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Sample records for deg initial sinusoidal

  1. Effects of viscosity on shock-induced damping of an initial sinusoidal disturbance

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    A lack of reliable data treatment method has been for several decades the bottleneck of viscosity measurement by disturbance amplitude damping method of shock waves.In this work the finite difference method is firstly applied to obtain the numerical solutions for disturbance amplitude damping behavior of sinusoidal shock front in inviscid and viscous flow.When water shocked to 15 GPa is taken as an example,the main results are as follows:(1) For inviscid and lower viscous flows the numerical method gives results in good agreement with the analytic solutions under the condition of small disturbance(a0/λ=0.02);(2) For the flow of viscosity beyond 200 Pa s(η=κ) the analytic solution is found to overestimate obviously the effects of viscosity.It is attributed to the unreal pre-conditions of analytic solution by Miller and Ahrens;(3) The present numerical method provides an effective tool with more confidence to overcome the bottleneck of data treatment when the effects of higher viscosity in experiments of Sakharov and flyer impact are expected to be analyzed,because it can in principle simulate the development of shock waves in flows with larger disturbance amplitude,higher viscosity,and complicated initial flow.

  2. The effects of sinusoidal initial conditions on finite-thickness, HED shear flows

    Science.gov (United States)

    di Stefano, Carlos; Merritt, Elizabeth; Doss, Forrest; Desjardins, Tiffany; Flippo, Kirk; Kline, John; Loomis, Eric; Rasmus, Alex

    2016-10-01

    Hydrodynamic shear instability plays a role in any system in which shear flow across materials can be found, including in high-energy-density examples such as fusion plasmas and many astrophysical systems. In this work we describe experiments, performed on the OMEGA laser, exploring shear instability through the use of carefully-controlled, single-mode initial conditions. A novel aspect of these experiments is that they employ counter-propagating shocks separated by a collimating layer. This produces a region of shear flow in which the pressure is balanced across flow, simplifying theoretical analysis and modeling. We discuss two interesting behaviors seen in these experiments. First, at early times, radiographs show the expansion of the collimator and the spectral evolution of the initial perturbation features from laser-drive heating of the material. The evolved features then couple to the primary shear instability we seek to probe. Second, at late times, we observe the persistence of a coherent long-wavelength mode in the mixing layer, driven by the imposed surface perturbation, which resonates with and the length scale introduced by the finite thickness of the collimator.

  3. The XMM-BCS galaxy cluster survey: I. The X-ray selected cluster catalog from the initial 6 deg$^2$

    CERN Document Server

    Šuhada, R; Böhringer, H; Mohr, J J; Chon, G; Finoguenov, A; Fassbender, R; Desai, S; Armstrong, R; Zenteno, A; Barkhouse, W A; Bertin, E; Buckley-Geer, E J; Hansen, S M; High, F W; Lin, H; Mühlegger, M; Ngeow, C C; Pierini, D; Pratt, G W; Verdugo, M; Tucker, D L

    2011-01-01

    The XMM-Newton - Blanco Cosmology Survey project (XMM-BCS) is a coordinated X-ray, optical and mid-infrared cluster survey in a field also covered by Sunyaev-Zel'dovich effect surveys by the South Pole Telescope and the Atacama Cosmology Telescope. The aim of the project is to study the cluster population in a 14 deg$^2$ field. In this work, we present a catalog of 46 X-ray selected clusters from the initial 6 deg$^2$ survey core. We describe the XMM-BCS source detection pipeline and derive physical properties of the clusters. We provide photometric redshift estimates derived from the BCS imaging data and spectroscopic redshift measurements for a low redshift subset of the clusters. We derive the cluster log N - log S relation using an approximation to the survey selection function and find it in good agreement with previous studies. We carry out an initial comparison between X-ray luminosity derived masses and masses from optical estimators from the Southern Cosmology Survey for a subset of the cluster sampl...

  4. THE MASSIVE AND DISTANT CLUSTERS OF WISE SURVEY. II. INITIAL SPECTROSCOPIC CONFIRMATION OF z ∼ 1 GALAXY CLUSTERS SELECTED FROM 10,000 deg{sup 2}

    Energy Technology Data Exchange (ETDEWEB)

    Stanford, S. A. [Department of Physics, University of California, One Shields Avenue, Davis, CA 95616 (United States); Gonzalez, Anthony H.; Gettings, Daniel P. [Department of Astronomy, University of Florida, 211 Bryant Space Center, Gainesville, FL 32611 (United States); Brodwin, Mark [Department of Physics and Astronomy, University of Missouri, 5110 Rockhill Road, Kansas City, MO 64110 (United States); Eisenhardt, Peter R. M.; Stern, Daniel [Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove, Pasadena, CA 91109 (United States); Wylezalek, Dominika [European Southern Observatory, Karl-Schwarzschildstrasse 2, D-85748, Garching bei Munchen (Germany)

    2014-08-01

    We present optical and infrared imaging and optical spectroscopy of galaxy clusters which were identified as part of an all-sky search for high-redshift galaxy clusters, the Massive and Distant Clusters of WISE Survey (MaDCoWS). The initial phase of MaDCoWS combined infrared data from the all-sky data release of the Wide-field Infrared Survey Explorer (WISE) with optical data from the Sloan Digital Sky Survey to select probable z ∼ 1 clusters of galaxies over an area of 10,000 deg{sup 2}. Our spectroscopy confirms 19 new clusters at 0.7 < z < 1.3, half of which are at z > 1, demonstrating the viability of using WISE to identify high-redshift galaxy clusters. The next phase of MaDCoWS will use the greater depth of the AllWISE data release to identify even higher redshift cluster candidates.

  5. Mechanism of <1 1 2>/3 slip initiation and anisotropy of {gamma}' phase in CMSX-4 during creep at 750 deg. C and 750 MPa

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Q.Z.; Knowles, D.M

    2003-09-15

    Creep deformation defects from tensile creep tests carried out at 750 deg. C under 750 MPa in the approximate orientations [1-bar 3 6], [0 0 1], [0 1 1] and [1 1 1] for CMSX-4 single crystals have been identified carefully, using transmission electron microscope combined with computer simulated microimages. A series of results have been obtained. (i) It was confirmed that <1 1 2>/3 slip in {gamma}' phase mainly involved the reaction and dissociation of two <1 1 0>/2 dislocations which had different Burgers vectors and met at the {gamma}/{gamma}' interfaces where the product <1 1 2>/6 partials were trapped. (ii) At 750 deg. C and 750 MPa, the selectivity among {l_brace}1 1 1{r_brace}<1 1 2> slip systems was sensitive to Schmid factors. The reason for the anisotropy was that the resolved shear stress of highly stressed {l_brace}1 1 1{r_brace}<1 1 2> slip systems in the [1-bar 3 6], [0 0 1] and [0 1 1] orientations were just around the critical resolved shear stress of <1 1 2>/3 faulting in {gamma}' phase which was estimated to be {approx}300 MPa. Hence, a slight decrease of a RSS could switch off the operation of a {l_brace}1 1 1{r_brace}<1 1 2> slip system, or vice versa. (iii) The activation of {l_brace}1 1 1{r_brace}<1 1 0> slip systems was a necessary but not sufficient factor of initiating <1 1 2>/3 faulting in the {gamma}' particles. The operation of <1 1 2>/3 slip and density of superlattice stacking faults were controlled by the RSSs acting on those {l_brace}1 1 1{r_brace}<1 1 2> slip systems.

  6. Noise upon the Sinusoids

    DEFF Research Database (Denmark)

    Jensen, Karl Kristoffer

    2005-01-01

    Sinusoids are used for making harmonic and other sounds. In order to having life in the sounds and adding a wide variety of noises, irregularities are inserted in the frequency and amplitudes. A simple and intuitive noise model is presented, consisting of a low-pass filtered noise, and having...... control for strength and bandwidth. The noise is added on the frequency and amplitudes of the sinusoids, and the resulting irregularity’s (jitter and shimmer) bandwidth is derived. This, together with an overview of investigation methods of the jitter and shimmer results in an analysis of the necessary...... samplerate of the shimmer and jitter. A harmonic model introduces individual and common irregularity, and adds a correlation control. The model has been implemented in max/msp and used in contemporary music compositions....

  7. Noise upon the sinusoids

    DEFF Research Database (Denmark)

    Jensen, Karl Kristoffer

    2005-01-01

    Sinusoids are used for making harmonic and other Sounds. In order to having life in the sounds and adding a wide variety of noises, irregularities are inserted in the frequency and amplitudes. A simple and intuitive noise model is presented, consisting of a low-pass filtered noise, and having...... control for strength and bandwidth. The noise is added on the frequency and amplitudes of the sinusoids, and the resulting irregularity's (jitter and shimmer) bandwidth is derived. This, together with an overview of investigation methods of the jitter and shimmer results in an analysis of the necessary...... samplerate of the shimmer and jitter. A harmonic model introduces individual and common irregularity, and adds a correlation control. The model has been implemented in max/msp and used in contemporary Music compositions....

  8. The XMM-BCS galaxy cluster survey: I. The X-ray selected cluster catalog from the initial 6 deg$^2$

    Energy Technology Data Exchange (ETDEWEB)

    Suhada, R.; /Munich, Tech. U. /Munich U.; Song, J.; /Michigan U.; Bohringer, H.; /Munich, Tech. U.; Mohr, J.J.; /Munich, Tech. U. /Munich U. /Munich, Tech. U., Universe; Chon, G.; /Munich, Tech. U.; Finoguenov, A.; /Munich, Tech. U. /CSST, Baltimore; Fassbender, R.; /Munich, Tech. U. /CSST, Baltimore; Desai, S.; /Munich U. /Illinois U., Urbana; Armstrong, R.; /Illinois U., Urbana; Zenteno, A.; /Munich U. /Munich, Tech. U., Universe; Barkhouse, W.A.; /North Dakota U. /Paris, Inst. Astrophys.

    2011-11-01

    The XMM-Newton - Blanco Cosmology Survey project (XMM-BCS) is a coordinated X-ray, optical and mid-infrared cluster survey in a field also covered by Sunyaev-Zel dovich effect (SZE) surveys by the South Pole Telescope and the Atacama Cosmology Telescope. The aim of the project is to study the cluster population in a 14 deg{sup 2} field (center: {alpha} {approx} 23:29:18.4, {delta} {approx} -54:40:33.6). The uniform multi-wavelength coverage will also allow us for the first time to comprehensively compare the selection function of the different cluster detection approaches in a single test field and perform a cross-calibration of cluster scaling relations. In this work, we present a catalog of 46 X-ray selected clusters from the initial 6 deg{sup 2} survey core.We describe the XMM-BCS source detection pipeline and derive physical properties of the clusters. We provide photometric redshift estimates derived from the BCS imaging data and spectroscopic redshift measurements for a low redshift subset of the clusters. The photometric redshift estimates are found to be unbiased and in good agreement with the spectroscopic values. Our multi-wavelength approach gives us a comprehensive look at the cluster and group population up to redshifts z {approx} 1. The median redshift of the sample is 0.47 and the median mass M{sub 500} {approx} 1 x 10{sup 14} M{sub {circle_dot}} ({approx} 2 keV). From the sample, we derive the cluster log N - log S using an approximation to the survey selection function and find it in good agreement with previous studies. We compare optical mass estimates from the Southern Cosmology Survey available for part of our cluster sample with our estimates derived from the X-ray luminosity. Weak lensing masses available for a subset of the cluster sample are in agreement with our estimates. Optical masses based on cluster richness and total optical luminosity are found to be significantly higher than the X-ray values. The present results illustrate the

  9. Parameter Estimation of Noise Corrupted Sinusoids

    CERN Document Server

    O'Brien, Francis J; Johnnie, Nathan

    2011-01-01

    Existing algorithms for fitting the parameters of a sinusoid to noisy discrete time observations are not always successful due to initial value sensitivity and other issues. This paper demonstrates the techniques of FIR filtering, Fast Fourier Transform, and nonlinear least squares minimization as useful in the parameter estimation of amplitude, frequency and phase exemplified for a low-frequency time-delayed sinusoid describing simple harmonic motion. Alternative means are described for estimating frequency and phase angle. An autocorrelation function for harmonic motion is also derived.

  10. Sinusoids theory and technological applications

    CERN Document Server

    Kythe, Prem K

    2014-01-01

    A Complete Treatment of Current Research Topics in Fourier Transforms and Sinusoids Sinusoids: Theory and Technological Applications explains how sinusoids and Fourier transforms are used in a variety of application areas, including signal processing, GPS, optics, x-ray crystallography, radioastronomy, poetry and music as sound waves, and the medical sciences. With more than 200 illustrations, the book discusses electromagnetic force and sychrotron radiation comprising all kinds of waves, including gamma rays, x-rays, UV rays, visible light rays, infrared, microwaves, and radio waves. It also covers topics of common interest, such as quasars, pulsars, the Big Bang theory, Olbers' paradox, black holes, Mars mission, and SETI.The book begins by describing sinusoids-which are periodic sine or cosine functions-using well-known examples from wave theory, including traveling and standing waves, continuous musical rhythms, and the human liver. It next discusses the Fourier series and transform in both continuous and...

  11. Sensorless optimal sinusoidal brushless direct current for hard disk drives

    Science.gov (United States)

    Soh, C. S.; Bi, C.

    2009-04-01

    Initiated by the availability of digital signal processors and emergence of new applications, market demands for permanent magnet synchronous motors have been surging. As its back-emf is sinusoidal, the drive current should also be sinusoidal for reducing the torque ripple. However, in applications like hard disk drives, brushless direct current (BLDC) drive is adopted instead of sinusoidal drive for simplification. The adoption, however, comes at the expense of increased harmonics, losses, torque pulsations, and acoustics. In this paper, we propose a sensorless optimal sinusoidal BLDC drive. First and foremost, the derivation for an optimal sinusoidal drive is presented, and a power angle control scheme is proposed to achieve an optimal sinusoidal BLDC. The scheme maintains linear relationship between the motor speed and drive voltage. In an attempt to execute the sensorless drive, an innovative power angle measurement scheme is devised, which takes advantage of the freewheeling diodes and measures the power angle through the detection of diode voltage drops. The objectives as laid out will be presented and discussed in this paper, supported by derivations, simulations, and experimental results. The proposed scheme is straightforward, brings about the benefits of sensorless sinusoidal drive, negates the need for current sensors by utilizing the freewheeling diodes, and does not incur additional cost.

  12. Il teatro degli spiriti.

    Directory of Open Access Journals (Sweden)

    Chiara Pussetti

    2013-07-01

    Full Text Available Questo saggio è dedicato a un culto di possessione, in cui tutte ledonne, investite dagli spiriti degli uomini morti prima dell’iniziazione, compiono un percorso iniziatico parallelo a quello maschile, consentendo a queste anime, potenzialmente pericolose, di completare il cammino che non hanno potuto percorrere da vivi e quindi di raggiungere serenamente il mondo dei morti, come antenati protettori del villaggio

  13. Electronically Tunable Sinusoidal Oscillator Circuit

    Directory of Open Access Journals (Sweden)

    Sudhanshu Maheshwari

    2012-01-01

    Full Text Available This paper presents a novel electronically tunable third-order sinusoidal oscillator synthesized from a simple topology, employing current-mode blocks. The circuit is realized using the active element: Current Controlled Conveyors (CCCIIs and grounded passive components. The new circuit enjoys the advantages of noninteractive electronically tunable frequency of oscillation, use of grounded passive components, and the simultaneous availability of three sinusoidal voltage outputs. Bias current generation scheme is given for the active elements used. The circuit exhibits good high frequency performance. Nonideal and parasitic study has also been carried out. Wide range frequency tuning is shown with the bias current. The proposed theory is verified through extensive PSPICE simulations using 0.25 μm CMOS process parameters.

  14. Ingegneria degli acquiferi

    CERN Document Server

    Molfetta, Antonio

    2012-01-01

    Il testo fornisce le conoscenze necessarie per affrontare, con un approccio quantitativo, i molteplici aspetti connessi al flusso delle risorse idriche sotterranee (acque di falda) e alla propagazione e bonifica di contaminanti nei sistemi acquiferi. Vengono illustrate le proprietà fondamentali che definiscono la capacità di immagazzinamento, trasporto e rilascio dell’acqua negli acquiferi, e successivamente, descritte le metodiche per la determinazione di tali parametri tramite l’esecuzione e l’interpretazione di prove di falda, di pozzo e di laboratorio. A partire dalla classificazione chimico fisica-tossicologica dei contaminanti vengono, quindi, analizzati i meccanismi di propagazione e illustrate le soluzioni analitiche dell’equazione del trasporto di massa nei mezzi porosi. L’ultima parte del testo è dedicata alla caratterizzazione e bonifica degli acquiferi contaminati. Il testo è rivolto sia agli studenti universitari, sia ai professionisti che debbano affrontare con un approccio quantit...

  15. Influência do substrato na germinação e desenvolvimento inicial de plantas de maracujazeiro amarelo (Passiflora edulis Sims f. flavicarpa Deg Effects of substrate on germination and initial growth of yellow passion fruit (Passiflora edulis Sims f. flavicarpa Deg

    Directory of Open Access Journals (Sweden)

    Américo Wagner Júnior

    2006-08-01

    Full Text Available Na maioria das vezes, a muda de maracujazeiro amarelo é produzida a partir de sementes. Neste sentido, o êxito no estabelecimento da cultura depende de vários fatores, entre os quais está a utilização de sementes de boa qualidade e a escolha do melhor substrato. Com este trabalho, objetivou-se avaliar a influência de quatro substratos na germinação e desenvolvimento inicial de plantas de maracujazeiro amarelo (Passiflora edulis Sims f. flavicarpa Deg, cultivar IAC 277. O trabalho foi realizado no Departamento de Fitotecnia, da Universidade Federal de Viçosa, de abril a junho de 2004. Foram testados quatro substratos: Plantmax® ; Plantmax® + Areia (1:1 v/v; Plantmax® + Latossolo Vermelho (1:1 v/v; Plantmax® + Latossolo Vermelho + Areia (1:1:1 v/v. Foi utilizado o delineamento experimental em blocos casualizados, com quatro tratamentos e três repetições, considerando-se como unidade experimental, cada 5 recipientes plásticos. Após 48 dias da semeadura foram analisados: porcentagem de germinação; comprimento total, da parte aérea e de raiz das plantas e a massa da matéria seca total das plantas. Os dados foram submetidos à análise de variância e ao teste de Tukey (a = 0,05. Pelos resultados obtidos não foram observadas diferenças significativas entre os substratos em todas as variáveis analisadas. Com isso, conclui-se que os quatros substratos utilizados proporcionaram condições adequadas à germinação e ao desenvolvimento inicial de plantas de maracujazeiro amarelo, cultivar IAC 277.Most of the time, seedlings of yellow passion fruit are produced from seeds. The success in the establishment of the culture depends on several factors, such as the use of seeds of good quality and choice of the best substrate. This work had the objective of evaluating the influence of four substrates on the germination and initial seedling growth of yellow passion fruit (Passiflora edulis Sims f. flavicarpa Deg, cv. IAC 277.The work

  16. Single ICCII Sinusoidal Oscillators Employing Grounded Capacitors

    Directory of Open Access Journals (Sweden)

    J. W. Horng

    2011-09-01

    Full Text Available Two inverting second-generation current conveyors (ICCII based sinusoidal oscillators are presented. The first sinusoidal oscillator is composed of one ICCII, two grounded capacitors and two resistors. The oscillation condition and oscillation frequency can be orthogonally controllable. The second sinusoidal oscillator is composed of one ICCII, two grounded capacitors and three resistors. The oscillation condition and oscillation frequency can be independently controllable through different resistors.

  17. Photoluminescence and phosphorescence properties of MAl{sub 2}O{sub 4}:Eu{sup 2+}, Dy{sup 3+} (M=Ca, Ba, Sr) phosphors prepared at an initiating combustion temperature of 500 deg. C

    Energy Technology Data Exchange (ETDEWEB)

    Mothudi, B.M., E-mail: mothudibm@qwa.uovs.ac.z [Department of Physics, University of the Free State, P.O. Box 339, Bloemfontein, ZA 9300 (South Africa); Ntwaeaborwa, O.M. [Department of Physics, University of the Free State, P.O. Box 339, Bloemfontein, ZA 9300 (South Africa); Botha, J.R. [Department of Physics, Nelson Mandela Metropolitan University, Port Elizabeth, ZA 6031 (South Africa); Swart, H.C., E-mail: swarthc.sci@ufs.ac.z [Department of Physics, University of the Free State, P.O. Box 339, Bloemfontein, ZA 9300 (South Africa)

    2009-12-01

    Eu{sup 2+} and Dy{sup 3+} co-doped calcium aluminate, barium aluminate and strontium aluminate phosphors were synthesized at an initiating combustion temperature of 500 deg. C using urea as an organic fuel. The crystallinity of the phosphors was investigated by using X-ray diffraction (XRD) and the morphology was determined by a scanning electron microscope (SEM). The low temperature monoclinic structure for both CaAl{sub 2}O{sub 4} and SrAl{sub 2}O{sub 4} and the hexagonal structure of BaAl{sub 2}O{sub 4} were observed. The effect of the host materials on the photoluminescence (PL) and phosphorescence properties were investigated by using a He-Cd Laser and a Cary Eclipse fluorescence spectrophotometer, respectively. The broad band emission spectra observed at 449 nm for CaAl{sub 2}O{sub 4}:Eu{sup 2+}, Dy{sup 3+}, 450 nm (with a shoulder-peak at 500 nm) for BaAl{sub 2}O{sub 4}:Eu{sup 2+}, Dy{sup 3+} and 528 nm for SrAl{sub 2}O{sub 4}:Eu{sup 2+}, Dy{sup 3+} are attributed to the 4f{sup 6}5d{sup 1} to 4f{sup 7} transition in the Eu{sup 2+} ion in the different hosts.

  18. Sinusoidal masks for single channel speech separation

    DEFF Research Database (Denmark)

    Mowlaee, Pejman; Christensen, Mads Græsbøll; Jensen, Søren Holdt

    2010-01-01

    In this paper we present a new approach for binary and soft masks used in single-channel speech separation. We present a novel approach called the sinusoidal mask (binary mask and Wiener filter) in a sinusoidal space. Theoretical analysis is presented for the proposed method, and we show...

  19. Mathematical Models of the Sinusoidal Screen Family

    Directory of Open Access Journals (Sweden)

    Tajana Koren

    2011-06-01

    Full Text Available In this paper we will define a family of sinusoidal screening elements and explore the possibilities of their application in graphic arts, securities printing and design solutions in photography and typography editing. For this purpose mathematical expressions of sinusoidal families were converted into a Postscript language. The introduction of a random variable results in a countless number of various mutations which cannot be repeated without knowing the programming code itself. The use of the family of screens in protection of securities is thus of great importance. Other possible application of modulated sinusoidal screens is related to the large format color printing. This paper will test the application of sinusoidal screens in vector graphics, pixel graphics and typography. The development of parameters in the sinusoidal screen element algorithms gives new forms defined within screening cells with strict requirements of coverage implementation. Individual solutions include stochastic algorithms, as well as the autonomy of screening forms in regard to multicolor printing channels.

  20. Linear sinusoidal phase-shifting method resistant to non-sinusoidal phase error

    Institute of Scientific and Technical Information of China (English)

    Haihua Cui; Wenhe Liao; Ning Dai; Xiaosheng Cheng

    2012-01-01

    Non-sinusoidal phase error is common in structured light three-dimensional (3D) shape measurement system, thus we perform theoretical and experimental analyses of such error. The number of non-sinusoidal waveform errors in a 2tt phase period is the same as the number of steps of the phase-shifting algorithm; no errors occur within the one-phase period. Based on our findings, a new structured light method, the linear sinusoidal phase-shifting method (LSPS), that is resistant to non-sinusoidal phase error is proposed. Experiments show that the non-sinusoidal waveform error is reduced to an almost negligible level (0.001 rad) using the proposed LSPS.%Non-sinusoidal phase error is common in structured light three-dimensional (3D) shape measurement system,thus we perform theoretical and experimental analyses of such error.The number of non-sinusoidal waveform errors in a 2π phase period is the same as the number of steps of the phase-shifting algorithm; no errors occur within the one-phase period.Based on our findings,a new structured light method,the linear sinusoidal phase-shifting method (LSPS),that is resistant to non-sinusoidal phase error is proposed.Experiments show that the non-sinusoidal waveform error is reduced to an almost negligible level (0.001 rad)using the proposed LSPS.

  1. Encryption in Chaotic Systems with Sinusoidal Excitations

    Directory of Open Access Journals (Sweden)

    G. Obregón-Pulido

    2014-01-01

    Full Text Available In this contribution an encryption method using a chaotic oscillator, excited by “n” sinusoidal signals, is presented. The chaotic oscillator is excited by a sum of “n” sinusoidal signals and a message. The objective is to encrypt such a message using the chaotic behavior and transmit it, and, as the chaotic system is perturbed by the sinusoidal signal, the transmission security could be increased due to the effect of such a perturbation. The procedure is based on the regulation theory and consider that the receiver knows the frequencies of the perturbing signal, with this considerations the algorithm estimates the excitation in such a way that the receiver can cancel out the perturbation and all the undesirable dynamics in order to produce only the message. In this way we consider that the security level is increased.

  2. Cavitation on hydrofoils with sinusoidal leading edge

    Science.gov (United States)

    Johari, H.

    2015-12-01

    Cavitation characteristics of hydrofoils with sinusoidal leading edge were examined experimentally at a Reynolds number of 7.2 × 105. The hydrofoils had an underlying NACA 634-021 profile and an aspect ratio of 4.3. The sinusoidal leading edge geometries included three amplitudes of 2.5%, 5%, and 12% and two wavelengths of 25% and 50% of the mean chord length. Results revealed that cavitation on the leading edge-modified hydrofoils existed in pockets behind the troughs whereas the baseline hydrofoil produced cavitation along its entire span. Moreover, cavitation on the modified hydrofoils appeared at consistently lower angles of attack than on the baseline hydrofoil.

  3. Human comfort in relation to sinusoidal vibration

    Science.gov (United States)

    Jones, B.; Rao, B. K. N.

    1975-01-01

    An investigation was made to assess the overall subjective comfort levels to sinusoidal excitations over the range 1 to 19 Hz using a two axis electrohydraulic vibration simulator. Exposure durations of 16 minutes, 25 minutes, 1 hour, and 2.5 hours have been considered. Subjects were not exposed over such durations, but were instructed to estimate the overall comfort levels preferred had they been constantly subjected to vibration over such durations.

  4. Biphase sinusoidal oscillator based on negative resistor.

    Science.gov (United States)

    Bayard, Jean

    2010-06-01

    This paper describes a biphase sinusoidal generator which provides two signals: v(ref)=V(M) sin(omegat) and v(out)=V(M) sin(omegat+DeltaPhi), where DeltaPhi is in the range 0, pi/2 or -pi/2, 0 and is not dependent on the frequency value. It is based on a negative resistor and it requires very few components. SPICE simulations and measurements on an experimental setup confirm the theoretical analysis.

  5. Force Sensor Characterization Under Sinusoidal Excitations

    Directory of Open Access Journals (Sweden)

    Nieves Medina

    2014-10-01

    Full Text Available The aim in the current work is the development of a method to characterize force sensors under sinusoidal excitations using a primary standard as the source of traceability. During this work the influence factors have been studied and a method to minimise their contributions, as well as the corrections to be performed under dynamic conditions have been established. These results will allow the realization of an adequate characterization of force sensors under sinusoidal excitations, which will be essential for its further proper use under dynamic conditions. The traceability of the sensor characterization is based in the direct definition of force as mass multiplied by acceleration. To do so, the sensor is loaded with different calibrated loads and is maintained under different sinusoidal accelerations by means of a vibration shaker system that is able to generate accelerations up to 100 m/s2 with frequencies from 5 Hz up to 2400 Hz. The acceleration is measured by means of a laser vibrometer with traceability to the units of time and length. A multiple channel data acquisition system is also required to simultaneously acquire the electrical output signals of the involved instrument in real time.

  6. Cloning and sequencing the degS-degU operon from an alkalophilic Bacillus-brevis

    CSIR Research Space (South Africa)

    Louw, M

    1994-10-01

    Full Text Available at the amino acid level to the B. subtilis degS-degU genes showed 74% and 84% similarity, respectively. On a multicopy vector the B. brevis degS-degU genes were found to cause hypersecretion of several extracellular enzymes in a B. subtilis rec (-) strain...

  7. Sinusoidal synchronization of a Duffing oscillator with a chaotic pendulum

    Energy Technology Data Exchange (ETDEWEB)

    Min, Fuhong, E-mail: minfuhong@njnu.edu.cn [School of Electrical and Automation Engineering, Nanjing Normal University, Nanjing, Jiangsu 210042 (China); Luo, Albert C.J., E-mail: aluo@siue.edu [Department of Mechanical and Industrial Engineering, Southern Illinois University Edwardsville, Edwardsville, IL 62026-1805 (United States)

    2011-08-08

    In this Letter, analytical conditions for the sinusoidal synchronization of the pendulum and Duffing oscillator are presented. From the analytical conditions, the invariant domain of such sinusoidal synchronization is determined, and the control parameter map of the synchronicity is achieved. Under specific parameters, numerical illustrations of the partial and full sinusoidal synchronizations of the controlled Duffing oscillator with the pendulum are carried out for a better understanding of such synchronization under specific function constraints. The methodology presented in this Letter is applicable to synchronizations with any specific function constraints. -- Highlights: → Synchronization dynamics of two distinct dynamical systems. → Invariant domain of sinusoidal synchronization. → Partial and full sinusoidal synchronizations. → Analytical conditions for sinusoidal synchronization of the pendulum and Duffing oscillator. → Control parameter map for sinusoidal synchronization of the controlled Duffing oscillator with pendulum.

  8. Optimization of energy harvesting efficiency of an oscillating hydrofoil: Sinusoidal and Non-sinusoidal trajectories

    Science.gov (United States)

    Miller, Michael; Strom, Ben; Breuer, Kenneth; Mandre, Shreyas

    2014-11-01

    We determine the feasibility of applying optimization algorithms to an oscillating hydrofoil's motion trajectory to determine maximum efficiency of energy capture. Optimization is performed using the Nelder-Meade downhill simplex method. The objective function is the energy captured measured experimentally in run-time with an oscillating hydrofoil capable of measuring mechanical energy capture in a laboratory flume. For sinusoidal trajectories, optimization is performed over pitch and heave amplitudes as well as frequency; this system is shown to be capable of optimization in run-time. The optimum efficiency of 30% is found for a pitch amplitude of 70°, a heave amplitude of 0.8* chord and a dimensionless frequency of 0.13. To treat non-sinusoidal trajectories, we expand them in a truncated Fourier series and consider the coefficients of this series as variables for optimization. The sinusoidal case is simply an extreme case of such a truncated Fourier series, with only one term in the series retained. We present a systematic method for optimization over general non-sinusoidal trajectories by including more and more terms in the Fourier series.

  9. New Approaches for Channel Prediction Based on Sinusoidal Modeling

    Directory of Open Access Journals (Sweden)

    Ekman Torbjörn

    2007-01-01

    Full Text Available Long-range channel prediction is considered to be one of the most important enabling technologies to future wireless communication systems. The prediction of Rayleigh fading channels is studied in the frame of sinusoidal modeling in this paper. A stochastic sinusoidal model to represent a Rayleigh fading channel is proposed. Three different predictors based on the statistical sinusoidal model are proposed. These methods outperform the standard linear predictor (LP in Monte Carlo simulations, but underperform with real measurement data, probably due to nonstationary model parameters. To mitigate these modeling errors, a joint moving average and sinusoidal (JMAS prediction model and the associated joint least-squares (LS predictor are proposed. It combines the sinusoidal model with an LP to handle unmodeled dynamics in the signal. The joint LS predictor outperforms all the other sinusoidal LMMSE predictors in suburban environments, but still performs slightly worse than the standard LP in urban environments.

  10. Fisica degli atomi e dei nuclei

    CERN Document Server

    Bernardini, Carlo

    1965-01-01

    Evidenza della struttura atomica della materia ; le proprietà degli atomi e la meccanica atomica ; gli atomi e le radiazioni elettromagnetiche ; struttura microscopica dello stato gassoso ; struttura microscopica dello stato liquido ; struttura microscopica della stato solido ; proprietà elettriche e magnetiche delle sostanze ; proprietà dei nuclei degli atomi ; le particelle elementari.

  11. Compressed Domain Packet Loss Concealment of Sinusoidally Coded Speech

    DEFF Research Database (Denmark)

    Rødbro, Christoffer A.; Christensen, Mads Græsbøll; Andersen, Søren Vang

    2003-01-01

    We consider the problem of packet loss concealment for voice over IP (VoIP). The speech signal is compressed at the transmitter using a sinusoidal coding scheme working at 8 kbit/s. At the receiver, packet loss concealment is carried out working directly on the quantized sinusoidal parameters......, based on time-scaling of the packets surrounding the missing ones. Subjective listening tests show promising results indicating the potential of sinusoidal speech coding for VoIP....

  12. Amplitude Modulated Sinusoidal Signal Decomposition for Audio Coding

    DEFF Research Database (Denmark)

    Christensen, M. G.; Jacobson, A.; Andersen, S. V.

    2006-01-01

    In this paper, we present a decomposition for sinusoidal coding of audio, based on an amplitude modulation of sinusoids via a linear combination of arbitrary basis vectors. The proposed method, which incorporates a perceptual distortion measure, is based on a relaxation of a nonlinear least......-squares minimization. Rate-distortion curves and listening tests show that, compared to a constant-amplitude sinusoidal coder, the proposed decomposition offers perceptually significant improvements in critical transient signals....

  13. 3D angiography in the evaluation of intracranial aneurysms before and after treatment. Initial experience; L'angiografia 3D nella valutazione pre e post-trattamento degli aneurismi intracranici. Esperienza preliminare

    Energy Technology Data Exchange (ETDEWEB)

    Lauriola, Walter; Nardella, Michele; Strizzi, Vincenzo; Florio, Francesco [Casa Sollievo della Sofferenza, IRCCS San Giovanni Rotondo (Italy). Radiologia Interventistica; Cali, Alessandro; D' Angelo, Vincenzo [Casa Sollievo della Sofferenza, IRCCS San Giovanni Rotondo (Italy). Divisione di Neurochirugia

    2005-02-01

    optimisation of the technique in terms of anatomical detail and reconstruction time. [Italian] Scopo: Scopo del lavoro e' valutare i vantaggi dell'angiografia 3D nei confronti di quella 2D, nello studio degli aneurismi intracranici pre e post trattamento ed in particolare nella scelta e nella pianificazione del trattamento. Materiale e metodi: E' stato effettuato uno studio retrospettivo, pre e post-trattamento, di 30 aneurismi intracranici. la popolazione studio e' composta di 12 maschi e 18 femmine con range di eta' 35-77 anni, eta' media 58 anni. 18 aneurismi sono stati trattati chirurgicamente, 10 con tecnica endovascolare e 2 con trattamento combinato. E' stato eseguito il confronto tra reperti 2D e 3D DSA pre e post trattamento: le immagini angiografiche pre-trattamento sono state confrontate anche con i rispettivi reperti operatori. Sono stati presi in esame e confrontati i seguenti parametri: dimensioni della sacca e del colletto, individuazione di vasi coinvolti nell'aneurisma, valutazione del residuo post-trattamento. Risultati: L'esame 2D DSA ha consentito uno studio ottimale della sacca e del colletto rispettivamente nel 45% e 15%, sufficiente nel 10% e 35%, insoddisfacente nel 5% e 50% dei casi. Il corrispettivo esame 3D DSA ha permesso uno studio ottimale della sacca e del colletto nel 100% dei casi. La 3D DSA ha correttamente evidenziato 8 aneurismi (100%) con vaso coinvolto nella sacca e/o nel colletto; 4 (50%) di questi erano sfuggiti all'esame 2D, che ha inoltre erroneamente suggerito l'esistenza di vaso coinvolto in altri 2 casi (falsi +). L'esame angiografico 3D si e' mostrato superiore all'analogo 2D anche nella valutazione del residuo negli aneurismi trattati con clipping. Infine e' apparsa rilevante la capacita' della 3D DSA nel ridurre il numero di proiezioni radiografiche, la quantita' di mdc, il tempo ed i rischi connessi alla procedura, necessari per una valutazione

  14. Model selection and comparison for independents sinusoids

    DEFF Research Database (Denmark)

    Nielsen, Jesper Kjær; Christensen, Mads Græsbøll; Jensen, Søren Holdt

    2014-01-01

    this method by considering the problem in a full Bayesian framework instead of the approximate formulation, on which the asymptotic MAP criterion is based. This leads to a new model selection and comparison method, the lp-BIC, whose computational complexity is of the same order as the asymptotic MAP criterion......In the signal processing literature, many methods have been proposed for estimating the number of sinusoidal basis functions from a noisy data set. The most popular method is the asymptotic MAP criterion, which is sometimes also referred to as the BIC. In this paper, we extend and improve....... Through simulations, we demonstrate that the lp-BIC outperforms the asymptotic MAP criterion and other state of the art methods in terms of model selection, de-noising and prediction performance. The simulation code is available online....

  15. Stochastic analysis/synthesis using sinusoidal atoms

    DEFF Research Database (Denmark)

    Jensen, Kristoffer

    2008-01-01

    This work proposes a method for re-synthesizing music for use in perceptual experiments regarding structural changes and in music creation. Atoms are estimated from music audio, modelled in a stochastic model, and re-synthesized from the model pa- rameters. The atoms are found by splitting...... sinusoids into short segments, and modelled into amplitude and envelope shape, frequency, time and duration. A simple model for creating envelopes with percussive, sustained or crescendo shape is presented. Single variable and joint probability density functions are created from the atom parameters and used...... to re-create sounds with the same distribution of the atoms parameters. A novel method for visualization music, the musigram, permits a better understanding of the re- synthesized sounds....

  16. Sinusoidal Order Estimation Using Angles between Subspaces

    Directory of Open Access Journals (Sweden)

    Søren Holdt Jensen

    2009-01-01

    Full Text Available We consider the problem of determining the order of a parametric model from a noisy signal based on the geometry of the space. More specifically, we do this using the nontrivial angles between the candidate signal subspace model and the noise subspace. The proposed principle is closely related to the subspace orthogonality property known from the MUSIC algorithm, and we study its properties and compare it to other related measures. For the problem of estimating the number of complex sinusoids in white noise, a computationally efficient implementation exists, and this problem is therefore considered in detail. In computer simulations, we compare the proposed method to various well-known methods for order estimation. These show that the proposed method outperforms the other previously published subspace methods and that it is more robust to the noise being colored than the previously published methods.

  17. A generalized sinusoidal model and its applications

    Institute of Scientific and Technical Information of China (English)

    KU Shao-ping; LI Ning

    2009-01-01

    A physical model of sinusoidal function was established. It is generalized that the force is directly proportional to a power function of the distance in a classical spring-oscillator system. The differential equation of the generalized model was given. Simulations were conducted with different power values. The results show that the solution of the generalized equation is a periodic function. The expressions of the amplitude and the period (frequency) of the generalized equation were derived by the physical method. All the simulation results coincide with the calculation results of the derived expressions. A special function also was deduced and proven to be convergent in the theoretical analysis. The limit value of the special function also was derived. The generalized model can be used in solving a type of differential equation and to generate periodic waveforms.

  18. Electrochemical investigation of crack initiation during corrosion fatigue of stainless steels in the passive state. Elektrochemische Untersuchung der Rissbildung bei Schwingungsrisskorrosion im stabil-passiven Werkstoffzustand

    Energy Technology Data Exchange (ETDEWEB)

    Spaehn, R. (Technische Hochschule Darmstadt (Germany, F.R.))

    1991-03-01

    The corrosion fatigue behaviour of three stainless steels - ferritic (12% Cr), austenitic (type 316 Ti) and austenitic-ferritic (type 31803; Duplex stainless steel) - was studied under rotating bending moments in aqueous sulphuric acid of 30deg C. An instrumental set-up for recording the transient currents of specimens during potentiostatically controlled corrosion fatigue is described. Based on this transient current signal technique, three stages on the corrosion fatigue process can be discerned. In the incubation period, small stochastic current transients are caused by the response of the passive layer to alternating stresses and environmental conditions. The appearance of sinusoidal current signals indicates crack initiation whereas the phase angle between a fixed marker - i.e. a light barrier signal -, and the anodic amplitude represents the site of initiating cracks. Finally, the crack growth period is characterized by an increasing cell current and steadily growing sinusoidal current signals caused by the interplay of microplastic and repassivation processes at the crack tip. (orig.).

  19. Variable Dimension Trellis-Coded Quantization of Sinusoidal Parameters

    DEFF Research Database (Denmark)

    Larsen, Morten Holm; Christensen, Mads G.; Jensen, Søren Holdt

    2008-01-01

    In this letter, we propose joint quantization of the parameters of a set of sinusoids based on the theory of trellis-coded quantization. A particular advantage of this approach is that it allows for joint quantization of a variable number of sinusoids, which is particularly relevant in variable...

  20. Analytical analysis of the Pennes bioheat transfer equation with sinusoidal heat flux condition on skin surface.

    Science.gov (United States)

    Shih, Tzu-Ching; Yuan, Ping; Lin, Win-Li; Kou, Hong-Sen

    2007-11-01

    This study focuses on the effect of the temperature response of a semi-infinite biological tissue due to a sinusoidal heat flux at the skin. The Pennes bioheat transfer equation such as rho(t)c(t)( partial differentialT/ partial differentialt)+W(b)c(b)(T-T(a))=k partial differential(2)T/ partial differentialx(2) with the oscillatory heat flux boundary condition such as q(0,t)=q(0)e(iomegat) was investigated. By using the Laplace transform, the analytical solution of the Pennes bioheat transfer equation with surface sinusoidal heating condition is found. This analytical expression is suitable for describing the transient temperature response of tissue for the whole time domain from the starting periodic oscillation to the final steady periodic oscillation. The results show that the temperature oscillation due to the sinusoidal heating on the skin surface is unstable in the initial period. Further, it is unavailable to predict the blood perfusion rate via the phase shifting between the surface heat flux and the surface temperature. Moreover, the lower frequency of sinusoidal heat flux on the skin surface induces a more sensitive phase shift response to the blood perfusion rate change, but extends the beginning time of sampling because of the avoidance of the unavailable first cyclic oscillation.

  1. Significance of power average of sinusoidal and non-sinusoidal periodic excitations in nonlinear non-autonomous system

    Indian Academy of Sciences (India)

    VENKATESH P R; VENKATESAN A

    2016-07-01

    Additional sinusoidal and different non-sinusoidal periodic perturbations applied to the periodically forced nonlinear oscillators decide the maintainance or inhibitance of chaos. It is observed that the weak amplitude of the sinusoidal force without phase is sufficient to inhibit chaos rather than the other non-sinusoidal forces and sinusoidal force with phase. Apart from sinusoidal force without phase, i.e., from various non-sinusoidal forces and sinusoidal force with phase, square force seems to be an effective weak perturbation to suppress chaos. The effectiveness of weak perturbation for suppressing chaos is understood with the total power average of the external forces applied to the system. In any chaotic system, the total power average of the external forces isconstant and is different for different nonlinear systems. This total power average decides the nature of the force to suppress chaos in the sense of weak perturbation. This has been a universal phenomenon for all the chaoticnon-autonomous systems. The results are confirmed by Melnikov method and numerical analysis. With the help of the total power average technique, one can say whether the chaos in that nonlinear system is to be supppressed or not.

