis elliptica Leaf Blight on Hybrid Lilies through the Application of Convergent Chemical X-ray Irradiation

    Directory of Open Access Journals (Sweden)

    Sung-Jun Hong

    2016-04-01

    Full Text Available X-ray irradiation with convergent chemicals such as nano-silver particles or sodium dichloroisocyanurate (NaDCC has been used to control leaf blight on cut lilies. The oriental hybrid lily cultivars Siberia, Le Reve, and Sorbonne were irradiated five times by 200 Gy of X-rays in 2014. In 2015, Siberia and Sorbonne were irradiated three times by 150 Gy of X-rays. After artificial infection with Botrytis elliptica on the leaves and petals of cut lilies, this study used convergent chemical X-ray irradiation of 200 Gy or 150 Gy. Leaf and petal blight was measured in terms of incidence and severity at 8 days after infection using total 552 cuttings. Results indicate that the treatments of X-ray irradiation and NaDCC in 2014 and 2015 slightly decreased the severity of petal blight on Siberia and Sorbonne. However, the results were not significant and severity did not decrease as NaDCC concentration increased. Vase-life was observed separately after X-ray irradiation of 270 cut lilies in 2014 and 108 cut lilies in 2015. Chlorophyll content was not affected by either 200 Gy or 150 Gy of X-rays. The number of days of fully opened flowers at Siberia of 150 Gy and Le Revu of 200 Gy increased by 1–2 days. In addition, the relative fresh weights of the X-rayed flowers were 10% drier than the non-irradiated controls. Overall, leaf blight control by X-ray was inferior to the control by gamma rays, and petal color was bleached in Sorbonne and Le Reve cvs. by 150 Gy of X-rays.

  1. Hybrid Fuzzy Sliding Mode Control of a DFIG Integrated into the Network

    Directory of Open Access Journals (Sweden)

    Belabbas Belkacem

    2013-12-01

    Full Text Available This paper presents the study of a variable speed wind energy conversion system using a Doubly Fed Induction Generator (DFIG based on a Fuzzy sliding mode control (FSMC applied to achieve control of active and reactive powers exchanged between the stator of the DFIG and the grid to ensure a Maximum Power Point Tracking (MPPT of a wind energy conversion system. However the principal drawback of the sliding mode, is the chattering effect which characterized by torque ripple, this phenomena is undesirable and harmful for the machines, it generates noises and additional forces of torsion on the machine shaft. In order to reduce the chattering effect, the Sign function of sliding mode controller’s discontinuous part is replaced by a fuzzy logic; we will have the fuzzy sliding mode controller (FSMC. The FSMC makes it possible to combine the performances of the two types of controllers (SMC and FLC and eliminates the chattering effect. The proposed control algorithm is applied to a DFIG where the stator is directly connected to the grid and the rotor is connected to a three-level converter structure NPC to suppress low level harmonics, higher frequencies will be filtered out by the machine. Second goal of this paper is to extract a maximum of power; the rotor side converter is controlled by using a stator flux-oriented strategy. The decoupling created by the control between active and reactive stator power allows keeping the power factor close to unity. Simulation results show that the wind turbine can operate at its optimum energy for a wide range of wind speed. Both simulation and validation results show effectiveness of the proposed control strategy is in terms of power regulation. Moreover, the fuzzy sliding mode approach is arranged so as to reduce the chattering produced in the generated power that could lead to increased mechanical stress because of strong torque variations.

  2. A novel camera type for very high energy gamma-ray astronomy based on Geiger-mode avalanche photodiodes

    CERN Document Server

    Anderhub, H; Biland, A; Boller, A; Braun, I; Bretz, T; Commichau, S; Commichau, V; Dorner, D; Gendotti, A; Grimm, O; von Gunten, H; Hildebrand, D; Horisberger, U; Krähenbühl, T; Kranich, D; Lorenz, E; Lustermann, W; Mannheim, K; Neise, D; Pauss, F; Renker, D; Rhode, W; Rissi, M; Röser, U; Rollke, S; Stark, L S; Stucki, J -P; Viertel, G; Vogler, P; Weitzel, Q

    2009-01-01

    Geiger-mode avalanche photodiodes (G-APD) are promising new sensors for light detection in atmospheric Cherenkov telescopes. In this paper, the design and commissioning of a 36-pixel G-APD prototype camera is presented. The data acquisition is based on the Domino Ring Sampling (DRS2) chip. A sub-nanosecond time resolution has been achieved. Cosmic-ray induced air showers have been recorded using an imaging mirror setup, in a self-triggered mode. This is the first time that such measurements have been carried out with a complete G-APD camera.

  3. A novel camera type for very high energy gamma-ray astronomy based on Geiger-mode avalanche photodiodes

    Energy Technology Data Exchange (ETDEWEB)

    Anderhub, H; Biland, A; Boller, A; Braun, I; Commichau, S; Commichau, V; Dorner, D; Gendotti, A; Grimm, O; Gunten, H von; Hildebrand, D; Horisberger, U; Kraehenbuehl, T; Kranich, D; Lorenz, E; Lustermann, W [Institute for Particle Physics, ETH Zurich, Schafmattstr. 20, 8093 Zurich (Switzerland); Backes, M; Neise, D [TU Dortmund University, Otto-Hahn-Str. 4, 44227 Dortmund (Germany); Bretz, T; Mannheim, K [University of Wuerzburg Am Hubland, 97074 Wuerzburg (Germany)], E-mail: qweitzel@phys.ethz.ch (and others)

    2009-10-15

    Geiger-mode avalanche photodiodes (G-APD) are promising new sensors for light detection in atmospheric Cherenkov telescopes. In this paper, the design and commissioning of a 36-pixel G-APD prototype camera is presented. The data acquisition is based on the Domino Ring Sampling (DRS2) chip. A sub-nanosecond time resolution has been achieved. Cosmic-ray induced air showers have been recorded using an imaging mirror setup, in a self-triggered mode. This is the first time that such measurements have been carried out with a complete G-APD camera.

  4. X-ray thermal-diffuse-scattering study of soft modes in paraelectric BaTiO[sub 3

    Energy Technology Data Exchange (ETDEWEB)

    Takesue, N. (Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801 (United States)); Maglione, M. (Laboratoire de Physique, Universite de Bourgogne, Batiment Mirande, B. P. 138, 21004 Dijon Cedex (France)); Chen, H. (Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801 (United States))

    1995-03-01

    Anomalous x-ray thermal diffuse scattering (TDS) from the paraelectric BaTiO[sub 3] has been measured as a function of temperature using synchrotron radiation. Sheets of intensities that were previously reported have been confirmed. The origin of the observed TDS intensities is attributed to the soft on-(100) TA modes and overdamped [010][sub TO] mode for reduced wave vector [ital q][gt]0.25 and [lt]0.25, respectively. In agreement with the previous neutron inelastic scattering experiment, our results support the notion of the one-dimensionally correlated optic motion of atoms.

  5. State Estimation of a Class of Hybrid Systems in the Presence of Unknown Mode Transitions%模式转换未知的一类混杂系统的状态估计

    Institute of Scientific and Technical Information of China (English)

    王文辉; 彭昭; 周东华

    2005-01-01

    Since the state of hybrid systems is determined by interacting continuous and discrete dynamics, the state estimation of hybrid systems becomes a challenging problem. It is more complicated when the discrete mode transition information is not available, and the modes of hybrid systems are nonlinear stochastic dynamic systems. To address this problem, this paper proposes a novel hybrid strong tracking filter (HSTF) for state estimation of a class of hybrid nonlinear stochastic systems with unknown mode transition, the method for designing HSTF is presented. The HSTF can estimate the continuous state and discrete mode accurately with unknown mode transition information, and the estimation of hybrid states is robust against the initial state. Simulation results illustrate the effectiveness of the proposed approach.

  6. A Hybrid Scheme Motion Controller by Sliding Mode and Two-Degree-of-Freedom Controls to Minimize the Chattering

    Directory of Open Access Journals (Sweden)

    Chiu-Keng Lai

    2014-01-01

    Full Text Available Sliding mode control (SMC is rapped for the chattering due to high gain control. However, high gain control causes the system robust. For developing a system with robustness of SMC, a servo motor motion controller combining the two-degree-of-freedom (2DOF system and SMC is proposed. The discussed motion type is point-to-point control with the constraint of trapezoid velocity profile. SMC is designed to guide the motor motion to follow a predefined trail, and the inner 2DOF system is used to compensate the deterioration due to the adoption of load observer. The proposed hybrid system is realized on a PC-based motion controller, and the validness is verified by simulation and experimental results.

  7. Upper Bounds on r-Mode Amplitudes from Observations of Low-Mass X-Ray Binary Neutron Stars

    Science.gov (United States)

    Mahmoodifar, Simin; Strohmayer, Tod

    2013-01-01

    We present upper limits on the amplitude of r-mode oscillations and gravitational-radiation-induced spin-down rates in low-mass X-ray binary neutron stars, under the assumption that the quiescent neutron star luminosity is powered by dissipation from a steady-state r-mode. For masses <2M solar mass we find dimensionless r-mode amplitudes in the range from about 1×10(exp-8) to 1.5×10(exp-6). For the accreting millisecond X-ray pulsar sources with known quiescent spin-down rates, these limits suggest that approx. less than 1% of the observed rate can be due to an unstable r-mode. Interestingly, the source with the highest amplitude limit, NGC 6440, could have an r-mode spin-down rate comparable to the observed, quiescent rate for SAX J1808-3658. Thus, quiescent spin-down measurements for this source would be particularly interesting. For all sources considered here, our amplitude limits suggest that gravitational wave signals are likely too weak for detection with Advanced LIGO. Our highest mass model (2.21M solar mass) can support enhanced, direct Urca neutrino emission in the core and thus can have higher r-mode amplitudes. Indeed, the inferred r-mode spin-down rates at these higher amplitudes are inconsistent with the observed spin-down rates for some of the sources, such as IGR J00291+5934 and XTE J1751-305. In the absence of other significant sources of internal heat, these results could be used to place an upper limit on the masses of these sources if they were made of hadronic matter, or alternatively it could be used to probe the existence of exotic matter in them if their masses were known.

  8. A Hybrid Model Based on Ensemble Empirical Mode Decomposition and Fruit Fly Optimization Algorithm for Wind Speed Forecasting

    Directory of Open Access Journals (Sweden)

    Zongxi Qu

    2016-01-01

    Full Text Available As a type of clean and renewable energy, the superiority of wind power has increasingly captured the world’s attention. Reliable and precise wind speed prediction is vital for wind power generation systems. Thus, a more effective and precise prediction model is essentially needed in the field of wind speed forecasting. Most previous forecasting models could adapt to various wind speed series data; however, these models ignored the importance of the data preprocessing and model parameter optimization. In view of its importance, a novel hybrid ensemble learning paradigm is proposed. In this model, the original wind speed data is firstly divided into a finite set of signal components by ensemble empirical mode decomposition, and then each signal is predicted by several artificial intelligence models with optimized parameters by using the fruit fly optimization algorithm and the final prediction values were obtained by reconstructing the refined series. To estimate the forecasting ability of the proposed model, 15 min wind speed data for wind farms in the coastal areas of China was performed to forecast as a case study. The empirical results show that the proposed hybrid model is superior to some existing traditional forecasting models regarding forecast performance.

  9. The CoRoT B-type binary HD50230: a prototypical hybrid pulsator with g-mode period and p-mode frequency spacings

    CERN Document Server

    Degroote, P; Michel, E; Briquet, M; Pápics, P I; Amado, P; Mathias, P; Poretti, E; Rainer, M; Lombaert, R; Hillen, M; Morel, T; Auvergne, M; Baglin, A; Baudin, F; Catala, C; Samadi, R

    2012-01-01

    B-type stars are promising targets for asteroseismic modelling, since their frequency spectrum is relatively simple. We deduce and summarise observational constraints for the hybrid pulsator, HD50230, earlier reported to have deviations from a uniform period spacing of its gravity modes. The combination of spectra and a high-quality light curve measured by the CoRoT satellite allow a combined approach to fix the position of HD50230 in the HR diagram. To describe the observed pulsations, classical Fourier analysis was combined with short-time Fourier transformations and frequency spacing analysis techniques. Visual spectra were used to constrain the projected rotation rate of the star and the fundamental parameters of the target. In a first approximation, the combined information was used to interpret multiplets and spacings to infer the true surface rotation rate and a rough estimate of the inclination angle. We identify HD50230 as a spectroscopic binary and characterise the two components. We detect the simu...

  10. Investigate the Performance of LG 00 Mode in Cost Effective Hybrid Radio over Multimode Transmission System

    Directory of Open Access Journals (Sweden)

    Pardeep Kaur

    2014-05-01

    Full Text Available Radio over fiber (RoF technology composed for apprehension of future high performance integrated networks and future broadband networks. Multimode fiber links can offer a convenient approach for low cost and short Radio over Fiber (RoF systems. This work is based on the cost effective radio over multimode transmission system (Ro-MMF for long reach transmission. Error free transmission of 10 Gbps data with 10 GHz radio signal over multimode fiber link successfully demonstrated over 40 km. furthermore, The results are represented for Ro-MMF system by using LG (Laguerre-Gaussian 00 mode. The Performance of LG 00 mode in terms of SNR and Eye diagram investigated in proposed system.

  11. Qualitative: Python Tool for MT Quality Estimation Supporting Server Mode and Hybrid MT

    Directory of Open Access Journals (Sweden)

    Avramidis Eleftherios

    2016-10-01

    Full Text Available We are presenting the development contributions of the last two years to our Python opensource Quality Estimation tool, a tool that can function in both experiment-mode and online web-service mode. The latest version provides a new MT interface, which communicates with SMT and rule-based translation engines and supports on-the-fly sentence selection. Additionally, we present an improved Machine Learning interface allowing more efficient communication with several state-of-the-art toolkits. Additions also include a more informative training process, a Python re-implementation of QuEst baseline features, a new LM toolkit integration, an additional PCFG parser and alignments of syntactic nodes.

  12. A hybrid mode choice model to account for the dynamic effect of inertia over time

    DEFF Research Database (Denmark)

    Cherchi, Elisabetta; Börjesson, Maria; Bierlaire, Michel

    gathered over a continuous period of time, six weeks, to study both inertia and the influence of habits. Tendency to stick with the same alternative is measured through lagged variables that link the current choice with the previous trip made with the same purpose, mode and time of day. However, the lagged...... effect of the previous trips is not constant but it depends on the individual propensity to undertake habitual trips which is captured by the individual specific latent variable. And the frequency of the trips in the previous week is used as an indicator of the habitual behavior. The model estimation...... confirms that the tendency to stick with the same alternative varies not only among modes but also across individuals as a function of the individual propensity to undertake habitual behavior....

  13. Hybridized plasmon resonant modes in molecular metallodielectric quad-triangles nanoantenna

    Science.gov (United States)

    Ahmadivand, Arash; Sinha, Raju; Pala, Nezih

    2015-11-01

    In this study, we examined the plasmon response for both metallic and metallodielectric nanoantennas composed of four gold (Au) triangles in a quadrumer orientation. Tailoring an artificial metallic quad-triangles nanoantenna, it is shown that the structure is able to support pronounced plasmon and Fano resonances in the visible spectrum. Using plasmon transmutation effect, we showed that the plasmonic response of the proposed cluster can be enhanced with the placement of carbon nanoparticles in the offset gaps between the proximal triangles. It is verified that this structural modification gives rise to formation of new collective magnetic antibonding (dark) plasmon modes. Excitation of these subradiant dark modes leads to formation of narrower and deeper Fano resonances in the spectral response of the metallodielectric nanoantenna. To investigate the practical applications of the metallodielectric structure, we immersed the nano-assembly in various liquids with different refractive indices to define its sensitivity to the environmental perturbation as a plasmonic biological sensor.

  14. On sliding mode observer for a hybrid three-cell converter

    KAUST Repository

    Khelouat, Samir

    2013-10-01

    In this paper, we propose a sliding mode observer to estimate the capacitor voltages of the 3-cell converter. New concept recently introduced, based on geometrical condition for observability analysis is used. The convergence of estimation error based on the solution of an LMI system is shown. Finally, illustrative results are given in order to show the efficiency of the designed observer. © 2013 IEEE.

  15. Evaluation of a photon-counting hybrid pixel detector array with a synchrotron X-ray source

    Science.gov (United States)

    Ponchut, C.; Visschers, J. L.; Fornaini, A.; Graafsma, H.; Maiorino, M.; Mettivier, G.; Calvet, D.

    2002-05-01

    A photon-counting hybrid pixel detector (Medipix-1) has been characterized using a synchrotron X-ray source. The detector consists of a readout ASIC with 64×64 independent photon-counting cells of 170×170 μm 2 pitch, bump-bonded to a 300 μm thick silicon sensor, read out by a PCIbus-based electronics, and a graphical user interface (GUI) software. The intensity and the energy tunability of the X-ray source allow characterization of the detector in the time, space, and energy domains. The system can be read out on external trigger at a frame rate of 100 Hz with 3 ms exposure time per frame. The detector response is tested up to more than 7×10 5 detected events/pixel/s. The point-spread response shows beam reveals no loss in sensitivity between adjacent pixels as could result from charge sharing in the silicon sensor. Photons down to 6 keV can be detected after equalization of the thresholds of individual pixels. The obtained results demonstrate the advantages of photon-counting hybrid pixel detectors and particularly of the Medipix-1 chip for a wide range of X-ray imaging applications, including those using synchrotron X-ray beams.

  16. Fast 3d Hybrid Seismic Modeling: Ray-fd Approach For Elastic Models With Locally Complex Structures

    Science.gov (United States)

    Oprsal, I.; Brokesova, J.; Faeh, D.; Giardini, D.

    Hybrid approaches may find broad applications wherever full source, path,and site effects modeling methods are too expensive. A new efficient hybrid method allowing to compute seismic wavefield in large 3D elastic models containing a complex local structure embedded in a large, but considerably simpler, structure is designed. This hybrid method combines the ray approach in the large simple structure with the finite difference (FD) approach in the local complex structure. The hybrid method is based on two successive steps. In the 1st one, the source and path information is carried by wavefield propagating in the large simple structure. This wavefield, calculated by the ray method, is incident at the points along a two-fold formal boundary (excitation box, EB) surrounding that part of the model which is to be replaced by the complex medium in the 2nd step. 3D rays are necessary due to ar- bitrary source-EB configuration, even in case the 1st step structure is less dimensional (2D, 1D, homogeneous). Along EB, the ray endpoints may be distributed sparsely thanks to relative simplicity of the structure. This reduces computer time requirements and also the size of the excitation file saved on the disk. The ray wavefield along EB provides (after interpolation in space and time) the input for the second step consisting in calculating the complete wavefield by the 3D FD method on irregular grids. The FD computational domain contains the EB and its close vicinity. The 2nd step model differs from the 1st step model only inside the EB where the local complex structure is inserted. To verify the consistency between the 1st and the 2nd step binding, the 2nd step computation can be performed on (unchanged) 1st step model ('replication test'). This should give the same wavefield as the 1st step inside, and zero wavefield outside the EB. The EB remains fully permeable for all waves propagating within the FD domain. Provided the 1st step structure does not contain too many layers

  17. Hybrid echo and x-ray image guidance for cardiac catheterization procedures by using a robotic arm: a feasibility study

    Energy Technology Data Exchange (ETDEWEB)

    Ma Yingliang; Penney, Graeme P; Razavi, Reza; Rhode, Kawal S [Division of Imaging Sciences, King' s College, London SE1 7EH (United Kingdom); Bos, Dennis; Frissen, Peter [Philips Applied Technologies, High Tech. Campus 7, 5656 AE Eindhoven (Netherlands); Rinaldi, C Aldo, E-mail: y.ma@kcl.ac.u [Department of Cardiology, Guy' s and St Thomas' NHS Foundation Trust, London SE1 7EH (United Kingdom)

    2010-07-07

    We present a feasibility study on hybrid echocardiography (echo) and x-ray image guidance for cardiac catheterization procedures. A self-tracked, remotely operated robotic arm with haptic feedback was developed that attached to a standard x-ray table. This was used to safely manipulate a three-dimensional (3D) trans-thoracic echo probe during simultaneous x-ray fluoroscopy and echo acquisitions. By a combination of calibration and tracking of the echo and x-ray systems, it was possible to register the 3D echo images with the 2D x-ray images. Visualization of the combined data was achieved by either overlaying triangulated surfaces extracted from segmented echo data onto the x-ray images or by overlaying volume rendered 3D echo data. Furthermore, in order to overcome the limited field of view of the echo probe, it was possible to create extended field of view (EFOV) 3D echo images by co-registering multiple tracked echo data to generate larger roadmaps for procedure guidance. The registration method was validated using a cross-wire phantom and showed a 2D target registration error of 3.5 mm. The clinical feasibility of the method was demonstrated during two clinical cases for patients undergoing cardiac pacing studies. The EFOV technique was demonstrated using two healthy volunteers. (note)

  18. Hybrid confinement of optical and mechanical modes in a bullseye optomechanical resonator

    CERN Document Server

    Santos, Felipe G S; Luiz, Gustavo O; Benevides, Rodrigo S; Wiederhecker, Gustavo S; Alegre, Thiago P Mayer

    2016-01-01

    Optomechanical cavities have proven to be an exceptional tool to explore fundamental and technological aspects of the interaction between mechanical and optical waves. Such interactions strongly benefit from cavities with large optomechanical coupling, high mechanical and optical quality factors, and mechanical frequencies larger than the optical mode linewidth, the so called resolved sideband limit. Here we demonstrate a novel optomechanical cavity based on a disk with a radial mechanical bandgap. This design confines light and mechanical waves through distinct physical mechanisms which allows for independent control of the mechanical and optical properties. Our device design is not limited by unique material properties and could be easily adapted to allow large optomechanical coupling and high mechanical quality factors with other promising materials. Finally, our demonstration is based on devices fabricated on a commercial silicon photonics facility, demonstrating that our approach can be easily scalable.

  19. A hybrid mode choice model to account for the dynamic effect of inertia over time

    DEFF Research Database (Denmark)

    Cherchi, Elisabetta; Börjesson, Maria; Bierlaire, Michel

    gathered over a continuous period of time, six weeks, to study both inertia and the influence of habits. Tendency to stick with the same alternative is measured through lagged variables that link the current choice with the previous trip made with the same purpose, mode and time of day. However, the lagged......The influence of habits, giving rise to inertia effect, in the choice process has been intensely debated in the literature. Typically inertia is accounted for by letting the indirect utility functions of the alternatives of the choice situation at time t depend on the outcome of the choice made...... at a previous point in time. However, according to the psychological literature, inertia is the results of a habit, which is formed in a longer process where many past decisions (not only the immediately previous one) remain in the memory of the consumer and influence behavior. In this study we use panel data...

  20. KIC 10080943: An eccentric binary system containing two pressure and gravity mode hybrid pulsators

    CERN Document Server

    Schmid, V S; Aerts, C; Degroote, P; Bloemen, S; Murphy, S J; Van Reeth, T; Papics, P I; Bedding, T R; Keen, M A; Prsa, A; Menu, J; Debosscher, J; Hrudkova, M; De Smedt, K; Lombaert, R; Nemeth, P

    2015-01-01

    Gamma Doradus and delta Scuti pulsators cover the transition region between low mass and massive main-sequence stars, and are as such critical for testing stellar models. When they reside in binary systems, we can combine two independent methods to derive critical information, such as precise fundamental parameters to aid asteroseismic modelling. In the Kepler light curve of KIC10080943, clear signatures of gravity and pressure mode pulsations have been found. Ground-based spectroscopy revealed this target to be a double-lined binary system. We present the analysis of four years of Kepler photometry and high-resolution spectroscopy to derive observational constraints, which will serve to evaluate theoretical predictions of the stellar structure and evolution for intermediate-mass stars. We used the method of spectral disentangling to determine atmospheric parameters for both components and derive the orbital elements. With phoebe we modelled the ellipsoidal variation and reflection signal of the binary in the...

  1. Grating-based interferometry and hybrid photon counting detectors: Towards a new era in X-ray medical imaging

    Energy Technology Data Exchange (ETDEWEB)

    Gkoumas, Spyridon, E-mail: spyridon.gkoumas@psi.ch [Swiss Light Source, Paul Scherrer Institut, Villigen 5232 (Switzerland); Wang, Zhentian; Abis, Matteo; Arboleda, Carolina [Swiss Light Source, Paul Scherrer Institut, Villigen 5232 (Switzerland); Institute for Biomedical Engineering,University and ETH Zurich, Zurich 8092 (Switzerland); Tudosie, George; Donath, Tilman; Brönnimann, Christian; Schulze-Briese, Clemens [Dectris Ltd., Neuenhoferstrasse 107, Baden 5400 (Switzerland); Stampanoni, Marco [Swiss Light Source, Paul Scherrer Institut, Villigen 5232 (Switzerland); Institute for Biomedical Engineering,University and ETH Zurich, Zurich 8092 (Switzerland)

    2016-02-11

    Progress in X-ray medical imaging and advances in detector developments have always been closely related. Similarly, a strong connection exists between innovations in synchrotron imaging and their implementation on table-top X-ray tube setups. The transfer of phase-based imaging to X-ray tubes can provide table-top setups with improved contrast between areas of low attenuation differences, by exploiting the unit decrement of the real part of the refractive index. Medical imaging is a potential application for such a system. Originally developed for synchrotron experiments, the novel generation of hybrid photon counting detectors is becoming increasingly popular due to their unique characteristics, such as small pixel size, negligible dark noise, fast counting and adjustable energy thresholds. Furthermore, novel room temperature semiconductor materials such as Cd(Zn)Te can provide higher quantum efficiency. In the first part of this article we review phase-contrast techniques and recent research towards medical applications. In the second part we present results and evaluate the potential of combining a table-top Talbot grating interferometry system with latest generation hybrid photon counting detectors.

  2. Reproducibility of trabecular bone score with different scan modes using dual-energy X-ray absorptiometry: a phantom study

    Energy Technology Data Exchange (ETDEWEB)

    Bandirali, Michele; Messina, Carmelo [Universita degli Studi di Milano, Scuola di Specializzazione in Radiodiagnostica, Milano (Italy); Di Leo, Giovanni [Unita di Radiologia, IRCCS Policlinico San Donato, San Donato Milanese (Italy); Pastor Lopez, Maria Juana; Ulivieri, Fabio M. [Servizio di Medicina Nucleare, Ospedale Maggiore, Mineralometria Ossea Computerizzata e Ambulatorio Malattie Metabolismo Minerale e Osseo, Milano (Italy); Mai, Alessandro [Universita degli Studi di Milano, Tecniche di Radiologia Medica, per Immagini e Radioterapia, Milano (Italy); Sardanelli, Francesco [Unita di Radiologia, IRCCS Policlinico San Donato, San Donato Milanese (Italy); Universita degli Studi di Milano, Dipartimento di Scienze Biomediche per la Salute, San Donato Milanese (Italy)

    2014-08-12

    The trabecular bone score (TBS) accounts for the bone microarchitecture and is calculated on dual-energy X-ray absorptiometry (DXA). We estimated the reproducibility of the TBS using different scan modes compared to the reproducibility bone mineral density (BMD). A spine phantom was used with a Hologic QDR-Discovery A densitometer. For each scan mode [fast array, array, high definition (HD)], 25 scans were automatically performed without phantom repositioning; a further 25 scans were performed with phantom repositioning. For each scan, the TBS was obtained. The coefficient of variation (CoV) was calculated as the ratio between standard deviation and mean; percent least significant change (LSC%) as 2.8 x CoV; reproducibility as the complement to 100 % of LSC%. Differences among scan modes were assessed using ANOVA. Without phantom repositioning, the mean TBS (mm{sup -1}) was: 1.352 (fast array), 1.321 (array), and 1.360 (HD); with phantom repositioning, it was 1.345, 1.332, and 1.362, respectively. Reproducibility of the TBS without phantom repositioning was 97.7 % (fast array), 98.3 % (array), and 98.2 % (HD); with phantom repositioning, it was 97.9 %, 98.7 %, and 98.4 %, respectively. LSC% was ≤2.26 %. Differences among scan modes were all statistically significant (p ≤ 0.019). Reproducibility of BMD was 99.1 % with all scan modes, while LSC% was from 0.86 % to 0.91 %. Reproducibility error of the TBS was 2-3-fold higher than that of BMD. Although statistically significant, differences in TBS among scan modes were within the highest LSC%. Thus, the three scan modes can be considered interchangeable. (orig.)

  3. Reproducibility of trabecular bone score with different scan modes using dual-energy X-ray absorptiometry: a phantom study.

    Science.gov (United States)

    Bandirali, Michele; Di Leo, Giovanni; Messina, Carmelo; Pastor Lopez, Maria Juana; Mai, Alessandro; Ulivieri, Fabio M; Sardanelli, Francesco

    2015-04-01

    The trabecular bone score (TBS) accounts for the bone microarchitecture and is calculated on dual-energy X-ray absorptiometry (DXA). We estimated the reproducibility of the TBS using different scan modes compared to the reproducibility bone mineral density (BMD). A spine phantom was used with a Hologic QDR-Discovery A densitometer. For each scan mode [fast array, array, high definition (HD)], 25 scans were automatically performed without phantom repositioning; a further 25 scans were performed with phantom repositioning. For each scan, the TBS was obtained. The coefficient of variation (CoV) was calculated as the ratio between standard deviation and mean; percent least significant change (LSC%) as 2.8 × CoV; reproducibility as the complement to 100 % of LSC%. Differences among scan modes were assessed using ANOVA. Without phantom repositioning, the mean TBS (mm(-1)) was: 1.352 (fast array), 1.321 (array), and 1.360 (HD); with phantom repositioning, it was 1.345, 1.332, and 1.362, respectively. Reproducibility of the TBS without phantom repositioning was 97.7 % (fast array), 98.3 % (array), and 98.2 % (HD); with phantom repositioning, it was 97.9 %, 98.7 %, and 98.4 %, respectively. LSC% was ≤ 2.26 %. Differences among scan modes were all statistically significant (p ≤ 0.019). Reproducibility of BMD was 99.1 % with all scan modes, while LSC% was from 0.86 % to 0.91 %. Reproducibility error of the TBS was 2-3-fold higher than that of BMD. Although statistically significant, differences in TBS among scan modes were within the highest LSC%. Thus, the three scan modes can be considered interchangeable.

  4. Hybrid Adaptive Ray-Moment Method (HARM2): A highly parallel method for radiation hydrodynamics on adaptive grids

    Science.gov (United States)

    Rosen, A. L.; Krumholz, M. R.; Oishi, J. S.; Lee, A. T.; Klein, R. I.

    2017-02-01

    We present a highly-parallel multi-frequency hybrid radiation hydrodynamics algorithm that combines a spatially-adaptive long characteristics method for the radiation field from point sources with a moment method that handles the diffuse radiation field produced by a volume-filling fluid. Our Hybrid Adaptive Ray-Moment Method (HARM2) operates on patch-based adaptive grids, is compatible with asynchronous time stepping, and works with any moment method. In comparison to previous long characteristics methods, we have greatly improved the parallel performance of the adaptive long-characteristics method by developing a new completely asynchronous and non-blocking communication algorithm. As a result of this improvement, our implementation achieves near-perfect scaling up to O (103) processors on distributed memory machines. We present a series of tests to demonstrate the accuracy and performance of the method.

  5. Hybrid Adaptive Ray-Moment Method (HARM$^2$): A Highly Parallel Method for Radiation Hydrodynamics on Adaptive Grids

    CERN Document Server

    Rosen, Anna L; Oishi, Jeffrey S; Lee, Aaron T; Klein, Richard I

    2016-01-01

    We present a highly-parallel multi-frequency hybrid radiation hydrodynamics algorithm that combines a spatially-adaptive long characteristics method for the radiation field from point sources with a moment method that handles the diffuse radiation field produced by a volume-filling fluid. Our Hybrid Adaptive Ray-Moment Method (HARM$^2$) operates on patch-based adaptive grids, is compatible with asynchronous time stepping, and works with any moment method. In comparison to previous long characteristics methods, we have greatly improved the parallel performance of the adaptive long-characteristics method by developing a new completely asynchronous and non-blocking communication algorithm. As a result of this improvement, our implementation achieves near-perfect scaling up to $\\mathcal{O}(10^3)$ processors on distributed memory machines. We present a series of tests to demonstrate the accuracy and performance of the method.

  6. A new hybrid algorithm using thermodynamic and backward ray-tracing approaches for modeling luminescent solar concentrators

    Energy Technology Data Exchange (ETDEWEB)

    Lo, Ch. K.; Lim, Y. S.; Tan, S. G.; Rahman, F. A. [Faculty of Engineering and Science, University Tunku Abdul Rahman, Jalan Genting Klang, 53300, Kuala Lumpur (Malaysia)

    2010-12-15

    A Luminescent Solar Concentrator (LSC) is a transparent plate containing luminescent material with photovoltaic (PV) cells attached to its edges. Sunlight entering the plate is absorbed by the luminescent material, which in turn emits light. The emitted light propagates through the plate and arrives at the PV cells through total internal reflection. The ratio of the area of the relatively cheap polymer plate to that of the expensive PV cells is increased, and the cost per unit of solar electricity can be reduced by 75%. To improve the emission performance of LSCs, simulation modeling of LSCs becomes essential. Ray-tracing modeling is a popular approach for simulating LSCs due to its great ability of modeling various LSC structures under direct and diffuse sunlight. However, this approach requires substantial amount of measurement input data. Also, the simulation time is enormous because it is a forward-ray tracing method that traces all the rays propagating from the light source to the concentrator. On the other hand, the thermodynamic approach requires substantially less input parameters and simulation time, but it can only be used to model simple LSC designs with direct sunlight. Therefore, a new hybrid model was developed to perform various simulation studies effectively without facing the issues arisen from the existing ray-tracing and thermodynamic models. The simulation results show that at least 60% of the total output irradiance of a LSC is contributed by the light trapped and channeled by the LSC. The novelty of this hybrid model is the concept of integrating the thermodynamic model with a well-developed Radiance ray-tracing model, hence making this model as a fast, powerful and cost-effective tool for the design of LSCs. (authors)

  7. A New Hybrid Algorithm Using Thermodynamic and Backward Ray-Tracing Approaches for Modeling Luminescent Solar Concentrators

    Directory of Open Access Journals (Sweden)

    Chin Kim Lo

    2010-11-01

    Full Text Available A Luminescent Solar Concentrator (LSC is a transparent plate containing luminescent material with photovoltaic (PV cells attached to its edges. Sunlight entering the plate is absorbed by the luminescent material, which in turn emits light. The emitted light propagates through the plate and arrives at the PV cells through total internal reflection. The ratio of the area of the relatively cheap polymer plate to that of the expensive PV cells is increased, and the cost per unit of solar electricity can be reduced by 75%. To improve the emission performance of LSCs, simulation modeling of LSCs becomes essential. Ray-tracing modeling is a popular approach for simulating LSCs due to its great ability of modeling various LSC structures under direct and diffuse sunlight. However, this approach requires substantial amount of measurement input data. Also, the simulation time is enormous because it is a forward-ray tracing method that traces all the rays propagating from the light source to the concentrator. On the other hand, the thermodynamic approach requires substantially less input parameters and simulation time, but it can only be used to model simple LSC designs with direct sunlight. Therefore, a new hybrid model was developed to perform various simulation studies effectively without facing the issues arisen from the existing ray-tracing and thermodynamic models. The simulation results show that at least 60% of the total output irradiance of a LSC is contributed by the light trapped and channeled by the LSC. The novelty of this hybrid model is the concept of integrating the thermodynamic model with a well-developed Radiance ray-tracing model, hence making this model as a fast, powerful and cost-effective tool for the design of LSCs.

  8. In situ micro-focused X-ray beam characterization with a lensless camera using a hybrid pixel detector

    Energy Technology Data Exchange (ETDEWEB)

    Kachatkou, Anton, E-mail: anton.kachatkou@manchester.ac.uk [The University of Manchester, Sackville Street Building, Manchester M13 9PL (United Kingdom); Marchal, Julien [Diamond Light Source Ltd, Diamond House, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE (United Kingdom); Silfhout, Roelof van, E-mail: anton.kachatkou@manchester.ac.uk [The University of Manchester, Sackville Street Building, Manchester M13 9PL (United Kingdom)

    2014-02-04

    Position and size measurements of a micro-focused X-ray beam, using an X-ray beam imaging device based on a lensless camera that collects radiation scattered from a thin foil placed in the path of the beam at an oblique angle, are reported. Results of studies on micro-focused X-ray beam diagnostics using an X-ray beam imaging (XBI) instrument based on the idea of recording radiation scattered from a thin foil of a low-Z material with a lensless camera are reported. The XBI instrument captures magnified images of the scattering region within the foil as illuminated by the incident beam. These images contain information about beam size, beam position and beam intensity that is extracted during dedicated signal processing steps. In this work the use of the device with beams for which the beam size is significantly smaller than that of a single detector pixel is explored. The performance of the XBI device equipped with a state-of-the-art hybrid pixel X-ray imaging sensor is analysed. Compared with traditional methods such as slit edge or wire scanners, the XBI micro-focused beam characterization is significantly faster and does not interfere with on-going experiments. The challenges associated with measuring micrometre-sized beams are described and ways of optimizing the resolution of beam position and size measurements of the XBI instrument are discussed.

  9. Hybrid confinement of optical and mechanical modes in a bullseye optomechanical resonator.

    Science.gov (United States)

    Santos, Felipe G S; Espinel, Yovanny A V; Luiz, Gustavo O; Benevides, Rodrigo S; Wiederhecker, Gustavo S; Mayer Alegre, Thiago P

    2017-01-23

    Optomechanical cavities have proven to be an exceptional tool to explore fundamental and applied aspects of the interaction between mechanical and optical waves. Here we demonstrate a novel optomechanical cavity based on a disk with a radial mechanical bandgap. This design confines light and mechanical waves through distinct physical mechanisms which allows for independent control of the mechanical and optical properties. Simulations foresee an optomechanical coupling rate g0 reaching 2π × 100 kHz for mechanical frequencies around 5 GHz as well as anchor loss suppression of 60 dB. Our device design is not limited by unique material properties and could be easily adapted to allow for large optomechanical coupling and high mechanical quality factors with other promising materials. Finally, our devices were fabricated in a commercial silicon photonics facility, demonstrating g0/2π = 23 kHz for mechanical modes with frequencies around 2 GHz and mechanical Q-factors as high as 2300 at room temperature, also showing that our approach can be easily scalable and useful as a new platform for multimode optomechanics.

  10. Numerical Modeling of the Sensitivity of X-Ray Driven Implosions to Low-Mode Flux Asymmetries

    CERN Document Server

    Scott, R H H; Bradley, D K; Callahan, D A; Edwards, M J; Haan, S W; Jones, O S; Spears, B K; Marinak, M M; Town, R P J; Norreys, P A; Suter, L J

    2012-01-01

    The sensitivity of inertial confinement fusion implosions of the type performed on the National Ignition Facility (NIF) to low-mode flux asymmetries has been investigated numerically. It is shown that large-amplitude, low-order mode shapes (Legendre polynomial P4), resulting from associated low order flux asymmetries, cause spatial variations in capsule and fuel momentum that prevent the DT ice layer from being decelerated uniformly by the hot spot pressure. This reduces the transfer of kinetic to internal energy of the central hot spot, thus reducing neutron yield. Furthermore, synthetic gated x-ray images of the hot spot self-emission indicate that P4 shapes may be unquantifiable for DT layered capsules. Instead the positive P4 asymmetry aliases itself as an oblate P4 in the x-ray self emission images. Correction of this apparent P2 distortion can further distort the implosion while creating a round x-ray image. Long wavelength asymmetries may be playing a significant role in the observed yield reduction of...

  11. Isotope effects in liquid water probed by transmission mode x-ray absorption spectroscopy at the oxygen K-edge

    Science.gov (United States)

    Schreck, Simon; Wernet, Philippe

    2016-09-01

    The effects of isotope substitution in liquid water are probed by x-ray absorption spectroscopy at the O K-edge as measured in transmission mode. Confirming earlier x-ray Raman scattering experiments, the D2O spectrum is found to be blue shifted with respect to H2O, and the D2O spectrum to be less broadened. Following the earlier interpretations of UV and x-ray Raman spectra, the shift is related to the difference in ground-state zero-point energies between D2O and H2O, while the difference in broadening is related to the difference in ground-state vibrational zero-point distributions. We demonstrate that the transmission-mode measurements allow for determining the spectral shapes with unprecedented accuracy. Owing in addition to the increased spectral resolution and signal to noise ratio compared to the earlier measurements, the new data enable the stringent determination of blue shift and broadening in the O K-edge x-ray absorption spectrum of liquid water upon isotope substitution. The results are compared to UV absorption data, and it is discussed to which extent they reflect the differences in zero-point energies and vibrational zero-point distributions in the ground-states of the liquids. The influence of the shape of the final-state potential, inclusion of the Franck-Condon structure, and differences between liquid H2O and D2O resulting from different hydrogen-bond environments in the liquids are addressed. The differences between the O K-edge absorption spectra of water from our transmission-mode measurements and from the state-of-the-art x-ray Raman scattering experiments are discussed in addition. The experimentally extracted values of blue shift and broadening are proposed to serve as a test for calculations of ground-state zero-point energies and vibrational zero-point distributions in liquid H2O and D2O. This clearly motivates the need for new calculations of the O K-edge x-ray absorption spectrum of liquid water.

  12. Hybrid plasmonic gap modes in metal film-coupled dimers and their physical origins revealed by polarization resolved dark field spectroscopy

    Science.gov (United States)

    Li, Guang-Can; Zhang, Yong-Liang; Lei, Dang Yuan

    2016-03-01

    Plasmonic gap modes sustained by metal film-coupled nanostructures have recently attracted extensive research attention due to flexible control over their spectral response and significantly enhanced field intensities at the particle-film junction. In this work, by adopting an improved dark field spectroscopy methodology - polarization resolved spectral decomposition and colour decoding - we are able to ``visualize'' and distinguish unambiguously the spectral and far field radiation properties of the complex plasmonic gap modes in metal film-coupled nanosphere monomers and dimers. Together with full-wave numerical simulation results, it is found that while the monomer-film system supports two hybridized dipole-like plasmon modes having different oscillating orientations and resonance strengths, the scattering spectrum of the dimer-film system features two additional peaks, one strong yet narrow resonant mode corresponding to a bonding dipolar moment and one hybridized higher order resonant mode, both polarized along the dimer axis. In particular, we demonstrate that the polarization dependent scattering radiation of the film-coupled nanosphere dimer can be used to optically distinguish from monomers and concurrently determine the spatial orientation of the dimer with significantly improved accuracy at the single-particle level, illustrating a simple yet highly sensitive plasmon resonance based nanometrology method.Plasmonic gap modes sustained by metal film-coupled nanostructures have recently attracted extensive research attention due to flexible control over their spectral response and significantly enhanced field intensities at the particle-film junction. In this work, by adopting an improved dark field spectroscopy methodology - polarization resolved spectral decomposition and colour decoding - we are able to ``visualize'' and distinguish unambiguously the spectral and far field radiation properties of the complex plasmonic gap modes in metal film

  13. Confirmation of simultaneous p and g mode excitation in HD 8801 and Gamma Peg from time-resolved multicolour photometry of six candidate "hybrid" pulsators

    CERN Document Server

    Handler, G

    2009-01-01

    We carried out a multi-colour time-series photometric study of six stars claimed as "hybrid" p and g mode pulsators in the literature. Gamma Peg was confirmed to show short-period oscillations of the Beta Cep type and simultaneous long-period pulsations typical of Slowly Pulsating B (SPB) stars. From the measured amplitude ratios in the Stromgren uvy passbands, the stronger of the two short period pulsation modes was identified as radial; the second is l=1. Three of the four SPB-type modes are most likely l=1 or 2. Comparison with theoretical model calculations suggests that Gamma Peg is either an 8.5 solar mass radial fundamental mode pulsator or a 9.6 solar mass first radial overtone pulsator. HD 8801 was corroborated as a "hybrid" Delta Sct Gamma Dor star; four pulsation modes of the Gamma Dor type were detected, and two modes of the Delta Sct type were confirmed. Two pulsational signals between the frequency domains of these two known classes of variables were confirmed and another was newly detected. The...

  14. Iodinated silica/porphyrin hybrid nanoparticles for X-ray computed tomography/fluorescence dual-modal imaging of tumors

    Directory of Open Access Journals (Sweden)

    Koichiro Hayashi

    2014-12-01

    Full Text Available Silica nanoparticles containing covalently linked iodine and a near-infrared (NIR fluorescence dye, namely porphyrin, have been synthesized through a one-pot sol–gel reaction. These particles are called iodinated silica/porphyrin hybrid nanoparticles (ISP HNPs. The ISP HNPs have both high X-ray absorption coefficient and NIR fluorescence. The ISP HNPs modified with folic acid (FA and polyethylene glycol (PEG, denoted as FA-PEG-ISP HNPs, enabled the successful visualization of tumors in mice by both X-ray computed tomography (CT and fluorescence imaging (FI. Thus, the FA-PEG-ISP HNPs are useful as contrast agents or probes for CT/FI dual-modal imaging.

  15. Sound propagation in two-axis underwater channel based on beam-displacement ray-mode theory

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Sound propagation in a deep ocean two-axis underwater channel is often complex and difficult to simulate between surface channel and sound fixing and ranging (SOFAR) channel. The beam-displacement ray-mode (BDRM) theory is a normal mode method for propagation modeling in horizontally stratified shallow water. An improved method for computing the upper boundary reflection coefficient in the BDRM is proposed and applied to calculate the acoustic fields of a two-axis underwater channel. Transmission losses in the two-axis underwater channel are calculated in the new BDRM. The corresponding results are in good agreement with those from the Kraken code, and furthermore the computed speed of the new BDRM excels the other methods.

  16. Simple synchronization technique of a mode-locked laser for Laser-Compton scattering γ-ray source

    Science.gov (United States)

    Mori, Michiaki; Kosuge, Atsushi; Kiriyama, Hiromitsu; Hajima, Ryoichi; Kondo, Kiminori

    2016-06-01

    We propose a simple and effective synchronization technique between a reference electrical oscillator and a mode-locked laser for a narrowband picosecond Laser-Compton scattering γ-ray source by using a commercial-based 1-chip frequency synthesizer, which is widely used in radio communication. The mode-locked laser has been successfully synchronized in time with a jitter of 180 fs RMS for 10 Hz-100 kHz bandwidth. A good stability of 640 μHz at 80 MHz repetition rate for 10 h operation has also been confirmed. We discuss in detail the design and performance of this technique (in terms of timing jitter, stability, and validity).

  17. A dual-mode phase-shift modulation control scheme for voltage multiplier based X-ray power supply

    Energy Technology Data Exchange (ETDEWEB)

    Iqbal, S [School of Electrical and Electronics Engineering, University Sains Malaysia, 14300 Nibong Tebal, Pulau Pinang (Malaysia); Besar, R; Venkataseshaiah, C, E-mail: shahidsidu@hotmail.co [Faculty of Engineering and Technology, Multimedia University, 75450 Melaka (Malaysia)

    2010-05-15

    This paper proposes a dual-mode phase-shift modulation control scheme for series resonant inverter fed voltage multiplier (VM) based X-ray power supply. In this control scheme the outputs voltage of two parallel connected series resonant inverters are mixed before supplying to VM circuit. The output voltage of the power supply is controlled by varying the phase-shift between the output voltages of two inverters. In order to achieve quick rise of output voltage, the power supply is started with zero phase-shift and as the output voltage reaches 90% of the target voltage, the phase-shift is increased to a value which corresponds to target output voltage to prevent overshoot. The proposed control scheme has been shown to have good performance. Experimental results based on the scaled-down laboratory prototype are presented to validate the effectiveness of proposed dual-mode phase shift modulation control scheme.

  18. Development of Real-Time Dual-Display Handheld and Bench-Top Hybrid-Mode SD-OCTs

    Directory of Open Access Journals (Sweden)

    Nam Hyun Cho

    2014-01-01

    Full Text Available Development of a dual-display handheld optical coherence tomography (OCT system for retina and optic-nerve-head diagnosis beyond the volunteer motion constraints is reported. The developed system is portable and easily movable, containing the compact portable OCT system that includes the handheld probe and computer. Eye posterior chambers were diagnosed using the handheld probe, and the probe could be fixed to the bench-top cradle depending on the volunteers’ physical condition. The images obtained using this handheld probe were displayed in real time on the computer monitor and on a small secondary built-in monitor; the displayed images were saved using the handheld probe’s built-in button. Large-scale signal-processing procedures such as k-domain linearization, fast Fourier transform (FFT, and log-scaling signal processing can be rapidly applied using graphics-processing-unit (GPU accelerated processing rather than central-processing-unit (CPU processing. The Labview-based system resolution is 1,024 × 512 pixels, and the frame rate is 56 frames/s, useful for real-time display. The 3D images of the posterior chambers including the retina, optic-nerve head, blood vessels, and optic nerve were composed using real-time displayed images with 500 × 500 × 500 pixel resolution. A handheld and bench-top hybrid mode with a dual-display handheld OCT was developed to overcome the drawbacks of the conventional method.