  2. Optical antennas with sinusoidal modulation in width.

    Science.gov (United States)

    Dikken, Dirk Jan; Segerink, Frans B; Korterik, Jeroen P; Pfaff, Stefan S; Prangsma, Jord C; Herek, Jennifer L

    2016-08-08

    Small metal structures sustaining plasmon resonances in the optical regime are of great interest due to their large scattering cross sections and ability to concentrate light to subwavelength volumes. In this paper, we study the dipolar plasmon resonances of optical antennas with a constant volume and a sinusoidal modulation in width. We experimentally show that by changing the phase of the width-modulation, with a small 10 nm modulation amplitude, the resonance shifts over 160 nm. Using simulations we show how this simple design can create resonance shifts greater than 600 nm. The versatility of this design is further shown by creating asymmetric structures with two different modulation amplitudes, which we experimentally and numerically show to give rise to two resonances. Our results on both the symmetric and asymmetric antennas show the capability to control the localization of the fields outside the antenna, while still maintaining the freedom to change the antenna resonance wavelength. The antenna design we tested combines a large spectral tunability with a small footprint: all the antenna dimensions are factor 7 to 13 smaller than the wavelength, and hold potential as a design element in meta-surfaces for beam shaping.

  3. Pressure profile in liver sinusoids. A model of localization of sinusoidal resistance in the normal and cirrhotic liver

    DEFF Research Database (Denmark)

    Henriksen, J H; Lassen, N A

    1988-01-01

    A model of pressure profile along the sinusoids in the liver is presented. The major prerequisite is a converging sinusoidal flow pattern through a network of tubes with almost equal diameter. In this case the main hemodynamic resistance is located downstream at the outlet. Different geometric...... configurations (sphere, cylinder, and sections of these) are considered, and it is concluded that the precise shape of the microcirculatory unit is not crucial. The applicability in cirrhosis is considered in relation to a decreased diameter and number of the sinusoids in this condition. Estimated pressure...... profiles along the sinusoids indicate a steep downstream pressure fall in cirrhosis, implying that the spatial average of sinusoidal pressure is close to that of the inlet, i.e. portal pressure. Another prediction is an increased blood flow rate (flow rate per vessel) in the region near the outlet...

  4. Pressure profile in liver sinusoids. A model of localization of sinusoidal resistance in the normal and cirrhotic liver

    DEFF Research Database (Denmark)

    Henriksen, Jens Henrik Sahl; Lassen, N A

    1988-01-01

    profiles along the sinusoids indicate a steep downstream pressure fall in cirrhosis, implying that the spatial average of sinusoidal pressure is close to that of the inlet, i.e. portal pressure. Another prediction is an increased blood flow rate (flow rate per vessel) in the region near the outlet......A model of pressure profile along the sinusoids in the liver is presented. The major prerequisite is a converging sinusoidal flow pattern through a network of tubes with almost equal diameter. In this case the main hemodynamic resistance is located downstream at the outlet. Different geometric...... configurations (sphere, cylinder, and sections of these) are considered, and it is concluded that the precise shape of the microcirculatory unit is not crucial. The applicability in cirrhosis is considered in relation to a decreased diameter and number of the sinusoids in this condition. Estimated pressure...

  5. Sinusoidal Analysis-Synthesis of Audio Using Perceptual Criteria

    Directory of Open Access Journals (Sweden)

    Ted Painter

    2003-01-01

    Full Text Available This paper presents a new method for the selection of sinusoidal components for use in compact representations of narrowband audio. The method consists of ranking and selecting the most perceptually relevant sinusoids. The idea behind the method is to maximize the matching between the auditory excitation pattern associated with the original signal and the corresponding auditory excitation pattern associated with the modeled signal that is being represented by a small set of sinusoidal parameters. The proposed component-selection methodology is shown to outperform the maximum signal-to-mask ratio selection strategy in terms of subjective quality.

  6. Improved Multiple Descriptions Sinusoidal Coder Adaptive to Packet Loss Rate

    Institute of Scientific and Technical Information of China (English)

    LANG Yue; WANG Jing; ZHAO Sheng-hui; KUANG Jing-ming

    2008-01-01

    To make the multiple descriptions codec adaptive to the packet loss rate, which can minimize the final distortion, a novel adaptive multiple descriptions sinusoidal coder (AMDSC) is proposed, which is based on a sinusoidal model and a noise model. Firstly, the sinusoidal parameters are extracted in the sinusoidal model, and ordered in a decrease manner. Odd indexed and even indexed parameters are divided into two descriptions. Secondly, the output vector from the noise model is split vector quantized. And the two sub-vectors are placed into two descriptions too. Finally, the number of the extracted parameters and the redundancy between the two descriptions are adjusted according to the packet loss rate of the network. Analytical and experimental results show that the proposed AMDSC outperforms existing MD speech coders by taking network loss characteristics into account. Therefore, it is very suitable for unreliable channels.

  7. Propiedades de transporte de una superred de grafeno tipo sinusoidal

    National Research Council Canada - National Science Library

    J. A. Briones-Torres; I. Rodríguez-Vargas

    2015-01-01

    ... a través de superredes en grafeno. Consideramos una superred con potencial sinusoidal o polaridad invertida, para ello consideramos dos maneras de crearla, una por medio de sustratos mixtos junto...

  8. Semidefinite Programming for Approximate Maximum Likelihood Sinusoidal Parameter Estimation

    OpenAIRE

    2009-01-01

    We study the convex optimization approach for parameter estimation of several sinusoidal models, namely, single complex/real tone, multiple complex sinusoids, and single two-dimensional complex tone, in the presence of additive Gaussian noise. The major difficulty for optimally determining the parameters is that the corresponding maximum likelihood (ML) estimators involve finding the global minimum or maximum of multimodal cost functions because the frequencies are nonlinear in the observed s...

  9. La formazione iniziale degli insegnanti in Italia

    Directory of Open Access Journals (Sweden)

    Carlo Cappa

    2013-07-01

    Full Text Available L’articolo è diviso in tre parti. La prima presenta gli elementi storici e di sfondo che occorre tenere presenti per comprendere l’evoluzione della formazione iniziale degli insegnanti verso gli attuali modelli, che pur essendo oggi tutti gestiti dalle università conservano una sensibile diversità a seconda che si tratti di formare maestri per la scuola dell’infanzia e primaria oppure professori di scuola secondaria di primo e secondo grado. La seconda parte analizza il passaggio, maturato tra la fine del secolo scorso e l’inizio del XXI secolo, della formazione dei maestri dalla scuola secondaria (Istituto magistrale all’università (Corso di laurea in Scienze della formazione primaria, e l’istituzione delle Scuole di Specializzazione per l’Insegnamento Secondario (SSIS fino alla soppressione di queste ultime, avvenuta nel 2009. La terza parte presenta il quadro attuale della formazione iniziale dei docenti in Italia con riguardo soprattutto agli insegnanti della scuola secondaria, per i quali – a differenza che per i maestri - sono intervenute dal 2010 importanti innovazioni legislative. Le SSIS sono state infatti sostituite con il Tirocinio Formativo Attivo (TFA, attualmente in fase di attuazione da parte delle università. Nella parte finale dell’articolo si traccia un primo bilancio dell’esperienza del TFA e si indicano alcuni problemi aperti. Il focus rimane sostanzialmente sulla formazione iniziale, in quanto in Italia la formazione in servizio, che pure non è del tutto assente, non è mai stata oggetto di una normativa né di una azione organica, ma avviene, quando avviene, sulla base di iniziative di specifici gruppi o associazioni.The article is organised in three parts. The first one illustrates the historical features and the institutional and political background that have to be taken into account in order to understand how initial teacher education and training has developed in Italy. Presently, all teacher

  10. Compensated-power differential calorimeter -196 deg. C/400 deg. C; Calorimetre differentiel a puissance compensee -196 deg. C/400 deg. C

    Energy Technology Data Exchange (ETDEWEB)

    Bonjour, E.; Pierre, J.; Agagliate, S.; Bertrand, P.; Faivre, J.; Lagnier, R. [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires, Section physico-chimie et basses temperatures

    1967-06-01

    A differential calorimetric device of original design is described. Its allows direct measurements of thermal effects (adsorption or release) during a linear rise of temperature. The self compensated power method which is applied by means of a very sensitive control system, gives a direct value of the different heat capacity between the sample and a dummy of it. The detection threshold is about {+-} 100 micro-watts to {+-} 250 micro-watts. Applications: - Generally measurements of enthalpy changes of massive or powdered samples. - Measurement of Wigner energy after low temperature irradiation (77 deg. K). - Measurements of energy release in low temperature (77 deg. K) cold worked metals. (authors) [French] On decrit un dispositif de calorimetrie differentielle, de conception originale, qui permet de mesurer directement des effets thermiques en absorption ou en degagement de chaleur, au cours d'une montee en temperature lineaire. La methode de compensation automatique de puissance qui est mise en oeuvre au moyen de cha es d'asservissement tres sensibles, conduit a une determination directe de la capacite calorifique differencielle entre l'echantillon et sa reference. Le seuil de detection est de l'ordre de {+-} 100 a {+-} 250 microwatts. Applications: - D'une facon generale, mesure des variations enthalpiques, sur echantillons massifs ou en poudre. - Mesure de l'energie Wigner apres irradiation a basse temperature (77 deg. K). - Mesure de l'energie restauree apres deformation des metaux a basse temperature (77 deg. K). (auteurs)

  11. Testimonianze di vittime degli anni di piombo

    DEFF Research Database (Denmark)

    Cecchini, Leonardo

    Testimonianze di vittime degli anni di piombo In un articolo pubblicato nel 2008 sulla webzine Nazione indiana Christian Raimo criticava quello che poi Giovanni De Luna qualche anno dopo nel suo libro La Repubblica del dolore (2011) ha chiamato “paradigma vittimario”; cioè la presenza predominante...

  12. Comparison of PCBBs and CTs irradiated at 250 deg. C, 300 deg. C, and 350 deg. C

    Energy Technology Data Exchange (ETDEWEB)

    Rensman, J.; Nolles, H.N. [ECN-Energy Research Foundation, Research Unit NRG, Westerduinweg, Petten (Netherlands); Lucon, E. [SCK-CEN, Institute of Nuclear Material Science, Boeretang, Mol (Belgium); Spatig, P. [EPFL-CRDP, Centre de Recherches en Physique des Plasmas, Association Euratom-Confederation Suisse, CH Villigen PSI (Switzerland)

    2007-07-01

    Full text of publication follows: The fracture toughness of irradiated Eurofer steel is difficult to characterise. Several limitations are identified in this paper with respect to the conventional treatment of fracture data of BCC steels in the transition region. It is uncertain that the RPV Master Curve is applicable to unirradiated Eurofer, and low temperature irradiation adds more to this uncertainty. The lack of strain hardening and the dose variation within each batch are two complicating factors. An irradiation has been carried out in the BFR up to a nominal dose of 2.5 dpa at 250 deg. C, 300 deg. C, and 350 deg. C in sodium. Twelve small size pre-cracked bend specimens and eight mini-CT specimens have been irradiated in each temperature section. We analyse the effect of constraint and censoring limit, and the specimen geometry and loading configuration. The fracture data are treated in several ways that are proposed in open literature to investigate the effect of irradiation on a reference temperature like the ASTM E1921 T0. In addition, the relation between the tensile hardening, which is presented in a companion paper, and the shift calculated with the various methods is studied. (authors)

  13. Bacillus subtilis Two-Component System Sensory Kinase DegS Is Regulated by Serine Phosphorylation in Its Input Domain

    Science.gov (United States)

    Jers, Carsten; Kobir, Ahasanul; Søndergaard, Elsebeth Oline; Jensen, Peter Ruhdal; Mijakovic, Ivan

    2011-01-01

    Bacillus subtilis two-component system DegS/U is well known for the complexity of its regulation. The cytosolic sensory kinase DegS does not receive a single predominant input signal like most two-component kinases, instead it integrates a wide array of metabolic inputs that modulate its activity. The phosphorylation state of the response regulator DegU also does not confer a straightforward “on/off” response; it is fine-tuned and at different levels triggers different sub-regulons. Here we describe serine phosphorylation of the DegS sensing domain, which stimulates its kinase activity. We demonstrate that DegS phosphorylation can be carried out by at least two B. subtilis Hanks-type kinases in vitro, and this stimulates the phosphate transfer towards DegU. The consequences of this process were studied in vivo, using phosphomimetic (Ser76Asp) and non-phosphorylatable (Ser76Ala) mutants of DegS. In a number of physiological assays focused on different processes regulated by DegU, DegS S76D phosphomimetic mutant behaved like a strain with intermediate levels of DegU phosphorylation, whereas DegS S76A behaved like a strain with lower levels of DegU phophorylation. These findings suggest a link between DegS phosphorylation at serine 76 and the level of DegU phosphorylation, establishing this post-translational modification as an additional trigger for this two-component system. PMID:21304896

  14. Bacillus subtilis two-component system sensory kinase DegS is regulated by serine phosphorylation in its input domain.

    Directory of Open Access Journals (Sweden)

    Carsten Jers

    Full Text Available Bacillus subtilis two-component system DegS/U is well known for the complexity of its regulation. The cytosolic sensory kinase DegS does not receive a single predominant input signal like most two-component kinases, instead it integrates a wide array of metabolic inputs that modulate its activity. The phosphorylation state of the response regulator DegU also does not confer a straightforward "on/off" response; it is fine-tuned and at different levels triggers different sub-regulons. Here we describe serine phosphorylation of the DegS sensing domain, which stimulates its kinase activity. We demonstrate that DegS phosphorylation can be carried out by at least two B. subtilis Hanks-type kinases in vitro, and this stimulates the phosphate transfer towards DegU. The consequences of this process were studied in vivo, using phosphomimetic (Ser76Asp and non-phosphorylatable (Ser76Ala mutants of DegS. In a number of physiological assays focused on different processes regulated by DegU, DegS S76D phosphomimetic mutant behaved like a strain with intermediate levels of DegU phosphorylation, whereas DegS S76A behaved like a strain with lower levels of DegU phophorylation. These findings suggest a link between DegS phosphorylation at serine 76 and the level of DegU phosphorylation, establishing this post-translational modification as an additional trigger for this two-component system.

  15. Half-Tone Video Images Of Drifting Sinusoidal Gratings

    Science.gov (United States)

    Mulligan, Jeffrey B.; Stone, Leland S.

    1991-01-01

    Digital technique for generation of slowly moving video image of sinusoidal grating avoids difficulty of transferring full image data from disk storage to image memory at conventional frame rates. Depends partly on trigonometric identity by which moving sinusoidal grating decomposed into two stationary patterns spatially and temporally modulated in quadrature. Makes motion appear smooth, even at speeds much less than one-tenth picture element per frame period. Applicable to digital video system in which image memory consists of at least 2 bits per picture element, and final brightness of picture element determined by contents of "lookup-table" memory programmed anew each frame period and indexed by coordinates of each picture element.

  16. Perambatan Gelombang Optik pada Grating Sinusoidal dengan Chirp dan Taper

    Directory of Open Access Journals (Sweden)

    Isnani Darti

    2009-11-01

    menggunakan MIL, dipelajari perubahan respon optik pada grating sinusoidal akibat variasi amplitudo modulasi indeks (taper dan variasi frekuensi spasial grating (chirp. Hasil simulasi menunjukkan bahwa taper menyebabkan adanya fenomena penghilangan side-lobe pada spektrum transmitansi. Adanya chirp menyebabkan penghalusan side-lobe pada spektrum transmitansi dengan semakin besar parameter chirp menyebabkan peningkatan transmitansi di sekitar pusat band-gap dari grating homogen. Selain implementasi integrasi numerik (Runge-Kutta, MIL merupakan metode eksak sehingga dapat digunakan untuk mengevaluasi validitas metode yang sering digunakan yaitu Persamaan Moda Tergandeng (PMT. Dari hasil perbandingan dapat disimpulkan bahwa secara umum PMT kurang akurat dalam menganalisis struktur grating sinusoidal baik homogen maupun tak-homogen.

  17. Estimation of amplitude and standard deviation of noisy sinusoidal signals

    Science.gov (United States)

    Juarez-Salazar, Rigoberto; Diaz-Ramirez, Victor H.

    2017-01-01

    A simple method to estimate the amplitude and standard deviation of sinusoidal signals corrupted with additive Gaussian noise is proposed. For this, a two-parameter model is developed by sorting the samples of the signal. This reduced parametric model allows robust parameter estimation, even if the phase function of the sinusoid is nonlinear, discontinuous, and unknown. The functionality and performance of the proposed method are analyzed by several computer simulations; the used GNU Octave program is provided. The proposed method can be useful for unbiased envelope estimation in fringe pattern normalization among other potential applications.

  18. Long Term Maintenance of a Microfluidic 3-D Human Liver Sinusoid

    OpenAIRE

    Prodanov, Ljupcho; Jindal, Rohit; Bale, Shyam Sundhar; Hegde, Manjunath; McCarty, William J.; Golberg, Inna; Bhushan, Abhinav; Yarmush, Martin L.; Usta, O. Berk

    2015-01-01

    The development of long-term human organotypic liver-on-a-chip models for successful prediction of toxic response is one of the most important and urgent goals of the NIH/DARPA’s initiative to replicate and replace chronic and acute drug testing in animals. For this purpose we developed a microfluidic chip that consists of two microfluidic chambers separated by a porous membrane. The aim of this communication is to demonstrate the recapitulation of a liver sinusoid-on-a-chip using human cells...

  19. Enhanced nonlinear spectral compression in fiber by external sinusoidal phase modulation

    Science.gov (United States)

    Boscolo, S.; Mouradian, L. Kh; Finot, C.

    2016-10-01

    We propose a new, simple approach to enhance the spectral compression process arising from nonlinear pulse propagation in an optical fiber. We numerically show that an additional sinusoidal temporal phase modulation of the pulse enables efficient reduction of the intensity level of the side lobes in the spectrum that are produced by the mismatch between the initial linear negative chirp of the pulse and the self-phase modulation-induced nonlinear positive chirp. Remarkable increase of both the extent of spectrum narrowing and the quality of the compressed spectrum is afforded by the proposed approach across a wide range of experimentally accessible parameters.

  20. Ageing monitoring in IGBT module under sinusoidal loading

    DEFF Research Database (Denmark)

    Ghimire, Pramod; Pedersen, Kristian Bonderup; Rannestad, Bjørn

    2015-01-01

    This paper presents monitoring of ageing in high power insulated gate bipolar transistor (IGBT) modules subjected to sinusoidal loading at nominal power level. On-state voltage for IGBT, diode, and rise in interconnection resistance are used as ageing parameters. These are measured in three diffe...

  1. Using piecewise sinusoidal basis functions to blanket multiple wire segments

    CSIR Research Space (South Africa)

    Lysko, AA

    2009-06-01

    Full Text Available This paper discusses application of the piecewise sinusoidal (PWS) basis function (BF) over a chain of several wire segments, for example as a multiple domain basis function. The usage of PWS BF is compared to results based on the piecewise linear...

  2. Synthesis of a Novel Low-Component Programmable Sinusoidal Oscillator

    Directory of Open Access Journals (Sweden)

    Muhammad Taher Abuelma'atti

    2003-01-01

    Full Text Available A novel circuit is presented for realizing a sinusoidal oscillator. The proposed circuit, developed through a true synthesis approach, uses one current-feedback operational amplifier (CFOA, one operational transconductance amplifier (OTA, three grounded capacitors and one floating resistor. The proposed circuit enjoys several attractive features. Practical results, in excellent agreement with the presented theory, are included.

  3. Sound waves in two-dimensional ducts with sinusoidal walls

    Science.gov (United States)

    Nayfeh, A. H.

    1974-01-01

    The method of multiple scales is used to analyze the wave propagation in two-dimensional hard-walled ducts with sinusoidal walls. For traveling waves, resonance occurs whenever the wall wavenumber is equal to the difference of the wavenumbers of any two duct acoustic modes. The results show that neither of these resonating modes could occur without strongly generating the other.

  4. Using Antenna Arrays to Motivate the Study of Sinusoids

    Science.gov (United States)

    Becker, J. P.

    2010-01-01

    Educational activities involving antenna arrays to motivate the study of sinusoids are described. Specifically, using fundamental concepts related to phase and simple geometric arguments, students are asked to predict the location of interference nulls in the radiation pattern of two-element phased array antennas. The location of the radiation…

  5. Non-Sinusoidal PWM Method for Cascaded Multilevel Inverter

    Directory of Open Access Journals (Sweden)

    Abdul Halim M. Yatim

    2012-08-01

    Full Text Available This paper presents a new switching method for Cascaded Multilevel Inverter (CMI.  The new method uses multiple non-sinusoidal signals as the modulating signal.  The main advantage of using non-sinusoidal modulating signal is that it provides higher fundamental component but at the cost of having a numbers of low-order harmonics in its unfiltered output voltage; naturally contributed by the non-sinusoidal modulating signal. In this paper, the Trapezoidal waveform is employed as the non-sinusoidal modulating signal for the CMI.  Its harmonics profile of different slope angles is analysed.  From the analysis, it was found that the trapezoidal with the slope angle of 36o eliminates the third and fifth harmonics yet yields a high fundamental magnitude.  To verify, a single-phase CMI prototype is constructed and an ALTERA FPGA is deployed to implement the proposed method’s algorithm.  From the results, it was shown that analysis is validated

  6. Using Antenna Arrays to Motivate the Study of Sinusoids

    Science.gov (United States)

    Becker, J. P.

    2010-01-01

    Educational activities involving antenna arrays to motivate the study of sinusoids are described. Specifically, using fundamental concepts related to phase and simple geometric arguments, students are asked to predict the location of interference nulls in the radiation pattern of two-element phased array antennas. The location of the radiation…

  7. Global map of lithosphere thermal thickness on a 1 deg x 1 deg grid - digitally available

    DEFF Research Database (Denmark)

    Artemieva, Irina

    2014-01-01

    than 250 km) lithosphere is restrictedsolely to young Archean terranes (3.0–2.6 Ga), while in old Archean cratons (3.6–3.0 Ga) lithospheric roots donot extend deeper than 200–220 km.The TC1 model is presented by a set of maps, which show significant thermal heterogeneity within continentalupper mantle......This presentation reports a 1 deg 1 deg global thermal model for the continental lithosphere (TC1). The modelis digitally available from the author’s web-site: www.lithosphere.info.Geotherms for continental terranes of different ages (early Archean to present) are constrained by reliabledata...

  8. THE NO SINUSOIDAL VOLTAGES UNDER THE SINUSOIDAL CURRENT AT THE ENTRY OF THE OPEN–ENDED LINE WITH REAL LOSS

    Directory of Open Access Journals (Sweden)

    Patsiuk V.I.

    2008-12-01

    Full Text Available he classical problems of the theoretical electrical engineering, such as open-ended (or short-circuited line energization on alternating voltage (or current, are solved by means of Fourier series method. The conditions of creation of no sinusoidal steady-state regimes in the lines with nonzero loss are discovered.

  9. Bacillus subtilis Two-Component System Sensory Kinase DegS Is Regulated by Serine Phosphorylation in Its Input Domain

    DEFF Research Database (Denmark)

    Jers, Carsten; Kobir, Ahasanul; Søndergaard, Elsebeth Oline;

    2011-01-01

    Bacillus subtilis two-component system DegS/U is well known for the complexity of its regulation. The cytosolic sensory kinase DegS does not receive a single predominant input signal like most two-component kinases, instead it integrates a wide array of metabolic inputs that modulate its activity...

  10. Angiopatia diabetica e amputazione degli arti inferiori: valutazioni preliminari degli episodi di ricovero ripetuti

    Directory of Open Access Journals (Sweden)

    P. Trerotoli

    2003-05-01

    Full Text Available

    Obiettivi: l’obiettivo principale dello studio è stata la valutazione dei ricoveri ripetuti nei soggetti con vasculopatia diabetica, rispetto ai soggetti con vasculopatia non diabetica.

    Materiali e Metodi: sono state selezionate le SDO del triennio 1998-2000 contenenti, in uno dei campi di diagnosi, i codici di diabete mellito, con e senza complicanze (codici ICD9 ed ICD9CM, 250.—, vasculopatia periferica (440.2 e 440.8, ulcera periferica (707.1, 707.8, 707.9, gangrena (785.4. Le SDO con diagnosi di vasculopatia diabetica sono state considerate come angiopatie diabetiche (AD; le altre sono state attribuite agli angiopatici non diabetici (AND. Le SDO con diabete non complicato e arteriopatia periferica sono state eliminate. L’intervento di amputazione è stato individuato dalla presenza del codice ICD9CM di procedura 84.—. La ripetitività degli episodi è stata valutata usando il codice fiscale come identificativo del paziente. Risultati: sono state rilevate 5814 dimissioni di AD e 9010 di AND. Le amputazioni sono state 285 (4,90% negli AD e 485 (5,38% negli AND. I ricoveri ripetuti sono stati 13 negli AD e 12 negli AND. Le amputazioni sono state osservate verso il 4°-5° episodio di ricovero negli AD, mentre già dal 2° episodio negli AND. Le ulcere erano presenti nel 36,05% (il 36,5% nel primo episodio di ricovero, che resta costante negli episodi successivi degli AND e nel 10,97% degli AD (9,84% nel primo episodio, con un incremento fino al 20% del 5° episodio. Un episodio in day-hospital (DH si osserva nel 12,32% degli AD, contro il 4,20% degli AND.

    Conclusioni: l’accesso degli AD all’assistenza intraospedaliera avviene più frequentemente in DH, i passi successivi sono caratterizzati dalla comparsa dell’ulcera o gangrena e infine dall’amputazione. Nel gruppo degli AD è stato osservato un eccesso di ospedalizzazione, probabilmente per ripetitività del

  11. Propulsion by sinusoidal locomotion: A motion inspired by Caenorhabditis elegans

    Science.gov (United States)

    Ulrich, Xialing

    Sinusoidal locomotion is commonly seen in snakes, fish, nematodes, or even the wings of some birds and insects. This doctoral thesis presents the study of sinusoidal locomotion of the nematode C. elegans in experiments and the application of the state-space airloads theory to the theoretical forces of sinusoidal motion. An original MATLAB program has been developed to analyze the video records of C. elegans' movement in different fluids, including Newtonian and non-Newtonian fluids. The experimental and numerical studies of swimming C. elegans has revealed three conclusions. First, though the amplitude and wavelength are varying with time, the motion of swimming C. elegans can still be viewed as sinusoidal locomotion with slips. The average normalized wavelength is a conserved character of the locomotion for both Newtonian and non-Newtonian fluids. Second, fluid viscosity affects the frequency but not the moving speed of C. elegans, while fluid elasticity affects the moving speed but not the frequency. Third, by the resistive force theory, for more elastic fluids the ratio of resistive coefficients becomes smaller. Inspired by the motion of C. elegans and other animals performing sinusoidal motion, we investigated the sinusoidal motion of a thin flexible wing in theory. Given the equation of the motion, we have derived the closed forms of propulsive force, lift and other generalized forces applying on the wing. We also calculated the power required to perform the motion, the power lost due to the shed vortices and the propulsive efficiency. These forces and powers are given as functions of reduced frequency k, dimensionless wavelength z, dimensionless amplitude A/b, and time. Our results show that a positive, time-averaged propulsive force is produced for all k>k0=pi/ z. At k=k0, which implies the moment when the moving speed of the wing is the same as the wave speed of its undulation, the motion reaches a steady state with all forces being zero. If there were no

  12. The sinusoidal lining cells in "normal" human liver. A scanning electron microscopic investigation

    DEFF Research Database (Denmark)

    Horn, T; Henriksen, Jens Henrik Sahl; Christoffersen, P

    1986-01-01

    The scanning electron microscopic was used to study the fenestrations of human liver sinusoids. Thirteen biopsies, where light microscopy and transmission electron microscopy revealed normal sinusoidal architecture, were investigated. The number of fenestrae was calculated in acinar zone 3...

  13. Multipath time delay estimation of underwater acoustic sinusoidal signals

    Institute of Scientific and Technical Information of China (English)

    TONG Feng; XU Xiaomei; FANG Shiliang

    2009-01-01

    To overcome the performance limitation of multipath time-delay estimation posed by underwater acoustic sinusoidal signals, an approach incorporating the frequency-domain weighting of the highly oscillatory Nonlinear Least Squares (NLS) cost function with the evolutionary optimization was proposed to facilitate the accurate estimation of the multipath timedelay of sinusoidal signals. In the described method, the number of the effective multipath signals, which is included into the parameter model as well as the multipath time-delay and amplitude factor, can be estimated simultaneously thus avoiding the requirement of additional computation. The experimental results performed with numerical simulation and sea-trial data are provided, demonstrating the effectiveness and precision enhancement of the proposed algorithm.

  14. Electric stimulation with sinusoids and white noise for neural prostheses

    Directory of Open Access Journals (Sweden)

    Daniel K Freeman

    2010-02-01

    Full Text Available We are investigating the use of novel stimulus waveforms in neural prostheses to determine whether they can provide more precise control over the temporal and spatial pattern of elicited activity as compared to conventional pulsatile stimulation. To study this, we measured the response of retinal ganglion cells to both sinusoidal and white noise waveforms. The use of cell-attached and whole cell patch clamp recordings allowed the responses to be observed without significant obstruction from the stimulus artifact. Electric stimulation with sinusoids elicited robust responses. White noise analysis was used to derive the linear kernel for the ganglion cell’s spiking response as well as for the underlying excitatory currents. These results suggest that in response to electric stimulation, presynaptic retinal neurons exhibit bandpass filtering characteristics with peak response that occur 25ms after onset. The experimental approach demonstrated here may be useful for studying the temporal response properties of other neurons in the CNS.

  15. Semidefinite Programming for Approximate Maximum Likelihood Sinusoidal Parameter Estimation

    Directory of Open Access Journals (Sweden)

    Kenneth W. K. Lui

    2009-01-01

    Full Text Available We study the convex optimization approach for parameter estimation of several sinusoidal models, namely, single complex/real tone, multiple complex sinusoids, and single two-dimensional complex tone, in the presence of additive Gaussian noise. The major difficulty for optimally determining the parameters is that the corresponding maximum likelihood (ML estimators involve finding the global minimum or maximum of multimodal cost functions because the frequencies are nonlinear in the observed signals. By relaxing the nonconvex ML formulations using semidefinite programs, high-fidelity approximate solutions are obtained in a globally optimum fashion. Computer simulations are included to contrast the estimation performance of the proposed semi-definite relaxation methods with the iterative quadratic maximum likelihood technique as well as Cramér-Rao lower bound.

  16. Semidefinite Programming for Approximate Maximum Likelihood Sinusoidal Parameter Estimation

    Science.gov (United States)

    Lui, Kenneth W. K.; So, H. C.

    2009-12-01

    We study the convex optimization approach for parameter estimation of several sinusoidal models, namely, single complex/real tone, multiple complex sinusoids, and single two-dimensional complex tone, in the presence of additive Gaussian noise. The major difficulty for optimally determining the parameters is that the corresponding maximum likelihood (ML) estimators involve finding the global minimum or maximum of multimodal cost functions because the frequencies are nonlinear in the observed signals. By relaxing the nonconvex ML formulations using semidefinite programs, high-fidelity approximate solutions are obtained in a globally optimum fashion. Computer simulations are included to contrast the estimation performance of the proposed semi-definite relaxation methods with the iterative quadratic maximum likelihood technique as well as Cramér-Rao lower bound.

  17. Electronic Bands Behaviour at Sinusoidal Potential Presence of Incommensurate Crystals

    OpenAIRE

    Vlokh R.; Vlokh O.; Lukiyanets B.

    2004-01-01

    On the basis of solving the Schrodinger and Mathieu equations, for the case of crystal field perturbed by one-dimensional sinusoidal potential of the modulated phase in uniaxial ferroelectrics, it has been shown that the positions of electronic levels are sensitive to the ratio of periods of the crystal field and the perturbation potential. Considering the energy states as prototypes of bands normalized by perturbation, one can come to the conclusion that the level of the states is the same a...

  18. The Mechanism of Aerodynamic Hysteresis for Sinusoidally Oscillating Delta Wings

    Institute of Scientific and Technical Information of China (English)

    黄国创; 王玉明; 曹桂兴

    1994-01-01

    An unsteady model of vortex system is developed to simulate the phenomena of aerodynamic hysteresis of sinusoidally oscillating delta wings.The dynamic behavior of leading-edge separation vortices simulated by the present method is in qualitative agreement with that of flow visualization by Gad-el-Hak and Ho.The calculated lift hysteresis loops are in quantitative agreement with the force measurements in the tunnel.The aerodynamic mechanism of the hysteresis phenomena is further investigated by the present method.

  19. Global map of lithosphere thermal thickness on a 1 deg x 1 deg grid - digitally available

    Science.gov (United States)

    Artemieva, Irina

    2014-05-01

    This presentation reports a 1 deg ×1 deg global thermal model for the continental lithosphere (TC1). The model is digitally available from the author's web-site: www.lithosphere.info. Geotherms for continental terranes of different ages (early Archean to present) are constrained by reliable data on borehole heat flow measurements (Artemieva and Mooney, 2001), checked with the original publications for data quality, and corrected for paleo-temperature effects where needed. These data are supplemented by cratonic geotherms based on xenolith data. Since heat flow measurements cover not more than half of the continents, the remaining areas (ca. 60% of the continents) are filled by the statistical numbers derived from the thermal model constrained by borehole data. Continental geotherms are statistically analyzed as a function of age and are used to estimate lithospheric temperatures in continental regions with no or low quality heat flow data. This analysis requires knowledge of lithosphere age globally. A compilation of tectono-thermal ages of lithospheric terranes on a 1 deg × 1 deg grid forms the basis for the statistical analysis. It shows that, statistically, lithospheric thermal thickness z (in km) depends on tectono-thermal age t (in Ma) as: z=0.04t+93.6. This relationship formed the basis for a global thermal model of the continental lithosphere (TC1). Statistical analysis of continental geotherms also reveals that this relationship holds for the Archean cratons in general, but not in detail. Particularly, thick (more than 250 km) lithosphere is restricted solely to young Archean terranes (3.0-2.6 Ga), while in old Archean cratons (3.6-3.0 Ga) lithospheric roots do not extend deeper than 200-220 km. The TC1 model is presented by a set of maps, which show significant thermal heterogeneity within continental upper mantle. The strongest lateral temperature variations (as large as 800 deg C) are typical of the shallow mantle (depth less than 100 km). A map of the

  20. Analysis of event-related potentials (ERP) by damped sinusoids.

    Science.gov (United States)

    Demiralp, T; Ademoglu, A; Istefanopulos, Y; Gülçür, H O

    1998-06-01

    Several researchers propose that event-related potentials (ERPs) can be explained by a superposition of transient oscillations at certain frequency bands in response to external or internal events. The transient nature of the ERP is more suitable to be modelled as a sum of damped sinusoids. These damped sinusoids can be completely characterized by four sets of parameters, namely the amplitude, the damping coefficient, the phase and the frequency. The Prony method is used to estimate these parameters. In this study, the long-latency auditory-evoked potentials (AEP) and the auditory oddball responses (P300) of 10 healthy subjects are analysed by this method. It is shown that the original waveforms can be reconstructed by summing a small number of damped sinusoids. This allows for a parsimonious representation of the ERPs. Furthermore, the method shows that the oddball target responses contain higher amplitude, slower delta and slower damped theta components than those of the AEPs. With this technique, we show that the differentiation of sensory and cognitive potentials are not inherent in their overall frequency content but in their frequency components at certain bands.

  1. Fibronectin Extra Domain A Promotes Liver Sinusoid Repair following Hepatectomy

    Science.gov (United States)

    Sackey-Aboagye, Bridget; Olsen, Abby L.; Mukherjee, Sarmistha M.; Ventriglia, Alexander; Yokosaki, Yasuyuki; Greenbaum, Linda E.; Lee, Gi Yun; Naga, Hani

    2016-01-01

    Liver sinusoidal endothelial cells (LSECs) are the main endothelial cells in the liver and are important for maintaining liver homeostasis as well as responding to injury. LSECs express cellular fibronectin containing the alternatively spliced extra domain A (EIIIA-cFN) and increase expression of this isoform after liver injury, although its function is not well understood. Here, we examined the role of EIIIA-cFN in liver regeneration following partial hepatectomy. We carried out two-thirds partial hepatectomies in mice lacking EIIIA-cFN and in their wild type littermates, studied liver endothelial cell adhesion on decellularized, EIIIA-cFN-containing matrices and investigated the role of cellular fibronectins in liver endothelial cell tubulogenesis. We found that liver weight recovery following hepatectomy was significantly delayed and that sinusoidal repair was impaired in EIIIA-cFN null mice, especially females, as was the lipid accumulation typical of the post-hepatectomy liver. In vitro, we found that liver endothelial cells were more adhesive to cell-deposited matrices containing the EIIIA domain and that cellular fibronectin enhanced tubulogenesis and vascular cord formation. The integrin α9β1, which specifically binds EIIIA-cFN, promoted tubulogenesis and adhesion of liver endothelial cells to EIIIA-cFN. Our findings identify a role for EIIIA-cFN in liver regeneration and tubulogenesis. We suggest that sinusoidal repair is enhanced by increased LSEC adhesion, which is mediated by EIIIA-cFN. PMID:27741254

  2. Phase extraction based on sinusoidal extreme strip phase shifting method

    Science.gov (United States)

    Hui, Mei; Liu, Ming; Dong, Liquan; Liu, Xiaohua; Zhao, Yuejin

    2015-08-01

    Multiple synthetic aperture imaging can enlarge pupil diameter of optical systems, and increase system resolution. Multiple synthetic aperture imaging is a cutting-edge topic and research focus in recent years, which is prospectively widely applied in fields like astronomical observations and aerospace remote sensing. In order to achieve good imaging quality, synthetic aperture imaging system requires phase extraction of each sub-aperture and co-phasing of whole aperture. In the project, an in-depth study about basic principles and methods of segments phase extraction was done. The study includes: application of sinusoidal extreme strip light irradiation phase shift method to extract the central dividing line to get segment phase extraction information, and the use of interference measurement to get the aperture phase extraction calibration coefficients of spherical surface. Study about influence of sinusoidal extreme strip phase shift on phase extraction, and based on sinusoidal stripe phase shift from multiple linear light sources of the illumination reflected image, to carry out the phase shift error for inhibiting the effect in the phase extracted frame.

  3. Sinusoidal synthesis based adaptive tracking for rotating machinery fault detection

    Science.gov (United States)

    Li, Gang; McDonald, Geoff L.; Zhao, Qing

    2017-01-01

    This paper presents a novel Sinusoidal Synthesis Based Adaptive Tracking (SSBAT) technique for vibration-based rotating machinery fault detection. The proposed SSBAT algorithm is an adaptive time series technique that makes use of both frequency and time domain information of vibration signals. Such information is incorporated in a time varying dynamic model. Signal tracking is then realized by applying adaptive sinusoidal synthesis to the vibration signal. A modified Least-Squares (LS) method is adopted to estimate the model parameters. In addition to tracking, the proposed vibration synthesis model is mainly used as a linear time-varying predictor. The health condition of the rotating machine is monitored by checking the residual between the predicted and measured signal. The SSBAT method takes advantage of the sinusoidal nature of vibration signals and transfers the nonlinear problem into a linear adaptive problem in the time domain based on a state-space realization. It has low computation burden and does not need a priori knowledge of the machine under the no-fault condition which makes the algorithm ideal for on-line fault detection. The method is validated using both numerical simulation and practical application data. Meanwhile, the fault detection results are compared with the commonly adopted autoregressive (AR) and autoregressive Minimum Entropy Deconvolution (ARMED) method to verify the feasibility and performance of the SSBAT method.

  4. Global map of lithosphere thermal thickness on a 1 deg x 1 deg grid - digitally available

    DEFF Research Database (Denmark)

    Artemieva, Irina

    2014-01-01

    than 250 km) lithosphere is restrictedsolely to young Archean terranes (3.0–2.6 Ga), while in old Archean cratons (3.6–3.0 Ga) lithospheric roots donot extend deeper than 200–220 km.The TC1 model is presented by a set of maps, which show significant thermal heterogeneity within continentalupper mantle......This presentation reports a 1 deg 1 deg global thermal model for the continental lithosphere (TC1). The modelis digitally available from the author’s web-site: www.lithosphere.info.Geotherms for continental terranes of different ages (early Archean to present) are constrained by reliabledata...... of the continents, the remaining areas (ca. 60% ofthe continents) are filled by the statistical numbers derived from the thermal model constrained by boreholedata. Continental geotherms are statistically analyzed as a function of age and are used to estimate lithospherictemperatures in continental regions...

  5. Experimental measurement of the solubility of bismuth phases in water vapor from 220 deg. C to 300 deg. C: Implications for ore formation

    Energy Technology Data Exchange (ETDEWEB)

    Kruszewski, Jason M. [Department of Geological Sciences, University of Idaho, Moscow, ID 83844-3022 (United States); Wood, Scott A., E-mail: swood@uidaho.edu [Department of Geological Sciences, University of Idaho, Moscow, ID 83844-3022 (United States)

    2009-04-15

    Preliminary measurements were carried out of the solubility of the O{sub 2-}buffering assemblage bismuth + bismite (Bi{sub 2}O{sub 3}) in aqueous liquid-vapor and vapor-only systems at temperatures of 220, 250 and 300 deg. C. All experiments were carried out in Ti reaction vessels and were designed such that the Bi solids were contained in a silica tube that prevented contact with liquid water at any time during the experiment. Two blank (no Bi solids present) liquid-vapor experiments at 220 deg. C yielded Bi concentrations ({+-}1{sigma}) in the condensed liquid of 0.22 {+-} 0.02 mg/L, whereas the solubility measurements at this temperature yielded an average value of approximately 6 {+-} 9 mg/L, with replicate experiments ranging from 0.3 to 26 mg/L. Although the 6 mg/L value is associated with a considerable degree of uncertainty, the experiments do indicate transport of Bi through the vapor phase. Measured Bi concentrations in the condensed liquid at 250 deg. C were in the same range as those at 220 deg. C, whereas those at 300 deg. C were significantly lower (i.e., all below the blank value). Vapor-only experiments necessarily contained much smaller initial volumes of water, thereby making the results more susceptible to contamination. Single blank runs at 220 and 300 deg. C yielded Bi concentrations of 82 and 16 mg/L, respectively. Measured concentrations ({+-}1{sigma}) of Bi in the vapor-only solubility experiments at 220 deg. C were 235 {+-} 78 mg/L for an initial water volume of 0.5 mL, and at 300 deg. C were 56 {+-} 30 mg/L and 33 {+-} 21 for initial water volumes of 1 and 2 mL, respectively, suggesting strong preferential partitioning of Bi into the vapor. The results indicate a negative dependence of Bi solubility on temperature, but are inconclusive with respect to the dependence of Bi solubility on water density or fugacity. The experiments reported here suggest that significant Bi transport is possible in the vapor phase. Comparison of the liquid

  6. OMP Peptides Activate the DegS Stress-Sensor Protease by a Relief of Inhibition Mechanism

    Energy Technology Data Exchange (ETDEWEB)

    Sohn, Jungsan; Grant, Robert A.; Sauer, Robert T.; MIT

    2010-03-19

    In the E. coli periplasm, C-terminal peptides of misfolded outer-membrane porins (OMPs) bind to the PDZ domains of the trimeric DegS protease, triggering cleavage of a transmembrane regulator and transcriptional activation of stress genes. We show that an active-site DegS mutation partially bypasses the requirement for peptide activation and acts synergistically with mutations that disrupt contacts between the protease and PDZ domains. Biochemical results support an allosteric model, in which these mutations, active-site modification, and peptide/substrate binding act in concert to stabilize proteolytically active DegS. Cocrystal structures of DegS in complex with different OMP peptides reveal activation of the protease domain with varied conformations of the PDZ domain and without specific contacts from the bound OMP peptide. Taken together, these results indicate that the binding of OMP peptides activates proteolysis principally by relieving inhibitory contacts between the PDZ domain and the protease domain of DegS.