  19. Design of High-Voltage Switch-Mode Power Amplifier Based on Digital-Controlled Hybrid Multilevel Converter

    Directory of Open Access Journals (Sweden)

    Yanbin Hou

    2016-01-01

    Full Text Available Compared with conventional Class-A, Class-B, and Class-AB amplifiers, Class-D amplifier, also known as switching amplifier, employs pulse width modulation (PWM technology and solid-state switching devices, capable of achieving much higher efficiency. However, PWM-based switching amplifier is usually designed for low-voltage application, offering a maximum output voltage of several hundred Volts. Therefore, a step-up transformer is indispensably adopted in PWM-based Class-D amplifier to produce high-voltage output. In this paper, a switching amplifier without step-up transformer is developed based on digital pulse step modulation (PSM and hybrid multilevel converter. Under the control of input signal, cascaded power converters with separate DC sources operate in PSM switch mode to directly generate high-voltage and high-power output. The relevant topological structure, operating principle, and design scheme are introduced. Finally, a prototype system is built, which can provide power up to 1400 Watts and peak voltage up to ±1700 Volts. And the performance, including efficiency, linearity, and distortion, is evaluated by experimental tests.

  20. A Compact High-Pass Filter Using Hybrid Microstrip/Nonuniform CPW with Dual-Mode Resonant Response

    Directory of Open Access Journals (Sweden)

    Hui Chen

    2016-01-01

    Full Text Available A novel and miniature high-pass filter (HPF based on a hybrid-coupled microstrip/nonuniform coplanar waveguide (CPW resonator is proposed in this article, in which the designed CPW has exhibited a wideband dual-mode characteristic within the desired high-pass frequency range. The implemented filter consists of the top microstrip coupled patches and the bottom modified nonuniformly short-circuited CPW resonator. Simulated results from the electromagnetic (EM analysis software and measured results from a vector network analyzer (VNA show a good agreement. A designed and fabricated prototype filter having a 3 dB cutoff frequency (fc of 5.78 GHz has shown an ultrawide high-pass behavior, which exhibits the highest passband frequency exceeding 4.0fc under the minimum insertion loss (IL 0.75 dB. The printed circuit board (PCB area of the filter is approximately 0.062λg×0.093λg, where λg is the guided wavelength at fc.

  1. Influence of gas puff location on the coupling of lower hybrid waves in JET ELMy H-mode plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Ekedahl, A. [CEA, IRFM, France; Petrzilka, V. [Assoc. Euratom-IPP.CR, Czech Republic; Baranov, Y. [EURATOM / UKAEA, UK; Brix, M [UKAEA Fusion, Culham UK; Goniche, M. [CEA, IRFM, France; Jacquet, P. [EURATOM / UKAEA, Abingdon, UK; Kirov, K K [Association EURATOM-CCFE, Abingdon, UK; Klepper, C Christopher [ORNL; Mailloux, J. [EURATOM / UKAEA, UK; Mayoral, M.-L. [EURATOM / UKAEA, UK; Nave, M. F. F. [Association EURATOM/IST, Lisbon, Portugal; Ongena, J. [Laboratory for Plasma Physics-ERM/KMS (LPP-ERM/KMS), Brussels, Belgium

    2012-01-01

    Reliable coupling of the lower hybrid current drive (LHCD) to H-mode plasmas in JET is made feasible through a dedicated gas injection system, located at the outer wall and magnetically connected to the antenna (Pericoli Ridolfini et al 2004 Plasma Phys. Control. Fusion 46 349, Ekedahl et al 2005 Nucl. Fusion 45 351, Ekedahl et al 2009 Plasma Phys. Control. Fusion 51 044001). An experiment was carried out in JET in order to investigate whether a gas injection from the top of the torus, as is foreseen for the main gas injection in ITER, could also provide good coupling of the LH waves if magnetically connected to the antenna. The results show that a top gas injection was not efficient for providing a reliable LHCD power injection, in spite of being magnetically connected and in spite of using almost twice the amount of gas flow compared with the dedicated outer mid-plane gas puffing system. A dedicated gas injection system, set in the outer wall and magnetically connected to the LHCD antenna, is therefore recommended in order to provide the reliable coupling conditions for an LHCD antenna in ITER.

  2. Design of a control system for ultrafast x-ray camera working in a single photon counting mode

    Science.gov (United States)

    Zoladz, Miroslaw; Rauza, Jacek; Kasinski, Krzysztof; Maj, Piotr; Grybos, Pawel

    2015-09-01

    Prototype of Ultra-Fast X-Ray Camera Controller working in a single photon counting mode and based on ASIC has been presented in this paper. An ASIC architecture has been discussed with special attention to digital part. We present the Custom Soft Processor as an ASIC control sequences generator. The Processor allows for dynamic program downloading and generating control sequences with up to 80MHz clock rate (preliminary results). Assembler with a very simple syntax has been defined to speed up Processor programs development. Discriminators threshold dispersion correction has been performed to confirm proper Camera Controller operation.

  3. Measurement of the Proton-Air Cross Section with Telescope Array's Middle Drum Detector and Surface Array in Hybrid Mode

    CERN Document Server

    Abbasi, R U; Abu-Zayyad, T; Allen, M; Anderson, R; Azuma, R; Barcikowski, E; Belz, J W; Bergman, D R; Blake, S A; Cady, R; Chae, M J; Cheon, B G; Chiba, J; Chikawa, M; Cho, W R; Fujii, T; Fukushima, M; Goto, T; Hanlon, W; Hayashi, Y; Hayashida, N; Hibino, K; Honda1, K; Ikeda, D; Inoue, N; Ishii, T; Ishimori, R; Ito, H; Ivanov, D; Jui, C C H; Kadota, K; Kakimoto, F; Kalashev, O; Kasahara, K; Kawai, H; Kawakami, S; Kawana, S; Kawata, K; Kido, E; Kim, H B; Kim, J H; Kitamura, S; Kitamura, Y; Kuzmin, V; Kwon, Y J; Lan1, J; Lim, S I; Lundquist, J P; Machida, K; Martens, K; Matsuda, T; Matsuyama, T; Matthews, J N; Minamino, M; Mukai, K; Myers, I; Nagasawa, K; Nagataki1, S; Nakamura, T; Nonaka, T; Nozato, A; Ogio, S; Ogura, J; Ohnishi, M; Ohoka, H; Oki, K; Okuda, T; Ono, M; Oshima, A; Ozawa, S; Park, I H; Pshirkov, M S; Rodriguez, D C; Rubtsov, G; Ryu, D; Sagawa, H; Sakurai, N; Sampson, A L; Scott, L M; Shah, P D; Shibata, F; Shibata, T; Shimodaira, H; Shin, B K; Smith, J D; Sokolsky, P; Springer, R W; Stokes, B T; Stratton, S R; Stroman, T A; Suzawa, T; Takamura, M; Takeda, M; Takeishi, R; Taketa, A; Takita, M; Tameda, Y; Tanaka, H; Tanaka, K; Tanaka, M; Thomas, S B; Thomson, G B; Tinyakov, P; Tkachev, I; Tokuno, H; Tomida, T; Troitsky, S; Tsunesada, Y; Tsutsumi, K; Uchihori, Y; Udo, S; Urban, F; Vasiloff, G; Wong, T; Yamane, R; Yamaoka, H; Yamazaki, K; Yang, J; Yashiro, K; Yoneda, Y; Yoshida, S; Yoshii, H; Zollinger, R; Zundel, Z

    2015-01-01

    In this work we are reporting on the measurement of the proton-air inelastic cross section $\\sigma^{\\rm inel}_{\\rm p-air}$ using the Telescope Array (TA) detector. Based on the measurement of the $\\sigma^{\\rm inel}_{\\rm p-air}$ the proton-proton cross section $\\sigma_{\\rm p-p}$ value is also determined at $\\sqrt{s} = 95$ TeV. Detecting cosmic ray events at ultra high energies with Telescope Array enables us to study this fundamental parameter that we are otherwise unable to access with particle accelerators. The data used in this report is collected over five years using hybrid events observed by the Middle Drum fluorescence detector together with the surface array detector. The value of the $\\sigma^{\\rm inel}_{\\rm p-air}$ is found to be equal to $ 567.0 \\pm 70.5 [{\\rm Stat.}] ^{+25}_{-29} [{\\rm Sys.}]$ mb. The total proton-proton cross section is subsequently inferred from Glauber Formalism and Block, Halzen and Stanev QCD inspired fit and is found to be equal to $170_{-44}^{+48} [{\\rm Stat.}] \\pm _{-19}^{+1...

  4. Search for Gamma-Ray Bursts with the ARGO-YBJ Detector in Shower Mode

    Science.gov (United States)

    Bartoli, B.; Bernardini, P.; Bi, X. J.; Cao, Z.; Catalanotti, S.; Chen, S. Z.; Chen, T. L.; Cui, S. W.; Dai, B. Z.; D'Amone, A.; Danzengluobu; De Mitri, I.; D'Ettorre Piazzoli, B.; Di Girolamo, T.; Di Sciascio, G.; Feng, C. F.; Feng, Zhaoyang; Feng, Zhenyong; Gao, W.; Gou, Q. B.; Guo, Y. Q.; He, H. H.; Hu, Haibing; Hu, Hongbo; Iacovacci, M.; Iuppa, R.; Jia, H. Y.; Labaciren; Li, H. J.; Liu, C.; Liu, J.; Liu, M. Y.; Lu, H.; Ma, L. L.; Ma, X. H.; Mancarella, G.; Mari, S. M.; Marsella, G.; Mastroianni, S.; Montini, P.; Ning, C. C.; Perrone, L.; Pistilli, P.; Salvini, P.; Santonico, R.; Shen, P. R.; Sheng, X. D.; Shi, F.; Surdo, A.; Tan, Y. H.; Vallania, P.; Vernetto, S.; Vigorito, C.; Wang, H.; Wu, C. Y.; Wu, H. R.; Xue, L.; Yang, Q. Y.; Yang, X. C.; Yao, Z. G.; Yuan, A. F.; Zha, M.; Zhang, H. M.; Zhang, L.; Zhang, X. Y.; Zhang, Y.; Zhao, J.; Zhaxiciren; Zhaxisangzhu; Zhou, X. X.; Zhu, F. R.; Zhu, Q. Q.; ARGO-YBJ Collaboration

    2017-06-01

    The ARGO-YBJ detector, located at the Yangbajing Cosmic Ray Laboratory (4300 m a. s. l., Tibet, China), was a “full coverage” (central carpet with an active area of ˜93%) air shower array dedicated to gamma-ray astronomy and cosmic-ray studies. The wide field of view (˜2 sr) and high duty cycle (>86%), made ARGO-YBJ suitable to search for short and unexpected gamma-ray emissions like gamma-ray bursts (GRBs). Between 2007 November 6 and 2013 February 7, 156 satellite-triggered GRBs (24 of them with known redshift) occurred within the ARGO-YBJ field of view (zenith angle θ ≤ 45°). A search for possible emission associated with these GRBs has been made in the two energy ranges 10-100 GeV and 10-1000 GeV. No significant excess has been found in time coincidence with the satellite detections nor in a set of different time windows inside the interval of one hour after the bursts. Taking into account the EBL absorption, upper limits to the energy fluence at a 99% confidence level have been evaluated, with values ranging from ˜10-5 erg cm-2 to ˜10-1 erg cm-2. The Fermi-GBM burst GRB 090902B, with a high-energy photon of 33.4 GeV detected by Fermi-LAT, is discussed in detail.

  5. A hybrid Monte Carlo model for the energy response functions of X-ray photon counting detectors

    Science.gov (United States)

    Wu, Dufan; Xu, Xiaofei; Zhang, Li; Wang, Sen

    2016-09-01

    In photon counting computed tomography (CT), it is vital to know the energy response functions of the detector for noise estimation and system optimization. Empirical methods lack flexibility and Monte Carlo simulations require too much knowledge of the detector. In this paper, we proposed a hybrid Monte Carlo model for the energy response functions of photon counting detectors in X-ray medical applications. GEANT4 was used to model the energy deposition of X-rays in the detector. Then numerical models were used to describe the process of charge sharing, anti-charge sharing and spectral broadening, which were too complicated to be included in the Monte Carlo model. Several free parameters were introduced in the numerical models, and they could be calibrated from experimental measurements such as X-ray fluorescence from metal elements. The method was used to model the energy response function of an XCounter Flite X1 photon counting detector. The parameters of the model were calibrated with fluorescence measurements. The model was further tested against measured spectrums of a VJ X-ray source to validate its feasibility and accuracy.

  6. A hybrid Monte Carlo model for the energy response functions of X-ray photon counting detectors

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Dufan; Xu, Xiaofei [Key Laboratory of Particle & Radiation Imaging, Tsinghua University, Ministry of Education (China); Department of Engineering Physics, Tsinghua University, Beijing 100084 (China); Zhang, Li, E-mail: zli@mail.tsinghua.edu.cn [Key Laboratory of Particle & Radiation Imaging, Tsinghua University, Ministry of Education (China); Department of Engineering Physics, Tsinghua University, Beijing 100084 (China); Wang, Sen [Key Laboratory of Particle & Radiation Imaging, Tsinghua University, Ministry of Education (China); Department of Engineering Physics, Tsinghua University, Beijing 100084 (China)

    2016-09-11

    In photon counting computed tomography (CT), it is vital to know the energy response functions of the detector for noise estimation and system optimization. Empirical methods lack flexibility and Monte Carlo simulations require too much knowledge of the detector. In this paper, we proposed a hybrid Monte Carlo model for the energy response functions of photon counting detectors in X-ray medical applications. GEANT4 was used to model the energy deposition of X-rays in the detector. Then numerical models were used to describe the process of charge sharing, anti-charge sharing and spectral broadening, which were too complicated to be included in the Monte Carlo model. Several free parameters were introduced in the numerical models, and they could be calibrated from experimental measurements such as X-ray fluorescence from metal elements. The method was used to model the energy response function of an XCounter Flite X1 photon counting detector. The parameters of the model were calibrated with fluorescence measurements. The model was further tested against measured spectrums of a VJ X-ray source to validate its feasibility and accuracy.

  7. The Three-Dimensional Ray Trajectories of the WKB Optical Fiber Modes

    Science.gov (United States)

    1993-03-01

    source-free, homogeneous media , we have [Vt+k 2(r)]E=0, (2-1) where k(r) is the wave number and E is the electric field. It is noted that this equation...homogeneous media , we have optical fibers, the approximate Eikonal ray approach [21, which in turn is based on Fermat’s [V+k2()=E-l) extremum...that (r, 0, z) locate the ray , For purposes of analysis the geometrica relationships are more carefully defined in the nex’ Figure 31: Geometry of the

  8. Dual-wavelength passive and hybrid mode-locking of 3, 4.5 and 10 GHz InAs/InP(100) quantum dot lasers.

    Science.gov (United States)

    Tahvili, M S; Du, L; Heck, M J R; Nötzel, R; Smit, M K; Bente, E A J M

    2012-03-26

    We present an investigation of passive and hybrid mode-locking in Fabry-Pérot type two-section InAs/InP(100) quantum dot lasers that show dual wavelength operation. Over the whole current and voltage range for mode-locking of these lasers, the optical output spectra show two distinct lobes. The two lobes provide a coherent bandwidth and are verified to lead to two synchronized optical pulses. The generated optical pulses are elongated in time due to a chirp which shows opposite signs over the two spectral lobes. Self-induced mode-locking in the single-section laser shows that the dual-wavelength spectra correspond to emission from ground state. In the hybrid mode-locking regime, a map of locking range is presented by measuring the values of timing jitter for several values of power and frequency of the external electrical modulating signal. An overview of the systematic behavior of InAs/InP(100) quantum dot mode-locked lasers is presented as conclusion.

  9. Fertility assessment in hybrids between monobrachially homologous Rb races of the house mouse from the island of Madeira: implications for modes of chromosomal evolution.

    Science.gov (United States)

    Nunes, A C; Catalan, J; Lopez, J; Ramalhinho, M da Graça; Mathias, M da Luz; Britton-Davidian, J

    2011-02-01

    The speciation model of divergence by monobrachially homologous fusions (that is, with one arm in common) benefits from a wide conceptual acceptance, because heterozygotes between populations carrying such fusions suffer from high levels of meiotic dysfunction. The same meiotic configurations can also be generated by WART (whole-arm reciprocal translocation), rearrangements that are known to occur in mammals. Estimating the disadvantage of heterozygotes carrying monobrachially homologous fusions is required to evaluate the relevance of this mode of chromosomal evolution in diversification and speciation. House mice are an excellent study models because chromosomal races exist carrying monobrachially homologous fusions, and WARTs have been documented in this species. The fertility of heterozygote mice carrying the smallest number of monobrachially homologous fusions (that is, a chain of four chromosomes, C4) was investigated in laboratory-bred hybrids between two parapatric chromosomal races from the island of Madeira. Meiotic nondisjunction analyses and histological sections of testes showed that aneuploidy (16.7%) and germ cell death (50.9%) rates reached significantly higher mean values in hybrids than in homozygotes. In females, however, the histological analysis of ovarian follicle parameters revealed no significant differences between hybrid and homozygous individuals. Overall, the reproductive assays indicated that these C4-carrying hybrids were not sterile but showed an approximately 50% decrease in fertility compared to homozygous parental mice. Implications for modes of chromosomal evolution involving monobrachially homologous fusions are discussed.

  10. Influence of light-polymerization modes on the degree of conversion and mechanical properties of resin composites: a comparative analysis between a hybrid and a nanofilled composite.

    Science.gov (United States)

    da Silva, Eduardo Moreira; Poskus, Laiza Tatiana; Guimarães, José Guilherme Antunes

    2008-01-01

    This study analyzed the influence of the light polymerization mode on the degree of conversion (DC) and mechanical properties of two resin composites: a hybrid (Filtek P60) and a nanofilled composite (Filtek Supreme). The composites were light activated by three light polymerization modes (Standard-S: 650 mW/cm2 for 30 seconds; High intensity-H: 1000 mW/cm2 for 20 seconds and Gradual-G: 100 up to 1000 mW/cm2 for 10 seconds + 1000 mW/cm2 for 10 seconds). The DC (%) was measured by FT-Raman spectroscopy. Flexural strength and flexural modulus were obtained from bar-shaped specimens (1 x 2 x 10 mm) submitted to the three-point bending test. Microhardness was evaluated by Knoop indentation (KHN). Data were analyzed by ANOVA and Student-Newman-Keuls multiple range test and linear regression analysis. The results showed the following DC: H > S > G (p hybrid > nanofilled (p S = G (p hybrid composite presented higher flexural strength and flexural modulus than the nanofilled composite (p composites (p = 0.1605). The results suggest that nanofilled composites may present a lower degree of conversion and reduced mechanical properties compared to hybrid composites.

  11. A 5G Hybrid Channel Model Considering Rays and Geometric Stochastic Propagation Graph

    DEFF Research Database (Denmark)

    Steinböck, Gerhard; Karstensen, Anders; Kyösti, Pekka;

    2016-01-01

    We consider a ray-tracing tool, in particular the METIS map based model for deterministic simulation of the channel impulse response. The ray-tracing tool is extended by adding a geometric stochastic propagation graph to model additional stochastic paths and the dense multipath components observed...... simplistic, e.g. plain walls and thus neglecting the structures on the building facades, window frames, window sills, etc. Thus in measurements there are often additional components observed that are not captured by these simplistic ray-tracing implementations. In this contribution we introduce a flexible...

  12. Quasi-linearly polarized hybrid modes in tapered and metal-coated tips with circular apertures: understanding the functionality of aperture tips

    Science.gov (United States)

    Tugchin, B. N.; Janunts, N.; Steinert, M.; Dietrich, K.; Kley, E. B.; Tünnermann, A.; Pertsch, T.

    2017-06-01

    In this study, we investigate analytically and experimentally the roles of quasi-linearly polarized (LP), hybrid, plasmonic and photonic modes in optical detection and excitation with aperture tips in scanning near-field optical microscopy. Aperture tips are tapered and metal-coated optical fibers where small circular apertures are made at the apex. In aperture tips, there exist plasmonic modes that are bound at the interface of the metal cladding to the inner dielectric fiber and photonic modes that are guided in the area of the increased index in the dielectric fiber core. The fundamental photonic mode, although excited by the free-space Gaussian beam, experiences cutoff and turns into an evanescent mode. The photonic mode also becomes lossier than the plasmonic mode toward the tip aperture, and its power decay due to absorption and reflection is expected to be at least 10-9. In contrast, the fundamental plasmonic mode has no cutoff and thus reaches all the way to the tip aperture. Due to the non-adiabaticity of both modes’ propagations through the taper below a core radius of 600 nm, there occurs coupling between the modes. The transmission efficiency of the plasmonic mode, including the coupling efficiency and the propagation loss, is expected to be about 10-6 that is at least 3 orders of magnitude larger than that of the photonic mode. Toward the tip aperture, the longitudinal field of the photonic mode becomes stronger than the transverse ones while the transverse fields always dominate for the plasmonic mode. Experimentally, we obtain polarization resolved images of the near-field at the tip aperture and compare with the x- and y-components of the fundamental quasi-LP plasmonic and photonic modes. The results show that not only the pattern but also the intensity ratios of the x- and y-components of the aperture near-field match with that of the fundamental plasmonic mode. Consequently, we conclude that only the plasmonic mode reaches the tip aperture and

  13. Fiber optofluidic biosensor for the label-free detection of DNA hybridization and methylation based on an in-line tunable mode coupler.

    Science.gov (United States)

    Gao, Ran; Lu, Dan-Feng; Cheng, Jin; Jiang, Yi; Jiang, Lan; Xu, Jian-Dong; Qi, Zhi-Mei

    2016-12-15

    An optical fiber optofluidic biosensor for the detection of DNA hybridization and methylation has been proposed and experimentally demonstrated. An in-line fiber Michelson interferometer was formed in the photonic crystal fiber. A micrhole in the collapsed region, which combined the tunable mode coupler and optofluidic channel, was fabricated by using femtosecond laser micromachining. The mode field diameter of the guided light is changed with the refractive index in the optofluidic channel, which results in the tunable coupling ratio. Label-free detections of the DNA hybridization and methylation have been experimentally demonstrated. The probe single stranded DNA (ssDNA) was bound with the surface of the optofluidic channel through the Poly-l-lysine layer, and the hybridization between a short 22-mer probe ssDNA and a complementary target ssDNA was carried out and detected by interrogating the fringe visibility of the reflection spectrum. Then, the DNA methylation was also detected through the binding between the methylated DNA and the 5-methylcytosine (5-mC) monoclonal antibody. The experiments results demonstrate that the limit of detection of 5nM is achieved, establishing the tunable mode coupler as a sensitive and versatile biosensor. The sensitive optical fiber optofluidic biosensor possesses high specificity and low temperature cross-sensitivity.

  14. The dual-gain mode: a way to enhance the dynamic range of X-ray detectors

    CERN Document Server

    Matsinos, E; Kaissl, Wolfgang; Matsinos, Evangelos

    2006-01-01

    Varian Medical Systems has manufactured and recently put into operation a clinically-applicable solution for image-guided radiation therapy. Cone-beam CT imaging, one of the operation modes of the imaging unit of this device, aims at high-quality volumetric reconstruction. To boost the image quality, the dual-gain mode, a successful means for enhancing the dynamic range of the flat-panel detectors and obtaining better results in the contrast of the reconstructed image, was developed and successfully tested during the last few years. The important steps in the calibration of this mode involve a correction to the pulse widths associated with the X-ray production, the assessment of the detector signal above which nonlinear effects become significant and the determination of some properties of the detector pixels, namely, of dark fields, flatness corrections, etc. Finally, the defect-pixel map is obtained, containing dead and flickering pixels, as well as pixels with properties which are sufficiently `out of rang...

  15. Propagation of whistler-mode chorus to low altitudes: divergent ray trajectories and ground accessibility

    Directory of Open Access Journals (Sweden)

    J. Chum

    2005-12-01

    Full Text Available We investigate the ray trajectories of nonductedly propagating lower-band chorus waves with respect to their initial angle θ0, between the wave vector and ambient magnetic field. Although we consider a wide range of initial angles θ0, in order to be consistent with recent satellite observations, we pay special attention to the intervals of initial angles θ0, for which the waves propagate along the field lines in the source region, i.e. we mainly focus on waves generated with &theta0 within an interval close to 0° and on waves generated within an interval close to the Gendrin angle. We demonstrate that the ray trajectories of waves generated within an interval close to the Gendrin angle with a wave vector directed towards the lower L-shells (to the Earth significantly diverge at the frequencies typical for the lower-band chorus. Some of these diverging trajectories reach the topside ionosphere having θ close to 0°; thus, a part of the energy may leak to the ground at higher altitudes where the field lines have a nearly vertical direction. The waves generated with different initial angles are reflected. A small variation of the initial wave normal angle thus very dramatically changes the behaviour of the resulting ray. Although our approach is rather theoretical, based on the ray tracing simulation, we show that the initial angle θ0 of the waves reaching the ionosphere (possibly ground is surprisingly close - differs just by several degrees from the initial angles which fits the observation of magnetospherically reflected chorus revealed by CLUSTER satellites. We also mention observations of diverging trajectories on low altitude satellites.

  16. Hybrid Wing Body Shielding Studies Using an Ultrasonic Configurable Fan Artificial Noise Source Generating Typical Turbofan Modes

    Science.gov (United States)

    Sutliff, Daniel l.; Brown, Clifford A.; Walker, Bruce E.

    2014-01-01

    An Ultrasonic Configurable Fan Artificial Noise Source (UCFANS) was designed, built, and tested in support of the NASA Langley Research Center's 14- by 22-ft wind tunnel test of the Hybrid Wing Body (HWB) full 3-D 5.8 percent scale model. The UCFANS is a 5.8 percent rapid prototype scale model of a high-bypass turbofan engine that can generate the tonal signature of proposed engines using artificial sources (no flow). The purpose of the test was to provide an estimate of the acoustic shielding benefits possible from mounting the engine on the upper surface of an HWB aircraft using the projected signature of the engine currently proposed for the HWB. The modal structures at the rating points were generated from inlet and exhaust nacelle configurations--a flat plate model was used as the shielding surface and vertical control surfaces with correct plan form shapes were also tested to determine their additional impact on shielding. Radiated acoustic data were acquired from a traversing linear array of 13 microphones, spanning 36 in. Two planes perpendicular, and two planes parallel, to the axis of the nacelle were acquired from the array sweep. In each plane the linear array traversed four sweeps, for a total span of 168 in. acquired. The resolution of the sweep is variable, so that points closer to the model are taken at a higher resolution. Contour plots of Sound Pressure Levels, and integrated Power Levels, from nacelle alone and shielded configurations are presented in this paper; as well as the in-duct mode power levels

  17. Horizontal rays and vertical modes method for the computation of the vertical propagation of acoustic-gravity waves

    Science.gov (United States)

    Lahaye, Noé; Smith, Stefan Llewellyn

    2016-04-01

    We consider the vertical propagation of acoustic-gravity waves generated by a finite-size perturbation at the bottom, through a moving inhomogeneous atmosphere. Under the hypothesis of weak inhomogeneities in the horizontal direction, an approximate solution is obtained in terms of normal modes and horizontal rays. The problem is thus reduced to a depth-separated equation very similar to the standard Taylor-Goldstein equation, with weak dependence of the parameters on the horizontal coordinates, and to ray equations along the horizontal -- thus decreasing the computational resources needed. One advantage of this method is to retain the signal that is partially transmitted across reflecting regions that may exist due to the background wind jet, contrary to standard ray tracing that would predict pure reflexion. In addition, the limitation to an homogeneous medium along the horizontal coordinates that applies to other standard methods based on spectral integral transforms is released with the current approach. An idealized configuration is investigated, where numerical results are shown. Finally, a more general formulation in terms of approximate adiabatic spectral integral transform is presented. Implications for the computation of the propagation of Tsunami-generated acoustic-gravity waves, and more generally waves generated at the bottom of an inhomogeneous moving fluid, are discussed.

  18. A 5G Hybrid Channel Model Considering Rays and Geometric Stochastic Propagation Graph

    DEFF Research Database (Denmark)

    Steinböck, Gerhard; Karstensen, Anders; Kyösti, Pekka

    2016-01-01

    We consider a ray-tracing tool, in particular the METIS map based model for deterministic simulation of the channel impulse response. The ray-tracing tool is extended by adding a geometric stochastic propagation graph to model additional stochastic paths and the dense multipath components observed...... in measurements. The computational complexity of raytracing typically prohibits the inclusion of the dense multipath component or limits it to the early part of the impulse response. Due to computational reasons and for lack of detailed information is the description of the environment for ray-tracing often very...... simplistic, e.g. plain walls and thus neglecting the structures on the building facades, window frames, window sills, etc. Thus in measurements there are often additional components observed that are not captured by these simplistic ray-tracing implementations. In this contribution we introduce a flexible...

  19. Dual-energy X-ray micro-CT imaging of hybrid Ni/Al open-cell foam

    Science.gov (United States)

    Fíla, T.; Kumpová, I.; Koudelka, P.; Zlámal, P.; Vavřík, D.; Jiroušek, O.; Jung, A.

    2016-01-01

    In this paper, we employ dual-energy X-ray microfocus tomography (DECT) measurement to develop high-resolution finite element (FE) models that can be used for the numerical assessment of the deformation behaviour of hybrid Ni/Al foam subjected to both quasi-static and dynamic compressive loading. Cubic samples of hybrid Ni/Al open-cell foam with an edge length of [15]mm were investigated by the DECT measurement. The material was prepared using AlSi7Mg0.3 aluminium foam with a mean pore size of [0.85]mm, coated with nanocrystalline nickel (crystallite size of approx. [50]nm) to form a surface layer with a theoretical thickness of [0.075]mm. CT imaging was carried out using state-of-the-art DSCT/DECT X-ray scanner developed at Centre of Excellence Telč. The device consists of a modular orthogonal assembly of two tube-detector imaging pairs, with an independent geometry setting and shared rotational stage mounted on a complex 16-axis CNC positioning system to enable unprecedented measurement variability for highly-detailed tomographical measurements. A sample of the metal foam was simultaneously irradiated using an XWT-240-SE reflection type X-ray tube and an XWT-160-TCHR transmission type X-ray tube. An enhanced dual-source sampling strategy was used for data acquisition. X-ray images were taken using XRD1622 large area GOS scintillator flat panel detectors with an active area of [410 × 410]mm and resolution [2048 × 2048]pixels. Tomographic scanning was performed in 1,200 projections with a 0.3 degree angular step to improve the accuracy of the generated models due to the very complex microstructure and high attenuation of the investigated material. Reconstructed data was processed using a dual-energy algorithm, and was used for the development of a 3D model and voxel model of the foam. The selected parameters of the models were compared with nominal parameters of the actual foam and showed good correlation.

  20. The simulation of hard x-ray images obtained during lower hybrid current drive on PBX-M

    Energy Technology Data Exchange (ETDEWEB)

    Goeler, S. von; Fishman, H.; Ignat, D. [and others

    1994-10-01

    During lower hybrid current drive on PBX-M suprathermal electrons in the 30 to 150 keV range are generated. These electrons emit hard X-ray bremsstrahlung in collisions with plasma ions; the radiation creates images in a hard X-ray pinhole camera. In order to interpret the hard X-ray images, a computer simulation code has been written, the PBXRAY code. It represents an extension of the STEVENS code that calculates the free-free and free-bound radiation for non-Maxwellian relativistic electron tail distributions. The PBXRAY code provides the chord integration in the bean-shaped plasma geometry on PBX-M and integrates over photon energy. The simulations show that the location of the suprathermal electrons can be determined with an accuracy of approximately two centimeters in the plasma. In particular, the authors analyzed discharges whose characteristic ``hollow`` images indicate off-axis LH current drive. A comparison of images taken with different absorber foils reveals that the suprathermal electrons have less than 150 keV parallel energy for the hollow discharges.

  1. Validation of columnar CsI x-ray detector responses obtained with hybridMANTIS, a CPU-GPU Monte Carlo code for coupled x-ray, electron, and optical transport.

    Science.gov (United States)

    Sharma, Diksha; Badano, Aldo

    2013-03-01

    hybridMANTIS is a Monte Carlo package for modeling indirect x-ray imagers using columnar geometry based on a hybrid concept that maximizes the utilization of available CPU and graphics processing unit processors in a workstation. The authors compare hybridMANTIS x-ray response simulations to previously published MANTIS and experimental data for four cesium iodide scintillator screens. These screens have a variety of reflective and absorptive surfaces with different thicknesses. The authors analyze hybridMANTIS results in terms of modulation transfer function and calculate the root mean square difference and Swank factors from simulated and experimental results. The comparison suggests that hybridMANTIS better matches the experimental data as compared to MANTIS, especially at high spatial frequencies and for the thicker screens. hybridMANTIS simulations are much faster than MANTIS with speed-ups up to 5260. hybridMANTIS is a useful tool for improved description and optimization of image acquisition stages in medical imaging systems and for modeling the forward problem in iterative reconstruction algorithms.

  2. STUDY OF THE CORRELATION BETWEEN POWER DEPOSITION OFTHE LOWER HYBRID WAVES AND THE HARDX-RAY RADIATION ON HT-7 TOKAMAK

    Institute of Scientific and Technical Information of China (English)

    石跃江; 万宝年; 凌必利; 丁伯江

    2001-01-01

    A seven-channel NaI(T1) detector array installed on an HT-7 superconducting tokamak has been used to detect the hard X-ray (Ehv>20 keV) emitted from the plasma. The physical mechanism of the lower hybrid waves propagating and absorbed in the plasma is investigated by the measurement of the hard X-ray radial profile at different discharge parameters.

  3. Analysis on the Radiation Property of the Bounded Modes of Periodic Leaky-Wave Structure with Finite-Length Using a Hybrid Method.

    Science.gov (United States)

    Li, Zheng; Wang, Junhong; Duan, Jianjie; Zhang, Zhan; Chen, Meie

    2016-03-18

    In this paper the radiation property of the one-dimensional periodic leaky-wave structure is analysed using a new hybrid method, which involves the mode expansion method for expanding the periodic aperture field in terms of spatial harmonics and the method of effective radiation sections for transforming the expanded fields into far fields. Using this method, the radiation of each spatial harmonic can be achieved, and the contributions of the harmonics (especially the bounded modes) to the total radiation of the periodic leaky-wave structure can be calculated. The main findings in this paper demonstrate that the bounded modes in a finite length structure have obvious contribution to the far-field radiation, which was considered to be non-radiative and always ignored in the conventional researches.

  4. Search for Gamma Ray Bursts with the Argo-YBJ Detector in Scaler Mode

    CERN Document Server

    Aielli, G

    2009-01-01

    We report on the search for Gamma Ray Bursts (GRBs) in the energy range 1-100 GeV in coincidence with the prompt emission detected by satellites using the Astrophysical Radiation with Ground-based Observatory at YangBaJing (ARGO-YBJ) air shower detector. Thanks to its mountain location (Yangbajing, Tibet, P.R. China, 4300 m a.s.l.), active surface (about 6700 m**2 of Resistive Plate Chambers), and large field of view (about 2 sr, limited only by the atmospheric absorption), the ARGO-YBJ air shower detector is particularly suitable for the detection of unpredictable and short duration events such as GRBs. The search is carried out using the "single particle technique", i.e. counting all the particles hitting the detector without measurement of the energy and arrival direction of the primary gamma rays. Between 2004 December 17 and 2009 April 7, 81 GRBs detected by satellites occurred within the field of view of ARGO-YBJ (zenith angle 1 GeV counterpart in the ARGO-YBJ data finding no statistically significant e...

  5. X-ray imaging with photon counting hybrid semiconductor pixel detectors

    CERN Document Server

    Manolopoulos, S; Campbell, M; Snoeys, W; Heijne, Erik H M; Pernigotti, E; Raine, C; Smith, K; Watt, J; O'Shea, V; Ludwig, J; Schwarz, C

    1999-01-01

    Semiconductor pixel detectors, originally developed for particle physics experiments, have been studied as X-ray imaging devices. The performance of devices using the OMEGA 3 read-out chip bump-bonded to pixellated silicon semiconductor detectors is characterised in terms of their signal-to-noise ratio when exposed to 60 kVp X-rays. Although parts of the devices achieve values of this ratio compatible with the noise being photon statistics limited, this is not found to hold for the whole pixel matrix, resulting in the global signal-to-noise ratio being compromised. First results are presented of X-ray images taken with a gallium arsenide pixel detector bump-bonded to a new read-out chip, (MEDIPIX), which is a single photon counting read-out chip incorporating a 15-bit counter in every pixel. (author)

  6. X-ray imaging with photon counting hybrid semiconductor pixel detectors

    Energy Technology Data Exchange (ETDEWEB)

    Manolopoulos, S.; Bates, R.; Campbell, M.; Snoeys, W.; Heijne, E.; Pernigotti, E.; Raine, C.; Smith, K. E-mail: k.smith@physics.gla.ac.uk; Watt, J.; O' Shea, V.; Ludwig, J.; Schwarz, C

    1999-09-11

    Semiconductor pixel detectors, originally developed for particle physics experiments, have been studied as X-ray imaging devices. The performance of devices using the {omega}3 read-out chip bump-bonded to pixellated silicon semiconductor detectors is characterised in terms of their signal-to-noise ratio when exposed to 60 kVp X-rays. Although parts of the devices achieve values of this ratio compatible with the noise being photon statistics limited, this is not found to hold for the whole pixel matrix, resulting in the global signal-to-noise ratio being compromised. First results are presented of X-ray images taken with a gallium arsenide pixel detector bump-bonded to a new read-out chip, (MEDIPIX), which is a single photon counting read-out chip incorporating a 15-bit counter in every pixel. (author)

  7. Transient Oscillations Analysis and Modified Control Strategy for Seamless Mode Transfer in Micro-Grids: A Wind-PV-ES Hybrid System Case Study

    Directory of Open Access Journals (Sweden)

    Tengfei Zhang

    2015-12-01

    Full Text Available With the rapid development of the micro-grid associated with new and clean energies, the smooth switching between grid-connected and islanded operation modes of the micro-grid is a key issue that needs to be addressed urgently. In traditional solutions, V/f (Voltage/frequency control is adopted for the master micro sources when the micro-grid works in islanded mode, while PQ (real and reactive power control is adopted when in grid-connected mode. However, when the two controllers switch when mode transfer occurs, transient oscillations usually occur and thereafter the dynamic response will be degraded. This paper considers an archetypical micro-grid with Wind-PV-ES (Wind, Photovoltaic and Energy Storage hybrid system, which forms the basis of our case study. The underlying reason for such transient oscillation is analyzed in this paper. Thereafter a modified control strategy for seamless mode transfer is designed and implemented. An improved PQ control method is designed by which the output of the PQ controller always synchronously tracks the output of the V/f controller for micro-grid switches from islanded mode to grid-connected; furthermore, a dq rotating coordinate synchronization based V/f control method is proposed for transition from grid-connected mode to islanded mode. Finally, experiments and analysis are undertaken on some basic and important operating cases; the results in our case study indicate that the modified control strategy is effective in dominating the micro-grid during mode transfer and thus yielding significantly better performances.

  8. Conformational restriction approach to β-secretase (BACE1) inhibitors III: effective investigation of the binding mode by combinational use of X-ray analysis, isothermal titration calorimetry and theoretical calculations.

    Science.gov (United States)

    Yonezawa, Shuji; Fujiwara, Kenichiro; Yamamoto, Takahiko; Hattori, Kazunari; Yamakawa, Hidekuni; Muto, Chie; Hosono, Motoko; Tanaka, Yoshikazu; Nakano, Toru; Takemoto, Hiroshi; Arisawa, Mitsuhiro; Shuto, Satoshi

    2013-11-01

    For further investigation of BACE1 inhibitors using conformational restriction with sp(3) hybridized carbon, we applied this approach to 6-substituted aminopyrimidone derivatives 3 to improve the inhibitory activity by reducing the entropic energy loss upon binding to BACE1. Among eight stereoisomers synthesized, [trans-(1'R,2'R),6S] isomer 6 exhibited the best BACE1 inhibitory activity, which was statistically superior to that of the corresponding ethylene linker compound (R)-3. Combinational examinations of the binding mode of 6 were performed, which included isothermal titration calorimetry (ITC), X-ray crystallographic structure analysis and theoretical calculations, to clarify the effect of our conformational restriction approach. From the ITC measurement, the binding entropy of 6 was found to be ∼0.5kcal larger than that of (R)-3, which is considered to be affected by conformational restriction with a cyclopropane ring.

  9. Influence of hybridization in the magnetic circular X-ray dichroism at the Ce-M(4,5) absorption edges of Ce-Fe systems

    NARCIS (Netherlands)

    Finazzi, M; deGroot, FMF; Dias, AM; Kappler, JP; Schulte, O; Felsch, W; Krill, G

    We have performed a Magnetic Circular X-ray Dichroism (XMCD) study at the Ce-M(4,5) absorption edges on some Ce-Fe systems. We find that the dichroism signal in these systems is very sensitive to the degree of hybridization of the 4f electrons with the valence band. XMCD is able to demonstrate that

  10. Influence of hybridization in the Magnetic Circular X-ray Dichroism at the Ce-M4,5 absorption edges of Ce-Fe systems

    NARCIS (Netherlands)

    Finazzi, M.; de Groot, F.M.F.; Dias, A.-M.; Kappler, J.-P.; Schulte, O.; Felsch, W.; Krill, G.

    2013-01-01

    We have performed a Magnetic Circular X-ray Dichroism (XMCD) study at the Ce-M*,s absorption edges on some Ce-Fe systems. We find that the dichroism signal in these systems is very sensitive to the degree of hybridization of the 4f electrons with the valence band. XMCD is able to demonstrate that th

  11. Influence of hybridization in the magnetic circular X-ray dichroism at the Ce-M(4,5) absorption edges of Ce-Fe systems

    NARCIS (Netherlands)

    Finazzi, M; deGroot, FMF; Dias, AM; Kappler, JP; Schulte, O; Felsch, W; Krill, G

    1996-01-01

    We have performed a Magnetic Circular X-ray Dichroism (XMCD) study at the Ce-M(4,5) absorption edges on some Ce-Fe systems. We find that the dichroism signal in these systems is very sensitive to the degree of hybridization of the 4f electrons with the valence band. XMCD is able to demonstrate that

  12. Phonons and hybrid modes in the high and low temperature far infrared dynamics of hexagonal TmMnO3.

    Science.gov (United States)

    Massa, Néstor E; del Campo, Leire; De Sousa Meneses, Domingos; Echegut, Patrick; Martínez-Lope, María Jesús; Alonso, José Antonio

    2014-07-01

    We report on temperature dependent TmMnO3 far infrared emissivity and reflectivity spectra from 1910 K to 4 K. At the highest temperature the number of infrared bands is lower than that predicted for centrosymmetric P63/mmc (D(4)(6h)) (Z = 2) space group due to high temperature anharmonicity and possible defect induced bitetrahedra misalignments. On cooling, at ~1600 ± 40 K, TmMnO3 goes from non-polar to an antiferroelectric-ferroelectric polar phase reaching the ferroelectric onset at ~700 K. Room temperature reflectivity is fitted using 19 oscillators and this number of phonons is maintained down to 4 K. A weak phonon anomaly in the band profile at 217 cm(-1) (4 K) suggests subtle Rare Earth magneto-electric couplings at ~TN and below. A low energy collective excitation is identified as a THz instability associated with room temperature eg electrons in a d-orbital fluctuating environment. It condenses into two modes that emerge pinned to the E-type antiferromagnetic order hardening simultaneously down to 4 K. They obey power laws with TN as the critical temperature and match known zone center magnons. The one peaking at 26 cm(-1), with critical exponent β=0.42 as for antiferromagnetic order in a hexagonal lattice, is dependent on the Rare Earth ion. The higher frequency companion at ~50 cm(-1), with β=0.25, splits at ~TN into two peaks. The weaker band of the two is assimilated to the upper branch of the gap opening in the transverse acoustical (TA) phonon branch crossing the magnetic dispersion found in YMnO3. (Petit et al 2007 Phys. Rev. Lett. 99 266604). The stronger second band at ~36 cm(-1) corresponds to the lower branch of the TA gap. We assign both excitations as zone center magneto-electric hybrid quasiparticles, concluding that in NdMnO3 perovskite the equivalent picture corresponds to an instability which may be driven by an external field to transform NdMnO3 into a multiferroic compound by perturbation enhancing the TA

  13. Evaluation of a photon-counting hybrid pixel detector array with a synchrotron X-ray source

    CERN Document Server

    Ponchut, C; Fornaini, A; Graafsma, H; Maiorino, M; Mettivier, G; Calvet, D

    2002-01-01

    A photon-counting hybrid pixel detector (Medipix-1) has been characterized using a synchrotron X-ray source. The detector consists of a readout ASIC with 64x64 independent photon-counting cells of 170x170 mu m sup 2 pitch, bump-bonded to a 300 mu m thick silicon sensor, read out by a PCIbus-based electronics, and a graphical user interface (GUI) software. The intensity and the energy tunability of the X-ray source allow characterization of the detector in the time, space, and energy domains. The system can be read out on external trigger at a frame rate of 100 Hz with 3 ms exposure time per frame. The detector response is tested up to more than 7x10 sup 5 detected events/pixel/s. The point-spread response shows <2% crosstalk between neighboring pixels. Fine scanning of the detector surface with a 10 mu m beam reveals no loss in sensitivity between adjacent pixels as could result from charge sharing in the silicon sensor. Photons down to 6 keV can be detected after equalization of the thresholds of individu...

  14. X-ray Pulsars Across the Parameter Space of Luminosity, Accretion Mode, and Spin

    Science.gov (United States)

    Laycock, Silas; Yang, Jun; Christodoulou, Dimitris; Coe, Malcolm; Cappallo, Rigel; Zezas, Andreas; Ho, Wynn C. G.; Hong, JaeSub; Fingerman, Samuel; Drake, Jeremy J.; Kretschmar, Peter; Antoniou, Vallia

    2017-08-01

    We present our multi-satellite library of X-ray Pulsar observations to the community, and highlight recent science results. Available at www.xraypulsars.space the library provides a range of high-level data products, including: activity histories, pulse-profiles, phased event files, and a unique pulse-profile modeling interface. The initial release (v1.0) contains some 15 years of RXTE-PCA, Chandra ACIS-I, and XMM-PN observations of the Small Magellanic Cloud, creating a valuable record of pulsar behavior. Our library is intended to enable new progress on fundamental NS parameters and accretion physics. The major motivations are (1) Assemble a large homogeneous sample to enable population statistics. This has so far been used to map the propeller transition, and explore the role of retrograde and pro-grade accretion disks. (2) Obtain pulse-profiles for the same pulsars on many different occasions, at different luminosities and states in order to break model degeneracies. This effort has led to preliminary measurements of the offsets between magnetic and spin axes. With the addition of other satellites, and Galactic pulsars, the library will cover the entire available range of luminosity, variability timescales and accretion regimes.

  15. X-ray imaging with scintillator-sensitized hybrid organic photodetectors

    Science.gov (United States)

    Büchele, Patric; Richter, Moses; Tedde, Sandro F.; Matt, Gebhard J.; Ankah, Genesis N.; Fischer, Rene; Biele, Markus; Metzger, Wilhelm; Lilliu, Samuele; Bikondoa, Oier; MacDonald, J. Emyr; Brabec, Christoph J.; Kraus, Tobias; Lemmer, Uli; Schmidt, Oliver

    2015-12-01

    Medical X-ray imaging requires cost-effective and high-resolution flat-panel detectors for the energy range between 20 and 120 keV. Solution-processed photodetectors provide the opportunity to fabricate detectors with a large active area at low cost. Here, we present a disruptive approach that improves the resolution of such detectors by incorporating terbium-doped gadolinium oxysulfide scintillator particles into an organic photodetector matrix. The X-ray induced light emission from the scintillators is absorbed within hundreds of nanometres, which is negligible compared with the pixel size. Hence, optical crosstalk, a limiting factor in the resolution of scintillator-based X-ray detectors, is minimized. The concept is validated with a 256 × 256 pixel detector with a resolution of 4.75 lp mm-1 at a MTF = 0.2, significantly better than previous stacked scintillator-based flat-panel detectors. We achieved a resolution that proves the feasibility of solution-based detectors in medical applications. Time-resolved electrical characterization showed enhanced charge carrier mobility with increased scintillator filling, which is explained by morphological changes.

  16. OPTIMIZATION ABOUT COMBINED HYBRID SCHEME WITH 5-PARAMETER STRESS MODE%5参数应力组合杂交格式优化

    Institute of Scientific and Technical Information of China (English)

    聂玉峰; 尹云辉; 周天孝

    2004-01-01

    It is posed in paper [1] that Zero energy-error can be used to realize the optimization of Combined hybrid finite element methods through adjusting the combined factor. In this paper, the optimization method is used to plane 4-node quadrilateral Combined hybrid scheme CH(0-1) which own 5 stress parameters with energy compatibility characteristic. Based on the optimization results, the analysis of components of element stiffness matrix, and the conclusions about numerical stability and convergence, this paper deduces that the optimal form of CH(0-1) element, is let the combined factor take 1, i.e., just base on Hellinger-Reissner variational principle, and take bilinear compatible displacement interpolation instead of enrich-strain Wilson's displacements interpolation for the orthgonality of 5-parameter stresses mode with the derived strain from Wilson bubble displacements and the weak force balance.