  7. La poesia sabiana degli Anni Venti

    Directory of Open Access Journals (Sweden)

    Atilij Rakar

    1975-11-01

    Full Text Available Muovendo da un confronto fra il Saba del primo Canzoniere e le Figure e canti coi quali l'opera del poeta triestino continua negli anni venti, l'autore cerca di individuare i caratteri che meglio definiscono la poesia sabiana di questo secondo periodo. Messi in evidenza alcuni temi su cui verte il discorso sabiano fin delle Poesie dell'adolescenza e giovanili, le opere degli anni venti si rivelano come esiti di un poliforme compendio in cui il poeta vuol chiarire il senso del cammino percorso e comp:tendere quelle che sono le ragioni prime del suo poetare. Si manifestano qui, anche in maniera esplicita, alcuni motivi fondamentali del Canzionere: basti pensare, ad esempio, a Il borgo che offre la chiave per l'interprezazione di tutto un filone della tematica sabiana, o alle Fughe, con le quali il poeta vuol esprimere l'essenza del proprio sentire. La poetica delle »figure« e dei »canti« composti negli anni venti, non segnerebbe dunque una conversione di Saba ai »miti della forma«, come inducono a credere anche certe apostrofi del poeta stesso, rna può esser definita solo se vista in funzione dei contenuti che determinano il suo formarsi.

  8. Spin Interference in Rashba 2DEG Systems

    Science.gov (United States)

    Nitta, Junsaku

    The gate controllable SOI provides useful information about spin interference.1 Spin interference effects are studied in two different interference loop structures. It is known that sample specific conductance fluctuations affect the conductance in the interference loop. By using array of many interference loops, we carefully pick up TRS Altshuler-Aronov-Spivak (AAS)-type oscillation which is not sample specific and depends on the spin phase. The experimentally obtained gate voltage dependence of AAS oscillations indicates that the spin precession angle can be controlled by the gate voltage.2 We demonstrate the time reversal Aharonov-Casher (AC) effect in small arrays of mesoscopic rings.3 By using an electrostatic gate we can control the spin precession angle rate and follow the AC phase over several interference periods. We also see the second harmonic of the AC interference, oscillating with half the period. The spin interference is still visible after more than 20π precession angle. We have proposed a Stern-Gerlach type spin filter based on the Rashba SOI.4 A spatial gradient of effective magnetic field due to the nonuniform SOI separates spin up and down electrons. This spin filter works even without any external magnetic fields and ferromagnetic contacts. We show the semiconductor/ferromagnet hybrid structure is an effective way to detect magnetization process of submicron magnets. The problem of the spin injection from ferromagnetic contact into 2DEG is also disicussed. Note from Publisher: This article contains the abstract only.

  9. Evaluation of reconstruction arc in myocardial SPECT imaging using a cardiac phantom. Comparison between 360deg and 180deg arcs

    Energy Technology Data Exchange (ETDEWEB)

    Kashikura, Kenichi [Japan Science and Technology Corp., Tokyo (Japan); Kashikura, Akemi; Terada, Shinichirou; Kobayashi, Hideki

    1996-10-01

    In order to investigate the effect of reconstruction arc on myocardial SPECT images, a series of phantom studies was performed with and without plastic chambers simulating perfusion defects using {sup 201}Tl and {sup 99m}Tc. Coefficient of variations (CV) of the counts among the ROIs and defect contrast were evaluated in 360deg and 180deg images reconstructed from the same 360deg projection data. Reconstruction processes were identical for all images. In the absence of defects, the CV of the counts were approximately the same in 360deg and 180deg images. The CV of the counts in the 360deg {sup 201}Tl image, among 4 defects located on the anterior, lateral, inferoposterior, and septal walls, was superior to those in the 180deg images. In contrast, in the {sup 99m}Tc images, the CV of the counts among the 4 defects in the 180deg image was superior to those of the 360deg image. The defect contrast was changed both by the location of the defect and by the reconstruction arc ({sup 201}Tl, {sup 99m}Tc). The defect contrast of the 180deg images, in both {sup 201}Tl and {sup 99m}Tc experiments, was closer to the true contrast value as calculated by the count ratio between myocardium and defect. Although the defect contrast in the anterior, lateral and septal walls was more emphasized in the 180deg images, the defect contrast in the inferoposterior wall was less emphasized in the 180deg images compared to the 360deg ({sup 201}Tl, {sup 99m}Tc). (author)

  10. The structures of Arabidopsis Deg5 and Deg8 reveal new insights into HtrA proteases

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Wei [Chinese Academy of Sciences, 5 Datun Road, Chaoyang District, Beijing 100101 (China); University of Chinese Academy of Sciences, 19A Yuquan Road, Beijing 100049 (China); Gao, Feng [Chinese Academy of Sciences, 5 Datun Road, Chaoyang District, Beijing 100101 (China); Fan, Haitian; Shan, Xiaoyue [Chinese Academy of Sciences, 5 Datun Road, Chaoyang District, Beijing 100101 (China); University of Chinese Academy of Sciences, 19A Yuquan Road, Beijing 100049 (China); Sun, Renhua [Chinese Academy of Sciences, 20 Nanxincun, Haidian District, Beijing 100093 (China); University of Chinese Academy of Sciences, 19A Yuquan Road, Beijing 100049 (China); Liu, Lin, E-mail: liulin@ibcas.ac.cn [Chinese Academy of Sciences, 20 Nanxincun, Haidian District, Beijing 100093 (China); Gong, Weimin, E-mail: liulin@ibcas.ac.cn [Chinese Academy of Sciences, 5 Datun Road, Chaoyang District, Beijing 100101 (China)

    2013-05-01

    The crystal structures of Arabidopsis Deg5 and Deg8 have been determined to resolutions of 2.6 and 2.0 Å, respectively, revealing novel structural features of HtrA proteases. Plant Deg5 and Deg8 are two members of the HtrA proteases, a family of oligomeric serine endopeptidases that are involved in a variety of protein quality-control processes. These two HtrA proteases are located in the thylakoid lumen and participate in high-light stress responses by collaborating with other chloroplast proteins. Deg5 and Deg8 degrade photodamaged D1 protein of the photosystem II reaction centre, allowing its in situ replacement. Here, the crystal structures of Arabidopsis thaliana Deg5 (S266A) and Deg8 (S292A) are reported at 2.6 and 2.0 Å resolution, respectively. The Deg5 trimer contains two calcium ions in a central channel, suggesting a link between photodamage control and calcium ions in chloroplasts. Previous structures of HtrA proteases have indicated that their regulation usually requires C-terminal PDZ domain(s). Deg5 is unique in that it contains no PDZ domain and the trimeric structure of Deg5 (S266A) reveals a novel catalytic triad conformation. A similar triad conformation is observed in the hexameric structure of the single PDZ-domain-containing Deg8 (S292A). These findings suggest a novel activation mechanism for plant HtrA proteases and provide structural clues to their function in light-stress response.

  11. ISAR active jamming method based on sinusoidal modulation

    Institute of Scientific and Technical Information of China (English)

    Yu Zhang; Congfeng Liu; Yan Zhu

    2015-01-01

    It is potential y useful to perform deception or cover jamming using the rotating angular reflectors since they can form deception echoes along range and azimuth. Inspired by the cohe-rent jamming and micro-motion modulation, a novel active method is proposed for inverse synthetic aperture radar (ISAR). Radar pulses are sampled and frequency-modulated along azimuth by si-nusoidal signal, and then the jamming signals are retransmitted to the radar and the jamming images are induced after ISAR imaging. Therein, the jamming principle, key parameters and the jamming effect are discussed. The simulated data verify the effectiveness of the jamming method.

  12. On a method of perfect regression using sinusoidal expansion

    CERN Document Server

    Sinha, Nilotpal Kanti

    2011-01-01

    We present a new method of weighted least square regression that gives a curve of fit with any desired degree of accuracy for a given set of data points. By applying this iterative process infinitely, we show that every finite set of coplanar points can be expanded as a sinusoidal series in infinitely many ways. Thus, given any set of finite data points, we can obtain infinitely many perfect regression curves which give a perfect match between the given data points and the values given by the regression.

  13. Neutron irradiation of silicon diodes at temperatures of +20deg C and -20deg C

    Energy Technology Data Exchange (ETDEWEB)

    Anghinolfi, F.; Glaser, M.; Heijne, E.H.M.; Jarron, P.; Lemeilleur, F.; Occelli, E.; Poppleton, A. (CERN, Geneva (Switzerland)); Bardos, R.; Gorfine, G.; Moorhead, G.; Taylor, G.; Tovey, S. (School of Physics, Univ. Melbourne, Parkville (Australia)); Bates, S.J.; Munday, D.J.; Parker, M.A. (Cavendish Lab., Univ. Cambridge (United Kingdom)); Bonino, R.; Clark, A.G.; Wu, X. (DPNC, Univ. Geneva (Switzerland)); Claussen, N.; Fretwurst, E.; Lindstroem, G.; Papendick, B.; Schulz, T.; Wunstorf, R. (Inst. fuer Experimentalphysik, Univ. Hamburg (Germany)); Goessling, C.; Klingenberg, R.; Pagel, H.; Pollmann, D.; Rolf, A. (Inst. fuer Physik, Univ. Dortmund (Germany)); Scampoli, P. (Dipt. di Fisica, Univ. Perugia (Italy) INFN, Sezione Perugia (Italy)); Weidberg, A.R. (Dept. of Nuclear Physics, Oxford Univ. (United Kingdom)); RD2 Collaboration

    1993-03-01

    We report measurements of the behaviour of silicon diodes when exposed to integrated neutron doses of up to 5x10[sup 13] neutrons/cm[sup 2]. The measurements have been made at diode temperatures between room temperature and -20deg C. From measurements of the diode leakage current and depletion voltage, and consequent evaluations of the effective impurity concentration, the temperature dependence of these quantities is discussed in terms of the annealing behaviour of the diodes. Comments are made on the suitability of silicon as a detector medium for particle physics experiments at future accelerators. (orig.).

  14. Successful treatment of severe sinusoidal obstruction syndrome despite multiple organ failure with defibrotide after allogeneic stem cell transplantation: a case report

    Directory of Open Access Journals (Sweden)

    Behre Gerhard

    2009-03-01

    Full Text Available Abstract Introduction We report a case of sinusoidal obstruction syndrome, a typical and life-threatening complication after allogeneic stem-cell transplantation, successfully treated with defibrotide despite massive multiple organ failure. Case presentation A 64-year-old Caucasian woman underwent allogeneic peripheral blood stem-cell transplantation from her human leukocyte antigen-identical sister against aggressive lymphoplasmocytoid immunocytoma. Seven days later, the patient developed severe sinusoidal obstruction syndrome according to the modified Seattle criteria. We initiated treatment with defibrotide. Despite early treatment, multiple organ failure with kidney failure requiring dialysis and ventilator-dependent lung failure aggravated the clinical course. Furthermore, central nervous dysfunction occurred as well as transfusion refractory thrombocytopenia. Conclusion As highlighted in our report, defibrotide is the most promising drug in the treatment of the formerly, almost lethal, severe sinusoidal obstruction syndrome to date. This is demonstrated very clearly in our patient. She improved completely, even after renal, cerebral and respiratory failure.

  15. DegP Chaperone Suppresses Toxic Inner Membrane Translocation Intermediates

    Science.gov (United States)

    Braselmann, Esther; Chaney, Julie L.; Champion, Matthew M.

    2016-01-01

    The periplasm of Gram-negative bacteria includes a variety of molecular chaperones that shepherd the folding and targeting of secreted proteins. A central player of this quality control network is DegP, a protease also suggested to have a chaperone function. We serendipitously discovered that production of the Bordetella pertussis autotransporter virulence protein pertactin is lethal in Escherichia coli ΔdegP strains. We investigated specific contributions of DegP to secretion of pertactin as a model system to test the functions of DegP in vivo. The DegP chaperone activity was sufficient to restore growth during pertactin production. This chaperone dependency could be relieved by changing the pertactin signal sequence: an E. coli signal sequence leading to co-translational inner membrane (IM) translocation was sufficient to suppress lethality in the absence of DegP, whereas an E. coli post-translational signal sequence was sufficient to recapitulate the lethal phenotype. These results identify a novel connection between the DegP chaperone and the mechanism used to translocate a protein across the IM. Lethality coincided with loss of periplasmic proteins, soluble σE, and proteins regulated by this essential stress response. These results suggest post-translational IM translocation can lead to the formation of toxic periplasmic folding intermediates, which DegP can suppress. PMID:27626276

  16. DegP Chaperone Suppresses Toxic Inner Membrane Translocation Intermediates.

    Science.gov (United States)

    Braselmann, Esther; Chaney, Julie L; Champion, Matthew M; Clark, Patricia L

    2016-01-01

    The periplasm of Gram-negative bacteria includes a variety of molecular chaperones that shepherd the folding and targeting of secreted proteins. A central player of this quality control network is DegP, a protease also suggested to have a chaperone function. We serendipitously discovered that production of the Bordetella pertussis autotransporter virulence protein pertactin is lethal in Escherichia coli ΔdegP strains. We investigated specific contributions of DegP to secretion of pertactin as a model system to test the functions of DegP in vivo. The DegP chaperone activity was sufficient to restore growth during pertactin production. This chaperone dependency could be relieved by changing the pertactin signal sequence: an E. coli signal sequence leading to co-translational inner membrane (IM) translocation was sufficient to suppress lethality in the absence of DegP, whereas an E. coli post-translational signal sequence was sufficient to recapitulate the lethal phenotype. These results identify a novel connection between the DegP chaperone and the mechanism used to translocate a protein across the IM. Lethality coincided with loss of periplasmic proteins, soluble σE, and proteins regulated by this essential stress response. These results suggest post-translational IM translocation can lead to the formation of toxic periplasmic folding intermediates, which DegP can suppress.

  17. Involvement of DEG5 and DEG8 proteases in the turnover of the photosystem II reaction center D1 protein under heat stress in Arabidopsis thaliana

    Institute of Scientific and Technical Information of China (English)

    SUN XuWu; WANG LiYuan; ZHANG LiXin

    2007-01-01

    Deg5,deg8 and the double mutant,deg5deg8 of Arabidopsis thaliana were used to study the physiological role of the DEG proteases in the repair cycle of photosystem II (PSII) under heat stress. PSII activity in deg mutants showed increased sensitivity to heat stress,and the extent of this effect was greater in the double mutant,deg5deg8,than in the single mutants,deg5 and deg8. Degradation of the D1 protein was slower in the mutants than in the WT plants. Furthermore,the levels of other PSII reaction center proteins tested remained relatively stable in the mutant and WT plants following high-temperature treatment. Thus,our results indicate that DEG5 and DEG8 may have synergistic function in degradation of D1 protein under heat stress.

  18. The Prevalence of the 22 deg Halo in Cirrus Clouds

    Science.gov (United States)

    Diedenhoven, vanBastiaan

    2014-01-01

    Halos at 22 deg from the sun attributed to randomly-orientated, pristine hexagonal crystals are frequently observed through ice clouds. These frequent sightings of halos formed by pristine crystals pose an apparent inconsistency with the dominance of distorted, nonpristine ice crystals indicated by in situ and remote sensing data. Furthermore, the 46 deg halo, which is associated with pristine hexagonal crystals as well, is observed far less frequently than the 22 deg halo. Considering that plausible mechanisms that could cause crystal distortion such as aggregation, sublimation, riming and collisions are stochastic processes that likely lead to distributions of crystals with varying distortion levels, here the presence of the 22 deg and 46 deg halo features in phase functions of mixtures of pristine and distorted hexagonal ice crystals is examined. We conclude that the 22 deg halo feature is generally present if the contribution by pristine crystals to the total scattering cross section is greater than only about 10% in the case of compact particles or columns, and greater than about 40% for plates. The 46 deg halo feature is present only if the mean distortion level is low and the contribution of pristine crystals to the total scattering cross section is above about 20%, 50% and 70%, in the case of compact crystals, plates and columns, respectively. These results indicate that frequent sightings of 22 deg halos are not inconsistent with the observed dominance of distorted, non-pristine ice crystals. Furthermore, the low mean distortion levels and large contributions by pristine crystals needed to produce the 461 halo features provide a potential explanation of the common sighting of the 22 deg halo without any detectable 46 deg halo.

  19. Design and Optimization of Sinusoidal Formed Femur Prosthesis

    Directory of Open Access Journals (Sweden)

    Ahmet Zafer ŞENALP

    2015-01-01

    Full Text Available One of the major problems in hip replacement surgery is the hip replacement loosening. Hip replacement loosening occurs over time after the surgery and it is related to the discretization between the bone cement and prosthesis. The underlying factors of this situation are the stress occurring in the bone cement and the shape of the prosthesis. In this study, cortical and trabecular layers of the femur, bone cement and prosthesis were modeled. The models of bone cement and prosthesis were constructed parametrically and two different sinusoidal formed prostheses were developed unlike the former prostheses shapes. Analyses were conducted for these two different sinusoidal forms by using finite element method and optimization was conducted to obtain the appropriate prosthesis stem shape and bone cement thickness by using parametric modeling in finite element analyses. For finite element analyses and optimization, Ansys Workbench software was used and analyses were conducted for 316LS stainless steel material. Finally, the optimum prosthesis stem shape and bone cement thickness was determined by using the results of the analyses in the first stage

  20. Thixotropy and rheopexy of muscle fibers probed using sinusoidal oscillations.

    Directory of Open Access Journals (Sweden)

    David Altman

    Full Text Available Length changes of muscle fibers have previously been shown to result in a temporary reduction in fiber stiffness that is referred to as thixotropy. Understanding the mechanism of this thixotropy is important to our understanding of muscle function since there are many instances in which muscle is subjected to repeated patterns of lengthening and shortening. By applying sinusoidal length changes to one end of single permeabilized muscle fibers and measuring the force response at the opposite end, we studied the history-dependent stiffness of both relaxed and activated muscle fibers. For length change oscillations greater than 1 Hz, we observed thixotropic behavior of activated fibers. Treatment of these fibers with EDTA and blebbistatin, which inhibits myosin-actin interactions, quashed this effect, suggesting that the mechanism of muscle fiber thixotropy is cross-bridge dependent. We modeled a half-sarcomere experiencing sinusoidal length changes, and our simulations suggest that thixotropy could arise from force-dependent cross-bridge kinetics. Surprisingly, we also observed that, for length change oscillations less than 1 Hz, the muscle fiber exhibited rheopexy. In other words, the stiffness of the fiber increased in response to the length changes. Blebbistatin and EDTA did not disrupt the rheopectic behavior, suggesting that a non-cross-bridge mechanism contributes to this phenomenon.

  1. Propiedades de transporte de una superred de grafeno tipo sinusoidal

    Directory of Open Access Journals (Sweden)

    J. A. Briones-Torres

    2015-01-01

    Full Text Available En este trabajo usamos el método de la matriz de transferencia para estudiar el tunelamiento de los electrones de Dirac a través de superredes en grafeno. Consideramos una superred con potencial sinusoidal o polaridad invertida, para ello consideramos dos maneras de crearla, una por medio de sustratos mixtos junto con la aplicación de un campo perpendicular sobre el sustrato de Óxido de Silicio (SiO2, la otra por medio de potenciales alternados aplicados perpendicularmente sobre la sábana de grafeno. Calculamos las propiedades de transmisión, transporte y estructura electrónica, variando diferentes parámetros como ángulo de incidencia, anchos de pozos y barreras y diferente número de barreras. Se encontró (1 el importante papel que juega el efecto Klein en tales estructuras, (2 las propiedades de transmisión y transporte presentan cierta simetría respecto del origen de la energía, y (3 el carácter sinusoidal del sistema trae consigo una baja en el nivel de energía de las subbandas en el espectro de estados acotados, además las degenera y origina que la apertura-cierre de las minibandas sea en el mismo nivel de energía.

  2. Sinusoidal current and stress evolutions in lithium-ion batteries

    Science.gov (United States)

    Yang, Xiao-Guang; Bauer, Christoph; Wang, Chao-Yang

    2016-09-01

    Mechanical breakdown of graphite materials due to diffusion-induced stress (DIS) is a key aging mechanism of lithium-ion batteries. In this work, electrochemical-thermal coupled model along with a DIS model is developed to study the DIS distribution across the anode thickness. Special attention is paid to the evolution behavior of surface tangential stress (STS) in the discharge process for graphite at different locations of the anode. For the first time, we report that the evolution of STS, as well as local current, at all locations of the anode, evolve like sinusoidal waves in the discharge process with several crests and troughs. The staging behavior of graphite active material, in particular the sharp change of open-circuit potential (OCP) of graphite in the region between two plateaus, is found to be the root cause for the sinusoidal patterns of current and stress evolution. Furthermore, the effects of various parameters, such as starting state of charge, discharge C-rate and electrode thickness on the current and stress evolutions are investigated.

  3. Method and apparatus for spur-reduced digital sinusoid synthesis

    Science.gov (United States)

    Zimmerman, George A. (Inventor); Flanagan, Michael J. (Inventor)

    1995-01-01

    A technique for reducing the spurious signal content in digital sinusoid synthesis is presented. Spur reduction is accomplished through dithering both amplitude and phase values prior to word-length reduction. The analytical approach developed for analog quantization is used to produce new bounds on spur performance in these dithered systems. Amplitude dithering allows output word-length reduction without introducing additional spurs. Effects of periodic dither similar to that produced by a pseudo-noise (PN) generator are analyzed. This phase dithering method provides a spur reduction of 6(M + 1) dB per phase bit when the dither consists of M uniform variates. While the spur reduction is at the expense of an increase in system noise, the noise power can be made white, making the power spectral density small. This technique permits the use of a smaller number of phase bits addressing sinusoid look-up tables, resulting in an exponential decrease in system complexity. Amplitude dithering allows the use of less complicated multipliers and narrower data paths in purely digital applications, as well as the use of coarse-resolution, highly-linear digital-to-analog converters (DAC's) to obtain spur performance limited by the DAC linearity rather than its resolution.

  4. Flexure fatigue testing of 90 deg graphite/epoxy composites

    Science.gov (United States)

    Peck, Ann Nancy W.

    1995-01-01

    A great deal of research has been performed characterizing the in-plane fiber-dominated properties, under both static and fatigue loading, of advanced composite materials. To the author's knowledge, no study has been performed to date investigating fatigue characteristics in the transverse direction. This information is important in the design of bonded composite airframe structure where repeated, cyclic out-of-plane bending may occur. Recent tests characterizing skin/stringer debond failures in reinforced composite panels where the dominant loading in the skin is flexure along the edge of the frame indicate failure initiated either in the skin or else the flange, near the flange tip. When failure initiated in the skin, transverse matrix cracks formed in the surface skin ply closest to the flange and either initiated delaminations or created matrix cracks in the next lower ply, which in turn initiated delaminations. When failure initiated in the flanges, transverse cracks formed in the flange angle ply closest to the skin and initiated delamination. In no configuration did failure propagate through the adhesive bond layer. For the examined skin/flange configurations, the maximum transverse tension stress at failure correlates very well with the transverse tension strength of the composites. Transverse tension strength (static) data of graphite epoxy composites have been shown to vary with the volume of material stressed. As the volume of material stressed increased, the strength decreased. A volumetric scaling law based on Weibull statistics can be used to predict the transverse strength measurements. The volume dependence reflects the presence of inherent flaws in the microstructure of the lamina. A similar approach may be taken to determine a volume scale effect on the transverse tension fatigue behavior of graphite/epoxy composites. The objective of this work is to generate transverse tension strength and fatigue S-N characteristics for composite materials using

  5. Hepatic Sinusoidal Obstruction Syndrome Induced by Non-transplant Chemotherapy for Non-Hodgkin Lymphoma

    Science.gov (United States)

    Sakumura, Miho; Tajiri, Kazuto; Miwa, Shigeharu; Nagata, Kohei; Kawai, Kengo; Miyazono, Takayoshi; Arita, Kotaro; Wada, Akinori; Murakami, Jun; Sugiyama, Toshiro

    2017-01-01

    Hepatic sinusoidal obstruction syndrome (SOS), a serious complication that mainly occurs after hematopoietic-stem cell transplantation (HSCT), is caused by damage to the sinusoidal endothelial cells after the obstruction of the sinusoid. Recently, hepatic SOS was reported to occur after non-HSCT chemotherapies. This report describes a patient who experienced hepatic SOS after non-HSCT chemotherapy for non-Hodgkin lymphoma. A liver biopsy showed the slight dilatation of the hepatic sinusoid, which may be indicative of hepatic SOS. Hepatic SOS should be included in the differential diagnosis of patients with severe liver injury following the administration of chemotherapy regimens that are toxic to the vascular endothelial cells. PMID:28202860

  6. The sinusoidal periodicity nature for M>=5 global earthquakes

    CERN Document Server

    Zhang, Z X

    2016-01-01

    By using the M>=5 global earthquake data for Jan. 1950 to Dec. 2015, we performed statistical analyses for the parameters magnitude, time, and depth on a yearly scale. The magnitude spectrum, which is the earthquake number accumulated at different magnitudes, had an exponential distribution. For the first time, we report a very significant characteristic of the sinusoidal periodic variation in the spectral index. The cycle of the sine function fitting was 30.98 years. The concept of annual equivalent total magnitude (AETM) of total released energy for each year was introduced and the trend variation of AETM year by year was studied. Overall, the global AETM of earthquakes with M>=5 displayed a certain upward trend as the years elapsed. At the same time, the change of the average epicenter depth of the global earthquakes (M>=5) in each year was analyzed.

  7. Phonological awareness and sinusoidal amplitude modulation in phonological dislexia

    Directory of Open Access Journals (Sweden)

    Yolanda Peñaloza-López

    2016-04-01

    Full Text Available ABSTRACT Objective Dyslexia is the difficulty of children in learning to read and write as results of neurological deficiencies. The objective was to test the Phonological awareness (PA and Sinusoidal amplitude modulation (SAM threshold in children with Phonological dyslexia (PD. Methods We performed a case-control, analytic, cross sectional study. We studied 14 children with PD and 14 control children from 7 to 11 years of age, by means of PA measurement and by SAM test. The mean age of dyslexic children was 8.39 years and in the control group was 8.15. Results Children with PD exhibited inadequate skills in PA, and SAM. We found significant correlations between PA and SAM at 4 Hertz frequency, and calculated regression equations that predicts between one-fourth and one-third of variance of measurements. Conclusion Alterations in PA and SAM found can help to explain basis of deficient language processing exhibited by children with PD.

  8. New Realizations of Single OTRA-Based Sinusoidal Oscillators

    Directory of Open Access Journals (Sweden)

    Hung-Chun Chien

    2014-01-01

    Full Text Available This study proposes three new sinusoidal oscillators based on an operational transresistance amplifier (OTRA. Each of the proposed oscillator circuits consists of one OTRA combined with a few passive components. The first circuit is an OTRA-based minimum RC oscillator. The second circuit is capable of providing independent control on the condition of oscillation without affecting the oscillation frequency. The third circuit exhibits independent control of oscillation frequency through a capacitor. This study first introduces the OTRA and the related formulations of the proposed oscillator circuits, and then discusses the nonideal effects, sensitivity analyses, and frequency stability of the presented circuits. The proposed oscillators exhibit low sensitivities and good frequency stability. Because the presented circuits feature low impedance output, they can be connected directly to the next stage without cascading additional voltage buffers. HSPICE simulations and experimental results confirm the feasibility of the new oscillator circuits.

  9. Log-Domain Current-mode Quadrature Sinusoidal Oscillator

    Directory of Open Access Journals (Sweden)

    P. Prommee

    2011-09-01

    Full Text Available A log-domain current-mode quadrature sinusoidal oscillator based on lossless integrators is presented. The circuit is a direct realization of a first-order differential equation for obtaining the lossy and lossless integrators. Each of the log-domain lossless integrators is realized by using only NPN transistors and a grounded capacitor for achieving low-power and fast response. The proposed oscillator uses two-lossless integrator loop which can be electronically tuned through bias currents. A validated BJT model which is used in SPICE simulation operated from a single power supply as low as 2.5V. The oscillation frequency is controlled over four decades of frequency. The total harmonic distortions for two-phases QSO (12MHz is obtained around 0.93% which enables fully integrated in telecommunication systems. The proposed circuit is also suitable for high-frequency applications. Nonideality studies are included and PSpice simulation results confirm the theoretical results.

  10. Pulsating laminar pipe flows with sinusoidal mass flux variations

    Science.gov (United States)

    Ünsal, B.; Ray, S.; Durst, F.; Ertunç, Ö.

    2005-11-01

    Combined analytical and experimental investigation of sinusoidal mass flow-controlled, pulsating, laminar and fully developed pipe flow was carried out. The experimental investigation employed a mass flow control unit built at LSTM-Erlangen for the present investigation. For the analytical investigation, the equations describing such flows were normalized to allow for a general solution, depending only on the normalized amplitude mA* of the mass flow pulsation and the normalized frequency F. The analytical and experimental results are presented in this normalized way and it is shown that good agreement between the results of the authors is obtained. A diagram is presented for the condition of flow reversal in terms of the dimensionless frequency F and the mass flow rate amplitude mA*.

  11. Phonological awareness and sinusoidal amplitude modulation in phonological dislexia.

    Science.gov (United States)

    Peñaloza-López, Yolanda; Herrera-Rangel, Aline; Pérez-Ruiz, Santiago J; Poblano, Adrián

    2016-04-01

    Dyslexia is the difficulty of children in learning to read and write as results of neurological deficiencies. The objective was to test the Phonological awareness (PA) and Sinusoidal amplitude modulation (SAM) threshold in children with Phonological dyslexia (PD). We performed a case-control, analytic, cross sectional study. We studied 14 children with PD and 14 control children from 7 to 11 years of age, by means of PA measurement and by SAM test. The mean age of dyslexic children was 8.39 years and in the control group was 8.15. Children with PD exhibited inadequate skills in PA, and SAM. We found significant correlations between PA and SAM at 4 Hertz frequency, and calculated regression equations that predicts between one-fourth and one-third of variance of measurements. Alterations in PA and SAM found can help to explain basis of deficient language processing exhibited by children with PD.

  12. Operational Transresistance Amplifier-Based Multiphase Sinusoidal Oscillators

    Directory of Open Access Journals (Sweden)

    Rajeshwari Pandey

    2011-01-01

    Full Text Available Multiphase sinusoidal oscillator circuits are presented which utilize Operational Transresistance Amplifier (OTRA as the active element. The first circuit produces n odd-phase oscillations of equal amplitudes and equally spaced in phase. The second circuit is capable of producing n odd- or even- phase oscillations equally spaced in phase. An alternative approach is discussed in the third circuit, which utilizes a single-phase tunable oscillator circuit which is used to inject signals into a phase shifter circuits. An automatic gain control (AGC circuit has been implemented for the second and third circuit. The circuits are simple to realize and have a low component count. PSPICE simulations have been given to verify the theoretical analysis. The experimental outcome corroborates the theoretical propositions and simulated results.

  13. Some New Results on the Estimation of Sinusoids in Noise

    DEFF Research Database (Denmark)

    Nielsen, Jesper Kjær

    2012-01-01

    This thesis is concerned with the problem of estimating sinusoidal parameters from noisy observations. This field of research is applicable to solving problems in a large number of areas such as music and speech processing, electrocardiography, seismology, radar and sonar processing, astronomy...... to these previously proposed methods. The second part of this thesis contains the contributions. First, the model comparison and selection problem is considered for a general non-linear model. In this connection, a few new model comparison methods are proposed and demonstrated to perform better than existing methods......-of-arrival, and it is shown that compressed sensing decreases the estimation accuracy of such parameters. Although the estimation problems considered in this thesis are primarily analysed in the context of speech and audio applications, the results are useful in a wider range of applications. Along these lines, the main...

  14. Masking of a brief probe by sinusoidal frequency modulation.

    Science.gov (United States)

    Edwards, B W; Viemeister, N F

    1997-02-01

    Contrary to level detection models, the thresholds for a brief-duration probe masked by a sinusoidal frequency modulation (FM) masker increases as the modulation index (beta) of FM increases [Zwicker, Acustica 31, 243-256 (1974)]. In this paper the reason for this phenomenon is investigated. In experiment 1, a 10-ms, 1-kHz probe was detected in the presence of an FM masker centered at 1 kHz and sinusoidally modulated at 16 Hz. Thresholds increased by over 15 dB with increasing beta, consistent with Zwicker's findings. In experiment 2, the instantaneous frequency changes of the masker used in experiment 1 were clipped and the resulting thresholds indicated that detection was determined primarily by the masker's total frequency excursion rather than by its instantaneous sweep rate. In experiment 3, the FM maskers from the first two experiments were passed through a roex filter centered at 1 kHz and the resulting envelope was used to amplitude modulate a 1-kHz tone, producing approximately the same effective envelope at 1 kHz as the FM maskers. Threshold functions for the amplitude modulated (AM) maskers were similar to those for their corresponding FM maskers. Thresholds increased by over 15 dB while the total energy of the AM masker decreased by over 10 dB, again contrary to standard level-detection models. The results from these experiments can be explained, at least qualitatively, by a model based on envelope shape discrimination: similarities between the envelopes of the masker alone and masker-plus-probe at the output of an auditory filter centered on the frequency of the probe are primarily responsible for the observed masking, particularly at large beta's.

  15. Representative Sinusoids for Hepatic Four-Scale Pharmacokinetics Simulations.

    Directory of Open Access Journals (Sweden)

    Lars Ole Schwen

    Full Text Available The mammalian liver plays a key role for metabolism and detoxification of xenobiotics in the body. The corresponding biochemical processes are typically subject to spatial variations at different length scales. Zonal enzyme expression along sinusoids leads to zonated metabolization already in the healthy state. Pathological states of the liver may involve liver cells affected in a zonated manner or heterogeneously across the whole organ. This spatial heterogeneity, however, cannot be described by most computational models which usually consider the liver as a homogeneous, well-stirred organ. The goal of this article is to present a methodology to extend whole-body pharmacokinetics models by a detailed liver model, combining different modeling approaches from the literature. This approach results in an integrated four-scale model, from single cells via sinusoids and the organ to the whole organism, capable of mechanistically representing metabolization inhomogeneity in livers at different spatial scales. Moreover, the model shows circulatory mixing effects due to a delayed recirculation through the surrounding organism. To show that this approach is generally applicable for different physiological processes, we show three applications as proofs of concept, covering a range of species, compounds, and diseased states: clearance of midazolam in steatotic human livers, clearance of caffeine in mouse livers regenerating from necrosis, and a parameter study on the impact of different cell entities on insulin uptake in mouse livers. The examples illustrate how variations only discernible at the local scale influence substance distribution in the plasma at the whole-body level. In particular, our results show that simultaneously considering variations at all relevant spatial scales may be necessary to understand their impact on observations at the organism scale.

  16. Nematic liquid crystals on sinusoidal channels: the zigzag instability

    Science.gov (United States)

    Silvestre, Nuno M.; Romero-Enrique, Jose M.; Telo da Gama, Margarida M.

    2017-01-01

    Substrates which are chemically or topographically patterned induce a variety of liquid crystal textures. The response of the liquid crystal to competing surface orientations, typical of patterned substrates, is determined by the anisotropy of the elastic constants and the interplay of the relevant lengths scales, such as the correlation length and the surface geometrical parameters. Transitions between different textures, usually with different symmetries, may occur under a wide range of conditions. We use the Landau-de Gennes free energy to investigate the texture of nematics in sinusoidal channels with parallel anchoring bounded by nematic-air interfaces that favour perpendicular (hometropic) anchoring. In micron size channels 5CB was observed to exhibit a non-trivial texture characterized by a disclination line, within the channel, which is broken into a zigzag pattern. Our calculations reveal that when the elastic anisotropy of the nematic does not favour twist distortions the defect is a straight disclination line that runs along the channel, which breaks into a zigzag pattern with a characteristic period, when the twist elastic constant becomes sufficiently small when compared to the splay and bend constants. The transition occurs through a twist instability that drives the defect line to rotate from its original position. The interplay between the energetically favourable twist distortions that induce the defect rotation and the liquid crystal anchoring at the surfaces leads to the zigzag pattern. We investigate in detail the dependence of the periodicity of the zigzag pattern on the geometrical parameters of the sinusoidal channels, which in line with the experimental results is found to be non-linear.

  17. The BLAST View of the Star Forming Region in Aquila (ell=45deg,b=0deg)

    CERN Document Server

    Rivera-Ingraham, Alana; Bock, James J; Chapin, Edward L; Devlin, Mark J; Dicker, Simon R; Griffin, Matthew; Gundersen, Joshua O; Halpern, Mark; Hargrave, Peter C; Hughes, David H; Klein, Jeff; Marsden, Gaelen; Martin, Peter G; Mauskopf, Philip; Netterfield, Calvin B; Olmi, Luca; Patanchon, Guillaume; Rex, Marie; Scott, Douglas; Semisch, Christopher; Truch, Matthew D P; Tucker, Carole; Tucker, Gregory S; Viero, Marco P; Wiebe, Donald V

    2010-01-01

    We have carried out the first general submillimeter analysis of the field towards GRSMC 45.46+0.05, a massive star forming region in Aquila. The deconvolved 6 deg^2 (3\\degree X 2\\degree) maps provided by BLAST in 2005 at 250, 350, and 500 micron were used to perform a preliminary characterization of the clump population previously investigated in the infrared, radio, and molecular maps. Interferometric CORNISH data at 4.8 GHz have also been used to characterize the Ultracompact HII regions (UCHIIRs) within the main clumps. By means of the BLAST maps we have produced an initial census of the submillimeter structures that will be observed by Herschel, several of which are known Infrared Dark Clouds (IRDCs). Our spectral energy distributions of the main clumps in the field, located at ~7 kpc, reveal an active population with temperatures of T~35-40 K and masses of ~10^3 Msun for a dust emissivity index beta=1.5. The clump evolutionary stages range from evolved sources, with extended HII regions and prominent IR ...

  18. THEORETICAL STUDY OF AN OSCILLATING WAVEFORM FUNCTION AND PARAMETERS FOR CONTROLLING THE NON-SINUSOIDAL OSCILLATION OF A MOLD

    Institute of Scientific and Technical Information of China (English)

    Ren Tingzhi; Liu Cai

    2004-01-01

    A new non-sinusoidal oscillation waveform is constructed for controlling the mold oscillation during continuous casting. Casting velocity and oscillation parameters are then established for a computer model of the continuous casting process. The waveform distortion coefficient ε of waveform function is close to the waveform distortion rate α, so ε is taken for ε when the basic parameters are selected initially. The waveform function can be created for the servo hydraulic system or the mechanical driving system. Industrial scale experiments show the waveform function is effective.

  19. Sinusoidal oscillators and waveform generators using modern electronic circuit building blocks

    CERN Document Server

    Senani, Raj; Singh, V K; Sharma, R K

    2016-01-01

    This book serves as a single-source reference to sinusoidal oscillators and waveform generators, using classical as well as a variety of modern electronic circuit building blocks. It provides a state-of-the-art review of a large variety of sinusoidal oscillators and waveform generators and includes a catalogue of over 600 configurations of oscillators and waveform generators, describing their relevant design details and salient performance features/limitations. The authors discuss a number of interesting, open research problems and include a comprehensive collection of over 1500 references on oscillators and non-sinusoidal waveform generators/relaxation oscillators. Offers readers a single-source reference to everything connected to sinusoidal oscillators and waveform generators, using classical as well as modern electronic circuit building blocks; Provides a state-of-the-art review of a large variety of sinusoidal oscillators and waveform generators; Includes a catalog of over 600 configurations of oscillato...

  20. Improved Sinusoid Analysis and Post-Processing in Parametric Audio Coding

    Institute of Scientific and Technical Information of China (English)

    周宏; 陈健

    2003-01-01

    This paper proposed improvements to the low bit rate parametric audio coder with sinusoid model as its kernel. Firstly, we propose a new method to effectively order and select the perceptually most important sinusoids. The sinusoid which contributes most to the reduction of overall NMR is chosen. Combined with our improved parametric psychoacoustic model and advanced peak riddling techniques, the number of sinusoids required can be greatly reduced and the coding efficiency can be greatly enhanced. A lightweight version is also given to reduce the amount of computation with only little sacrifice of performance. Secondly, we propose two enhancement techniques for sinusoid synthesis: bandwidth enhancement and line enhancement. With little overhead, the effective bandwidth can be extended one more octave; the timbre tends to sound much brighter, thicker and more beautiful.

  1. Orbital component extraction by time-variant sinusoidal modeling.

    Science.gov (United States)

    Sinnesael, Matthias; Zivanovic, Miroslav; De Vleeschouwer, David; Claeys, Philippe; Schoukens, Johan

    2016-04-01

    Accurately deciphering periodic variations in paleoclimate proxy signals is essential for cyclostratigraphy. Classical spectral analysis often relies on methods based on the (Fast) Fourier Transformation. This technique has no unique solution separating variations in amplitude and frequency. This characteristic makes it difficult to correctly interpret a proxy's power spectrum or to accurately evaluate simultaneous changes in amplitude and frequency in evolutionary analyses. Here, we circumvent this drawback by using a polynomial approach to estimate instantaneous amplitude and frequency in orbital components. This approach has been proven useful to characterize audio signals (music and speech), which are non-stationary in nature (Zivanovic and Schoukens, 2010, 2012). Paleoclimate proxy signals and audio signals have in nature similar dynamics; the only difference is the frequency relationship between the different components. A harmonic frequency relationship exists in audio signals, whereas this relation is non-harmonic in paleoclimate signals. However, the latter difference is irrelevant for the problem at hand. Using a sliding window approach, the model captures time variations of an orbital component by modulating a stationary sinusoid centered at its mean frequency, with a single polynomial. Hence, the parameters that determine the model are the mean frequency of the orbital component and the polynomial coefficients. The first parameter depends on geologic interpretation, whereas the latter are estimated by means of linear least-squares. As an output, the model provides the orbital component waveform, either in the depth or time domain. Furthermore, it allows for a unique decomposition of the signal into its instantaneous amplitude and frequency. Frequency modulation patterns can be used to reconstruct changes in accumulation rate, whereas amplitude modulation can be used to reconstruct e.g. eccentricity-modulated precession. The time-variant sinusoidal model

  2. Creep crack growth in a reactor pressure vessel steel at 360 deg C

    Energy Technology Data Exchange (ETDEWEB)

    Rui Wu; Seitisleam, F.; Sandstroem, R. [Swedish Institute for Metals Research, Stockholm (Sweden)

    1998-12-31

    Plain creep (PC) and creep crack growth (CCG) tests at 360 deg C and post metallography were carried out on a low alloy reactor pressure vessel steel (ASTM A508 class 2) with different microstructures. Lives for the CCG tests were shorter than those for the PC tests and this is more pronounced for simulated heat affected zone microstructure than for the parent metal at longer lives. For the CCG tests, after initiation, the cracks grew constantly and intergranularly before they accelerated to approach rupture. The creep crack growth rate is well described by C*. The relations between reference stress, failure time and steady crack growth rate are presented for the CCG tests. It is demonstrated that the failure stress due to CCG is considerably lower than the yield stress at 360 deg C. Consequently, the CCG will control the static strength of a reactor vessel. (orig.) 17 refs.