  17. Revealing the synergetic effects in Ni nanoparticle-carbon nanotube hybrids by scanning transmission X-ray microscopy and their application in the hydrolysis of ammonia borane

    Science.gov (United States)

    Zhao, Guanqi; Zhong, Jun; Wang, Jian; Sham, Tsun-Kong; Sun, Xuhui; Lee, Shuit-Tong

    2015-05-01

    The hybrids of carbon nanotubes (CNTs) and the supported Ni nanoparticles (NPs) have been studied by scanning transmission X-ray microscopy (STXM) and tested by the hydrolysis reaction of ammonia borane (AB, NH3BH3). Data clearly showed the existence of a strong interaction between Ni NPs and thin CNTs (C-O-Ni bonds), which favored the tunable (buffer) electronic structure of Ni NPs facilitating the catalytic process. The hydrolysis process of AB confirmed the hypothesis that the hybrids with a strong interfacial interaction would show superior catalytic performance, while the hybrids with a weak interfacial interaction show poor performance. Our results provide a wealth of detailed information regarding the electronic structure of the NP-CNT hybrids and provide guidance towards the rational design of high-performance catalysts for energy applications.The hybrids of carbon nanotubes (CNTs) and the supported Ni nanoparticles (NPs) have been studied by scanning transmission X-ray microscopy (STXM) and tested by the hydrolysis reaction of ammonia borane (AB, NH3BH3). Data clearly showed the existence of a strong interaction between Ni NPs and thin CNTs (C-O-Ni bonds), which favored the tunable (buffer) electronic structure of Ni NPs facilitating the catalytic process. The hydrolysis process of AB confirmed the hypothesis that the hybrids with a strong interfacial interaction would show superior catalytic performance, while the hybrids with a weak interfacial interaction show poor performance. Our results provide a wealth of detailed information regarding the electronic structure of the NP-CNT hybrids and provide guidance towards the rational design of high-performance catalysts for energy applications. Electronic supplementary information (ESI) available: Magnified TEM images, high resolution TEM images and the particle size distributions of the samples, the STXM results of a thick tube at different positions, XPS results, stability test. See DOI: 10.1039/c5nr01168j

  18. Ultrafast X-ray diffraction probe of terahertz field-driven soft mode dynamics in SrTiO 3

    Energy Technology Data Exchange (ETDEWEB)

    Kozina, M.; Driel, T.van; Chollet, M.; Sato, T.; Glownia, J.M.; Wandel, S.; /SLAC; Radovic, M.; /PSI, SLS /PSI, Villigen; Staub, U.; /PSI, Villigen; Hoffmann, M.C.; /SLAC

    2017-09-01

    We use ultrafast X-ray pulses to characterize the lattice response of SrTiO3 when driven by strong terahertz fields. We observe transient changes in the diffraction intensity with a delayed onset with respect to the driving field. Fourier analysis reveals two frequency components corresponding to the two lowest energy zone-center optical modes in SrTiO3. The lower frequency mode exhibits clear softening as the temperature is decreased while the higher frequency mode shows slight temperature dependence.

  19. Two Distinct Modes of Hydrogen-Bonding Interaction in the Prototypic Hybrid Halide Perovskite, Tetragonal CH3NH3PbI3

    OpenAIRE

    Lee, June Ho; Lee, Jung-Hoon; Kong, Eui-Hyun; Jang, Hyun M.

    2015-01-01

    In spite of the key role of hydrogen bonding in the structural stabilization of the prototypic hybrid halide perovskite, CH3NH3PbI3 (MAPbI3), little progress has been made in our in-depth understanding of the hydrogen-bonding interaction between the MA+-ion and the iodide ions in the PbI6-octahedron network. Herein, we show that there exist two distinct types of the hydrogen-bonding interaction, naming a- and b-modes, in the tetragonal MAPbI3 on the basis of symmetry argument and density-func...

  20. Generation of ultrashort pulses with minimum duration of 90\\ {\\text{fs}} in a hybrid mode-locked erbium-doped all-fibre ring laser

    Science.gov (United States)

    Dvoretskiy, D. A.; Sazonkin, S. G.; Voropaev, V. S.; Negin, M. A.; Leonov, S. O.; Pnev, A. B.; Karasik, V. E.; Denisov, L. K.; Krylov, A. A.; Davydov, V. A.; Obraztsova, E. D.

    2016-11-01

    Regimes of ultrashort pulse generation in an erbium-doped all-fibre ring laser with hybrid mode locking based on single-wall carbon - boron nitride nanotubes and the nonlinear Kerr effect in fibre waveguides are studied. Stable dechirped ultrashort pulses are obtained with a duration of ˜ 90 {\\text{fs}}, a repetition rate of ˜ 42.2 {\\text{MHz}}, and an average output power of ˜ 16.7 {\\text{mW}}, which corresponds to a pulse energy of ˜ 0.4 {\\text{nJ}} and a peak laser power of ˜ 4.4 {\\text{kW}}.

  1. Observer-based higher order sliding mode control of power factor in three-phase AC/DC converter for hybrid electric vehicle applications

    Science.gov (United States)

    Liu, Jianxing; Laghrouche, Salah; Wack, Maxime

    2014-06-01

    In this paper, a full-bridge boost power converter topology is studied for power factor control, using output higher order sliding mode control. The AC/DC converters are used for charging the battery and super-capacitor in hybrid electric vehicles from the utility. The proposed control forces the input currents to track the desired values, which can control the output voltage while keeping the power factor close to one. Super-twisting sliding mode observer is employed to estimate the input currents and load resistance only from the measurement of output voltage. Lyapunov analysis shows the asymptotic convergence of the closed-loop system to zero. Multi-rate simulation illustrates the effectiveness and robustness of the proposed controller in the presence of measurement noise.

  2. Majorana modes in InSb nanowires (I): zero bias peaks in hybrid devices with low-disorder and hard induced superconducting gap

    Science.gov (United States)

    Gül, Ö.; Zhang, H.; de Moor, M. W. A.; de Vries, F.; van Veen, J.; van Woerkom, D. J.; Zuo, K.; Mourik, V.; Cassidy, M.; Geresdi, A.; Car, D.; Bakkers, E. P. A. M.; Goswami, S.; Watanabe, K.; Taniguchi, T.; Kouwenhoven, L. P.

    Majorana modes in hybrid superconductor-semiconductor nanowire devices can be probed via tunnelling spectroscopy which shows a zero bias peak (ZBP) in differential conductance (1). However, alternative mechanisms such as disorder or formation of quantum dots can also give rise to ZBPs, and obscure experimental studies of Majoranas. Further, a soft induced superconducting gap commonly observed in experiments presents an outstanding challenge for the demonstration of their topological protection. In this talk we show that with device improvements, we reach low-disorder transport regime with clear quantized conductance plateaus and Andreev enhancement approaching the theoretical limit. Tunnelling spectroscopy shows a hard induced superconducting gap and no formation of quantum dots. Together with extremely stable ZBPs observed in large gate voltage and magnetic field ranges, we exclude various alternative theories besides the formation of localized Majorana modes for our observations.

  3. Investigation of the mechanical properties and failure modes of hybrid natural fiber composites for potential bone fracture fixation plates.

    Science.gov (United States)

    Manteghi, Saeed; Mahboob, Zia; Fawaz, Zouheir; Bougherara, Habiba

    2017-01-01

    The purpose of this study is to investigate the mechanical feasibility of a hybrid Glass/Flax/Epoxy composite material for bone fracture fixation such as fracture plates. These hybrid composite plates have a sandwich structure in which the outer layers are made of Glass/Epoxy and the core from Flax/Epoxy. This configuration resulted in a unique structure compared to prior composites proposed for similar clinical applications. In order to evaluate the mechanical properties of this hybrid composite, uniaxial tension, compression, three-point bending and Rockwell Hardness tests were conducted. In addition, water absorption tests were performed to investigate the rate of water absorption for the specimens. This study confirms that the proposed hybrid composite plates are significantly more flexible axially compared to conventional metallic plates. Furthermore, they have considerably higher ultimate strength in tension, compression and flexion. Such high strength will ensure good stability of bone-implant construct at the fracture site, immobilize adjacent bone fragments and carry clinical-type forces experienced during daily normal activities. Moreover, this sandwich structure with stronger and stiffer face sheets and more flexible core can result in a higher stiffness and strength in bending compared to tension and compression. These qualities make the proposed hybrid composite an ideal candidate for the design of an optimized fracture fixation system with much closer mechanical properties to human cortical bone.

  4. The Auger Engineering Radio Array and multi-hybrid cosmic ray detection

    Science.gov (United States)

    Holt, E. M.; Pierre Auger Collaboration

    2016-05-01

    The Auger Engineering Radio Array (AERA) aims at the detection of air showers induced by high-energy cosmic rays. As an extension of the Pierre Auger Observatory, it measures complementary information to the particle detectors, fluorescence telescopes and to the muon scintillators of the Auger Muons and Infill for the Ground Array (AMIGA). AERA is sensitive to all fundamental parameters of an extensive air shower such as the arrival direction, energy and depth of shower maximum. Since the radio emission is induced purely by the electromagnetic component of the shower, in combination with the AMIGA muon counters, AERA is perfect for separate measurements of the electrons and muons in the shower, if combined with a muon counting detector like AMIGA. In addition to the depth of the shower maximum, the ratio of the electron and muon number serves as a measure of the primary particle mass.

  5. Histidine-modified organic-silica hybrid monolithic column for mixed-mode per aqueous and ion-exchange capillary electrochromatography.

    Science.gov (United States)

    Tang, Sheng; Liu, Shujuan; Liang, Xiaojing; Tang, Xiaofen; Wu, Xingcai; Guo, Yong; Liu, Xia; Jiang, Shengxiang

    2015-06-01

    A novel organic-silica hybrid monolith was prepared through the binding of histidine onto the surface of monolithic matrix for mixed-mode per aqueous and ion-exchange capillary electrochromatography. The imidazolium and amino groups on the surface of the monolithic stationary phase were used to generate an anodic electro-osmotic flow as well as to provide electrostatic interaction sites for the charged compounds at low pH. Typical per aqueous chromatographic behavior was observed in water-rich mobile phases. Various polar and hydrophilic analytes were selected to evaluate the characteristics and chromatographic performance of the obtained monolith. Under per aqueous conditions, the mixed-mode mechanism of hydrophobic and ion-exchange interactions was observed and the resultant monolithic column proved to be very versatile for the efficient separations of these polar and hydrophilic compounds (including amides, nucleosides and nucleotide bases, benzoic acid derivatives, and amino acids) in highly aqueous mobile phases. The successful applications suggested that the histidine-modified organic-silica hybrid monolithic column could offer a wide range of retention behaviors and flexible selectivities toward polar and hydrophilic compounds.

  6. Detective Quantum Efficiency of a CsI-CMOS X-ray Detector for Breast Tomosynthesis Operating in High Dynamic Range and High Sensitivity Modes.

    Science.gov (United States)

    Patel, Tushita; Klanian, Kelly; Gong, Zongyi; Williams, Mark B

    2012-07-01

    The spatial frequency dependent detective quantum efficiency (DQE) of a CsI-CMOS x-ray detector was measured in two operating modes: a high dynamic range (HDR) mode and a high sensitivity (HS) mode. DQE calculations were performed using the IEC-62220-1-2 Standard. For detector entrance air kerma values between ~7 µGy and 60 µGy the DQE is similar in either HDR mode or HS mode, with a value of ~0.7 at low frequency and ~ 0.15 - 0.20 at the Nyquist frequency fN = 6.7 mm(-1). In HDR mode the DQE remains virtually constant for operation with Ka values between ~7 µGy and 119 µGy but decreases for Ka levels below ~ 7 µGy. In HS mode the DQE is approximately constant over the full range of entrance air kerma tested between 1.7 µGy and 60 µGy but kerma values above ~75 µGy produce hard saturation. Quantum limited operation in HS mode for entrance kerma as small as 1.7 µGy makes it possible to use a large number of low dose views to improve angular sampling and decrease acquisition time.

  7. Pneumatic-Combustion Hybrid Engine: A Study of the Effect of the Valvetrain Sophistication on Pneumatic Modes Moteur hybride pneumatique: une étude de l’effet de la complexité de la distribution sur les modes pneumatiques

    OpenAIRE

    Brejaud P.; Charlet A.; Chamaillard Y.; Ivanco A.; Higelin P.

    2009-01-01

    Although internal combustion engines display high overall maximum global efficiencies, this potential cannot be fully exploited in automotive applications: in real conditions, the average engine load (and thus efficiency) is quite low and the kinetic energy during a braking phase is lost. This work presents a hybrid pneumatic-combustion engine and the associated thermodynamic cycles, which is able to store and recover energy in the form of compressed air. The study focuses on the two maj...

  8. The first examples of 1-D organic hybrid lanthanoid thioarsenates based on two [As(V)S4](3-) linkage modes.

    Science.gov (United States)

    Zhao, Rong-Qing; Liu, Xing; Zhou, Jian; Xiao, Hong-Ping; Zou, Hua-Hong; Fu, Lianshe; Tang, Qiuling; Tan, Xiao-Feng

    2016-04-14

    A series of new 1-D organic hybrid lanthanoid thioarsenates [Ln(dap)2]2(μ-η(1):η(1):η(1):η(1)-AsS4)(μ-η(1):η(1)-As(V)S4)]n {Ln = Ce (Ia), Pr (Ib), Nd (Ic), and Sm (Id); dap = diaminopropane} have been prepared under solvothermal conditions and structurally characterized. Compounds Ia-d contain two [As(V)S4](3-) linkage modes, namely μ-η(1):η(1):η(1):η(1)-As(V)S4 and μ-η(1):η(1)-As(V)S4, which are linked alternately with [Ln(dap)2](3+) groups into 1-D neutral chains [Ln(dap)2]2(μ-η(1):η(1):η(1):η(1)-As(V)S4)(μ-η(1):η(1)-As(V)S4)]n, which represent the first examples of 1-D organic hybrid lanthanoid thioarsenates based on two [As(V)S4](3-) linkage modes. To learn more about the influence of lanthanide contraction on the formation of lanthanoid thioarsenates, five organic hybrid lanthanoid thioarsenates [Ln(dap)3As(V)S4] [Ln = Tb (IIa), Dy (IIb), Ho (IIIc), and Er (IIId)] and [Er(dien)2As(V)S4] (III, dien = diethylenetriamine) are also provided. Both II and III contain neutral lanthanide-centred complexes, where the tetrahedral anion [As(V)S4](3-) acts as a chelating ligand to the complex [Ln(dap)3](3+)/[Er(dien)2](3+) cation. Their optical properties have been characterized by UV-vis spectra, and the density functional theory calculation of Ia has been performed.

  9. Quantitative fluorescent in-situ hybridization: a hypothesized competition mode between two dominant bacteria groups in hydrogen-producing anaerobic sludge processes.

    Science.gov (United States)

    Huang, C-L; Chen, C-C; Lin, C-Y; Liu, W-T

    2009-01-01

    Two hydrogen-producing continuous flow stirred tank reactors (CSTRs) fed respectively with glucose and sucrose were investigated by polymerase chain reaction-denatured gradient gel electrophoresis (PCR-DGGE) and fluorescent in-situ hybridization (FISH). The substrate was fed in a continuous mode decreased from hydraulic retention time (HRT) 10 hours to 6, 5, 4, 3, and 2 hours. Quantitative fluorescent in-situ hybridization (FISH) observations further demonstrated that two morphotypes of bacteria dominated both microbial communities. One was long rod bacteria which can be targeted either by Chis150 probe designed to hybridize the gram positive low G + C bacteria or the specific oligonucleotide probe Lg10-6. The probe Lg10-6, affiliated with Clostridium pasteurianum, was designed and then checked with other reference organisms. The other type, unknown group, which cannot be detected by Chis150 was curved rod bacteria. Notably, the population ratios of the two predominant groups reflected the different operational performance of the two reactors, such as hydrogen producing rates, substrate turnover rates and metabolites compositions. Therefore, a competition mode of the two dominant bacteria groups was hypothesized. In the study, 16S rRNA-based gene library of hydrogen-producing microbial communities was established. The efficiency of hydrogen yields was correlated with substrates (glucose or sucrose), HRT, metabolites compositions (acetate, propionate, butyrate and ethanol), thermal pre-treatment (seed biomass was heated at 100 degrees C for 45 minutes), and microbial communities in the bioreactor, not sludge sources (municipal sewage sludge, alcohol-processing sludge, or bean-processing sludge). The designed specific oligonucleotide probe Lg10-6 also provides us a useful and fast molecular tool to screen hydrogen-producing microbial communities in the future research.

  10. Performance of hybrid angle-energy dispersive X-ray diffraction and fluorescence portable system for non-invasive surface-mineral identification in Archaeometry

    CERN Document Server

    Cuevas, Ariadna Mendoza

    2016-01-01

    Low power energy dispersive XRD-XRF portable instruments equipped with multiple angle scanning can take advantage of the shorter acquisition time of EDXRD with respect to ADXRD, and bring closer higher accuracy and resolution of inter-planar distance with those obtained by ADXRD. The data produced by this new hybrid configuration is correlated in the sense that a single XRF or XRD specimen appear in multiple spectra (the later shifted in energy for differing angles). Hence, for fully benefit from the richer data released by this configuration, the analysis should not be confined to the independent processing of the spectra, specialized hybrid data processing should be conceived. We previously reported some advances in the processing of the resulting 3D data (intensity, energy and angle). Here the analytical performance of the first hybrid angle-energy dispersive X-ray diffraction and fluorescence portable system is assessed for non-invasive surface mineral analysis of samples relevant for archaeometrical appl...

  11. Silage production and quality of pearl millet, sorghum, and corn hybrids grown from seed exposed to low doses of gamma rays

    Energy Technology Data Exchange (ETDEWEB)

    Burton, G.W.; Monson, W.G.; Hanna, W.W.; Constantin, M.J.

    1975-01-01

    Just before planting, seeds of pearl millet, Pennisetum americanum (L.) K. Schum., (formerly P. typhoides) hybrid, ''Tift 23 x L/sub 1/,'' and corn, Zea mays L., hybrids ''Coker 71,'' ''DeKalb 1214,'' and ''Pioneer 3030'' were exposed to ..gamma.. ray dosages of 0, 0.15, 0.3, 0.6, 1.2, 2.4, 4.8, 9.6, and 19.2 kR. ''FS26'' hybrid sorghum, Sorghum bicolor (L.) Moench., seeds were exposed to ..gamma.. ray dosages of 0, 0.2, 0.4, 0.8, 1.6, 3.2, 6.4, 12.8, and 25.6 kR. In one 2-yr. experiment, pearl millet, sorghum, and Coker 71 corn gave respective dry matter yields of 12, 166, 6,993, and 6,306 kg/ha and in vitro dry matter digestibility (IVDMD) percentages of 45.7, 52.8, and 59.9. The heaviest exposures of ..gamma.. rays generally reduced yields of all species, and lighter exposures failed to increase yield significantly. Seed irradiation did not affect the quality (IVDMD) of the forage. In a 2-yr. corn hybrid experiment, DeKalb 1214 yielded 24 percent more dry matter and tolerated the heavy exposures of ..gamma.. rays better than Pioneer 3030 and Coker 71. None of the lower exposures increased yield significantly. (auth)

  12. Modal–Physical Hybrid System Identification of High-rise Building via Subspace and Inverse-Mode Methods

    Directory of Open Access Journals (Sweden)

    Kohei Fujita

    2017-08-01

    Full Text Available A system identification (SI problem of high-rise buildings is investigated under restricted data environments. The shear and bending stiffnesses of a shear-bending model (SB model representing the high-rise buildings are identified via the smart combination of the subspace and inverse-mode methods. Since the shear and bending stiffnesses of the SB model can be identified in the inverse-mode method by using the lowest mode of horizontal displacements and floor rotation angles, the lowest mode of the objective building is identified first by using the subspace method. Identification of the lowest mode is performed by using the amplitude of transfer functions derived in the subspace method. Considering the resolution in measuring the floor rotation angles in lower stories, floor rotation angles in most stories are predicted from the floor rotation angle at the top floor. An empirical equation of floor rotation angles is proposed by investigating those for various building models. From the viewpoint of application of the present SI method to practical situations, a non-simultaneous measurement system is also proposed. In order to investigate the reliability and accuracy of the proposed SI method, a 10-story building frame subjected to micro-tremor is examined.

  13. Pre-treatment patient-specific stopping power by combining list-mode proton radiography and x-ray CT

    Science.gov (United States)

    Collins-Fekete, Charles-Antoine; Brousmiche, Sébastien; Hansen, David C.; Beaulieu, Luc; Seco, Joao

    2017-09-01

    The relative stopping power (RSP) uncertainty is the largest contributor to the range uncertainty in proton therapy. The purpose of this work was to develop a systematic method that yields accurate and patient-specific RSPs by combining (1) pre-treatment x-ray CT and (2) daily proton radiography of the patient. The method was formulated as a penalized least squares optimization problem (argmin(\\Vert {A}{x}-{b}\\Vert _22 )). The parameter A represents the cumulative path-length crossed by the proton in each material, separated by thresholding on the HU. The material RSPs (water equivalent thickness/physical thickness) are denoted by x. The parameter b is the list-mode proton radiography produced using Geant4 simulations. The problem was solved using a non-negative linear-solver with {x}≥slant0 . A was computed by superposing proton trajectories calculated with a cubic or linear spline approach to the CT. The material’s RSP assigned in Geant4 were used for reference while the clinical HU-RSP calibration curve was used for comparison. The Gammex RMI-467 phantom was first investigated. The standard deviation between the estimated material RSP and the calculated RSP is 0.45%. The robustness of the techniques was then assessed as a function of the number of projections and initial proton energy. Optimization with two initial projections yields precise RSP (⩽1.0%) for 330 MeV protons. 250 MeV protons have shown higher uncertainty (⩽2.0%) due to the loss of precision in the path estimate. Anthropomorphic phantoms of the head, pelvis, and lung were subsequently evaluated. Accurate RSP has been obtained for the head (μ =0.21+/-1.63% ), the lung (μ=0.06+/-0.99% ) and the pelvis (μ=0.90+/-3.87% ). The range precision has been optimized using the calibration curves obtained with the algorithm, yielding a mean R80 difference to the reference of 0.11  ±0.09%, 0.28  ±  0.34% and 0.05 +/- 0.06% in the same order. The solution’s accuracy is limited by the

  14. Hybrid magneto-optical mode converter made with a magnetic nanoparticles-doped SiO2/ZrO2 layer coated on an ion-exchanged glass waveguide

    Science.gov (United States)

    Amata, Hadi; Royer, François; Choueikani, Fadi; Jamon, Damien; Parsy, François; Broquin, Jean-Emmanuel; Neveu, Sophie; Jacques Rousseau, Jean

    2011-12-01

    This paper describes the possibility to achieve a TE-TM mode conversion in a magneto-optical hybrid waveguide operating at λ = 1550 nm. This hybrid device is made by coating a SiO2/ZrO2 layer doped with magnetic nanoparticles on an ion-exchanged glass waveguide. Soft annealing (90 °C) and UV treatment, both compatible with the ion exchange process, have been implemented to finalize the magneto-optical film. Optical characterizations that have been carried out demonstrated the efficiency of these hybrid structures in terms of lateral confinement and mode conversion. Indeed, TE to TM mode conversion has been observed when a longitudinal magnetic field is applied to the device. The amount of this conversion is discussed taking into account the distribution of light between the layer and the guide, and the modal birefringence of the structure.

  15. Multiple-bunch-length operating mode design for a storage ring using hybrid low alpha and harmonic cavity method

    Science.gov (United States)

    Gao, Weiwei; Wang, Lin; Li, Heting

    2017-03-01

    In this paper we design a simultaneous three bunch length operating mode at the HLS-II (Hefei Light Source II) storage ring by installing two harmonic cavities and minimizing the momentum compaction factor. The short bunches (2.6 mm) presented in this work will meet the requirement of coherent millimeter-wave and sub-THz radiation experiments, while the long bunches (20 mm) will efficiently increase the total beam current. Therefore, this multiple-bunch-length operating mode allows present synchrotron users and coherent millimeter-wave users (or sub THz users) to carry out their experiments simultaneously. Since the relatively low energy characteristic of HLS-II we achieve the multiple-bunch-length operating mode without multicell superconducting RF cavities, which is technically feasible.

  16. Effects of gamma-ray irradiation on interspecific hybridization between Chamaecyparis obtusa S. et Z. and Chamaecyparis pisifera S. et Z

    Energy Technology Data Exchange (ETDEWEB)

    Maeta, Takehiko (Institute of Radiation Breeding, Omiya, Ibaraki (Japan))

    1982-03-01

    C. obtusa S. et Z. is one of the most important forest trees in Japan, and possesses high wood quality. It adapts to dry or semi-dry planting sites, but when it is planted in humid and productive soil, physiological damage is often seen, and its woods are not resistant against termite harm. On the contrary, C. pisifera S. et Z. has high adaptability to humid and productive soil, and is resistant against termite harm. In order to improve the resistance of C. obtusa against diseases and insects, an attempt to obtain a hybrid between C. obtusa and C. pisifera has been made. However, it was found to be very difficult to obtain the hybrid because of low cross compatibility. Therefore, the radiosensitivity of reproductive organs and the induction of mutation in C. obtusa and C. pisifera, the cause of interspecific incompatibility between both species, and the possibility of breaking down the incompatibility were investigated. Also, the cytological screening of the hybrids between C. obtusa and C. pisifera was made. It was considered that the acute gamma-ray irradiation from 500 to 600 R on male flowers was optimum for the hybridization of the present purpose. All of the hybrids produced in this study were triploid.

  17. Degree of circular polarization of soft X-rays emitted from a multi-polarization-mode undulator characterized by means of magnetic circular dichroism measurements.

    Science.gov (United States)

    Oura, Masaki; Nakamura, Tetsuya; Takeuchi, Tomoyuki; Senba, Yasunori; Ohashi, Haruhiko; Shirasawa, Katsutoshi; Tanaka, Takashi; Takeuchi, Masao; Furukawa, Yukito; Hirono, Toko; Ohata, Toru; Kitamura, Hideo; Shin, Shik

    2007-11-01

    The degree of circular polarization of soft X-rays emitted from the multi-polarization-mode undulator of BL17SU at SPring-8 has been deduced by means of magnetic circular dichroism in core-level X-ray absorption spectroscopy for a ferrimagnetic Gd-Fe-Co amorphous thin film. The results of reference measurements performed using well characterized undulator radiation of BL25SU at SPring-8 have also been utilized. The degrees of circular polarization were presumed for all the available operational modes and were compared with simple theoretical calculations. It was found that the calculated degrees of circular polarization were validated by the measurements reasonably well and will be useful in further experiments at BL17SU.

  18. Generation regimes of bidirectional hybridly mode-locked ultrashort pulse erbium-doped all-fiber ring laser with a distributed polarizer.

    Science.gov (United States)

    Krylov, Alexander A; Chernykh, Dmitriy S; Arutyunyan, Natalia R; Grebenyukov, Vyacheslav V; Pozharov, Anatoly S; Obraztsova, Elena D

    2016-05-20

    We report on the stable picosecond and femtosecond pulse generation from the bidirectional erbium-doped all-fiber ring laser hybridly mode-locked with a coaction of a single-walled carbon nanotube-based saturable absorber and nonlinear polarization evolution that was introduced through the insertion of the short-segment polarizing fiber. Depending on the total intracavity dispersion value, the laser emits conservative solitons, transform-limited Gaussian pulses, or highly chirped stretched pulses with almost 20 nm wide parabolic spectrum in both clockwise (CW) and counterclockwise (CCW) directions of the ring. Owing to the polarizing action in the cavity, we have demonstrated for the first time, to the best of our knowledge, an efficient tuning of soliton pulse characteristics for both CW and CCW channels via an appropriate polarization control. We believe that the bidirectional laser presented may be highly promising for gyroscopic and other dual-channel applications.

  19. 混合隔振系统自适应模糊滑模控制%Adaptive Fuzzy Sliding-mode Controller for Hybrid Vibration Isolation Systems

    Institute of Scientific and Technical Information of China (English)

    杨理华; 朱石坚; 楼京俊; 李棒

    2014-01-01

    针对机械设备被动隔振在低频段隔振效果较差的问题,建立磁致伸缩作动器的电—磁—机转化数学模型,提出一种基于自适应模糊滑模控制算法,并用李雅普诺夫方法证明控制器的稳定性,将该控制策略与磁致伸缩作动器应用于混合隔振系统中。仿真结果表明:在单频、多频及随即激励条件下,自适应模糊滑模控制器具有良好的动态特性和鲁棒性,能够提高系统隔振效率并拓宽隔振频段,有效减小传至基础的力。%Aiming at the problem of poor vibration isolation effect of passive vibration isolators of mechanical equip-ment in low frequency range, an electric-magnetic-mechanical conversion model for magnetostrictive actuators is estab-lished, and an adaptive fuzzy sliding-mode control algorithm is proposed. The stability of the controller is proved by Lyapu-nov method. Then, the control strategy and the magnetostrictive actuator are used in a hybrid vibration isolation system. The simulation results show that in whatever conditions of single frequency excitation, multi-frequency excitation or random ex-citation, the adaptive fuzzy sliding-mode controller has good dynamic characteristics and robustness. This property can also be used to improve the isolation efficiency and broaden the vibration isolation frequency band of the hybrid system, and ef-fectively reduce the force transmitted to the foundation of the mechanical equipment.

  20. In Vitro Evaluation of CBR-2092, a Novel Rifamycin-Quinolone Hybrid Antibiotic: Studies of the Mode of Action in Staphylococcus aureus▿

    Science.gov (United States)

    Robertson, Gregory T.; Bonventre, Eric J.; Doyle, Timothy B.; Du, Qun; Duncan, Leonard; Morris, Timothy W.; Roche, Eric D.; Yan, Dalai; Lynch, A. Simon

    2008-01-01

    Rifamycins have proven efficacy in the treatment of persistent bacterial infections. However, the frequency with which bacteria develop resistance to rifamycin agents restricts their clinical use to antibiotic combination regimens. In a program directed toward the synthesis of rifamycins with a lower propensity to elicit resistance development, a series of compounds were prepared that covalently combine rifamycin and quinolone pharmacophores to form stable hybrid antibacterial agents. We describe mode-of-action studies with Staphylococcus aureus of CBR-2092, a novel hybrid that combines the rifamycin SV and 4H-4-oxo-quinolizine pharmacophores. In biochemical studies, CBR-2092 exhibited rifampin-like potency as an inhibitor of RNA polymerase, was an equipotent (balanced) inhibitor of DNA gyrase and DNA topoisomerase IV, and retained activity against a prevalent quinolone-resistant variant. Macromolecular biosynthesis studies confirmed that CBR-2092 has rifampin-like effects on RNA synthesis in rifampin-susceptible strains and quinolone-like effects on DNA synthesis in rifampin-resistant strains. Studies of mutant strains that exhibited reduced susceptibility to CBR-2092 further substantiated RNA polymerase as the primary cellular target of CBR-2092, with DNA gyrase and DNA topoisomerase IV being secondary and tertiary targets, respectively, in strains exhibiting preexisting rifampin resistance. In contrast to quinolone comparator agents, no strains with altered susceptibility to CBR-2092 were found to exhibit changes consistent with altered efflux properties. The combined data indicate that CBR-2092 may have potential utility in monotherapy for the treatment of persistent S. aureus infections. PMID:18443108

  1. In vitro evaluation of CBR-2092, a novel rifamycin-quinolone hybrid antibiotic: studies of the mode of action in Staphylococcus aureus.

    Science.gov (United States)

    Robertson, Gregory T; Bonventre, Eric J; Doyle, Timothy B; Du, Qun; Duncan, Leonard; Morris, Timothy W; Roche, Eric D; Yan, Dalai; Lynch, A Simon

    2008-07-01

    Rifamycins have proven efficacy in the treatment of persistent bacterial infections. However, the frequency with which bacteria develop resistance to rifamycin agents restricts their clinical use to antibiotic combination regimens. In a program directed toward the synthesis of rifamycins with a lower propensity to elicit resistance development, a series of compounds were prepared that covalently combine rifamycin and quinolone pharmacophores to form stable hybrid antibacterial agents. We describe mode-of-action studies with Staphylococcus aureus of CBR-2092, a novel hybrid that combines the rifamycin SV and 4H-4-oxo-quinolizine pharmacophores. In biochemical studies, CBR-2092 exhibited rifampin-like potency as an inhibitor of RNA polymerase, was an equipotent (balanced) inhibitor of DNA gyrase and DNA topoisomerase IV, and retained activity against a prevalent quinolone-resistant variant. Macromolecular biosynthesis studies confirmed that CBR-2092 has rifampin-like effects on RNA synthesis in rifampin-susceptible strains and quinolone-like effects on DNA synthesis in rifampin-resistant strains. Studies of mutant strains that exhibited reduced susceptibility to CBR-2092 further substantiated RNA polymerase as the primary cellular target of CBR-2092, with DNA gyrase and DNA topoisomerase IV being secondary and tertiary targets, respectively, in strains exhibiting preexisting rifampin resistance. In contrast to quinolone comparator agents, no strains with altered susceptibility to CBR-2092 were found to exhibit changes consistent with altered efflux properties. The combined data indicate that CBR-2092 may have potential utility in monotherapy for the treatment of persistent S. aureus infections.

  2. Identification of strain fields in pure Al and hybrid Ni/Al metal foams using X-ray micro-tomography under loading

    Science.gov (United States)

    Fíla, T.; Jiroušek, O.; Jung, A.; Kumpová, I.

    2016-11-01

    Hybrid foams are materials formed by a core from a standard open cell metal foam that is during the process of electrodeposition coated by a thin layer of different nanocrystalline metals. The material properties of the base metal foam are in this way modified resulting in higher plateau stress and, more importantly, by introduction of strain-rate dependence to its deformation response. In this paper, we used time-lapse X-ray micro-tomography for the mechanical characterization of Ni/Al hybrid foams (aluminium open cell foams with nickel coating layer). To fully understand the effects of the coating layer on the material's effective properties, we compared the compressive response of the base uncoated foam to the response of the material with coating thickness of 50 and 75 μm. Digital volume correlation (DVC) was applied to obtain volumetric strain fields of the deforming micro-structure up to the densification region of the deforming cellular structure. The analysis was performed as a compressive mechanical test with simultaneous observation using X-ray radiography and tomography. A custom design experimental device was used for compression of the foam specimens in several deformation states directly in the X-ray setup. Planar X-ray images were taken during the loading phases and a X-ray tomography was performed at the end of each loading phase (up to engineering strain 22%). The samples were irradiated using micro-focus reflection type X-ray tube and images were taken using a large area flat panel detector. Tomography reconstructions were used for an identification of a strain distribution in the foam using digital volumetric correlation. A comparison of the deformation response of the coated and the uncoated foam in uniaxial quasi-static compression is summarized in the paper.

  3. A hybrid electromagnetism-like algorithm for a multi-mode resource-constrained project scheduling problem

    Directory of Open Access Journals (Sweden)

    Mohammad Hossein Sadeghi

    2013-08-01

    Full Text Available In this paper, two different sub-problems are considered to solve a resource constrained project scheduling problem (RCPSP, namely i assignment of modes to tasks and ii scheduling of these tasks in order to minimize the makespan of the project. The modified electromagnetism-like algorithm deals with the first problem to create an assignment of modes to activities. This list is used to generate a project schedule. When a new assignment is made, it is necessary to fix all mode dependent requirements of the project activities and to generate a random schedule with the serial SGS method. A local search will optimize the sequence of the activities. Also in this paper, a new penalty function has been proposed for solutions which are infeasible with respect to non-renewable resources. Performance of the proposed algorithm has been compared with the best algorithms published so far on the basis of CPU time and number of generated schedules stopping criteria. Reported results indicate excellent performance of the algorithm.

  4. Probing of Ehrlich ascites carcinoma cell using in situ aggregates of Au-NPs as SERS label created by plasmon exciting hybrid- TEM*11 laser mode

    Science.gov (United States)

    Kumar, R.; Mehta, D. S.; Saraswati, S.; Shakher, C.

    2012-02-01

    Apart from commonly employed target-specific labeling/adsorption of antibodies over Au-NPs surface for the creation of localized aggregates, an alternative approach using optical tweezers (OT) driven by hybrid-TEM*11 mode has been devised and exploited for in vitro detection of Ehrlich ascites carcinoma cells (EAC) relying on enhanced scattering. Intra-cavity generated spatially featured asymmetric (SFA) laser beam (λ = 532 nm) has effected simultaneous trapping of mice-EAC cells and in-situ crowd/assembly of incubated Au-NPs/small gold nano-aggregates (created from two or more individual Au-NPs). Relatively larger focus spot created by tightly focused SFA beam than frequently employed Gaussian-mode in OT has offered an extended working area and hence dilute heating has taken care of EAC cells. GNA improves significantly the sensitivity of diagnostics relying on scattered light and the safety and efficacy of therapeutic nanotechnologies for the diseases of cancer and vascular system in medicine.

  5. Hybrid-Mode-Assisted Long-Distance Excitation of Short-Range Surface Plasmons in a Nanotip-Enhanced Step-Index Fiber.

    Science.gov (United States)

    Tuniz, Alessandro; Chemnitz, Mario; Dellith, Jan; Weidlich, Stefan; Schmidt, Markus A

    2017-02-08

    We propose and experimentally demonstrate a monolithic nanowire-enhanced fiber-based nanoprobe for the broadband delivery of light (550-730 nm) to a deep subwavelength scale using short-range surface plasmons. The geometry is formed by a step index fiber with an integrated gold nanowire in its core and a protruding gold nanotip with sub-10 nm apex radius. We present a novel coupling scheme to excite short-range surface plasmons, whereby the radially polarized hybrid mode propagating inside the nanowire section excites the plasmonic mode close to the fiber endface, which is in turn superfocused down to nanoscale dimensions at the tip apex. We show that in this all-integrated fiber-plasmonic coupling scheme the wire length can be orders of magnitude longer than the attenuation length of short-range plasmon polaritons, yielding a broadband plasmon excitation and reducing demands in fabrication. We observe that the scattered light in the far-field from the nanotip is axially polarized and preferentially excited by a radially polarized input, unambiguously revealing that it originates from a short-range plasmon propagating on the nanotip, in agreement with simulations. This novel excitation scheme will have important applications in near-field microscopy and nanophotonics and potentially offers significantly improved resolution compared to current delivery near-field probes.

  6. A new mixed mode solid phase extraction strategy for opioids, cocaines, amphetamines and adulterants in human blood with hybrid liquid chromatography tandem mass spectrometry detection.

    Science.gov (United States)

    Dowling, Geraldine; Regan, Liam

    2011-04-05

    A rapid method has been developed to analyse morphine, codeine, 6-monoacetylmorphine, cocaine, benzoylecgonine, dihydrocodeine, cocaethylene, 3,4-methylenedioxyamphetamine, ketamine, 3,4-methylenedioxymethamphetamine, pseudoephedrine, lignocaine, benzylpiperazine, methamphetamine, amphetamine, methadone, phenethylamine and levamisole in human blood. Blood samples were cleaned up using mixed mode solid phase extraction using Evolute™ CX solid phase extraction cartridges and the sample aliquots were analysed by hybrid triple quadrupole linear ion trap (QTRAP) mass spectrometry with a runtime of 12.5 min. Multiple reaction monitoring (MRM) as survey scan and an enhanced product ion (EPI) scan as dependent scan were performed in an information-dependent acquisition (IDA) experiment. Finally, drug identification and confirmation was carried out by library search with a developed in-house MS/MS library based on EPI spectra at a collision energy spread of 35 ± 15 in positive mode and MRM ratios. The method was validated in blood, according to the criteria defined in Commission Decision 2002/657/EC. At least two MRM transitions for each substance were monitored in addition to EPI spectra. Deuterated analogues of analytes were used as internal standards for quantitation where possible. The method proved to be simple and time efficient and was implemented as an analytical strategy for the illicit drug monitoring of opioids, cocaines, amphetamines and adulterants in forensic cases of crime offenders, abusers or victims in the Republic of Ireland.

  7. Multiobjective Synergistic Scheduling Optimization Model for Wind Power and Plug-In Hybrid Electric Vehicles under Different Grid-Connected Modes

    Directory of Open Access Journals (Sweden)

    Liwei Ju

    2014-01-01

    Full Text Available In order to promote grid’s wind power absorptive capacity and to overcome the adverse impacts of wind power on the stable operation of power system, this paper establishes benefit contrastive analysis models of wind power and plug-in hybrid electric vehicles (PHEVs under the optimization goal of minimum coal consumption and pollutant emission considering multigrid connected modes. Then, a two-step adaptive solving algorithm is put forward to get the optimal system operation scheme with the highest membership degree based on the improved ε constraints method and fuzzy decision theory. Thirdly, the IEEE36 nodes 10-unit system is used as the simulation system. Finally, the sensitive analysis for PHEV’s grid connected number is made. The result shows the proposed algorithm is feasible and effective to solve the model. PHEV’s grid connection could achieve load shifting effect and promote wind power grid connection. Especially, the optimization goals reach the optimum in fully optimal charging mode. As PHEV’s number increases, both abandoned wind and thermal power generation cost would decrease and the peak and valley difference of load curve would gradually be reduced.

  8. Robust tracking control of a unicycle-type wheeled mobile manipulator using a hybrid sliding mode fuzzy neural network

    Science.gov (United States)

    Cheng, Meng-Bi; Su, Wu-Chung; Tsai, Ching-Chih

    2012-03-01

    This article presents a robust tracking controller for an uncertain mobile manipulator system. A rigid robotic arm is mounted on a wheeled mobile platform whose motion is subject to nonholonomic constraints. The sliding mode control (SMC) method is associated with the fuzzy neural network (FNN) to constitute a robust control scheme to cope with three types of system uncertainties; namely, external disturbances, modelling errors, and strong couplings in between the mobile platform and the onboard arm subsystems. All parameter adjustment rules for the proposed controller are derived from the Lyapunov theory such that the tracking error dynamics and the FNN weighting updates are ensured to be stable with uniform ultimate boundedness (UUB).

  9. Analysis Of Innovative Applications of Single DC Motor in Series and Separately Excited Mode for Hybrid Electric Solar Car

    Directory of Open Access Journals (Sweden)

    Rahat Ullah Khan,

    2010-03-01

    Full Text Available In this paper an innovative technique is proposed to run a DC series motor and converting it into D C separately excited as and when required to do regenerative braking and controlling a loaded car. In this scheme we are proposing on alternate energy source for driving the car i.e. solar PV Cell based battery charging system. The implication, basic concept and limitations of this concept are discussed. Also the mode of operations including analysis and operating conditions is also discussed. The simulation results are provided to validate the concept.

  10. Application of the linear/exponential hybrid force field scaling scheme to the bond length alternation modes of polyacetylene

    Science.gov (United States)

    Yang, Shujiang; Kertesz, Miklos

    2006-12-01

    The two bond length alternation related backbone carbon-carbon stretching Raman active normal modes of polyacetylene are notoriously difficulty to predict theoretically. We apply our new linear/exponential scaled quantum mechanical force field scheme to tackle this problem by exponentially adjusting the decay of the coupling force constants between backbone stretchings based on their distance which extends over many neighbors. With transferable scaling parameters optimized by least squares fitting to the experimental vibrational frequencies of short oligoenes, the scaled frequencies of trans-polyacetylene and its isotopic analogs agree very well with experiments. The linear/exponential scaling scheme is also applicable to the cis-polyacetylene case.

  11. 基于Spark的大数据混合计算模型%Big Data Hybrid Computing Mode Based on Spark

    Institute of Scientific and Technical Information of China (English)

    胡俊; 胡贤德; 程家兴

    2015-01-01

    The use of big data in the real world was complicated. It may contain different characteristic of data and computing. In this case, the single computing mode was mostly difficult to met the application requirements. Therefore we need to consider different computing mode of mix use. The ultimate evolution of hybrid computing mode is spark system which invented by UCBerkeley AMPLab. It covers almost all the typical big data computing mode, including iterative computing, batch computing, memory computing, flow computing (Spark Streaming), data query analysis (Shark), and map computing (GraphX). Spark provides a powerful memory computing engine and implents computing with excellent performance, while maintaining compatibility with the Hadoop platform. Therefore, with the continuous stable and mature, Spark is expected to be colocalized with Hadoop and became a new generation of big data processing systems and platforms. The paper has studied and analyed the Spark ecosystem, and set up the hybrid computing model architecture based on Spark platform, which also has illustrated the spark ecosystem can meet the application of hybrid computing model.%现实世界大数据应用复杂多样,可能会同时包含不同特征的数据和计算,在这种情况下单一的计算模式多半难以满足整个应用的需求,因此需要考虑不同计算模式的混搭使用。混合计算模式之集大成者当属UCBerkeley AMPLab的Spark系统,其涵盖了几乎所有典型的大数据计算模式,包括迭代计算、批处理计算、内存计算、流式计算(Spark Streaming)、数据查询分析计算(Shark)、以及图计算(GraphX)。 Spark提供了一个强大的内存计算引擎,实现了优异的计算性能,同时还保持与Hadoop平台的兼容性。因此,随着系统的不断稳定和成熟, Spark有望成为与Hadoop共存的新一代大数据处理系统和平台。本文详细研究和分析了Spark生态系统,建立了基于Spark平台

  12. Wind, jet, hybrid corona and hard X-ray flares: multiwavelength evolution of GRO J1655-40 during the 2005 outburst rise

    CERN Document Server

    Kalemci, E; Maccarone, T J; Dincer, T; Russell, T D; Bailyn, C; Tomsick, J A

    2016-01-01

    We have investigated the complex multiwavelength evolution of GRO J1655-40 during the rise of its 2005 outburst. We detected two hard X-ray flares, the first one during the transition from the soft state to the ultra-soft state, and the second one in the ultra-soft state. The first X-ray flare coincided with an optically thin radio flare. We also observed a hint of increased radio emission during the second X-ray flare. To explain the hard flares without invoking a secondary emission component, we fit the entire data set with the eqpair model. This single, hybrid Comptonization model sufficiently fits the data even during the hard X-ray flares if we allow reflection fractions greater than unity. In this case, the hard X-ray flares correspond to a Comptonizing corona dominated by non-thermal electrons. The fits also require absorption features in the soft and ultra-soft state which are likely due to a wind. In this work we show that the wind and the optically thin radio flare co-exist. Finally, we have also in...

  13. Wind, jet, hybrid corona and hard X-ray flares: multiwavelength evolution of GRO J1655-40 during the 2005 outburst rise

    Science.gov (United States)

    Kalemci, E.; Begelman, M. C.; Maccarone, T. J.; Dinçer, T.; Russell, T. D.; Bailyn, C.; Tomsick, J. A.

    2016-11-01

    We have investigated the complex multiwavelength evolution of GRO J1655-40 during the rise of its 2005 outburst. We detected two hard X-ray flares, the first one during the transition from the soft state to the ultra-soft state, and the second one in the ultra-soft state. The first X-ray flare coincided with an optically thin radio flare. We also observed a hint of increased radio emission during the second X-ray flare. To explain the hard flares without invoking a secondary emission component, we fit the entire data set with the eqpair model. This single, hybrid Comptonization model sufficiently fits the data even during the hard X-ray flares if we allow reflection fractions greater than unity. In this case, the hard X-ray flares correspond to a Comptonizing corona dominated by non-thermal electrons. The fits also require absorption features in the soft and ultra-soft state which are likely due to a wind. In this work we show that the wind and the optically thin radio flare co-exist. Finally, we have also investigated the radio to optical spectral energy distribution, tracking the radio spectral evolution through the quenching of the compact jet and rise of the optically thin flare, and interpreted all data using state transition models.

  14. A hybrid discrete choice model to assess the effect of awareness and attitude towards environmentally friendly travel modes

    DEFF Research Database (Denmark)

    Sottile, Eleonora; Meloni, Italo; Cherchi, Elisabetta

    2015-01-01

    (level-of-service characteristics being equal). It has been observed, though not scientifically demonstrated, that these measures can produce changes, being the result of mindful decisions. However, in some cases, as demonstrated by numerous environmental psychology studies such measures...... are not sufficient to overcome the effect of cognitive dissonance, one of the main factors hindering change. In fact it is not unusual to find discrepancies between attitudes and behaviour in travel behaviour research. The objective of the present work is to understand the relationship between awareness, attitude...... and behaviour in the context of mode choice and to measure the effect of awareness after the implementation of a soft measure after controlling for individual environmental attitudes. Using a dataset gathered in two weeks, before and after individuals are informed of the benefits of using park and ride (P...

  15. Hybrid Powder - Single Crystal X-Ray Diffraction Instrument for Planetary Mineralogical Analysis of Unprepared Samples Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose to develop a planetary exploration XRD/XRF instrument based on a hybrid diffraction approach that complements powder XRD analysis, similar to that of the...

  16. Fast scintillation timing detector using proportional-mode avalanche photodiode for nuclear resonant scattering experiments in high-energy synchrotron X-ray region

    Science.gov (United States)

    Inoue, Keisuke; Kishimoto, Shunji

    2016-01-01

    To obtain both a high count rate of >107 s-1 and a detection efficiency sufficient for high-energy X-rays of >30 keV, we propose a scintillation timing detector using a proportional-mode silicon avalanche photodiode (Si-APD) for synchrotron radiation nuclear resonant scattering. We here present results obtained with a prototype detector using a lead-loaded plastic scintillator (EJ-256) mounted on a proportional-mode Si-APD (active area size: 3 mm in diameter). The detector was operated at ‒35 °C for a better signal-to-noise ratio. Using synchrotron X-rays of 67.41 keV, which is the same energy as the first excited level of 61Ni, we successfully measured pulse-height and time spectra of the scintillation light. A good time resolution of 0.50±0.06 ns (full width at half-maximum) was obtained for 67.41 keV X-rays with a scintillator 3 mm in diameter and 2 mm thick.

  17. Identification of m =2 competent mode of complex magneto-hydro-dynamics activities during internal soft disruption based on singular value decomposition and tomography of soft-X-ray emission on the HT-7 tokamak

    Institute of Scientific and Technical Information of China (English)

    Xu Li-Qing; Mao Song-Tao; Duan Yan-Min; Hu Li-Qun; Li Er-Zhong; Chen Kai-Yun; Liu Zhi-Yuan; Chen Ye-Bin; Zhang Ji-Zong; Zhou Rui-Jie; Yang Mao

    2012-01-01

    In this paper,the singular value decomposition(SVD)method as a filter is applied before the tomographic inversion of soft-X-ray emission.Series of ‘filtered' signals including specific chronos and topos are obtained.(Here,chronos and topos are the decomposed spatial vectors and the decomposed temporal vectors,respectively).Given specific magnetic flux function with coupling m=1 and m=2 modes,the line-integrated soft-X-ray signals at all chords have been obtained.Then m=1 and m=2 modes have been identified by tomography of simulated ‘filtered' signals extracted by the SVD method.Finaly,using the experimental line-integrated soft-X-ray signals,m=2 competent mode of complex magnetohydrodynamics(MHD)activities during internal soft disruption is observed.This result demonstrates that m=2 mode plays an important role in internal disruption(Here,m is the poloidal mode number).

  18. Identification of m = 2 competent mode of complex magneto-hydro-dynamics activities during internal soft disruption based on singular value decomposition and tomography of soft-X-ray emission on the HT-7 tokamak

    Science.gov (United States)

    Xu, Li-Qing; Hu, Li-Qun; Li, Er-Zhong; Chen, Kai-Yun; Liu, Zhi-Yuan; Chen, Ye-Bin; Zhang, Ji-Zong; Zhou, Rui-Jie; Yang, Mao; Mao, Song-Tao; Duan, Yan-Min

    2012-05-01

    In this paper, the singular value decomposition (SVD) method as a filter is applied before the tomographic inversion of soft-X-ray emission. Series of ‘filtered’ signals including specific chronos and topos are obtained. (Here, chronos and topos are the decomposed spatial vectors and the decomposed temporal vectors, respectively). Given specific magnetic flux function with coupling m = 1 and m = 2 modes, the line-integrated soft-X-ray signals at all chords have been obtained. Then m = 1 and m = 2 modes have been identified by tomography of simulated ‘filtered’ signals extracted by the SVD method. Finaly, using the experimental line-integrated soft-X-ray signals, m = 2 competent mode of complex magnetohydrodynamics(MHD) activities during internal soft disruption is observed. This result demonstrates that m = 2 mode plays an important role in internal disruption (Here, m is the poloidal mode number).

  19. Measurement of the Cosmic Ray Energy Spectrum and Composition from 10^{17} to 10^{18.3} eV Using a Hybrid Fluorescence Technique

    CERN Document Server

    Abu-Zayyad, T; Bird, D J; Boyer, J; Cao, Z; Catanese, M; Chen, G F; Clay, R W; Covault, C E; Dai, H Y; Dawson, B R; Elbert, J W; Fick, B E; Fortson, Lucy F; Fowler, J W; Gibbs, K G; Glasmacher, M A K; Green, K D; Huang, A; Jui, C; Kidd, M J; Kieda, D B; Knapp, B C; Larsen, C G; Lee, W; Loh, E C; Mannel, E J; Matthews, J; Matthews, J N; Newport, B J; Nitz, D F; Ong, R A; Simpson, K M; Smith, J D; Sinclair, D; Sokolsky, P; Sommers, P; Song, C; Tang, J K K; Thomas, S B; Der Velde, J; Wiencke, L R; Wilkinson, C R; Yoshida, S; Zhang, X Z

    2001-01-01

    We study the spectrum and average mass composition of cosmic rays with primary energies between 10^{17} eV and 10^{18} eV using a hybrid detector consisting of the High Resolution Fly's Eye (HiRes) prototype and the MIA muon array. Measurements have been made of the change in the depth of shower maximum as a function of energy. A complete Monte Carlo simulation of the detector response and comparisons with shower simulations leads to the conclusion that the cosmic ray intensity is changing f rom a heavier to a lighter composition in this energy range. The spectrum is consistent with earlier Fly's Eye measurements and supports the previously found steepening near 4 \\times 10^{17} eV .

  20. Characterization of a hybrid target multi-keV x-ray source by a multi-parameter statistical analysis of titanium K-shell emission

    Science.gov (United States)

    Primout, M.; Babonneau, D.; Jacquet, L.; Gilleron, F.; Peyrusse, O.; Fournier, K. B.; Marrs, R.; May, M. J.; Heeter, R. F.; Wallace, R. J.

    2016-03-01

    We have studied the titanium K-shell emission spectra from multi-keV x-ray source experiments with hybrid targets on the OMEGA laser facility. Using the collisional-radiative TRANSPEC code, dedicated to K-shell spectroscopy, we reproduced the main features of the detailed spectra measured with the time-resolved MSPEC spectrometer. We have developed a general method to infer the Ne, Te and Ti characteristics of the target plasma from the spectral analysis (ratio of integrated Lyman-α to Helium-α in-band emission and the peak amplitude of individual line ratios) of the multi-keV x-ray emission. These thermodynamic conditions are compared to those calculated independently by the radiation-hydrodynamics transport code FCI2.

  1. Evaluation of 320x240 pixel LEC GaAs Schottky barrier X-ray imaging arrays, hybridized to CMOS readout circuit based on charge integration

    CERN Document Server

    Irsigler, R; Alverbro, J; Borglind, J; Froejdh, C; Helander, P; Manolopoulos, S; O'Shea, V; Smith, K

    1999-01-01

    320x240 pixels GaAs Schottky barrier detector arrays were fabricated, hybridized to silicon readout circuits, and subsequently evaluated. The detector chip was based on semi-insulating LEC GaAs material. The square shaped pixel detector elements were of the Schottky barrier type and had a pitch of 38 mu m. The GaAs wafers were thinned down prior to the fabrication of the ohmic back contact. After dicing, the chips were indium bump, flip-chip bonded to CMOS readout circuits based on charge integration, and finally evaluated. A bias voltage between 50 and 100 V was sufficient to operate the detector. Results on I-V characteristics, noise behaviour and response to X-ray radiation are presented. Images of various objects and slit patterns were acquired by using a standard dental imaging X-ray source. The work done was a part of the XIMAGE project financed by the European Community (Brite-Euram). (author)

  2. Contrasting Behaviour from Two Be/X-ray Binary Pulsars: Insights into Differing Neutron Star Accretion Modes

    Science.gov (United States)

    Townsend, L. J.; Drave, S. P.; Hill, A. B.; Coe, M. J.; Corbet, R. H. D.; Bird, A. J.

    2013-01-01

    In this paper we present the identification of two periodic X-ray signals coming from the direction of the Small Magellanic Cloud (SMC). On detection with the Rossi X-ray Timing Explorer (RXTE), the 175.4 s and 85.4 s pulsations were considered to originate from new Be/X-ray binary (BeXRB) pulsars with unknown locations. Using rapid follow-up INTEGRAL and XMM-Newton observations, we show the first pulsar (designated SXP175) to be coincident with a candidate high-mass X-ray binary (HMXB) in the northern bar region of the SMC undergoing a small Type II outburst. The orbital period (87d) and spectral class (B0-B0.5IIIe) of this system are determined and presented here for the first time. The second pulsar is shown not to be new at all, but is consistent with being SXP91.1 - a pulsar discovered at the very beginning of the 13 year long RXTE key monitoring programme of the SMC. Whilst it is theoretically possible for accreting neutron stars to change spin period so dramatically over such a short time, the X-ray and optical data available for this source suggest this spin-up is continuous during long phases of X-ray quiescence, where accretion driven spin-up of the neutron star should be minimal.

  3. Material/element-dependent fluorescence-yield modes on soft X-ray absorption spectroscopy of cathode materials for Li-ion batteries

    Directory of Open Access Journals (Sweden)

    Daisuke Asakura

    2016-03-01

    Full Text Available We evaluate the utilities of fluorescence-yield (FY modes in soft X-ray absorption spectroscopy (XAS of several cathode materials for Li-ion batteries. In the case of total-FY (TFY XAS for LiNi0.5Mn1.5O4, the line shape of the Mn L3-edge XAS was largely distorted by the self-absorption and saturation effects, while the distortions were less pronounced at the Ni L3 edge. The distortions were suppressed for the inverse-partial-FY (IPFY spectra. We found that, in the cathode materials, the IPFY XAS is highly effective for the Cr, Mn, and Fe L edges and the TFY and PFY modes are useful enough for the Ni L edge which is far from the O K edge.

  4. Influence of surface hydroxylation on 3-aminopropyltriethoxysilane growth mode during chemical functionalization of GaN Surfaces: an angle-resolved X-ray photoelectron spectroscopy Study.

    Science.gov (United States)

    Arranz, A; Palacio, C; García-Fresnadillo, D; Orellana, G; Navarro, A; Muñoz, E

    2008-08-19

    A comparative study of the chemical functionalization of undoped, n- and p-type GaN layers grown on sapphire substrates by metal-organic chemical vapor deposition was carried out. Both types of samples were chemically functionalized with 3-aminopropyltriethoxysilane (APTES) using a well-established silane-based approach for functionalizing hydroxylated surfaces. The untreated surfaces as well as those modified by hydroxylation and APTES deposition were analyzed using angle-resolved X-ray photoelectron spectroscopy. Strong differences were found between the APTES growth modes on n- and p-GaN surfaces that can be associated with the number of available hydroxyl groups on the GaN surface of each sample. Depending on the density of surface hydroxyl groups, different mechanisms of APTES attachment to the GaN surface take place in such a way that the APTES growth mode changes from a monolayer to a multilayer growth mode when the number of surface hydroxyl groups is decreased. Specifically, a monolayer growth mode with a surface coverage of approximately 78% was found on p-GaN, whereas the formation of a dense film, approximately 3 monolayers thick, was observed on n-GaN.

  5. Spoof Plasmon Hybridization

    CERN Document Server

    Zhang, Jingjing; Luo, Yu; Shen, Xiaopeng; Maier, Stefan A; Cui, Tie Jun

    2016-01-01

    Plasmon hybridization between closely spaced nanoparticles yields new hybrid modes not found in individual constituents, allowing for the engineering of resonance properties and field enhancement capabilities of metallic nanostructure. Experimental verifications of plasmon hybridization have been thus far mostly limited to optical frequencies, as metals cannot support surface plasmons at longer wavelengths. Here, we introduce the concept of 'spoof plasmon hybridization' in highly conductive metal structures and investigate experimentally the interaction of localized surface plasmon resonances (LSPR) in adjacent metal disks corrugated with subwavelength spiral patterns. We show that the hybridization results in the splitting of spoof plasmon modes into bonding and antibonding resonances analogous to molecular orbital rule and plasmonic hybridization in optical spectrum. These hybrid modes can be manipulated to produce enormous field enhancements (larger than 5000) by tuning the separation between disks or alte...

  6. Operating Modes and Cooling Capabilities of the 3-Stage ADR Developed for the Soft-X-Ray Spectrometer Instrument on Astro-H

    Science.gov (United States)

    Shirron, Peter J.; Kimball, Mark O.; James, Bryan L.; Muench, Theo; DiPirro, Michael J.; Letmate, Richard V.; Sampson, Michael A.; Bialas, Tom G.; Sneiderman, Gary A.; Porter, Frederick S.; hide

    2015-01-01

    A 3-stage adiabatic demagnetization refrigerator (ADR) is used on the Soft X-ray Spectrometer instrument on Astro-H to cool a 6x6 array of x-ray microcalorimeters to 50 mK. The ADR is supported by a cryogenic system consisting of a superfluid helium tank, a 4.5 K Joule-Thomson (JT) cryocooler, and additional 2-stage Stirling cryocoolers that pre-cool the JT cooler and cool radiation shields within the cryostat. The ADR is configured so that it can use either the liquid helium or the JT cryocooler as its heat sink, giving the instrument an unusual degree of tolerance for component failures or degradation in the cryogenic system. The flight detector assembly, ADR and dewar were integrated into the flight dewar in early 2014, and have since been extensively characterized and calibrated. This paper summarizes the operation and performance of the ADR in all of its operating modes

  7. Discriminator amplitude walk correction in gamma-ray coincidence experiments using list-mode time-stamping data acquisition

    Science.gov (United States)

    Khamzin, Murat K.; Valentine, John D.

    2003-06-01

    When pulse amplitude and time stamp are recorded in list-mode time-stamping data acquisition, it is possible to correct for the system amplitude walk, typically observed as the time pickoff dependence on pulse amplitude. In this study, a method of correcting for amplitude walk during post-acquisition analysis of such list mode data is developed and demonstrated. The method is demonstrated using a simple two-channel system and a photon source capable of producing coincidence events ( 22Na). Two leading-edge discriminators, vulnerable to the amplitude walk, were used to produce the time pickoffs. The resulting corrected data show an amplitude walk less than the detector timing resolution. The method developed can be used in list-mode data acquisition systems such as medical imaging scanners or Compton scatter cameras.

  8. Core-Shell-Corona Silica Hybrid Nanoparticles Templated by Spherical Polyelectrolyte Brushes: A Study by Small Angle X-ray Scattering.

    Science.gov (United States)

    Han, Haoya; Li, Li; Wang, Weihua; Tian, Yuchuan; Wang, Yunwei; Wang, Junyou; von Klitzing, Regine; Guo, Xuhong

    2017-09-06

    Core-shell-corona silica/polymer hybrid nanoparticles with narrow size distribution were prepared in the template of spherical polyelectrolyte brushes (SPB) which consist of a solid polystyrene (PS) core densely grafted with linear poly(acrylic acid) (PAA) chains. The microstructure of obtained hybrid nanoparticles was studied by small-angle X-ray scattering (SAXS) and in combination with dynamic light scattering (DLS) and transmission electron microscopy (TEM). The generation of silica shell within the brush is confirmed by the significant increase of the electron density in the shell, and the silica shell showed a unique inner-loose-outer-dense structure, whose thickness is pH sensitive but is insensitive to ionic strength as revealed by fitting SAXS data. After dissolving the PS core, hollow silica nanoparticles were obtained and determined by SAXS, which should be ideal carriers for pH-triggered drug delivery. SAXS is confirmed to be a powerful method to characterize the core-shell-corona silica/polymer hybrid and hollow silica nanoparticles.

  9. Contrasting behaviour from two Be/X-ray binary pulsars: insights into differing neutron star accretion modes

    CERN Document Server

    Townsend, L J; Hill, A B; Coe, M J; Corbet, R H D; Bird, A J

    2013-01-01

    In this paper we present the identification of two periodic X-ray signals coming from the direction of the Small Magellanic Cloud (SMC). On detection with the Rossi X-ray Timing Explorer (RXTE), the 175.4s and 85.4s pulsations were considered to originate from new Be/X-ray binary (BeXRB) pulsars with unknown locations. Using rapid follow-up INTEGRAL and XMM-Newton observations, we show the first pulsar (designated SXP175) to be coincident with a candidate high-mass X-ray binary (HMXB) in the northern bar region of the SMC undergoing a small Type II outburst. The orbital period (87d) and spectral class (B0-B0.5IIIe) of this system are determined and presented here for the first time. The second pulsar is shown not to be new at all, but is consistent with being SXP91.1 - a pulsar discovered at the very beginning of the 13 year long RXTE key monitoring programme of the SMC. Whilst it is theoretically possible for accreting neutron stars to change spin period so dramatically over such a short time, the X-ray and ...

  10. High-speed reconfigurable card-to-card optical interconnects based on hybrid free-space and multi-mode fiber propagations.

    Science.gov (United States)

    Wang, Ke; Nirmalathas, Ampalavanapillai; Lim, Christina; Skafidas, Efstratios; Alameh, Kamal

    2013-12-16

    In this paper, a high-speed reconfigurable card-to-card optical interconnect architecture based on hybrid free-space and multi-mode fiber (MMF) propagation is proposed. The use of free-space signal transmission provides flexibility and reconfigurability and the MMF extends the achievable interconnection range. A printed-circuit-board (PCB) based integrated optical interconnect module is designed and developed and proof-of-concept demonstration experiments are carried out. Results show that 3 × 10 Gb/s reconfigurable optical interconnect is realized with ~12 cm free-space propagation and a 10 m MMF length. In addition, since air turbulence due to high temperature of electronic components and heat dissipation fans always exists in typical interconnect environments and it normally results in system performance degradation, its impact on the proposed reconfigurable optical interconnect scheme is also experimentally investigated. Results indicate that even with comparatively strong air turbulence, 3 × 10 Gb/s optical interconnects with flexibility can still be achieved and the power penalty is <0.7 dB.

  11. Effects of radio frequency fields in the lower hybrid range on temperature gradient driven drift-modes in tokamaks: Momentum and impurity transport

    Science.gov (United States)

    Das, Salil; Jhang, Hogun; Singh, R.; Nordman, H.

    2016-10-01

    The significant effect of impurities in radiation losses and plasma dilution, which result in lower fusion power, and the evaluation of the important effects of intrinsic rotation on transport barrier formation, determination of momentum pinch velocity and its theoretical basis, in tokamak performance is studied using the four-wave parametric process using an electrostatic, collisionless fluid model for ion-temperature-gradient and trapped-electron mode driven turbulence in the presence of radio frequency fields in the lower hybrid (LH) range of frequencies. The beating of the pump and the sidebands exert a ponderomotive force on electrons, modifying the eigenfrequency of the drift waves and influencing the growth rates and the turbulent transport properties. Explicit expressions for the non-linear growth rate and the associated ion thermal conductivity and effective impurity diffusivity are derived. The effects of the rf fields on the momentum and impurity transport coefficients are evaluated for key parameters like rf power, temperature gradients, and magnetic shear. Prince Georges Community College, Largo, Maryland 20774, USA.

  12. One-pot preparation of a mixed-mode organic-silica hybrid monolithic capillary column and its application in determination of endogenous gibberellins in plant tissues.

    Science.gov (United States)

    Zhang, Zheng; Hao, Yan-Hong; Ding, Jun; Xu, Sheng-Nan; Yuan, Bi-Feng; Feng, Yu-Qi

    2015-10-16

    A newly improved one-pot method, based on "thiol-ene" click chemistry and sol-gel approach in microemulsion system, was developed for the preparation of C8/PO(OH)2-silica hybrid monolithic capillary column. The prepared monolith possesses large specific surface area, narrow mesopore size distribution and high column efficiency. The monolithic column was demonstrated to have cation exchange/reversed-phase (CX/RP) mixed-mode retention for analytes on nano-liquid chromatography (nano-LC). On the basis of the developed nano-LC system with MS detector coupled to pipette tip solid phase extraction (PT-SPE) and derivatization process, we then realized simultaneous determination of 10 gibberellins (GAs) with low limits of detection (LODs, 0.003-0.025 ng/mL). Furthermore, 6 endogenous GAs in only 5mg rice leaves (fresh weight) were successfully detected and quantified. The developed PT-SPE-nano-LC-MS strategy may offer promising applications in the determination of low abundant bioactive molecules from complex matrix.

  13. One-dimensional full wave treatment of mode conversion process at the ion-ion hybrid resonance in a bounded tokamak plasma

    Energy Technology Data Exchange (ETDEWEB)

    Monakhov, I.; Becoulet, A.; Fraboulet, D.; NGuyen, F

    1998-09-01

    A consistent picture of the mode conversion (MC) process at the ion-ion hybrid resonance in a bounded plasma of a tokamak is discussed, which clarifies the role of the global fast wave interference and cavity effects in the determination of the MC efficiency. This picture is supported by simulations with one-dimensional full wave kinetic code `VICE`. The concept of the `global resonator`, formed by the R = n{sup 2}{sub ||} boundary cutoffs [B. Saoutic et al., Phys. Rev. Lett. 76, 1647 (1996)], is justified, as well as the importance of a proper tunneling factor choice {eta}{sub cr} = 0.22 [A. K. Ram et al., Phys. Plasmas 3, 1976 (1996)]. The MC scheme behavior appears to be very sensitive to the MC layer position relative to the global wave field pattern, i.e. to the local value of `poloidal` electric field at the resonance. Optimal MC regimes are found to be attainable without requirement of a particular parallel wavenumber choice. (author) 40 refs.

  14. The Pierre Auger Observatory scaler mode for the study of solar activity modulation of galactic cosmic rays

    Energy Technology Data Exchange (ETDEWEB)

    Abreu, P.; /Lisbon, LIFEP /Lisbon, IST; Aglietta, M.; /Turin Observ. /Turin U. /INFN, Turin; Ahn, E.J.; /Fermilab; Allard, D.; /APC, Paris; Allekotte, I.; /Centro Atomico Bariloche /Balseiro Inst., San Carlos de Bariloche; Allen, J.; /New York U.; Alvarez Castillo, J.; /Mexico U.; Alvarez-Muniz, J.; /Santiago de Compostela U.; Ambrosio, M.; /Naples U. /INFN, Naples; Aminaei, A.; /Nijmegen U., IMAPP; Anchordoqui, L.; /Wisconsin U., Milwaukee /Lisbon, LIFEP /Lisbon, IST

    2011-01-01

    Since data-taking began in January 2004, the Pierre Auger Observatory has been recording the count rates of low energy secondary cosmic ray particles for the self-calibration of the ground detectors of its surface detector array. After correcting for atmospheric effects, modulations of galactic cosmic rays due to solar activity and transient events are observed. Temporal variations related with the activity of the heliosphere can be determined with high accuracy due to the high total count rates. In this study, the available data are presented together with an analysis focused on the observation of Forbush decreases, where a strong correlation with neutron monitor data is found.

  15. The Pierre Auger Observatory scaler mode for the study of solar activity modulation of galactic cosmic rays

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-01-15

    Since data-taking began in January 2004, the Pierre Auger Observatory has been recording the count rates of low energy secondary cosmic ray particles for the self-calibration of the ground detectors of its surface detector array. After correcting for atmospheric effects, modulations of galactic cosmic rays due to solar activity and transient events are observed. Temporal variations related with the activity of the heliosphere can be determined with high accuracy due to the high total count rates. In this study, the available data are presented together with an analysis focused on the observation of Forbush decreases, where a strong correlation with neutron monitor data is found.

  16. Application of optimization technique to noncrystalline x-ray diffraction microscopy: Guided hybrid input-output method

    Science.gov (United States)

    Chen, Chien-Chun; Miao, Jianwei; Wang, C. W.; Lee, T. K.

    2007-08-01

    We have developed an algorithm that combines the concept of optimization with the conventional hybrid input-output (HIO) algorithm for phase retrieval of oversampled diffraction intensities. In particular, the optimization algorithm of guiding searching direction to locate the global minimum has been implemented. Compared with HIO, this guided HIO algorithm retrieves the lost phase information from diffraction intensities with much better accuracy.

  17. The Pierre Auger Observatory scaler mode for the study of solar activity modulation of galactic cosmic rays

    NARCIS (Netherlands)

    Abreu, P.; Aglietta, M.; Ahn, E. J.; Allard, D.; Allekotte, I.; Allen, J.; Alvarez Castillo, J.; Alvarez-Muniz, J.; Ambrosio, M.; Aminaei, A.; Anchordoqui, L.; Andringa, S.; Anticic, T.; Anzalone, A.; Aramo, C.; Arganda, E.; Arisaka, K.; Arqueros, F.; Asorey, H.; Assis, P.; Aublin, J.; Ave, M.; Avenier, M.; Avila, G.; Baecker, T.; Badagnani, D.; Balzer, M.; Barber, K. B.; Barbosa, A. F.; Bardenet, R.; Barroso, S. L. C.; Baughman, B.; Beatty, J. J.; Becker, B. R.; Becker, K. H.; Belletoile, A.; Bellido, J. A.; BenZvi, S.; Berat, C.; Bergmann, T.; Bertou, X.; Biermann, P. L.; Billoir, P.; Blanco, F.; Blanco, M.; Bleve, C.; Bluemer, H.; Bohacova, M.; Boncioli, D.; Bonifazi, C.; Bonino, R.; Borodai, N.; Brack, J.; Brogueira, P.; Brown, W. C.; Bruijn, R.; Buchholz, P.; Bueno, A.; Burton, R. E.; Busca, N. G.; Caballero-Mora, K. S.; Caramete, L.; Caruso, R.; Castellina, A.; Catalano, O.; Cataldi, G.; Cazon, L.; Cester, R.; Chauvin, J.; Chiavassa, A.; Chinellato, J. A.; Chou, A.; Chudoba, J.; Clay, R. W.; Colombo, E.; Coluccia, M. R.; Conceicao, R.; Contreras, F.; Cook, H.; Cooper, M. J.; Coppens, J.; Cordier, A.; Cotti, U.; Coutu, S.; Covault, C. E.; Creusot, A.; Criss, A.; Cronin, J.; Curutiu, A.; Dagoret-Campagne, S.; Dallier, R.; Dasso, S.; Daumiller, K.; Dawson, B. R.; de Almeida, R. M.; De Domenico, M.; De Donato, C.; de Jong, S. J.; De La Vega, G.; de Mello Junior, W. J. M.; de Mello Neto, J. R. T.; De Mitri, I.; de Souza, V.; de Vries, K. D.; Decerprit, G.; del Peral, L.; Deligny, O.; Della Selva, A.; Dembinski, H.; Denkiewicz, A.; Di Giulio, C.; Diaz, J. C.; Diaz Castro, M. L.; Diep, P. N.; Dobrigkeit, C.; D'Olivo, J. C.; Dong, P. N.; Dorofeev, A.; dos Anjos, J. C.; Dova, M. T.; D'Urso, D.; Dutan, I.; Ebr, J.; Engel, R.; Erdmann, M.; Escobar, C. O.; Etchegoyen, A.; San Luis, P. Facal; Falcke, H.; Farrar, G.; Fauth, A. C.; Fazzini, N.; Ferguson, A. P.; Ferrero, A.; Fick, B.; Filevich, A.; Filipcic, A.; Fleck, I.; Fliescher, S.; Fracchiolla, C. E.; Fraenkel, E. D.; Froehlich, U.; Fuchs, B.; Fulgione, W.; Gamarra, R. F.; Gambetta, S.; Garcia, B.; Garcia Gamez, D.; Garcia-Pinto, D.; Garrido, X.; Gascon, A.; Gelmini, G.; Gemmeke, H.; Gesterling, K.; Ghia, P. L.; Giaccari, U.; Giller, M.; Glass, H.; Gold, M. S.; Golup, G.; Gomez Albarracin, F.; Gomez Berisso, M.; Goncalves, P.; Gonzalez, D.; Gonzalez, J. G.; Gookin, B.; Gora, D.; Gorgi, A.; Gouffon, P.; Gozzini, S. R.; Grashorn, E.; Grebe, S.; Grigat, M.; Grillo, A. F.; Guardincerri, Y.; Guarino, F.; Guedes, G. P.; Hague, J. D.; Hansen, P.; Harari, D.; Harmsma, S.; Harton, J. L.; Haungs, A.; Hebbeker, T.; Heck, D.; Herve, A. E.; Hojvat, C.; Holmes, V. C.; Homola, P.; Hoerandel, J. R.; Horneffer, A.; Hrabovsky, M.; Huege, T.; Insolia, A.; Ionita, F.; Italiano, A.; Jiraskova, S.; Kadija, K.; Kaducak, M.; Kampert, K. H.; Karhan, P.; Karova, T.; Kasper, P.; Kegl, B.; Keilhauer, B.; Keivani, A.; Kelley, J. L.; Kemp, E.; Kieckhafer, R. M.; Klages, H. O.; Kleifges, M.; Kleinfeller, J.; Knapp, J.; Koang, D. -H.; Kotera, K.; Krohm, N.; Kroemer, O.; Kruppke-Hansen, D.; Kuehn, F.; Kuempel, D.; Kulbartz, J. K.; Kunka, N.; La Rosa, G.; Lachaud, C.; Lautridou, P.; Leao, M. S. A. B.; Lebrun, D.; Lebrun, P.; Leigui de Oliveira, M. A.; Lemiere, A.; Letessier-Selvon, A.; Lhenry-Yvon, I.; Link, K.; Lopez, R.; Lopez Agueera, A.; Louedec, K.; Lozano Bahilo, J.; Lucero, A.; Ludwig, M.; Lyberis, H.; Maccarone, M. C.; Macolino, C.; Maldera, S.; Mandat, D.; Mantsch, P.; Mariazzi, A. G.; Marin, V.; Maris, I. C.; Marquez Falcon, H. R.; Marsella, G.; Martello, D.; Martinez Bravo, O.; Mathes, H. J.; Matthews, J.; Matthews, J. A. J.; Matthiae, G.; Maurizio, D.; Mazur, P. O.; Medina-Tanco, G.; Melissas, M.; Melo, D.; Menichetti, E.; Menshikov, A.; Meurer, C.; Micanovic, S.; Micheletti, M. I.; Miller, W.; Miramonti, L.; Mollerach, S.; Monasor, M.; Ragaigne, D. Monnier; Montanet, F.; Morales, B.; Morello, C.; Moreno, E.; Moreno, J. C.; Morris, C.; Mostafa, M.; Mueller, S.; Muller, M. A.; Mueller, G.; Muenchmeyer, M.; Mussa, R.; Navarra, G.; Navarro, J. L.; Navas, S.; Necesal, P.; Nellen, L.; Nhung, P. T.; Nierstenhoefer, N.; Nitz, D.; Nosek, D.; Nozka, L.; Nyklicek, M.; Oehlschlaeger, J.; Olinto, A.; Oliva, P.; Olmos-Gilbaja, V. M.; Ortiz, M.; Pacheco, N.; Pakk Selmi-Dei, D.; Palatka, M.; Pallotta, J.; Palmieri, N.; Parente, G.; Parizot, E.; Parra, A.; Parrisius, J.; Parsons, R. D.; Pastor, S.; Paul, T.; Pavlidou, V.; Payet, K.; Pech, M.; Pekala, J.; Pelayo, R.; Pepe, I. M.; Perrone, L.; Pesce, R.; Petermann, E.; Petrera, S.; Petrinca, P.; Petrolini, A.; Petrov, Y.; Petrovic, J.; Pfendner, C.; Phan, N.; Piegaia, R.; Pierog, T.; Pieroni, P.; Pimenta, M.; Pirronello, V.; Platino, M.; Ponce, V. H.; Pontz, M.; Privitera, P.; Prouza, M.; Quel, E. J.; Rautenberg, J.; Ravel, O.; Ravignani, D.; Revenu, B.; Ridky, J.; Riggi, S.; Risse, M.; Ristori, P.; Rivera, H.; Riviere, C.; Rizi, V.; Robledo, C.; Rodriguez, G.; Rodriguez Martino, J.; Rodriguez Rojo, J.; Rodriguez-Cabo, I.; Rodriguez-Frias, M. D.; Ros, G.; Rosado, J.; Rossler, T.; Roth, M.; Rouille-d'Orfeuil, B.; Roulet, E.; Rovero, A. C.; Salamida, F.; Salazar, H.; Salina, G.; Sanchez, F.; Santander, M.; Santo, C. E.; Santos, E.; Santos, E. M.; Sarazin, F.; Sarkar, S.; Sato, R.; Scharf, N.; Scherini, V.; Schieler, H.; Schiffer, P.; Schmidt, A.; Schmidt, F.; Schmidt, T.; Scholten, O.; Schoorlemmer, H.; Schovancova, J.; Schovanek, P.; Schroeder, F.; Schulte, S.; Schuessler, F.; Schuster, D.; Sciutto, S. J.; Scuderi, M.; Segreto, A.; Semikoz, D.; Settimo, M.; Shadkam, A.; Shellard, R. C.; Sidelnik, I.; Sigl, G.; Smialkowski, A.; Smida, R.; Snow, G. R.; Sommers, P.; Sorokin, J.; Spinka, H.; Squartini, R.; Stapleton, J.; Stasielak, J.; Stephan, M.; Strazzeri, E.; Stutz, A.; Suarez, F.; Suomijaervi, T.; Supanitsky, A. D.; Susa, T.; Sutherland, M. S.; Swain, J.; Szadkowski, Z.; Tamashiro, A.; Tapia, A.; Tarutina, T.; Tascau, O.; Tcaciuc, R.; Tcherniakhovski, D.; Tegolo, D.; Thao, N. T.; Thomas, D.; Tiffenberg, J.; Timmermans, C.; Tiwari, D. K.; Tkaczyk, W.; Todero Peixoto, C. J.; Tome, B.; Tonachini, A.; Travnicek, P.; Tridapalli, D. B.; Tristram, G.; Trovato, E.; Tueros, M.; Ulrich, R.; Unger, M.; Urban, M.; Valdes Galicia, J. F.; Valino, I.; Valore, L.; van den Berg, A. M.; Vargas Cardenas, B.; Vazquez, J. R.; Vazquez, R. A.; Veberic, D.; Venters, T.; Verzi, V.; Videla, M.; Villasenor, L.; Wahlberg, H.; Wahrlich, P.; Wainberg, O.; Warner, D.; Watson, A. A.; Weber, M.; Weidenhaupt, K.; Weindl, A.; Westerhoff, S.; Whelan, B. J.; Wieczorek, G.; Wiencke, L.; Wilczynska, B.; Wilczynski, H.; Will, M.; Williams, C.; Winchen, T.; Winders, L.; Winnick, M. G.; Wommer, M.; Wundheiler, B.; Yamamoto, T.; Younk, P.; Yuan, G.; Yushkov, A.; Zamorano, B.; Zas, E.; Zavrtanik, D.; Zavrtanik, M.; Zaw, I.; Zepeda, A.; Ziolkowski, M.; Martin, L.

    2011-01-01

    Since data-taking began in January 2004, the Pierre Auger Observatory has been recording the count rates of low energy secondary cosmic ray particles for the self-calibration of the ground detectors of its surface detector array. After correcting for atmospheric effects, modulations of galactic cosm

  18. The Pierre Auger Observatory scaler mode for the study of solar activity modulation of galactic cosmic rays

    NARCIS (Netherlands)

    Abreu, P.; Aglietta, M.; Ahn, E. J.; Allard, D.; Allekotte, I.; Allen, J.; Alvarez Castillo, J.; Alvarez-Muniz, J.; Ambrosio, M.; Aminaei, A.; Anchordoqui, L.; Andringa, S.; Anticic, T.; Anzalone, A.; Aramo, C.; Arganda, E.; Arisaka, K.; Arqueros, F.; Asorey, H.; Assis, P.; Aublin, J.; Ave, M.; Avenier, M.; Avila, G.; Baecker, T.; Badagnani, D.; Balzer, M.; Barber, K. B.; Barbosa, A. F.; Bardenet, R.; Barroso, S. L. C.; Baughman, B.; Beatty, J. J.; Becker, B. R.; Becker, K. H.; Belletoile, A.; Bellido, J. A.; BenZvi, S.; Berat, C.; Bergmann, T.; Bertou, X.; Biermann, P. L.; Billoir, P.; Blanco, F.; Blanco, M.; Bleve, C.; Bluemer, H.; Bohacova, M.; Boncioli, D.; Bonifazi, C.; Bonino, R.; Borodai, N.; Brack, J.; Brogueira, P.; Brown, W. C.; Bruijn, R.; Buchholz, P.; Bueno, A.; Burton, R. E.; Busca, N. G.; Caballero-Mora, K. S.; Caramete, L.; Caruso, R.; Castellina, A.; Catalano, O.; Cataldi, G.; Cazon, L.; Cester, R.; Chauvin, J.; Chiavassa, A.; Chinellato, J. A.; Chou, A.; Chudoba, J.; Clay, R. W.; Colombo, E.; Coluccia, M. R.; Conceicao, R.; Contreras, F.; Cook, H.; Cooper, M. J.; Coppens, J.; Cordier, A.; Cotti, U.; Coutu, S.; Covault, C. E.; Creusot, A.; Criss, A.; Cronin, J.; Curutiu, A.; Dagoret-Campagne, S.; Dallier, R.; Dasso, S.; Daumiller, K.; Dawson, B. R.; de Almeida, R. M.; De Domenico, M.; De Donato, C.; de Jong, S. J.; De La Vega, G.; de Mello Junior, W. J. M.; de Mello Neto, J. R. T.; De Mitri, I.; de Souza, V.; de Vries, K. D.; Decerprit, G.; del Peral, L.; Deligny, O.; Della Selva, A.; Dembinski, H.; Denkiewicz, A.; Di Giulio, C.; Diaz, J. C.; Diaz Castro, M. L.; Diep, P. N.; Dobrigkeit, C.; D'Olivo, J. C.; Dong, P. N.; Dorofeev, A.; dos Anjos, J. C.; Dova, M. T.; D'Urso, D.; Dutan, I.; Ebr, J.; Engel, R.; Erdmann, M.; Escobar, C. O.; Etchegoyen, A.; San Luis, P. Facal; Falcke, H.; Farrar, G.; Fauth, A. C.; Fazzini, N.; Ferguson, A. P.; Ferrero, A.; Fick, B.; Filevich, A.; Filipcic, A.; Fleck, I.; Fliescher, S.; Fracchiolla, C. E.; Fraenkel, E. D.; Froehlich, U.; Fuchs, B.; Fulgione, W.; Gamarra, R. F.; Gambetta, S.; Garcia, B.; Garcia Gamez, D.; Garcia-Pinto, D.; Garrido, X.; Gascon, A.; Gelmini, G.; Gemmeke, H.; Gesterling, K.; Ghia, P. L.; Giaccari, U.; Giller, M.; Glass, H.; Gold, M. S.; Golup, G.; Gomez Albarracin, F.; Gomez Berisso, M.; Goncalves, P.; Gonzalez, D.; Gonzalez, J. G.; Gookin, B.; Gora, D.; Gorgi, A.; Gouffon, P.; Gozzini, S. R.; Grashorn, E.; Grebe, S.; Grigat, M.; Grillo, A. F.; Guardincerri, Y.; Guarino, F.; Guedes, G. P.; Hague, J. D.; Hansen, P.; Harari, D.; Harmsma, S.; Harton, J. L.; Haungs, A.; Hebbeker, T.; Heck, D.; Herve, A. E.; Hojvat, C.; Holmes, V. C.; Homola, P.; Hoerandel, J. R.; Horneffer, A.; Hrabovsky, M.; Huege, T.; Insolia, A.; Ionita, F.; Italiano, A.; Jiraskova, S.; Kadija, K.; Kaducak, M.; Kampert, K. H.; Karhan, P.; Karova, T.; Kasper, P.; Kegl, B.; Keilhauer, B.; Keivani, A.; Kelley, J. L.; Kemp, E.; Kieckhafer, R. M.; Klages, H. O.; Kleifges, M.; Kleinfeller, J.; Knapp, J.; Koang, D. -H.; Kotera, K.; Krohm, N.; Kroemer, O.; Kruppke-Hansen, D.; Kuehn, F.; Kuempel, D.; Kulbartz, J. K.; Kunka, N.; La Rosa, G.; Lachaud, C.; Lautridou, P.; Leao, M. S. A. B.; Lebrun, D.; Lebrun, P.; Leigui de Oliveira, M. A.; Lemiere, A.; Letessier-Selvon, A.; Lhenry-Yvon, I.; Link, K.; Lopez, R.; Lopez Agueera, A.; Louedec, K.; Lozano Bahilo, J.; Lucero, A.; Ludwig, M.; Lyberis, H.; Maccarone, M. C.; Macolino, C.; Maldera, S.; Mandat, D.; Mantsch, P.; Mariazzi, A. G.; Marin, V.; Maris, I. C.; Marquez Falcon, H. R.; Marsella, G.; Martello, D.; Martinez Bravo, O.; Mathes, H. J.; Matthews, J.; Matthews, J. A. J.; Matthiae, G.; Maurizio, D.; Mazur, P. O.; Medina-Tanco, G.; Melissas, M.; Melo, D.; Menichetti, E.; Menshikov, A.; Meurer, C.; Micanovic, S.; Micheletti, M. I.; Miller, W.; Miramonti, L.; Mollerach, S.; Monasor, M.; Ragaigne, D. Monnier; Montanet, F.; Morales, B.; Morello, C.; Moreno, E.; Moreno, J. C.; Morris, C.; Mostafa, M.; Mueller, S.; Muller, M. A.; Mueller, G.; Muenchmeyer, M.; Mussa, R.; Navarra, G.; Navarro, J. L.; Navas, S.; Necesal, P.; Nellen, L.; Nhung, P. T.; Nierstenhoefer, N.; Nitz, D.; Nosek, D.; Nozka, L.; Nyklicek, M.; Oehlschlaeger, J.; Olinto, A.; Oliva, P.; Olmos-Gilbaja, V. M.; Ortiz, M.; Pacheco, N.; Pakk Selmi-Dei, D.; Palatka, M.; Pallotta, J.; Palmieri, N.; Parente, G.; Parizot, E.; Parra, A.; Parrisius, J.; Parsons, R. D.; Pastor, S.; Paul, T.; Pavlidou, V.; Payet, K.; Pech, M.; Pekala, J.; Pelayo, R.; Pepe, I. M.; Perrone, L.; Pesce, R.; Petermann, E.; Petrera, S.; Petrinca, P.; Petrolini, A.; Petrov, Y.; Petrovic, J.; Pfendner, C.; Phan, N.; Piegaia, R.; Pierog, T.; Pieroni, P.; Pimenta, M.; Pirronello, V.; Platino, M.; Ponce, V. H.; Pontz, M.; Privitera, P.; Prouza, M.; Quel, E. J.; Rautenberg, J.; Ravel, O.; Ravignani, D.; Revenu, B.; Ridky, J.; Riggi, S.; Risse, M.; Ristori, P.; Rivera, H.; Riviere, C.; Rizi, V.; Robledo, C.; Rodriguez, G.; Rodriguez Martino, J.; Rodriguez Rojo, J.; Rodriguez-Cabo, I.; Rodriguez-Frias, M. D.; Ros, G.; Rosado, J.; Rossler, T.; Roth, M.; Rouille-d'Orfeuil, B.; Roulet, E.; Rovero, A. C.; Salamida, F.; Salazar, H.; Salina, G.; Sanchez, F.; Santander, M.; Santo, C. E.; Santos, E.; Santos, E. M.; Sarazin, F.; Sarkar, S.; Sato, R.; Scharf, N.; Scherini, V.; Schieler, H.; Schiffer, P.; Schmidt, A.; Schmidt, F.; Schmidt, T.; Scholten, O.; Schoorlemmer, H.; Schovancova, J.; Schovanek, P.; Schroeder, F.; Schulte, S.; Schuessler, F.; Schuster, D.; Sciutto, S. J.; Scuderi, M.; Segreto, A.; Semikoz, D.; Settimo, M.; Shadkam, A.; Shellard, R. C.; Sidelnik, I.; Sigl, G.; Smialkowski, A.; Smida, R.; Snow, G. R.; Sommers, P.; Sorokin, J.; Spinka, H.; Squartini, R.; Stapleton, J.; Stasielak, J.; Stephan, M.; Strazzeri, E.; Stutz, A.; Suarez, F.; Suomijaervi, T.; Supanitsky, A. D.; Susa, T.; Sutherland, M. S.; Swain, J.; Szadkowski, Z.; Tamashiro, A.; Tapia, A.; Tarutina, T.; Tascau, O.; Tcaciuc, R.; Tcherniakhovski, D.; Tegolo, D.; Thao, N. T.; Thomas, D.; Tiffenberg, J.; Timmermans, C.; Tiwari, D. K.; Tkaczyk, W.; Todero Peixoto, C. J.; Tome, B.; Tonachini, A.; Travnicek, P.; Tridapalli, D. B.; Tristram, G.; Trovato, E.; Tueros, M.; Ulrich, R.; Unger, M.; Urban, M.; Valdes Galicia, J. F.; Valino, I.; Valore, L.; van den Berg, A. M.; Vargas Cardenas, B.; Vazquez, J. R.; Vazquez, R. A.; Veberic, D.; Venters, T.; Verzi, V.; Videla, M.; Villasenor, L.; Wahlberg, H.; Wahrlich, P.; Wainberg, O.; Warner, D.; Watson, A. A.; Weber, M.; Weidenhaupt, K.; Weindl, A.; Westerhoff, S.; Whelan, B. J.; Wieczorek, G.; Wiencke, L.; Wilczynska, B.; Wilczynski, H.; Will, M.; Williams, C.; Winchen, T.; Winders, L.; Winnick, M. G.; Wommer, M.; Wundheiler, B.; Yamamoto, T.; Younk, P.; Yuan, G.; Yushkov, A.; Zamorano, B.; Zas, E.; Zavrtanik, D.; Zavrtanik, M.; Zaw, I.; Zepeda, A.; Ziolkowski, M.; Martin, L.

    2011-01-01

    Since data-taking began in January 2004, the Pierre Auger Observatory has been recording the count rates of low energy secondary cosmic ray particles for the self-calibration of the ground detectors of its surface detector array. After correcting for atmospheric effects, modulations of galactic cosm

  19. Self-seeded operation of the LCLS hard X-ray FEL in the long-bunch mode

    CERN Document Server

    Geloni, Gianluca; Saldin, Evgeni

    2010-01-01

    Self-seeding options for the LCLS baseline were recently investigated using a scheme which relies on a single-crystal monochromator in Bragg-transmission geometry. The LCLS low-charge (0.02 nC) mode of operation was considered in order to demonstrate the feasibility of the proposed scheme. The wakefield effects from the linac and from the undulator vacuum chamber are much reduced at such low charge, and can be ignored. In this paper we extend our previous investigations to the case of the LCLS mode of operation with nominal charge. Based on the LCLS start-to-end simulation for an electron beam charge of 0.25 nC, and accounting for the wakefields from the undulator vacuum chamber we demonstrate that the same simplest self-seeding system (two undulators with a single-crystal monochromator in between) is appropriate not only for short (few femtosecond) bunches, but for longer bunches too.

  20. HYBRID Simulations of Diffraction-Limited Focusing with Kirkpatrick-Baez Mirrors for a Next-Generation In Situ Hard X-ray Nanoprobe

    Science.gov (United States)

    Maser, Jörg; Shi, Xianbo; Reininger, Ruben; Lai, Barry; Vogt, Stefan

    2016-12-01

    Next-generation hard X-ray nanoprobe beamlines such as the In Situ Nanoprobe (ISN) beamline being planned at the Advanced Photon Source aim at providing very high spatial resolution while also enabling very high focused flux, to study complex materials and devices using fast, multidimensional imaging across many length scales. The ISN will use diffractive optics to focus X-rays with a bandpass of ∆ E/ E = 10-4 into a focal spot of 20 nm or below. Reflective optics in Kirkpatrick-Baez geometry will be used to focus X-rays with a bandpass as large as ∆ E/ E = 10-2 into a focal spot of 50 nm. Diffraction-limited focusing with reflective optics is achieved by spatial filtering and use of a very long, vertically focusing mirror. To quantify the performance of the ISN beamline, we have simulated the propagation of both partially and fully coherent wavefronts from the undulator source, through the ISN beamline and into the mirror-based focal spot. Simulations were carried out using the recently developed software " HYBRID."

  1. HYBRID Simulations of Diffraction-Limited Focusing with Kirkpatrick-Baez Mirrors for a Next-Generation In Situ Hard X-ray Nanoprobe

    Science.gov (United States)

    Maser, Jörg; Shi, Xianbo; Reininger, Ruben; Lai, Barry; Vogt, Stefan

    2016-02-01

    Next-generation hard X-ray nanoprobe beamlines such as the In Situ Nanoprobe (ISN) beamline being planned at the Advanced Photon Source aim at providing very high spatial resolution while also enabling very high focused flux, to study complex materials and devices using fast, multidimensional imaging across many length scales. The ISN will use diffractive optics to focus X-rays with a bandpass of ∆E/E = 10-4 into a focal spot of 20 nm or below. Reflective optics in Kirkpatrick-Baez geometry will be used to focus X-rays with a bandpass as large as ∆E/E = 10-2 into a focal spot of 50 nm. Diffraction-limited focusing with reflective optics is achieved by spatial filtering and use of a very long, vertically focusing mirror. To quantify the performance of the ISN beamline, we have simulated the propagation of both partially and fully coherent wavefronts from the undulator source, through the ISN beamline and into the mirror-based focal spot. Simulations were carried out using the recently developed software "HYBRID."

  2. Measurements of the ablation-front trajectory and low-mode nonuniformity in direct-drive implosions using x-ray self-emission shadowgraphy

    Institute of Scientific and Technical Information of China (English)

    D.T.Michel; A.K.Davis; W.Armstrong; R.Bahr; R.Epstein; V.N.Goncharov; M.Hohenberger; I.V.Igumenshchev; R.Jungquist; D.D.Meyerhofer; P.B.Radha; T.C.Sangster; C.Sorce; D.H.Froula

    2015-01-01

    Self-emission x-ray shadowgraphy provides a method to measure the ablation-front trajectory and low-mode nonuniformity of a target imploded by directly illuminating a fusion capsule with laser beams. The technique uses time-resolved images of soft x-rays(>1 ke V) emitted from the coronal plasma of the target imaged onto an x-ray framing camera to determine the position of the ablation front. Methods used to accurately measure the ablation-front radius(δ R= ±1.15 μm), image-to-image timing(δ( t)= ±2.5 ps) and absolute timing(δt= ±10 ps) are presented.Angular averaging of the images provides an average radius measurement of δ( Rav)= ±0.15 μm and an error in velocity of δV / V= ±3%. This technique was applied on the Omega Laser Facility [Boehly et al., Opt. Commun. 133, 495(1997)] and the National Ignition Facility [Campbell and Hogan, Plasma Phys. Control. Fusion 41, B39(1999)].

  3. Parental and hybrid Daphnia from the D. longispina complex: long-term dynamics in genetic structure and significance of overwintering modes.