  3. FORCE REDUCTION OF FLOW AROUND A SINUSOIDAL WAVY CYLINDER

    Institute of Scientific and Technical Information of China (English)

    ZOU Lin; LIN Yu-feng

    2009-01-01

    A large eddy simulation of cross-flow around a sinusoidal wavy cylinder at Re=3000 was performed and the load cell measurement was introduced for the validation test. The mean flow field and the near wake flow structures were presented and compared with those for a circular cylinder at the same Reynolds number. The mean drag coefficient for the wavy cylinder is smaller than that for a corresponding circular cylinder due to the formation of a longer wake vortex generated by the wavy cylinder. The fluctuating lift coefficient of the wavy cylinder is also greatly reduced. This kind of wavy surface leads to the formation of 3-D free shear layers which are more stable than purely 2-D free shear layers. Such free shear layers only roll up into mature vortices at further downstream position and significantly modify the near wake structures and the pressure distributions around the wavy cylinder. Moreover, the simulations in laminar flow condition were also performed to investigate the effect of Reynolds number on force reduction control.

  4. Four-Wire Delta Service Sinusoidal Operation and Compensation Simulator

    Directory of Open Access Journals (Sweden)

    Vicente León-Martínez

    2015-10-01

    Full Text Available An off-line simulator based on Excel used to evaluate the operation of four-wire delta (4WD services as well as the effects of reactive and imbalance compensators in sinusoidal steady-state conditions is described in this paper. Voltages, currents and powers in the primary and secondary windings of the transformer as well as in the high voltage (HV and low voltage (LV lines and in the loads are calculated through that simulator. The apparent powers in the mains, transformer and loads are determined applying Buchholz’s and unified power measurement (UPM formulations in both scalar and vector notations. The effects of the neutral current are especially examined, in order to minimize them, and the optimal wye load distribution is determined by the simulator. The simulator provides the necessary elements of passive reactive and unbalanced compensators that optimize the 4WD transformer operation too. Those compensators are determined for each load, and they can be separately selected and included in the simulation process or not. An application example is finally used to step by step explain how the simulator runs.

  5. Sinusoidal Wave Estimation Using Photogrammetry and Short Video Sequences

    Directory of Open Access Journals (Sweden)

    Ewelina Rupnik

    2015-12-01

    Full Text Available The objective of the work is to model the shape of the sinusoidal shape of regular water waves generated in a laboratory flume. The waves are traveling in time and render a smooth surface, with no white caps or foam. Two methods are proposed, treating the water as a diffuse and specular surface, respectively. In either case, the water is presumed to take the shape of a traveling sine wave, reducing the task of the 3D reconstruction to resolve the wave parameters. The first conceived method performs the modeling part purely in 3D space. Having triangulated the points in a separate phase via bundle adjustment, a sine wave is fitted into the data in a least squares manner. The second method presents a more complete approach for the entire calculation workflow beginning in the image space. The water is perceived as a specular surface, and the traveling specularities are the only observations visible to the  cameras, observations that are notably single image. The depth ambiguity is removed given additional constraints encoded within the law of reflection and the modeled parametric surface. The observation and constraint equations compose a single system of equations that is solved with the method of least squares adjustment. The devised approaches are validated against the data coming from a capacitive level sensor and on physical targets floating on the surface. The outcomes agree to a high degree.

  6. SECs (Sinusoidal Endothelial Cells), Liver Microenvironment, and Fibrosis

    Science.gov (United States)

    Natarajan, Vaishaali; Harris, Edward N.

    2017-01-01

    Liver fibrosis is a wound-healing response to chronic liver injury such as alcoholic/nonalcoholic fatty liver disease and viral hepatitis with no FDA-approved treatments. Liver fibrosis results in a continual accumulation of extracellular matrix (ECM) proteins and paves the way for replacement of parenchyma with nonfunctional scar tissue. The fibrotic condition results in drastic changes in the local mechanical, chemical, and biological microenvironment of the tissue. Liver parenchyma is supported by an efficient network of vasculature lined by liver sinusoidal endothelial cells (LSECs). These nonparenchymal cells are highly specialized resident endothelial cell type with characteristic morphological and functional features. Alterations in LSECs phenotype including lack of LSEC fenestration, capillarization, and formation of an organized basement membrane have been shown to precede fibrosis and promote hepatic stellate cell activation. Here, we review the interplay of LSECs with the dynamic changes in the fibrotic liver microenvironment such as matrix rigidity, altered ECM protein profile, and cell-cell interactions to provide insight into the pivotal changes in LSEC physiology and the extent to which it mediates the progression of liver fibrosis. Establishing the molecular aspects of LSECs in the light of fibrotic microenvironment is valuable towards development of novel therapeutic and diagnostic targets of liver fibrosis. PMID:28293634

  7. Nonlinear dynamics of a sliding beam on two supports under sinusoidal excitation

    Indian Academy of Sciences (India)

    R J Somnay; R A Ibrahim

    2006-08-01

    This study deals with the nonlinear dynamics associated with large deformation of a beam sliding on two-knife edge supports under external excitation. The beam is referred to as a Gospodnetic–Frisch-Fay beam, after the researchers who reported its static deformation in closed form. The freedom of the beam to slide on its supports imparts a nonlinear characteristic to the force-deflection response. The restoring elastic force of the beam possesses characteristics similar to those of the roll-restoring moment of ships. The Gospodnetic–Frisch-Fay exact solution is given in terms of elliptic functions. A curve fit of the exact solution up to eleventh-order is constructed to establish the governing equation of motion under external excitation. The dynamic stability of the unperturbed beam is examined for the damped and undamped cases. The undamped case reveals periodic orbits and one homoclinic orbit depending on the value of the initial conditions. The response to a sinusoidal excitation at a frequency below the linear natural frequency is numerically estimated for different excitation amplitude and different values of initial conditions covered by the area of the homoclinic orbit. The safe basins of attraction are plotted for different values of excitation amplitude. It is found that the safe region of operation is reduced as the excitation amplitude increases.

  8. A Robust Hash Function Using Cross-Coupled Chaotic Maps with Absolute-Valued Sinusoidal Nonlinearity

    Directory of Open Access Journals (Sweden)

    Wimol San-Um

    2016-01-01

    Full Text Available This paper presents a compact and effective chaos-based keyed hash function implemented by a cross-coupled topology of chaotic maps, which employs absolute-value of sinusoidal nonlinearity, and offers robust chaotic regions over broad parameter spaces with high degree of randomness through chaoticity measurements using the Lyapunov exponent. Hash function operations involve an initial stage when the chaotic map accepts initial conditions and a hashing stage that accepts input messages and generates the alterable-length hash values. Hashing performances are evaluated in terms of original message condition changes, statistical analyses, and collision analyses. The results of hashing performances show that the mean changed probabilities are very close to 50%, and the mean number of bit changes is also close to a half of hash value lengths. The collision tests reveal the mean absolute difference of each character values for the hash values of 128, 160 and 256 bits are close to the ideal value of 85.43. The proposed keyed hash function enhances the collision resistance, comparing to MD5 and SHA1, and the other complicated chaos-based approaches. An implementation of hash function Android application is demonstrated.

  9. Orientation During Initial Learning and Subsequent Discrimination of Faces

    Science.gov (United States)

    Cohen, Malcolm M.; Holton, Emily M. (Technical Monitor)

    1997-01-01

    Discrimination of facial features degrades with stimulus rotation (e.g., the "Margaret Thatcher" effect). Thirty-two observers learned to discriminate between two upright, or two inverted, faces. Images, erect and rotated by +/-45deg, +/-90deg, +/-135deg and 180deg about the line of sight, were presented on a computer screen. Initial discriminative reaction times increased with stimulus rotation only for observers who learned the upright faces. Orientation during learning is critical in identifying faces subsequently seen at different orientations.

  10. The family of Deg/HtrA proteases in plants

    Directory of Open Access Journals (Sweden)

    Schuhmann Holger

    2012-04-01

    Full Text Available Abstract Background The Deg/HtrA family of ATP-independent serine endopeptidases is present in nearly all organisms from bacteria to human and vascular plants. In recent years, multiple deg/htrA protease genes were identified in various plant genomes. During genome annotations most proteases were named according to the order of discovery, hence the same names were sometimes given to different types of Deg/HtrA enzymes in different plant species. This can easily lead to false inference of individual protease functions based solely on a shared name. Therefore, the existing names and classification of these proteolytic enzymes does not meet our current needs and a phylogeny-based standardized nomenclature is required. Results Using phylogenetic and domain arrangement analysis, we improved the nomenclature of the Deg/HtrA protease family, standardized protease names based on their well-established nomenclature in Arabidopsis thaliana, and clarified the evolutionary relationship between orthologous enzymes from various photosynthetic organisms across several divergent systematic groups, including dicots, a monocot, a moss and a green alga. Furthermore, we identified a “core set” of eight proteases shared by all organisms examined here that might provide all the proteolytic potential of Deg/HtrA proteases necessary for a hypothetical plant cell. Conclusions In our proposed nomenclature, the evolutionarily closest orthologs have the same protease name, simplifying scientific communication when comparing different plant species and allowing for more reliable inference of protease functions. Further, we proposed that the high number of Deg/HtrA proteases in plants is mainly due to gene duplications unique to the respective organism.

  11. SCALABLE PERCEPTUAL AUDIO REPRESENTATION WITH AN ADAPTIVE THREE TIME-SCALE SINUSOIDAL SIGNAL MODEL

    Institute of Scientific and Technical Information of China (English)

    Al-Moussawy Raed; Yin Junxun; Song Shaopeng

    2004-01-01

    This work is concerned with the development and optimization of a signal model for scalable perceptual audio coding at low bit rates. A complementary two-part signal model consisting of Sines plus Noise (SN) is described. The paper presents essentially a fundamental enhancement to the sinusoidal modeling component. The enhancement involves an audio signal scheme based on carrying out overlap-add sinusoidal modeling at three successive time scales,large, medium, and small. The sinusoidal modeling is done in an analysis-by-synthesis overlapadd manner across the three scales by using a psychoacoustically weighted matching pursuits.The sinusoidal modeling residual at the first scale is passed to the smaller scales to allow for the modeling of various signal features at appropriate resolutions. This approach greatly helps to correct the pre-echo inherent in the sinusoidal model. This improves the perceptual audio quality upon our previous work of sinusoidal modeling while using the same number of sinusoids. The most obvious application for the SN model is in scalable, high fidelity audio coding and signal modification.

  12. Full-Band Quasi-Harmonic Analysis and Synthesis of Musical Instrument Sounds with Adaptive Sinusoids

    Directory of Open Access Journals (Sweden)

    Marcelo Caetano

    2016-05-01

    Full Text Available Sinusoids are widely used to represent the oscillatory modes of musical instrument sounds in both analysis and synthesis. However, musical instrument sounds feature transients and instrumental noise that are poorly modeled with quasi-stationary sinusoids, requiring spectral decomposition and further dedicated modeling. In this work, we propose a full-band representation that fits sinusoids across the entire spectrum. We use the extended adaptive Quasi-Harmonic Model (eaQHM to iteratively estimate amplitude- and frequency-modulated (AM–FM sinusoids able to capture challenging features such as sharp attacks, transients, and instrumental noise. We use the signal-to-reconstruction-error ratio (SRER as the objective measure for the analysis and synthesis of 89 musical instrument sounds from different instrumental families. We compare against quasi-stationary sinusoids and exponentially damped sinusoids. First, we show that the SRER increases with adaptation in eaQHM. Then, we show that full-band modeling with eaQHM captures partials at the higher frequency end of the spectrum that are neglected by spectral decomposition. Finally, we demonstrate that a frame size equal to three periods of the fundamental frequency results in the highest SRER with AM–FM sinusoids from eaQHM. A listening test confirmed that the musical instrument sounds resynthesized from full-band analysis with eaQHM are virtually perceptually indistinguishable from the original recordings.

  13. Dynamic changes of capillarization and peri-sinusoid fibrosis in alcoholic liver diseases

    Institute of Scientific and Technical Information of China (English)

    Guang-Fu Xu; Xin-Yue Wang; Gui-Ling Ge; Peng-Tao Li; Xu Jia; De-Lu Tian; Liang-Duo Jiang; Jin-Xiang Yang

    2004-01-01

    AIM: To investigate the dynamic changes of capillarization and peri-sinusoid fibrosis in an alcoholic liver disease model induced by a new method.METHODS: Male SD rats were randomly divided into 6 groups, namely normal, 4 d, 2 w, 4 w, 9 w and 11 w groups.The animals were fed with a mixture of alcohol for designated days and then decollated, and their livers were harvested to examine the pathological changes of hepatocytes, hepatic stellate cells, sinusoidal endothelial cells, sinusoid, peri-sinusoid. The generation of three kinds of extra cellular matrix was also observed.RESULTS: The injury of hepatocytes became severer as modeling going on. Under electronic microscope, fatty vesicles and swollen mitochondria in hepatocytes, activated hepatic stellate cells with fibrils could been seen near or around it. Fenestrae of sinusoidal endothelial cells were decreased or disappeared, sinusoidal basement was formed.Under light microscopy typical peri-sinusoid fibrosis, gridding-like fibrosis, broaden portal areas, hepatocyte's fatty and balloon denaturation, iron sediment, dot necrosis,congregated lymphatic cells and leukocytes were observed.Type Ⅰ collagen showed an increasing trend as modeling going on, slightly recovered when modeling stopped for 2 weeks. Meanwhile, type Ⅳ collagen decreased rapidly when modeling began and recovered after modeling stopped for 2 weeks. Laminin increased as soon as modeling began and did not recover when modeling stopped for 2 weeks.CONCLUSION: The pathological changes of the model were similar to that of human ALD, but mild in degree. It had typical peri-sinusoid fibrosis; however, capillarization seemed to be instable. It may be related with the reduction of type Ⅳ collagen in the basement of sinusoid during modeling.

  14. An automated system for measuring parameters of nematode sinusoidal movement

    Directory of Open Access Journals (Sweden)

    Stirbl Robert C

    2005-02-01

    Full Text Available Abstract Background Nematode sinusoidal movement has been used as a phenotype in many studies of C. elegans development, behavior and physiology. A thorough understanding of the ways in which genes control these aspects of biology depends, in part, on the accuracy of phenotypic analysis. While worms that move poorly are relatively easy to describe, description of hyperactive movement and movement modulation presents more of a challenge. An enhanced capability to analyze all the complexities of nematode movement will thus help our understanding of how genes control behavior. Results We have developed a user-friendly system to analyze nematode movement in an automated and quantitative manner. In this system nematodes are automatically recognized and a computer-controlled microscope stage ensures that the nematode is kept within the camera field of view while video images from the camera are stored on videotape. In a second step, the images from the videotapes are processed to recognize the worm and to extract its changing position and posture over time. From this information, a variety of movement parameters are calculated. These parameters include the velocity of the worm's centroid, the velocity of the worm along its track, the extent and frequency of body bending, the amplitude and wavelength of the sinusoidal movement, and the propagation of the contraction wave along the body. The length of the worm is also determined and used to normalize the amplitude and wavelength measurements. To demonstrate the utility of this system, we report here a comparison of movement parameters for a small set of mutants affecting the Go/Gq mediated signaling network that controls acetylcholine release at the neuromuscular junction. The system allows comparison of distinct genotypes that affect movement similarly (activation of Gq-alpha versus loss of Go-alpha function, as well as of different mutant alleles at a single locus (null and dominant negative alleles

  15. Limiting Global Warming to 2 deg C and Beyond

    Science.gov (United States)

    Lea, D. W.

    2011-12-01

    This presentation addresses the question of how feasible is it to limit global warming to a specific temperature rise, whether 1.5, 2 or 3 deg C. Inherent in the idea of limiting global warming to a specific temperature level is the notion that future GHG emissions will be subject to a top-down international agreement. In the post-Copenhagen era, however, such an agreement is unlikely, and a bottoms-up approach of national pledges will likely have to serve as a surrogate for achieving emissions reduction. In this case, an additional question is what temperature targets are realistic under scenarios that are bounded by achievable national pledges as opposed to binding mandates. The question of feasibility depends largely on future emission pathways of CO2, other GHGs, black carbon and aerosols. Those pathways depend on many societal, technological and economic factors, but it is likely that the ultimate limiting factor is the maximum possible rate of absolute emission reduction. That rate is limited by how rapidly energy infrastructure can be turned over. Most studies suggest that an absolute emission reduction rate of 3.5% is the highest rate achievable. Climate sensitivity and the current cooling effect of aerosols and earth system responses such as the rate of ocean heat uptake and carbon cycle feedbacks determine how a specific emissions pathway translates into probable climate change. A useful framework for CO2 alone is provided by the newly emerging paradigm of cumulative emissions, which holds that peak temperature can be largely predicted by the total amount of carbon emitted, regardless of pathway. Most studies suggest that 1 Tt of cumulative carbon is equivalent to ~2 deg of peak warming. A consideration of these factors suggests that limiting warming to 1.5 deg C is no longer possible under any feasible economic scenario. For one, currently emitted GHGs are equivalent to a ~1.3 deg C warming commitment. This leaves very little room for future emissions

  16. STRUCTURAL 3D MONITORING USING A NEW SINUSOIDAL FITTING ADJUSTMENT

    Directory of Open Access Journals (Sweden)

    I. Detchev

    2016-06-01

    Full Text Available Digital photogrammetric systems combined with image processing techniques have been used for structural monitoring purposes for more than a decade. For applications requiring sub-millimetre level precision, the use of off-the-shelf DSLR cameras is a suitable choice, especially when the low cost of the involved sensors is a priority. The disadvantage in the use of entry level DSLRs is that there is a trade-off between frame rate and burst rate – a high frame rate is either not available or it cannot be sustained long enough. This problem must be overcome when monitoring a structural element undergoing a dynamic test, where a range of loads are cycled through multiple times a second. In order to estimate deflections during such a scenario, this paper proposes a new least-squares adjustment for sinusoidal fitting. The new technique is capable of processing multiple back-to-back bursts of data within the same adjustment, which synthetically increases the de-facto temporal resolution of the system. The paper describes a beam deformation test done in a structures laboratory. The experimental results were assessed in terms of both their precision and accuracy. The new method increased the effective sampling frequency three-fold, which improved the standard deviations of the estimated parameters with up to two orders of magnitude. A residual RMSE as low as 30 μm was attained, and likewise the RMSE of the computed amplitudes between the photogrammetric system and the control laser transducers was as small as 34 μm.

  17. Structural 3d Monitoring Using a New Sinusoidal Fitting Adjustment

    Science.gov (United States)

    Detchev, I.; Habib, A.; Lichti, D.; El-Badry, M.

    2016-06-01

    Digital photogrammetric systems combined with image processing techniques have been used for structural monitoring purposes for more than a decade. For applications requiring sub-millimetre level precision, the use of off-the-shelf DSLR cameras is a suitable choice, especially when the low cost of the involved sensors is a priority. The disadvantage in the use of entry level DSLRs is that there is a trade-off between frame rate and burst rate - a high frame rate is either not available or it cannot be sustained long enough. This problem must be overcome when monitoring a structural element undergoing a dynamic test, where a range of loads are cycled through multiple times a second. In order to estimate deflections during such a scenario, this paper proposes a new least-squares adjustment for sinusoidal fitting. The new technique is capable of processing multiple back-to-back bursts of data within the same adjustment, which synthetically increases the de-facto temporal resolution of the system. The paper describes a beam deformation test done in a structures laboratory. The experimental results were assessed in terms of both their precision and accuracy. The new method increased the effective sampling frequency three-fold, which improved the standard deviations of the estimated parameters with up to two orders of magnitude. A residual RMSE as low as 30 μm was attained, and likewise the RMSE of the computed amplitudes between the photogrammetric system and the control laser transducers was as small as 34 μm.

  18. High resolution DAS via sinusoidal frequency scan OFDR (SFS-OFDR).

    Science.gov (United States)

    Leviatan, Eyal; Eyal, Avishay

    2015-12-28

    There are many advantages to using direct frequency modulation for OFDR based DAS. However, achieving sufficiently linear scan via direct frequency modulation is challenging and poses limits on the scan parameters. A novel method for analyzing sinusoidal frequency modulated light is presented and demonstrated for both static and dynamic sensing. SFS-OFDR projects the measured signal onto appropriate sinusoidal phase terms to obtain spatial information. Thus, by using SFS-OFDR on sinusoidal modulated light it is possible to make use of the many advantages offered by direct frequency modulation without the limitations posed by the linearity requirement.

  19. Feedforward and Feedback Optimal Control for Linear Systems with Sinusoidal Disturbances

    Institute of Scientific and Technical Information of China (English)

    唐功友

    2001-01-01

    The linear systems affected by additive external sinusoidal disturbances is studied. he problem is to damp this forced oscillation in an optimal fashion. The main result of this paper is a new design approach is proposed of realizable feedforward and feedback optimal control law for a linear timeinvariant system with sinusoidal disturbances. The algorithm of solving the optimal control law is given. It is shown that the control law is easily realized and is robust with respect to errors produced by the external sinusoidal disturbances through simulation results.

  20. Tropospheric ozone over a tropical Atlantic station in the Northern Hemisphere: Paramaribo, Surinam (6 deg N, 55 deg W)

    Energy Technology Data Exchange (ETDEWEB)

    Peters, W.; Krol, M.C. [Inst. for Marine and Atmospheric Research Utrecht (Netherlands); Fortuin, J.P.F.; Kelder, H.M. [Koninklijke Nederlandse Meteorologische Dienst, De Bilt (Netherlands); Thompson, A.M. [Goddard Space Flight Center, NASA, Greenbelt, MD (United States); Becker, C.R. [Meteorologische Dienst Suriname, Paramaribo (Suriname); Lelieveld, J.; Crutzen, P.J. [Max Planck Inst. fuer Chemie, Mainz (Germany)

    2004-02-01

    We present an analysis of 2.5 yr of weekly ozone soundings conducted at a new monitoring station in Paramaribo, Surinam (6 deg N, 55 deg W). This is currently one of only three ozone sounding stations in the Northern Hemisphere (NH) tropics, and the only one in the equatorial Atlantic region. Paramaribo is part of the Southern Hemisphere Additional Ozone Sounding program (SHADOZ). Owing to its position close to the equator, the inter-tropical convergence zone (ITCZ) passes over Paramaribo twice per year, which results in a semi-annual seasonality of many parameters including relative humidity and ozone. The dataset from Paramaribo is used to: (1) evaluate the ozone variability relative to precipitation, atmospheric circulation patterns and biomass burning; (2) contrast ozone at the NH equatorial Atlantic with that at nearby Southern Hemisphere (SH) stations Natal (6 deg S, 35 deg W) and Ascension (8 deg S, 14 deg W); (3) compare the seasonality of tropospheric ozone with a satellite-derived ozone product: tropical tropospheric ozone columns from the modified residual method (MR-TTOC). We find that Paramaribo is a distinctly Atlantic station. Despite its position north of the equator, it resembles nearby SH stations during most of the year. Transport patterns in the lower and middle troposphere during February and March differ from SH stations, which leads to a seasonality of ozone with two maxima. MR-TTOC over Paramaribo does not match the observed seasonality of ozone due to the use of a SH ozone sonde climatology in the MR method. The Paramaribo ozone record is used to suggest an improvement for Northern Hemisphere MR-TTOC retrievals. We conclude that station Paramaribo shows unique features in the region, and clearly adds new information to the existing SHADOZ record.

  1. Radio identification of decameter-wave sources. II: The 30degdeg declination interval

    CERN Document Server

    Verkhodanov, O V; Andernach, H; 10.1134/S1990341309010052

    2009-01-01

    This paper is dedicated to the identification of decameter-wave sources of the UTR catalog within declination interval 30degdeg. UTR sources are cross-identified with CATS database catalogs within 40'x40' error boxes. The sources are deblended using the data on the coordinates of the objects and the behavior of their continuum radio spectra. The spectra of 876 sources are derived and fitted by standard analytical functions. Of these sources, 221 objects have straight-line spectra with spectral indices alpha<-1.0. All objects are catalogued and stored in the CATS database.

  2. AC losses in HTS coils for high-frequency and non-sinusoidal currents

    Science.gov (United States)

    de Bruyn, B. J. H.; Jansen, J. W.; Lomonova, E. A.

    2017-09-01

    AC losses in racetrack coils that are wound of YBCO tapes are measured for sinusoidal and non-sinusoidal transport currents with fundamental frequencies up to 1 kHz. An electrical method to measure losses for non-sinusoidal currents is developed for this purpose. The measured losses are compared to the losses calculated by 2D finite element models with power-law material models. The frequency and waveform-dependency of the measured losses are shown and compared to the results of the models over a wide range of frequencies and waveforms. Finally, it is shown that the finite element models can accurately predict AC losses resulting from non-sinusoidal transport currents as are present in highly dynamic motors with AC armature coils.

  3. Sinusoidal wavelength-scanning interferometer with a superluminescent diode for step-profile measurement.

    Science.gov (United States)

    Sasaki, O; Murata, N; Suzuki, T

    2000-09-01

    In sinusoidal phase-modulating interferometry an optical path length (OPD) larger than a wavelength is measured by detection of sinusoidal phase-modulation amplitude Z(b) of the interference signal that is produced by sinusoidal scanning of the wavelength of a light source. A light source with a large scanning width of wavelength is created by use of a superluminescent laser diode for the error in the measured value obtained by Z(b) to be smaller than half of the central wavelength. In this situation the measured value can be combined with a fractional value of the OPD obtained from the conventional phase of the interference signal. A sinusoidal wavelength-scanning interferometer with the light source measures an OPD over a few tens of micrometers with a high accuracy of a few nanometers.

  4. Optimization for sinusoidal profiles in surface relief gratings recorded on photoresist

    Indian Academy of Sciences (India)

    Sanjiva Kumar; Amrita Debnath; R B Tokas; K Divakar Rao; D V Udupa; N K Sahoo

    2014-02-01

    The formations of sinusoidal surface relief structures recorded in positive photoresist (Allresist AR-P 3120) have been studied and optimized for different recording parameters of gratings with spatial frequency of∼1200 grooves/mm.Astable sinusoidal pattern generated using a two-beam laser interferometric technique was recorded in thin films of positive photoresist deposited on glass substrates. Several gratings were generated by varying the exposure time of interference pattern and time of chemical development of exposed media. Time duration of exposure for 90 s and chemical development for 15 s were observed to be optimum for the translation of the sinusoidal interference pattern into nearly-sinusoidal profiled grooves in the gratings for a developer AR-300-26 of dilution of 2:1 (developer:de-ionized water).

  5. Multiple Description Spherical Quantization of Sinusoidal Parameters with Repetition Coding of the Amplitudes

    DEFF Research Database (Denmark)

    Jensen, Jesper Rindom; Christensen, Mads Græsbøll; Larsen, Morten Holm

    2009-01-01

    Recently, multiple description spherical trellis-coded quantization (MDSTCQ) for quantization of sinusoidal parameters was proposed, which suffered from a suboptimal implementation. Therefore, we propose the multiple description spherical quantization with repetition coding of the amplitudes (MDS...

  6. Sinusoidal Phase-Modulating Fabry-Perot Interferometer for Angular Displacement Measurement

    Institute of Scientific and Technical Information of China (English)

    Caini Zhang; Xiangzhao Wang

    2003-01-01

    In this paper, a sinusoidal phase-modulating Fabry-Perot interferometer is proposed to measure angular displacement.The usefulness of the interferometer is demonstrated by simulations and experiments.

  7. Sinusoidal Phase-Modulating Fabry-Perot Interferometer for Angular Displacement Measurement

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    In this paper, a sinusoidal phase-modulating Fabry-Perot interferometer is proposed to measure angular displacement. The usefulness of the interferometer is demonstrated by simulations and experiments.

  8. A metabonomic evaluation of the monocrotaline-induced sinusoidal obstruction syndrome (SOS) in rats

    Energy Technology Data Exchange (ETDEWEB)

    Conotte, R.; Colet, J.-M., E-mail: jean-marie.colet@umons.ac.be

    2014-04-15

    The main curative treatment of colorectal cancer remains the surgery. However, when metastases are suspected, surgery is followed by a preventive chemotherapy using oxaliplatin which, unfortunately, may cause liver sinusoidal obstruction syndrome (SOS). Such hepatic damage is barely detected during or after chemotherapy due to a lack of effective diagnostic procedures, but liver biopsy. The primary objective of the present study was to identify potential early diagnosis biomarkers of SOS using a metabonomic approach. SOS was induced in rats by monocrotaline, a prototypical toxic substance. {sup 1}H NMR spectroscopy analysis of urine samples collected from rats treated with monocrotaline showed significant metabolic changes as compared to controls. During a first phase, cellular protective mechanisms such as an increased synthesis of GSH (reduced taurine) and the recruitment of cell osmolytes in the liver (betaine) were seen. In the second phase, the disturbance of the urea cycle (increased ornithine and urea reduction) leading to the depletion of NO, the alteration in the GSH synthesis (increased creatine and GSH precursors (glutamate, dimethylglycine and sarcosine)), and the liver necrosis (decrease taurine and increase creatine) all indicate the development of SOS. - Highlights: • Urine metabonomic profiles of SOS have been identified. • Urine osmoprotectants and anti-oxidants indicated an initial liver protection. • Liver necrosis was demonstrated by increased urine levels of taurine and creatine. • NO depletion was suggested by changes in ornithine and urea.

  9. Improvement of stability of sinusoidally driven atmospheric pressure plasma jet using auxiliary bias voltage

    Directory of Open Access Journals (Sweden)

    Hyun-Jin Kim

    2015-12-01

    Full Text Available In this study, we have proposed the auxiliary bias pulse scheme to improve the stability of atmospheric pressure plasma jets driven by an AC sinusoidal waveform excitation source. The stability of discharges can be significantly improved by the compensation of irregular variation in memory voltage due to the effect of auxiliary bias pulse. From the parametric study, such as the width, voltage, and onset time of auxiliary bias pulse, it has been demonstrated that the auxiliary bias pulse plays a significant role in suppressing the irregular discharges caused by the irregular variation in memory voltage and stable discharge can be initiated with the termination of the auxiliary bias pulse. As a result of further investigating the effects of the auxiliary pulse scheme on the jet stability under various process conditions such as the distance between the jet head and the counter electrode, and carrier gas flow, the jet stability can be improved by adjusting the amplitude and number of the bias pulse depending on the variations in the process conditions.

  10. Comparison of atmospheric air plasmas excited by high-voltage nanosecond pulsed discharge and sinusoidal alternating current discharge

    Science.gov (United States)

    Zhang, Shuai; Wang, Wen-chun; Jiang, Peng-chao; Yang, De-zheng; Jia, Li; Wang, Sen

    2013-10-01

    In this paper, atmospheric pressure air discharge plasma in quartz tube is excited by 15 ns high-voltage nanosecond pulsed discharge (HVNPD) and sinusoidal alternating current discharge (SACD), respectively, and a comparison study of these two kinds of discharges is made through visual imaging, electrical characterization, optical detection of active species, and plasma gas temperature. The peak voltage of the power supplies is kept at 16 kV while the pulse repetition rate of nanosecond pulse power supply is 100 Hz, and the frequency of sinusoidal power supply is 10 kHz. Results show that the HVNPD is uniform while the SACD presents filamentary mode. For exciting the same cycles of discharge, the average energy consumption in HVNPD is about 1/13 of the SACD. However, the chemical active species generated by the HVNPD is about 2-9 times than that excited by the SACD. Meanwhile, the rotational and vibrational temperatures have been obtained via fitting the simulated spectrum of N2 (C3Πu → B3Πg, 0-2) with the measured one, and the results show that the plasma gas temperature in the HVNPD remains close to room temperature whereas the plasma gas temperature in the SACD is about 200 K higher than that in HVNPD in the initial phase and continually increases as discharge exposure time goes on.

  11. Sinusoidal obstruction syndrome (veno-occlusive disease in a patient receiving bevacizumab for metastatic colorectal cancer: a case report

    Directory of Open Access Journals (Sweden)

    Agarwal Vijay

    2008-07-01

    Full Text Available Abstract Introduction We present the case of a patient with colon cancer who, while receiving bevacizumab, developed sinusoidal obstruction syndrome (veno-occlusive disease (SOSVOD. Certain antitumour agents such as 6-mercaptopurine and 6-thioguanine have also been reported to initiate hepatic SOSVOD in isolated cases. There have been no reports so far correlating bevacizumab with SOSVOD. Case presentation A 77-year-old man was being treated with oxaliplatin and a modified de Gramont regimen of 5-fluorouracil for metastatic colon cancer. Bevacizumab (7.5 mg/kg was added from the seventh cycle onwards. Protracted neutropenia and thrombocytopenia led to discontinuation of oxaliplatin after the ninth cycle. A computed tomography scan showed complete response and bevacizumab was continued for another 3 months, after which time the patient developed right hypochondrial pain, transudative ascites, splenomegaly and abnormal liver function tests. Upper gastrointestinal endoscopy showed oesophageal varices. Liver biopsy showed features considered to be consistent with SOSVOD. Bevacizumab was stopped and a policy of watchful waiting was adopted. He tolerated the acute damage to his liver and subsequently the ascites resolved and liver function tests normalised. Conclusion We need to be aware that bevacizumab can cause sinusoidal obstruction syndrome (veno-occlusive disease and that the occurrence of ascites should not be attributed to progressive disease without appropriate evaluation.

  12. Ultrastructural changes in hepatic sinusoidal endothelial cells acutely exposed to colloidal iron.

    Science.gov (United States)

    Bassett, Mark L; Dahlstrom, Jane E; Taylor, Matthew C; Koina, Mark E; Maxwell, Lesley; Francis, Douglas; Jain, Sanjiv; McLean, Allan J

    2003-07-01

    Hepatic sinusoidal endothelial cells form an important interface between the vascular system, represented by the sinusoids, and the space of Disse that surrounds the hepatocyte microvilli. This study aimed to assess the light microscopic and ultrastructural effects of acute exposure of hepatic sinusoidal endothelial cells to colloidal iron by injection of rats with iron polymaltose. Eight minutes after a single intravenous injection of iron polymaltose sinusoidal endothelial cells showed defenestration, and thickening and layering as assessed by transmission electron microscopy. Kupffer cells and stellate cells appeared activated. These changes were not observed in control animals, experiments using equivalent doses of maltose, or experiments using colloidal carbon except for Kupffer cell activation due to colloidal carbon. No significant light microscopic changes were seen in study or control animals. The findings indicate that acute exposure to colloidal iron causes changes in hepatic sinusoidal endothelial cells, stellate cells and Kupffer cells. This may be the result of a direct toxic effect of iron or increased production of reactive oxygen species. These observations suggest a possible mechanism for defenestration of sinusoidal endothelial cells in ageing and in disease states.

  13. Carbon monoxide: an endogenous modulator of sinusoidal tone in the perfused rat liver.

    Science.gov (United States)

    Suematsu, M; Goda, N; Sano, T; Kashiwagi, S; Egawa, T; Shinoda, Y; Ishimura, Y

    1995-11-01

    Heme oxygenase is a heme-oxidizing enzyme which generates biliverdin and carbon monoxide (CO). The present study was designed to elucidate whether CO endogenously produced by this enzyme serves as an active vasorelaxant in the hepatic microcirculation. Microvasculature of the isolated perfused rat liver was visualized by dual-color digital microfluorography to alternately monitor sinusoidal lining and fat-storing Ito cells. In the control liver, the CO flux in the venous effluent ranged at 0.7 nmol/min per gram of liver. Administration of a heme oxygenase inhibitor zinc protoporphyrin IX (1 microM) eliminated the baseline CO generation, and the vascular resistance exhibited a 30% elevation concurrent with discrete patterns of constriction in sinusoids and reduction of the sinusoidal perfusion velocity. The major sites of the constriction corresponded to local sinusoidal segments colocalized with Ito cell which were identified by imaging their vitamin A autofluorescence. The increase in the vascular resistance and sinusoidal constriction were attenuated significantly by adding CO (1 microM) or a cGMP analogue 8-bromo-cGMP (1 microM) in the perfusate. From these findings, we propose that CO can function as an endogenous modulator of hepatic sinusoidal perfusion through a relaxing mechanism involving Ito cells.

  14. Embrittlement of reduced-activation ferritic/martensitic steels irradiated in HFIR at 300 deg. C and 400 deg. C

    Energy Technology Data Exchange (ETDEWEB)

    Klueh, R.L. E-mail: ku2@ornl.gov; Sokolov, M.A.; Shiba, K.; Miwa, Y.; Robertson, J.P

    2000-12-01

    Miniature tensile and Charpy specimens of four ferritic/martensitic steels were irradiated at 300 deg. C and 400 deg. C in the high flux isotope reactor (HFIR) to a maximum dose of {approx}12 dpa. The steels were standard F82H (F82H-Std), a modified F82H (F82H-Mod), ORNL 9Cr-2WVTa, and 9Cr-2WVTa-2Ni, the 9Cr-2WVTa containing 2% Ni to produce helium by (n,{alpha}) reactions with thermal neutrons. More helium was produced in the F82H-Std than the F82H-Mod because of the presence of boron. Irradiation embrittlement in the form of an increase in the ductile-brittle transition temperature ({delta}DBTT) and a decrease in the upper-shelf energy (USE) occurred for all the steels. The two F82H steels had similar {delta}DBTTs after irradiation at 300 deg. C, but after irradiation at 400 deg. C, the {delta}DBTT for F82H-Std was less than for F82H-Mod. Under these irradiation conditions, little effect of the extra helium in the F82H-Std could be discerned. Less embrittlement was observed for 9Cr-2WVTa steel irradiated at 400 deg. C than for the two F82H steels. The 9Cr-2WVTa-2Ni steel with {approx}115 appm He had a larger {delta}DBTT than the 9Cr-2WVTa with {approx}5 appm He, indicating a possible helium effect.

  15. Modello metodologico per il monitoraggio degli incidenti stradali in Trentino

    Directory of Open Access Journals (Sweden)

    P. Fateh-Moghadam

    2003-05-01

    Full Text Available

    Obiettivi: realizzazione di un’infrastruttura informatica, per l’unificazione tempestiva dei flussi sugli incidenti stradali (ISTAT-ACI e sanitari con la georeferenziazione degli eventi a partire dall’anno 2000.

    Materiali e Metodi: dall’archivio di Trentino emergenza sono stati estratti gli interventi per incidente stradale selezionando la combinazione: descrizione patologica: “traumatismi”, tipologia luogo: “strada”, tipologia incidente. Dai dati di ogni Pronto soccorso è stato costruito un archivio unico contenente il totale degli accessi e sono stati estratti gli accessi per “incidente stradale” e quelli per lesioni accidentali in generale. Dall’archivio SDO si sono selezionati sia i ricoveri con il criterio “3” alla variabile mtraav (=incidente stradale che quelli per traumatismi.

    Nell’ambito del progetto “Metodi informatici predittivi per la mitigazione del rischio da incidenti stradali” (Mitris, finanziato dal Ministero della Salute, è stata realizzata l’immissione tramite interfaccia internet o decodifica automatica dei verbali informatizzati delle Forze dell’ordine, e la contestuale realizzazione di un interfaccia WebGIS
    in grado di visualizzare la localizzazione degli incidenti stradali.

    Risultati: tramite la combinazione “data nascita”,
    “data incidente”, “sesso” è stato eseguito un primo collegamento tra gli archivi. Aggiungendo alla data incidente uno o più giorni, è stato costruito un nuovo archivio PS contenente il 97,4% degli eventi raccolti dalle forze dell’Ordine e contenuti nel data base Mitris. Approccio analogo è stato seguito per il linkage con SDO e 118. Tramite interfaccia WebGIS è stata creata una mappa degli incidenti interrogabile on-line, che oltre alla semplice localizzazione riporta dinamica e esiti con possibilità di produrre statistiche e grafici. Il sistema copre attualmente

  16. Immagini dinamiche: appunti per un catalogo degli usi didattici

    Directory of Open Access Journals (Sweden)

    Filippo Bruni

    2013-03-01

    Full Text Available Le immagini dinamiche costituiscono un’importante risorsa per le attività didattiche. A partire da una riflessione storica, si evidenzia in primo luogo l’importanza di un loro uso efficace alla luce della classificazione operata da Clark e Lyons. In secondo luogo si segnalano alcune attività emergenti legate alla documentazione, al digital storytelling e alla formazione degli insegnanti.

  17. Technical Note: Using DEG CPCs at upper tropospheric temperatures

    CERN Document Server

    Wimmer, D; Nieminen, T; Duplissy, J; Ehrhart, S; Almeida, J; Rondo, L; Franchin, A; Kreissl, F; Manninen, H E; Kulmala, M; Curtius, J; Petäjä, T

    2014-01-01

    Over the last few years, several Condensation Particle Counters (CPC) capable of measuring in the sub-3 nm size range have been developed. Here we study the performance of Diethylene glycol (DEG) based CPCs at different temperatures during Cosmics Leaving Outdoor Droplets (CLOUD) measurements at CERN. The data shown here is the first set of verification measurements for sub-3 nm CPCs under upper tropospheric temperatures using atmospherically relevant aerosol particles. To put the results in perspective we calibrated the DEG-CPC at room temperature, resulting in a cut-off diameter of 1.4 nm. All diameters refer to mobility equivalent diameters in this manuscript. At upper tropospheric temperatures between −25 °C and −65 °C, we found cut-off sizes in the range of 2.5 and 2.8 nm. Due to low number concentration after size classification, the cut-off diameters have a high uncertainty (±0.3 nm) associated with them. Operating two laminar flow DEG CPCs with different cut-off sizes together with other aeroso...

  18. Book review. La forma degli animali. Adolf Portmann

    Directory of Open Access Journals (Sweden)

    Manuel Graziani

    2013-09-01

    Full Text Available Nel 1931 il biologo Adolf Portmann era già talmente noto a livello internazionale per le sue ricerche da guadagnarsi la cattedra in zoologia nell'università della sua città natale, Basilea, all'età di appena 34 anni. All'attività di docente universitario ha sempre affiancato un'originale riflessione sul significato delle scienze della vita, imponendosi come una delle figure chiave nel dibattito tra biologia teoretica, estetica e antropologia filosofica. La forma degli animali, la sua opera più celebre, si pone al confine tra varie discipline e conserva un grande interesse ancora oggi che il dialogo tra estetica e biologia si è fatto nuovamente intenso. Pubblicata nel 1948 e in forma ampliata nel 1960 (da cui deriva questa prima edizione italiana a cura di Pietro Conte l'opera rappresenta il frutto più maturo delle sue ricerche "interdisciplinari".Un saggio che nasce dall'insoddisfazione nei confronti dei paradigmi scientifici consolidati e che ripropone l'idea morfologica in biologia sulla scorta del pensiero di J. W. Goethe il quale affermava che "tutto ciò che è deve anche dar cenno di sé e mostrarsi". Adolf Portmann è un convinto sostenitore che dalla forma si possano dedurne le complessive caratteristiche interne ed esterne degli animali. Secondo questa prospettiva la peculiare fisionomia dell'organismo dipende dalla congiunzione delle sue parti e dalle loro reciproche funzioni. Tuttavia l'autore non vede nello studio della forma l'alternativa al funzionalismo quanto, piuttosto, il suo necessario bilanciamento come dichiara nell'introduzione: "… per giungere alla conoscenza della vita animale di strade ce ne sono molte, e tutte possono contribuire ad arricchire la nostra esperienza. Questo lavoro si occupa della forma degli animali e si propone di mettere in luce la peculiare natura dell'aspetto visibile. Ci sono persone che si dedicano allo studio degli animali, conoscono moltissime specie, hanno imparato centinaia di nomi e

  19. Geology of the Delta, Escalante, Price, Richfield and Salina 1 deg x 2 deg NTMS quadrangles, Utah

    Science.gov (United States)

    Thayer, P. A.

    1981-11-01

    The National Uranium Resource Evaluation (NURE) program was established to evaluate domestic uranium resources in the continental United States and to identify areas favorable for uranium exploration. The Grand Junction Office of the Department of Energy is responsible for administering the program. The Savannah River Laboratory (SRL) is responsible for hydrogeochemical and stream-sediment reconnaissance (HSSR) of 3.9 million sq km (1,500,000 mi(2)) in 37 eastern and western states. This document provides geologic and mineral resources reports for the Delta, Escalante, Price, Richfield, and Salina 1 deg x 2 deg National Topographic Map Series quadrangles, Utah. The purpose of these reports is to provide background geologic and mineral resources information to aid in the interpretation of NURE geochemical reconnaissance data. Except for the Escalante Quadrangle, each report is accompanied by a geologic map and a mineral locality map (Plates 1-8, in pocket).

  20. The inhibition of stuttering via the presentation of natural speech and sinusoidal speech analogs.

    Science.gov (United States)

    Saltuklaroglu, Tim; Kalinowski, Joseph

    2006-08-14

    Sensory signals containing speech or gestural (articulatory) information (e.g., choral speech) have repeatedly been found to be highly effective inhibitors of stuttering. Sine wave analogs of speech consist of a trio of changing pure tones representative of formant frequencies. They are otherwise devoid of traditional speech cues, yet have proven to evoke consistent linguistic percepts in listeners. Thus, we investigated the potency of sinusoidal speech for inhibiting stuttering. Ten adults who stutter read while listening to (a) forward-flowing natural speech; (b) forward-flowing sinusoid analogs of natural speech; (c) reversed natural speech; (d) reversed sinusoid analogs of natural speech; and (e) a continuous 1000 Hz pure tone. The levels of stuttering inhibition achieved using the sinusoidal stimuli were potent and not significantly different from those achieved using natural speech (approximately 50% in forward conditions and approximately 25% in the reversed conditions), suggesting that the patterns of undulating pure tones are sufficient to endow sinusoidal sentences with 'quasi-gestural' qualities. These data highlight the sensitivity of a specialized 'phonetic module' for extracting gestural information from sensory stimuli. Stuttering inhibition is thought to occur when perceived gestural information facilitates fluent productions via the engagement of mirror neurons (e.g., in Broca's area), which appear to play a crucial role in our ability to perceive and produce speech.

  1. Electronically Tunable Quadrature Sinusoidal Oscillator with Equal Output Amplitudes during Frequency Tuning Process

    Directory of Open Access Journals (Sweden)

    Den Satipar

    2017-01-01

    Full Text Available A new configuration of voltage-mode quadrature sinusoidal oscillator is proposed. The proposed oscillator employs two voltage differencing current conveyors (VDCCs, two resistors, and two grounded capacitors. In this design, the use of multiple/dual output terminal active building block is not required. The tuning of frequency of oscillation (FO can be done electronically by adjusting the bias current of active device without affecting condition of oscillation (CO. The electronic tuning can be done by controlling the bias current using a digital circuit. The amplitude of two sinusoidal outputs is equal when the frequency of oscillation is tuned. This makes the sinusoidal output voltages meet good total harmonic distortions (THD. Moreover, the proposed circuit can provide the sinusoidal output current with high impedance which is connected to external load or to another circuit without the use of buffer device. To confirm that the oscillator can generate the quadrature sinusoidal output signal, the experimental results using VDCC constructed from commercially available ICs are also included. The experimental results agree well with theoretical anticipation.

  2. Neutrophil adhesion and crawling dynamics on liver sinusoidal endothelial cells under shear flow.

    Science.gov (United States)

    Yang, Hao; Li, Ning; Du, Yu; Tong, Chunfang; Lü, Shouqin; Hu, Jinrong; Zhang, Yan; Long, Mian

    2017-02-01

    Neutrophil (polymorphonuclear leukocyte, PMN) recruitment in the liver sinusoid takes place in almost all liver diseases and contributes to pathogen clearance or tissue damage. While PMN rolling unlikely appears in liver sinusoids and Mac-1 or CD44 is assumed to play respective roles during in vivo local or systematic inflammatory stimulation, the regulating mechanisms of PMN adhesion and crawling dynamics are still unclear from those in vivo studies. Here we developed a two-dimensional in vitro sinusoidal model with primary liver sinusoidal endothelial cells (LSECs) and Kupffer cells (KCs) to investigate TNF-α-induced PMN recruitment under shear flow. Our data demonstrated that LFA-1 dominates the static or shear resistant adhesion of PMNs while Mac-1 decelerates PMN crawling on LSEC monolayer. Any one of LFA-1, Mac-1, and CD44 molecules is not able to work effectively for mediating PMN transmigration across LSEC monolayer. The presence of KCs only affects the randomness of PMN crawling. These findings further the understandings of PMN recruitment under shear flow in liver sinusoids.

  3. Sinusoidal microcirculatory changes after small-for-size liver transplantation in rats.

    Science.gov (United States)

    Li, Junjian; Liang, Liang; Ma, Tao; Yu, Xiazhen; Chen, Wei; Xu, Guodong; Liang, Tingbo

    2010-09-01

    Small-for-size graft injury is characterized by portal venous hypertension and loss of intracellular homeostasis early after transplant. The long-term alteration of sinusoidal microcirculatory hemodynamic state remains unknown. A syngeneic rat orthotopic liver transplantation model was developed using small-for-size grafts (35% of recipient liver weight) or whole grafts (100% of recipient liver weight). Graft survival, portal pressure, liver function, hepatocellular apoptosis as well as morphological changes (by light microscopy and electron microscopy) were assessed. Sinusoidal microcirculatory hemodynamics was examined by intravital fluorescence microscopy. Although portal hypertension lasted only for 1 h after performance of small-for-size liver transplantation, a sustained microcirculatory disturbance was accompanied by dramatic reduction of sinusoidal perfusion rate, elevation of sinusoidal diameter as well as increase in the number of apoptotic hepatocytes during the first 7 days. These resulted in lower survival rate (50% vs. 100%, P = 0.012), higher level of liver function, and more severe morphological changes, which could induce small-for-size syndrome. In conclusion, persistent microcirculatory hemodynamic derangement during the first 7 days after reperfusion as well as transient portal hypertension is significant manifestation after small-for-size liver transplantation. Long-term microcirculation disturbance displayed as decrease of sinusoidal reperfusion area and increase of spread in functional liver mass seems to be the key factor for graft injuries.

  4. Technical Note: Using DEG-CPCs at upper tropospheric temperatures

    Science.gov (United States)

    Wimmer, D.; Lehtipalo, K.; Nieminen, T.; Duplissy, J.; Ehrhart, S.; Almeida, J.; Rondo, L.; Franchin, A.; Kreissl, F.; Bianchi, F.; Manninen, H. E.; Kulmala, M.; Curtius, J.; Petäjä, T.

    2015-07-01

    Over the last few years, several condensation particle counters (CPCs) capable of measuring in the sub-3 nm size range have been developed. Here we study the performance of CPCs based on diethylene glycol (DEG) at different temperatures during Cosmics Leaving OUtdoor Droplets (CLOUD) measurements at CERN. The data shown here are the first set of verification measurements for sub-3 nm CPCs under upper tropospheric temperatures using atmospherically relevant aerosol particles. To put the results in perspective we calibrated the DEG-CPC at room temperature, resulting in a cut-off diameter of 1.4 nm. All diameters refer to mobility equivalent diameters in this paper. At upper tropospheric temperatures ranging from 246.15 K to 207.15 K, we found cut-off sizes relative to a particle size magnifier in the range of 2.5 to 2.8 nm. Due to low number concentration after size classification, the cut-off diameters have a high uncertainty (±0.3 nm) associated with them. Operating two laminar flow DEG-CPCs with different cut-off sizes together with other aerosol instruments, we looked at the growth rates of aerosol population in the CLOUD chamber for particles smaller than 10 nm at different temperatures. A more consistent picture emerged when we normalized the growth rates to a fixed gas-phase sulfuric acid concentration. All of the instruments detected larger growth rates at lower temperatures, and the observed growth rates decreased as a function of temperature, showing a similar trend for all instruments. The theoretical calculations had a similar but much smaller temperature dependency.

  5. Associating Long-term Gamma-ray Variability with the Superorbital Period of LS I + 61 Deg. 303

    Science.gov (United States)

    Ackermann, M.; Ajello, M.; Ballet, J.; Barbiellini, G.; Bastieri, D.; Bellazzini, R.; Bonamente, E.; Brandt, T. J.; Bregeon, J.; Brigida, M.; Bruel, P.; Buehler, R.; Buson, S.; Caliandro, G. A.; Cameron, R. A.; Caraveo, P. A.; Casandjian, J. M.; Ferrara, E. C.; Guiriec, S.; Harding, A. K.; Hays, E.; McEnery, J. E.; Nemmen, R.; Perkins, J. S.; Scargle, J. D.; Troja, E.

    2013-01-01

    Gamma-ray binaries are stellar systems for which the spectral energy distribution (discounting the thermal stellar emission) peaks at high energies. Detected from radio to TeV gamma rays, the gamma-ray binary LS I + 61?303 is highly variable across all frequencies. One aspect of this system's variability is the modulation of its emission with the timescale set by the approx. 26.4960 day orbital period. Here we show that, during the time of our observations, the gamma-ray emission of LS I + 61 deg. 303 also presents a sinusoidal variability consistent with the previously known superorbital period of 1667 days. This modulation is more prominently seen at orbital phases around apastron, whereas it does not introduce a visible change close to periastron. It is also found in the appearance and disappearance of variability at the orbital period in the power spectrum of the data. This behavior could be explained by a quasi-cyclical evolution of the equatorial outflow of the Be companion star, whose features influence the conditions for generating gamma rays. These findings open the possibility to use gamma-ray observations to study the outflows of massive stars in eccentric binary systems.

  6. Mutations suppressing the loss of DegQ function in Bacillus subtilis (natto) poly-γ-glutamate synthesis.

    Science.gov (United States)

    Do, Thi-Huyen; Suzuki, Yuki; Abe, Naoki; Kaneko, Jun; Itoh, Yoshifumi; Kimura, Keitarou

    2011-12-01

    The degQ gene of Bacillus subtilis (natto), encoding a small peptide of 46 amino acids, is essential for the synthesis of extracellular poly-gamma-glutamate (γPGA). To elucidate the role of DegQ in γPGA synthesis, we knocked out the degQ gene in Bacillus subtilis (natto) and screened for suppressor mutations that restored γPGA synthesis in the absence of DegQ. Suppressor mutations were found in degS, the receptor kinase gene of the DegS-DegU two-component system. Recombinant DegS-His(6) mutant proteins were expressed in Escherichia coli cells and subjected to an in vitro phosphorylation assay. Compared with the wild type, mutant DegS-His(6) proteins showed higher levels of autophosphorylation (R208Q, M195I, L248F, and D250N), reduced autodephosphorylation (D250N), reduced phosphatase activity toward DegU, or a reduced ability to stimulate the autodephosphorylation activity of DegU (R208Q, D249G, M195I, L248F, and D250N) and stabilized DegU in the phosphorylated form. These mutant DegS proteins mimic the effect of DegQ on wild-type DegSU in vitro. Interestingly, DegQ stabilizes phosphorylated DegS only in the presence of DegU, indicating a complex interaction of these three proteins.

  7. Mutations Suppressing the Loss of DegQ Function in Bacillus subtilis (natto) Poly-γ-Glutamate Synthesis ▿ †

    Science.gov (United States)

    Do, Thi-Huyen; Suzuki, Yuki; Abe, Naoki; Kaneko, Jun; Itoh, Yoshifumi; Kimura, Keitarou

    2011-01-01

    The degQ gene of Bacillus subtilis (natto), encoding a small peptide of 46 amino acids, is essential for the synthesis of extracellular poly-gamma-glutamate (γPGA). To elucidate the role of DegQ in γPGA synthesis, we knocked out the degQ gene in Bacillus subtilis (natto) and screened for suppressor mutations that restored γPGA synthesis in the absence of DegQ. Suppressor mutations were found in degS, the receptor kinase gene of the DegS-DegU two-component system. Recombinant DegS-His6 mutant proteins were expressed in Escherichia coli cells and subjected to an in vitro phosphorylation assay. Compared with the wild type, mutant DegS-His6 proteins showed higher levels of autophosphorylation (R208Q, M195I, L248F, and D250N), reduced autodephosphorylation (D250N), reduced phosphatase activity toward DegU, or a reduced ability to stimulate the autodephosphorylation activity of DegU (R208Q, D249G, M195I, L248F, and D250N) and stabilized DegU in the phosphorylated form. These mutant DegS proteins mimic the effect of DegQ on wild-type DegSU in vitro. Interestingly, DegQ stabilizes phosphorylated DegS only in the presence of DegU, indicating a complex interaction of these three proteins. PMID:21965392

  8. The Codice digitale degli archivi veronesi. A research instrument

    Directory of Open Access Journals (Sweden)

    Andrea Brugnoli

    2014-04-01

    Full Text Available The Codice digitale degli archivi veronesi (Verona’s archives digital code ‹http://cdavr.dtesis.univr.it› makes available online the digital reproductions of the documents produced by corporate bodies and family of Verona between the eighth and twelfth century. The framework of the site reflects the current organisation of the archives. A brief description of the circumstances around the creation of each archive, the corporate body or individual responsible for it and its structure is provided. Each archival unit is identified by its key elements: chronological date, name and qualification of the notary, original/copy, main editions.

  9. The Codice digitale degli archivi veronesi. A research instrument

    Directory of Open Access Journals (Sweden)

    Andrea Brugnoli

    2014-04-01

    Full Text Available The Codice digitale degli archivi veronesi (Verona’s archives digital code ‹http://cdavr.dtesis.univr.it› makes available online the digital reproductions of the documents produced by corporate bodies and family of Verona between the eighth and twelfth century. The framework of the site reflects the current organisation of the archives. A brief description of the circumstances around the creation of each archive, the corporate body or individual responsible for it and its structure is provided. Each archival unit is identified by its key elements: chronological date, name and qualification of the notary, original/copy, main editions.

  10. Islam, rappresentanza degli interessi religiosi e diritto comune europeo *

    Directory of Open Access Journals (Sweden)

    Gianfranco Macrì

    2011-03-01

    Full Text Available Contributo destinato alla pubblicazione negli Atti del Convegno: Europa e Islam. Ridiscutere i fondamenti per la disciplina delle libertà religiose, svoltosi a Salerno il 3 dicembre 2007.SOMMARIO: Premessa - 1. La società «reticolare» europea: sistema di governance e valori unificanti - 2. Europa e fenomeno religioso - 3. La sostanza del Trattato di Lisbona e il ruolo delle organizzazioni religiose - 4. Il dibattito interno all’Islam europeo - 5. La Carta dei musulmani d’Europa - 6. La rappresentanza degli interessi religiosi dell’Islam in Europa - Conclusioni.

  11. The Modelling and Characteristic Analysis of Brushless Synchronous Motor with Sinusoidal back EMF

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Il Nam [Dong Seoul College (Korea); Baek, Soo Hyun; Maeng, In Jae; Yoon, Shin Yong; Baek, Soo Hyun [Dongguk University (Korea); Kim, Cherl Jin [Hanlla University (Korea)

    2000-06-01

    This paper presents the mathematical analysis of Brushless Synchronous Motor(BLSM). The dynamic and the steady state characteristics of BLSM are simulated and analyzed : electromagnetic torque, speed, line voltage, and current. We used mathematical modelling to model of BLSM with sinusoidal back EMF, namely the shaft transformation referencing rotor frame from a, b, c three phase frame to d-q two phase frame. Therefore, the BLSM induced a sinusoidal back EMF requires sinusoidal current to produce constant torque like synchronous motor. The experiment result has already similar to compare with simulation result : torque error about 7%, speed error about 5%. The validity of proposed modelling and analysis was confirmed by the experimental result. (author). 11 refs., 14 figs., 1 tab.

  12. The Integrity bare-metal stent made by continuous sinusoid technology.

    Science.gov (United States)

    Turco, Mark A

    2011-05-01

    The Integrity Coronary Stent System (Medtronic Vascular, CA, USA) is a low-profile, open-cell, cobalt-chromium-alloy advanced bare-metal iteration of the well-known Driver/Micro-Driver Coronary Stent System (Medtronic Vascular). The Integrity stent is made with a process called continuous sinusoid technology. This process allows stent construction via wrapping a single thin strand of wire around a mandrel in a sinusoid configuration, with laser fusion of adjacent crowns. The wire-forming process and fusion pattern provide the stent with a continuous preferential bending plane, intended to allow easier access to, and smoother tracking within, distal and tortuous vessels while radial strength is maintained. Continuous sinusoid technology represents innovation in the design of stent platforms and will provide a future stent platform for newer technology, including drug-eluting stent platforms, drug-filled stents and core wire stents.

  13. Is the sinusoidal obstructive syndrome post-liver transplantation a pathologic entity with a multifactorial etiology?

    Directory of Open Access Journals (Sweden)

    Luis Miguel Marín-Gómez

    2015-04-01

    Full Text Available The sinusoidal obstructive syndrome is a complication typically associated with hematopoietic stem cell transplantation. This syndrome, more commonly known as veno-occlusive disease, has also been described after liver transplantation. It can have a life-threatening course. Herein, we describe the hepatic graft loss secondary to the development of a sinusoidal obstructive syndrome after a severe acute cellular rejection and toxic levels of once daily modified released tacrolimus (TAC. We discuss the role of the endotheliitis of acute rejection and toxic metabolites of some immunosuppressants such as azathioprine and TAC. Based on the current scientific evidence, we contemplate the possibility that the etiology of sinusoidal obstruction syndrome post-liver transplantation is multifactorial.

  14. Ascites due to pre-sinusoidal portal hypertension in dogs: a retrospective analysis of 17 cases.

    Science.gov (United States)

    James, F E; Knowles, G W; Mansfield, C S; Robertson, I D

    2008-05-01

    Accumulation of a pure transudate abdominal effusion in the absence of significant hypoalbuminaemia is uncommon in dogs and is due to pre-sinusoidal portal hypertension. Reported causes of pre-sinusoidal portal hypertension vary, but suggest a reasonable prognosis. A retrospective analysis of 17 dogs that presented to our institution with ascites due to pre-sinusoidal portal hypertension identified idiopathic hepatic fibrosis or canine chronic hepatitis as the underlying cause in the majority of cases. Twelve (70.5%) dogs were 4 years of age or younger at time of presentation. Total serum protein was higher in dogs with chronic hepatitis than it was in dogs without inflammatory disease. The prognosis was generally poor and no histological, imaging or biochemical parameters were useful as prognostic indicators. Dogs died or were euthanased due to severe clinical signs associated with the portal hypertension and/or perceived poor prognosis.

  15. An alternating periodic-chaotic ISI sequence of HH neuron under external sinusoidal stimulus

    Institute of Scientific and Technical Information of China (English)

    Jin Wu-Yin; Xu Jian-Xue; Wu Ying; Hong Ling

    2004-01-01

    A study of Hodgkin-Huxley (HH) neuron under external sinusoidal excited stimulus is presented in this paper. As is well known, the stimulus frequency is to be considered as a bifurcate parameter, and numerous phenomena, such as synchronization, period, and chaos appear alternatively with the changing of the stimulus frequency. For the stimulus frequency less than 2fB (fB being the base frequency in this paper), the simulation results demonstrate that the single HH neuron could completely convey the sinusoidal signal in anti-phase into interspike interval (ISI) sequences. We also report, perhaps for the first time, another kind of phenomenon, the beat phenomenon, which exists in the phase dynamics of the ISI sequences of the HH neuron stimulated by a sinusoidal current. It is shown furthermore that intermittent transition results in the general route to chaos.

  16. New Canonic Active RC Sinusoidal Oscillator Circuits Using Second-Generation Current Conveyors with Application as a Wide-Frequency Digitally Controlled Sinusoid Generator

    Directory of Open Access Journals (Sweden)

    Abhirup Lahiri

    2011-01-01

    Full Text Available This paper reports two new circuit topologies using second-generation current conveyors (CCIIs for realizing variable frequency sinusoidal oscillators with minimum passive components. The proposed topologies in this paper provide new realizations of resistance-controlled and capacitor-controlled variable frequency oscillators (VFOs using only four passive components. The first topology employs three CCIIs, while the second topology employs two CCIIs. The second topology provides an advantageous feature of frequency tuning through two grounded elements. Application of the proposed circuits as a wide-frequency range digitally controlled sinusoid generator is exhibited wherein the digital frequency control has been enabled by replacing both the capacitors by two identical variable binary capacitor banks tunable by means of the same binary code. SPICE simulations of the CMOS implementation of the oscillators using 0.35 μm TSMC CMOS technology parameters and bipolar implementation of the oscillators using process parameters for NR200N-2X (NPN and PR200N-2X (PNP of bipolar arrays ALA400-CBIC-R have validated their workability. One of the oscillators (with CMOS implementation is exemplified as a digitally controlled sinusoid generator with frequency generation from 25 kHz to 6.36 MHz, achieved by switching capacitors and with power consumption of 7 mW in the entire operating frequency range.

  17. Sinusoidal excitation on the Chua's circuit simulation of limit cycles and chaos

    DEFF Research Database (Denmark)

    Lindberg, Erik

    1994-01-01

    Experiments with modelling and simulation of sinusoidal excitation on Chua's circuit are presented. It is demonstrated that the behaviour of the circuit is based on the interaction of two different kinds of energy balance: chaotic behaviour based on a balance between two unstable “states of charg......Experiments with modelling and simulation of sinusoidal excitation on Chua's circuit are presented. It is demonstrated that the behaviour of the circuit is based on the interaction of two different kinds of energy balance: chaotic behaviour based on a balance between two unstable “states...

  18. Modified Smith predictor for frequency identification and disturbance rejection of single sinusoidal signal.

    Science.gov (United States)

    Zheng, Da; Fang, Jian'an; Ren, Zhengyun

    2010-01-01

    This paper presents a frequency identification and disturbance rejection scheme for open loop stable time delay systems with disturbance containing a constant signal and a single sinusoidal signal. Astrom's modified Smith predictor is employed to maintain good setpoint tracking performance. Disturbance rejection controller is designed via internal model control principle and functions as a finite dimensional repetitive controller. Extended Kalman filter is designed to track the frequency of unknown periodic disturbance. The simulation results demonstrate the successful performance of the proposed disturbance rejection method for controlling a linear system with time delays, subjected to both step and sinusoidal disturbances.

  19. Microscopic structured light 3D profilometry: Binary defocusing technique vs. sinusoidal fringe projection

    Science.gov (United States)

    Li, Beiwen; Zhang, Song

    2017-09-01

    This paper compares the binary defocusing technique with conventional sinusoidal fringe projection under two different 3D microscopic profilometry systems: (1) both camera and projector use telecentric lenses and (2) only camera uses a telecentric lens. Our simulation and experiments found that the binary defocusing technique is superior to the traditional sinusoidal fringe projection method by improving the measurement resolution approximately 19%. Finally, by taking the speed advantage of the binary defocusing technique, we presented a high-speed (500 Hz) and high-resolution (1600×1200) 3D microscopic profilometry system that could reach kHz.

  20. Sinusoidal phase-modulating laser diode interferometer for real-time surface profile measurement

    Institute of Scientific and Technical Information of China (English)

    Guotian He; Xiangzhao Wang; Aijun Zeng; Feng Tang

    2007-01-01

    A sinusoidal phase-modulating (SPM) laser diode (LD) interferometer for real-time surface profile measurement is proposed and its principle is analyzed. The phase signal of the surface profile is detected from the sinusoidal phase-modulating interference signal using a real-time phase detection circuit. For 60 × 60 measurement points of the surface profile, the measuring time is 10 ms. A root mean square (RMS) measurement repeatability of 3.93 nm is realized, and the measurement resolution reaches 0.19 nm.

  1. Sinusoidal Vertical Motion of a Sonobuoy Suspension: Experimental Data and a Theoretical Model

    Science.gov (United States)

    2008-06-01

    dB par décade. Selon des expériences, le coefficient d’inertie Ci et le coefficient de frottement Cf d’un disque circulaire en mouvement sinusoïdal... coefficient CI and the drag coefficient CD of a circular disk in sinusoidal motion are in fact not constants, but depend on the dimensionless ratio of...investigation of hydrodynamic added mass and damping of disks in sinusoidal motion revealed that these coefficients may not be constant, but may in fact be

  2. Zoogeografia storica e attuale dei carnivori e degli ungulati italiani

    Directory of Open Access Journals (Sweden)

    Marco Masseti

    2003-10-01

    Full Text Available Come per la maggior parte degli altri paesi europei, anche l'attuale composizione delle specie a mammiferi italiane si prefigura in gran parte come il risultato della plurima e prolungata azione antropica condotta sull'ambiente naturale. Questa, avviatasi alcuni millenni or sono, condiziona oggi più che mai la ridefinizione degli equilibri ecologici del nostro Paese. All'interno dell'attuale teriofauna terrestre italiana viene segnalata la presenza di 18 specie di carnivori e di 9 artiodattili, che può rivelarsi in alcuni casi come il risultato di acclimatazioni e/o naturalizzazioni di specie esotiche avvenute in cronologie diverse, anche di epoca molto recente. All'interno dei confini biogeografici dell'Italia andrebbero anche annoverate quelle popolazioni del cervo pomellato medio-orientale, Axis axis (Erxleben, 1777, che sono state naturalizzate in epoca storica assai recente in Istria ed in alcune isole del golfo del Quarnaro (Brioni Maggiore, Cherso e Plauno. Considerazioni analoghe potrebbero forse essere condotte anche per la diffusione artificiale di Herpestes auropunctatus Hodgson, 1836, su alcune isole della Croazia. Le specie fitofaghe riferibili ai gruppi tassonomici dei lagomorfi e degli artiodattili, e che vengono convenzionalmente comprese nella categoria della cosiddetta "selvaggina", sono tra quelle che hanno più subito un'alterazione condotta in profondità dei quadri faunistici originari, proprio in virtù dell'interesse economico e culturale che ancora rappresentano. Nel caso particolare di queste specie di interesse venatorio ci troviamo quasi sempre di fronte a popolazioni che sono state sottoposte ad intensa gestione e che hanno subito frequenti estinzioni locali seguite da reiterate reintroduzioni. Attualmente, data l'espansione sia naturale che artificiale degli ecotipi indigeni e di quelli alloctoni, si osserva ormai una sovrapposizione degli areali, per cui sembra piuttosto difficile riuscire in

  3. Environmental oil spill sensitivity atlas for the West Greenland (68 deg.-72 deg. N) coastal zone, 2nd revised edition

    Energy Technology Data Exchange (ETDEWEB)

    Clausen, D.; Johansen, Kasper L.; Mosbech, A.; Boertmann, D.; Wegeberg, S.

    2012-12-15

    This oil spill sensitivity atlas covers the shoreline and the offshore areas of West Greenland between 68 deg. N and 72 deg. N. The coastal zone is divided into 199 shoreline segments and the offshore zone into 8 areas. A sensitivity index value is calculated for each segment/area, and each segment/area is subsequently ranked according to four degrees of sensitivity. Besides this general ranking a number of smaller areas are especially selected as they are of particular significance, they are especially vulnerable to oil spills and they have a size making oil spill response possible. The shoreline sensitivity ranking are shown on 37 maps (in scale 1:250,000), which also show the different elements included and the selected areas. Coast types, logistics and proposed response methods along the coasts are shown on another 37 maps. The sensitivities of the offshore zones are depicted on 4 maps, one for each season. Based on all the information, appropriate oil spill response methods have been assessed for each area. (Author)

  4. On the rms anisotropy at 7 deg and 10 deg observed in the COBE-DMR two year sky maps

    Science.gov (United States)

    Banday, A. J.; Gorski, K. M.; Tenorio, L.; Wright, E. L.; Smoot, G. F.; Lineweaver, C. H.; Kogut, A.; Hinshaw, G.; Bennett, C. L.

    1994-01-01

    The frequency-independent rms temperature fluctuations determined from the Cosmic Background Explorer-Differential Microwave Radiometer (COBE-DMR) two-year sky maps are used to infer the parameter Q(sub rms-PS), which characterizes the normalization of power-law models of primordial cosmological temperature anisotropy, for a forced fit to a scale-invariant Harrison-Zel'dovich (n = 1) spectral model. Using a joint analysis of the 7 deg and 10 deg 'cross'-rms derived from both the 53 and 90 GHz sky maps, we find Q(sub rms-PS) = 17.0(sub -2.1 sup +2.5) micro Kelvin when the low quadrupole is included, and Q(sub rms-PS) = 19.4(sub -2.1 sup +2.3) micro Kelvin excluding the quadrupole. These results are consistent with the n = 1 fits from more sensitive methods. The effect of the low quadrupole derived from the COBE-DMR data on the inferred Q(sub rms-PS) normalization is investigated. A bias to lower Q(sub rms-PS) is found when the quadrupole is included. The higher normalization for a forced n = 1 fit is then favored by the cross-rms technique.

  5. The generalization of A. E. Kennelly theory of complex representation of the electrical quantities in sinusoidal periodic regime to the one and three-phase electric quantities in non-sinusoidal periodic regime

    CERN Document Server

    Mihai, Gheorghe

    2010-01-01

    In this paper, a new mathematical method of electrical circuits calculus is proposed based on the theory of the complex linear operators in matrix form. The newly proposed method generalizes the theory of complex representation of electrical quantities in sinusoidal periodic regime to the non-sinusoidal periodic regime.

  6. Mimicking liver sinusoidal structures and functions using a 3D-configured microfluidic chip.

    Science.gov (United States)

    Du, Yu; Li, Ning; Yang, Hao; Luo, Chunhua; Gong, Yixin; Tong, Chunfang; Gao, Yuxin; Lü, Shouqin; Long, Mian

    2017-02-28

    Physiologically, four major types of hepatic cells - the liver sinusoidal endothelial cells, Kupffer cells, hepatic stellate cells, and hepatocytes - reside inside liver sinusoids and interact with flowing peripheral cells under blood flow. It is hard to mimic an in vivo liver sinusoid due to its complex multiple cell-cell interactions, spatiotemporal construction, and mechanical microenvironment. Here we developed an in vitro liver sinusoid chip by integrating the four types of primary murine hepatic cells into two adjacent fluid channels separated by a porous permeable membrane, replicating liver's key structures and configurations. Each type of cells was identified with its respective markers, and the assembled chip presented the liver-specific unique morphology of fenestration. The flow field in the liver chip was quantitatively analyzed by computational fluid dynamics simulations and particle tracking visualization tests. Intriguingly, co-culture and shear flow enhance albumin secretion independently or cooperatively, while shear flow alone enhances HGF production and CYP450 metabolism. Under lipopolysaccharide (LPS) stimulations, the hepatic cell co-culture facilitated neutrophil recruitment in the liver chip. Thus, this 3D-configured in vitro liver chip integrates the two key factors of shear flow and the four types of primary hepatic cells to replicate key structures, hepatic functions, and primary immune responses and provides a new in vitro model to investigate the short-duration hepatic cellular interactions under a microenvironment mimicking the physiology of a liver.

  7. Iron Losses in Electrical Machines Due to Non Sinusoidal Alternating Fluxes

    DEFF Research Database (Denmark)

    Ritchie, Ewen; Walker, J.A.; Dorrell, D. G.

    2007-01-01

    This paper shows how the flux waveform in the core of an electrical machine can be vary non- sinusoidally which complicates the calculation of the iron loss in a machine. A set of tests are conducted on a steel sample using an Epstein square where harmonics are injected into the flux waveform which...

  8. A Perceptual Model for Sinusoidal Audio Coding Based on Spectral Integration

    Directory of Open Access Journals (Sweden)

    Jensen Søren Holdt

    2005-01-01

    Full Text Available Psychoacoustical models have been used extensively within audio coding applications over the past decades. Recently, parametric coding techniques have been applied to general audio and this has created the need for a psychoacoustical model that is specifically suited for sinusoidal modelling of audio signals. In this paper, we present a new perceptual model that predicts masked thresholds for sinusoidal distortions. The model relies on signal detection theory and incorporates more recent insights about spectral and temporal integration in auditory masking. As a consequence, the model is able to predict the distortion detectability. In fact, the distortion detectability defines a (perceptually relevant norm on the underlying signal space which is beneficial for optimisation algorithms such as rate-distortion optimisation or linear predictive coding. We evaluate the merits of the model by combining it with a sinusoidal extraction method and compare the results with those obtained with the ISO MPEG-1 Layer I-II recommended model. Listening tests show a clear preference for the new model. More specifically, the model presented here leads to a reduction of more than 20% in terms of number of sinusoids needed to represent signals at a given quality level.

  9. Measurement of definite integral of sinusoidal signal absolute value third power using digital stochastic method

    Directory of Open Access Journals (Sweden)

    Beljić Željko

    2017-01-01

    Full Text Available In this paper a special case of digital stochastic measurement of the third power of definite integral of sinusoidal signal’s absolute value, using 2-bit AD converters is presented. This case of digital stochastic method had emerged from the need to measure power and energy of the wind. Power and energy are proportional to the third power of wind speed. Anemometer output signal is sinusoidal. Therefore an integral of the third power of sinusoidal signal is zero. Two approaches are proposed for the third power calculation of the wind speed signal. One approach is to use absolute value of sinusoidal signal (before AD conversion for which there is no need of multiplier hardware change. The second approach requires small multiplier hardware change, but input signal remains unchanged. For the second approach proposed minimal hardware change was made to calculate absolute value of the result after AD conversion. Simulations have confirmed theoretical analysis. Expected precision of wind energy measurement of proposed device is better than 0,00051% of full scale. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. TR32019

  10. Theta-frequency resonance in hippocampal CA1 neurons in vitro demonstrated by sinusoidal current injection.

    Science.gov (United States)

    Leung, L S; Yu, H W

    1998-03-01

    Sinusoidal currents of various frequencies were injected into hippocampal CA1 neurons in vitro, and the membrane potential responses were analyzed by cross power spectral analysis. Sinusoidal currents induced a maximal (resonant) response at a theta frequency (3-10 Hz) in slightly depolarized neurons. As predicted by linear systems theory, the resonant frequency was about the same as the natural (spontaneous) oscillation frequency. However, in some cases, the resonant frequency was higher than the spontaneous oscillation frequency, or resonance was found in the absence of spontaneous oscillations. The sharpness of the resonance (Q), measured by the peak frequency divided by the half-peak power bandwidth, increased from a mean of 0.44 at rest to 0.83 during a mean depolarization of 6.5 mV. The phase of the driven oscillations changed most rapidly near the resonant frequency, and it shifted about 90 degrees over the half-peak bandwidth of 8.4 Hz. Similar results were found using a sinusoidal function of slowly changing frequency as the input. Sinusoidal currents of peak-to-peak intensity of >100 pA may evoke nonlinear responses characterized by second and higher harmonics. The theta-frequency resonance in hippocampal neurons in vitro suggests that the same voltage-dependent phenomenon may be important in enhancing a theta-frequency response when hippocampal neurons are driven by medial septal or other inputs in vivo.

  11. New Results on Single-Channel Speech Separation Using Sinusoidal Modeling

    DEFF Research Database (Denmark)

    Mowlaee, Pejman; Christensen, Mads Græsbøll; Jensen, Søren Holdt

    2011-01-01

    We present new results on single-channel speech separation and suggest a new separation approach to improve the speech quality of separated signals from an observed mix- ture. The key idea is to derive a mixture estimator based on sinusoidal parameters. The proposed estimator is aimed at finding...

  12. Dislocation Majorana zero modes in perovskite oxide 2DEG

    Science.gov (United States)

    Chung, Suk Bum; Chan, Cheung; Yao, Hong

    2016-05-01

    Much of the current experimental efforts for detecting Majorana zero modes have been centered on probing the boundary of quantum wires with strong spin-orbit coupling. The same type of Majorana zero mode can also be realized at crystalline dislocations in 2D superconductors with the nontrivial weak topological indices. Unlike at an Abrikosov vortex, at such a dislocation, there is no other low-lying midgap state than the Majorana zero mode so that it avoids usual complications encountered in experimental detections such as scanning tunneling microscope (STM) measurements. We will show that, using the anisotropic dispersion of the t2g orbitals of Ti or Ta atoms, such a weak topological superconductivity can be realized when the surface two-dimensional electronic gas (2DEG) of SrTiO3 or KTaO3 becomes superconducting, which can occur through either intrinsic pairing or proximity to existing s-wave superconductors.

  13. Giant magnetic quadrupole resonance studied with 180 deg. electron scattering

    CERN Document Server

    Neumann-Cosel, P V

    1999-01-01

    The nuclei sup 4 sup 8 Ca and sup 9 sup 0 Zr were investigated in 180 deg. high-resolution inelastic electron scattering for momentum transfers q approx =0.35-0.8 fm sup - sup 1. Complete M2 strength distributions could be extracted in both nuclei up to excitation energies of about 15 MeV utilizing a fluctuation analysis technique. Second-RPA calculations successfully describe the experimentally observed strong fragmentation of the M2 mode. The quenching of the spin part is found to be comparable to the M1 case, contrary to previous claims suggesting a stronger reduction. A quantitative reproduction of the data requires the presence of appreciable orbital strength which can be interpreted as a torsional elastic vibration (the so-called twist mode).

  14. Laicità: finitezza degli ordini e governo delle differenze

    Directory of Open Access Journals (Sweden)

    Nicola Colaianni

    2013-12-01

    Full Text Available Testo della relazione al Convegno Nazionale dell’ADEC sul tema “Per una disciplina che cambia. Il diritto canonico e il diritto ecclesiastico nel tempo presente” (Bologna, 7-9 novembre 2013, destinata alla pubblicazione negli Atti del Convegno. Contributo non sottoposto a valutazioneSOMMARIO: 1. La laicità dei giudici – 2. La laicità dei giuristi – 3. Né regola né valore: un principio – 4. La finitezza degli ordini distinti: dalle materie miste alla sfera dell’indecidibile – 5. L’aconfessionalità sostanziale: a ex parte ecclesiae – 6. (segue: b ex parte status – 7. La laicità come governance delle differenze.

  15. LA FORMAZIONE DEGLI ETNICI NELLA RIFLESSIONE LINGUISTICA DI FRANCESCO CHERUBINI

    Directory of Open Access Journals (Sweden)

    Federica Guerini

    2016-09-01

    Full Text Available Il presente contributo si propone di fornire una descrizione della struttura del Vocabolario Patronimico di Francesco Cherubini e delle fonti empiriche consultate per la sua compilazione. Si accennerà poi a due questioni ricorrenti nel dibattito sulla formazione degli etnici in italiano, ovvero, la presenza di varianti allomorfiche o suppletive, e la motivazione morfo-pragmatica sottesa all’impiego di alcuni suffissi derivativi nella formazione di etnici e aggettivi deonomastici, cercando di chiarire quale attenzione tali tematiche abbiano ricevuto nella riflessione linguistica di Francesco Cherubini. Si formuleranno infine alcune osservazioni conclusive, evidenziando luci ed ombre del Vocabolario Patronimico e sottolineando alcuni degli spunti che tale opera ancora può offrire agli studiosi contemporanei. The formation of ethnic words in Francesco Cherubini’s reflection on language  The aim of this paper is to describe the structure and contents of Francesco Cherubini’s Vocabolario Patronimico, as well as the empirical sources consulted for its compilation. We will address two of the most common issues in the debate on the formation of ethnic nouns and adjectives in Italian, namely the existence of allomorphs and supplementary variants, and the morpho-pragmatic motivation displayed by some of the derivative suffixes occurring in ethnic nouns and adjectives derived from both personal and place names. We will offer a few observations on the place occupied by the above-mentioned issues in Cherubini’s thought and, by analyzing the strengths and weaknesses of the Vocabolario Patronimico, we will draw attention to a few topics which may be of some interest to contemporary scholars.

  16. Portal and sinusoidal fibrosis are common on liver biopsy after Fontan surgery.

    Science.gov (United States)

    Schwartz, Matthew C; Sullivan, Lisa M; Glatz, Andrew C; Rand, Elizabeth; Russo, Pierre; Goldberg, David J; Rome, Jonathan J; Cohen, Meryl S

    2013-01-01

    Hepatic fibrosis is an important complication after Fontan surgery in patients with single-ventricle congenital heart disease. Few reports of hepatic histology in these patients exist, and sinusoidal fibrosis has been described. We aimed to characterize fibrosis at liver biopsy procedure in patients with previous Fontan surgery and to identify patient variables associated with the degree of fibrosis. All patients who had previous Fontan surgery and who subsequently underwent liver biopsy at our institution between January 1990 and July 2010 were identified. For each biopsy specimen, portal and sinusoidal fibrosis were graded and medical records reviewed. Biopsy specimens from 13 patients were examined; the median time from Fontan surgery to liver biopsy procedure was 16.9 years (range 6.9-25). At the most recent biopsy procedure, 12 patients (92 %) had evidence of portal fibrosis, including 1 patient with portal-based cirrhosis. Thirteen patients (100 %) had at least some degree of sinusoidal fibrosis, including 1 patient with centrilobular-based cirrhosis. Lower platelet count was associated with greater degree of portal fibrosis by ordinal regression (odds ratio 0.84, P = 0.04), and patients with no or mild portal fibrosis had significantly higher platelet counts compared with those with moderate or severe portal disease (278 ± 78 K vs. 160 ± 46 K, P = 0.005). Four patients underwent serial biopsy procedures; portal fibrosis was progressed in 3 patients, and sinusoidal fibrosis was progressed in 3 patients. After Fontan surgery, portal and sinusoidal fibrosis are common at liver biopsy and can progress over time. Lower platelet count may represent a marker of portal-based disease in these patients.

  17. A 360-deg Digital Image Correlation system for materials testing

    Science.gov (United States)

    Genovese, K.; Cortese, L.; Rossi, M.; Amodio, D.

    2016-07-01

    The increasing research interest toward natural and advanced engineered materials demands new experimental protocols capable of retrieving highly dense sets of experimental data on the full-surface of samples under multiple loading conditions. Such information, in fact, would allow to capture the possible heterogeneity and anisotropy of the material by using up-to-date inverse characterization methods. Although the development of object-specific test protocols could represent the optimal choice to address this need, it is unquestionable that universal testing machines (UTM) remain the most widespread and versatile option to test materials and components in both academic and industrial contexts. A major limitation of performing standard material tests with UTM, however, consists in the scarce information obtainable with the commonly associated sensors since they provide only global (LVDTs, extensometers, 2D-video analyzers) or local (strain gages) measures of displacement and strain. This paper presents a 3D Digital Image Correlation (DIC) system developed to perform highly accurate full-surface 360-deg measurements on either standard or custom-shaped samples under complex loading within universal testing machines. To this aim, a low cost and easy to setup video rig was specifically designed to overcome the practical limitations entailed with the integration of a multi-camera system within an already existing loading frame. In particular, the proposed system features a single SLR digital camera moved through multiple positions around the specimen by means of a large rotation stage. A proper calibration and data-processing procedure allows to automatically merge the experimental data obtained from the multiple views with an accuracy of 10-2 m m . The results of a full benchmarking of the metrological performances of the system are here reported and discussed together with illustrative examples of full-360-deg shape and deformation measurements on a Grade X65 steel

  18. COSMOS Photometric Redshifts with 30-bands for 2-deg2

    CERN Document Server

    Ilbert, O; Salvato, M; Aussel, H; McCracken, H J; Sanders, D B; Scoville, N; Kartaltepe, J; Arnouts, S; Le Floc'h, E; Mobasher, B; Taniguchi, Y; Lamareille, F; Leauthaud, A; Sasaki, S; Thompson, D; Zamojski, M; Zamorani, G; Bardelli, S; Bolzonella, M; Bongiorno, A; Brusa, M; Caputi, K I; Carollo, C M; Contini, T; Cook, R; Coppa, G; Cucciati, O; De la Torre, S; de Ravel, L; Franzetti, P; Garilli, B; Hasinger, G; Iovino, A; Kampczyk, P; Kneib, J -P; Knobel, C; Kovac, K; Le Borgne, J F; Le Brun, V; Le Fèvre, O; Lilly, S; Looper, D; Maier, C; Mainieri, V; Mellier, Y; Mignoli, M; Murayama, T; Pellò, R; Peng, Y; Pérez-Montero, E; Renzini, A; Ricciardelli, E; Schiminovich, D; Scodeggio, M; Shioya, Y; Silverman, Joseph; Surace, J; Tanaka, M; Tasca, L; Tresse, L; Vergani, D; Zucca, E

    2008-01-01

    We present accurate photometric redshifts in the 2-deg2 COSMOS field. The redshifts are computed with 30 broad, intermediate, and narrow bands covering the UV (GALEX), Visible-NIR (Subaru, CFHT, UKIRT and NOAO) and mid-IR (Spitzer/IRAC). A chi2 template-fitting method (Le Phare) was used and calibrated with large spectroscopic samples from VLT-VIMOS and Keck-DEIMOS. We develop and implement a new method which accounts for the contributions from emission lines (OII, Hbeta, Halpha and Ly) to the spectral energy distributions (SEDs). The treatment of emission lines improves the photo-z accuracy by a factor of 2.5. Comparison of the derived photo-z with 4148 spectroscopic redshifts (i.e. Delta z = zs - zp) indicates a dispersion of sigma_{Delta z/(1+zs)}=0.007 at i<22.5, a factor of 2-6 times more accurate than earlier photo-z in the COSMOS, CFHTLS and COMBO-17 survey fields. At fainter magnitudes i<24 and z<1.25, the accuracy is sigma_{Delta z/(1+zs)}=0.012. The deep NIR and IRAC coverage enables the ph...