    Science.gov (United States)

    Griebel, J; Gießler, S; Yin, M; Wolinska, J

    2016-04-01

    In recent decades, hybridization has become a focus of attention because of its role in evolutionary processes. However, little is known about changes in genetic structure within and between parental species and hybrids over time. Here, we studied processes of genetic change in parental species and hybrids from the Daphnia longispina complex (Crustacea, Cladocera) over a period of six years across ten habitats. These cyclical parthenogens respond to fluctuating environments by switching from asexual to sexual reproduction. Importantly, sexually produced diapausing eggs, which resist extreme conditions such as low temperatures and serve as dispersal stages, are produced to a lower extent by hybrids. Long-term microsatellite data revealed clear differences between hybrids and parental species. In hybrids, clonal diversity values were lower, whereas heterozygosity and linkage disequilibrium values were higher compared to parental species. Clonal diversity of hybrids responded to the strength of the winter, with cold winters resulting in few genotypes in the following spring. In time windows when only asexual hybrid females survive, priority effects will favour the establishment of the hybrid offspring before hatchlings from parental diapause eggs can enter the community. The constant high levels of heterozygosity maintained by clonal reproduction in hybrids might lead to their successful establishment over time, when they are able to escape competition from both parental species. Although we found evidence that hybrids diversity depends on fluctuating environments, a direct link between hybrid abundance and the strength of winter was missing. Because of reduced adaptability in clonally reproducing hybrids, multiple factors must contribute to promoting their long-term success in fluctuating environments.

  4. SU-F-18C-13: Low-Dose X-Ray CT Reconstruction Using a Hybrid First-Order Method

    Energy Technology Data Exchange (ETDEWEB)

    Liu, L; Lin, W [Tianjin University, Tianjin (China); Jin, M [University of Texas at Arlington, Arlington, TX (United States)

    2014-06-15

    Purpose: To develop a novel reconstruction method for X-ray CT that can lead to accurate reconstruction at significantly reduced dose levels combining low X-ray incident intensity and few views of projection data. Methods: The noise nature of the projection data at low X-ray incident intensity was modeled and accounted by the weighted least-squares (WLS) criterion. The total variation (TV) penalty was used to mitigate artifacts caused by few views of data. The first order primal-dual (FOPD) algorithm was used to minimize TV in image domain, which avoided the difficulty of the non-smooth objective function. The TV penalized WLS reconstruction was achieved by alternated FOPD TV minimization and projection onto convex sets (POCS) for data fidelity constraints. The proposed FOPD-POCS method was evaluated using the FORBILD jaw phantom and the real cadaver head CT data. Results: The quantitative measures, root mean square error (RMSE) and contrast-to-noise ratio (CNR), demonstrate the superior denoising capability of WLS over LS-based TV iterative reconstruction. The improvement of RMSE (WLS vs. LS) is 15%∼21% and that of CNR is 17%∼72% when the incident counts per ray are ranged from 1×10{sup 5} to 1×10{sup 3}. In addition, the TV regularization can accurately reconstruct images from about 50 views of the jaw phantom. The FOPD-POCS reconstruction reveals more structural details and suffers fewer artifacts in both the phantom and real head images. The FOPD-POCS method also shows fast convergence at low X-ray incident intensity. Conclusion: The new hybrid FOPD-POCS method, based on TV penalized WLS, yields excellent image quality when the incident X-ray intensity is low and the projection views are limited. The reconstruction is computationally efficient since the FOPD minimization of TV is applied only in the image domain. The characteristics of FOPD-POCS can be exploited to significantly reduce radiation dose of X-ray CT without compromising accuracy for diagnosis

  5. A novel hybrid mode of sample injection to enhance CZE sensitivity for simultaneous determination of a pyridine-triphenylborane anti-fouling agent and its degradation products.

    Science.gov (United States)

    Kaewchuay, Netnapit; Yakushiji, Yuki; Fukushi, Keiichi; Saito, Keiitsu; Hirokawa, Takeshi

    2011-06-01

    We developed a novel hybrid sample injection mode (HSIM) that presents the combination of electrokinetic injection and vacuum injection to enhance detection sensitivity in CZE. Samples were introduced using both vacuum and electrokinetic injections simultaneously, with a water plug injected into the capillary prior to sample introduction (i.e. similarly to field-amplified sample injection, FASI). Using a sample mixture containing an anti-fouling agent applied to ship hulls, pyridine-triphenylborane and its degradation products (diphenylborinic acid, phenylboronic acid, and phenol) dissolved in ACN, the length of water plug, time, and voltage for sample introduction were optimized. The signal intensity (peak height) was found to be up to a 30-fold increased using HSIM by applying 4 kV for 4 s at the inlet end of the capillary as the cathode with supplementary vacuum in comparison with only vacuum injection for 4 s. The LODs (at a S/N of 3) for pyridine-triphenylborane, diphenylborinic acid, phenylboronic acid, and phenol were 0.88, 1.0, 21, and 23 μg/L, respectively. At the level of 0.04 mg/L, the RSDs (n=4, intra-day) for the above analytes were in the ranges of 1.9-11, 4.3-9.2, and 0.34-0.66% for peak area, peak height, and migration time, respectively. The HSIM is a simple and promising procedure useful for enhancing the sensitivity for both low-and high-mobility ions in CZE.

  6. Extended X-ray absorption fine structure studies of Zn2Fe2 hybrid hemoglobins: absence of heme bond length changes in half-ligated species.

    Science.gov (United States)

    Simolo, K; Korszun, Z R; Stucky, G; Moffat, K; McLendon, G; Bunker, G

    1986-07-01

    Metal hybrid hemoglobins, in which Zn(II) replaces Fe(II), have been structurally characterized by extended X-ray absorption structure (EXAFS) studies. Since Zn and Fe have very different K absorption edge energies, the structures of the ligated (Fe) and unligated (Zn) sites could be examined independently within a single molecule that mimics an intermediate ligation state. The observed EXAFS spectra and associated structural parameters are compared among the ligand free (alpha Zn)2(beta Zn)2, half-ligated (alpha FeCO)2(beta Zn)2 and (alpha Zn)2(beta FeCO)2, and fully ligated (alpha FeCO)2(beta FeCO)2 systems.

  7. Simulation results for PLATO: a prototype hybrid X-ray photon counting detector with a low energy threshold for fusion plasma diagnostics

    Science.gov (United States)

    Habib, A.; Menouni, M.; Pangaud, P.; Fenzi, C.; Colledani, G.; Moureau, G.; Escarguel, A.; Morel, C.

    2017-01-01

    PLATO is a prototype hybrid X-ray photon counting detector that has been designed to meet the specifications for plasma diagnostics for the WEST tokamak platform (Tungsten (W) Environment in Steady-state Tokamak) in southern France, with potential perspectives for ITER. PLATO represents a customized solution that fulfills high sensitivity, low dispersion and high photon counting rate. The PLATO prototype matrix is composed of 16 × 18 pixels with a 70 μm pixel pitch. New techniques have been used in analog sensitive blocks to minimize noise coupling through supply rails and substrate, and to suppress threshold dispersion across the matrix. The PLATO ASIC is designed in CMOS 0.13 μm technology and was submitted for a fabrication run in June 2016. The chip is designed to be bump-bonded to a silicon sensor. This paper presents pixel architecture as well as simulation results while highlighting novel solutions.

  8. A Hybrid Spin-Down Model and its Application to the Radio Quiet X-Ray Pulsar 1E 1207.4-5209

    Institute of Scientific and Technical Information of China (English)

    张灵娣; 彭秋和; 罗新炼

    2003-01-01

    A series of newly published papers are focusing on the formation of the absorption features discovered by Chandra and XMM-Newton from the young radio quiet x-ray pulsar 1E 1207.4-5209. We try to interpret it as cyclotron absorption lines since this possibility could not be ruled out. With new development and application of a hybrid model, i.e., the magnetic dipole spin-down model combined with the neutrino cyclotron radiation spin-down model, we can easily avoid the contradiction between the normal rotation energy loss rate and the relatively lower magnetic field, and then we obtain the possible initial spin period (~0.420s). We suppose that the progenitor of 1E 1207.4-5209 may be a white dwarf.

  9. sp2/sp3 hybridization ratio in amorphous carbon from C 1s core-level shifts: X-ray photoelectron spectroscopy and first-principles calculation

    Science.gov (United States)

    Haerle, Rainer; Riedo, Elisa; Pasquarello, Alfredo; Baldereschi, Alfonso

    2002-01-01

    Using a combined experimental and theoretical approach, we address C 1s core-level shifts in amorphous carbon. Experimental results are obtained by x-ray photoelectron spectroscopy (XPS) and electron-energy-loss spectroscopy (EELS) on thin-film samples of different atomic density, obtained by a pulsed-laser deposition growth process. The XPS spectra are deconvoluted into two contributions, which are attributed to sp2- and sp3-hybridized atoms, respectively, separated by 0.9 eV, independent of atomic density. The sp3 hybridization content extracted from XPS is consistent with the atomic density derived from the plasmon energy in the EELS spectrum. In our theoretical study, we generate several periodic model structures of amorphous carbon of different densities applying two schemes of increasing accuracy in sequence. We first use a molecular-dynamics approach, based on an environmental-dependent tight-binding Hamiltonian to quench the systems from the liquid phase. The final model structures are then obtained by further atomic relaxation using a first-principles pseudopotential plane-wave approach within density-functional theory. Within the latter framework, we also calculate carbon 1s core-level shifts for our disordered model structures. We find that the shifts associated to threefold- and fourfold- coordinated carbon atoms give rise to two distinct peaks separated by about 1.0 eV, independent of density, in close agreement with experimental observations. This provides strong support for decomposing the XPS spectra into two peaks resulting from sp2- and sp3-hybridized atoms. Core-hole relaxations effects account for about 30% of the calculated shifts.

  10. The exposure of the hybrid detector of the Pierre Auger Observatory

    NARCIS (Netherlands)

    Abreu, P.; Aglietta, M.; Ahn, E. J.; Allard, D.; Allekotte, I.; Allen, J.; Alvarez Castillo, J.; Alvarez-Muniz, J.; Ambrosio, M.; Aminaei, A.; Anchordoqui, L.; Andringa, S.; Anticic, T.; Anzalone, A.; Aramo, C.; Arganda, E.; Arisaka, K.; Arqueros, F.; Asorey, H.; Assis, P.; Aublin, J.; Ave, M.; Avenier, M.; Avila, G.; Baecker, T.; Badagnani, D.; Balzer, M.; Barber, K. B.; Barbosa, A. F.; Bardenet, R.; Barroso, S. L. C.; Baughman, B.; Beatty, J. J.; Becker, B. R.; Becker, K. H.; Belletoile, A.; Bellido, J. A.; BenZvi, S.; Berat, C.; Bergmann, T.; Bertou, X.; Biermann, P. L.; Billoir, P.; Blanco, F.; Blanco, M.; Bleve, C.; Bluemer, H.; Bohacova, M.; Boncioli, D.; Bonifazi, C.; Bonino, R.; Borodai, N.; Brack, J.; Brogueira, P.; Brown, W. C.; Bruijn, R.; Buchholz, P.; Bueno, A.; Burton, R. E.; Busca, N. G.; Caballero-Mora, K. S.; Caramete, L.; Caruso, R.; Castellina, A.; Catalano, O.; Cataldi, G.; Cazon, L.; Cester, R.; Chauvin, J.; Chiavassa, A.; Chinellato, J. A.; Chou, A.; Chudoba, J.; Clay, R. W.; Colombo, E.; Coluccia, M. R.; Conceicao, R.; Contreras, F.; Cook, H.; Cooper, M. J.; Coppens, J.; Cordier, A.; Cotti, U.; Coutu, S.; Covault, C. E.; Creusot, A.; Criss, A.; Cronin, J.; Curutiu, A.; Dagoret-Campagne, S.; Dallier, R.; Dasso, S.; Daumiller, K.; Dawson, B. R.; de Almeida, R. M.; De Domenico, M.; De Donato, C.; de Jong, S. J.; De La Vega, G.; de Mello Junior, W. J. M.; de Mello Neto, J. R. T.; De Mitri, I.; de Souza, V.; de Vries, K. D.; Decerprit, G.; del Peral, L.; Deligny, O.; Della Selva, A.; Dembinski, H.; Denkiewicz, A.; Di Giulio, C.; Diaz, J. C.; Diaz Castro, M. L.; Diep, P. N.; Dobrigkeit, C.; D'Olivo, J. C.; Dong, P. N.; Dorofeev, A.; dos Anjos, J. C.; Dova, M. T.; D'Urso, D.; Dutan, I.; Ebr, J.; Engel, R.; Erdmann, M.; Escobar, C. O.; Etchegoyen, A.; Luis, P. Facal San; Falcke, H.; Farrar, G.; Fauth, A. C.; Fazzini, N.; Ferguson, A. P.; Ferrero, A.; Fick, B.; Filevich, A.; Filipcic, A.; Fleck, I.; Fliescher, S.; Fracchiolla, C. E.; Fraenkel, E. D.; Froehlich, U.; Fuchs, B.; Fulgione, W.; Gamarra, R. F.; Gambetta, S.; Garcia, B.; Garcia Gamez, D.; Garcia-Pinto, D.; Garrido, X.; Gascon, A.; Gelmini, G.; Gemmeke, H.; Gesterling, K.; Ghia, P. L.; Giaccari, U.; Giller, M.; Glass, H.; Gold, M. S.; Golup, G.; Gomez Albarracin, F.; Gomez Berisso, M.; Goncalves, P.; Gonzalez, D.; Gonzalez, J. G.; Gookin, B.; Gora, D.; Gorgi, A.; Gouffon, P.; Gozzini, S. R.; Grashorn, E.; Grebe, S.; Grigat, M.; Grillo, A. F.; Guardincerri, Y.; Guarino, F.; Guedes, G. P.; Hague, J. D.; Hansen, P.; Harari, D.; Harmsma, S.; Harton, J. L.; Haungs, A.; Hebbeker, T.; Heck, D.; Herve, A. E.; Hojvat, C.; Holmes, V. C.; Homola, P.; Horandel, J. R.; Horneffer, A.; Hrabovsky, M.; Huege, T.; Insolia, A.; Ionita, F.; Italiano, A.; Jiraskova, S.; Kadija, K.; Kaducak, M.; Kampert, K. H.; Karhan, P.; Karova, T.; Kasper, P.; Kegl, B.; Keilhauer, B.; Keivani, A.; Kelley, J. L.; Kemp, E.; Kieckhafer, R. M.; Klages, H. O.; Kleifges, M.; Kleinfeller, J.; Knapp, J.; Koang, D. -H.; Kotera, K.; Krohm, N.; Kroemer, O.; Kruppke-Hansen, D.; Kuehn, F.; Kuempel, D.; Kulbartz, J. K.; Kunka, N.; La Rosa, G.; Lachaud, C.; Lautridou, P.; Leao, M. S. A. B.; Lebrun, D.; Lebrun, P.; Leigui de Oliveira, M. A.; Lemiere, A.; Letessier-Selvon, A.; Lhenry-Yvon, I.; Link, K.; Lopez, R.; Lopez Agueera, A.; Louedec, K.; Lozano Bahilo, J.; Lucero, A.; Ludwig, M.; Lyberis, H.; Maccarone, M. C.; Macolino, C.; Maldera, S.; Mandat, D.; Mantsch, P.; Mariazzi, A. G.; Marin, V.; Maris, I. C.; Marquez Falcon, H. R.; Marsella, G.; Martello, D.; Martinez Bravo, O.; Mathes, H. J.; Matthews, J.; Matthews, J. A. J.; Matthiae, G.; Maurizio, D.; Mazur, P. O.; McEwen, M.; Medina-Tanco, G.; Melissas, M.; Melo, D.; Menichetti, E.; Menshikov, A.; Meurer, C.; Micanovic, S.; Micheletti, M. I.; Miller, W.; Miramonti, L.; Mollerach, S.; Monasor, M.; Ragaigne, D. Monnier; Montanet, F.; Morales, B.; Morello, C.; Moreno, E.; Moreno, J. C.; Morris, C.; Mostafa, M.; Mueller, S.; Muller, M. A.; Muenchmeyer, M.; Mussa, R.; Navarra, G.; Navarro, J. L.; Navas, S.; Necesal, P.; Nellen, L.; Nhung, P. T.; Nierstenhoefer, N.; Nitz, D.; Nosek, D.; Nozka, L.; Nyklicek, M.; Oehlschlaeger, J.; Olinto, A.; Oliva, P.; Olmos-Gilbaja, V. M.; Ortiz, M.; Pacheco, N.; Pakk Selmi-Dei, D.; Palatka, M.; Pallotta, J.; Palmieri, N.; Parente, G.; Parizot, E.; Parra, A.; Parrisius, J.; Parsons, R. D.; Pastor, S.; Paul, T.; Pavlidou, V.; Payet, K.; Pech, M.; Pekala, J.; Pelayo, R.; Pepe, I. M.; Perrone, L.; Pesce, R.; Petermann, E.; Petrera, S.; Petrinca, P.; Petrolini, A.; Petrov, Y.; Petrovic, J.; Pfendner, C.; Phan, N.; Piegaia, R.; Pierog, T.; Pimenta, M.; Pirronello, V.; Platino, M.; Ponce, V. H.; Pontz, M.; Privitera, P.; Prouza, M.; Quel, E. J.; Rautenberg, J.; Ravel, O.; Ravignani, D.; Revenu, B.; Ridky, J.; Riggi, S.; Risse, M.; Ristori, P.; Rivera, H.; Riviere, C.; Rizi, V.; Robledo, C.; Rodriguez, G.; Rodriguez Martino, J.; Rodriguez Rojo, J.; Rodriguez-Cabo, I.; Rodriguez-Frias, M. D.; Ros, G.; Rosado, J.; Rossler, T.; Roth, M.; Rouille-d'Orfeuil, B.; Roulet, E.; Rovero, A. C.; Salamida, F.; Salazar, H.; Salina, G.; Sanchez, F.; Santander, M.; Santo, C. E.; Santos, E.; Santos, E. M.; Sarazin, F.; Sarkar, S.; Sato, R.; Scharf, N.; Scherini, V.; Schieler, H.; Schiffer, P.; Schmidt, A.; Schmidt, F.; Schmidt, T.; Scholten, O.; Schoorlemmer, H.; Schovancova, J.; Schovanek, P.; Schroeder, F.; Schulte, S.; Schuessler, F.; Schuster, D.; Sciutto, S. J.; Scuderi, M.; Segreto, A.; Semikoz, D.; Settimo, M.; Shadkam, A.; Shellard, R. C.; Sidelnik, I.; Sigl, G.; Smialkowski, A.; Smida, R.; Snow, G. R.; Sommers, P.; Sorokin, J.; Spinka, H.; Squartini, R.; Stapleton, J.; Stasielak, J.; Stephan, M.; Strazzeri, E.; Stutz, A.; Suarez, F.; Suomijaervi, T.; Supanitsky, A. D.; Susa, T.; Sutherland, M. S.; Swain, J.; Szadkowski, Z.; Tamashiro, A.; Tapia, A.; Tarutina, T.; Tascau, O.; Tcaciuc, R.; Tcherniakhovski, D.; Tegolo, D.; Thao, N. T.; Thomas, D.; Tiffenberg, J.; Timmermans, C.; Tiwari, D. K.; Tkaczyk, W.; Todero Peixoto, C. J.; Tome, B.; Tonachini, A.; Travnicek, P.; Tridapalli, D. B.; Tristram, G.; Trovato, E.; Tueros, M.; Ulrich, R.; Unger, M.; Urban, M.; Valdes Galicia, J. F.; Valino, I.; Valore, L.; van den Berg, A. M.; Vargas Cardenas, B.; Vazquez, J. R.; Vazquez, R. A.; Veberic, D.; Venters, T.; Verzi, V.; Videla, M.; Villasenor, L.; Wahlberg, H.; Wahrlich, P.; Wainberg, O.; Warner, D.; Watson, A. A.; Weidenhaupt, K.; Weinidl, A.; Westerhoff, S.; Whelan, B. J.; Wieczorek, G.; Wiencke, L.; Wilczynska, B.; Wilczynski, H.; Will, M.; Williams, C.; Winchen, T.; Winders, L.; Winnick, M. G.; Wommer, M.; Wundheiler, B.; Yamamoto, T.; Younk, P.; Yuan, G.; Yushkov, A.; Zamorano, B.; Zas, E.; Zavrtanik, D.; Zavrtanik, M.; Zaw, I.; Zepeda, A.; Ziolkowski, M.; Martin, L.

    2011-01-01

    The Pierre Auger Observatory is a detector for ultra-high energy cosmic rays. It consists of a surface array to measure secondary particles at ground level and a fluorescence detector to measure the development of air showers in the atmosphere above the array. The "hybrid" detection mode combines th

  11. The exposure of the hybrid detector of the Pierre Auger Observatory

    NARCIS (Netherlands)

    Abreu, P.; Aglietta, M.; Ahn, E. J.; Allard, D.; Allekotte, I.; Allen, J.; Alvarez Castillo, J.; Alvarez-Muniz, J.; Ambrosio, M.; Aminaei, A.; Anchordoqui, L.; Andringa, S.; Anticic, T.; Anzalone, A.; Aramo, C.; Arganda, E.; Arisaka, K.; Arqueros, F.; Asorey, H.; Assis, P.; Aublin, J.; Ave, M.; Avenier, M.; Avila, G.; Baecker, T.; Badagnani, D.; Balzer, M.; Barber, K. B.; Barbosa, A. F.; Bardenet, R.; Barroso, S. L. C.; Baughman, B.; Beatty, J. J.; Becker, B. R.; Becker, K. H.; Belletoile, A.; Bellido, J. A.; BenZvi, S.; Berat, C.; Bergmann, T.; Bertou, X.; Biermann, P. L.; Billoir, P.; Blanco, F.; Blanco, M.; Bleve, C.; Bluemer, H.; Bohacova, M.; Boncioli, D.; Bonifazi, C.; Bonino, R.; Borodai, N.; Brack, J.; Brogueira, P.; Brown, W. C.; Bruijn, R.; Buchholz, P.; Bueno, A.; Burton, R. E.; Busca, N. G.; Caballero-Mora, K. S.; Caramete, L.; Caruso, R.; Castellina, A.; Catalano, O.; Cataldi, G.; Cazon, L.; Cester, R.; Chauvin, J.; Chiavassa, A.; Chinellato, J. A.; Chou, A.; Chudoba, J.; Clay, R. W.; Colombo, E.; Coluccia, M. R.; Conceicao, R.; Contreras, F.; Cook, H.; Cooper, M. J.; Coppens, J.; Cordier, A.; Cotti, U.; Coutu, S.; Covault, C. E.; Creusot, A.; Criss, A.; Cronin, J.; Curutiu, A.; Dagoret-Campagne, S.; Dallier, R.; Dasso, S.; Daumiller, K.; Dawson, B. R.; de Almeida, R. M.; De Domenico, M.; De Donato, C.; de Jong, S. J.; De La Vega, G.; de Mello Junior, W. J. M.; de Mello Neto, J. R. T.; De Mitri, I.; de Souza, V.; de Vries, K. D.; Decerprit, G.; del Peral, L.; Deligny, O.; Della Selva, A.; Dembinski, H.; Denkiewicz, A.; Di Giulio, C.; Diaz, J. C.; Diaz Castro, M. L.; Diep, P. N.; Dobrigkeit, C.; D'Olivo, J. C.; Dong, P. N.; Dorofeev, A.; dos Anjos, J. C.; Dova, M. T.; D'Urso, D.; Dutan, I.; Ebr, J.; Engel, R.; Erdmann, M.; Escobar, C. O.; Etchegoyen, A.; Luis, P. Facal San; Falcke, H.; Farrar, G.; Fauth, A. C.; Fazzini, N.; Ferguson, A. P.; Ferrero, A.; Fick, B.; Filevich, A.; Filipcic, A.; Fleck, I.; Fliescher, S.; Fracchiolla, C. E.; Fraenkel, E. D.; Froehlich, U.; Fuchs, B.; Fulgione, W.; Gamarra, R. F.; Gambetta, S.; Garcia, B.; Garcia Gamez, D.; Garcia-Pinto, D.; Garrido, X.; Gascon, A.; Gelmini, G.; Gemmeke, H.; Gesterling, K.; Ghia, P. L.; Giaccari, U.; Giller, M.; Glass, H.; Gold, M. S.; Golup, G.; Gomez Albarracin, F.; Gomez Berisso, M.; Goncalves, P.; Gonzalez, D.; Gonzalez, J. G.; Gookin, B.; Gora, D.; Gorgi, A.; Gouffon, P.; Gozzini, S. R.; Grashorn, E.; Grebe, S.; Grigat, M.; Grillo, A. F.; Guardincerri, Y.; Guarino, F.; Guedes, G. P.; Hague, J. D.; Hansen, P.; Harari, D.; Harmsma, S.; Harton, J. L.; Haungs, A.; Hebbeker, T.; Heck, D.; Herve, A. E.; Hojvat, C.; Holmes, V. C.; Homola, P.; Horandel, J. R.; Horneffer, A.; Hrabovsky, M.; Huege, T.; Insolia, A.; Ionita, F.; Italiano, A.; Jiraskova, S.; Kadija, K.; Kaducak, M.; Kampert, K. H.; Karhan, P.; Karova, T.; Kasper, P.; Kegl, B.; Keilhauer, B.; Keivani, A.; Kelley, J. L.; Kemp, E.; Kieckhafer, R. M.; Klages, H. O.; Kleifges, M.; Kleinfeller, J.; Knapp, J.; Koang, D. -H.; Kotera, K.; Krohm, N.; Kroemer, O.; Kruppke-Hansen, D.; Kuehn, F.; Kuempel, D.; Kulbartz, J. K.; Kunka, N.; La Rosa, G.; Lachaud, C.; Lautridou, P.; Leao, M. S. A. B.; Lebrun, D.; Lebrun, P.; Leigui de Oliveira, M. A.; Lemiere, A.; Letessier-Selvon, A.; Lhenry-Yvon, I.; Link, K.; Lopez, R.; Lopez Agueera, A.; Louedec, K.; Lozano Bahilo, J.; Lucero, A.; Ludwig, M.; Lyberis, H.; Maccarone, M. C.; Macolino, C.; Maldera, S.; Mandat, D.; Mantsch, P.; Mariazzi, A. G.; Marin, V.; Maris, I. C.; Marquez Falcon, H. R.; Marsella, G.; Martello, D.; Martinez Bravo, O.; Mathes, H. J.; Matthews, J.; Matthews, J. A. J.; Matthiae, G.; Maurizio, D.; Mazur, P. O.; McEwen, M.; Medina-Tanco, G.; Melissas, M.; Melo, D.; Menichetti, E.; Menshikov, A.; Meurer, C.; Micanovic, S.; Micheletti, M. I.; Miller, W.; Miramonti, L.; Mollerach, S.; Monasor, M.; Ragaigne, D. Monnier; Montanet, F.; Morales, B.; Morello, C.; Moreno, E.; Moreno, J. C.; Morris, C.; Mostafa, M.; Mueller, S.; Muller, M. A.; Muenchmeyer, M.; Mussa, R.; Navarra, G.; Navarro, J. L.; Navas, S.; Necesal, P.; Nellen, L.; Nhung, P. T.; Nierstenhoefer, N.; Nitz, D.; Nosek, D.; Nozka, L.; Nyklicek, M.; Oehlschlaeger, J.; Olinto, A.; Oliva, P.; Olmos-Gilbaja, V. M.; Ortiz, M.; Pacheco, N.; Pakk Selmi-Dei, D.; Palatka, M.; Pallotta, J.; Palmieri, N.; Parente, G.; Parizot, E.; Parra, A.; Parrisius, J.; Parsons, R. D.; Pastor, S.; Paul, T.; Pavlidou, V.; Payet, K.; Pech, M.; Pekala, J.; Pelayo, R.; Pepe, I. M.; Perrone, L.; Pesce, R.; Petermann, E.; Petrera, S.; Petrinca, P.; Petrolini, A.; Petrov, Y.; Petrovic, J.; Pfendner, C.; Phan, N.; Piegaia, R.; Pierog, T.; Pimenta, M.; Pirronello, V.; Platino, M.; Ponce, V. H.; Pontz, M.; Privitera, P.; Prouza, M.; Quel, E. J.; Rautenberg, J.; Ravel, O.; Ravignani, D.; Revenu, B.; Ridky, J.; Riggi, S.; Risse, M.; Ristori, P.; Rivera, H.; Riviere, C.; Rizi, V.; Robledo, C.; Rodriguez, G.; Rodriguez Martino, J.; Rodriguez Rojo, J.; Rodriguez-Cabo, I.; Rodriguez-Frias, M. D.; Ros, G.; Rosado, J.; Rossler, T.; Roth, M.; Rouille-d'Orfeuil, B.; Roulet, E.; Rovero, A. C.; Salamida, F.; Salazar, H.; Salina, G.; Sanchez, F.; Santander, M.; Santo, C. E.; Santos, E.; Santos, E. M.; Sarazin, F.; Sarkar, S.; Sato, R.; Scharf, N.; Scherini, V.; Schieler, H.; Schiffer, P.; Schmidt, A.; Schmidt, F.; Schmidt, T.; Scholten, O.; Schoorlemmer, H.; Schovancova, J.; Schovanek, P.; Schroeder, F.; Schulte, S.; Schuessler, F.; Schuster, D.; Sciutto, S. J.; Scuderi, M.; Segreto, A.; Semikoz, D.; Settimo, M.; Shadkam, A.; Shellard, R. C.; Sidelnik, I.; Sigl, G.; Smialkowski, A.; Smida, R.; Snow, G. R.; Sommers, P.; Sorokin, J.; Spinka, H.; Squartini, R.; Stapleton, J.; Stasielak, J.; Stephan, M.; Strazzeri, E.; Stutz, A.; Suarez, F.; Suomijaervi, T.; Supanitsky, A. D.; Susa, T.; Sutherland, M. S.; Swain, J.; Szadkowski, Z.; Tamashiro, A.; Tapia, A.; Tarutina, T.; Tascau, O.; Tcaciuc, R.; Tcherniakhovski, D.; Tegolo, D.; Thao, N. T.; Thomas, D.; Tiffenberg, J.; Timmermans, C.; Tiwari, D. K.; Tkaczyk, W.; Todero Peixoto, C. J.; Tome, B.; Tonachini, A.; Travnicek, P.; Tridapalli, D. B.; Tristram, G.; Trovato, E.; Tueros, M.; Ulrich, R.; Unger, M.; Urban, M.; Valdes Galicia, J. F.; Valino, I.; Valore, L.; van den Berg, A. M.; Vargas Cardenas, B.; Vazquez, J. R.; Vazquez, R. A.; Veberic, D.; Venters, T.; Verzi, V.; Videla, M.; Villasenor, L.; Wahlberg, H.; Wahrlich, P.; Wainberg, O.; Warner, D.; Watson, A. A.; Weidenhaupt, K.; Weinidl, A.; Westerhoff, S.; Whelan, B. J.; Wieczorek, G.; Wiencke, L.; Wilczynska, B.; Wilczynski, H.; Will, M.; Williams, C.; Winchen, T.; Winders, L.; Winnick, M. G.; Wommer, M.; Wundheiler, B.; Yamamoto, T.; Younk, P.; Yuan, G.; Yushkov, A.; Zamorano, B.; Zas, E.; Zavrtanik, D.; Zavrtanik, M.; Zaw, I.; Zepeda, A.; Ziolkowski, M.; Martin, L.

    2011-01-01

    The Pierre Auger Observatory is a detector for ultra-high energy cosmic rays. It consists of a surface array to measure secondary particles at ground level and a fluorescence detector to measure the development of air showers in the atmosphere above the array. The "hybrid" detection mode combines th

  12. X-ray dose detector based on color changing of light-emitting polymer–metal complex hybrid material.

    OpenAIRE

    2012-01-01

    We report on the design, fabrication and performance of a poly (2-methoxy-5(2_-ethylhexyloxy)- p-phenylenevinylene)/tris-(8-hydroxyquinoline)aluminum (MEH-PPV/Alq3) X-ray dose detector for improving safety for cancer patients shortly before radiation therapy. The detector consists of an inexpen-sive (

  13. Inelastic X-ray scattering of a transition-metal complex (FeCl4(-)): vibrational spectroscopy for all normal modes.

    Science.gov (United States)

    Dong, Weibing; Wang, Hongxin; Olmstead, Marilyn M; Fettinger, James C; Nix, Jay; Uchiyama, Hiroshi; Tsutsui, Satoshi; Baron, Alfred Q R; Dowty, Eric; Cramer, Stephen P

    2013-06-17

    The tetraethylammonium salt of the transition-metal complex FeCl4(-) has been examined using inelastic X-ray scattering (IXS) with 1.5 meV resolution (12 cm(-1)) at 21.747 keV. This sample serves as a feasibility test for more elaborate transition-metal complexes. The IXS spectra were compared with previously recorded IR, Raman, and nuclear resonant vibrational spectroscopy (NRVS) spectra, revealing the same normal modes but with less strict selection rules. Calculations with a previously derived Urey-Bradley force field were used to simulate the expected Q and orientation dependence of the IXS intensities. The relative merits of IXS, compared to other photon-based vibrational spectroscopies such as NRVS, Raman, and IR, are discussed.

  14. A Vertical Resonances of G-Mode Oscillations in Warped Disks and QPOs in Low-Mass X-Ray Binaries

    CERN Document Server

    Kato, S

    2005-01-01

    Resonant oscillations in warped disks are examined in order to explain high-frequency QPOs and horizontal-branch QPOs in low-mass X-ray binaries. Different from our previous work, addressed to the same subjects, we relax in this paper the assumption that the disks are isothermal in the vertical direction. That is, the pressure, density, and temperature are assumed to be distributed in the vertical direction with a polytropic relation, and the polytropic index changes as the disk state changes. By this generalization and by some subsidiaries we can qualitatively explain, within the framework of our resonance model, observed large frequency variations in neutron-star QPOs and little variations in black-hole QPOs. We consider vertical resonances of g-mode oscillations, since they are most appropriate to explain observations.

  15. Temperature variation of ultralow frequency modes and mean square displacements in solid lasamide (diuretic drug) studied by 35Cl-NQR, X-ray and DFT/QTAIM.

    Science.gov (United States)

    Latosińska, Jolanta Natalia; Latosińska, Magdalena; Kasprzak, Jerzy; Tomczak, Magdalena; Maurin, Jan Krzysztof

    2012-10-25

    The application of combined (35)Cl-NQR/X-ray/DFT/QTAIM methods to study the temperature variation of anisotropic displacement parameters and ultralow frequency modes of anharmonic torsional vibrations in the solid state is illustrated on the example of 2,4-dichloro-5-sulfamolybenzoic acid (lasamide, DSBA) which is a diuretic and an intermediate in the synthesis of furosemide and thus its common impurity. The crystallographic structure of lasamide is solved by X-ray diffraction and refined to a final R-factor of 3.06% at room temperature. Lasamide is found to crystallize in the triclinic space group P-1, with two equivalent molecules in the unit cell a = 7.5984(3) Å, b = 8.3158(3) Å, c = 8.6892(3) Å; α = 81.212(3)°, β = 73.799(3)°, γ = 67.599(3)°. Its molecules form symmetric dimers linked by two short and linear intermolecular hydrogen bonds O-H···O (O-H···O = 2.648 Å and ∠OHO = 171.5°), which are further linked by weaker and longer intermolecular hydrogen bonds N-H···O (N-H···O = 2.965 Å and ∠NHO = 166.4°). Two (35)Cl-NQR resonance frequencies, 36.899 and 37.129 MHz, revealed at room temperature are assigned to chlorine sites at the ortho and para positions, relative to the carboxyl functional group, respectively. The difference in C-Cl(1) and C-Cl(2) bond lengths only slightly affects the value of (35)Cl-NQR frequencies, which results mainly from chemical inequivalence of chlorine atoms but also involvement in different intermolecular interactions pattern. The smooth decrease in both (35)Cl-NQR frequencies with increasing temperature in the range of 77-300 K testifies to the averaging of EFG tensor at each chlorine site due to anharmonic torsional vibrations. Lasamide is thermally stable; no temperature-induced release of chlorine or decomposition of this compound is detected. The temperature dependence of ultralow frequency modes of anharmonic small-angle internal torsional vibrations averaging EFG tensor and mean square angle

  16. Simulation on advanced operation mode for the compact fusion-fission hybrid reactor%紧凑型聚变裂变混合堆先进运行模式的数值模拟

    Institute of Scientific and Technical Information of China (English)

    陈美霞; 刘成岳; 吴斌

    2012-01-01

    Reversed shear (RS) operation mode is simulated with Jsolver and TSC codes on some important issues, such as RS Plasma configuration, bootstrap current fraction and RS operation mode discharge simulation etc.. To some degree, the modeling results show that the RS operation mode is advanced and feasible for the compact Fusion-fission hybrid reactor.%使用Jsolver程序及托卡马克模拟程序TSC对紧凑型聚变裂变混合堆系统的反剪切平衡位形、自举电流份额及放电模拟进行数值模拟研究,以此探讨该混合堆的可行性和先进性.

  17. Monte Carlo Simulations of High-speed, Time-gated MCP-based X-ray Detectors: Saturation Effects in DC and Pulsed Modes and Detector Dynamic Range

    Energy Technology Data Exchange (ETDEWEB)

    Craig Kruschwitz, Ming Wu, Ken Moy, Greg Rochau

    2008-10-31

    We present here results of continued efforts to understand the performance of microchannel plate (MCP)–based, high-speed, gated, x-ray detectors. This work involves the continued improvement of a Monte Carlo simulation code to describe MCP performance coupled with experimental efforts to better characterize such detectors. Our goal is a quantitative description of MCP saturation behavior in both static and pulsed modes. We have developed a new model of charge buildup on the walls of the MCP channels and measured its effect on MCP gain. The results are compared to experimental data obtained with a short-pulse, high-intensity ultraviolet laser; these results clearly demonstrate MCP saturation behavior in both DC and pulsed modes. The simulations compare favorably to the experimental results. The dynamic range of the detectors in pulsed operation is of particular interest when fielding an MCP–based camera. By adjusting the laser flux we study the linear range of the camera. These results, too, are compared to our simulations.

  18. Ultrasoft 1.5 keV aluminum K X rays are efficient producers of complex chromosome exchange aberrations as revealed by fluorescence in situ hybridization.

    Science.gov (United States)

    Griffin, C S; Stevens, D L; Savage, J R

    1996-08-01

    The electron pairs generated by ultrasoft 1.5 keV aluminum K X-ray photons deposit their energy in tracks of length < 70 nm and provide an ideal tool for analyzing the spatial distribution of breaks and misrepair processes. We have undertaken the analysis of changes in chromosome structure produced by aluminum K X rays in untransformed HF12 human fibroblasts in G1 phase using fluorescence in situ hybridization (FISH). Multicolored chromosome-specific DNA probes for chromosomes 1 and 2 and an alpha-satellite pan-centromeric probe were used to examine in vitro radiation-induced chromosome-type exchange aberrations. After mean doses of 0.37-2.93 Gy the relative frequencies of complex exchanges, derived from three or more breaks in two or more chromosomes, ranged from 15-35%. For the classic break-age-and-rejoining theory to hold, very large interaction distances are needed to account for this high frequency of multibreak interactions, unless many sites pre-exist where several different chromosomes come very close together. Alternatively, damaged DNA may be able to interact with adjacent undamaged DNA, obviating the need for large rejoining distances.

  19. Operating modes and cooling capabilities of the 3-stage ADR developed for the Soft-X-ray Spectrometer instrument on Astro-H

    Science.gov (United States)

    Shirron, Peter J.; Kimball, Mark O.; James, Bryan L.; Muench, Theodore; DiPirro, Michael J.; Letmate, Richard V.; Sampson, Michael A.; Bialas, Tom G.; Sneiderman, Gary A.; Porter, Frederick S.; Kelley, Richard L.

    2016-03-01

    A 3-stage adiabatic demagnetization refrigerator (ADR) (Shirron et al., 2012) is used on the Soft X-ray Spectrometer instrument (Mitsuda et al., 2010) on Astro-H (Takahashi et al., 2010) [3] to cool a 6 × 6 array of X-ray microcalorimeters to 50 mK. The ADR is supported by a cryogenic system (Fujimoto et al., 2010) consisting of a superfluid helium tank, a 4.5 K Joule-Thomson (JT) cryocooler, and additional 2-stage Stirling cryocoolers that pre-cool the JT cooler and cool radiation shields within the cryostat. The ADR is configured so that it can use either the liquid helium or the JT cryocooler as its heat sink, giving the instrument an unusual degree of tolerance for component failures or degradation in the cryogenic system. The flight detector assembly, ADR and dewar were integrated into the flight dewar in early 2014, and have since been extensively characterized and calibrated. This paper summarizes the operation and performance of the ADR in all of its operating modes.

  20. Modelling the Ohmic L-mode ramp-down phase of JET hybrid pulses using JETTO with Bohm-gyro-Bohm transport

    Science.gov (United States)

    Bizarro, João P. S.; Köchl, Florian; Voitsekhovitch, Irina; EFDA Contributors, JET

    2016-11-01

    The empirical Bohm-gyro-Bohm (BgB) transport model implemented in the JETTO code is used to predictively simulate the purely Ohmic (OH), L-mode current-ramp-down phase of three JET hybrid pulses, which combine two different ramp rates with two different electron densities (at the beginning of the ramp). The modelling is discussed, namely the strategy to reduce as much as possible the number of free parameters used to benchmark the model predictions against the experimental results. Hence, keeping the gas puffing rate as measured whilst controlling the line-averaged electron density via the recycling coefficient (which in the modelling is taken at the separatrix instead of the wall), one of the many possible ways to fix the total particle source, it is shown that the BgB model reproduces well the experimental data, as far as both average quantities (plasma internal inductance and volume-averaged electron temperature) and profiles (electron density and temperature) are concerned, with relative errors remaining mostly below 20 % . The sensitivenesses with respect to the recycling coefficient, the ion effective charge, the energy of neutrals entering the plasma through the separatrix and the need to introduce a particle pinch are assessed; the necessity for a proper sawtooth model if experimental results are to be reproduced is also shown. The strong non-linear coupling in a OH plasma between density, temperature and current (essentially via interplay between the power-balance equation, Joule’s heating with a temperature-dependent resistivity and the dependence of BgB transport coefficients on profile gradients) is put in evidence and analyzed in light of modelling results. It is still inferred from the modelling that the real value of the recycling coefficient at the separatrix (basically, the so-called fuelling efficiency times the actual recycling coefficient at the wall) must become close to one in the final stages of the discharges, when the gas puffing is

  1. One-pot preparation of mercaptotetrazole-silica hybrid monoliths by the thiol-ene click reaction for mixed-mode capillary liquid chromatography.

    Science.gov (United States)

    Wang, Haojiang; Hu, Wenli; Zheng, Qiong; Bian, Wei; Lin, Zian

    2017-06-01

    A novel mercaptotetrazole-silica hybrid monolithic column was prepared for capillary liquid chromatography, in which the thiol-end mercaptotetrazole was mixed with hydrolyzed γ-methacryloxypropyltrimethoxysilane and tetramethyloxysilane for the co-polycondensation and thiol-ene click reaction in a one-pot process. The effects of the molar ratio of silanes, the amount of mercaptotetrazole, and the volume of porogen on the morphology, permeability and pore properties of the as-prepared mercaptotetrazole-silica hybrid monoliths were investigated in detail. A series of test compounds including alkylbenzenes, amides and anilines were employed for evaluating the retention behaviors of the mercaptotetrazole-silica hybrid monolithic columns. The results demonstrated that the mercaptotetrazole-silica hybrid monoliths exhibited hydrophobic, hydrophilic as well as ion-exchange interaction. The run-to-run, column-to-column and batch-to-batch reproducibilities of the mercaptotetrazole-silica hybrid monoliths were satisfactory with the relative standard deviations less than 1.4 (n = 5), 3.9 (n = 3) and 4.0% (n = 5), respectively. In addition, the mercaptotetrazole-silica hybrid monolith was further applied to the separation of sulfonamides, nucleobases and protein tryptic digests. These successful applications confirmed the promising potential of the mercaptotetrazole-silica hybrid monolith in the separation of complex samples. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. 离网型风光互补发电系统多模态能量控制与管理%Multi-Mode Energy Control and Management for Stand-Alone Wind-Photovoltaic Hybrid Power System

    Institute of Scientific and Technical Information of China (English)

    皇甫宜耿; 安晓彤; 马瑞卿; 骆光照

    2013-01-01

      离网型风光互补发电系统是一种合理配置新能源的独立电源系统,由于自然界中风能、太阳能出现的不可预测性,以及负载、储能状态的随机性,提出一种基于风光互补发电系统多模态能量流的分析法,研究了各模态及模态间转化特性,给出了四种典型状态下风光互补发电系统的能量控制及管理。采用闭环电压控制使风力发电通道和光伏发电通道输出电压恒定,为用电设备和储能元件提供安全可靠的电能。通过 MATLAB /Simulink 软件对离网型风光互补发电系统多模态能量控制进行了仿真,结果表明离网型风光互补发电系统工作可靠,验证了多模态分析法的有效性。%A Stand-alone wind-photovoltaic hybrid power system allocates new energy resources reasonably and in -dependently.But the appearance of wind energy and solar energy is unpredictable , and their loading and storage states are random.Therefore, we analyze the flow of the multi-mode energy of the stand -alone wind-photovoltaic hy-brid power system.We study its mode and modal transformation and then control and manage the energy in its four typical modes.We use the closed-loop voltage control to make sure that the output voltage of a wind turbine and the photovoltaic-generated power are stable and that the power supply for electrical equipment and electricity -storage components is safe and reliable.We use the MATLAB /Simulink to simulate the control of the multi -mode energy of the stand-alone wind-photovoltaic hybrid power system .The simulation results, give in Figs.4, 5 and 6, and their analysis show preliminarily that the stand -alone wind-photovoltaic hybrid power system can work reliably , verifying that our multi-mode analysis method is effective .

  3. HYBRID VEHICLE CONTROL SYSTEM

    Directory of Open Access Journals (Sweden)

    V. Dvadnenko

    2016-06-01

    Full Text Available The hybrid vehicle control system includes a start–stop system for an internal combustion engine. The system works in a hybrid mode and normal vehicle operation. To simplify the start–stop system, there were user new possibilities of a hybrid car, which appeared after the conversion. Results of the circuit design of the proposed system of basic blocks are analyzed.

  4. One-pot preparation of glutathione-silica hybrid monolith for mixed-mode capillary liquid chromatography based on "thiol-ene" click chemistry.

    Science.gov (United States)

    Lin, Zian; Tan, Xiaoqing; Yu, Ruifang; Lin, Jiashi; Yin, Xiaofei; Zhang, Lan; Yang, Huanghao

    2014-08-15

    A novel glutathione (GSH)-silica hybrid monolithic column synthesized via a combination of thiol-ene click reaction and one-pot process was described, where thiol-end GSH organic monomer and 2,2-azobisisobutyronitrile (AIBN) were mixed with hydrolyzed tetramethyloxysilane (TMOS) and γ-methacryloxypropyltrimethoxysilane (γ-MAPS) and then introduced into a fused-silica capillary for simultaneous polycondensation and "thiol-ene" click reaction to form the GSH-silica hybrid monolith. The effects of the molar ratio of TMOS/γ-MAPS, the amount of GSH, and the volume of porogen on the morphology, permeability and pore properties of the prepared GSH-silica hybrid monoliths were studied in detail. A uniform monolithic network with high porosity was obtained. A series of test compounds including alkylbenzenes, amides, and anilines were used to evaluate the retention behaviors of the GSH-silica hybrid monolithic column. The results demonstrated that the prepared GSH-silica hybrid monolith exhibited multiple interactions including hydrophobicity, hydrophilicity, as well as cation exchange interaction. The run-to-run, column-to-column and batch-to-batch reproducibilities of the GSH-silica hybrid monolith for phenols' retention were satisfactory with the relative standard deviations (RSDs) less than 1.3% (n=5), 2.6% (n=3) and 3.2% (n=3), respectively, indicating the effectiveness and practicability of the proposed method. In addition, the GSH-silica hybrid monolith was applied to the separation of nucleotides, peptides and protein tryptic digests, respectively. The successful applications suggested the potential of the GSH-silica hybrid monolith in complex sample analysis.

  5. 双模式风光互补发电系统结构研究%Research on Structure of Photovoltaic and Wind Hybrid Generation System with Dual-Mode

    Institute of Scientific and Technical Information of China (English)

    吴威; 张吉; 崔琛; 范秋杰; 张帆

    2012-01-01

    介绍了小型风光互补发电系统的运行原理,分析了并网型和离网型系统的常用结构,并针对系统离网运行可能存在的极端情况,提出一种双模式智能切换运行的风光互补系统结构,实现智能离/并网运行功能,引入双向电能表,记录电能在系统与电网间的双向流动,实现新能源发电在电力市场的流通,对风光互补发电系统的研究提供了一定的借鉴作用。%Introduction was made to the operational principle of photovoltaic and wind hybrid generation system. Analysis was made to the common structures of grid-on and grid-off systems. This paper raised a kind of photovoltaic and wind hybrid generation system with dual-mode, which could change the grid-on and grid-off mode intelligently under extreme conditions. What is more, a dual-direction electric meter was used to record the mutual power flow between hybrid system and grid, which aimed to imply the new power generation in the flow of the electricity market, providing a reference for the research ofphotovoltaic and wind hybrid generation system.