  19. LE ZANZARE ITALIANE: GENERALITÀ E IDENTIFICAZIONE DEGLI ADULTI (DIPTERA, CULICIDAE

    Directory of Open Access Journals (Sweden)

    Francesco Severini

    2009-12-01

    Full Text Available Nel presente lavoro vengono riportate le informazioni essenziali su tassonomia e biologia nonché sugli aspetti ecologici degli adulti dei Culicidi italiani. Attualmente la fauna culicidica italiana comprende 64 specie appartenenti a 2 sottofamiglie e 8 generi. Alla sottofamiglia Anophelinae appartiene soltanto il genere Anopheles, presente con 16 specie raggruppate in due sottogeneri. Alla sottofamiglia Culicinae appartengono i rimanenti 7 generi: Aedes con 6 specie raggruppate in 3 sottogeneri, Coquillettidia con 2 specie, Ochlerotatus con 20 specie raggruppate in 3 sottogeneri, Culex con 12 specie raggruppate in 4 sottogeneri, Culiseta con 6 specie raggruppate in 3 sottogeneri, Orthopodomyia e Uranotaenia con una specie ognuna. In questo contesto vengono fornite le chiavi di identificazione specifica per le zanzare adulte, in italiano e in inglese. Le chiavi sono corredate da un’ampia iconografia (figure 1-75. Alle chiavi fa seguito la diagnosi morfologica dell’adulto di ogni specie con note sulla relativa biologia e distribuzione. Per ulteriori approfondimenti viene riportata la bibliografia completa sulle zanzare della fauna italiana dal 1960 ed i precedenti lavori più autorevoli.

  20. Come e cosa desidera la narrativa italiana degli anni Zero

    Directory of Open Access Journals (Sweden)

    Gianluigi Simonetti

    2013-05-01

    Full Text Available L'articolo analizza il trattamento del tema del desiderio - erotico e amoroso - nel romanzo italiano degli ultimi anni, impegnandosi nell'esame ravvicinato di alcuni testi esemplari. La campionatura vuole da un lato isolare alcune opere rappresentative della situazione attuale della narrativa contemporanea, dall'altro  proporre un'ipotesi categoriale che seziona il campo di studio in tre parti; il sondaggio sembra infatti suggerire che le dinamiche del desiderio vengono rese in maniera specifica nei diversi ambiti della letteratura di consumo, in quella di 'nobile intrattenimento' e in quella 'forte' e letterariamente più ambiziosa. L'analisi formale risulta insomma integrata a una prospettiva di stroria dello stile, secondo un metodo che permette di utilizzare la figuralità letteraria come 'indicatore sociologico' di processi politici (e forse antropologici in atto.

  1. Le caratteristiche degli acquirenti e venditori di abitazioni

    Directory of Open Access Journals (Sweden)

    Erika Ghiraldo

    2011-12-01

    Full Text Available L’incrocio dei dati contenuti nelle dichiarazioni dei redditi con quelli contenuti negli archivi della Pubblicità Immobiliare (ex Conservatorie rende disponibili molte informazioni sulle caratteristiche dei contraenti che hanno effettuato una compravendita di unità immobiliari. Considerando principalmente le compravendite di unità immobiliari del settore residenziale effettuate da persone fisiche sono trattate informazioni sul reddito dichiarato al fisco, l’età e l’attività di lavoro prevalente. È fornito un quadro sintetico della distribuzione delle compravendite, in termini di Numero di Transazioni Normalizzate (NTN e per dimensione delle abitazioni, per ciascuna caratteristica sia per gli acquirenti che per i venditori. La disponibilità dell’informazione sulla residenza dei soggetti consente, inoltre, di condurre un’analisi sulla provenienza degli acquirenti rispetto al luogo di ubicazione dell’immobile compravenduto. E’ possibile così analizzare la composizione del mercato distinguendo la quota di acquisti imputabile a soggetti residenti nello stesso Comune di ubicazione dell’immobile (mercato comunale dalla quota alimentata da soggetti residenti in altro Comune di una stessa provincia (mercato infraprovinciale o di altra provincia (mercato extra-provinciale. Quest’ultima indagine risulta molto interessante se effettuata su singole città. Sono, quindi, riportati i risultati dell’analisi per i mercati delle città di Milano, Roma e Napoli.

  2. Advanced Energy Conversion System Using Sinusoidal Voltage Tracking Buck-Boost Converter Cascaded Polarity Changing Inverter

    Science.gov (United States)

    Ahmed, Nabil A.

    2011-06-01

    This paper presents an advanced power converter employs a sinusoidal voltage absolute value tracking buck-boost DC-DC converter in the first power processing stage and a polarity changing full-bridge inverter in the second stage. The proposed power conversion system has the capability of delivering sinusoidal output and input current with unity power factor and good output voltage regulation. Consequently, the complete voltage regulator system, which is mainly suitable for new energy generation systems as well as energy storage systems, can be constructed compactly and inexpensively without DC link electrolytic capacitor. Also, the paper presents an auxiliary passive resonant circuit for soft switching operation. Simulation results using PSIM software are presented to verify the operation principles and feasibility of the proposed power conversion system.

  3. Credibility Test for Frequency Estimation of Sinusoid Using Chebyshev’s Inequality

    Directory of Open Access Journals (Sweden)

    Hu Guobing

    2014-01-01

    Full Text Available Estimation of sinusoid frequency is a key research problem related to radar, sonar, and communication systems. The results of numerous investigations on frequency estimation have been reported in the literature. Nevertheless, to the best of our knowledge, none of them have dealt with credibility evaluation, which is used to decide whether an individual frequency estimate of the sinusoid is accurate or not. In this study, the credibility problem is modeled as a hypothesis test based on Chebyshev’s inequality (CI. The correlation calculated from the received signal and the reference signal generated according to the frequency estimate is used as a test statistic. A threshold is determined based on CI, and the analytical expression for the frequency estimation credibility detection performance is derived. Simulations show that the proposed method performs well even at low signal-to-noise ratios.

  4. Direct Vector Control of Induction Motor Based on Sinusoidal PWM Inverter with Fuzzy Logic Controller

    Directory of Open Access Journals (Sweden)

    Nirban Chakraborty

    2014-04-01

    Full Text Available This paper presents the speed control scheme of direct vector control of Induction Motor drive (IM drive. The Fuzzy logic controller is (FLC used as the controller part here for the direct vector control of Induction Motor using Sinusoidal PWM Inverter (SPWM. Fuzzy logic controller has become a very popular controlling scheme in the field of Industrial application. The entire module of this IM is divided into several parts such as IM body module, Inverter module, coordinate transformation module and Sinusoidal pulse width modulation (SPWM production module and so on. With the help of this module we can analyze a variety of different simulation waveforms, which provide an effective means for the analysis and design of the IM control system using FLC technique.

  5. Color-Phase Analysis for Sinusoidal Structured Light in Rapid Range Imaging

    CERN Document Server

    Je, Changsoo; Park, Rae-Hong

    2015-01-01

    Active range sensing using structured-light is the most accurate and reliable method for obtaining 3D information. However, most of the work has been limited to range sensing of static objects, and range sensing of dynamic (moving or deforming) objects has been investigated recently only by a few researchers. Sinusoidal structured-light is one of the well-known optical methods for 3D measurement. In this paper, we present a novel method for rapid high-resolution range imaging using color sinusoidal pattern. We consider the real-world problem of nonlinearity and color-band crosstalk in the color light projector and color camera, and present methods for accurate recovery of color-phase. For high-resolution ranging, we use high-frequency patterns and describe new unwrapping algorithms for reliable range recovery. The experimental results demonstrate the effectiveness of our methods.

  6. Parameters estimation of sinusoidal frequency modulation signal with application in synthetic aperture radar imaging

    Science.gov (United States)

    Wang, Yong; Wang, Zhaofa; Zhao, Bin; Xu, Liang

    2016-04-01

    A method for estimating the parameters of the sinusoidal frequency modulation (SFM) signal is presented in this paper. Based on the modified discrete sinusoid frequency modulation transform (DSFMT), the SFM signal can be transformed into the DSFMT domain where it is energy-concentrated and then the parameters can be estimated by the global maximum. To search for the location of the global maximum with less computational load, particle swarm optimization is used in this paper. Then the algorithm is used in the synthetic aperture radar imaging with high frequency vibration of the platform, and the focus performance can be improved significantly. Simulation results demonstrate the effectiveness of the method proposed in this paper.

  7. Non-sinusoidal waveform effects on heat transfer performance in pulsating pipe flow

    Directory of Open Access Journals (Sweden)

    R. Roslan

    2016-12-01

    Full Text Available In the present paper, an unsteady motion of fluid flow in a pulsating pipe is studied to determine the effect of non-sinusoidal waveforms on the heat transfer performance. Three non-sinusoidal waveforms, namely sawtooth, square and triangular waveforms have been considered. Explicit analytical expressions for a periodic laminar flow describing the flow and heat transfer at small and large times with sawtooth and square pressure waveforms have been derived using Bessel transform technique. The heat transfer performance of periodic flow at sawtooth and square pressure waveforms has been compared with the published result for triangular waveform [1]. The temperature performance for a triangular waveform pressure is very different from the sawtooth and square pressure waveforms.

  8. Discrimination of steady state and transient state of dither extremum seeking control via sinusoidal detection

    Science.gov (United States)

    Mu, Baojie; Li, Yaoyu; Seem, John E.

    2016-08-01

    A major class of extremum seeking control (ESC) is based on the use of periodic dither perturbation of plant input for extracting the gradient information. Presence of the dither input into the steady state operation is undesirable in practice due to the possible excessive wear of actuators. It is thus beneficial to stop the dithering action after the ESC reaches its steady state. In this paper, we propose a method for automatically discriminating between the steady state and the transient state modes of extremum seeking control process using the sinusoidal detection techniques. Some design guidelines are proposed for the parameter selection of the relevant sinusoidal detection scheme. The proposed scheme is validated with simulation study on dynamic virtual plant of two building HVAC systems.

  9. DESIGN OF TWO-PHASE SINUSOIDAL POWER CLOCK AND CLOCKED TRANSMISSION GATE ADIABATIC LOGIC CIRCUIT

    Institute of Scientific and Technical Information of China (English)

    Wang Pengjun; Yu Junjun

    2007-01-01

    First the research is conducted on the design of the two-phase sinusoidal power clock generator in this paper. Then the design of the new adiabatic logic circuit adopting the two-phase sinusoidal power clocks-Clocked Transmission Gate Adiabatic Logic (CTGAL) circuit is presented. This circuit makes use of the clocked transmission gates to sample the input signals, then the output loads are charged and discharged in a fully adiabatic manner by using bootstrapped N-Channel Metal Oxide Semiconductor (NMOS) and Complementary Metal Oxide Semiconductor (CMOS) latch structure.Finally, with the parameters of Taiwan Semiconductor Manufacturing Company (TSMC) 0.25 μm CMOS device, the transient energy consumption of CTGAL, Bootstrap Charge-Recovery Logic (BCRL)and Pass-transistor Adiabatic Logic (PAL) including their clock generators is simulated. The simulation result indicates that CTGAL circuit has the characteristic of remarkably low energy consumption.

  10. Synthesis of Voltages of Multiple Uniform PWM, Generated by Trapezoidal and Sinusoidal Functions

    Directory of Open Access Journals (Sweden)

    A. Ctryzhniou

    2013-01-01

    Full Text Available The problem of synthesis and qualitative estimation of the harmonic composition of voltages of multiple uniform PWM pulses generated by trapezoidal and sinusoidal functions is considered. Analytical expressions for PWM pulses parameters ai  and ti have been received and they can be used for program-based generation of multiple uniform PWM, determination of n-harmonic magnitude in pulse-width regulation and AC motor operation simulation.

  11. Mechanisms of xenogeneic baboon platelet aggregation and phagocytosis by porcine liver sinusoidal endothelial cells.

    Directory of Open Access Journals (Sweden)

    Qiang Peng

    Full Text Available BACKGROUND: Baboons receiving xenogeneic livers from wild type and transgenic pigs survive less than 10 days. One of the major issues is the early development of profound thrombocytopenia that results in fatal hemorrhage. Histological examination of xenotransplanted livers has shown baboon platelet activation, phagocytosis and sequestration within the sinusoids. In order to study the mechanisms of platelet consumption in liver xenotransplantation, we have developed an in vitro system to examine the interaction between pig endothelial cells with baboon platelets and to thereby identify molecular mechanisms and therapies. METHODS: Fresh pig hepatocytes, liver sinusoidal and aortic endothelial cells were isolated by collagenase digestion of livers and processing of aortae from GTKO and Gal+ MGH-miniature swine. These primary cell cultures were then tested for the differential ability to induce baboon or pig platelet aggregation. Phagocytosis was evaluated by direct observation of CFSE labeled-platelets, which are incubated with endothelial cells under confocal light microscopy. Aurintricarboxylic acid (GpIb antagonist blocking interactions with von Willebrand factor/vWF, eptifibatide (Gp IIb/IIIa antagonist, and anti-Mac-1 Ab (anti-α(Mβ(2 integrin Ab were tested for the ability to inhibit phagocytosis. RESULTS: None of the pig cells induced aggregation or phagocytosis of porcine platelets. However, pig hepatocytes, liver sinusoidal and aortic endothelial cells (GTKO and Gal+ all induced moderate aggregation of baboon platelets. Importantly, pig liver sinusoidal endothelial cells efficiently phagocytosed baboon platelets, while pig aortic endothelial cells and hepatocytes had minimal effects on platelet numbers. Anti-MAC-1 Ab, aurintricarboxylic acid or eptifibatide, significantly decreased baboon platelet phagocytosis by pig liver endothelial cells (P<0.01. CONCLUSIONS: Although pig hepatocytes and aortic endothelial cells directly caused

  12. Suppression of axonal conduction by sinusoidal stimulation in rat hippocampus in vitro

    Science.gov (United States)

    Jensen, A. L.; Durand, D. M.

    2007-06-01

    Deep brain stimulation (DBS), also known as high frequency stimulation (HFS), is a well-established therapy for Parkinson's disease and essential tremor, and shows promise for the therapeutic control of epilepsy. However, the direct effect of DBS on neural elements close to the stimulating electrode remains an important unanswered question. Computational studies have suggested that HFS has a dual effect on neural elements inhibiting cell bodies, while exciting axons. Prior experiments have shown that sinusoidal HFS (50 Hz) can suppress synaptic and non-synaptic cellular activity in several in vitro epilepsy models, in all layers of the hippocampus. However, the effects of HFS on axons near the electrode are still unclear. In the present study, we tested the hypothesis that HFS suppresses axonal conduction in vitro. Sinusoidal HFS was applied to the alvear axon field of transverse rat hippocampal slices. The results show that HFS suppresses the alvear compound action potential (CAP) as well as the CA1 antidromic evoked potential (AEP). Complete suppression was observed as a 100% reduction in the amplitude of the evoked field potential for the duration of the stimulus. Evoked potential width and latency were not significantly affected by sinusoidal HFS. Suppression was dependent on HFS amplitude and frequency, but independent of stimulus duration and synaptic transmission. The frequency dependence of sinusoidal HFS is similar to that observed in clinical DBS, with maximal suppression between 50 and 200 Hz. HFS produced not only suppression of axonal conduction but also a correlated rise in extracellular potassium. These data provide new insights into the effects of HFS on neuronal elements, and show that HFS can block axonal activity through non-synaptic mechanisms.

  13. Frequency Estimation of Single-Tone Sinusoids Under Additive and Phase Noise

    OpenAIRE

    Asmaa Nazar Almoosawy; Zahir M. Hussain; Fadel A. Murad

    2014-01-01

    We investigate the performance of main frequency estimation methods for a single-component complex sinusoid under complex additive white Gaussian noise (AWGN) as well as phase noise (PN). Two methods are under test: Maximum Likelihood (ML) method using Fast Fourier Transform (FFT), and the autocorrelation method (Corr). Simulation results showed that FFT-method has superior performance as compared to the Corr-method in the presence of additive white Gaussian noise (affecting the amplitude) an...

  14. Application of a Notch Digital Filter to Elimination of Sinusoidal Disturbances from Helicopter Flight Data.

    Science.gov (United States)

    1986-04-01

    disturbances. An optimal Kalman filtering approach was found to be impractical [2]. However, additional research showed that the .. optimal filter...Evans, R.J. - "Application of Fast Fourier Transforms to Sinusoidal Disturbance Rejection and its -. , Relationship to Kalman Filtering". University of...1206 .......... F% .9 REQUEHCY Hz Fiue9 Feunc epneo Csae oc Filtr fo ALPA=0975 nd d-0.1 I. %.0. .2

  15. Effects of continuous-wave, pulsed, and sinusoidal-amplitude-modulated microwaves on brain energy metabolism.

    Science.gov (United States)

    Sanders, A P; Joines, W T; Allis, J W

    1985-01-01

    A comparison of the effects of continuous-wave, sinusoidal-amplitude-modulated, and pulsed square-wave-modulated 591-MHz microwave exposures on brain energy metabolism was made in male Sprague-Dawley rats (175-225 g). Brain NADH fluorescence, adenosine triphosphate (ATP) concentration, and creatine phosphate (CP) concentration were determined as a function of modulation frequency. Brain temperatures of animals were maintained between -0.1 and -0.4 degrees C from the preexposure temperature when subjected to as much as 20 mW/cm2 (average power) CW, pulsed, or sinusoidal-amplitude modulated 591-MHz radiation for 5 min. Sinusoidal-amplitude-modulated exposures at 16-24 Hz showed a trend toward preferential modulation frequency response in inducing an increase in brain NADH fluorescence. The pulse-modulated and sinusoidal-amplitude-modulated (16 Hz) microwaves were not significantly different from CW exposures in inducing increased brain NADH fluorescence and decreased ATP and CP concentrations. When the pulse-modulation frequency was decreased from 500 to 250 pulses per second the average incident power density threshold for inducing an increase in brain NADH fluorescence increased by a factor of 4--ie, from about 0.45 to about 1.85 mW/cm2. Since brain temperature did not increase, the microwave-induced increase in brain NADH and decrease in ATP and CP concentrations was not due to hyperthermia. This suggests a direct interaction mechanism and is consistent with the hypothesis of microwave inhibition of mitochondrial electron transport chain function of ATP production.

  16. Gene expression profiling provides insights into pathways of oxaliplatin-related sinusoidal obstruction syndrome in humans

    OpenAIRE

    Rubbia-Brandt, Laura; Tauzin, Sébastien; Brezault, Catherine; Delucinge-Vivier, Céline; Descombes, Patrick; Dousset, Bertand; Majno, Pietro; Mentha, Gilles; Terris, Benoit

    2011-01-01

    Sinusoidal obstruction syndrome (SOS; formerly veno-occlusive disease) is a well-established complication of hematopoietic stem cell transplantation, pyrrolizidine alkaloid intoxication, and widely used chemotherapeutic agents such as oxaliplatin. It is associated with substantial morbidity and mortality. Pathogenesis of SOS in humans is poorly understood. To explore its molecular mechanisms, we used Affymetrix U133 Plus 2.0 microarrays to investigate the gene expression profile of 11 human l...

  17. Intravascular Immune Surveillance by CXCR6+ NKT Cells Patrolling Liver Sinusoids

    Directory of Open Access Journals (Sweden)

    Geissmann Frederic

    2005-01-01

    Full Text Available We examined the in vivo behavior of liver natural killer T cells (NKT cells by intravital fluorescence microscopic imaging of mice in which a green fluorescent protein cDNA was used to replace the gene encoding the chemokine receptor CXCR6. NKT cells, which account for most CXCR6+ cells in liver, were found to crawl within hepatic sinusoids at 10-20 µm/min and to stop upon T cell antigen receptor activation. CXCR6-deficient mice exhibited a selective and severe reduction of CD1d-reactive NKT cells in the liver and decreased susceptibility to T-cell-dependent hepatitis. CXCL16, the cell surface ligand for CXCR6, is expressed on sinusoidal endothelial cells, and CXCR6 deficiency resulted in reduced survival, but not in altered speed or pattern of patrolling of NKT cells. Thus, NKT cells patrol liver sinusoids to provide intravascular immune surveillance, and CXCR6 contributes to liver-based immune responses by regulating their abundance.

  18. Intravascular immune surveillance by CXCR6+ NKT cells patrolling liver sinusoids.

    Directory of Open Access Journals (Sweden)

    Frederic Geissmann

    2005-04-01

    Full Text Available We examined the in vivo behavior of liver natural killer T cells (NKT cells by intravital fluorescence microscopic imaging of mice in which a green fluorescent protein cDNA was used to replace the gene encoding the chemokine receptor CXCR6. NKT cells, which account for most CXCR6(+ cells in liver, were found to crawl within hepatic sinusoids at 10-20 microm/min and to stop upon T cell antigen receptor activation. CXCR6-deficient mice exhibited a selective and severe reduction of CD1d-reactive NKT cells in the liver and decreased susceptibility to T-cell-dependent hepatitis. CXCL16, the cell surface ligand for CXCR6, is expressed on sinusoidal endothelial cells, and CXCR6 deficiency resulted in reduced survival, but not in altered speed or pattern of patrolling of NKT cells. Thus, NKT cells patrol liver sinusoids to provide intravascular immune surveillance, and CXCR6 contributes to liver-based immune responses by regulating their abundance.

  19. Sensor-less pseudo-sinusoidal drive for a permanent-magnet brushless ac motor

    Science.gov (United States)

    Liu, Li-Hsiang; Chern, Tzuen-Lih; Pan, Ping-Lung; Huang, Tsung-Mou; Tsay, Der-Min; Kuang, Jao-Hwa

    2012-04-01

    The precise rotor-position information is required for a permanent-magnet brushless ac motor (BLACM) drive. In the conventional sinusoidal drive method, either an encoder or a resolver is usually employed. For position sensor-less vector control schemes, the rotor flux estimation and torque components are obtained by complicated coordinate transformations. These computational intensive methods are susceptible to current distortions and parameter variations. To simplify the method complexity, this work presents a sensor-less pseudo-sinusoidal drive scheme with speed control for a three-phase BLACM. Based on the sinusoidal drive scheme, a floating period of each phase current is inserted for back electromotive force detection. The zero-crossing point is determined directly by the proposed scheme, and the rotor magnetic position and rotor speed can be estimated simultaneously. Several experiments for various active angle periods are undertaken. Furthermore, a current feedback control is included to minimize and compensate the torque fluctuation. The experimental results show that the proposed method has a competitive performance compared with the conventional drive manners for BLACM. The proposed scheme is straightforward, bringing the benefits of sensor-less drive and negating the need for coordinate transformations in the operating process.

  20. Sequentially Adapted Parallel Feedforward Active Noise Control of Noisy Sinusoidal Signals

    Directory of Open Access Journals (Sweden)

    Govind Kannan

    2009-01-01

    Full Text Available A large class of acoustic noise sources has an underlying periodic process that generates a periodic noise component, and thus their acoustic noise can in general be modeled as the sum of a periodic signal and a randomly fluctuating signal (usually a broadband background noise. Active control of periodic noise (i.e., for a mixture of sinusoids is more effective than that of random noise. For mixtures of sinusoids in a background broadband random noise, conventional FXLMS-based single filter method does not reach the maximum achievable Noise Attenuation Level (NALmax⁡. In this paper, an alternative approach is taken and the idea of a parallel active noise control (ANC architecture for cancelling mixtures of periodic and random signals is presented. The proposed ANC system separates the noise into periodic and random components and generates corresponding antinoises via separate noise cancelling filters, and tends to reach NALmax⁡ consistently. The derivation of NALmax⁡ is presented. Both the separation and noise cancellation are based on adaptive filtering. Experimental results verify the analytical development by showing superior performance of the proposed method, over the single-filter approach, for several cases of sinusoids in white noise.

  1. Discrimination of real and virtual surfaces with sinusoidal and triangular gratings using the fingertip and stylus.

    Science.gov (United States)

    Kocsis, M B; Cholewiak, S A; Traylor, R M; Adelstein, B D; Hirleman, E Daniel; Tan, H Z

    2013-01-01

    Two-interval two-alternative forced-choice discrimination experiments were conducted separately for sinusoidal and triangular textured surface gratings from which amplitude (i.e., height) discrimination thresholds were estimated. Participants (group sizes: n = 4 to 7) explored one of these texture types either by fingertip on real gratings (Finger real), by stylus on real gratings (Stylus real), or by stylus on virtual gratings (Stylus virtual). The real gratings were fabricated from stainless steel by an electrical discharge machining process while the virtual gratings were rendered via a programmable force-feedback device. All gratings had a 2.5-mm spatial period. On each trial, participants compared test gratings with 55, 60, 65, or 70 μm amplitudes against a 50-μm reference. The results indicate that discrimination thresholds did not differ significantly between sinusoidal and triangular gratings. With sinusoidal and triangular data combined, the average (mean + standard error) for the Stylus-real threshold (2.5 ± 0.2 μm) was significantly smaller (p <; 0.01) than that for the Stylus-virtual condition (4.9 ± 0.2 μm). Differences between the Finger-real threshold (3.8 ± 0.2 μm) and those from the other two conditions were not statistically significant. Further studies are needed to better understand the differences in perceptual cues resulting from interactions with real and virtual gratings.

  2. Evaluation of Steel Shear Walls Behavior with Sinusoidal and Trapezoidal Corrugated Plates

    Directory of Open Access Journals (Sweden)

    Emad Hosseinpour

    2015-01-01

    Full Text Available Reinforcement of structures aims to control the input energy of unnatural and natural forces. In the past four decades, steel shear walls are utilized in huge constructions in some seismic countries such as Japan, United States, and Canada to lessen the risk of destructive forces. The steel shear walls are divided into two types: unstiffened and stiffened. In the former, a series of plates (sinusoidal and trapezoidal corrugated with light thickness are used that have the postbuckling field property under overall buckling. In the latter, steel profile belt series are employed as stiffeners with different arrangement: horizontal, vertical, or diagonal in one side or both sides of wall. In the unstiffened walls, increasing the thickness causes an increase in the wall capacity under large forces in tall structures. In the stiffened walls, joining the stiffeners to the wall is costly and time consuming. The ANSYS software was used to analyze the different models of unstiffened one-story steel walls with sinusoidal and trapezoidal corrugated plates under lateral load. The obtained results demonstrated that, in the walls with the same dimensions, the trapezoidal corrugated plates showed higher ductility and ultimate bearing compared to the sinusoidal corrugated plates.

  3. Sinusoidal nanotextures for light management in silicon thin-film solar cells

    Science.gov (United States)

    Köppel, G.; Rech, B.; Becker, C.

    2016-04-01

    Recent progresses in liquid phase crystallization enabled the fabrication of thin wafer quality crystalline silicon layers on low-cost glass substrates enabling conversion efficiencies up to 12.1%. Because of its indirect band gap, a thin silicon absorber layer demands for efficient measures for light management. However, the combination of high quality crystalline silicon and light trapping structures is still a critical issue. Here, we implement hexagonal 750 nm pitched sinusoidal and pillar shaped nanostructures at the sun-facing glass-silicon interface into 10 μm thin liquid phase crystallized silicon thin-film solar cell devices on glass. Both structures are experimentally studied regarding their optical and optoelectronic properties. Reflection losses are reduced over the entire wavelength range outperforming state of the art anti-reflective planar layer systems. In case of the smooth sinusoidal nanostructures these optical achievements are accompanied by an excellent electronic material quality of the silicon absorber layer enabling open circuit voltages above 600 mV and solar cell device performances comparable to the planar reference device. For wavelengths smaller than 400 nm and higher than 700 nm optical achievements are translated into an enhanced quantum efficiency of the solar cell devices. Therefore, sinusoidal nanotextures are a well-balanced compromise between optical enhancement and maintained high electronic silicon material quality which opens a promising route for future optimizations in solar cell designs for silicon thin-film solar cells on glass.

  4. Motion Stability Analysis of Non-sinusoidal Oscillation of Mold Driven by Servomotor

    Institute of Scientific and Technical Information of China (English)

    YAO Yunfeng; LI Junxia; FANG Yiming

    2015-01-01

    The investments of the electro-hydraulic servo system of the mold non-sinusoidal oscillator are great, the modification ratio of the mechanical type is unable to be adjusted online, and some continuous casters suffer from server resonance during the casting. A mold non-sinusoidal oscillation mechanism driven by servomotor is proposed and the prototype is produced in the lab, the investment is low and the modification ratio is can be adjusted online, and the stability problem is studied. At first the dynamics model of the servomotor non-sinusoidal oscillation is established, and the kinematics differential function is deduced. Furthermore, based on the harmonic balance method, the eigenvalues of the system are solved; the criterion of the stability of the system is put forward. In addition, the eigenvalues and harmonic with different oscillating parameters are analyzed. Analytical results show that the real parts of the eigenvalues are positive, the system will be unstable, and the resonance will occur when the positive real parts of the eigenvalues are extremum. A foundation is established for solving the running smooth problem and next application of this mechanism.

  5. Photoluminescence of a High Mobility 2DEG in the Fractional Quantum Hall Effect Regime

    Science.gov (United States)

    Smirnov, D.; Rudenkov, V. V.; Ashkinadze, B. M.; Cohen, E.; Christianen, P. C. M.; Maan, J. C.; Pfeiffer, L. N.

    The magneto-PL spectra of modulation-doped, ultra-high mobility GaAs/AlGaAs single heterojunctions (HJs) were studied under a perpendicularly applied magnetic field up to 33 T and at temperatures of 0.3 and 1.2 K. The spectra show remarkable intensity redistribution between free (bulk) exciton and 2DEG-hole PL channels occurring at electron filling factors, ν = 2 and 1. At 0.3 K, significant 2DEG-hole PL spectral changes are observed near ν = 2/3 and 1/3. Several heterojunctions with 2DEG density in the range of n2D - (1 - 2.7) · 1011 cm-2 display similar features. These spectral peculiarities are attributed to the modification of the 2DEG energy spectrum caused by the e-e interaction, in particular, the recombination of valence hole with the composite (fractionally-charged) particles of the magnetized 2DEG. In HJs with lower n2D < 1011 cm-2, the observed PL evolution at ν < 1 is mainly determined by an intensity redistribution between the σ+ and σ- circularly-polarized free exciton PL components. In this case, the exciton energy is lower than the energy of the 2DEG-hole system, so that the free excitons do not dissociate near the magnetized 2DEG and thus, the 2DEG-hole PL is barely observed.

  6. Structural and functional aspects of the liver and liver sinusoidal cells in relation to colon carcinoma metastasis

    Institute of Scientific and Technical Information of China (English)

    Katrien Vekemans; Filip Braet

    2005-01-01

    Nowadays, liver metastasis remains difficult to cure. When tumor cells escape and arrive in the liver sinusoids, they encounter the local defense mechanism specific to the liver. The sinusoidal cells have been widely described in physiologic conditions and in relation to metastasis during the past 30 years. This paper provides an "overview" of how these cells function in health and in diseases such as liver metastasis.

  7. Accelerated transformation of brushite to octacalcium phosphate in new biomineralization media between 36.5 deg. C and 80 deg. C

    Energy Technology Data Exchange (ETDEWEB)

    Temizel, Neslihan; Girisken, Giray; Tas, A. Cuneyt, E-mail: cuneyt-tas@ouhsc.edu

    2011-07-20

    This study investigated the hydrothermal transformation of brushite (dicalcium phosphate dihydrate, DCPD, CaHPO{sub 4}.2H{sub 2}O) into octacalcium phosphate (OCP, Ca{sub 8}(HPO{sub 4}){sub 2}(PO{sub 4}){sub 4}.5H{sub 2}O) in seven different newly developed biomineralization media, all inspired from the commercial DMEM solutions, over the temperature range of 36.5 deg. C to 90 deg. C with aging times varying between 1 h and 6 days. DCPD powders used in this study were synthesized in our laboratory by using a wet-chemical technique. DCPD was found to transform into OCP in the Ca{sup 2+}, Mg{sup 2+}, Na{sup +}, K{sup +}, HCO{sub 3}{sup -}, Cl{sup -} and H{sub 2}PO{sub 4}{sup -} containing aqueous biomineralization media in less than 72 h at 36.5 deg. C, without stirring. The same medium was able to convert DCPD into OCP in about 2 h at 75-80 deg. C, again without a need for stirring. Samples were characterized by using powder X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). - Research highlights: {yields} New biomineralization solutions developed to convert DCPD into OCP at 36.5 deg. C to 80 deg. C. {yields} DCPD powder was the starting material. {yields} OCP was synthesized under static conditions (no need for stirring). {yields} OCP was synthesized in sealed glass media bottles in solutions free of Hepes or Tris. {yields} OCP can be synthesized at 75-80 deg. C in only 2 hours in the above solutions without stirring.

  8. AtDeg2 – a chloroplast protein with dual protease/chaperone activity

    Directory of Open Access Journals (Sweden)

    Przemysław Jagodzik

    2014-07-01

    Full Text Available Chloroplast protease AtDeg2 (an ATP-independent serine endopeptidase is cytosolically synthesized as a precursor, which is imported into the chloroplast stroma and deprived of its transit peptide. Then the mature protein undergoes routing to its functional location at the stromal side of thylakoid membrane. In its linear structure AtDeg2 molecule contains the protease domain with catalytic triad (HDS and two PDZ domains (PDZ1 and PDZ2. In vivo AtDeg2 most probably exists as a supposedly inactive haxamer, which may change its oligomeric stage to form active 12-mer, or 24-mer. AtDeg2 has recently been demonstrated to exhibit dual protease/chaperone function. This review is focused on the current awareness with regard to AtDeg2 structure and functional significance.

  9. Patologie sociali, resistenze e difese degli insegnanti nell’istituzione scolastica: Considerazioni cliniche e pedagogiche

    Directory of Open Access Journals (Sweden)

    Tommaso Fratini

    2014-12-01

    Full Text Available L’articolo prende in esame il tema di alcune resistenze e difese degli insegnanti all’interno dell’istituzione scolastica. Partendo dall’attuale condizione di emergenza della scuola italiana e rifacendosi al concetto di patologia sociale di Giuseppe Di Chiara, viene argomentato come tali resistenze coprano le angosce persecutorie degli insegnanti nel loro lavoro scolastico quotidiano nel rapporto con gli allievi. L’articolo, tra le varie forme di patologia istituzionale, affronta principalmente il tema di quelle che presiedono alle resistenze degli insegnanti al lavoro introspettivo con il proprio mondo interno, conseguenza e ulteriore cagione di sensi di colpa nel rapporto con gli allievi e di fenomeni di burnout lavorativo degli stessi insegnanti. Tali fenomeni vanno nella direzione del rinforzo sia di un atteggiamento di chiusura verso la collaborazione con professionisti esterni all’istituzione scolastica, sia di un atteggiamento di minore empatia e vicinanza emotiva con la realtà interna degli allievi.

  10. Temperature dependent dynamics of DegP-trimer: A molecular dynamics study.

    Science.gov (United States)

    Rai, Nivedita; Ramaswamy, Amutha

    2015-01-01

    DegP is a heat shock protein from high temperature requirement protease A family, which reacts to the environmental stress conditions in an ATP independent way. The objective of the present analysis emerged from the temperature dependent functional diversity of DegP between chaperonic and protease activities at temperatures below and above 28 °C, respectively. DegP is a multimeric protein and the minimal functional unit, DegP-trimer, is of great importance in understanding the DegP pathway. The structural aspects of DegP-trimer with respect to temperature variation have been studied using molecular dynamics simulations (for 100 ns) and principal component analysis to highlight the temperature dependent dynamics facilitating its functional diversity. The DegP-trimer revealed a pronounced dynamics at both 280 and 320 K, when compared to the dynamics observed at 300 K. The LA loop is identified as the highly flexible region during dynamics and at extreme temperatures, the residues 46-80 of LA loop express a flip towards right (at 280) and left ( at 320 K) with respect to the fixed β-sheet connecting the LA loop of protease for which Phe46 acts as one of the key residues. Such dynamics of LA loop facilitates inter-monomeric interaction with the PDZ1 domain of the neighbouring monomer and explains its active participation when DegP exists as trimer. Hence, the LA loop mediated dynamics of DegP-trimer is expected to provide further insight into the temperature dependent dynamics of DegP towards the understanding of its assembly and functional diversity in the presence of substrate.

  11. Temperature dependent dynamics of DegP-trimer: A molecular dynamics study

    Directory of Open Access Journals (Sweden)

    Nivedita Rai

    2015-01-01

    Full Text Available DegP is a heat shock protein from high temperature requirement protease A family, which reacts to the environmental stress conditions in an ATP independent way. The objective of the present analysis emerged from the temperature dependent functional diversity of DegP between chaperonic and protease activities at temperatures below and above 28 °C, respectively. DegP is a multimeric protein and the minimal functional unit, DegP-trimer, is of great importance in understanding the DegP pathway. The structural aspects of DegP-trimer with respect to temperature variation have been studied using molecular dynamics simulations (for 100 ns and principal component analysis to highlight the temperature dependent dynamics facilitating its functional diversity. The DegP-trimer revealed a pronounced dynamics at both 280 and 320 K, when compared to the dynamics observed at 300 K. The LA loop is identified as the highly flexible region during dynamics and at extreme temperatures, the residues 46–80 of LA loop express a flip towards right (at 280 and left ( at 320 K with respect to the fixed β-sheet connecting the LA loop of protease for which Phe46 acts as one of the key residues. Such dynamics of LA loop facilitates inter-monomeric interaction with the PDZ1 domain of the neighbouring monomer and explains its active participation when DegP exists as trimer. Hence, the LA loop mediated dynamics of DegP-trimer is expected to provide further insight into the temperature dependent dynamics of DegP towards the understanding of its assembly and functional diversity in the presence of substrate.

  12. 3D hepatic cultures simultaneously maintain primary hepatocyte and liver sinusoidal endothelial cell phenotypes.

    Directory of Open Access Journals (Sweden)

    Yeonhee Kim

    Full Text Available Developing in vitro engineered hepatic tissues that exhibit stable phenotype is a major challenge in the field of hepatic tissue engineering. However, the rapid dedifferentiation of hepatic parenchymal (hepatocytes and non-parenchymal (liver sinusoidal endothelial, LSEC cell types when removed from their natural environment in vivo remains a major obstacle. The primary goal of this study was to demonstrate that hepatic cells cultured in layered architectures could preserve or potentially enhance liver-specific behavior of both cell types. Primary rat hepatocytes and rat LSECs (rLSECs were cultured in a layered three-dimensional (3D configuration. The cell layers were separated by a chitosan-hyaluronic acid polyelectrolyte multilayer (PEM, which served to mimic the Space of Disse. Hepatocytes and rLSECs exhibited several key phenotypic characteristics over a twelve day culture period. Immunostaining for the sinusoidal endothelial 1 antibody (SE-1 demonstrated that rLSECs cultured in the 3D hepatic model maintained this unique feature over twelve days. In contrast, rLSECs cultured in monolayers lost their phenotype within three days. The unique stratified structure of the 3D culture resulted in enhanced heterotypic cell-cell interactions, which led to improvements in hepatocyte functions. Albumin production increased three to six fold in the rLSEC-PEM-Hepatocyte cultures. Only rLSEC-PEM-Hepatocyte cultures exhibited increasing CYP1A1/2 and CYP3A activity. Well-defined bile canaliculi were observed only in the rLSEC-PEM-Hepatocyte cultures. Together, these data suggest that rLSEC-PEM-Hepatocyte cultures are highly suitable models to monitor the transformation of toxins in the liver and their transport out of this organ. In summary, these results indicate that the layered rLSEC-PEM-hepatocyte model, which recapitulates key features of hepatic sinusoids, is a potentially powerful medium for obtaining comprehensive knowledge on liver metabolism

  13. Unique cell type-specific junctional complexes in vascular endothelium of human and rat liver sinusoids.

    Directory of Open Access Journals (Sweden)

    Cyrill Géraud

    Full Text Available Liver sinusoidal endothelium is strategically positioned to control access of fluids, macromolecules and cells to the liver parenchyma and to serve clearance functions upstream of the hepatocytes. While clearance of macromolecular debris from the peripheral blood is performed by liver sinusoidal endothelial cells (LSECs using a delicate endocytic receptor system featuring stabilin-1 and -2, the mannose receptor and CD32b, vascular permeability and cell trafficking are controlled by transcellular pores, i.e. the fenestrae, and by intercellular junctional complexes. In contrast to blood vascular and lymphatic endothelial cells in other organs, the junctional complexes of LSECs have not yet been consistently characterized in molecular terms. In a comprehensive analysis, we here show that LSECs express the typical proteins found in endothelial adherens junctions (AJ, i.e. VE-cadherin as well as α-, β-, p120-catenin and plakoglobin. Tight junction (TJ transmembrane proteins typical of endothelial cells, i.e. claudin-5 and occludin, were not expressed by rat LSECs while heterogenous immunreactivity for claudin-5 was detected in human LSECs. In contrast, junctional molecules preferentially associating with TJ such as JAM-A, B and C and zonula occludens proteins ZO-1 and ZO-2 were readily detected in LSECs. Remarkably, among the JAMs JAM-C was considerably over-expressed in LSECs as compared to lung microvascular endothelial cells. In conclusion, we show here that LSECs form a special kind of mixed-type intercellular junctions characterized by co-occurrence of endothelial AJ proteins, and of ZO-1 and -2, and JAMs. The distinct molecular architecture of the intercellular junctional complexes of LSECs corroborates previous ultrastructural findings and provides the molecular basis for further analyses of the endothelial barrier function of liver sinusoids under pathologic conditions ranging from hepatic inflammation to formation of liver metastasis.