  6. Ordering in bio-inorganic hybrid nanomaterials probed by in situ scanning transmission X-ray microscopy

    Science.gov (United States)

    Lee, Jonathan R. I.; Bagge-Hansen, Michael; Tunuguntla, Ramya; Kim, Kyunghoon; Bangar, Mangesh; Willey, Trevor M.; Tran, Ich C.; Kilcoyne, David A.; Noy, Aleksandr; van Buuren, Tony

    2015-05-01

    Phospholipid bilayer coated Si nanowires are one-dimensional (1D) composites that provide versatile bio-nanoelectronic functionality via incorporation of a wide variety of biomolecules into the phospholipid matrix. The physiochemical behaviour of the phospholipid bilayer is strongly dependent on its structure and, as a consequence, substantial modelling and experimental efforts have been directed at the structural characterization of supported bilayers and unsupported phospholipid vesicles; nonetheless, the experimental studies conducted to date have exclusively involved volume-averaged techniques, which do not allow for the assignment of spatially resolved structural variations that could critically impact the performance of the 1D phospholipid-Si NW composites. In this manuscript, we use scanning transmission X-ray microscopy (STXM) to probe bond orientation and bilayer thickness as a function of position with a spatial resolution of ~30 nm for Δ9-cis 1,2-dioleoyl-sn-glycero-3-phosphocholine layers prepared Si NWs. When coupled with small angle X-ray scattering measurements, the STXM data reveal structural motifs of the Si NWs that give rise to multi-bilayer formation and enable assignment of the orientation of specific bonds known to affect the order and rigidity of phospholipid bilayers.Phospholipid bilayer coated Si nanowires are one-dimensional (1D) composites that provide versatile bio-nanoelectronic functionality via incorporation of a wide variety of biomolecules into the phospholipid matrix. The physiochemical behaviour of the phospholipid bilayer is strongly dependent on its structure and, as a consequence, substantial modelling and experimental efforts have been directed at the structural characterization of supported bilayers and unsupported phospholipid vesicles; nonetheless, the experimental studies conducted to date have exclusively involved volume-averaged techniques, which do not allow for the assignment of spatially resolved structural

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

    Science.gov (United States)

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

    2014-12-01

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

  8. Mobile, hybrid Compton/coded aperture imaging for detection, identification and localization of gamma-ray sources at stand-off distances

    Science.gov (United States)

    Tornga, Shawn R.

    The Stand-off Radiation Detection System (SORDS) program is an Advanced Technology Demonstration (ATD) project through the Department of Homeland Security's Domestic Nuclear Detection Office (DNDO) with the goal of detection, identification and localization of weak radiological sources in the presence of large dynamic backgrounds. The Raytheon-SORDS Tri-Modal Imager (TMI) is a mobile truck-based, hybrid gamma-ray imaging system able to quickly detect, identify and localize, radiation sources at standoff distances through improved sensitivity while minimizing the false alarm rate. Reconstruction of gamma-ray sources is performed using a combination of two imaging modalities; coded aperture and Compton scatter imaging. The TMI consists of 35 sodium iodide (NaI) crystals 5x5x2 in3 each, arranged in a random coded aperture mask array (CA), followed by 30 position sensitive NaI bars each 24x2.5x3 in3 called the detection array (DA). The CA array acts as both a coded aperture mask and scattering detector for Compton events. The large-area DA array acts as a collection detector for both Compton scattered events and coded aperture events. In this thesis, developed coded aperture, Compton and hybrid imaging algorithms will be described along with their performance. It will be shown that multiple imaging modalities can be fused to improve detection sensitivity over a broader energy range than either alone. Since the TMI is a moving system, peripheral data, such as a Global Positioning System (GPS) and Inertial Navigation System (INS) must also be incorporated. A method of adapting static imaging algorithms to a moving platform has been developed. Also, algorithms were developed in parallel with detector hardware, through the use of extensive simulations performed with the Geometry and Tracking Toolkit v4 (GEANT4). Simulations have been well validated against measured data. Results of image reconstruction algorithms at various speeds and distances will be presented as well as

  9. 混合系统故障诊断的模态转换自适应阈值研究%Mode-Dependent Thresholds for Fault Diagnosis and Identification of a Hybrid System

    Institute of Scientific and Technical Information of China (English)

    黄磊; 史仪凯; 袁小庆; 苏士斌

    2014-01-01

    混合系统是既有连续变量也有离散事件的复杂的动力学系统,混合系统中的模态转换及参数不确定性可引起残差突变,原因是不同的模态下有不同的元件参与,采用常数阈值或常规自适应阈值往往造成误诊和漏诊。通过搭建混合系统键合图诊断模型,在对参数不确定性进行区间估计的基础上,运用线性分式转换构造模态转换自适应阈值,解决混合系统故障诊断中的误诊和漏诊问题。通过车辆转向系统的故障诊断进行实例分析及检验,实验结果表明所提算法的正确性和可行性,为混合系统故障诊断提供了新的解决方案。%A hybrid system is a complex dynamics system that includes both continuous variables and discrete e-vents;mode changes and component uncertainties lead to different compositions of component uncertainties and re-sidual fluctuations;the employment of constant threshold will cause false alarm or missed detection on hybrid fault detection system. In this paper, we, taking component parameter uncertainties and mode change into consideration, utilize Global Analytical Redundancy Relations ( GARR) and LFT Bond Graph model to formulate mode-dependent thresholds to address problems of false alarm or missed detection in FDI of a hybrid system. An online experiment of vehicle steering system is researched in detail to show the concepts of the proposed algorithm, and experimental re-sults of different faults suggest the feasibility of mode-dependent threshold in FDI of a hybrid system.

  10. The solvent shell structure of aqueous iodide: X-ray absorption spectroscopy and classical, hybrid QM/MM and full quantum molecular dynamics simulations

    Energy Technology Data Exchange (ETDEWEB)

    Pham, V.T. [Ecole Polytechnique Federale de Lausanne, Laboratoire de spectroscopie ultrarapide, ISIC, FSB-BSP, CH-1015 Lausanne (Switzerland); Tavernelli, I. [Ecole Polytechnique Federale de Lausanne, Laboratoire de chimie et biochimie computationnelles, ISIC, FSB-BSP, CH-1015 Lausanne (Switzerland); Milne, C.J.; van der Veen, R.M. [Ecole Polytechnique Federale de Lausanne, Laboratoire de spectroscopie ultrarapide, ISIC, FSB-BSP, CH-1015 Lausanne (Switzerland); D' Angelo, P. [Dipartimento di Chimica, Universita di Roma ' La Sapienza' , Ple A. Moro 5, 00185 Roma (Italy); Bressler, Ch. [Ecole Polytechnique Federale de Lausanne, Laboratoire de spectroscopie ultrarapide, ISIC, FSB-BSP, CH-1015 Lausanne (Switzerland); Chergui, M., E-mail: Majed.Chergui@epfl.ch [Ecole Polytechnique Federale de Lausanne, Laboratoire de spectroscopie ultrarapide, ISIC, FSB-BSP, CH-1015 Lausanne (Switzerland)

    2010-05-25

    Graphical abstract: The L{sub 3}-edge EXAFS spectra of aqueous iodide are compared to classical, QM/MM and DFT-based molecular dynamics simulations. The QM/MM simulations reproduce best the experimental data. An anisotropy of the solvation shell is also identified. - Abstract: The L{sub 3} X-ray absorption spectrum of aqueous iodide is reported, and its EXAFS is compared to theoretical spectra reconstructed from the radial distribution function of the iodide hydration obtained from classical, hybrid Quantum Mechanics Molecular Mechanics, (QM/MM) and full quantum (density functional theory, DFT) molecular dynamics simulations. Since EXAFS is mainly sensitive to short distances around the iodide ion, it is a direct probe of the local solvation structure. The comparison shows that QM/MM simulations deliver a satisfactory description of the EXAFS signal, while nonpolarizable classical simulations are somewhat less satisfactory and DFT-based simulations perform poorly. We also identify a weak anisotropy of the water solvation shell around iodide, which may be of importance in electron photoejection experiments.

  11. PEGylated hybrid ytterbia nanoparticles as high-performance diagnostic probes for in vivo magnetic resonance and X-ray computed tomography imaging with low systemic toxicity.

    Science.gov (United States)

    Liu, Zhen; Pu, Fang; Liu, Jianhua; Jiang, Liyan; Yuan, Qinghai; Li, Zhengqiang; Ren, Jinsong; Qu, Xiaogang

    2013-05-21

    Novel nanoparticulate contrast agents with low systemic toxicity and inexpensive character have exhibited more advantages over routinely used small molecular contrast agents for the diagnosis and prognosis of disease. Herein, we designed and synthesized PEGylated hybrid ytterbia nanoparticles as high-performance nanoprobes for X-ray computed tomography (CT) imaging and magnetic resonance (MR) imaging both in vitro and in vivo. These well-defined nanoparticles were facile to prepare and cost-effective, meeting the criteria as a biomedical material. Compared with routinely used Iobitridol in clinic, our PEG-Yb2O3:Gd nanoparticles could provide much significantly enhanced contrast upon various clinical voltages ranging from 80 kVp to 140 kVp owing to the high atomic number and well-positioned K-edge energy of ytterbium. By the doping of gadolinium, our nanoparticulate contrast agent could perform perfect MR imaging simultaneously, revealing similar organ enrichment and bio-distribution with the CT imaging results. The super improvement in imaging efficiency was mainly attributed to the high content of Yb and Gd in a single nanoparticle, thus making these nanoparticles suitable for dual-modal diagnostic imaging with a low single-injection dose. In addition, detailed toxicological study in vitro and in vivo indicated that uniformly sized PEG-Yb2O3:Gd nanoparticles possessed excellent biocompatibility and revealed overall safety.

  12. Binding mode of CA074, a specific irreversible inhibitor, to bovine cathepsin B as determined by X-ray crystal analysis of the complex.

    Science.gov (United States)

    Yamamoto, A; Hara, T; Tomoo, K; Ishida, T; Fujii, T; Hata, Y; Murata, M; Kitamura, K

    1997-05-01

    The binding mode of CA074 [N-(L-3-trans-propylcarbamoyl-oxirane-2-carbonyl)-L-isoleucyl-L-pr oline], a specific irreversible inhibitor, to bovine spleen cathepsin B was elucidated by X-ray crystal structure analysis of the complex at 2.2 A resolution (conventional R=0.185). Inconsistently with our model used for the development of CA074, the L-isoleucyl-L-proline and propylcarbamoyl moieties are located at the S' and S subsites, respectively. This unexpected binding is primarily due to (i) similar extended chain conformations (due to the same S configurations) at the oxirane C2 and C3 atoms of CA074 and (ii) the just fit formation of double hydrogen bonds between the carboxyl oxygens of L-proline and the imidazole nitrogens of His-110 and His-111 residues (these residues are missing in papain, the tertiary structure of which was used for the design of CA074). The oxirane C3 atom possessing the P' substituent is covalently bound to the Cys-29 Sgamma atom (C3-Sgamma=1.79 A) and the S configuration is maintained. The present result will provide useful information for characterizing the substrate-specificity of cathepsin B.

  13. Gamma-ray mutagenesis studies in a new human-hamster hybrid, A(L)CD59(+/-), which has two human chromosomes 11 but is hemizygous for the CD59 gene

    Science.gov (United States)

    Kraemer, S. M.; Vannais, D. B.; Kronenberg, A.; Ueno, A.; Waldren, C. A.; Chatterjee, A. (Principal Investigator)

    2001-01-01

    Kraemer, S. M., Vannais, D. B., Kronenberg, A., Ueno, A. and Waldren, C. A. Gamma-Ray Mutagenesis Studies in a New Human-Hamster Hybrid, A(L)CD59(+/-), which has Two Human Chromosomes 11 but is Hemizygous for the CD59 Gene. Radiat. Res. 156, 10-19 (2001).We have developed a human-CHO hybrid cell line, named A(L)CD59(+/-), which has two copies of human chromosome 11 but is hemizygous for the CD59 gene and the CD59 cell surface antigen that it encodes. Our previous studies used the A(L) and A(L)C hybrids that respectively contain one or two sets of CHO chromosomes plus a single copy of human chromosome 11. The CD59 gene at 11p13.5 and the CD59 antigen encoded by it are the principal markers used in our mutagenesis studies. The hybrid A(L)CD59(+/-) contains two copies of human chromosome 11, only one of which carries the CD59 gene. The incidence of CD59 (-) mutants (formerly called S1(-)) induced by (137)Cs gamma rays is about fivefold greater in A(L)CD59(+/-) cells than in A(L) cells. Evidence is presented that this increase in mutant yield is due to the increased induction of certain classes of large chromosomal mutations that are lethal to A(L) cells but are tolerated in the A(L)CD59(+/-) hybrid. In addition, significantly more of the CD59 (-) mutants induced by (137)Cs gamma rays in A(L)CD59(+/-) cells display chromosomal instability than in A(L) cells. On the other hand, the yield of gamma-ray-induced CD59 (-) mutants in A(L)CD59(+/-) cells is half that of the A(L)C hybrid, which also tolerates very large mutations but has only one copy of human chromosome 11. We interpret the difference in mutability as evidence that repair processes involving the homologous chromosomes 11 play a role in determining mutant yields. The A(L)CD59(+/-) hybrid provides a useful new tool for quantifying mutagenesis and shedding light on mechanisms of genetic instability and mutagenesis.

  14. The RBE of 3.4 MeV alpha-particles and 0.565 MeV neutrons relative to 60Co gamma-rays for neoplastic transformation of human hybrid cells and the impact of culture conditions.

    Science.gov (United States)

    Frankenberg-Schwager, M; Spieren, S; Pralle, E; Giesen, U; Brede, H J; Thiemig, M; Frankenberg, D

    2010-01-01

    The neoplastic transformation of human hybrid CGL1 cells is affected by perturbations from external influences such as serum batch and concentration, the number of medium changes during the 21-day expression period and cell seeding density. Nevertheless, for doses up to 1.5 Gy, published transformation frequencies for low linear energy transfer (LET) radiations (gamma-rays, MeV electrons or photons) are in good agreement, whereas for higher doses larger variations are reported. The (60)Co gamma-ray data here for doses up to 1.5 Gy, using a low-yield serum batch and only one medium change, are in agreement with published frequencies of neoplastic transformation of human hybrid cells. For 3.4 MeV alpha-particles (LET = 124 keV/mum) and 0.565 MeV monoenergetic neutrons relative to low doses of (60)Co gamma-rays, a maximum relative biological effectiveness (RBE(M)) of 2.8 +/- 0.2 and 1.5 +/- 0.2, respectively, was calculated. Surprisingly, at higher doses of (60)Co gamma-rays lower frequencies of neoplastic transformation were observed. This non-monotonic dose relationship for neoplastic transformation by (60)Co gamma-rays is likely due to the lack of a G2/M arrest observed at low doses resulting in higher transformation frequencies per dose, whereas the lower frequencies per dose observed for higher doses are likely related to the induction of a G2/M arrest.

  15. Simulation Study on PTH Mode of Diesel-Electric Hybrid Propulsion System%柴-电混合动力系统应急推进模式仿真研究

    Institute of Scientific and Technical Information of China (English)

    周庆波; 艾钢; 赵同宾; 金锋

    2011-01-01

    Power take me home (PTH) mode is motor single propulsion and it makes ship much safer. Simulation study on PTH mode of diesel-electric hybrid propulsion ship based on AMESim, control the clutch engage pressure achieve soft engagement and study on pitch of CPP load methods to make the ship start. The simulation results can be used as reference and direction of diesel-electric hybrid propulsion ship's PTH propulsion system design.%柴-电混合动力的应急推进( PTH)模式是将轴带电机作为电动机单独推进,增加了船舶的安全性.应用AMESim软件,对柴-电混合动力船舶的应急推进模式进行建模和仿真,研究通过,控制离合器接排压力实现柔性接排,以及调距桨螺距加载方法实现顺利起航,仿真结果可为柴-电混合动力船舶应急推进系统设计提供参考和指导.

  16. Short-term precision assessment of trabecular bone score and bone mineral density using dual-energy X-ray absorptiometry with different scan modes: an in vivo study

    Energy Technology Data Exchange (ETDEWEB)

    Bandirali, Michele; Poloni, Alessandro; Messina, Carmelo; Petrini, Marcello [Universita degli Studi di Milano, Scuola di Specializzazione in Radiodiagnostica, Milano (Italy); Sconfienza, Luca Maria; Sardanelli, Francesco [Unita di Radiologia, IRCCS Policlinico San Donato, San Donato Milanese (Italy); Universita degli Studi di Milano, Dipartimento di Scienze Biomediche per la Salute, San Donato Milanese (Italy); Papini, Giacomo Davide Edoardo; Di Leo, Giovanni [Unita di Radiologia, IRCCS Policlinico San Donato, San Donato Milanese (Italy); Ulivieri, Fabio Massimo [IRCCS Fondazione Ca' Granda Ospedale Maggiore Policlinico, Mineralometria Ossea Computerizzata e Ambulatorio Malattie Metabolismo Minerale e Osseo, Servizio di Medicina Nucleare, Milano (Italy)

    2015-07-15

    We estimated the in vivo reproducibility of trabecular bone score (TBS) from dual-energy X-ray absorptiometry (DXA) using different imaging modes to be compared to that of bone mineral density (BMD). We enrolled 30 patients for each imaging mode: fast-array, array, high definition. Each patient underwent two DXA examinations with in-between repositioning. BMD and TBS were obtained according to the International Society for Clinical Densitometry guidelines. The coefficient of variation (CoV) was calculated as the ratio between root mean square standard deviation and mean, percent least significant change (LSC) as 2.77 x CoV, reproducibility as the complement to 100 % LSC. Fast-array imaging mode resulted in 0.8 % CoV and 2.1 % LSC for BMD, 1.9 % and 5.3 % for TBS, respectively; array imaging mode resulted in 0.7 % and 2.0 % for BMD, 1.9 % and 5.2 %, for TBS; high-definition imaging mode resulted in 0.7 % and 2.0 %, for BMD; 2.0 % and 5.4 % for TBS, respectively. Reproducibility of TBS (95 %) was significantly lower than that of BMD (98 %) (p < 0.012). Difference in reproducibility among the imaging modes was not significant for either BMD or TBS (p = 0.942). While TBS reproducibility was significantly lower than that of BMD, differences among imaging modes were not significant for both TBS and BMD. (orig.)

  17. Binding mode characterization of NBD series CD4-mimetic HIV-1 entry inhibitors by X-ray structure and resistance study.

    Science.gov (United States)

    Curreli, Francesca; Kwon, Young Do; Zhang, Hongtao; Yang, Yongping; Scacalossi, Daniel; Kwong, Peter D; Debnath, Asim K

    2014-09-01

    We previously identified two small-molecule CD4 mimetics--NBD-556 and NBD-557--and synthesized a series of NBD compounds that resulted in improved neutralization activity in a single-cycle HIV-1 infectivity assay. For the current investigation, we selected several of the most active compounds and assessed their antiviral activity on a panel of 53 reference HIV-1 Env pseudoviruses representing diverse clades of clinical isolates. The selected compounds inhibited tested clades with low-micromolar potencies. Mechanism studies indicated that they act as CD4 agonists, a potentially unfavorable therapeutic trait, in that they can bind to the gp120 envelope glycoprotein and initiate a similar physiological response as CD4. However, one of the compounds, NBD-09027, exhibited reduced agonist properties, in both functional and biophysical studies. To understand the binding mode of these inhibitors, we first generated HIV-1-resistant mutants, assessed their behavior with NBD compounds, and determined the X-ray structures of two inhibitors, NBD-09027 and NBD-10007, in complex with the HIV-1 gp120 core at ∼2-Å resolution. Both studies confirmed that the NBD compounds bind similarly to NBD-556 and NBD-557 by inserting their hydrophobic groups into the Phe43 cavity of gp120. The basic nitrogen of the piperidine ring is located in close proximity to D368 of gp120 but it does not form any H-bond or salt bridge, a likely explanation for their nonoptimal antagonist properties. The results reveal the structural and biological character of the NBD series of CD4 mimetics and identify ways to reduce their agonist properties and convert them to antagonists. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

  18. A Coordinated Control for Photovoltaic Generators and Energy Storages in Low-Voltage AC/DC Hybrid Microgrids under Islanded Mode

    DEFF Research Database (Denmark)

    Liu, Yao; Hou, Xiaochao; Wang, Xiaofeng;

    2016-01-01

    The increasing penetration of renewable generators can be a significant challenge due to the fluctuation of their power generation. Energy storage (ES) units are one solution to improve power supply quality and guarantee system stability. In this paper, a hybrid microgrid is built based...... on photovoltaic (PV) generator and ES; and coordinated control is proposed and developed to achieve power management in a decentralized manner. This control scheme contains three different droop strategies according to characteristics of PV and ES. First, the modified droop control is proposed for PV, which can...... for alternating current (AC)-side ES. Thus, the ES lifetime is prolonged. Moreover, interlinking converters (ICs) provide a bridge between AC/DC buses in a hybrid microgrid. The power control of IC is enabled when the AC- or DC-side suffer from active power demand shortage. In particular, if the AC microgrid does...

  19. Dispersion Relation Tool for generalized lower-hybrid mode with, density gradient, equilibrium ExB drift, collisions and finite electron Larmor radius

    CERN Document Server

    Romadanov, Ivan; Frias, Winston; Chapurin, Oleksandr; Koshkarov, Oleksandr

    2016-01-01

    MATLAB solver has been developed for studies of local instabilities in partially magnetized plasmas typical for ExB discharge plasmas. Examples for the Simon-Hoh, lower-hybrid and ion-sound instabilities in Penning discharge. The detailed behavior of the local dispersion relation can be investigated, plotted and saved with this solver. It allows to include various effects, change plasma parameters and obtain eigen-frequencies as a function of the wavenumbers in x or y directions.

  20. Structure factor of blends of solvent-free nanoparticle–organic hybrid materials: density-functional theory and small angle X-ray scattering

    KAUST Repository

    Yu, Hsiu-Yu

    2014-09-15

    © the Partner Organisations 2014. We investigate the static structure factor S(q) of solvent-free nanoparticle-organic hybrid materials consisting of silica nanocores and space-filling polyethylene glycol coronas using a density-functional theory and small angle X-ray scattering measurements. The theory considers a bidisperse suspension of hard spheres with different radii and tethered bead-spring oligomers with different grafting densities to approximate the polydispersity effects in experiments. The experimental systems studied include pure samples with different silica core volume fractions and the associated mean corona grafting densities, and blends with different mixing ratios of the pure samples, in order to introduce varying polydispersity of corona grafting density. Our scattering experiments and theory show that, compared to the hard-sphere suspension with the same core volume fraction, S(q) for pure samples exhibit both substantially smaller values at small q and stronger particle correlations corresponding to a larger effective hard core at large q, indicating that the tethered incompressible oligomers enforce a more uniform particle distribution, and the densely grafted brush gives rise to an additional exclusionary effect between the nanoparticles. According to the theory, polydispersity in the oligomer grafting density controls the deviation of S(q) from the monodisperse system at smaller q, and the interplay of the enhanced effective core size and the entropic attraction among the particles is responsible for complex variations in the particle correlations at larger q. The successful comparison between the predictions and the measurements for the blends further suggests that S(q) can be used to assess the uniformity of grafting density in polymer-grafted nanoparticle materials. This journal is

  1. The comparison between the dose mode and the standard mode in molybdenum-rhodium target X-ray mammography%钼铑双靶乳腺X线摄影剂量优先模式与标准模式对照研究

    Institute of Scientific and Technical Information of China (English)

    王海阔; 周剑; 张妍; 杨蓉; 房丽蕊

    2015-01-01

    Objective To investigate the value of the dose mode (giving priority to dose reduction)of molybdenum-rhodium tar-get X-ray photography in mammary gland low-dose examination.Methods Fourty patients with breast cancer were recruited,and their bilateral mammographic images were respectively acquired by the standard modes and the dose modes in both CC and MLO po-sition using molybdenum-rhodium target X-ray machine.The total of 1 60 mammograms were obtained and analyzed in order to as-sess the images quality.The values of average glandular dose (AGD)and entrance skin exposure (ESE)on each patient were detec-ted and recorded respectively.Results The higher quality of images were guaranteed in both the standard modes and the dose modes.There was no significant difference in two mammographic modes (χ2 =0.427,P >0.05).Compared with the standard mode, X-ray exposure such as AGD and ESE values were reduced by 28.63% and 28.28% in CC position,and 26.33% and 29.43% in MLO position respectively for the dose mode.The paired t-test results showed that the differences of radiation exposure in AGD and ESE between the dose mode and the standard mode were all statistically significant (P0.05)。与标准模式相比,剂量优先模式摄影 CC 位 AGD 值降低约28.63%,ESE 值降低约28.28%,两者间具有显著性差异(t AGD =12.928,P <0.05,t ESE =8.850,P <0.05);MLO 位 AGD 值降低约26.33%,ESE 值降低约29.43%,两者间具有显著性差异(t AGD =11.006,P <0.05,t ESE =8.400,P <0.05)。结论在获取同等乳腺图像质量的情况下,钼铑双靶乳腺 X 射线摄影检查中剂量优先模式较标准模式能够有效降低受检者的辐射剂量。

  2. 光伏-储能联合发电系统运行机理及控制策略%Operating modes of photovoltaic/energy-storage hybrid system and its control strategy

    Institute of Scientific and Technical Information of China (English)

    梁亮; 李建林; 惠东

    2011-01-01

    对光伏-储能联合发电系统的运行模式进行了研究,包括整体运行模式、储能旁路模式、储能独立运行模式.提出光伏-储能联合发电系统的拓扑结构和潮流定向控制策略.基于某100 kWp光伏发电站的实际历史运行数据,进行了仿真验证,通过配备储能系统,增加了系统的可控性和可观性,实现对电网的友好接入;同时改善了系统输出特性,实现部分程度的“削峰填谷”,大幅降低光伏微网系统对电网输电容量的需求.%The operating modes of photovoltaic/energy-storage hybrid system are analyzed,including whole system mode,energy storage bypass mode and energy storage support mode. Its topology is proposed with the flow direction control, which is verified by the simulation with the operational data of a 100 kWp photovoltaic system. The integration of photovoltaic system and energy storage system increases the system controllability and grid-connection flexibility, improves the system output characteristics of load response,and reduces greatly the system requirements for grid power transmission capacity.

  3. Observation of a new turbulence-driven limit-cycle state in H-modes with lower hybrid current drive and lithium-wall conditioning in the EAST superconducting tokamak

    DEFF Research Database (Denmark)

    Wang, H.Q.; Xu, G.S.; Guo, H.Y.;

    2012-01-01

    -frequency oscillation, termed a limit-cycle state, appears at the edge during the quiescent phase with good energy and particle confinement. Detailed measurements by edge Langmuir probes show modulation interaction and strong three-wave coupling between the low-frequency oscillations and high-frequency-broadband (80......The first high confinement H-mode plasma has been obtained in the Experimental Advanced Superconducting Tokamak (EAST) with about 1 MW lower hybrid current drive after wall conditioning by lithium evaporation and real-time injection of Li powder. Following the L–H transition, a small-amplitude, low....... And the measurements demonstrate that the energy gain of zonal flows is of the same order as the energy loss of turbulence. This strongly suggests the interactions between zonal flows and high-frequency turbulences at the pedestal during the limit-cycle state....

  4. Short-term precision assessment of trabecular bone score and bone mineral density using dual-energy X-ray absorptiometry with different scan modes: an in vivo study.

    Science.gov (United States)

    Bandirali, Michele; Poloni, Alessandro; Sconfienza, Luca Maria; Messina, Carmelo; Papini, Giacomo Davide Edoardo; Petrini, Marcello; Ulivieri, Fabio Massimo; Di Leo, Giovanni; Sardanelli, Francesco

    2015-07-01

    We estimated the in vivo reproducibility of trabecular bone score (TBS) from dual-energy X-ray absorptiometry (DXA) using different imaging modes to be compared to that of bone mineral density (BMD). We enrolled 30 patients for each imaging mode: fast-array, array, high definition. Each patient underwent two DXA examinations with in-between repositioning. BMD and TBS were obtained according to the International Society for Clinical Densitometry guidelines. The coefficient of variation (CoV) was calculated as the ratio between root mean square standard deviation and mean, percent least significant change (LSC) as 2.77 × CoV, reproducibility as the complement to 100% LSC. Fast-array imaging mode resulted in 0.8% CoV and 2.1% LSC for BMD, 1.9% and 5.3% for TBS, respectively; array imaging mode resulted in 0.7% and 2.0% for BMD, 1.9% and 5.2%, for TBS; high-definition imaging mode resulted in 0.7% and 2.0%, for BMD; 2.0% and 5.4% for TBS, respectively. Reproducibility of TBS (95%) was significantly lower than that of BMD (98%) (p < 0.012). Difference in reproducibility among the imaging modes was not significant for either BMD or TBS (p = 0.942). While TBS reproducibility was significantly lower than that of BMD, differences among imaging modes were not significant for both TBS and BMD. • TBS is an emerging tool for assessing BMD. • TBS reproducibility is lower than that of BMD. • Differences between imaging modes are not significant for either TBS or BMD.

  5. A Coordinated Control for Photovoltaic Generators and Energy Storages in Low-Voltage AC/DC Hybrid Microgrids under Islanded Mode

    Directory of Open Access Journals (Sweden)

    Yao Liu

    2016-08-01

    Full Text Available The increasing penetration of renewable generators can be a significant challenge due to the fluctuation of their power generation. Energy storage (ES units are one solution to improve power supply quality and guarantee system stability. In this paper, a hybrid microgrid is built based on photovoltaic (PV generator and ES; and coordinated control is proposed and developed to achieve power management in a decentralized manner. This control scheme contains three different droop strategies according to characteristics of PV and ES. First, the modified droop control is proposed for PV, which can take full utilization of renewable energy and avoid regulating output active power frequently. Second, to maintain the direct current (DC bus voltage stability, a novel droop control incorporating a constant power band is presented for DC-side ES. Third, a cascade droop control is designed for alternating current (AC-side ES. Thus, the ES lifetime is prolonged. Moreover, interlinking converters (ICs provide a bridge between AC/DC buses in a hybrid microgrid. The power control of IC is enabled when the AC- or DC-side suffer from active power demand shortage. In particular, if the AC microgrid does not satisfy the reactive power demand, IC then acts as a static synchronous compensator (STATCOM. The effectiveness of the proposed strategies is verified by simulations.

  6. 农区不同品种肉羊杂交组合模式效益分析%Benefit analysis of different breeds of meat sheep hybrid combination mode in agricultural areas

    Institute of Scientific and Technical Information of China (English)

    唐家

    2012-01-01

    选择波尔山羊、南江黄羊、本地羊进行杂交组合,分析不同组合模式的产羔数、初生重、双月龄断奶重、六月龄出栏重等生产指标,筛选农区适度规模舍饲肉羊的最优杂交组合。结果表明:不同品种肉羊杂交生产性能明显提高:不同杂交组合模式效益依次为本♀×波♂×波♂〉本♀×南♂×波♂〉本♀×波♂。%Select the Boer goat, nanjiang, local sheep crossbreeding combinations, Analysis of different patterns of litter, Birth weight ,Two -months -weaning weight ,June slaughter age production index. Screening appropriate scale in agricultural areas feeding optimal hybrid combinations of mutton sheepo Results showed that: Different breeds of sheep crossbreeding of productive can significantly improve; Different hybrid modes benefit in order to Local sheep ♀×Boer goat ♂×Boer goat ♂〉Local sheep ♀×nanjiang ♂×Boer goat ♂〉Local sheep ♀×Boer goat ♂〉Local sheep ♀ ×nanjiang ♂〉Local sheep ♀× xLoeal sheep ♂ o

  7. 单模复合功率分流混合动力系统结构优化%Structure Optimization of SingleMode Compound Split Hybrid Power Train

    Institute of Scientific and Technical Information of China (English)

    杜爱民; 刘开圣; 朱忠攀; 王晨

    2015-01-01

    针对混合动力汽车中的动力耦合系统,提出一种双行星排结构的单模复合功率分流装置。通过对几种方案机械点的特性进行分析,筛选得出最优结构。对行星排特征参数进行优化,并推导得出满足结构限制的参数条件范围,在此基础上分析系统的工作模式和控制策略,最终利用离线仿真对该方案进行验证。%Based on a power coupling system in hybrid vehicles,a novel singlemode compound split power train with the structure of double- row planetary gear sets was proposed.An optimized structure was obtained by analyzing the mechanical points.Then the range of characteristic parameter of the planetary gear set was calculated and optimized.Operating modes and control strategy were anaG lyzed based on this optimized structure.The effectiveness of this hybrid system was finally validated by the simulation.

  8. Study of lower hybrid wave propagation and absorption in a tokamak plasma using hard X-Ray tomography; Etude de la propagation et de l'absorption de l'onde hybride dans un plasma de tokamak par tomographie X haute energie

    Energy Technology Data Exchange (ETDEWEB)

    Imbeaux, F

    1999-09-22

    Control of the current density profile is a critical issue in view to obtain high fusion performances in tokamak plasmas? It is therefore important to be able to control the power deposition profile of the lower hybrid wave, which has the highest current drive efficiency among all other non-inductive additional methods. Propagation and absorption of this wave are investigated in the Tore Supra tokamak using a new hard x-ray tomographic system and a new ray-tracing/Fokker-Planck code. These tools are described in detail and allow to analyse the lower hybrid power deposition profile dependence as a function of various plasma parameters (density, magnetic field, current) and of the injected wave spectrum. A good agreement between the code and the measurements found when the central electron temperature is greater than about 3 keV, that is in regimes where the wave undergoes only a few reflections before being absorbed. The simulations are then used to interpret the experimental trends. The lower hybrid power deposition profile is in nearly all discharges localised at a normalised minor radius of 0.2-0.3, and is weakly sensitive to variations of plasma parameters. It is hence difficult to perform an efficient control of the current profile generated by the lower hybrid wave in Tore Supra. This goal may nevertheless be reached by using an original method, which uses an auxiliary lower hybrid wave injected by a vertical port of the torus. This method is investigated by means of the simulation code. (author)

  9. An ionic 2D inorganic-organic hybrid of tris[((1H-tetrazol-5-yl)methyl)morpholine] dodecatungstophosphate(Ⅴ) pentahydrate:Synthesis X-ray crystal structure and spectroscopic characterizations

    Institute of Scientific and Technical Information of China (English)

    Mohsen; Nikpour; Hossein; Eshtiagh-Hosseini; Masoud; Mirzaei; Amir; Aghaei; Kaju; Soroush; Zarinabadi

    2010-01-01

    A unique ionic hybrid material[C_6H_(12)N_5O]_3[(PO_4)W__(12)O_(36)]·5H_2O has been synthesized from the reaction of((1H-tetrazole-5- yl)methyl)morpholine andα-H_3[(PO_4)W_(12)O_(36)]·21H_2O.It has successfully been characterized by elemental analysis,IR and ~1H NMR spectroscopies,TGA and single-crystal X-ray diffraction method.The title compound is constructed from the three [C_6H_(12)N_5O]~+ cations andα-Keggin[(PO_4)W_(12)O_(36)]~(3-) polyoxoanion.The most remarkable structural feature of this hybrid ...

  10. An evaluation of the new compact hybrid photodiodes R7110U-07/40 from Hamamatsu in high-speed light detection mode

    CERN Document Server

    Mirzoyan, R; Lorenz, E

    2000-01-01

    The main parameters of hybrid photodiodes (HPD) are constantly improving. In the new 20 mm diameter HPDs from Hamamatsu an avalanche diode (AD) serves as anode. Due to high gain of the used ADs the HPDs show a total gain of 6-8x10 sup 4 at nominal HV. This allows one to use HPDs with very fast low-noise voltage amplifiers and to detect fast pulses (down to the single photoelectron level) with very good amplitude resolution. Of special interest are HPDs of the type R7110U-40 with GaAsP photocathode which provide a quantum efficiency of approx 40% in maximum at approx 500 nm. Results on the evaluation of the above-mentioned HPDs and their comparison with HPDs from INTEVAC will be presented.

  11. Metropolitian area network services comprised of virtual local area networks running over hybrid fiber-coax and asynchronous transfer mode technologies

    Science.gov (United States)

    Biedron, William S.

    1995-11-01

    Since 1990 there has been a rapid increase in the demand for communication services, especially local and wide area network (LAN/WAN) oriented services. With the introduction of the DFB laser transmitter, hybrid-fiber-coax (HFC) cable plant designs, ATM transport technologies and rf modems, new LAN/WAN services can now be defined and marketed to residential and business customers over existing cable TV systems. The term metropolitan area network (MAN) can be used to describe this overall network. This paper discusses the technical components needed to provision these services as well as provides some perspectives on integration issues. Architecture at the headend and in the backbone is discussed, as well as specific service definitions and the technology issues associated with each. The TCP/IP protocol is suggested as a primary protocol to be used throughout the MAN.

  12. 基于滑模变结构PI控制的光伏系统MPPT研究%Novel hybrid control of MPPT method based on sliding mode variable structure and PI strategy

    Institute of Scientific and Technical Information of China (English)

    靳艳华; 惠晶; 谢伟

    2014-01-01

    Based on the analysis results of the photovoltaic power generation model and its output character, the proposed control er of sliding mode variable structure based on improved Zeta converter was proposed to realize Maximum Power Point Tracking (MPPT) of photovoltaic system. In order to obtain the optimized maximum power point control, the novel hybrid control of the Sliding Mode Variable Structure with variable switch parameter and PI strategy were presented. By comparing traditional P&O method with the proposed method by simulation and experiment, the good characters of the proposed method were verified.%在分析光伏电池的数学模型和输出特性基础上,给出基于改进的Zeta电路的滑模变结构控制策略。为实现光伏系统最大功率点跟踪(MPPT)的优化控制,提出可变阀值切换的滑模变结构+PI复合控制策略,实现了最大功率跟踪的优化控制。通过仿真与实验结果分析,并将给出的控制策略与广泛应用的扰动观测MPPT策略进行比较,验证了本控制策略具有良好的特性。

  13. 短波射线追踪技术中的电离层混合建模方法%Ionosphere hybrid modeling method for short-wave ray tracing

    Institute of Scientific and Technical Information of China (English)

    栗伟珉; 苏东林; 阎照文; 刘焱

    2012-01-01

    在国际参考电离层模型和多层准抛物模型的基础上,提出了一种混合应用两种模型进行电离层建模的新方法.利用射线追踪技术,分别对混合模型和传统国际参考电离层模型下短波射线在电离层中的轨迹进行了仿真,得到了电波群路径.通过与实测电波群路径的对比,结果表明:对中国中纬度地区在电离层混合模型下的射线追踪精度优于传统国际参考电离层模型下的射线追踪精度,同时混合建模方法降低了多层准抛物模型对输入条件的要求,扩展了多层准抛物模型在射线追踪技术中的应用范围.%Based on the international reference ionosphere(IRI) and the quasi-parabolic segments(QPS) model,a new ionosphere hybrid modeling method for short-wave ray tracing was proposed.The group ranges which show the short-wave propagation trace in the ionosphere were obtained separately by simulation in the hybrid model and the IRI model.By comparing the simulated results and the ionospheric oblique incidence sounding experimental data,the hybrid modeling method accuracy at mid-latitude region in China was analyzed.It indicates the ray tracing simulation accuracy in the hybrid model on experimental day better than the one in the IRI model.The limit to the QPS model's input is reduced by the hybrid modeling method and the QPS model's application range is extended in ray tracing technology.

  14. 程控X线机控制系统实训教学模式的探索%Practice Teaching Mode of Program-controlled X-ray Machine Control System

    Institute of Scientific and Technical Information of China (English)

    尹今扬; 芦静; 陈冰虹; 施珩

    2012-01-01

    Adopting practical teaching mode, the program-controlled X-ray machine control system was devided into five practical teaching module which enables students to learn program-controlled X-ray machine control system by linking theory with practice. After a series of training, the studenls can really combine theoretical knowledge with practice in learning program-controlled X-ray machine control system. The actual practice teaching proves that this teaching mode is of great help to students.%为采用实训教学模式,将程控X线机控制系统的学习设计成5个实训教学模块,使学生学习程控X线机控制系统时理论联系实际.经过系列模块实训,学生在学习程控X线机控制系统过程中,真正做到手脑并用,把理论知识和实际有机地结合起来.1年多的实训教学实践证明,该教学模式对学生的培养和锻炼有很大的帮助.

  15. Composite nanoparticle of Au and quantum dots for X-ray computed tomography and fluorescence dual-mode imaging in vivo

    Energy Technology Data Exchange (ETDEWEB)

    Song, Ji-Tao; Yang, Xiao-Quan; Zhang, Xiao-Shuai; Yan, Dong-Mei; Yao, Ming-Hao; Qin, Meng-Yao; Zhao, Yuan-Di, E-mail: zydi@mail.hust.edu.cn [Huazhong University of Science and Technology, Britton Chance Center for Biomedical Photonics at Wuhan National Laboratory for Optoelectronics - Hubei Bioinformatics & Molecular Imaging Key Laboratory, Department of Biomedical Engineering, College of Life Science and Technology (China)

    2015-12-15

    In this study, composite nanoparticles comprising Au nanoparticle and quantum dots were built and used for contrast-enhanced computed tomography imaging (CT) and fluorescence dual-mode imaging in vivo. The nanoparticle exhibited good monodispersity and good biocompatibility, and had excellent CT contrast-enhancement effect and fluorescence imaging capability. They were appropriate for being used as dual-mode imaging probe in vivo.

  16. Performance of the Tibet hybrid experiment (YAC-II + Tibet-III + MD) to measure the energy spectra of the light primary cosmic rays at energies 50-10,000 TeV

    Science.gov (United States)

    Huang, J.; Zhai, L. M.; Chen, D.; Shibata, M.; Katayose, Y.; Zhang, Ying; Liu, J. S.; Chen, Xu; Hu, X. B.; Zhang, X. Y.; Jia, H. Y.; Danzengluobu; Ohnishi, M.; Takita, M.

    2015-06-01

    A new hybrid detector system has been constructed by the Tibet ASγ collaboration at Tibet, China, since 2014 to measure the chemical composition of cosmic rays around the knee in the wide energy range. They consist of an air-shower-core detector-grid (YAC-II) to detect high energy electromagnetic component, the Tibet air-shower array (Tibet-III) and a large underground water-Cherenkov muon-detector array (MD). We have carried out a detailed air-shower Monte Carlo (MC) simulation to study the performance of the hybrid detectors by using CORSIKA (version 6.204), which includes QGSJET01c and SIBYLL2.1 hadronic interaction models. Assumed primary cosmic ray models are based on helium poor, helium rich and Gaisser's fit compositions around the knee. All detector responses are calculated using Geant4 (version 9.5) according to the real detector configurations and the MC events are reconstructed by the same procedure as the experimental data analysis. The energy determination is made by lateral density fitting (LDF) method using modified NKG function and the separation of the light components (proton, helium) is made by means of the artificial neural network (ANN) method and the random forest (RF) method. The systematic errors of the spectra of proton and helium caused by each steps of the analysis procedure are investigated including the dependence of the MC data on the hadronic interaction models and the primary composition models, and the algorithms for the primary mass identification. The systematic errors of the flux to be obtained by the new experiment are summarized as less than 30% in total. Our results show that the new hybrid experiment is powerful enough to study the chemical composition of the cosmic rays, in particular, to obtain the light-component spectra of the primary cosmic rays in 50-10,000 TeV energy range overlapping to the direct observation data at low energy side and ground-based indirect observations at high energy side. It is possible in this

  17. Choosing the appropriate configuration and cannulation strategies for extracorporeal membrane oxygenation: the potential dynamic process of organ support and importance of hybrid modes.

    Science.gov (United States)

    Sorokin, Vitaly; MacLaren, Graeme; Vidanapathirana, Puwalani C; Delnoij, Thijs; Lorusso, Roberto

    2017-05-01

    Extracorporeal membrane oxygenation (ECMO) is becoming a common procedure to support patients with severe cardio-circulatory or respiratory failure as well as in case of combined compromise of the two systems. Deciding which ECMO configuration and proceeding with an uneventful implantation, however, may present minor or major shortcomings. Cannulation techniques should be tailored to specific patient conditions to provide sufficient regional and systemic perfusion, both of which must be comprehensively monitored. Changes in the patient's status or suboptimal ECMO-related support, however, may occur and should trigger re-appraisal of the cannulation strategy and circuit configuration. This dynamic management, based around the adequacy of end organ perfusion and patient requirements, may dictate ECMO configuration and cannulation changes. In these circumstances, adjunct of a cannula in the venous or arterial vasculature may represent a mandatory procedure to solve unfavorable hemodynamic status or enhance ECMO efficiency. These type of ECMO configurations, different from basic one, and called hybrid configurations, may represent, therefore, a critical aspect of optimal ECMO management towards optimized and successful temporary support. The aim of this review is to critically appraise and summarize the existing literature on adult ECMO configuration including cannulation strategies and circuit arrangement, and highlighting more complex pattern required in some specific clinical settings. © 2017 The Authors. European Journal of Heart Failure © 2017 European Society of Cardiology.

  18. Double-Wall Carbon Nanotube Hybrid Mode-Locker in Tm-doped Fibre Laser: A Novel Mechanism for Robust Bound-State Solitons Generation

    Science.gov (United States)

    Chernysheva, Maria; Bednyakova, Anastasia; Al Araimi, Mohammed; Howe, Richard C. T.; Hu, Guohua; Hasan, Tawfique; Gambetta, Alessio; Galzerano, Gianluca; Rümmeli, Mark; Rozhin, Aleksey

    2017-03-01

    The complex nonlinear dynamics of mode-locked fibre lasers, including a broad variety of dissipative structures and self-organization effects, have drawn significant research interest. Around the 2 μm band, conventional saturable absorbers (SAs) possess small modulation depth and slow relaxation time and, therefore, are incapable of ensuring complex inter-pulse dynamics and bound-state soliton generation. We present observation of multi-soliton complex generation in mode-locked thulium (Tm)-doped fibre laser, using double-wall carbon nanotubes (DWNT-SA) and nonlinear polarisation evolution (NPE). The rigid structure of DWNTs ensures high modulation depth (64%), fast relaxation (1.25 ps) and high thermal damage threshold. This enables formation of 560-fs soliton pulses; two-soliton bound-state with 560 fs pulse duration and 1.37 ps separation; and singlet+doublet soliton structures with 1.8 ps duration and 6 ps separation. Numerical simulations based on the vectorial nonlinear Schr¨odinger equation demonstrate a transition from single-pulse to two-soliton bound-states generation. The results imply that DWNTs are an excellent SA for the formation of steady single- and multi-soliton structures around 2 μm region, which could not be supported by single-wall carbon nanotubes (SWNTs). The combination of the potential bandwidth resource around 2 μm with the soliton molecule concept for encoding two bits of data per clock period opens exciting opportunities for data-carrying capacity enhancement.

  19. Double-Wall Carbon Nanotube Hybrid Mode-Locker in Tm-doped Fibre Laser: A Novel Mechanism for Robust Bound-State Solitons Generation

    Science.gov (United States)

    Chernysheva, Maria; Bednyakova, Anastasia; Al Araimi, Mohammed; Howe, Richard C. T.; Hu, Guohua; Hasan, Tawfique; Gambetta, Alessio; Galzerano, Gianluca; Rümmeli, Mark; Rozhin, Aleksey

    2017-01-01

    The complex nonlinear dynamics of mode-locked fibre lasers, including a broad variety of dissipative structures and self-organization effects, have drawn significant research interest. Around the 2 μm band, conventional saturable absorbers (SAs) possess small modulation depth and slow relaxation time and, therefore, are incapable of ensuring complex inter-pulse dynamics and bound-state soliton generation. We present observation of multi-soliton complex generation in mode-locked thulium (Tm)-doped fibre laser, using double-wall carbon nanotubes (DWNT-SA) and nonlinear polarisation evolution (NPE). The rigid structure of DWNTs ensures high modulation depth (64%), fast relaxation (1.25 ps) and high thermal damage threshold. This enables formation of 560-fs soliton pulses; two-soliton bound-state with 560 fs pulse duration and 1.37 ps separation; and singlet+doublet soliton structures with 1.8 ps duration and 6 ps separation. Numerical simulations based on the vectorial nonlinear Schr¨odinger equation demonstrate a transition from single-pulse to two-soliton bound-states generation. The results imply that DWNTs are an excellent SA for the formation of steady single- and multi-soliton structures around 2 μm region, which could not be supported by single-wall carbon nanotubes (SWNTs). The combination of the potential bandwidth resource around 2 μm with the soliton molecule concept for encoding two bits of data per clock period opens exciting opportunities for data-carrying capacity enhancement. PMID:28287159

  20. Cystatins as calpain inhibitors: engineered chicken cystatin- and stefin B-kininogen domain 2 hybrids support a cystatin-like mode of interaction with the catalytic subunit of mu-calpain.

    Science.gov (United States)

    Díaz, B G; Gross, S; Assfalg-Machleidt, I; Pfeiler, D; Gollmitzer, N; Gabrijelcic-Geiger, D; Stubbs, M T; Fritz, H; Auerswald, E A; Machleidt, W

    2001-01-01

    Within the cystatin superfamily, only kininogen domain 2 (KD2) is able to inhibit mu- and m-calpain. In an attempt to elucidate the structural requirements of cystatins for calpain inhibition, we constructed recombinant hybrids of human stefin B (an intracellular family 1 cystatin) with KD2 and deltaL110 deletion mutants of chicken cystatin-KD2 hybrids. Substitution of the N-terminal contact region of stefin B by the corresponding KD2 sequence resulted in a calpain inhibitor of Ki = 188 nM. Deletion of L110, which forms a beta-bulge in family 1 and 2 cystatins but is lacking in KD2, improved inhibition of mu-calpain 4- to 8-fold. All engineered cystatins were temporary inhibitors of calpain due to slow substrate-like cleavage of a single peptide bond corresponding to Gly9-Ala10 in chicken cystatin. Biomolecular interaction analysis revealed that, unlike calpastatin, the cystatin-type inhibitors do not bind to the calmodulin-like domain of the small subunit of calpain, and their interaction with the mu-calpain heterodimer is completely prevented by a synthetic peptide comprising subdomain B of calpastatin domain 1. Based on these results we propose that (i) cystatin-type calpain inhibitors interact with the active site of the catalytic domain of calpain in a similar cystatin-like mode as with papain and (ii) the potential for calpain inhibition is due to specific subsites within the papain-binding regions of the general cystatin fold.

  1. Mode Gaussian beam tracing

    Science.gov (United States)

    Trofimov, M. Yu.; Zakharenko, A. D.; Kozitskiy, S. B.

    2016-10-01

    A mode parabolic equation in the ray centered coordinates for 3D underwater sound propagation is developed. The Gaussian beam tracing in this case is constructed. The test calculations are carried out for the ASA wedge benchmark and proved an excellent agreement with the source images method in the case of cross-slope propagation. But in the cases of wave propagation at some angles to the cross-slope direction an account of mode interaction becomes necessary.

  2. A Novel Organophosphorus Hybrid with Excellent Thermal Stability: Core-Shell Structure, Hybridization Mechanism, and Application in Flame Retarding Semi-Aromatic Polyamide.

    Science.gov (United States)

    Lin, Xue-Bao; Du, Shuang-Lan; Long, Jia-Wei; Chen, Li; Wang, Yu-Zhong

    2016-01-13

    An organophosphorous hybrid (BM@Al-PPi) with unique core-shell structure was prepared through hybridization reaction between boehmite (BM) as the inorganic substrate and phenylphosphinic acid (PPiA) as the organic modifier. Fourier transform infrared spectra (FTIR), solid state (31)P and (27)Al magic angle spinning nuclear magnetic resonance, X-ray diffraction, and element analysis were used to investigate the chemical structure of the hybrids, where the microrod-like core was confirmed as Al-PPi aggregates generated from the reaction between BM and PPiA, and those irregular nanoparticles in the shell belonged to residual BM. Compared with the traditional dissolution-precipitation process, a novel analogous suspension reaction mode was proposed to explain the hybridization process and the resulting product. Scanning electronic microscopy further proved the core-shell structure of the hybrids. BM exhibited much higher initial decomposition temperature than that of Al-PPi; therefore, the hybrid showed better thermal stability than Al-PPi, and it met the processing temperature of semi-aromatic polyamide (HTN, for instance) as an additive-type flame retardant. Limiting oxygen index and cone calorimetric analysis suggested the excellent flame-retardant performance and smoke suppressing activity by adding the resulting hybrid into HTN.

  3. Hybrid Baryons

    CERN Document Server

    Page, P R

    2003-01-01

    We review the status of hybrid baryons. The only known way to study hybrids rigorously is via excited adiabatic potentials. Hybrids can be modelled by both the bag and flux-tube models. The low-lying hybrid baryon is N 1/2^+ with a mass of 1.5-1.8 GeV. Hybrid baryons can be produced in the glue-rich processes of diffractive gamma N and pi N production, Psi decays and p pbar annihilation.

  4. On the Single-Photon-Counting (SPC) modes of imaging using an XFEL source

    Science.gov (United States)

    Wang, Zhehui

    2015-12-01

    The requirements to achieve high detection efficiency (above 50%) and gigahertz (GHz) frame rate for the proposed 42-keV X-ray free-electron laser (XFEL) at Los Alamos are summarized. Direct detection scenarios using C (diamond), Si, Ge and GaAs semiconductor sensors are analyzed. Single-photon counting (SPC) mode and weak SPC mode using Si can potentially meet the efficiency and frame rate requirements and be useful to both photoelectric absorption and Compton physics as the photon energy increases. Multilayer three-dimensional (3D) detector architecture, as a possible means to realize SPC modes, is compared with the widely used two-dimensional (2D) hybrid planar electrode structure and 3D deeply entrenched electrode architecture. Demonstration of thin film cameras less than 100-μm thick with onboard thin ASICs could be an initial step to realize multilayer 3D detectors and SPC modes for XFELs.

  5. On the Single-Photon-Counting (SPC) modes of imaging using an XFEL source

    CERN Document Server

    Wang, Zhehui

    2015-01-01

    The requirements to achieve high detection efficiency (above 50\\%) and gigahertz (GHz) frame rate for the proposed 42-keV X-ray free-electron laser (XFEL) at Los Alamos are summarized. Direct detection scenarios using C (diamond), Si, Ge and GaAs semiconductor sensors are analyzed. Single-photon counting (SPC) mode and weak SPC mode using Si can potentially meet the efficiency and frame rate requirements and be useful to both photoelectric absorption and Compton physics as the photon energy increases. Multilayer three-dimensional (3D) detector architecture, as a possible means to realize SPC modes, is compared with the widely used two-dimensional (2D) hybrid planar electrode structure and 3D deeply entrenched electrode architecture. Demonstration of thin film cameras less than 100-$\\mu$m thick with onboard thin ASICs could be an initial step to realize multilayer 3D detectors and SPC modes for XFELs.

  6. Hybrid position/force control of a constrained manipulator using adaptive wavelet sliding mode%受限机械臂的自适应小波滑模位置/力混合控制

    Institute of Scientific and Technical Information of China (English)

    周芳; 朱齐丹; 姜迈; 汪瞳

    2009-01-01

    针对终端运动受约束的机械臂位置/力混合控制问题,提出了一种自适应小波滑模控制算法.该控制方案将滑模控制的鲁棒性及自适应调整能力与小波神经网络相结合,根据坐标变换得到降阶位置/力模型,针对降阶模型采用小波神经网络在线学习系统未知动力学模型中的非线性部分,同时引入滑模控制自动调整小波网络权值参数,从而对神经网络的固有逼近误差进行有效补偿,达到期望的跟踪性能.二自由度机械臂的仿真结果表明该控制器能保证系统快速有效跟踪指定参考信号.%The hybrid position/force control of the robotic manipulator whose motion was constrained in the end was discussed. An adaptive wavelet sling mode control strategy was proposed, in which in-tegrating the robustness and self-adjustment advantages of sliding mode control were integrated into the wavelet network controller. A reduced position/force model was obtained according to the nonlinear translation, a wavelet network was used to learn the unknown nonlinear dynamic of system. Sim-ultaneous, the sliding mode technique was designed such that the wavelet weighted parameters could be automatically tuned thereby compensating the approximate error of the wavelet network in order to obtain the desired tracking performances. Simulation results of two-degree of freedom manipulator show the designed controller ensures the system track the desired reference signals quickly and efficiency.

  7. Overproduction, purification, crystallization and preliminary X-ray analysis of the peroxiredoxin domain of a larger natural hybrid protein from Thermotoga maritima

    Energy Technology Data Exchange (ETDEWEB)

    Barbey, Carole, E-mail: carole.barbey@smbh.univ-paris13.fr [Laboratoire de Biophysique Moléculaire, Cellulaire et Tissulaire, UMR 7033, Université Paris 13, UFR SMBH, 74 Rue Marcel Cachin, 93017 Bobigny CEDEX (France); Rouhier, Nicolas [Unité Mixte de Recherches 1136 INRA UHP (Interaction Arbres Microorganismes), IFR 110, Nancy Université BP 239, 54506 Vandoeuvre-lès-Nancy CEDEX (France); Haouz, Ahmed [Plate-forme de Cristallogenèse et Diffraction des Rayons X, Institut Pasteur, 25 Rue du Dr Roux, 75724 Paris (France); Navaza, Alda [Laboratoire de Biophysique Moléculaire, Cellulaire et Tissulaire, UMR 7033, Université Paris 13, UFR SMBH, 74 Rue Marcel Cachin, 93017 Bobigny CEDEX (France); Jacquot, Jean-Pierre [Unité Mixte de Recherches 1136 INRA UHP (Interaction Arbres Microorganismes), IFR 110, Nancy Université BP 239, 54506 Vandoeuvre-lès-Nancy CEDEX (France); Laboratoire de Biophysique Moléculaire, Cellulaire et Tissulaire, UMR 7033, Université Paris 13, UFR SMBH, 74 Rue Marcel Cachin, 93017 Bobigny CEDEX (France)

    2008-01-01

    Crystals of the peroxiredoxin domain of a larger natural hybrid protein from T. maritima were obtained which diffracted to 2.9 Å resolution on a synchrotron source. Thermotoga maritima contains a natural hybrid protein constituted of two moieties: a peroxiredoxin domain at the N-terminus and a nitroreductase domain at the C-terminus. The peroxiredoxin (Prx) domain has been overproduced and purified from Escherichia coli cells. The recombinant Prx domain, which is homologous to bacterial Prx BCP and plant Prx Q, folds properly into a stable protein that possesses biological activity. The recombinant protein was crystallized and synchrotron data were collected to 2.9 Å resolution. The crystals belonged to the tetragonal space group I422, with unit-cell parameters a = b = 176.67, c = 141.20 Å.

  8. Analysis of Hybrid Mode of Higher Education Quality Regulation in Germany%德国高等教育质量的混合管理模式分析

    Institute of Scientific and Technical Information of China (English)

    彭江

    2014-01-01

    20世纪60年代以来,德国高等教育系统逐渐构建起了自我管理、政府管理和市场管理相互融合与协作的混合式质量管理模式。这种“混合”既体现在高校、联邦与州政府、认证机构、专业机构、商业机构等管理主体之间的合作与协调,也体现在评估、认证、排名、审批、考试等管理工具的综合与平衡。政府管理在混合模式中发挥着主导、基础和保障作用。德国政府从高等教育的“审批政府”转变为“评估政府”与“认证政府”,是其主动选择的结果。%Since the 1960s,the higher education system of Germany has built up the hybrid model of quality regulation which integrated the self - regulation,government regulation and market regulation at the same time. Colleges and universities,federal and state government,accreditation agencies,specialized agencies and commer-cial organizations,which are the multi - principals of higher education quality regulation,cooperate and fuse each other. Assessment,accreditation,ranking,approval,examination,which are the multiform tools of higher educa-tion quality regulation,balance each other. Government plays a leading and fundamental role in the hybrid mode. To change from the“approving government”to“assessing government”and“accreditating government”,is the re-sult of government’s own choice.

  9. Hybrid Airy Plasmons with Dynamically Steerable Trajectories

    CERN Document Server

    Li, Rujiang; Lin, Xiao; Wang, Huaping; Xu, Zhiwei; Chen, Hongsheng

    2016-01-01

    With the intriguing properties of diffraction-free, self-accelerating, and self-healing, Airy plasmons are promising to be used in the trapping, transporting, and sorting of micro-objects, imaging, and chip scale signal processing. However, the high dissipative loss and the lack of dynamical steerability restrict the implementation of Airy plasmons in these applications. Here we reveal the hybrid Airy plasmons for the first time by taking a hybrid graphene-based plasmonic waveguide in the terahertz (THz) domain as an example. Due to the coupling between an optical mode and a plasmonic mode, the hybrid Airy plasmons can have large propagation lengths and effective transverse deflections, where the transverse waveguide confinements are governed by the hybrid modes with moderate quality factors. Meanwhile, the propagation trajectories of hybrid Airy plasmons are dynamically steerable by changing the chemical potential of graphene. These hybrid Airy plasmons may promote the further discovery of non-diffracting be...

  10. Hybrid Airy plasmons with dynamically steerable trajectories.

    Science.gov (United States)

    Li, Rujiang; Imran, Muhammad; Lin, Xiao; Wang, Huaping; Xu, Zhiwei; Chen, Hongsheng

    2017-01-26

    With their intriguing diffraction-free, self-accelerating, and self-healing properties, Airy plasmons show promise for use in the trapping, transporting, and sorting of micro-objects, imaging, and chip scale signal processing. However, high dissipative loss and lack of dynamical steerability restrict the implementation of Airy plasmons in these applications. Here we reveal hybrid Airy plasmons for the first time by taking a hybrid graphene-based plasmonic waveguide in the terahertz (THz) domain as an example. Due to coupling between optical modes and plasmonic modes, the hybrid Airy plasmons can have large propagation lengths and effective transverse deflections, where the transverse waveguide confinements are governed by the hybrid modes with moderate quality factors. Meanwhile, the propagation trajectories of the hybrid Airy plasmons are dynamically steerable by changing the chemical potential of graphene. These hybrid Airy plasmons may promote the further discovery of non-diffracting beams along with the emerging developments of optical tweezers and tractor beams.

  11. Extended X-ray absorption fine structure studies of Zn/sub 2/Fe/sub 2/ hybrid hemoglobins: absence of heme bond length changes in half-ligated species

    Energy Technology Data Exchange (ETDEWEB)

    Simolo, K.; Korszun, Z.R.; Stucky, G.; Moffat, K.; McLendon, G.

    1986-07-01

    Metal hybrid hemoglobins, in which Zn(II) replaces Fe(II), have been structurally characterized by extended X-ray absorption structure (EAFS) studies. Since Zn and Fe have very different K absorption edge energies, the structures of the ligated (Fe) and unligated (Zn) sites could be examined independently within a single molecule that mimics an intermediate ligation state. The observed EXAFS spectra and associated structural parameters are compared among the ligand free (..cap alpha..Zn)/sub 2/(..beta..Zn)/sub 2/, half-ligated (..cap alpha..FeCO)/sub 2/(..beta..Zn)/sub 2/ and (..cap alpha..Zn)/sub 2/(..beta..FeCO)/sub 2/, and fully ligated (..cap alpha..FeCO)/sub 2/(..beta..FeCO)/sub 2/ systems.

  12. La productivité semencière : l’enjeu du développement des hybrides Festulolium entre fétuque et ray-grass chez les graminées fourragères

    OpenAIRE

    Ghesquière, Marc; Bourgoin, Thierry; Hacquet, Jacques

    2016-01-01

    Les Festulolium sont des hybrides interspécifiques entre fétuque et ray-grass développés pour améliorer la production fourragère sous stress climatique, température et déficit hydrique. Il existe à ce jour 36 variétés inscrites au catalogue Européen dont 4 seulement au catalogue Français. Modifiée en 2004, la définition de Festulolium par l’Union Européenne peut recouvrir désormais une très grande diversité de formes ; 9 combinaisons amphiploïdes et plus de 60 formes introgressées à des degré...

  13. High-energy X-ray powder diffraction and atomic-pair distribution-function studies of charged/discharged structures in carbon-hybridized Li2MnSiO4 nanoparticles as a cathode material for lithiumion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Moriya, Maki; Miyahara, Masahiko; Hokazono, Mana; Sasaki, Hirokazu; Nemoto, Atsushi; Katayama, Shingo; Akimoto, Yuji; Hirano, Shin-ichi; Ren, Yang

    2014-10-01

    The stable cycling performance with a high discharge capacity of similar to 190 mAh g(-1) in a carbon-hybridized Li2MnSiO4 nanostructured powder has prompted an experimental investigation of the charged/discharged structures using synchrotron-based and laboratory-based X-rays and atomic-pair distributionfunction (PDF) analyses. A novel method of in-situ spray pyrolysis of a precursor solution with glucose as a carbon source enabled the successful synthesis of the carbon-hybridized Li2(M)nSiO(4) nanoparticles. The XRD patters of the discharged (lithiated) samples exhibit a long-range ordered structure characteristic of the (beta) Li2MnSiO4 crystalline phase (space group Pmn2(1)) which dissipates in the charged (delithiated) samples. However, upon discharging the long-range ordered structure recovers in each cycle. The disordered structure, according to the PDF analysis, is mainly due to local distortions of the MnO4 tetrahedra which show a mean Mn-O nearest neighbor distance shorter than that of the long-range ordered phase. These results corroborate the notion of the smaller Mn3+/Mn4+ ionic radii in the Li extracted phase versus the larger Mn2+ ionic radius in Li inserted phase. Thus Li extraction/insertion drives the fluctuation between the disordered and the long-range ordered structures. (C) 2014 Elsevier B.V. All rights reserved.

  14. Detective quantum efficiency for photon-counting hybrid pixel detectors in the tender X-ray domain: application to Medipix3RX.

    Science.gov (United States)

    Rinkel, Jean; Magalhães, Debora; Wagner, Franz; Meneau, Florian; Cesar Vicentin, Flavio

    2016-01-01

    Synchrotron-radiation-based X-ray imaging techniques using tender X-rays are facing a growing demand, in particular to probe the K absorption edges of low-Z elements. Here, a mathematical model has been developed for estimating the detective quantum efficiency (DQE) at zero spatial frequency in the tender X-ray energy range for photon-counting detectors by taking into account the influence of electronic noise. The experiments were carried out with a Medipix3RX ASIC bump-bonded to a 300 µm silicon sensor at the Soft X-ray Spectroscopy beamline (D04A-SXS) of the Brazilian Synchrotron Light Laboratory (LNLS, Campinas, Brazil). The results show that Medipix3RX can be used to develop new imaging modalities in the tender X-ray range for energies down to 2 keV. The efficiency and optimal DQE depend on the energy and flux of the photons. The optimal DQE values were found in the 7.9-8.6 keV photon energy range. The DQE deterioration for higher energies due to the lower absorption efficiency of the sensor and for lower energies due to the electronic noise has been quantified. The DQE for 3 keV photons and 1 × 10(4) photons pixel(-1) s(-1) is similar to that obtained with 19 keV photons. Based on our model, the use of Medipix3RX could be extended down to 2 keV which is crucial for coming applications in imaging techniques at modern synchrotron sources.

  15. The Energy Spectrum of Ultra-High-Energy Cosmic Rays Measured by the Telescope Array FADC Fluorescence Detectors in Monocular Mode

    CERN Document Server

    Abu-Zayyad, T; Allen, M; Anderson, R; Azuma, R; Barcikowski, E; Belz, J W; Bergman, D R; Blake, S A; Cady, R; Cheon, B G; Chiba, J; Chikawa, M; Cho, E J; Cho, W R; Fujii, H; Fujii, T; Fukuda, T; Fukushima, M; Hanlon, W; Hayashi, K; Hayashi, Y; Hayashida, N; Hibino, K; Hiyama, K; Honda, K; Iguchi, T; Ikeda, D; Ikuta, K; Inoue, N; Ishii, T; Ishimori, R; Ito, H; Ivanov, D; Iwamoto, S; Jui, C C H; Kadota, K; Kakimoto, F; Kalashev, O; Kanbe, T; Kasahara, K; Kawai, H; Kawakami, S; Kawana, S; Kido, E; Kim, H B; Kim, H K; Kim, J H; Kitamoto, K; Kitamura, S; Kitamura, Y; Kobayashi, K; Kobayashi, Y; Kondo, Y; Kuramoto, K; Kuzmin, V; Kwon, Y J; Lan, J; Lim, S I; Lundquist, J P; Machida, S; Martens, K; Matsuda, T; Matsuura, T; Matsuyama, T; Matthews, J N; Myers, I; Minamino, M; Miyata, K; Murano, Y; Nagataki, S; Nakamura, T; Nam, S W; Nonaka, T; Ogio, S; Ogura, J; Ohnishi, M; Ohoka, H; Oki, K; Oku, D; Okuda, T; Ono, M; Oshima, A; Ozawa, S; Park, I H; Pshirkov, M S; Rodriguez, D C; Roh, S Y; Rubtsov, G; Ryu, D; Sagawa, H; Sakurai, N; Sampson, A L; Scott, L M; Shah, P D; Shibata, F; Shibata, T; Shimodaira, H; Shin, B K; Shin, J I; Shirahama, T; Smith, J D; Sokolsky, P; Sonley, T J; Springer, R W; Stokes, B T; Stratton, S R; Stroman, T A; Suzuki, S; Takahashi, Y; Takeda, M; Taketa, A; Takita, M; Tameda, Y; Tanaka, H; Tanaka, K; Tanaka, M; Thomas, S B; Thomson, G B; Tinyakov, P; Tkachev, I; Tokuno, H; Tomida, T; Troitsky, S; Tsunesada, Y; Tsutsumi, K; Tsuyuguchi, Y; Uchihori, Y; Udo, S; Ukai, H; Vasiloff, G; Wada, Y; Wong, T; Yamakawa, Y; Yamane, R; Yamaoka, H; Yamazaki, K; Yang, J; Yoneda, Y; Yoshida, S; Yoshii, H; Zollinger, R; Zundel, Z

    2013-01-01

    We present a measurement of the energy spectrum of ultra-high-energy cosmic rays performed by the Telescope Array experiment using monocular observations from its two new FADC-based fluorescence detectors. After a short description of the experiment, we describe the data analysis and event reconstruction procedures. Since the aperture of the experiment must be calculated by Monte Carlo simulation, we describe this calculation and the comparisons of simulated and real data used to verify the validity of the aperture calculation. Finally, we present the energy spectrum calculated from the merged monocular data sets of the two FADC-based detectors, and also the combination of this merged spectrum with an independent, previously published monocular spectrum measurement performed by Telescope Array's third fluorescence detector (Abu-Zayyad {\\it et al.}, {Astropart. Phys.} 39 (2012), 109). This combined spectrum corroborates the recently published Telescope Array surface detector spectrum (Abu-Zayyad {\\it et al.}, ...

  16. Depth of interaction and bias voltage depenence of the spectral response in a pixellated CdTe detector operating in time-over-threshold mode subjected to monochromatic X-rays

    Science.gov (United States)

    Fröjdh, E.; Fröjdh, C.; Gimenez, E. N.; Maneuski, D.; Marchal, J.; Norlin, B.; O'Shea, V.; Stewart, G.; Wilhelm, H.; Modh Zain, R.; Thungström, G.

    2012-03-01

    High stopping power is one of the most important figures of merit for X-ray detectors. CdTe is a promising material but suffers from: material defects, non-ideal charge transport and long range X-ray fluorescence. Those factors reduce the image quality and deteriorate spectral information. In this project we used a monochromatic pencil beam collimated through a 20μm pinhole to measure the detector spectral response in dependance on the depth of interaction. The sensor was a 1mm thick CdTe detector with a pixel pitch of 110μm, bump bonded to a Timepix readout chip operating in Time-Over-Threshold mode. The measurements were carried out at the Extreme Conditions beamline I15 of the Diamond Light Source. The beam was entering the sensor at an angle of \\texttildelow20 degrees to the surface and then passed through \\texttildelow25 pixels before leaving through the bottom of the sensor. The photon energy was tuned to 77keV giving a variation in the beam intensity of about three orders of magnitude along the beam path. Spectra in Time-over-Threshold (ToT) mode were recorded showing each individual interaction. The bias voltage was varied between -30V and -300V to investigate how the electric field affected the spectral information. For this setup it is worth noticing the large impact of fluorescence. At -300V the photo peak and escape peak are of similar height. For high bias voltages the spectra remains clear throughout the whole depth but for lower voltages as -50V, only the bottom part of the sensor carries spectral information. This is an effect of the low hole mobility and the longer range the electrons have to travel in a low field.

  17. Acoustic instability driven by cosmic-ray streaming

    Science.gov (United States)

    Begelman, Mitchell C.; Zweibel, Ellen G.

    1994-01-01

    We study the linear stability of compressional waves in a medium through which cosmic rays stream at the Alfven speed due to strong coupling with Alfven waves. Acoustic waves can be driven unstable by the cosmic-ray drift, provided that the streaming speed is sufficiently large compared to the thermal sound speed. Two effects can cause instability: (1) the heating of the thermal gas due to the damping of Alfven waves driven unstable by cosmic-ray streaming; and (2) phase shifts in the cosmic-ray pressure perturbation caused by the combination of cosmic-ray streaming and diffusion. The instability does not depend on the magnitude of the background cosmic-ray pressure gradient, and occurs whether or not cosmic-ray diffusion is important relative to streaming. When the cosmic-ray pressure is small compared to the gas pressure, or cosmic-ray diffusion is strong, the instability manifests itself as a weak overstability of slow magnetosonic waves. Larger cosmic-ray pressure gives rise to new hybrid modes, which can be strongly unstable in the limits of both weak and strong cosmic-ray diffusion and in the presence of thermal conduction. Parts of our analysis parallel earlier work by McKenzie & Webb (which were brought to our attention after this paper was accepted for publication), but our treatment of diffusive effects, thermal conduction, and nonlinearities represent significant extensions. Although the linear growth rate of instability is independent of the background cosmic-ray pressure gradient, the onset of nonlinear eff ects does depend on absolute value of DEL (vector differential operator) P(sub c). At the onset of nonlinearity the fractional amplitude of cosmic-ray pressure perturbations is delta P(sub C)/P(sub C) approximately (kL) (exp -1) much less than 1, where k is the wavenumber and L is the pressure scale height of the unperturbed cosmic rays. We speculate that the instability may lead to a mode of cosmic-ray transport in which plateaus of uniform cosmic-ray

  18. Evaluation of a real-time hybrid three-dimensional echo and X-ray imaging system for guidance of cardiac catheterisation procedures.

    Science.gov (United States)

    Housden, R J; Arujuna, A; Ma, Y; Nijhof, N; Gijsbers, G; Bullens, R; O'Neill, M; Cooklin, M; Rinaldi, C A; Gill, J; Kapetanakis, S; Hancock, J; Thomas, M; Razavi, R; Rhode, K S

    2012-01-01

    Minimally invasive cardiac surgery is made possible by image guidance technology. X-ray fluoroscopy provides high contrast images of catheters and devices, whereas 3D ultrasound is better for visualising cardiac anatomy. We present a system in which the two modalities are combined, with a trans-esophageal echo volume registered to and overlaid on an X-ray projection image in real-time. We evaluate the accuracy of the system in terms of both temporal synchronisation errors and overlay registration errors. The temporal synchronisation error was found to be 10% of the typical cardiac cycle length. In 11 clinical data sets, we found an average alignment error of 2.9 mm. We conclude that the accuracy result is very encouraging and sufficient for guiding many types of cardiac interventions. The combined information is clinically useful for placing the echo image in a familiar coordinate system and for more easily identifying catheters in the echo volume.

  19. Hybrid vehicles

    Energy Technology Data Exchange (ETDEWEB)

    West, J.G.W. [Electrical Machines (United Kingdom)

    1997-07-01

    The reasons for adopting hybrid vehicles result mainly from the lack of adequate range from electric vehicles at an acceptable cost. Hybrids can offer significant improvements in emissions and fuel economy. Series and parallel hybrids are compared. A combination of series and parallel operation would be the ideal. This can be obtained using a planetary gearbox as a power split device allowing a small generator to transfer power to the propulsion motor giving the effect of a CVT. It allows the engine to run at semi-constant speed giving better fuel economy and reduced emissions. Hybrid car developments are described that show the wide range of possible hybrid systems. (author)

  20. Conditional Hybrid Nonclassicality

    Science.gov (United States)

    Agudelo, E.; Sperling, J.; Costanzo, L. S.; Bellini, M.; Zavatta, A.; Vogel, W.

    2017-09-01

    We derive and implement a general method to characterize the nonclassicality in compound discrete- and continuous-variable systems. For this purpose, we introduce the operational notion of conditional hybrid nonclassicality which relates to the ability to produce a nonclassical continuous-variable state by projecting onto a general superposition of discrete-variable subsystem. We discuss the importance of this form of quantumness in connection with interfaces for quantum communication. To verify the conditional hybrid nonclassicality, a matrix version of a nonclassicality quasiprobability is derived and its sampling approach is formulated. We experimentally generate an entangled, hybrid Schrödinger cat state, using a coherent photon-addition process acting on two temporal modes, and we directly sample its nonclassicality quasiprobability matrix. The introduced conditional quantum effects are certified with high statistical significance.

  1. Response of a hybrid pixel detector (MEDIPIX3) to different radiation sources for medical applications

    Energy Technology Data Exchange (ETDEWEB)

    Chumacero, E. Miguel; De Celis Alonso, B.; Martínez Hernández, M. I.; Vargas, G.; Moreno Barbosa, E., E-mail: emoreno.emb@gmail.com [Facultad de Ciencias Físico Matemáticas, Benemérita Universidad Autónoma de Puebla, Av. San Claudio y Rio Verde, Puebla (Mexico); Moreno Barbosa, F. [Hospital General del Sur Hospital de la Mujer, Puebla (Mexico)

    2014-11-07

    The development in semiconductor CMOS technology has enabled the creation of sensitive detectors for a wide range of ionizing radiation. These devices are suitable for photon counting and can be used in imaging and tomography X-ray diagnostics. The Medipix[1] radiation detection system is a hybrid silicon pixel chip developed for particle tracking applications in High Energy Physics. Its exceptional features (high spatial and energy resolution, embedded ultra fast readout, different operation modes, etc.) make the Medipix an attractive device for applications in medical imaging. In this work the energy characterization of a third-generation Medipix chip (Medipix3) coupled to a silicon sensor is presented. We used different radiation sources (strontium 90, iron 55 and americium 241) to obtain the response curve of the hybrid detector as a function of energy. We also studied the contrast of the Medipix as a measure of pixel noise. Finally we studied the response to fluorescence X rays from different target materials (In, Pd and Cd) for the two data acquisition modes of the chip; single pixel mode and charge summing mode.

  2. High-contrast X-ray micro-tomography of low attenuation samples using large area hybrid semiconductor pixel detector array of 10 × 5 Timepix chips

    Science.gov (United States)

    Karch, J.; Krejci, F.; Bartl, B.; Dudak, J.; Kuba, J.; Kvacek, J.; Zemlicka, J.

    2016-01-01

    State-of-the-art hybrid pixel semiconductor detectors provide excellent imaging properties such as unlimited dynamic range, high spatial resolution, high frame rate and energy sensitivity. Nevertheless, a limitation in the use of these devices for imaging has been the small sensitive area of a few square centimetres. In the field of microtomography we make use of a large area pixel detector assembled from 50 Timepix edgeless chips providing fully sensitive area of 14.3 × 7.15 cm2. We have successfully demonstrated that the enlargement of the sensitive area enables high-quality tomographic measurements of whole objects with high geometrical magnification without any significant degradation in resulting reconstructions related to the chip tilling and edgeless sensor technology properties. The technique of micro-tomography with the newly developed large area detector is applied for samples formed by low attenuation, low contrast materials such a seed from Phacelia tanacetifolia, a charcoalified wood sample and a beeswax seal sample.

  3. Porosity in hybrid materials

    Energy Technology Data Exchange (ETDEWEB)

    Schaefer, D.W.; Beaucage, G.; Loy, D. [Sandia National Labs., Albuquerque, NM (United States)

    1995-12-31

    Multicomponent, or hybrid composites are emerging as precursors to porous materials. Sacrifice of an ephemeral phase can be used to generate porosity, the nature of which depends on precursor structure. Retention of an organic constituent, on the other hand, can add desirable toughness to an otherwise brittle ceramic. We use small-angle x-ray and neutron scattering to examine porosity in both simple and hybrid materials. We find that microphase separation controls porosity in almost all systems studied. Pore distributions are controlled by the detailed bonding within and between phases as well as the flexibility of polymeric constituents. Thus hybridization opens new regions of pore distributions not available in simple systems. We look at several sacrificial concepts and show that it is possible to generate multimodal pore size distributions due to the complicated phase structure in the precursor.

  4. Analysis of hybrid viscous damper by real time hybrid simulations

    DEFF Research Database (Denmark)

    Brodersen, Mark Laier; Ou, Ge; Høgsberg, Jan Becker

    2016-01-01

    Results from real time hybrid simulations are compared to full numerical simulations for a hybrid viscous damper, composed of a viscous dashpot in series with an active actuator and a load cell. By controlling the actuator displacement via filtered integral force feedback the damping performance...... of the hybrid viscous damper is improved, while for pure integral force feedback the damper stroke is instead increased. In the real time hybrid simulations viscous damping is emulated by a bang-bang controlled Magneto-Rheological (MR) damper. The controller activates high-frequency modes and generates drift...... in the actuator displacement, and only a fraction of the measured damper force can therefore be used as input to the investigated integral force feedback in the real time hybrid simulations....

  5. 500 fs Streak Camera for UV-Hard X-Rays in 1 kHz Accumulating Mode with Optical 'Jitter Free' Synchronisation

    CERN Document Server

    Scheidt, K

    2000-01-01

    The development at the ESRF of a jitter-free, laser triggered Streak Camera has now yielded time resolution results as short as 460 fs while operating in accumulating mode. The so-called jitter-free synchronisation between the laser light and the Streak Camera is performed through a GaAs photo-switch in a simple HV circuit that connects directly to the Streak tube's deflection plates. The novelty of this technique permits to obtain excellent dynamic range measurements in a shot-to-shot accumulation of ultra fast (laser stimulated) events at up to 1kHz without degrading the time resolution. Important insight was obtained on the quality of this optical synchronisation and its dependence on the laser characteristics, the switch circuit, and the structure of the GaAs switch itself. This permitted to suppress the jitter causes and today the 500 fs limitation is imposed by the streak tube's intrinsic time resolution. This work was done by measuring (with Au or Pd photo-cathodes) the 3rd harmonic (i.e. 267 nm) of a ...

  6. Interlaboratory variation in scoring dicentric chromosomes in a case of partial-body x-ray exposure: implications for biodosimetry networking and cytogenetic "triage mode" scoring.

    Science.gov (United States)

    Ainsbury, E A; Livingston, G K; Abbott, M G; Moquet, J E; Hone, P A; Jenkins, M S; Christensen, D M; Lloyd, D C; Rothkamm, K

    2009-12-01

    The international radiation biodosimetry community has recently been engaged in activities focused on establishing cooperative networks for biodosimetric triage for radiation emergency scenarios involving mass casualties. To this end, there have been several recent publications in the literature regarding the potential for shared scoring in such an accident or incident. We present details from a medical irradiation case where two independently validated laboratories found very different yields of dicentric chromosome aberrations. The potential reasons for this disparity are discussed, and the actual reason is identified as being the partial-body nature of the radiation exposure combined with differing criteria for metaphase selection. In the context of the recent networking activity, this report is intended to highlight the fact that shared scoring may produce inconsistencies and that further validation of the scoring protocols and experimental techniques may be required before the networks are prepared to deal satisfactorily with a radiological or nuclear emergency. Also, the findings presented here clearly demonstrate the limitations of the dicentric assay for estimating radiation doses after partial-body exposures and bring into question the usefulness of rapid "triage mode" scoring in such exposure scenarios.

  7. Exploration on the Lean Production Mode of X-ray Medical Equipment%X射线医疗设备精益生产方式探究

    Institute of Scientific and Technical Information of China (English)

    王一开

    2015-01-01

    本文通过对X射线生产线工业制程的探索研究,从精益生产的角度改良流程和工作方式,最终达到提高工作效率和减少不必要的浪费的目的,得出在高端医疗设备领域的精益生产方法和措施,并同时提供理论依据。在分析和推断的同时,提出导入精益生产方式时需要注意的问题。%This article studies the industrial process of X-ray production line, improves the process and working way from the angle of lean production to improve work efficiency and reduce unnecessary waste. The lean production methods and measures in the field of high-end medical equipment are concluded, and theoretical basis is provided. In analysis and inference, matters needing attention are put forward.

  8. Iron, copper, zinc and bromine mapping in cirrhotic liver slices from patients with hemochromatosis studied by microscopic synchrotron radiation X-ray fluorescence analysis in continuous scanning mode

    Energy Technology Data Exchange (ETDEWEB)

    Osterode, W. [Medizinische Universitaet Wien, Univ. Klinik fuer Innere Medizin IV, Klinische Abteilung fuer Arbeitsmedizin, Waehringer Guertel 18-20, A-1090 Wien (Austria)], E-mail: wolf.osterode@meduniwien.ac.at; Falkenberg, G. [Hamburger Synchrotronstrahlungslabor HASYLAB, Deutsches Elektronen-Synchrotron DESY (Germany); Hoeftberger, R. [Medizinische Universitaet Wien, Klinisches Institut fuer Neurologie (Austria); Wrba, F. [Medizinische Universitaet Wien, Klinisches Institut fuer Klinische Pathologie (Austria)

    2007-07-15

    Iron (Fe) and copper (Cu) are essential metals in physiological cell metabolism. While Fe is easy to determine biochemically in histological slices, Cu and zinc (Zn) distribution is frequently critical in confirming the presence of an overload in disturbed Fe/Cu metabolism. To analyze Fe, Cu and Zn in a near histological resolution, energy dispersive microscopic synchrotron radiation X-ray fluorescence was applied. In normal liver tissue, after fixation and imbedding in paraffin, mean Fe, Cu and Zn concentrations were 152 {+-} 54, 20.1 {+-} 4.3 and 88.919.5 {mu}g/g sample weight, respectively. No substantial, characteristic differences in their distribution were found in the two-dimensional scans. In slices from patients with hemochromatosis mean Fe, Cu and Zn concentrations were 1102 {+-} 539, 35.9 {+-} 14.6 and 27.2 {+-} 6.7 {mu}g/g sample weight, respectively. Additionally, a significant decrease in phosphorus and sulphur concentrations existed. An increased Cu around cirrhotic regenerations nodules is mostly associated with a lymphocytic infiltration in this region. Analyzing concentrations of Fe in different regions of the samples show a clear negative dependency between Fe and Cu, Cu and Zn, but a positive one between Fe and Zn. Conclusion: With a focal beam size of 15 {mu}m in diameter a resolution of the elemental distribution was achieved which is widely comparable with stained histological slices (20x light microscope). The analysis of simultaneous determined elements reveals metabolic differences between Fe, Cu and Zn in liver tissue from patients with hemochromatosis.

  9. Iron, copper, zinc and bromine mapping in cirrhotic liver slices from patients with hemochromatosis studied by microscopic synchrotron radiation X-ray fluorescence analysis in continuous scanning mode

    Science.gov (United States)

    Osterode, W.; Falkenberg, G.; Höftberger, R.; Wrba, F.

    2007-07-01

    Iron (Fe) and copper (Cu) are essential metals in physiological cell metabolism. While Fe is easy to determine biochemically in histological slices, Cu and zinc (Zn) distribution is frequently critical in confirming the presence of an overload in disturbed Fe/Cu metabolism. To analyze Fe, Cu and Zn in a near histological resolution, energy dispersive microscopic synchrotron radiation X-ray fluorescence was applied. In normal liver tissue, after fixation and imbedding in paraffin, mean Fe, Cu and Zn concentrations were 152 ± 54, 20.1 ± 4.3 and 88.919.5 μg/g sample weight, respectively. No substantial, characteristic differences in their distribution were found in the two-dimensional scans. In slices from patients with hemochromatosis mean Fe, Cu and Zn concentrations were 1102 ± 539, 35.9 ± 14.6 and 27.2 ± 6.7 μg/g sample weight, respectively. Additionally, a significant decrease in phosphorus and sulphur concentrations existed. An increased Cu around cirrhotic regenerations nodules is mostly associated with a lymphocytic infiltration in this region. Analyzing concentrations of Fe in different regions of the samples show a clear negative dependency between Fe and Cu, Cu and Zn, but a positive one between Fe and Zn. Conclusion: With a focal beam size of 15 μm in diameter a resolution of the elemental distribution was achieved which is widely comparable with stained histological slices (20× light microscope). The analysis of simultaneous determined elements reveals metabolic differences between Fe, Cu and Zn in liver tissue from patients with hemochromatosis.

  10. X-ray structure of Candida antarctica lipase A shows a novel lid structure and a likely mode of interfacial activation.

    Science.gov (United States)

    Ericsson, Daniel J; Kasrayan, Alex; Johansson, Patrik; Bergfors, Terese; Sandström, Anders G; Bäckvall, Jan-E; Mowbray, Sherry L

    2008-02-08

    In nature, lipases (EC 3.1.1.3) catalyze the hydrolysis of triglycerides to form glycerol and fatty acids. Under the appropriate conditions, the reaction is reversible, and so biotechnological applications commonly make use of their capacity for esterification as well as for hydrolysis of a wide variety of compounds. In the present paper, we report the X-ray structure of lipase A from Candida antarctica, solved by single isomorphous replacement with anomalous scattering, and refined to 2.2-A resolution. The structure is the first from a novel family of lipases. Contrary to previous predictions, the fold includes a well-defined lid as well as a classic alpha/beta hydrolase domain. The catalytic triad is identified as Ser184, Asp334 and His366, which follow the sequential order considered to be characteristic of lipases; the serine lies within a typical nucleophilic elbow. Computer docking studies, as well as comparisons to related structures, place the carboxylate group of a fatty acid product near the serine nucleophile, with the long lipid tail closely following the path through the lid that is marked by a fortuitously bound molecule of polyethylene glycol. For an ester substrate to bind in an equivalent fashion, loop movements near Phe431 will be required, suggesting the primary focus of the conformational changes required for interfacial activation. Such movements will provide virtually unlimited access to solvent for the alcohol moiety of an ester substrate. The structure thus provides a basis for understanding the enzyme's preference for acyl moieties with long, straight tails, and for its highly promiscuous acceptance of widely different alcohol and amine moieties. An unconventional oxyanion hole is observed in the present structure, although the situation may change during interfacial activation.

  11. Hybrid Models in Loop Quantum Cosmology

    CERN Document Server

    Navascués, B Elizaga; Marugán, G A Mena

    2016-01-01

    In the framework of Loop Quantum Cosmology, inhomogeneous models are usually quantized by means of a hybrid approach that combines loop quantization techniques with standard quantum field theory methods. This approach is based on a splitting of the phase space in a homogeneous sector, formed by global, zero-modes, and an inhomogeneous sector, formed by the remaining, infinite number of modes, that describe the local degrees of freedom. Then, the hybrid quantization is attained by adopting a loop representation for the homogeneous gravitational sector, while a Fock representation is used for the inhomogeneities. The zero-mode of the Hamiltonian constraint operator couples the homogeneous and inhomogeneous sectors. The hybrid approach, therefore, is expected to provide a suitable quantum theory in regimes where the main quantum effects of the geometry are those affecting the zero-modes, while the inhomogeneities, still being quantum, can be treated in a more conventional way. This hybrid strategy was first prop...

  12. Optical and Ionization Basic Cosmic Ray Detector

    Science.gov (United States)

    Felix, Julian; Andrade, Diego A.; Araujo, Aurora C.; Arceo, Luis; Cervantes, Carlos A.; Molina, Jorge A.; Palacios, Luz R.

    2014-03-01

    There are drift tubes, operating in the Geiger mode, to detect ionization radiation and there are Cerenkov radiation detectors based on photomultiplier tubes. Here is the design, the construction, the operation and the characterization of a hybrid detector that combines both a drift tube and a Cerenkov detector, used mainly so far to detect cosmic rays. The basic cell is a structural Aluminum 101.6 cm-long, 2.54 cm X 2.54 cm-cross section, 0.1 cm-thick tube, interiorly polished to mirror and slightly covered with TiCO2, and filed with air, and Methane-Ar at different concentrations. There is a coaxial 1 mil Tungsten wire Au-coated at +700 to +1200 Volts electronically instrumented to read out in both ends; and there is in each end of the Aluminum tube a S10362-11-100U Hamamatsu avalanche photodiode electronically instrumented to be read out simultaneously with the Tungsten wire signal. This report is about the technical operation and construction details, the characterization results and potential applications of this hybrid device as a cosmic ray detector element. CONACYT, Mexico.

  13. Synthesis and first X-ray structure of a hexa-peri-hexabenzocoronene-fullerene-dyad: a model for an inter-carbon-allotrope hybrid.

    Science.gov (United States)

    Kratzer, Andreas; Englert, Jan M; Lungerich, Dominik; Heinemann, Frank W; Jux, Norbert; Hirsch, Andreas

    2014-01-01

    The synthesis of a new hexa-peri-hexabenzocoronene (HBC)-fullerene dyad was accomplished involving a covalent linkage between both the planar and the spherical conjugated π-system of the two chromophores. We also present the first X-ray single crystal structure of a HBC-fullerene conjugate. A very short HBC-fullerene distance of 3.2 Å is observed. For the synthesis of this molecule, a new versatile applicable template, namely, a mono-functionalized hexa-peri-hexabenzocoronene was attached to a fullerene. Absorption and fluorescence spectroscopy, as well as quantum yield measurements of , indicated close electronic communication between the two subunits, which is promising for possible applications in molecular electronics.

  14. First detective quantum efficiency measurement of 500 {mu}m silicon hybrid pixel sensor with photon counting readout for X-ray medical imaging

    Energy Technology Data Exchange (ETDEWEB)

    Surre, Benjamin [Laboratoire de Biophysique medicale, University of Auvergne, Clermont-Ferrand (France)]. E-mail: Benjamin.surre@u-clermontl.fr; Caria, Mario [Laboratoire de Biophysique medicale, University of Auvergne, Clermont-Ferrand (France); Chaput, Julien [Laboratoire de Biophysique medicale, University of Auvergne, Clermont-Ferrand (France); Hassoun, Thierry [Laboratoire de Biophysique medicale, University of Auvergne, Clermont-Ferrand (France); Laverroux, Fabien [Laboratoire de Biophysique medicale, University of Auvergne, Clermont-Ferrand (France); Sarry, Laurent [Equipe de Recherche en Signal et Imagerie Medicale, EA3295, Clermont-Ferrand (France)

    2005-07-01

    We report the performances of a 500 {mu}m pixellated silicon sensor bonded to the photon counting chip Medipix2 [1]. In order to perform an absolute characterization of our detector, we measured both the pre-sampling MTF and NPS with respect to the International standard IEC-62220-1. From those data we have been able to extract the Detective Quantum Efficiency (DQE) and hence to assess the suitability of our detector for X-ray medical imaging purpose. Due to poor absorption of the Si at 70 kV the DQE peaked at 0.06 for null frequency. Nevertheless, these results are very promising since thicker Si or more absorbing material such as GaAs will soon be available.

  15. Detecting liquid threats with x-ray diffraction imaging (XDi) using a hybrid approach to navigate trade-offs between photon count statistics and spatial resolution

    Science.gov (United States)

    Skatter, Sondre; Fritsch, Sebastian; Schlomka, Jens-Peter

    2016-05-01

    The performance limits were explored for an X-ray Diffraction based explosives detection system for baggage scanning. This XDi system offers 4D imaging that comprises three spatial dimensions with voxel sizes in the order of ~(0.5cm)3, and one spectral dimension for material discrimination. Because only a very small number of photons are observed for an individual voxel, material discrimination cannot work reliably at the voxel level. Therefore, an initial 3D reconstruction is performed, which allows the identification of objects of interest. Combining all the measured photons that scattered within an object, more reliable spectra are determined on the object-level. As a case study we looked at two liquid materials, one threat and one innocuous, with very similar spectral characteristics, but with 15% difference in electron density. Simulations showed that Poisson statistics alone reduce the material discrimination performance to undesirable levels when the photon counts drop to 250. When additional, uncontrolled variation sources are considered, the photon count plays a less dominant role in detection performance, but limits the performance also for photon counts of 500 and higher. Experimental data confirmed the presence of such non-Poisson variation sources also in the XDi prototype system, which suggests that the present system can still be improved without necessarily increasing the photon flux, but by better controlling and accounting for these variation sources. When the classification algorithm was allowed to use spectral differences in the experimental data, the discrimination between the two materials improved significantly, proving the potential of X-ray diffraction also for liquid materials.

  16. Implementation of ultrafast X-ray diffraction at the 1W2B wiggler beamline of Beijing Synchrotron Radiation Facility.

    Science.gov (United States)

    Sun, Da Rui; Xu, Guang Lei; Zhang, Bing Bing; Du, Xue Yan; Wang, Hao; Li, Qiu Ju; Zhou, Yang Fan; Li, Zhen Jie; Zhang, Yan; He, Jun; Yue, Jun Hui; Lei, Ge; Tao, Ye

    2016-05-01

    The implementation of a laser pump/X-ray probe scheme for performing picosecond-resolution X-ray diffraction at the 1W2B wiggler beamline at Beijing Synchrotron Radiation Facility is reported. With the hybrid fill pattern in top-up mode, a pixel array X-ray detector was optimized to gate out the signal from the singlet bunch with interval 85 ns from the bunch train. The singlet pulse intensity is ∼2.5 × 10(6) photons pulse(-1) at 10 keV. The laser pulse is synchronized to this singlet bunch at a 1 kHz repetition rate. A polycapillary X-ray lens was used for secondary focusing to obtain a 72 µm (FWHM) X-ray spot. Transient photo-induced strain in BiFeO3 film was observed at a ∼150 ps time resolution for demonstration.

  17. Hybrid Composite of Polyaniline Containing Carbon Nanotube

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Carbon nanotube-polyaniline hybrid material was synthesized by emulsion polymerization in-situ. The morphology of hybrid material was studied by TEM and X-ray diffraction. The conductivity of nanocomposite increases with the increasing of carbon nanotube content because of the new conductivity passageways formed by carbon nanotubes.

  18. Synthesis, X-ray crystal structure and highly non-linear optical properties of inorganic-organic hybrid compound: 1,4-Diazbicyclo-octane oxonium tri- nitrates single crystal

    Science.gov (United States)

    Henchiri, Rokaya; Ennaceur, Nasreddine; Cordier, Marie; Ledoux-Rak, Isabelle; Elaloui, Elimame

    2017-07-01

    A new nonlinear optical hybrid crystal 1,4-Diazbicyclo[222]octane oxonium tri-nitrates (DOTN), of the dimension 4×12×1 mm3. The crystal was grown using water as solvent at room temperature and crystal structure was determined by X-Ray diffraction respectively, this title compound was shown to crystallize in non-centrosymmetric trigonal system with space group P31c. The recorded FTIR spectrum has proven the presence of various functional groups in the grown crystal as well as the formation of DOTN. Besides, the thermal stability and melting temperature of the DOTN crystal were identified from the TG/DSC analysis. The suitability of this material for optical application was studied by non-linear optical (NLO) and UV-visible absorption techniques. Furthermore, the nonlinear optical property was analyzed by Kurtz-Perry powder technique and was 3.4 times than that of KDP (potassium dihydrogen phosphate) single crystals. The first hyperpolarizability of nitrate was determined by Second Harmonic light Scattering.

  19. RF deflecting cavity design for Berkeley ultrafast X-ray source

    Science.gov (United States)

    Li, D.; Corlett, J.