  14. Reliability of utricular function testing sinusoidal translation profile during unilateral centrifugation.

    Science.gov (United States)

    Buytaert, K I; Vanspauwen, R; Van de Heyning, P H; Wuyts, F L

    2010-01-01

    The unilateral centrifugation test is one of the few vestibular tests that evaluate the utricles side by side. During this test, a subject is rotated about an earth vertical axis at high rotation speeds (e.g. 400 degrees/s) and translated sideways along the interaural axis to align the axis of rotation consecutively with the right and the left utricle. The combined rotation and translation induces ocular counter rolling (OCR), which is measured using three-dimensional video-oculography. Recently, a new model has been proposed to analyse the OCR. The model is based on contributions from both the semicircular canals and the utricles. Concomitant with the new model a new stimulation profile using a sinusoidal translation profile during the unilateral centrifugation has been introduced [1]. The current study presents the test-retest reliability as well as the robustness of the new stimulation method, based on data of 67 healthy subjects. Test-retest reliability was based on repeated measurements of a group of subjects. To test the robustness of the new sinusoidal translation paradigm, we investigated the effect of a different amplitude of the sinusoidal translation (6 cm instead of 4 cm) and of an offset in translation (from -3 to +5 cm, instead of from -4 to +4 cm) on the parameters. Several statistical measures were used to reflect the reliability: intraclass correlation coefficient (ICC), the "coefficient of variation of the method error" and the "minimal difference" (MD). All relevant variables from the physiological model for the OCR induced by unilateral centrifugation show a good to excellent reliability during the test-retest study and the relevant parameters remain unaffected by the changes applied to the translation profile (p > 0.05) as predicted by the model. Additionally, all observed differences are smaller than the MD values calculated in the test-retest part of the study.

  15. Superluminescent diode interferometer using sinusoidal phase modulation for step-profile measurement.

    Science.gov (United States)

    Sasaki, O; Ikeada, Y; Suzuki, T

    1998-08-01

    We propose an interferometer in which the relationship between the degree of coherence (DCH) and the optical path difference (OPD) is utilized for determining an OPD longer than a wavelength. A superluminescent diode is employed as the source of the interferometer, and sinusoidal phase-modulating interferometry is used to detect the DCH and the phase of the interference signal. The combination of the OPD determined from the DCH and the phase of an interference signal enables us to measure an OPD longer than a wavelength with a high accuracy of a few nanometers. Experimental results show clearly the usefulness of the interferometer for a step-profile measurement.

  16. Electromagnetic characterization of current transformer with toroidal core under sinusoidal conditions

    Energy Technology Data Exchange (ETDEWEB)

    Koprivica, Branko, E-mail: branko.koprivica@ftn.kg.ac.rs; Milovanovic, Alenka, E-mail: alenka.milovanovic@ftn.kg.ac.rs

    2016-04-01

    The aim of this paper is to present a new procedure for the electromagnetic analysis of a measuring current transformer under sinusoidal conditions in its electrical and magnetic circuit. The influence of the magnetic hysteresis has been taken into account using the measured inverse magnetization curve and phase lag between the time waveforms of the magnetic field and the magnetic induction. Using the proposed analysis, ratio and phase errors of the current transformer have been calculated. The results of the calculation have been compared with experimental results and a good agreement has been found.

  17. Simply Adjustable Sinusoidal Oscillator Based on Negative Three-Port Current Conveyors

    Directory of Open Access Journals (Sweden)

    R. Sotner

    2010-09-01

    Full Text Available The paper deals with sinusoidal oscillator employing two controlled second-generation negative-current conveyors and two capacitors. The proposed oscillator has a simple circuit configuration. Electronic (voltage adjusting of the oscillation frequency and condition of oscillation are possible. The presented circuit is verified in PSpice utilizing macro models of commercially available negative current conveyors. The circuit is also verified by experimental measurements. Important characteristics and drawbacks of the proposed circuit and influences of real active elements in the designed circuit are discussed in detail.

  18. Golden Ratio Sinusoidal Sequences and the Multimode Pulsation of the δ Sct Star V784 Cassiopeiae

    Institute of Scientific and Technical Information of China (English)

    Juan García Escudero

    2004-01-01

    Non periodic ordered sequences obtained by production rules in formal grammars are applied to the analysis of the multi-periodicity of the δ-Scuti type variable star V784 Cas.An artificial light curve for V784 Cas is generated by a non deterministic derivation in a context-sensitive grammar by concatenation of two sinusoidal fragments following certain word sequences.The two basic building blocks represent temporal segments in a golden ratio and the number of long and short segments in a word are also in a golden ratio.

  19. Exact solution of unsteady flow generated by sinusoidal pressure gradient in a capillary tube

    Directory of Open Access Journals (Sweden)

    M. Abdulhameed

    2015-12-01

    Full Text Available In this paper, the mathematical modeling of unsteady second grade fluid in a capillary tube with sinusoidal pressure gradient is developed with non-homogenous boundary conditions. Exact analytical solutions for the velocity profiles have been obtained in explicit forms. These solutions are written as the sum of the steady and transient solutions for small and large times. For growing times, the starting solution reduces to the well-known periodic solution that coincides with the corresponding solution of a Newtonian fluid. Graphs representing the solutions are discussed.

  20. Laminated Magnetic Materials Losses Analysis under Non-Sinusoidal Flux Waveforms in Power Electronics Systems

    CERN Document Server

    Aguglia, D

    2014-01-01

    Losses analyses of laminated magnetic materials subject to non-sinusoidal magnetic flux are presented. Comparative analyses on typical Fe-Si oriented and non-oriented grains and nanocrystalline materials are carried out considering the influence of harmonic phase shift and associated B-H minor loops. Experimental measurements are performed to illustrate the B-H characteristics behaviours. A special experimental effort is given on nanocrystalline material, where Steinmetz coefficients are experimentally identified to analyse the performances of the improved Generalized Steinmetz Equation (iGSE) when phase displaced minor loops occur. It is proven that the iGSE is efficient in predicting nanocrystalline losses versus variable phase displaced harmonics.

  1. Voltage-Mode Four-Phase Sinusoidal Generator and Its Useful Extensions

    Directory of Open Access Journals (Sweden)

    Sudhanshu Maheshwari

    2013-01-01

    Full Text Available This paper introduces a new voltage-mode second-order sinusoidal generator circuit with four active elements and six passive elements, including grounded capacitors. The frequency and condition of oscillation can be independently controlled. The effect of active element’s nonidealities and parasitic effects is also studied; the proposed topology is good in absorbing several parasitic elements involved with the active elements. The circuit is advantageous for generating high frequency signals which is demonstrated for 25 MHz outputs. Several circuit extensions are also given which makes the new proposal useful for real circuit adoption. The proposed theory is validated through simulation results.

  2. Double sinusoidal phase modulating laser diode interferometer for thickness measurements of transparent plates

    Institute of Scientific and Technical Information of China (English)

    Dailin Li(李代林); Xiangzhao Wang(王向朝); Yingming Liu(刘英明)

    2004-01-01

    A double sinusoidal phase modulating (SPM) laser diode interferometer for thickness measurements of a transparent plate is presented. A carrier signal is given to the interference signal by using a piezoelectric transducer, and the SPM interferometry is applied to measure the thickness of a transparent plate. By combining the double-modulation technique with the Bessel function ratio method, the measurement error originating from light intensity fluctuations caused by the modulation current can be decreased greatly.The thicknesses of a glass parallel plate and a quartz glass are measured in real time, and the corresponding experimental results are also given.

  3. Simulation of residual oil displacement in a sinusoidal channel with the lattice Boltzmann method

    CERN Document Server

    Otomo, Hiroshi; Hazlett, Randy; Li, Yong; Staroselsky, Ilya; Zhang, Raoyang; Chen, Hudong

    2016-01-01

    We simulate oil slug displacement in a sinusoidal channel in order to validate computational models and algorithms for multi-component flow. This case fits in the gap between fully realistic cases characterized by complicated geometry and academic cases with simplistic geometry. Our computational model is based on the lattice Boltzmann method and allows for variation of physical parameters such as wettability and viscosity. The effect of variation of model parameters is analyzed, in particular via comparison with analytical solutions. We discuss the requirements for accurate solution of the oil slug displacement problem.

  4. Liver sinusoidal endothelial and biliary cell repopulation following irradiation and partial hepatectomy

    Institute of Scientific and Technical Information of China (English)

    Petra; Krause; Margret; Rave-Frank; Hendrik; Andreas; Wolff; Heinz; Becker; Hans; Christiansen; Sarah; Koenig

    2010-01-01

    AIM: To investigate whether irradiation (IR) and partial hepatectomy (PH) may prepare the host liver for nonparenchymal cell (NPC) transplantation.METHODS: Livers of dipeptidyl peptidase(DPP)-deficient rats were pre-conditioned with external beam IR (25 Gy) delivered to two-thirds of the right liver lobules followed by a one-third PH of the untreated lob-ule. DPP-positive liver cells (NPC preparations enriched for liver sinusoidal endothelial cells (LSECs) and hepatocytes) were transplanted via the spleen i...

  5. Modeling of Electric Disturbance Signals Using Damped Sinusoids via Atomic Decompositions and Its Applications

    Directory of Open Access Journals (Sweden)

    Tcheou Michel P

    2007-01-01

    Full Text Available The number of waveforms monitored in power systems is increasing rapidly. This creates a demand for computational tools that aid in the analysis of the phenomena and also that allow efficient transmission and storage of the information acquired. In this context, signal processing techniques play a fundamental role. This work is a tutorial reviewing the principles and applications of atomic signal modeling of electric disturbance signals. The disturbance signal is modeled using a linear combination of damped sinusoidal components which are closely related to the phenomena typically observed in power systems. The signal model obtained is then employed for disturbance signal denoising, filtering of "DC components," and compression.

  6. Iron losses evaluation in soft magnetic materials with a sinusoidal voltage supply

    DEFF Research Database (Denmark)

    Nedelcu, Steluţa; Ritchie, Ewen; Leban, Krisztina Monika

    2013-01-01

    This paper presents an evaluation method of for specific iron losses in non-oriented laminated steel suitable for electric motors and transformers in the case of a sinusoidal excitation. The model is based on the separation of loss contribution due to hysteresis, eddy currents and excess losses...... and it is proposing an identification procedure for the model coefficients from multi-frequency single sheet tests. The frequencies used are in the range 10 Hz and 150 Hz and with the values of magnetic flux density in the range 0.1 T and 1.4 T. The model was applied on six magnetic materials of different thicknesses...

  7. Analysis and Implementation of Multiple Bionic Motion Patterns for Caterpillar Robot Driven by Sinusoidal Oscillator

    Directory of Open Access Journals (Sweden)

    Yanhe Zhu

    2014-05-01

    Full Text Available Articulated caterpillar robot has various locomotion patterns—which make it adaptable to different tasks. Generally, the researchers have realized undulatory (transverse wave and simple rolling locomotion. But many motion patterns are still unexplored. In this paper, peristaltic locomotion and various additional rolling patterns are achieved by employing sinusoidal oscillator with fixed phase difference as the joint controller. The usefulness of the proposed method is verified using simulation and experiment. The design parameters for different locomotion patterns have been calculated that they can be replicated in similar robots immediately.

  8. Nonlinear Nanofluid Flow over Heated Vertical Surface with Sinusoidal Wall Temperature Variations

    Directory of Open Access Journals (Sweden)

    S. S. Motsa

    2014-01-01

    Full Text Available The nonlinear density temperature variations in two-dimensional nanofluid flow over heated vertical surface with a sinusoidal wall temperature are investigated. The model includes the effects of Brownian motion and thermophoresis. Using the boundary layer approximation, the two-dimensional momentum, heat, and mass transfer equations are transferred to nonlinear partial differential equations form and solved numerically using a new method called spectral local linearisation method. The effects of the governing parameters on the fluid properties and on the heat and nanomass transfer coefficients are determined and shown graphically.

  9. OTRA based second and third order sinusoidal oscillators and their phase noise performance

    Science.gov (United States)

    Komanapalli, Gurumurthy; Pandey, Neeta; Pandey, Rajeshwari

    2017-07-01

    In this paper operational transresistance amplifier (OTRA) based second and third order sinusoidal oscillators are proposed. The proposed second order oscillator is designed using single OTRA based Sallen Key low pass filter structure and third order oscillator is obtained by cascading three low pass filters and placing in a loop. The non-ideality and phase noise analyses of the circuits are also presented with necessary mathematical formulations. Workability of the proposed oscillators are verified through PSPICE simulations using 0.18µm AGILENT CMOS process parameters. The total harmonic distortion (THD) for proposed second order and third order oscillators are found as 3.27% and 0.631% respectively.

  10. Parameters estimation of a noisy sinusoidal signal with time-varying amplitude

    CERN Document Server

    Liu, Da-Yan; Perruquetti, Wilfrid

    2011-01-01

    In this paper, we give estimators of the frequency, amplitude and phase of a noisy sinusoidal signal with time-varying amplitude by using the algebraic parametric techniques introduced by Fliess and Sira-Ramirez. We apply a similar strategy to estimate these parameters by using modulating functions method. The convergence of the noise error part due to a large class of noises is studied to show the robustness and the stability of these methods. We also show that the estimators obtained by modulating functions method are robust to "large" sampling period and to non zero-mean noises.

  11. Parameter Estimation of Gaussian-Damped Sinusoids from a Geometric Perspective

    CERN Document Server

    Pelaia, Thomas

    2016-01-01

    The five parameter gaussian damped sinusoid equation is a reasonable model for betatron motion with chromatic decoherence of the proton bunch centroid signal in the ring at the Spallation Neutron Source. A geometric method for efficiently fitting this equation to the turn by turn signals to extract the betatron tune and damping constant will be presented. This method separates the parameters into global and local parameters and allows the use of vector arithmetic to eliminate the local parameters from the parameter search space. Furthermore, this method is easily generalized to reduce the parameter search space for a larger class of problems.

  12. Using Paraffin with -10 deg C to 10 deg C Melting Point for Payload Thermal Energy Storage in SpaceX Dragon Trunk

    Science.gov (United States)

    Choi, Michael K.

    2013-01-01

    A concept of using paraffin wax phase change material (PCM) with a melting point between -10 deg C and 10 deg C for payload thermal energy storage in a Space Exploration Technologies (SpaceX) Dragon trunk is presented. It overcomes the problem of limited heater power available to a payload with significant radiators when the Dragon is berthed to the International Space Station (ISS). It stores adequate thermal energy to keep a payload warm without power for 6 hours during the transfer from the Dragon to an ExPRESS logistics carrier (ELC) on the ISS.

  13. Far-infrared and submillimeter survey of the galactic plane from l = 11.5 deg to l = 17.5 deg

    Science.gov (United States)

    Campbell, M. F.; Niles, D. W.; Silverberg, R. F.; Hauser, M. G.; Stier, M. T.; Kelsall, T.; Hoffmann, W. F.; Thronson, H. A., Jr.

    1984-01-01

    Medium resolution (11 min) maps of the galactic plane are presented from l = 11.5 deg to l = 17.5 deg at wavelengths of 93 microns, 154 microns, and 190 microns. The maps are interpreted in terms of the temperature and spatial structure of diffuse far-infrared/submillimeter sources associated with evolved H II regions and a continuous ridge of galactic emission. The emission regions are found to be more extended at the longer wavelengths which implies that there must be a range of dust temperatures in the sources. The properties of the galactic ridge are similar to those of the sources.

  14. Thermodestruction of complex sulfates of iridium and ruthenium in sulfate solutions at 100-180 deg C

    Energy Technology Data Exchange (ETDEWEB)

    Sinitsyn, N.M.; Godzhiev, S.E.; Blagodatin, Yu.V. (Moskovskij Inst. Tonkoj Khimicheskoj Tekhnologii (USSR))

    1983-12-01

    Thermodestruction of iridium- and ruthenium complex sulfates in sulfate solutions is studied at 100-180 deg C depending on the solution acidity, hold time, element initial chemical form in the solution, salt background. The complex ruthenium sulfates are shown to be destroyed during high-temperature solution holding with the solid phase formation, the rate of platinum metal transfer into a precipitate increasing with the temperature, hold time and pH of the source solution. Depending on the initial chemical form the thermodestruction proceeds in various ways and leads to the formation of either hydroxides or solid phase ''proper'' of the platinium metal salt. A reduced tendency to high-temperature hydrolysis of complex ruthenium sulfates at the +3 oxidation level is noted.

  15. Wetting of anisotropic sinusoidal surfaces—experimental and numerical study of directional spreading

    Science.gov (United States)

    Fischer, G.; Bigerelle, M.; Kubiak, K. J.; Mathia, T. G.; Khatir, Z.; Anselme, K.

    2014-10-01

    Directional wettability, i.e. the variation of wetting properties, depending on the surface orientation, can be achieved by anisotropic surface texturing. A new high-precision process can produce homogeneous sinusoidal surfaces (in particular, parallel grooves) at the microscale, with a nanoscale residual roughness five orders of magnitude smaller than the texture features. Static wetting experiments have shown that this pattern, even with a very small aspect ratio, can induce a strong variation of the contact angle, depending on the direction of the observation. A comparison with numerical simulations (using Surface Evolver software) shows good agreement and could be used to predict fluid-solid interaction and droplet behaviour on textured surfaces. Two primary mechanisms of directional spreading of water droplets on textured stainless steel surface have been identified. The first one is the mechanical barrier created by the textured surface peaks; this limits spreading in a perpendicular direction to the surface anisotropy. The second one is the capillary action inside of the sinusoidal grooves, which accelerates spreading along the grooves. Spreading has been shown to depend strongly on the history of wetting and internal drop dynamics.

  16. A Novel Modular Bioreactor to In Vitro Study the Hepatic Sinusoid

    Science.gov (United States)

    Illa, Xavi; Vila, Sergi; Yeste, Jose; Peralta, Carmen; Gracia-Sancho, Jordi; Villa, Rosa

    2014-01-01

    We describe a unique, versatile bioreactor consisting of two plates and a modified commercial porous membrane suitable for in vitro analysis of the liver sinusoid. The modular bioreactor allows i) excellent control of the cell seeding process; ii) cell culture under controlled shear stress stimulus, and; iii) individual analysis of each cell type upon completion of the experiment. The advantages of the bioreactor detailed here are derived from the modification of a commercial porous membrane with an elastomeric wall specifically moulded in order to define the cell culture area, to act as a gasket that will fit into the bioreactor, and to provide improved mechanical robustness. The device presented herein has been designed to simulate the in vivo organization of a liver sinusoid and tested by co-culturing endothelial cells (EC) and hepatic stellate cells (HSC). The results show both an optimal morphology of the endothelial cells as well as an improvement in the phenotype of stellate cells, most probably due to paracrine factors released from endothelial cells. This device is proposed as a versatile, easy-to-use co-culture system that can be applied to biomedical research of vascular systems, including the liver. PMID:25375141

  17. Calibration-free sinusoidal rectification and uniform retinal irradiance in scanning light ophthalmoscopy.

    Science.gov (United States)

    Yang, Qiang; Yin, Lu; Nozato, Koji; Zhang, Jie; Saito, Kenichi; Merigan, William H; Williams, David R; Rossi, Ethan A

    2015-01-01

    Sinusoidal rectification (i.e., desinusoiding) is necessary for scanning imaging systems and is typically achieved by calculating a rectification transform from a calibration image such as a regular grid. This approach is susceptible to error due to electronic or mechanical instability that can alter the phase of the imaging window with respect to the calibration transform. Here, we show a calibration-free rectification method implemented from live video of a scanning light ophthalmoscope (SLO) with or without adaptive optics (AO). This approach, which capitalizes on positional differences in the images obtained in the forward and backward scan directions, dynamically keeps the imaging window in phase with the motion of the sinusoidal resonant scanner, preventing errors from signal drift over time. A benefit of this approach is that it allows the light power across the field-of-view (FOV) to be modulated inversely to achieve uniform irradiance on the retina, a feature desirable for functional imaging methods and light safety in SLOs.

  18. Exposure to 50Hz-sinusoidal electromagnetic field induces DNA damage-independent autophagy.

    Science.gov (United States)

    Shen, Yunyun; Xia, Ruohong; Jiang, Hengjun; Chen, Yanfeng; Hong, Ling; Yu, Yunxian; Xu, Zhengping; Zeng, Qunli

    2016-08-01

    As electromagnetic field (EMF) is commonly encountered within our daily lives, the biological effects of EMF are of great concern. Autophagy is a key process for maintaining cellular homeostasis, and it can also reveal cellular responses to environmental stimuli. In this study, we aim to investigate the biological effects of a 50Hz-sinusoidal electromagnetic field on autophagy and we identified its mechanism of action in Chinese Hamster Lung (CHL) cells. CHL cells were exposed to a 50Hz sinusoidal EMF at 0.4mT for 30min or 24h. In this study, we found that a 0.4mT EMF resulted in: (i) an increase in LC3-II expression and increased autophagosome formation; (ii) no significant difference in the incidence of γH2AX foci between the sham and exposure groups; (iii) reorganized actin filaments and increased pseudopodial extensions without promoting cell migration; and (iv) enhanced cell apoptosis when autophagy was blocked by Bafilomycin A1. These results implied that DNA damage was not directly involved in the autophagy induced by a 0.4mT 50Hz EMF. In addition, an EMF induced autophagy balanced the cellular homeostasis to protect the cells from severe adverse biological consequences.

  19. Aerosol absorption measurement with a sinusoidal phase modulating fiber optic photo thermal interferometer

    Science.gov (United States)

    Li, Shuwang; Shao, Shiyong; Mei, Haiping; Rao, Ruizhong

    2016-10-01

    Aerosol light absorption plays an important role in the earth's atmosphere direct and semi-direct radiate forcing, simultaneously, it also has a huge influence on the visibility impairment and laser engineering application. Although various methods have been developed for measuring aerosol light absorption, huge challenge still remains in precision, accuracy and temporal resolution. The main reason is that, as a part of aerosol light extinction, aerosol light absorption always generates synchronously with aerosol light scattering, and unfortunately aerosol light scattering is much stronger in most cases. Here, a novel photo-thermal interferometry is proposed only for aerosol absorption measurement without disturbance from aerosol scattering. The photo-thermal interferometry consists of a sinusoidal phase-modulating single mode fiber-optic interferometer. The thermal dissipation, caused by aerosol energy from photo-thermal conversion when irritated by pump laser through interferometer, is detected. This approach is completely insensitive to aerosol scattering, and the single mode fiber-optic interferometer is compact, low-cost and insensitive to the polarization shading. The theory of this technique is illustrated, followed by the basic structure of the sinusoidal phase-modulating fiber-optic interferometer and demodulation algorithms. Qualitative and quantitative analysis results show that the new photo-thermal interference is a potential approach for aerosol absorption detection and environmental pollution detection.

  20. Response of autaptic Hodgkin-Huxley neuron with noise to subthreshold sinusoidal signals

    Science.gov (United States)

    Wang, Hengtong; Chen, Yong

    2016-11-01

    In this work, we investigated the response of a stochastic Hodgkin-Huxley (HH) neuron with an autapse to subthreshold sinusoidal signals. It is found that the autapse not only adjusts the stochastic responses, but also improves the detection of subthreshold signals. In the case of weak noise, the autapse facilitates the response of neuron to the subthreshold sinusoidal signals with a small parameter region in tdelay- ω space. The increased noise intensity enlarges this parameter region and increases the corresponding response frequency in such range. As the autaptic intensity increases, however, this parameter region shrunks. We also observed that there is an optimal range of the delay time of autapse, within which the stochastic HH neuron fires action potentials with high frequency. The corresponding response spike train for the optimal delay time is nearly a regular sequence with the interspike intervals approximated to the delay time. The current results reveal a novel resonance phenomenon facilitated by autapse, named autaptic delay-induced coherence resonance.

  1. Measuring the 3D shape of high temperature objects using blue sinusoidal structured light

    Science.gov (United States)

    Zhao, Xianling; Liu, Jiansheng; Zhang, Huayu; Wu, Yingchun

    2015-12-01

    The visible light radiated by some high temperature objects (less than 1200 °C) almost lies in the red and infrared waves. It will interfere with structured light projected on a forging surface if phase measurement profilometry (PMP) is used to measure the shapes of objects. In order to obtain a clear deformed pattern image, a 3D measurement method based on blue sinusoidal structured light is proposed in this present work. Moreover, a method for filtering deformed pattern images is presented for correction of the unwrapping phase. Blue sinusoidal phase-shifting fringe pattern images are projected on the surface by a digital light processing (DLP) projector, and then the deformed patterns are captured by a 3-CCD camera. The deformed pattern images are separated into R, G and B color components by the software. The B color images filtered by a low-pass filter are used to calculate the fringe order. Consequently, the 3D shape of a high temperature object is obtained by the unwrapping phase and the calibration parameter matrixes of the DLP projector and 3-CCD camera. The experimental results show that the unwrapping phase is completely corrected with the filtering method by removing the high frequency noise from the first harmonic of the B color images. The measurement system can complete the measurement in a few seconds with a relative error of less than 1 : 1000.

  2. Nonlinear properties of medial entorhinal cortex neurons reveal frequency selectivity during multi-sinusoidal stimulation.

    Directory of Open Access Journals (Sweden)

    Christophe eMagnani

    2014-08-01

    Full Text Available The neurons in layer II of the medial entorhinal cortex are part of the grid cell network involved in the representation of space. Many of these neurons are likely to be stellate cells with specific oscillatory and firing properties important for their function. A fundamental understanding of the nonlinear basis of these oscillatory properties is critical for the development of theories of grid cell firing. In order to evaluate the behavior of stellate neurons, measurements of their quadratic responses were used to estimate a second order Volterra kernel. This paper uses an operator theory, termed quadratic sinusoidal analysis (QSA, which quantitatively determines that the quadratic response accounts for a major part of the nonlinearity observed at membrane potential levels characteristic of normal synaptic events. Practically, neurons were probed with multi-sinusoidal stimulations to determine a Hermitian operator that captures the quadratic function in the frequency domain. We have shown that the frequency content of the stimulation plays an important role in the characteristics of the nonlinear response, which can distort the linear response as well. Stimulations with enhanced low frequency amplitudes evoked a different nonlinear response than broadband profiles. The nonlinear analysis was also applied to spike frequencies and it was shown that the nonlinear response of subthreshold membrane potential at resonance frequencies near the threshold is similar to the nonlinear response of spike trains.

  3. Minimum entropy deconvolution optimized sinusoidal synthesis and its application to vibration based fault detection

    Science.gov (United States)

    Li, Gang; Zhao, Qing

    2017-03-01

    In this paper, a minimum entropy deconvolution based sinusoidal synthesis (MEDSS) filter is proposed to improve the fault detection performance of the regular sinusoidal synthesis (SS) method. The SS filter is an efficient linear predictor that exploits the frequency properties during model construction. The phase information of the harmonic components is not used in the regular SS filter. However, the phase relationships are important in differentiating noise from characteristic impulsive fault signatures. Therefore, in this work, the minimum entropy deconvolution (MED) technique is used to optimize the SS filter during the model construction process. A time-weighted-error Kalman filter is used to estimate the MEDSS model parameters adaptively. Three simulation examples and a practical application case study are provided to illustrate the effectiveness of the proposed method. The regular SS method and the autoregressive MED (ARMED) method are also implemented for comparison. The MEDSS model has demonstrated superior performance compared to the regular SS method and it also shows comparable or better performance with much less computational intensity than the ARMED method.

  4. Quantification of metallic iodides in fucus vesiculosus and serratus heated at 80 deg, 550 deg and 1 000 deg; Quantification des iodures metalliques dans des cendres d'algues. Analyse de fucus vesiculosus et serratus chauffees a 80 degres, 550 degre et 1000 degre

    Energy Technology Data Exchange (ETDEWEB)

    Aujollet, Y. [Direction Generale de la Surete Nucleaire et de la Radioprotection (DGSNR), 75 - Paris (France)

    2004-02-01

    Metallic iodides in aqueous phase of Fucus ashes were measured by gamma spectrometry. Before the measurements, different samples of Fucus were heated at 80 deg C (Fucus vesiculosus), 550 deg C (Fucus serratus) and 1 000 deg C (Fucus serratus). The first results gave 63% of iodide salts in Fucus vesiculosus heated at 80 deg C, 27% of iodide salts in Fucus serratus (550 deg C) and no result for ashes of Fucus serratus heated at 1 000 deg C, because there was not enough mass of product for a good analysis by gamma spectrometry. (author)

  5. Resistance, capacitance, and electrode kinetic effects in Fourier-transformed large-amplitude sinusoidal voltammetry: emergence of powerful and intuitively obvious tools for recognition of patterns of behavior.

    Science.gov (United States)

    Sher, Anna A; Bond, Alan M; Gavaghan, David J; Harriman, Kathryn; Feldberg, Stephen W; Duffy, Noel W; Guo, Si-Xuan; Zhang, Jie

    2004-11-01

    Large-amplitude sinusoidal ac voltammetric techniques, when analyzed in the frequency domain using the Fourier transform-inverse Fourier transform sequence, produce the expected dc and fundamental harmonic ac responses in addition to very substantial second, third, and higher ac harmonics that arise from the presence of significant nonlinearity. A full numerical simulation of the process, Red right arrow over left arrow Ox + e(-), incorporates terms for the uncompensated resistance (R(u)), capacitance of the double layer (C(dl)), and slow electron transfer kinetics (in particular, the reversible potential (E degrees ), rate constant (k(0)), and charge transfer coefficient (alpha) from the Butler-Volmer model). Identification of intuitively obvious patterns of behavior (with characteristically different sensitivity regimes) in dc, fundamental, and higher harmonic terms enables simple protocols to be developed to estimate R(u), C(dl), E degrees , k(0), and alpha. Thus, if large-amplitude sinusoidal cyclic voltammograms are obtained for two concentrations of the reduced species, data obtained from analysis of the recovered signals provide initial estimates of parameters as follows: (a) the dc cyclic component provides an estimate of E degrees (because the R(u) and k(0) effects are minimized); (b) the fundamental harmonic provides an estimate of C(dl) (because it has a high capacitance-to-faradaic current ratio); and (c) the second harmonic provides an estimate of R(u), k(0), and alpha (because the C(dl) effect is minimized). Methods of refining the initial estimates are then implemented. As a check on the fidelity of the parameters (estimated on the basis of an essentially heuristic approach that solely utilizes the dc, fundamental, and second harmonic voltammograms), comparison of the predicted simulated and experimental third (or higher) harmonic voltammograms can be made to verify that agreement between theory and experiment has been achieved at a predetermined

  6. Analysis and simulation test of RC circuit transient process in sinusoidal excitation signal%正弦信号激励下RC电路暂态过程的分析及仿真测试

    Institute of Scientific and Technical Information of China (English)

    腾香

    2016-01-01

    To systematically study on the transient process of RC first-order circuit under the excitation of the sinusoidal signal, the mathematical expression of the complete response, composed of sinusoidal steady com-ponent superimposing on transient component, is derived from the differential equation of the circuit. The over-voltage phenomenon in transient process occurs due to the existence of transient components and initial phase an-gle conditions of sinusoidal excitation signal for producing maximum overvoltage are analyzed. And then the sim-ulation test is explored with Multisim software.%为了系统地研究正弦信号激励下RC一阶电路的暂态过程,从电路的微分方程出发,推导出电路的完全响应是正弦稳态分量与暂态分量相叠加的数学表达式,暂态分量使电路在暂态过程产生过压现象,分析了产生最大过压时正弦激励信号的初相角条件。并用Multisim软件进行了仿真实验测试。

  7. In situ observations of BrO over Antarctica - ER-2 aircraft results from 54 deg S to 72 deg S latitude

    Science.gov (United States)

    Brune, W. H.; Anderson, J. G.; Chan, K. R.

    1989-01-01

    Bromine monoxide was observed in situ during nine flights of the NASA ER-2 aircraft from Punta Arenas, Chile (54 deg S latitude), to 72 deg S latitude over the Palmer Peninsula, Antarctica. The first flight for the BrO detection system was on August 28. The distribution of BrO inside the chemically perturbed region defined by greatly elevated ClO abundances was different from that found just outside. Inside, the BrO mixing ratio was 6.1 + or - 1.1 pptv above the 440 K potential temperature surface, 4.7 + or - 2.0 pptv between the 400 and 440 K surfaces, and less than 4 pptv below the 400 K surface. At high latitudes outside the chemically perturbed region, the BrO mixing ratio was 5.4 + or - 1.4 pptv near the 450 K surface, but decreased to 2.9 + or - 1.2 pptv at the 420 K surface. The abundance of BrO showed no discernible temporal trend during the course of the nine flights. Away from the south polar region, at latitudes between 47 deg S and 37 deg N and potential temperatures between 435 and 500 K (18.5- to 20.7-km altitude), the BrO mixing ratio was 0.5-3.0 pptv.

  8. Simplified 2DEG carrier concentration model for composite barrier AlGaN/GaN HEMT

    Energy Technology Data Exchange (ETDEWEB)

    Das, Palash, E-mail: d.palash@gmail.com; Biswas, Dhrubes, E-mail: d.palash@gmail.com [Indian Institute of Technology Kharagpur, Kharagpur - 721302, West Bengal (India)

    2014-04-24

    The self consistent solution of Schrodinger and Poisson equations is used along with the total charge depletion model and applied with a novel approach of composite AlGaN barrier based HEMT heterostructure. The solution leaded to a completely new analytical model for Fermi energy level vs. 2DEG carrier concentration. This was eventually used to demonstrate a new analytical model for the temperature dependent 2DEG carrier concentration in AlGaN/GaN HEMT.

  9. Strumentazione multisensore selettiva per il monitoraggio in continuo degli odori nel settore ambientale

    OpenAIRE

    Giuliani, Stefano

    2012-01-01

    2010 - 2011 L’odore indotto dall’esercizio degli impianti di ingegneria sanitaria ambientale è ritenuto la causa principale di disturbo che la popolazione residente nelle vicinanze avverte. Sebbene alle emissioni odorigene sia solo raramente associato un reale rischio tossicologico-sanitario, sia per la natura raramente pericolosa degli odoranti che per le concentrazioni generalmente molto basse, nell’immaginario collettivo, ai cattivi odori si associano spesso condizioni di “non salubrità...

  10. Evaluation of myocardial SPECT imaging reconstructed from 270deg projection data. A study using a cardiac phantom

    Energy Technology Data Exchange (ETDEWEB)

    Kashikura, Kenichi [Japan Science and Technology Corp., Akita (Japan). Akita Lab.; Kobayashi, Hideki; Kashikura, Akemi

    1997-01-01

    SPECT reconstruction is commonly performed using 360deg or 180deg projection data. However, it is also possible to reconstruct SPECT images using other projection data arcs. The purpose of this study was to characterize images obtained by limiting the projection data to 270deg by discarding the projection views with severe attenuation. A series of phantom studies was performed with and without plastic chambers simulating perfusion defects using {sup 201}Tl and {sup 99m}Tc. Images using 270deg, 360deg, and 180deg projection arcs were identically reconstructed from the same data. In the absence of plastic chambers, intraslice uniformity in a given slice was assessed by computing the coefficient of variation (CV) of average counts in 8 ROIs within the slice. Interslice uniformity was assessed by computing the CV of average counts in five short axial slices. With plastic chambers in place, the variability in defect contrasts was assessed by computing the CV of defect contrasts in 4 chambers, located on the anterior, lateral, inferoposterior, and septal walls. The intraslice uniformity of the 270deg images were considerably inferior to those of the 360deg and 180deg images. The interslice uniformity was highest in the 360deg images, and lowest in the 180deg images. The variation in defect contrasts in the 270deg image was higher than those of the other two images. The 270deg images showed a high defect contrast in the septum and high counts in the anterior and anteroseptal wall. Because a large variation in defect contrasts within a segment might result in false positive or negative in diagnosis, 270deg imaging is not recommended over 360deg or 180deg imaging. (author)

  11. NASA Ames Laminar Flow Supersonic Wind Tunnel (LFSWT) Tests of a 10 deg Cone at Mach 1.6

    Science.gov (United States)

    Wolf, Stephen W. D.; Laub, James A.

    1997-01-01

    This work is part of the ongoing qualification of the NASA Ames Laminar Flow Supersonic Wind Tunnel (LFSWT) as a low-disturbance (quiet) facility suitable for transition research. A 10 deg cone was tested over a range of unit Reynolds numbers (Re = 2.8 to 3.8 million per foot (9.2 to 12.5 million per meter)) and angles of incidence (O deg to 10 deg) at Mach 1.6. The location of boundary layer transition along the cone was measured primarily from surface temperature distributions, with oil flow interferometry and Schlieren flow visualization providing confirmation measurements. With the LFSWT in its normal quiet operating mode, no transition was detected on the cone in the test core, over the Reynolds number range tested at zero incidence and yaw. Increasing the pressure disturbance levels in the LFSWT test section by a factor of five caused transition onset on the cone within the test core, at zero incidence and yaw. When operating the LFSWT in its normal quiet mode, transition could only be detected in the test core when high angles of incidence (greater than 5 deg) for cones were set. Transition due to elevated pressure disturbances (Tollmien-Schlichting) and surface trips produced a skin temperature rise of order 4 F (2.2 C). Transition due to cross flows on the leeward side of the cone at incidence produced a smaller initial temperature rise of only order 2.5 F (1.4 C), which indicates a slower transition process. We can conclude that these cone tests add further proof that the LFSWT test core is normally low-disturbance (pressure fluctuations greater than 0.1%), as found by associated direct flow quality measurements discussed in this report. Furthermore, in a quiet test environment, the skin temperature rise is sensitive to the type of dominant instability causing transition. The testing of a cone in the LFSWT provides an excellent experiment for the development of advanced transition detection techniques.

  12. Mesenchymal stem cell-conditioned medium prevents radiation-induced liver injury by inhibiting inflammation and protecting sinusoidal endothelial cells.

    Science.gov (United States)

    Chen, Yi-Xing; Zeng, Zhao-Chong; Sun, Jing; Zeng, Hai-Ying; Huang, Yan-; Zhang, Zhen-Yu

    2015-07-01

    Current management of radiation-induced liver injury is limited. Sinusoidal endothelial cell (SEC) apoptosis and inflammation are considered to be initiating events in hepatic damage. We hypothesized that mesenchymal stem cells (MSCs) possess anti-apoptotic and anti-inflammatory actions during hepatic irradiation, acting via paracrine mechanisms. This study aims to examine whether MSC-derived bioactive components are protective against radiation-induced liver injury in rats. MSC-conditioned medium (MSC-CM) was generated from rat bone marrow-derived MSCs. The effect of MSC-CM on the viability of irradiated SECs was examined by flow cytometric analysis. Activation of the Akt and ERK pathways was analyzed by western blot. MSC-CM was also delivered to Sprague-Dawley rats immediately before receiving liver irradiation, followed by testing for pathological features, changes in serum hyaluronic acid, ALT, and inflammatory cytokine levels, and liver cell apoptosis. MSC-CM enhanced the viability of irradiated SECs in vitro and induced Akt and ERK phosphorylation in these cells. Infusion of MSC-CM immediately before liver irradiation provided a significant anti-apoptotic effect on SECs and improved the histopathological features of injury in the irradiated liver. MSC-CM also reduced the secretion and expression of inflammatory cytokines and increased the expression of anti-inflammatory cytokines. MSC-derived bioactive components could be a novel therapeutic approach for treating radiation-induced liver injury. © The Author 2015. Published by Oxford University Press on behalf of The Japan Radiation Research Society and Japanese Society for Radiation Oncology.

  13. FGL2/fibroleukin mediates hepatic reperfusion injury by induction of sinusoidal endothelial cell and hepatocyte apoptosis in mice.

    Science.gov (United States)

    Selzner, Nazia; Liu, Hao; Boehnert, Markus U; Adeyi, Oyedele A; Shalev, Itay; Bartczak, Agata M; Xue-Zhong, Max; Manuel, Justin; Rotstein, Ori D; McGilvray, Ian D; Grant, David R; Phillips, Melville J; Levy, Gary A; Selzner, Markus

    2012-01-01

    Sinusoidal endothelial cell (SEC) and hepatocyte death are early, TNF-α mediated events in ischemia and reperfusion of the liver (I/Rp). We previously reported that TNF-α induced liver injury is dependent on Fibrinogen like protein 2 (FGL2/Fibroleukin) and showed that FGL2 binding to its receptor, FcγRIIB, results in lymphocyte apoptosis. In this study we examine whether I/Rp is induced by specific binding of FGL2 to FcγRIIB expressed on SEC. Hepatic ischemia and reperfusion was induced in wild type (WT) mice and in mice with deletion or inhibition of FGL2 and FcRIIB. Liver injury was determined by AST release, necrosis and animal death. Apoptosis was evaluated with caspase 3 and TUNEL staining. FGL2 deletion or inhibition resulted in decreased liver injury as determined by a marked reduction in both levels of AST and ALT and hepatocyte necrosis. Caspase 3 staining of SEC (12% vs. 75%) and hepatocytes (12% vs. 45%) as well as TUNEL staining of SEC (13% vs. 60%, p=0.02) and hepatocytes (18% vs. 70%, p=0.03), markers of apoptosis, were lower in Fgl2(-/-) compared to WT mice. In vitro incubation of SEC with FGL2 induced apoptosis of SEC from WT mice, but not FcγRIIB(-/-) mice. Deletion of FcγRIIB fully protected mice against SEC and hepatocyte death in vivo. Survival of mice deficient in either Fgl2(-/-) (80%) or FcγRIIB(-/-) (100%) was markedly increased compared to WT mice (10%) which were subjected to 75min of total hepatic ischemia (p=0.001). FGL2 binding to the FcγRIIB receptor expressed on SEC is a critical event in the initiation of the hepatic reperfusion injury cascade through induction of SEC and hepatocyte death. Copyright © 2011 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.

  14. Expression of MMP-9 in hepatic sinusoidal obstruction syndrome induced by Gynura segetum

    Institute of Scientific and Technical Information of China (English)

    Xia-zhen YU; Tao JI; Xue-li BAI; Liang LIANG; Lin-yan WANG; Wei CHEN; Ting-bo LIANG

    2013-01-01

    Background and objective:Hepatic sinusoidal obstruction syndrome (HSOS) is characterized by painful hepatomegaly,ascites,increased body weight,and jaundice.Gynura segetum (Compositae),a plant widely used in Chinese traditional medicine,often leads to the development of HSOS.However,the mechanism is unclear.The aim was to study the role of matrix metalloproteinase-9 (MMP-9) in the onset of HSOS induced by Gynura segetum.Methods:Twenty-five male Sprague-Dawley rats were randomly divided into two groups.Twenty were exposed to 600 mg/kg daily Gynura segetum extract solution for three weeks; five control rats were exposed to tap water alone.Liver sections were evaluated by light microscopy with a modified scoring system.Routine transmission electron microscopy (TEM) methods were used to evaluate the ultrastructual features of fixed liver tissue,and blood samples were collected to determine liver enzyme concentrations.MMP-9 expression was assessed by both immunohistochemical staining and enzyme-linked immunosorbent assay (ELISA) methods.Results:A stable and reproducible rat model of HSOS was achieved by long-term exposure to Gynura segetum extract.The treated rats presented clinical symptoms and the histopathological manifestation of HSOS,including abnormal liver enzyme concentrations (alanine aminotransferase (ALT):(84.8±13.62) vs.(167.0±72.63) U/L,P<0.05; aspartate aminotransferase (AST):(27.6±6.31)vs.(232.8±108.58) U/L,P<0.05).Hematoxylin and eosin (H&E) staining and TEM together revealed deposition of red blood cells,the damage and destruction of hepatic sinusoidal endothelial cells,collapse of hepatic sinusoids,hemorrhage of subendothelial cells,atrophy and destruction of hepatocytes,etc.Compared with controls,the expression of MMP-9 in the blood sample,the lung and liver tissues of HSOS rats was increased.Conclusions:MMP-9 may have an important role in early pathological changes of HSOS,and thus the onset of the disease.

  15. Human liver sinusoidal endothelial cells promote intracellular crawling of lymphocytes during recruitment: A new step in migration.