    2002-05-01

    Our proposed source for production of ultra-short (less than 100 fs FWHM) x-ray pulses utilizes a scheme for manipulation of the relatively long (2 ps) electron bunch in transverse phase-space, followed by compression of the emitted x-ray pulse in crystal optics. In order to compress the x-ray pulses, RF cavities operating in a dipole mode (TM110-like) are required to deflect the head and tail of a 2.5 GeV bunch in opposite directions. For a 2 ps duration electron bunch, an 8.5 MV deflecting voltage is required at a RF frequency of 3.9 GHz. In this paper, we will present a preliminary cavity design based on numerical simulations performed by MAFIA and URMEL codes. Seven-cell superconducting p mode dipole RF cavities are proposed to provide the necessary deflecting voltage. Due to the presence of beam iris, the mavities operate in a hybrid mode where TM and TE like modes co-exist. Even on mhe beam axis, both magnetic and electric fields contribute to the transverse mick. Lower order monopole modes (LOMs) in the cavities may cause energy spread of the electron beam and need to be damped. The effects of the LOMs on beam dynamics are estimated. Possible damping schemes will be discussed.

  20. RF deflecting cavity design for Berkeley ultrafast X-ray source

    Energy Technology Data Exchange (ETDEWEB)

    Li, Derun; Corlett, J.

    2002-05-30

    Our proposed source for production of ultra-short (less than 100 fs FWHM) x-ray pulses utilizes a scheme for manipulation of the relatively long ({approx}2 ps) electron bunch in transverse phase-space, followed by compression of the emitted x-ray pulse in crystal optics [1]. In order to compress the x-ray pulses, RF cavities operating in a dipole mode (TM{sub 110}-like) are required to deflect the head and tail of a 2.5 GeV bunch in opposite directions. For a 2 ps duration electron bunch, an 8.5 MV deflecting voltage is required at a RF frequency of 3.9 GHz. In this paper, we will present a preliminary cavity design based on numerical simulations performed by MAFIA and URMEL codes. Seven-cell superconducting {pi} mode dipole RF cavities are proposed to provide the necessary deflecting voltage. Due to the presence of beam iris, the cavities operate in a hybrid mode where TM and TE like modes co-exist. Even on the beam axis, both magnetic and electric fields contribute to the transverse kick. Lower order monopole modes (LOMs) in the cavities may cause energy spread of the electron beam and need to be damped. The effects of the LOMs on beam dynamics are estimated. Possible damping schemes will be discussed.

  1. Silica-graphene oxide hybrid composite particles and their electroresponsive characteristics.

    Science.gov (United States)

    Zhang, Wen Ling; Choi, Hyoung Jin

    2012-05-01

    Silica-graphene oxide (Si-GO) hybrid composite particles were prepared by the hydrolysis of tetraethyl orthosilicate (TEOS) in the presence of hydrophilic GO obtained from a modified Hummers method. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) images provided visible evidence of the silica nanoparticles grafted on the surface of GO, resulting in Si-GO hybrid composite particles. Energy dispersive X-ray spectroscopy (EDX) and X-ray diffraction (XRD) spectra indicated the coexistence of silica and GO in the composite particles. The Si-GO hybrid composite particles showed better thermal stability than that of GO according to thermogravimetric analysis (TGA). The electrorheological (ER) characteristics of the Si-GO hybrid composite based ER fluid were examined further by optical microscopy and a rotational rheometer in controlled shear rate mode under various electric field strengths. Shear stress curves were fitted using both conventional Bingham model and a constitutive Cho-Choi-Jhon model. The polarizability and relaxation time of the ER fluid from dielectric spectra measured using an LCR meter showed a good correlation with its ER characteristics.

  2. Scissors Mode in Gd Nuclei

    Directory of Open Access Journals (Sweden)

    Wu C.Y.

    2012-02-01

    Full Text Available Spectra of γ rays following neutron capture at isolated resonances of 6 stable Gd isotopes were measured with highly segmented BaF2 detector DANCE at the Los Alamos LANSCE spallation neutron source. The main emphasis was put on studying the γ-cascade decay of neutron resonances to get unique information on photon strength. An analysis of the accumulated γ-ray spectra within the extreme statistical model leads to an inescapable conclusion that scissors mode resonances are built not only on the ground-state, but also on excited levels in all product nuclei studied. The results on summed B(M1↑ strength and energy of the scissors mode are compared with systematics of scissors mode parameters for the ground-state transitions deduced from nuclear resonance fluorescence measurements. A specific feature of our experiments is the investigation of scissors mode of odd nuclei, for which the nuclear resonance fluorescence provides only limited information.

  3. Scissors Mode in Gd Nuclei

    Science.gov (United States)

    Kroll, J.; Baramsai, B.; Becker, J. A.; Bečvář, F.; Bredeweg, T. A.; Couture, A.; Chyzh, A.; Dashdorj, D.; Haight, R. C.; Jandel, M.; Krtička, M.; Mitchell, G. E.; O'Donnell, J. M.; Parker, W.; Rundberg, R. S.; Ullmann, J. L.; Vieira, G. J.; Walker, C. L.; Wilhelmy, J. B.; Wouters, J. M.; Wu, C. Y.

    2012-02-01

    Spectra of γ rays following neutron capture at isolated resonances of 6 stable Gd isotopes were measured with highly segmented BaF2 detector DANCE at the Los Alamos LANSCE spallation neutron source. The main emphasis was put on studying the γ-cascade decay of neutron resonances to get unique information on photon strength. An analysis of the accumulated γ-ray spectra within the extreme statistical model leads to an inescapable conclusion that scissors mode resonances are built not only on the ground-state, but also on excited levels in all product nuclei studied. The results on summed B(M1)↑ strength and energy of the scissors mode are compared with systematics of scissors mode parameters for the ground-state transitions deduced from nuclear resonance fluorescence measurements. A specific feature of our experiments is the investigation of scissors mode of odd nuclei, for which the nuclear resonance fluorescence provides only limited information.

  4. Hybrid Metaheuristics

    CERN Document Server

    2013-01-01

    The main goal of this book is to provide a state of the art of hybrid metaheuristics. The book provides a complete background that enables readers to design and implement hybrid metaheuristics to solve complex optimization problems (continuous/discrete, mono-objective/multi-objective, optimization under uncertainty) in a diverse range of application domains. Readers learn to solve large scale problems quickly and efficiently combining metaheuristics with complementary metaheuristics, mathematical programming, constraint programming and machine learning. Numerous real-world examples of problems and solutions demonstrate how hybrid metaheuristics are applied in such fields as networks, logistics and transportation, bio-medical, engineering design, scheduling.

  5. On Hybrid and mixed finite element methods

    Science.gov (United States)

    Pian, T. H. H.

    1981-01-01

    Three versions of the assumed stress hybrid model in finite element methods and the corresponding variational principles for the formulation are presented. Examples of rank deficiency for stiffness matrices by the hybrid stress model are given and their corresponding kinematic deformation modes are identified. A discussion of the derivation of general semi-Loof elements for plates and shells by the hybrid stress method is given. It is shown that the equilibrium model by Fraeijs de Veubeke can be derived by the approach of the hybrid stress model as a special case of semi-Loof elements.

  6. Hybrid intermediaries

    OpenAIRE

    Cetorelli, Nicola

    2014-01-01

    I introduce the concept of hybrid intermediaries: financial conglomerates that control a multiplicity of entity types active in the "assembly line" process of modern financial intermediation, a system that has become known as shadow banking. The complex bank holding companies of today are the best example of hybrid intermediaries, but I argue that financial firms from the "nonbank" space can just as easily evolve into conglomerates with similar organizational structure, thus acquiring the cap...

  7. Hybrid composites

    CSIR Research Space (South Africa)

    Jacob John, Maya

    2009-04-01

    Full Text Available effect was observed for the elongation at break of the hybrid composites. The impact strength of the hybrid composites increased with the addition of glass fibres. The tensile and impact properties of thermoplastic natural rubber reinforced short... panels made from conventional structural materials. Figure 3 illustrates the performance of cellular biocomposite panels against conventional systems used for building and residential construction, namely a pre- cast pre-stressed hollow core concrete...

  8. Visualizing hybridized quantum plasmons in coupled nanowires

    DEFF Research Database (Denmark)

    Andersen, Kirsten; Jensen, Kristian Lund; Mortensen, N. Asger

    2013-01-01

    We present full quantum-mechanical calculations of the hybridized plasmon modes of two nanowires at small separation, providing real-space visualization of the modes in the transition from the classical to the quantum tunneling regime. The plasmon modes are obtained as certain eigenfunctions...... of the dynamical dielectric function, which is computed using time-dependent density functional theory (TDDFT). For freestanding wires, the energy of both surface and bulk plasmon modes deviate from the classical result for low wire radii and high momentum transfer due to effects of electron spill-out, nonlocal...... response, and coupling to single-particle transitions. For the wire dimer, the shape of the hybridized plasmon modes are continuously altered with decreasing separation, and below 6 A˚, the energy dispersion of the modes deviate from classical results due to the onset of weak tunneling. Below 2-3 A...

  9. MODA - A hybrid atmospheric pollutant dispersion model

    Energy Technology Data Exchange (ETDEWEB)

    Favaron, M.; Oliveti Selmi, O. [Servizi Territorio srl, Milan (Italy); Sozzi, R. [Agenzia Regionale Protezione Ambiente (ARPA) Lazio, Rieti (Italy)

    2004-07-01

    MODA is a Gaussian-hybrid atmospheric dispersion model, intended for regulatory applications, and designed to meet the following requirements: ability to operate in complex terrain, standard use of a refined description of turbulence, operational efficiency (in terms of both speed and ease to change simulation parameters), ease of integration in modelling interfaces, output compatibility with the widely-used ISC3. MODA can operate in two modes: a standard mode, in which the pollutant dispersion is treated as Gaussian, and an advanced mode, in which the hybrid relations are used to compute the pollutant concentrations. (orig.)

  10. The design of the inelastic neutron scattering mode for the Extreme Environment Diffractometer with the 26 T High Field Magnet

    Energy Technology Data Exchange (ETDEWEB)

    Bartkowiak, Maciej, E-mail: maciej.bartkowiak@helmholtz-berlin.de; Stüßer, Norbert; Prokhnenko, Oleksandr

    2015-10-11

    The Extreme Environment Diffractometer is a neutron time-of-flight instrument, designed to work with a constant-field hybrid magnet capable of reaching fields over 26 T, unprecedented in neutron science; however, the presence of the magnet imposes both spatial and technical limitations on the surrounding instrument components. In addition to the existing diffraction and small-angle neutron scattering modes, the instrument will operate also in an inelastic scattering mode, as a direct time-of-flight spectrometer. In this paper we present the Monte Carlo ray-tracing simulations, the results of which illustrate the performance of the instrument in the inelastic-scattering mode. We describe the focussing neutron guide and the chopper system of the existing instrument and the planned design for the instrument upgrade. The neutron flux, neutron spatial distribution, divergence distribution and energy resolution are calculated for standard instrument configurations.

  11. Hybrid vehicle control

    Energy Technology Data Exchange (ETDEWEB)

    Shallvari, Iva; Velnati, Sashidhar; DeGroot, Kenneth P.

    2015-07-28

    A method and apparatus for heating a catalytic converter's catalyst to an efficient operating temperature in a hybrid electric vehicle when the vehicle is in a charge limited mode such as e.g., the charge depleting mode or when the vehicle's high voltage battery is otherwise charge limited. The method and apparatus determine whether a high voltage battery of the vehicle is incapable of accepting a first amount of charge associated with a first procedure to warm-up the catalyst. If it is determined that the high voltage battery is incapable of accepting the first amount of charge, a second procedure with an acceptable amount of charge is performed to warm-up the catalyst.

  12. Hybrid vehicle control

    Science.gov (United States)

    Shallvari, Iva; Velnati, Sashidhar; DeGroot, Kenneth P.

    2015-07-28

    A method and apparatus for heating a catalytic converter's catalyst to an efficient operating temperature in a hybrid electric vehicle when the vehicle is in a charge limited mode such as e.g., the charge depleting mode or when the vehicle's high voltage battery is otherwise charge limited. The method and apparatus determine whether a high voltage battery of the vehicle is incapable of accepting a first amount of charge associated with a first procedure to warm-up the catalyst. If it is determined that the high voltage battery is incapable of accepting the first amount of charge, a second procedure with an acceptable amount of charge is performed to warm-up the catalyst.

  13. Resolving colocalization of bacteria and metal(loid)s on plant root surfaces by combining fluorescence in situ hybridization (FISH) with multiple-energy micro-focused X-ray fluorescence (ME μXRF).

    Science.gov (United States)

    Honeker, Linnea K; Root, Robert A; Chorover, Jon; Maier, Raina M

    2016-12-01

    Metal(loid)-contamination of the environment due to anthropogenic activities is a global problem. Understanding the fate of contaminants requires elucidation of biotic and abiotic factors that influence metal(loid) speciation from molecular to field scales. Improved methods are needed to assess micro-scale processes, such as those occurring at biogeochemical interfaces between plant tissues, microbial cells, and metal(loid)s. Here we present an advanced method that combines fluorescence in situ hybridization (FISH) with synchrotron-based multiple-energy micro-focused X-ray fluorescence microprobe imaging (ME μXRF) to examine colocalization of bacteria and metal(loid)s on root surfaces of plants used to phytostabilize metalliferous mine tailings. Bacteria were visualized on a small root section using SytoBC nucleic acid stain and FISH probes targeting the domain Bacteria and a specific group (Alphaproteobacteria, Gammaproteobacteria, or Actinobacteria). The same root region was then analyzed for elemental distribution and metal(loid) speciation of As and Fe using ME μXRF. The FISH and ME μXRF images were aligned using ImageJ software to correlate microbiological and geochemical results. Results from quantitative analysis of colocalization show a significantly higher fraction of As colocalized with Fe-oxide plaques on the root surfaces (fraction of overlap 0.49±0.19) than to bacteria (0.072±0.052) (pbacteria that colocalized with metal(loid)s, Actinobacteria, known for their metal tolerance, had a higher correlation with both As and Fe than Alphaproteobacteria or Gammaproteobacteria. This method demonstrates how coupling these micro-techniques can expand our understanding of micro-scale interactions between roots, metal(loid)s and microbes, information that should lead to improved mechanistic models of metal(loid) speciation and fate. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. Failure Modes

    DEFF Research Database (Denmark)

    Jakobsen, K. P.; Burcharth, H. F.; Ibsen, Lars Bo;

    1999-01-01

    The present appendix contains the derivation of ten different limit state equations divided on three different failure modes. Five of the limit state equations can be used independently of the characteristics of the subsoil, whereas the remaining five can be used for either drained or undrained...

  15. Alpha Channeling with High-field Launch of Lower Hybrid Waves

    CERN Document Server

    Ochs, Ian E; Fisch, Nathaniel J

    2015-01-01

    Although lower hybrid waves are effective at driving currents in present-day tokamaks, they are expected to interact strongly with high-energy particles in extrapolating to reactors. In the presence of a radial alpha particle birth gradient, this interaction can take the form of wave amplification rather than damping. While it is known that this amplification more easily occurs when launching from the tokamak high-field side, the extent of this amplification has not been made quantitative. Here, by tracing rays launched from the high- field-side of a tokamak, the required radial gradients to achieve amplification are calculated for a temperature and density regime consistent with a hot-ion-mode fusion reactor. These simulations, while valid only in the linear regime of wave amplification, nonetheless illustrate the possibilities for wave amplification using high-field launch of the lower hybrid wave.

  16. The exposure of the hybrid detector of the Pierre Auger Observatory

    Science.gov (United States)

    Abreu, P.; Aglietta, M.; Ahn, E. J.; Allard, D.; Allekotte, I.; Allen, J.; Alvarez Castillo, J.; Alvarez-Muñiz, J.; Ambrosio, M.; Aminaei, A.; Anchordoqui, L.; Andringa, S.; Antičić, T.; Anzalone, A.; Aramo, C.; Arganda, E.; Arisaka, K.; Arqueros, F.; Asorey, H.; Assis, P.; Aublin, J.; Ave, M.; Avenier, M.; Avila, G.; Bäcker, T.; Badagnani, D.; Balzer, M.; Barber, K. B.; Barbosa, A. F.; Bardenet, R.; Barroso, S. L. C.; Baughman, B.; Beatty, J. J.; Becker, B. R.; Becker, K. H.; Bellétoile, A.; Bellido, J. A.; Benzvi, S.; Berat, C.; Bergmann, T.; Bertou, X.; Biermann, P. L.; Billoir, P.; Blanco, F.; Blanco, M.; Bleve, C.; Blümer, H.; Boháčová, M.; Boncioli, D.; Bonifazi, C.; Bonino, R.; Borodai, N.; Brack, J.; Brogueira, P.; Brown, W. C.; Bruijn, R.; Buchholz, P.; Bueno, A.; Burton, R. E.; Busca, N. G.; Caballero-Mora, K. S.; Caramete, L.; Caruso, R.; Castellina, A.; Catalano, O.; Cataldi, G.; Cazon, L.; Cester, R.; Chauvin, J.; Chiavassa, A.; Chinellato, J. A.; Chou, A.; Chudoba, J.; Clay, R. W.; Colombo, E.; Coluccia, M. R.; Conceição, R.; Contreras, F.; Cook, H.; Cooper, M. J.; Coppens, J.; Cordier, A.; Cotti, U.; Coutu, S.; Covault, C. E.; Creusot, A.; Criss, A.; Cronin, J.; Curutiu, A.; Dagoret-Campagne, S.; Dallier, R.; Dasso, S.; Daumiller, K.; Dawson, B. R.; de Almeida, R. M.; de Domenico, M.; de Donato, C.; de Jong, S. J.; de La Vega, G.; de Mello Junior, W. J. M.; de Mello Neto, J. R. T.; de Mitri, I.; de Souza, V.; de Vries, K. D.; Decerprit, G.; Del Peral, L.; Deligny, O.; Della Selva, A.; Dembinski, H.; Denkiewicz, A.; di Giulio, C.; Diaz, J. C.; Díaz Castro, M. L.; Diep, P. N.; Dobrigkeit, C.; D'Olivo, J. C.; Dong, P. N.; Dorofeev, A.; Dos Anjos, J. C.; Dova, M. T.; D'Urso, D.; Dutan, I.; Ebr, J.; Engel, R.; Erdmann, M.; Escobar, C. O.; Etchegoyen, A.; Facal San Luis, P.; Falcke, H.; Farrar, G.; Fauth, A. C.; Fazzini, N.; Ferguson, A. P.; Ferrero, A.; Fick, B.; Filevich, A.; Filipčič, A.; Fleck, I.; Fliescher, S.; Fracchiolla, C. E.; Fraenkel, E. D.; Fröhlich, U.; Fuchs, B.; Fulgione, W.; Gamarra, R. F.; Gambetta, S.; García, B.; García Gámez, D.; Garcia-Pinto, D.; Garrido, X.; Gascon, A.; Gelmini, G.; Gemmeke, H.; Gesterling, K.; Ghia, P. L.; Giaccari, U.; Giller, M.; Glass, H.; Gold, M. S.; Golup, G.; Gomez Albarracin, F.; Gómez Berisso, M.; Gonçalves, P.; Gonzalez, D.; Gonzalez, J. G.; Gookin, B.; Góra, D.; Gorgi, A.; Gouffon, P.; Gozzini, S. R.; Grashorn, E.; Grebe, S.; Grigat, M.; Grillo, A. F.; Guardincerri, Y.; Guarino, F.; Guedes, G. P.; Hague, J. D.; Hansen, P.; Harari, D.; Harmsma, S.; Harton, J. L.; Haungs, A.; Hebbeker, T.; Heck, D.; Herve, A. E.; Hojvat, C.; Holmes, V. C.; Homola, P.; Hörandel, J. R.; Horneffer, A.; Hrabovský, M.; Huege, T.; Insolia, A.; Ionita, F.; Italiano, A.; Jiraskova, S.; Kadija, K.; Kaducak, M.; Kampert, K. H.; Karhan, P.; Karova, T.; Kasper, P.; Kégl, B.; Keilhauer, B.; Keivani, A.; Kelley, J. L.; Kemp, E.; Kieckhafer, R. M.; Klages, H. O.; Kleifges, M.; Kleinfeller, J.; Knapp, J.; Koang, D.-H.; Kotera, K.; Krohm, N.; Krömer, O.; Kruppke-Hansen, D.; Kuehn, F.; Kuempel, D.; Kulbartz, J. K.; Kunka, N.; La Rosa, G.; Lachaud, C.; Lautridou, P.; Leão, M. S. A. B.; Lebrun, D.; Lebrun, P.; Leigui de Oliveira, M. A.; Lemiere, A.; Letessier-Selvon, A.; Lhenry-Yvon, I.; Link, K.; López, R.; Lopez Agüera, A.; Louedec, K.; Lozano Bahilo, J.; Lucero, A.; Ludwig, M.; Lyberis, H.; Maccarone, M. C.; Macolino, C.; Maldera, S.; Mandat, D.; Mantsch, P.; Mariazzi, A. G.; Marin, V.; Maris, I. C.; Marquez Falcon, H. R.; Marsella, G.; Martello, D.; Martin, L.; Martínez Bravo, O.; Mathes, H. J.; Matthews, J.; Matthews, J. A. J.; Matthiae, G.; Maurizio, D.; Mazur, P. O.; McEwen, M.; Medina-Tanco, G.; Melissas, M.; Melo, D.; Menichetti, E.; Menshikov, A.; Meurer, C.; Mičanović, S.; Micheletti, M. I.; Miller, W.; Miramonti, L.; Mollerach, S.; Monasor, M.; Monnier Ragaigne, D.; Montanet, F.; Morales, B.; Morello, C.; Moreno, E.; Moreno, J. C.; Morris, C.; Mostafá, M.; Mueller, S.; Muller, M. A.; Münchmeyer, M.; Mussa, R.; Navarra, G.; Navarro, J. L.; Navas, S.; Necesal, P.; Nellen, L.; Nhung, P. T.; Nierstenhoefer, N.; Nitz, D.; Nosek, D.; Nožka, L.; Nyklicek, M.; Oehlschläger, J.; Olinto, A.; Oliva, P.; Olmos-Gilbaja, V. M.; Ortiz, M.; Pacheco, N.; Pakk Selmi-Dei, D.; Palatka, M.; Pallotta, J.; Palmieri, N.; Parente, G.; Parizot, E.; Parra, A.; Parrisius, J.; Parsons, R. D.; Pastor, S.; Paul, T.; Pavlidou, V.; Payet, K.; Pech, M.; PeĶala, J.; Pelayo, R.; Pepe, I. M.; Perrone, L.; Pesce, R.; Petermann, E.; Petrera, S.; Petrinca, P.; Petrolini, A.; Petrov, Y.; Petrovic, J.; Pfendner, C.; Phan, N.; Piegaia, R.; Pierog, T.; Pimenta, M.; Pirronello, V.; Platino, M.; Ponce, V. H.; Pontz, M.; Privitera, P.; Prouza, M.; Quel, E. J.; Rautenberg, J.; Ravel, O.; Ravignani, D.; Revenu, B.; Ridky, J.; Riggi, S.; Risse, M.; Ristori, P.; Rivera, H.; Rivière, C.; Rizi, V.; Robledo, C.; Rodriguez, G.; Rodriguez Martino, J.; Rodriguez Rojo, J.; Rodriguez-Cabo, I.; Rodríguez-Frías, M. D.; Ros, G.; Rosado, J.; Rossler, T.; Roth, M.; Rouillé-D'Orfeuil, B.; Roulet, E.; Rovero, A. C.; Salamida, F.; Salazar, H.; Salina, G.; Sánchez, F.; Santander, M.; Santo, C. E.; Santos, E.; Santos, E. M.; Sarazin, F.; Sarkar, S.; Sato, R.; Scharf, N.; Scherini, V.; Schieler, H.; Schiffer, P.; Schmidt, A.; Schmidt, F.; Schmidt, T.; Scholten, O.; Schoorlemmer, H.; Schovancova, J.; Schovánek, P.; Schroeder, F.; Schulte, S.; Schüssler, F.; Schuster, D.; Sciutto, S. J.; Scuderi, M.; Segreto, A.; Semikoz, D.; Settimo, M.; Shadkam, A.; Shellard, R. C.; Sidelnik, I.; Sigl, G.; Śmiałkowski, A.; Šmída, R.; Snow, G. R.; Sommers, P.; Sorokin, J.; Spinka, H.; Squartini, R.; Stapleton, J.; Stasielak, J.; Stephan, M.; Strazzeri, E.; Stutz, A.; Suarez, F.; Suomijärvi, T.; Supanitsky, A. D.; Šuša, T.; Sutherland, M. S.; Swain, J.; Szadkowski, Z.; Tamashiro, A.; Tapia, A.; Tarutina, T.; Taşcău, O.; Tcaciuc, R.; Tcherniakhovski, D.; Tegolo, D.; Thao, N. T.; Thomas, D.; Tiffenberg, J.; Timmermans, C.; Tiwari, D. K.; Tkaczyk, W.; Todero Peixoto, C. J.; Tomé, B.; Tonachini, A.; Travnicek, P.; Tridapalli, D. B.; Tristram, G.; Trovato, E.; Tueros, M.; Ulrich, R.; Unger, M.; Urban, M.; Valdés Galicia, J. F.; Valiño, I.; Valore, L.; van den Berg, A. M.; Vargas Cárdenas, B.; Vázquez, J. R.; Vázquez, R. A.; Veberič, D.; Venters, T.; Verzi, V.; Videla, M.; Villaseñor, L.; Wahlberg, H.; Wahrlich, P.; Wainberg, O.; Warner, D.; Watson, A. A.; Weidenhaupt, K.; Weindl, A.; Westerhoff, S.; Whelan, B. J.; Wieczorek, G.; Wiencke, L.; Wilczyńska, B.; Wilczyński, H.; Will, M.; Williams, C.; Winchen, T.; Winders, L.; Winnick, M. G.; Wommer, M.; Wundheiler, B.; Yamamoto, T.; Younk, P.; Yuan, G.; Yushkov, A.; Zamorano, B.; Zas, E.; Zavrtanik, D.; Zavrtanik, M.; Zaw, I.; Zepeda, A.; Ziolkowski, M.; Pierre Auger Collaboration

    2011-01-01

    The Pierre Auger Observatory is a detector for ultra-high energy cosmic rays. It consists of a surface array to measure secondary particles at ground level and a fluorescence detector to measure the development of air showers in the atmosphere above the array. The "hybrid" detection mode combines the information from the two subsystems. We describe the determination of the hybrid exposure for events observed by the fluorescence telescopes in coincidence with at least one water-Cherenkov detector of the surface array. A detailed knowledge of the time dependence of the detection operations is crucial for an accurate evaluation of the exposure. We discuss the relevance of monitoring data collected during operations, such as the status of the fluorescence detector, background light and atmospheric conditions, that are used in both simulation and reconstruction.

  17. The exposure of the hybrid detector of the Pierre Auger Observatory

    Energy Technology Data Exchange (ETDEWEB)

    2010-06-01

    The Pierre Auger Observatory is a detector for ultra-high energy cosmic rays. It consists of a surface array to measure secondary particles at ground level and a fluorescence detector to measure the development of air showers in the atmosphere above the array. The 'hybrid' detection mode combines the information from the two subsystems. We describe the determination of the hybrid exposure for events observed by the fluorescence telescopes in coincidence with at least one water-Cherenkov detector of the surface array. A detailed knowledge of the time dependence of the detection operations is crucial for an accurate evaluation of the exposure. We discuss the relevance of monitoring data collected during operations, such as the status of the fluorescence detector, background light and atmospheric conditions, that are used in both simulation and reconstruction.

  18. Optimization of the composition of bimetallic core/shell Fe{sub 2}O{sub 3}/Au nanoparticles for MRI/CT dual-mode imaging

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Song; Qi, Yueyong; Yang, Hua; Gong, Mingfu; Zhang, Dong; Zou, Liguang, E-mail: zlgxqyy@163.com [Third Military Medical University, Department of Radiology, Xinqiao Hospital (China)

    2013-11-15

    Bimetallic core/shell Fe{sub 2}O{sub 3}/Au nanoparticles are promising candidate dual-mode contrast agents for magnetic resonance imaging (MRI) and computed tomography (CT) imaging. However, the gold coating on the hybrid nanoparticles (hybrids) affects the MRI and CT imaging quality. A thick gold nanoshell increases the X-ray attenuation effect but decreases the magnetic saturation of the hybrids. Therefore, we studied the effect of the Fe{sub 2}O{sub 3} and Au composition on these properties to find a suitable hybrid for MRI and CT imaging. Water-soluble, Au-coated magnetic nanoparticles were synthesized by iteratively reducing Au{sup 3+} onto the Fe{sub 2}O{sub 3} surface via hydroxylamine seeding. The properties of the hybrids obtained after different numbers of Au seeding cycles were studied using transmission electron microscopy, UV–Vis spectrophotometry, a vibrating swatch gaussmeter, MRI, CT, and an MTT assay. The hybrids obtained after three Au seeding cycles had an Fe{sub 2}O{sub 3}:Au molar ratio of 7.2:26.8, a mean diameter of 48.3 nm, a UV–Vis absorbance peak of 550 nm, a saturation magnetization of 49.0 emu/g, and no cytotoxicity at a concentration of 500 μg/mL after incubation with RAW 264.7 cells for up to 72 h. The hybrids obtained after three Au seeding cycles are the preferred candidates for MRI and CT applications because of their relatively high R2 relaxivity (95 mM{sup −1 }s{sup −1}) and X-ray attenuation (1.87 times that of iodine) compared to those of the other hybrids investigated in this study.

  19. Aminopyridinate-FI hybrids, their hafnium and titanium complexes, and their application in the living polymerization of 1-hexene.

    Science.gov (United States)

    Haas, Isabelle; Dietel, Thomas; Press, Konstantin; Kol, Moshe; Kempe, Rhett

    2013-10-11

    Based on two well-established ligand systems, the aminopyridinato (Ap) and the phenoxyimine (FI) ligand systems, new Ap-FI hybrid ligands were developed. Four different Ap-FI hybrid ligands were synthesized through a simple condensation reaction and fully characterized. The reaction of hafnium tetrabenzyl with all four Ap-FI hybrid ligands exclusively led to mono(Ap-FI) complexes of the type [(Ap-FI)HfBn2 ]. The ligands acted as tetradentate dianionic chelates. Upon activation with tris(pentafluorophenyl)borane, the hafnium-dibenzyl complexes led to highly active catalysts for the polymerization of 1-hexene. Ultrahigh molecular weights and extremely narrow polydispersities support the living nature of this polymerization process. A possible deactivation product of the hafnium catalysts was characterized by single-crystal X-ray analysis and is discussed. The coordination modes of these new ligands were studied with the help of model titanium complexes. The reaction of titanium(IV) isopropoxide with ligand 1 led to a mono(Ap-FI) complex, which showed the desired fac-mer coordination mode. Titanium (IV) isopropoxide reacted with ligand 4 to give a complex of the type [(ApH-FI)2 Ti(OiPr)2 ], which featured the ligand in its monoanionic form. The two titanium complexes were characterized by X-ray crystal-structure analysis. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. 基于网络信息技术的残疾人混合教学模式的实践与应用--以计算机文化基础课程为例%Practice and Application of Hybrid Teaching Mode for Disabled on Internet Technology-On Case of Computer Literature

    Institute of Scientific and Technical Information of China (English)

    孟香惠; 赖小乐; 李珊珊

    2012-01-01

      There are two meanings in“hybrid” teaching mode, one referring to different kinds of disabled learners, the other to the comprehensive application of various teaching and learning methods, which supplement each other and learn from each other. The hybrid teaching mode is not only suitable for the visual impaired, the deaf and dumb, and physical disabled learners to learn Computer Literature, but can be extended into learning other courses and become an effective teaching mode for the disabled.%  “混合”教学有两方面的含义:一方面是指不同类型的残疾学习者的混合;另一方面是指多种教与学手段相互补充,取长补短,综合应用。采用面向视障人士、聋哑人士、肢体残疾人士学习的“混合”教学模式,不仅适用于各类残疾人学习计算机文化基础课程,同时这种模式也能够推广到其他课程,成为残疾人教学的有效模式

  1. Study of cross-linking reactions induced by gamma rays in hybrid membranes of Bisphenol-A-Polysulfone and precipitated silica; Estudo da formacao de ligacoes cruzadas por irradiacao gama em membranas hibridas de Polissulfona Bisfenol-A e silica precipitada

    Energy Technology Data Exchange (ETDEWEB)

    Furtado Filho, Acacio Antonio M., E-mail: facacio@ctex.eb.br [Laboratorio de Quimica Militar, CTEx, Rio de Janeiro, RJ (Brazil); Gomes, Ailton de S.; Lopes, Lea; Benzi, Marcia R. [Instituto de Macromoleculas Professora Eloisa Mano, UFRJ, Rio de Janeiro, RJ (Brazil)

    2011-07-01

    In this work the bisphenol-A-polysulfone (PSF) was sulfonated using trimethyl silyl chlorosulfonate [(CH{sub 3}){sub 3}SiSO{sub 3}Cl] as a mild sulfonating agent in a homogeneous solution of dichloroethane. The sulfonation reaction was confirmed by acid-base titration and FTIR-spectroscopy analysis. The hybrid membranes were obtained by casting the sulfonated bisphenol-A-polysulfone (SPSF) and precipitated silica Tixosil{sup R} 333 solutions in N-N-dimethylacetamide. Cross-linking in the hybrid membranes was obtained by irradiation, with doses ranging from 5 to 30 kGy using gamma ray from a {sup 60}Co source. The water uptake and the swelling of the membranes were estimated by measuring the change in weight between dry and wet conditions. The conductivity of the membranes in acid form was measured with the ac impedance technique using a PGSTAT30 frequency response analyzer. The hybrid cross-linked membranes have conductivity close to 10-1 S.cm{sup -1} at 100% RH and 80 deg C. Electrochemical performances, thermo-mechanical stability and low cost make this cross-linked SPSF hybrid membrane an attractive material for fuel cells using a proton exchange membrane. (author)

  2. Gasoline hybrid pneumatic engine for efficient vehicle powertrain hybridization

    OpenAIRE

    Dimitrova, Zlatina; Maréchal, François

    2015-01-01

    The largest applied convertors in passenger cars are the internal combustion engines – gasoline, diesel, adapted also for operating on alternative fuels and hybrid modes. The number of components that are necessary to realize modern future propulsion system is inexorably increasing. The need for efficiency improvement of the vehicle energy system induces the search for an innovative methodology during the design process. In this article the compressed air is investigated as an innovative solu...

  3. Noise Effects in the Mode-Locked External Cavity Lasers

    Institute of Scientific and Technical Information of China (English)

    Nuran Dogru; M. Sadettin Ozyazici

    2003-01-01

    Effect of high level of spontaneous and carrier noise on mode-locked hybrid soliton pulse source and relative intensity noise is described. Transform limited pulses are not generated over a wide frequency range because of these noises.

  4. Control system for a hybrid powertrain system

    Energy Technology Data Exchange (ETDEWEB)

    Naqvi, Ali K.; Demirovic, Besim; Gupta, Pinaki; Kaminsky, Lawrence A.

    2014-09-09

    A vehicle includes a powertrain with an engine, first and second torque machines, and a hybrid transmission. A method for operating the vehicle includes operating the engine in an unfueled state, releasing an off-going clutch which when engaged effects operation of the hybrid transmission in a first continuously variable mode, and applying a friction braking torque to a wheel of the vehicle to compensate for an increase in an output torque of the hybrid transmission resulting from releasing the off-going clutch. Subsequent to releasing the off-going clutch, an oncoming clutch which when engaged effects operation of the hybrid transmission in a second continuously variable mode is synchronized. Subsequent to synchronization of the oncoming clutch, the oncoming clutch is engaged.

  5. Formes coopératives hybrids

    DEFF Research Database (Denmark)

    Spear, Roger

    2011-01-01

    la coopérative sociale. Il s’agit d’un modèle doublement « hybride », tant par son mode de gouvernance que par la diversité de ses pourvoyeurs de ressources. D’autres formes hybrides de coopératives se sont développées au cours de ces dernières années, en particulier dans le secteur des coopératives...

  6. The mode of inheritance in tetraploid cut roses

    NARCIS (Netherlands)

    Koning-Boucoiran, C.F.S.; Gitonga, V.W.; Yan, Z.; Dolstra, O.; Linden, van der C.G.; Schoot, van der J.; Uenk-Stunnenberg, G.E.; Verlinden, K.; Smulders, M.J.M.; Krens, F.A.; Maliepaard, C.A.

    2012-01-01

    Tetraploid hybrid tea roses (Rosa hybrida) represent most of the commercial cultivars of cut roses and form the basis for breeding programmes. Due to intensive interspecific hybridizations, modern cut roses are complex tetraploids for which the mode of inheritance is not exactly known. The segregati

  7. The mode of inheritance in tetraploid cut roses

    NARCIS (Netherlands)

    Koning-Boucoiran, C.F.S.; Gitonga, V.W.; Yan, Z.; Dolstra, O.; Linden, van der C.G.; Schoot, van der J.; Uenk-Stunnenberg, G.E.; Verlinden, K.; Smulders, M.J.M.; Krens, F.A.; Maliepaard, C.A.

    2012-01-01

    Tetraploid hybrid tea roses (Rosa hybrida) represent most of the commercial cultivars of cut roses and form the basis for breeding programmes. Due to intensive interspecific hybridizations, modern cut roses are complex tetraploids for which the mode of inheritance is not exactly known. The segregati

  8. Controllable growth and characterizations of hybrid spiral-like atomically thin molybdenum disulfide

    Science.gov (United States)

    Hao, Song; Yang, Bingchu; Gao, Yongli

    2016-10-01

    Monolayer MoS2 is an emerging two-dimensional semiconductor with wide-ranging potential applications in novel electronic and optoelectronic devices. Here, we reported controlled vapor phase growth of hybrid spiral-like MoS2 crystals investigated by multiple means of X-Ray photoemission spectroscopy, scanning electron microscopy, atomic force microscopy, kelvin probe force microscopy, Raman and Photoluminescence techniques. Morphological characterizations reveal an intriguing hybrid spiral-like MoS2 feature whose lower planes are AB Bernal stacking and upper structure is spiral. We ascribe the hybrid spiral-like structure to a screw dislocation drive growth mechanism owing to lower supersaturation and layer-by-layer growth mode. In addition, the electrostatic properties of MoS2 microflakes with hybrid spiral structures are obvious inhomogeneous and dependent on morphology manifested by kelvin probe force microscopy. Our work deepens the understanding of growth mechanisms of CVD-grown MoS2, which is also adoptable to other TMDC materials.

  9. Gravity localization on hybrid branes

    Energy Technology Data Exchange (ETDEWEB)

    Veras, D.F.S., E-mail: franklin@fisica.ufc.br [Universidade Federal do Ceará (UFC), Departamento de Física, Campus do Pici, Caixa Postal 6030, 60455-760, Fortaleza, Ceará (Brazil); Cruz, W.T., E-mail: wilamicruz@gmail.com [Instituto Federal de Educação, Ciência e Tecnologia do Ceará (IFCE), Campus Juazeiro do Norte, 63040-540 Juazeiro do Norte, Ceará (Brazil); Maluf, R.V., E-mail: r.v.maluf@fisica.ufc.br [Universidade Federal do Ceará (UFC), Departamento de Física, Campus do Pici, Caixa Postal 6030, 60455-760, Fortaleza, Ceará (Brazil); Almeida, C.A.S., E-mail: carlos@fisica.ufc.br [Universidade Federal do Ceará (UFC), Departamento de Física, Campus do Pici, Caixa Postal 6030, 60455-760, Fortaleza, Ceará (Brazil)

    2016-03-10

    This work deals with gravity localization on codimension-1 brane worlds engendered by compacton-like kinks, the so-called hybrid branes. In such scenarios, the thin brane behavior is manifested when the extra dimension is outside the compact domain, where the energy density is non-trivial, instead of asymptotically as in the usual thick brane models. The zero mode is trapped in the brane, as required. The massive modes, although not localized in the brane, have important phenomenological implications such as corrections to the Newton's law. We study such corrections in the usual thick domain wall and in the hybrid brane scenarios. By means of suitable numerical methods, we attain the mass spectrum for the graviton and the corresponding wavefunctions. The spectra possess the usual linearly increasing behavior from the Kaluza–Klein theories. Further, we show that the 4D gravitational force is slightly increased at short distances. The first eigenstate contributes highly for the correction to the Newton's law. The subsequent normalized solutions have diminishing contributions. Moreover, we find out that the phenomenology of the hybrid brane is not different from the usual thick domain wall. The use of numerical techniques for solving the equations of the massive modes is useful for matching possible phenomenological measurements in the gravitational law as a probe to warped extra dimensions.

  10. Gravity localization on hybrid branes

    Science.gov (United States)

    Veras, D. F. S.; Cruz, W. T.; Maluf, R. V.; Almeida, C. A. S.

    2016-03-01

    This work deals with gravity localization on codimension-1 brane worlds engendered by compacton-like kinks, the so-called hybrid branes. In such scenarios, the thin brane behavior is manifested when the extra dimension is outside the compact domain, where the energy density is non-trivial, instead of asymptotically as in the usual thick brane models. The zero mode is trapped in the brane, as required. The massive modes, although not localized in the brane, have important phenomenological implications such as corrections to the Newton's law. We study such corrections in the usual thick domain wall and in the hybrid brane scenarios. By means of suitable numerical methods, we attain the mass spectrum for the graviton and the corresponding wavefunctions. The spectra possess the usual linearly increasing behavior from the Kaluza-Klein theories. Further, we show that the 4D gravitational force is slightly increased at short distances. The first eigenstate contributes highly for the correction to the Newton's law. The subsequent normalized solutions have diminishing contributions. Moreover, we find out that the phenomenology of the hybrid brane is not different from the usual thick domain wall. The use of numerical techniques for solving the equations of the massive modes is useful for matching possible phenomenological measurements in the gravitational law as a probe to warped extra dimensions.

  11. Hybrid models in loop quantum cosmology

    Science.gov (United States)

    Elizaga Navascués, Beatriz; Martín-Benito, Mercedes; Mena Marugán, Guillermo A.

    2016-06-01

    In the framework of Loop Quantum Cosmology (LQC), inhomogeneous models are usually quantized by means of a hybrid approach that combines loop quantization techniques with standard quantum field theory methods. This approach is based on a splitting of the phase space in a homogeneous sector, formed by global, zero-modes and an inhomogeneous sector, formed by the remaining, infinite number of modes, that describe the local degrees of freedom. Then, the hybrid quantization is attained by adopting a loop representation for the homogeneous gravitational sector, while a Fock representation is used for the inhomogeneities. The zero-mode of the Hamiltonian constraint operator couples the homogeneous and inhomogeneous sectors. The hybrid approach, therefore, is expected to provide a suitable quantum theory in regimes where the main quantum effects of the geometry are those affecting the zero-modes, while the inhomogeneities, still being quantum, can be treated in a more conventional way. This hybrid strategy was first proposed for the simplest cosmological midisuperspaces: the Gowdy models, and it has been later applied to the case of cosmological perturbations. This paper reviews the construction and main applications of hybrid LQC.

  12. Broadband near-field enhancement in the macro-periodic and micro-random structure with a hybridized excitation of propagating Bloch-plasmonic and localized surface-plasmonic modes.

    Science.gov (United States)

    Lu, Haifei; Ren, Xingang; Sha, Wei E I; Ho, Ho-Pui; Choy, Wallace C H

    2015-10-28

    We demonstrate that the silver nanoplate-based macroscopically periodic (macro-periodic) and microscopically random (micro-random) structure has a broadband near-field enhancement as compared to conventional silver gratings. The specific field enhancement in a wide spectral range (from UV to near-infrared) originates from the abundance of localized surface-plasmonic (LSP) modes in the microscopically random distributed silver nanoplates and propagating Bloch-plasmonic (PBP) modes from the macroscopically periodic pattern. The characterization of polarization dependent spectral absorption, surface-enhanced Raman spectroscopy (SERS), as well as theoretical simulation was conducted to comprehensively understand the features of the broadband spectrum and highly concentrated near-field. The reported macro-periodic and micro-random structure may offer a new route for the design of plasmonic systems for photonic and optoelectronic applications.

  13. Long-range hybrid wedge plasmonic waveguide.

    Science.gov (United States)

    Zhang, Zhonglai; Wang, Jian

    2014-11-03

    We design a novel long-range hybrid wedge plasmonic (LRHWP) waveguide composed of two identical dielectric nanowires symmetrically placed on two opposed wedges of a diamond shaped metal wire. With strong coupling between the dielectric nanowire mode and long-range surface plasmon polariton (SPP) mode, both deep subwavelength mode confinement and low propagation loss are achieved. On one hand, when compared to the previous long-range hybrid SPP waveguide, LRHWP waveguide can achieve smaller mode size with similar propagation length; on the other hand, when compared to the previous hybrid wedge SPP waveguide, LRHWP waveguide can provide an order of magnitude longer propagation length with similar level of mode confinement. The designed LRHWP waveguide also features an overall advantage of one-order improvement of Figure of Merit. We further evaluate in detail the impacts of possible practical fabrication imperfections on the mode properties. The obtained results of mode properties show that the proposed LRHWP waveguide with an optimized wedge tip angle of 140 degree is fairly tolerant to practical fabrication errors in geometry parameters such as misalignment in the horizontal direction, asymmetry in the vertical direction, variation of wedge tip angle, tilt or rotation of metal wire, and variation of wedge tip curvature radius.

  14. MODE THEORY OF MULTILAYER WAVEGUIDE STRUCTURE WITH DISCONTINUITIES

    Institute of Scientific and Technical Information of China (English)

    Zong Weihua; Liang Changhong

    2003-01-01

    TEn mode (whose electric field is zero in the normal direction of theboundafiesbetween layers) and TMn mode (whose magnetic field is zero in the normal direction of the bound-aries between layers) are defined. Then conditions under which pure TEn (TMn) modes may existin multilayer waveguide structure with discontinuities are presented. E (H) step wavguides, ridgedwavguides, microstrip lines and fin lines all satisfy the conditions, and hold for TEn (TMn) mode.The conventional conclusion that ridged waveguides with inhomogeneous dielectric-slab loading,microstrip lines and fin lines only hold for hybrid modes is revised. Compared with hybrid modes,the number of unknown variations and matching equations is reduced by half for pure TEn (TMn)modes, and the computation cost is decreased dramatically.

  15. Hardware Assisted ROP Detection Mode (HARD Mode)

    Science.gov (United States)

    2013-08-01

    Distribution A. Cleared for public release; unlimited distribution. USAFA-CN-2013-457 Hardware Assisted ROP Detection Mode (HARD Mode) NATHANIEL HART...457 This report, "Hardware Assisted ROP Detection Mode (HARD Mode)" is presented as a competent treatment of the subj ect, worthy of publication. The...Technical 20120810-20121215 Hardware Assisted ROP Detection Mode (HARD Mode) NATHANIEL HART MICHAEL WINSTEAD MARTIN CARLISLE RODNEY LYKINS MICHAEL

  16. Effects of Mode Shares on Mode Choice

    OpenAIRE

    Carlos Carrion; Nebiyou Tilahun; David Levinson

    2011-01-01

    This study considers the influence of the knowledge of existing mode shares on travelers mode choice. This contrasts with traditional mode choice models, where the main objective is to predict the overall mode shares as the aggregate of individual mode choices according to variables encompassing attributes of the modes, and characteristics of the travelers. In this study, a computer-administered adaptive stated preference survey is developed and applied to a sample of subjects selected from t...

  17. Hybrid microelectronic technology

    Science.gov (United States)

    Moran, P.

    Various areas of hybrid microelectronic technology are discussed. The topics addressed include: basic thick film processing, thick film pastes and substrates, add-on components and attachment methods, thin film processing, and design of thick film hybrid circuits. Also considered are: packaging hybrid circuits, automating the production of hybrid circuits, application of hybrid techniques, customer's view of hybrid technology, and quality control and assurance in hybrid circuit production.

  18. Design, analysis and modeling of a novel hybrid powertrain system based on hybridized automated manual transmission

    Science.gov (United States)

    Wu, Guang; Dong, Zuomin

    2017-09-01

    Hybrid electric vehicles are widely accepted as a promising short to mid-term technical solution due to noticeably improved efficiency and lower emissions at competitive costs. In recent years, various hybrid powertrain systems were proposed and implemented based on different types of conventional transmission. Power-split system, including Toyota Hybrid System and Ford Hybrid System, are well-known examples. However, their relatively low torque capacity, and the drive of alternative and more advanced designs encouraged other innovative hybrid system designs. In this work, a new type of hybrid powertrain system based hybridized automated manual transmission (HAMT) is proposed. By using the concept of torque gap filler (TGF), this new hybrid powertrain type has the potential to overcome issue of torque gap during gearshift. The HAMT design (patent pending) is described in details, from gear layout and design of gear ratios (EV mode and HEV mode) to torque paths at different gears. As an analytical tool, mutli-body model of vehicle equipped with this HAMT was built to analyze powertrain dynamics at various steady and transient modes. A gearshift was decomposed and analyzed based basic modes. Furthermore, a Simulink-SimDriveline hybrid vehicle model was built for the new transmission, driveline and vehicle modular. Control strategy has also been built to harmonically coordinate different powertrain components to realize TGF function. A vehicle launch simulation test has been completed under 30% of accelerator pedal position to reveal details during gearshift. Simulation results showed that this HAMT can eliminate most torque gap that has been persistent issue of traditional AMT, improving both drivability and performance. This work demonstrated a new type of transmission that features high torque capacity, high efficiency and improved drivability.

  19. Nonlinear lower hybrid modeling in tokamak plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Napoli, F.; Schettini, G. [Università Roma Tre, Dipartimento di Ingegneria, Roma (Italy); Castaldo, C.; Cesario, R. [A