    Science.gov (United States)

    Patten, Daniel A; Wilson, Garrick K; Bailey, Dalan; Shaw, Robert K; Jalkanen, Sirpa; Salmi, Marko; Rot, Antal; Weston, Chris J; Adams, David H; Shetty, Shishir

    2017-01-01

    The recruitment of lymphocytes via the hepatic sinusoidal channels and positioning within liver tissue is a critical event in the development and persistence of chronic inflammatory liver diseases. The hepatic sinusoid is a unique vascular bed lined by hepatic sinusoidal endothelial cells (HSECs), a functionally and phenotypically distinct subpopulation of endothelial cells. Using flow-based adhesion assays to study the migration of lymphocytes across primary human HSECs, we found that lymphocytes enter into HSECs, confirmed by electron microscopy demonstrating clear intracellular localization of lymphocytes in vitro and by studies in human liver tissues. Stimulation by interferon-γ increased intracellular localization of lymphocytes within HSECs. Furthermore, using confocal imaging and time-lapse recordings, we demonstrated "intracellular crawling" of lymphocytes entering into one endothelial cell from another. This required the expression of intracellular adhesion molecule-1 and stabilin-1 and was facilitated by the junctional complexes between HSECs.

  16. 2D simulation and analysis of fluid flow between two sinusoidal parallel plates using lattice Bolzmann method

    Directory of Open Access Journals (Sweden)

    Marković Jelena Đ.

    2013-01-01

    Full Text Available In order to obtain a better heat transfer, it is important to enhance fluid mixing in heat exchangers. Since there are negative effects when heat exchangers are operating in turbulent regime (like significant pressure drop, increased size of the pump it is necessary to apply the techniques which would provide better fluid mixing when heat exchangers are operating in laminar regime. Investigations have shown that use of sinusoidal instead of flat plates results in this effect. This study is a result of two dimensional simulation of fluid flow between two parallel sinusoidal plates. Simulation was done with the use of modified Openlb code, based on lattice Boltzmann method. Reynolds number was varied from 200 to 1000, and space between the plates was varied from 3cm to 5 cm. Results showed that sinusoidal plates enhance fluid mixing, especially with greater values of Re and smaller space between the plates, which is in agreement with previous investigations.

  17. Analytical and experimental demonstration of depth of field extension for incoherent imaging system with a standard sinusoidal phase mask

    Institute of Scientific and Technical Information of China (English)

    Hui Zhao; Yingcai Li

    2012-01-01

    The wavefront coding technique is used to enlarge the depth of field (DOF) of incoherent imaging systems.The key to wavefront coding lies in the design of suitable phase masks. To date,numerous kinds of phase masks are proposed.However,further understanding is needed regarding phase mask with its phase function being in a standard sinusoidal form.Therefore,the characteristics of such a phase mask are studied in this letter.Deriving the defocused optical transfer function (OTF) analytically proves that the standard sinusoidal phase mask is effective in extending the DOF,and actual experiments confirm the numerical results.At the same time,with the Fisher information as a criterion,the standard sinusoidal phase mask shows a higher tolerance to focus errors (especially severe focus errors) than the classical cubic phase mask.%The wavefront coding technique is used to enlarge the depth of field (DOF) of incoherent imaging systems. The key to wavefront coding lies in the design of suitable phase masks. To date, numerous kinds of phase masks are proposed. However, further understanding is needed regarding phase mask with its phase function being in a standard sinusoidal form. Therefore, the characteristics of such a phase mask are studied in this letter. Deriving the defocused optical transfer function (OTF) analytically proves that the standard sinusoidal phase mask is effective in extending the DOF, and actual experiments confirm the numerical results. At the same time, with the Fisher information as a criterion, the standard sinusoidal phase mask shows a higher tolerance to focus errors (especially severe focus errors) than the classical cubic phase mask.

  18. Note: Improving low-light-level image detection sensitivity with higher speed using auxiliary sinusoidal light signal

    Science.gov (United States)

    Tang, Hongying; Yu, Zhengtao

    2015-06-01

    An improved active imaging method, which upgraded the detection sensitivity by applying an auxiliary sawtooth wave light signal, was reported. Nevertheless, such method sacrificed the imaging speed. To speed up imaging, a sinusoidal light signal is used instead and superposed with the undetectable low-light-level signal on the image sensor. After acquiring a superimposed image set in one sine wave cycle, an unbiased low-light-level image estimation is obtained by using least-square optimization. Through probabilistic analysis and experimental study, we demonstrate that the sinusoidal signal could improve the detection sensitivity 1/3 faster than the sawtooth wave signal.

  19. Rigorous analysis of the propagation of sinusoidal pulses in bacteriorhodopsin films.

    Science.gov (United States)

    Acebal, Pablo; Blaya, Salvador; Carretero, Luis; Madrigal, R F; Fimia, A

    2012-11-05

    The propagation of sinusoidal pulses in bacteriorhodopsin films has been theoretically analyzed using a complete study of the photoinduced processes that take into account all the physical parameters, the coupling of rate equations with the energy transfer equation and the temperature change during the experiment. The theoretical approach was compared to experimental data and a good concordance was observed. This theoretical treatment, can be widely applied, i.e when arbitrary pump and/or signal is used or in the case of the pump and signal beams have different wavelengths. Due to we have performed a rigorous analysis, from this treatment the corresponding two level approximation has also been analyzed for these systems.

  20. VDCC Based Dual-Mode Quadrature Sinusoidal Oscillator with Outputs at Appropriate Impedance Levels

    Directory of Open Access Journals (Sweden)

    Mayank Srivastava

    2016-01-01

    Full Text Available This article presents a new dual-mode (i.e. both current-mode and voltage-mode quadrature sinusoidal oscillator using two Voltage Differencing Current Conveyors (VDCCs, two resistors and two capacitors. The proposed configuration use only grounded passive elements and enjoys independent resistor/electronic tuning of both Condition of Oscillation (CO as well as Frequency of Oscillation (FO. The quadrature current and voltage mode outputs of this circuit are available at appropriate impedance terminals. The behavior of presented oscillator is also examined under non ideal/parasitic conditions. The validity of the proposed configuration has been confirmed by SPICE simulations with TSMC 0.18μm process parameters.

  1. Laminar heat transfer characteristics of internally finned tube with sinusoidal wavy fin

    Science.gov (United States)

    Lin, M.; Tian, L.; Wang, Q. W.

    2011-06-01

    Comparative numerical study of laminar heat transfer characteristics of annular tubes with sinusoidal wavy fins has been conducted both experimentally and numerically with Re = 299-1,475. The uniform heat flux is imposed on the tube outside wall surface. Two tube materials (copper and stainless steel) are considered. It is found that the fluid temperature profile is not linear but convex along the flow direction due to the axial heat conduction in tube wall, and the effects of axial heat conduction on the heat transfer decreases with an increase in Reynolds number or decrease in tube wall thermal conductivity. The axial distributions of local Nusselt number could reach periodically fully developed after 3-5 cycles. The convectional data reduction method based on the traditional method should be improved for tube with high thermal conductivity or low Reynolds numbers, Otherwise, the heat transfer performance of internally finned tube may be underestimated.

  2. Fiber-optic project-fringe interferometry with sinusoidal phase modulating system

    Science.gov (United States)

    Zhang, Fukai; Duan, Fajie; Lv, Changrong; Duan, Xiaojie; Bo, En; Feng, Fan

    2013-06-01

    A fiber-optic sinusoidal phase-modulating (SPM) interferometer for fringe projection is presented. The system is based on the SPM technique and makes use of the Mach-Zehnder interferometer structure and Young's double pinhole interference principle to achieve interference fringe projection. A Michelson interferometer, which contains the detection of Fresnel reflection on its fiber end face and interference at one input port of a 3 dB coupler, is utilized to achieve feedback precise control of the fringe phase, which is sensitive to phase drifting produced by the nature of the fiber. The phase diversity for the closed-loop SPM system can be real-time measured with a precision of 3 mrad. External disturbances mainly caused by temperature fluctuations can be reduced to 57 mrad for the fringe map. The experimental results have shown the usefulness of the system.

  3. [The analysis of sinusoidal modulated method used for measuring fluorescence lifetime].

    Science.gov (United States)

    Feng, Ying; Huang, Shi-hua

    2007-12-01

    This paper has built a system with a sinusoidal modulated LED as the excitation source. Such exciter was used upon the sample Eu2 L'3 x nH2O (L' = C4H4O4). Both the excitation light and the 5Do-7F2 emission of Eu3+ ion were measured. Fluorescence lifetime, which approximate to 0.680 ms, can then be obtained from the measured excitation and fluorescence waveforms by non-linear least square curve fitting based on the principle of phase-shift measurement of fluorescence lifetime. Data processing methods considering respectively the high order harmonics in the modulation and multi-exponential decay of the fluorescence were discussed. A method of utilizing Fourier series expandedness to amendatory the result was put forward. Accordingly, the applicability for phase-shift method was expanded as well as a more exact result was acquired.

  4. Direct calculation of 2D components of myocardial strain using sinusoidal MR tagging

    Science.gov (United States)

    Osman, Nael F.; Prince, Jerry L.

    1998-07-01

    A new technique to measure local planar strain in left ventricular myocardium using two-dimensional tagged MR images is presented. This new technique is computationally fast, is fully automated, and generates dense motion estimates. It is based on using a 1-1 SPAMM tag pattern which comprise several one-dimensional sinusoidal tag patterns at different frequencies. A local deformation of the myocardium produces a variation in the local frequencies of these patterns, which can be used to compute strain components in the image plane. Local frequency is measured by scanning certain spectral peaks to create complex images, for which the local frequency is the gradient of the angle associated with their complex data points. The method is demonstrated using both simulations and real tagged MR images, and a discussion of these results and of directions for future research is provided.

  5. Attitude control and sloshing suppression for liquid-filled spacecraft in the presence of sinusoidal disturbance

    Science.gov (United States)

    Zhang, Honghua; Wang, Zeguo

    2016-11-01

    The attitude regulation for a liquid-filled spacecraft in the presence of low frequency sinusoidal disturbance is considered in this paper. The liquid-filled spacecraft is modelled as a rigid body attached with a simple pendulum. A novel control scheme is proposed, which is composed of Active Disturbance Rejection Control (ADRC), Positive Position Feedback (PPF), Extended State Observer (ESO) and Singular Spectrum Analysis (SSA). The unknown sloshing mode could be estimated from the combined ESO and SSA, and accordingly ADRC and PPF controller is designed for the stabilization of the spacecraft. Particularly, the parameters of the disturbance are not required as long as its frequency is lower than the sloshing one. The proposed approach could provide stabilization for the spacecraft, rejection for the disturbance, and active damping for the sloshing. Its effectiveness is validated by numerical simulations.

  6. A feedback control system for vibration of magnetostrictive plate subjected to follower force using sinusoidal shear

    Directory of Open Access Journals (Sweden)

    A. Ghorbanpour Arani

    2016-03-01

    Full Text Available In this research, the vibrational behavior of magnetostrictive plate (MsP as a smart component is studied. The plate is subjected to an external follower force and a magnetic field in which the vibration response of MsP has been investigated for both loading combinations. The velocity feedback gain parameter is evaluated to study the effect of magnetic field which is generated by the coil. Sinusoidal shear deformation theory is utilized due to its accuracy of polynomial function with respect to other plate theories. Equations of motion are derived using Hamilton’s principle and solved by differential quadrature method (DQM considering general boundary conditions. The effects of aspect ratio, thickness ratio, follower force and velocity feedback gain are investigated on the frequency response of MsP. Results indicate that magneto-mechanical coupling in MsM helps to control vibrational behaviors of systems such as electro-hydraulic actuator, wireless linear Motors and sensors.

  7. Electrohydrodynamic Nanofluid Hydrothermal Treatment in an Enclosure with Sinusoidal Upper Wall

    Directory of Open Access Journals (Sweden)

    Mohsen Sheikholeslami

    2015-08-01

    Full Text Available The influence of non-uniform electric filed on Fe3O4-Ethylene glycol nanofluid hydrothermal treatment in an enclosure with sinusoidal upper and moving lower walls is investigated in this study. Control Volume based Finite Element Method (CVFEM is utilized to simulate in the presented model. Numerical investigation are conducted for the sundry parameters such as Reynolds number; nanoparticle volume fraction and supplied. Results show that supplied voltage can change the flow shape. Coulomb force causes isotherms denser near the moving wall. Heat transfer rises with augment of supplied voltage and Reynolds number. Effect of electric filed on heat transfer is more pronounced at low Reynolds number. Finally, a comparison with the existing literature is also made.

  8. Sinusoidal hemangioma of the breast: diagnostic evaluation management and literature review

    Science.gov (United States)

    2017-01-01

    Vascular tumors of the breast are rare and may pose a diagnostic challenge. Breast hemangioma is a very rare benign vascular neoplasm accounting for 0.4% of all breast tumors. It is most commonly detected as an incidental microscopic finding in biopsy specimens obtained for unrelated reasons. We describe here a very rare case of a sinusoidal breast hemangioma in a postmenopausal patient who presented with a palpable breast mass. A complete surgical resection was performed because the tumor exhibited atypical imaging features. We conclude that although in carefully selected cases of breast hemangioma a conservative management with follow up imaging is a reasonable option, in cases with atypical imaging or pathological characteristics a complete surgical resection of the vascular tumor is mandatory in order to exclude the possibility of an underlying angiosarcoma. PMID:28210560

  9. Deformation Calculating of Electromagnetic Launcher's Rail Subjected to Sinusoidal Magnetic Pressure

    Directory of Open Access Journals (Sweden)

    Liu Wen

    2011-01-01

    Full Text Available The electromagnetic launcher's rail can be modeled as a beam on elastic foundation with simply supported beam by moving load. In this paper, Euler beam theory is applied to build the mechanical model, and the analytical solution of the equation subjected to sinusoidal magnetic pressure is derived in detail, which has successfully avoided the errors which are caused by using the uniform pressure to approximately replace the variable force. Numerical analysis of the influences brought from the elastic coefficient, the damping coefficient, the mass of rail, and the load's velocity on the deformation of beam by the MATLAB software show that the elastic coefficient and the load's velocity have quite obvious effect on the deformation of the beam while the damping coefficient and the mass of rail have not obvious effect on the deformation of the beam.

  10. Modeling of Electric Disturbance Signals Using Damped Sinusoids via Atomic Decompositions and Its Applications

    Directory of Open Access Journals (Sweden)

    Marco A. M. Rodrigues

    2007-01-01

    Full Text Available The number of waveforms monitored in power systems is increasing rapidly. This creates a demand for computational tools that aid in the analysis of the phenomena and also that allow efficient transmission and storage of the information acquired. In this context, signal processing techniques play a fundamental role. This work is a tutorial reviewing the principles and applications of atomic signal modeling of electric disturbance signals. The disturbance signal is modeled using a linear combination of damped sinusoidal components which are closely related to the phenomena typically observed in power systems. The signal model obtained is then employed for disturbance signal denoising, filtering of “DC components,” and compression.

  11. Exponential sinusoidal model for predicting temperature inside underground wine cellars from a Spanish region

    Energy Technology Data Exchange (ETDEWEB)

    Mazarron, Fernando R.; Canas, Ignacio [Departamento de Construccion y Vias Rurales, Escuela Tecnica Superior de Ingenieros Agronomos, Universidad Politecnica de Madrid, Avda. Complutense s/n, 28040 Madrid (Spain)

    2008-07-01

    This article develops a mathematical model for determining the annual cycle of air temperature inside traditional underground wine cellars in the Spanish region of ''Ribera del Duero'', known because of the quality of its wines. It modifies the sinusoidal analytical model for soil temperature calculation. Results obtained when contrasting the proposed model with experimental data of three subterranean wine cellars for 2 years are satisfactory. The RMSE is below 1 C and the index of agreement is above 0.96 for the three cellars. When using the average of experimental data corresponding to the 2 years' time, results improve noticeably: the RMSE decreases by more than 30% and the mean d reaches 0.99. This model should be a useful tool for designing underground wine cellars making the most of soil energy advantages. (author)

  12. Efficient Maximum Likelihood Estimation of a 2-D Complex Sinusoidal Based on Barycentric Interpolation

    CERN Document Server

    Selva, J

    2011-01-01

    This paper presents an efficient method to compute the maximum likelihood (ML) estimation of the parameters of a complex 2-D sinusoidal, with the complexity order of the FFT. The method is based on an accurate barycentric formula for interpolating band-limited signals, and on the fact that the ML cost function can be viewed as a signal of this type, if the time and frequency variables are switched. The method consists in first computing the DFT of the data samples, and then locating the maximum of the cost function by means of Newton's algorithm. The fact is that the complexity of the latter step is small and independent of the data size, since it makes use of the barycentric formula for obtaining the values of the cost function and its derivatives. Thus, the total complexity order is that of the FFT. The method is validated in a numerical example.

  13. Sensitivity of echo enabled harmonic generation to sinusoidal electron beam energy structure

    Directory of Open Access Journals (Sweden)

    E. Hemsing

    2017-06-01

    Full Text Available We analytically examine the bunching factor spectrum of a relativistic electron beam with sinusoidal energy structure that then undergoes an echo-enabled harmonic generation (EEHG transformation to produce high harmonics. The performance is found to be described primarily by a simple scaling parameter. The dependence of the bunching amplitude on fluctuations of critical parameters is derived analytically, and compared with simulations. Where applicable, EEHG is also compared with high gain harmonic generation (HGHG and we find that EEHG is generally less sensitive to several types of energy structure. In the presence of intermediate frequency modulations like those produced by the microbunching instability, EEHG has a substantially narrower intrinsic bunching pedestal.

  14. Lineage tracing reveals conversion of liver sinusoidal endothelial cells into hepatocytes.

    Science.gov (United States)

    Tan, Zhaoli; Chen, Keyan; Shao, Yong; Gao, Lihua; Wang, Yan; Xu, Jianming; Jin, Yang; Hu, Xianwen; Wang, Youliang

    2016-09-01

    Although liver sinusoidal endothelial cells (LSECs) have long been known to contribute to liver regeneration following injury, the exact role of these cells in liver regeneration remains poorly understood. In this work, we performed lineage tracing of LSECs in mice carrying Tie2-Cre or VE-cadherin-Cre constructs to facilitate fate-mapping of LSECs in liver regeneration. Some YFP-positive LSECs were observed to convert into hepatocytes following a two-thirds partial hepatectomy (PH). Furthermore, human umbilical vein endothelial cells (HUVECs) could be triggered to convert into cells that closely resembled hepatocytes when cultured with serum from mice that underwent an extended PH. These findings suggest that mature non-hepatocyte LSECs play an essential role in mammalian liver regeneration by converting to hepatocytes. The conversion of LSECs to hepatocyte-like (iHep) cells may provide a new approach to tissue engineering.

  15. Single-shot calibration of soft x-ray mirrors using a sinusoidal transmission grating.

    Science.gov (United States)

    Shpilman, Z; Ehrlich, Y; Maman, S; Levy, I; Shussman, T; Oren, G; Zakosky Nueberger, I; Hurvitz, G

    2014-11-01

    Calibration of soft x-ray diagnostics is a challenge due to the lack of laboratory-size calibrated sources. An in situ calibration method for newly developed x-ray mirrors, is presented. The x-ray source is produced by laser-matter interaction, and twin transmission gratings which create two identical dispersion lines. The gratings have a sinusoidal transmission function, which produces a highly precise high-orders free spectrum. An x-ray mirror interacts with one of the dispersion lines, and the mirror efficiency curve as a function of wavelength is extracted. Mirror efficiency shows good agreement with the literature, and evidence of water layer may justify the need of in situ calibration.

  16. Absolute phase recovery in structured light illumination systems: Sinusoidal vs. intensity discrete patterns

    Science.gov (United States)

    Porras-Aguilar, Rosario; Falaggis, Konstantinos

    2016-09-01

    Structured light illumination is a well-established technology for noncontact 3D surface measurements. A common challenge in those systems is to obtain the absolute surface information using few measurement frames. This work discusses techniques based on the projection of multiple sinusoidal fringe patterns with different fringe period, as well as the projection of intensity discrete Gray Code and grey-level coded patterns. The use of sinusoidal multi-frequency techniques has been since years an on-going area of research, where various algorithms have been developed based on beats, look-up tables, or number-theoretical approaches. This work shows that a related technique, the so-called algebraic reconstruction technique that is borrowed from the area of multi-wavelength interferometry can be used for this purpose. This approach provides a robust analytical solution to the phase-unwrapping problem. However, this work argues that despite these advances, the acquisition of additional phase maps obtained with different fringe periods requires too many measurement frames, and hence is inefficient. Motivated by that, this work proposes a new grey level coding scheme that uses only few measurement frames, overcomes typical defocus errors, and has an error detecting feature. The latter feature makes the need of separate error detecting algorithms obsolete. This so-called closed-loop space filling curve can be implemented with an arbitrary number of N grey-levels enabling to code up to (2N) code-words. The performance of this so-called closed-loop space filling curve is demonstrated using experimental data.

  17. Decoupling of excitation and receive coils in pulsed magnetic resonance using sinusoidal magnetic field modulation

    Science.gov (United States)

    Tseytlin, Mark; Epel, Boris; Sundramoorthy, Subramanian; Tipikin, Dmitriy; Halpern, Howard J.

    2016-11-01

    In pulsed magnetic resonance, the excitation power is many orders of magnitude larger than that induced by the spin system in the receiving coil or resonator. The receiver must be protected during and immediately after the excitation pulse to allow for the energy stored in the resonator to dissipate to a safe level. The time during which the signal is not detected, the instrumental dead-time, can be shortened by using magnetically decoupled excitation and receive coils. Such coils are oriented, with respect to each other, in a way that minimizes the total magnetic flux produced by one coil in the other. We suggest that magnetically decoupled coils can be isolated to a larger degree by tuning them to separate frequencies. Spins are excited at one frequency, and the echo signal is detected at another. Sinusoidal magnetic field modulation that rapidly changes the Larmor frequency of the spins between the excitation and detection events is used to ensure the resonance conditions for both coils. In this study, the relaxation times of trityl-CD3 were measured in a field-modulated pulsed EPR experiment and compared to results obtained using a standard spin echo method. The excitation and receive coils were tuned to 245 and 256.7 MHz, respectively. Using an available rapid-scan, cross-loop EPR resonator, we demonstrated an isolation improvement of approximately 20-30 dB due to frequency decoupling. Theoretical analysis, numerical simulations, and proof-of-concept experiments demonstrated that substantial excitation-detection decoupling can be achieved. A pulsed L-band system, including a small volume bi-modal resonator equipped with modulation coils, was constructed to demonstrate fivefold dead-time reduction in comparison with the standard EPR experiment. This was achieved by detuning of the excitation and receive coils by 26 MHz and using sinusoidal modulation at 480 kHz.

  18. Deletion of degQ gene enhances outer membrane vesicle production of Shewanella oneidensis cells.

    Science.gov (United States)

    Ojima, Yoshihiro; Mohanadas, Thivagaran; Kitamura, Kosei; Nunogami, Shota; Yajima, Reiki; Taya, Masahito

    2017-04-01

    Shewanella oneidensis is a Gram-negative facultative anaerobe that can use a wide variety of terminal electron acceptors for anaerobic respiration. In this study, S. oneidensis degQ gene, encoding a putative periplasmic serine protease, was cloned and expressed. The activity of purified DegQ was inhibited by diisopropyl fluorophosphate, a typical serine protease-specific inhibitor, indicating that DegQ is a serine protease. In-frame deletion and subsequent complementation of the degQ were carried out to examine the effect of envelope stress on the production of outer membrane vesicles (OMVs). Analysis of periplasmic proteins from the resulting S. oneidensis strain showed that deletion of degQ induced protein accumulation and resulted in a significant decrease in protease activity within the periplasmic space. OMVs from the wild-type and mutant strains were purified and observed by transmission electron microscopy. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis of the OMVs showed a prominent band at ~37 kDa. Nanoliquid chromatography-tandem mass spectrometry analysis identified three outer membrane porins (SO3896, SO1821, and SO3545) as dominant components of the band, suggesting that these proteins could be used as indices for comparing OMV production by S. oneidensis strains. Quantitative evaluation showed that degQ-deficient cells had a fivefold increase in OMV production compared with wild-type cells. Thus, the increased OMV production following the deletion of DegQ in S. oneidensis may be responsible for the increase in envelope stress.

  19. Precipitation in AISI 316L(N) during creep tests at 550 and 600 deg. C up to 10 years

    Energy Technology Data Exchange (ETDEWEB)

    Padilha, A.F. [University of Sao Paulo , Department of Metallurgical and Materials Engineering, Av. Prof. Mello Moraes 2463, CEP 05508-900, Sao Paulo (Brazil); Escriba, D.M. [University of Sao Paulo , Department of Metallurgical and Materials Engineering, Av. Prof. Mello Moraes 2463, CEP 05508-900, Sao Paulo (Brazil); Materna-Morris, E. [Forschungszentrum Karlsruhe, Institut fuer Materialforschung I, P.O. Box 3640, 76021 Karlsruhe (Germany)]. E-mail: materna-morris@imf.fzk.de; Rieth, M. [Forschungszentrum Karlsruhe, Institut fuer Materialforschung I, P.O. Box 3640, 76021 Karlsruhe (Germany); Klimenkov, M. [Forschungszentrum Karlsruhe, Institut fuer Materialforschung I, P.O. Box 3640, 76021 Karlsruhe (Germany)

    2007-05-15

    The precipitation behaviour in the gauge lengths and in the heads of initially solution annealed type 316L(N) austenitic stainless steel specimens tested in creep at 550 and 600 deg. C for periods of up to 85 000 h has been studied using several metallographic techniques. Three phases were detected: M{sub 23}C{sub 6}, Laves, and sigma phase. The volume fraction of the precipitated sigma phase was significantly higher than that of carbides and the Laves phase. M{sub 23}C{sub 6} carbide precipitation occurred very rapidly and was followed by the sigma and Laves phases formation in the delta ferrite islands. Sigma and Laves phases precipitated at grain boundaries after longer times. Two different mechanisms of sigma phase precipitation have been proposed, one for delta ferrite decomposition and another for grain boundary precipitation. Small quantities of the Laves phase were detected in delta ferrite, at grain boundaries and inside the grains.

  20. Experimental investigation of dielectric barrier discharge plasma actuators driven by repetitive high-voltage nanosecond pulses with dc or low frequency sinusoidal bias

    Science.gov (United States)

    Opaits, Dmitry F.; Likhanskii, Alexandre V.; Neretti, Gabriele; Zaidi, Sohail; Shneider, Mikhail N.; Miles, Richard B.; Macheret, Sergey O.

    2008-08-01

    Experimental studies were conducted of a flow induced in an initially quiescent room air by a single asymmetric dielectric barrier discharge driven by voltage waveforms consisting of repetitive nanosecond high-voltage pulses superimposed on dc or alternating sinusoidal or square-wave bias voltage. To characterize the pulses and to optimize their matching to the plasma, a numerical code for short pulse calculations with an arbitrary impedance load was developed. A new approach for nonintrusive diagnostics of plasma actuator induced flows in quiescent gas was proposed, consisting of three elements coupled together: the schlieren technique, burst mode of plasma actuator operation, and two-dimensional numerical fluid modeling. The force and heating rate calculated by a plasma model was used as an input to two-dimensional viscous flow solver to predict the time-dependent dielectric barrier discharge induced flow field. This approach allowed us to restore the entire two-dimensional unsteady plasma induced flow pattern as well as characteristics of the plasma induced force. Both the experiments and computations showed the same vortex flow structures induced by the actuator. Parametric studies of the vortices at different bias voltages, pulse polarities, peak pulse voltages, and pulse repetition rates were conducted experimentally. The significance of charge buildup on the dielectric surface was demonstrated. The charge buildup decreases the effective electric field in the plasma and reduces the plasma actuator performance. The accumulated surface charge can be removed by switching the bias polarity, which leads to a newly proposed voltage waveform consisting of high-voltage nanosecond repetitive pulses superimposed on a high-voltage low frequency sinusoidal voltage. Advantages of the new voltage waveform were demonstrated experimentally.

  1. Phosphorylated DegU Manipulates Cell Fate Differentiation in the Bacillus subtilis Biofilm

    Science.gov (United States)

    Marlow, Victoria L.; Porter, Michael; Hobley, Laura; Kiley, Taryn B.; Swedlow, Jason R.; Davidson, Fordyce A.

    2014-01-01

    Cell differentiation is ubiquitous and facilitates division of labor and development. Bacteria are capable of multicellular behaviors that benefit the bacterial community as a whole. A striking example of bacterial differentiation occurs throughout the formation of a biofilm. During Bacillus subtilis biofilm formation, a subpopulation of cells differentiates into a specialized population that synthesizes the exopolysaccharide and the TasA amyloid components of the extracellular matrix. The differentiation process is indirectly controlled by the transcription factor Spo0A that facilitates transcription of the eps and tapA (tasA) operons. DegU is a transcription factor involved in regulating biofilm formation. Here, using a combination of genetics and live single-cell cytological techniques, we define the mechanism of biofilm inhibition at high levels of phosphorylated DegU (DegU∼P) by showing that transcription from the eps and tapA promoter regions is inhibited. Data demonstrating that this is not a direct regulatory event are presented. We demonstrate that DegU∼P controls the frequency with which cells activate transcription from the operons needed for matrix biosynthesis in favor of an off state. Subsequent experimental analysis led us to conclude that DegU∼P functions to increase the level of Spo0A∼P, driving cell fate differentiation toward the terminal developmental process of sporulation. PMID:24123822

  2. Simulation of creep test on 316FR stainless steel in sodium environment at 550degC

    Energy Technology Data Exchange (ETDEWEB)

    Satmoko, A. [National Atomic Energy Agency, BATAN (Indonesia); Asayama, Tai

    1999-04-01

    In sodium environment, material 316FR stainless steel risks to suffer from carburization. In this study, an analysis using a Fortran program is conducted to evaluate the carbon influence on the creep behavior of 316FR based on experimental results from uni-axial creep test that had been performed at temperature 550degC in sodium environment simulating Fast Breeder Reactor condition. As performed in experiments, two parts are distinguished. At first, elastic-plastic behavior is used to simulate the fact that just before the beginning of creep test, specimen suffers from load or stress much higher than initial yield stress. In second part, creep condition occurs in which the applied load is kept constant. The plastic component should be included, since stresses increase due to section area reduction. For this reason, elastic-plastic-creep behavior is considered. Through time carbon penetration occurs and its concentration is evaluated empirically. This carburization phenomena are assumed to affect in increasing yield stress, decreasing creep strain rate, and increasing creep rupture strength of material. The model is capable of simulating creep test in sodium environment. Material near from surface risks to be carburized. Its material properties change leading to non-uniform distribution of stresses. Those layers of material suffer from stress concentration, and are subject to damage. By introducing a damage criteria, crack initialization can thus be predicted. And even, crack growth can be evaluated. For high stress levels, tensile strength criterion is more important than creep damage criterion. But in low stress levels, the latter gives more influence in fracture. Under high stress, time to rupture of a specimen in sodium environment is shorter than in air. But for stresses lower than 26 kgf/mm{sup 2}, the time to rupture of creep in sodium environment is the same or little longer than in air. Quantitatively, the carburization effect at 550degC is not important

  3. The Structure of Dark Molecular Gas in the Galaxy - I: A Pilot Survey for 18-cm OH Emission Towards $l \\approx 105^{\\deg}, b \\approx +1^{\\deg}$

    CERN Document Server

    Allen, Ronald J; Engelke, Philip D

    2015-01-01

    We report the first results from a survey for 1665, 1667, and 1720 MHz OH emission over a small region of the Outer Galaxy centered at $l \\approx 105.0\\deg , b \\approx +1.0\\deg$ . This sparse, high-sensitivity survey ($\\Delta Ta \\approx \\Delta Tmb \\approx 3.0 - 3.5$ mK rms in 0.55 km/s channels), was carried out as a pilot project with the Green Bank Telescope (GBT, FWHM $\\approx 7.6'$) on a 3 X 9 grid at $0.5\\deg$ spacing. The pointings chosen correspond with those of the existing $^{12}$CO(1-0) CfA survey of the Galaxy (FWHM $\\approx 8.4'$). With 2-hr integrations, 1667 MHz OH emission was detected with the GBT at $\\gtrsim 21$ of the 27 survey positions ($\\geq 78\\%$ ), confirming the ubiquity of molecular gas in the ISM as traced by this spectral line. With few exceptions, the main OH lines at 1665 and 1667 MHz appear in the ratio of 5:9 characteristic of LTE at our sensitivity levels. No OH absorption features are recorded in the area of the present survey, in agreement with the low levels of continuum bac...

  4. Analysis of the thin layer of Galactic warm ionized gas in the range 20 < l < 30 deg, -1.5 < b < +1.5 deg

    CERN Document Server

    Paladini, R; Davies, R D; Giard, M

    2005-01-01

    We present an analysis of the thin layer of Galactic warm ionized gas at an angular resolution ~ 10'. This is carried out using radio continuum data at 1.4 GHz, 2.7 GHz and 5 GHz in the coordinate region 20 < l < 30 deg, -1.5 < b < +1.5 deg. For this purpose, we evaluate the zero level of the 2.7 and 5 GHz surveys using auxiliary data at 2.3 GHz and 408 MHz. The derived zero level corrections are T_{zero}(2.7 GHz)=0.15 +/- 0.06 K and T_{zero}(5 GHz)=0.1 +/- 0.05 K. We separate the thermal (free-free) and non-thermal (synchrotron) component by means of a spectral analysis performed adopting an antenna temperature spectral index -2.1 for the free-free emission, a realistic spatial distribution of indices for the synchrotron radiation and by fitting, pixel-by-pixel, the Galactic spectral index. We find that at 5 GHz, for |b| = 0 deg, the fraction of thermal emission reaches a maximum value of 82%, while at 1.4 GHz, the corresponding value is 68%. In addition, for the thermal emission, the analysis in...

  5. SAS-2 observations of the diffuse gamma radiation in the galactic latitude interval 10 deg absolute b or equal to 90 deg

    Science.gov (United States)

    Fichtel, C. E.; Hartman, R. C.; Kniffen, D. A.; Thompson, D. J.; Oegelman, H. B.; Oezel, M. E.; Tuemer, T.

    1977-01-01

    An analysis of all of the second small astronomy satellite gamma-ray data for galactic latitudes with the absolute value of b 10 deg has shown that the intensity varies with galactic latitude, being larger near 10 deg than 90 deg. For energies above 100 MeV the gamma-ray data are consistent with a latitude distribution of the form I(b) = C sub 1 + C sub 2/sin b, with the second term being dominant. This result suggests that the radiation above 100 MeV is coming largely from local regions of the galactic disk. Between 35 and 100 MeV, a similar equation is also a good representation of the data, but here the two terms are comparable. These results indicate that the diffuse radiation above 35 MeV consists of two parts, one with a relatively hard galactic component and the other an isotropic, steep spectral component which extrapolates back well to the low energy diffuse radiation. The steepness of the diffuse isotropic component places significant constraints on possible theoretical models of this radiation.

  6. Sinusoidal stimulation trains suppress epileptiform spikes induced by 4-AP in the rat hippocampal CA1 region in-vivo.

    Science.gov (United States)

    Zheshan Guo; Zhouyan Feng; Ying Yu; Wenjie Zhou; Zhaoxiang Wang; Xuefeng Wei

    2016-08-01

    Deep brain stimulation (DBS) shows promises in the treatment of refractory epilepsy. Due to the complex causes of epilepsy, the mechanisms of DBS are still unclear. Depolarization block caused by the persistent excitation of neurons may be one of the possible mechanisms. To test the hypothesis, 4-aminopyridine (4-AP) was injected in rat hippocampal CA1 region in-vivo to induce epileptiform activity. Sinusoidal stimulation trains were applied to the afferent pathway (Schaffer collaterals) of CA1 region to suppress the epileptiform spikes. Results show that 2-min long trains of sinusoidal stimulation (50 Hz) decreased the firing rate of population spikes (PS) and decreased the PS amplitudes significantly. In addition, small positive sharp waves replaced PS activity during the periods of stimulation. A lower frequency sinusoidal stimulation (10 Hz) failed to decrease the firing rate of PS, but decreased the PS amplitudes significantly. These results suggest that stimulation trains of sinusoidal waves could suppress epileptiform spikes. Presumably, the stimulation with a high enough frequency might excite the downstream neurons persistently and elevate the membrane potentials continuously, thereby cause depolarization blocks in the neurons. The findings of the study provide insights in revealing the mechanisms of DBS, and have important implications to the clinical treatment of epilepsy.

  7. Using composite sinusoidal patterns in structured-illumination reflectance imaging (SIRI) for enhanced detection of defects in food

    Science.gov (United States)

    This study presented a first exploration of using composite sinusoidal patterns that integrated two and three spatial frequencies of interest, in structured-illumination reflectance imaging (SIRI) for enhanced detection of defects in food (e.g., bruises in apples). Three methods based on Fourier tra...

  8. On the Fully-Developed Heat Transfer Enhancing Flow Field in Sinusoidally, Spirally Corrugated Tubes Using Computational Fluid Dynamics

    DEFF Research Database (Denmark)

    Hærvig, Jakob; Sørensen, Kim; Condra, Thomas Joseph

    2017-01-01

    A numerical study has been carried out to investigate heat transfer enhancing flow field in 28 geometrically different sinusoidally, spirally corrugated tubes. To vary the corrugation, the height of corrugation e/De/D and the length between two successive corrugated sections p/Dp/D are varied in ...

  9. 50 Hz-Sinusoidal magnetic field induced effects on the bioelectric activity of single unit neurone cells

    Science.gov (United States)

    Azanza, María. J.; Calvo, Ana C.; del Moral, A.

    2001-05-01

    Neurones recruiting and synchronized bioelectric activity recorded from Helix aspersa brain ganglia, under exposure to 50 Hz sinusoidal magnetic fields of 1-15 mT intensity, is reported. We show recruiting responses from single neurones and the synchronization of pairs of neurones activity. Experimental evidence and model theoretical explanation for the spreading of synchronization are presented.

  10. Research on a new magnetic-field-modulated brushless double-rotor machine with sinusoidal-permeance modulating ring

    Directory of Open Access Journals (Sweden)

    Ping Zheng

    2017-05-01

    Full Text Available The magnetic-field-modulated brushless double-rotor machine (MFM-BDRM, composed of a stator, a modulating ring rotor, and a PM rotor, is a kind of power-split device for hybrid electric vehicles (HEVs. In this paper, a new MFM-BDRM with sinusoidal-permeance modulating ring named Sinusoidal-Permeance-Modulating-Ring Brushless Double-Rotor Machine (SPMR-BDRM is proposed to solve the problem of poor mechanical strength and large iron loss. The structure and the operating principle of the MFM-BDRM are introduced. The design principle of the sinusoidal-permeance modulating ring is analyzed and derived. The main idea of that is to minimize the harmonic permeance of air gap, thereby the harmonic magnetic fields can be restrained. There are comparisons between a MFM-BDRM with sinusoidal-permeance modulating ring and a same size MFM-BDRM with traditional modulating ring, including magnetic field distributions and electromagnetic performances. Most importantly, the iron losses are compared under six different conditions. The result indicates that the harmonic magnetic fields in the air gap are restrained; the electromagnetic torque and power factor are almost the same with same armature current; the torque ripples of the modulating ring rotor and the PM rotor are reduced; the stator loss is reduced by 13% at least and the PM loss is reduced by 20% at least compared with the same size traditional MFM-BDRM under the same operating conditions.

  11. Electrical spin injection and detection in high mobility 2DEG systems

    Science.gov (United States)

    Ciorga, M.

    2016-11-01

    In this review paper we present the current status of research related to the topic of electrical spin injection and detection in two-dimensional electron gas (2DEG) systems, formed typically at the interface between two III-V semiconductor compounds. We discuss both theoretical aspects of spin injection in case of ballistic transport as well as give an overview of available reports on spin injection experiments performed on 2DEG structures. In the experimental part we focus particularly on our recent work on all-semiconductor structures with a 2DEG confined at an inverted GaAs/(Al,Ga)As interface and with a ferromagnetic semiconductor (Ga,Mn)As employed as a source of spin-polarized electrons.

  12. Ten deg off-axis tensile test for intralaminar shear characterization of fiber composites

    Science.gov (United States)

    Chamis, C. C.; Sinclair, J. H.

    1976-01-01

    A combined theoretical and experimental investigation was conducted to assess the suitability of the 10 deg off-axis tensile test specimen for the intralaminar shear characterization of unidirectional composites. Composite mechanics, a combined-stress failure criterion, and a finite element analysis were used to determine theoretically the stress-strain variation across the specimen width and the relative stress and strain magnitudes at the 10 deg plane. Strain gages were used to measure the strain variation across the specimen width at specimen midlength and near the end tabs. Specimens from Mod-I/epoxy, T-300/epoxy, and S-glass/epoxy were used in the experimental program. It was found that the 10 deg off-axis tensile test specimen is suitable for intralaminar shear characterization and it is recommended that it should be considered as a possible standard test specimen for such a characterization.

  13. Giovanni Degli Alessandri: i primi anni del direttorato agli Uffizi fra nuovi e vecchi ruoli

    Directory of Open Access Journals (Sweden)

    Chiara Pasquinelli

    2011-11-01

    Full Text Available La figura di Giovanni Degli Alessandri (1765-1830, presidente dell’Accademia di Belle Arti di Firenze e direttore degli Uffizi tra gli anni napoleonici e la Restaurazione di Ferdinando III d’Asburgo-Lorena, è quella di un personaggio chiave nella politica artistica fiorentina, e toscana più in generale. Nel saggio si esaminano i primi anni del suo direttorato alla Galleria, i rapporti con Antonio Canova, il suo ruolo all’interno dell’entourage di Elisa Baciocchi Bonaparte, oltre a considerare alcuni spunti legati al rinnovamento degli Uffizi, nonché la delicata vicenda del passaggio in città di Dominique-Vivant Denon, direttore del Louvre. L’obbiettivo è quello di introdurre elementi di approfondimento relativamente a una figura molto nota ma poco studiata.

  14. A high sensitivity HI survey of the sky at delta < -25 deg Final data release

    CERN Document Server

    Bajaja, E; Larrarte, J J; Morras, R; Poppel, W G L; Kalberla, P M W

    2005-01-01

    We present the final data release of the high sensitivity lambda 21-cm neutral hydrogen survey of the sky south of delta < -25 degr. A total of 50980 positions lying on a galactic coordinate grid with points spaced by (Delta l, Delta b) = ((0.5 deg)/cos b, 0.5 deg) were observed with the 30-m dish of the Instituto Argentino de Radioastronomia (IAR). The angular resolution of the survey is HPBW = 0.5 deg and the velocity coverage spans the interval -450 km/s to +400 km/s (LSR). The velocity resolution is 1.27 km/s and the final rms noise of the entire database is 0.07 K. The data are corrected for stray radiation and converted to brightness temperatures.

  15. Reclutamento e formazione dei poliziotti: il caso degli ufficiali della gendarmeria francese

    Directory of Open Access Journals (Sweden)

    François Dieu

    2007-04-01

    Full Text Available Partendo dal caso degli ufficiali della gendarmeria francese, questo articolo illustra il modo in cui il reclutamento e la formazione possono contribuire, informalmente, alla ripartizione del potere nelle organizzazioni di polizia. Tramite la diversità delle vie di reclutamento si costituisce, di fatto, un vero e proprio sistema di "caste", con una stratificazione degli ufficiali in tre livelli gerarchici, che produce, al di là dei principi meritocratici, delle ineguaglianze manifeste nella ripartizione del potere nell'organizzazione della gendarmeria.

  16. Additive Effects of Sinusoidal Lower Body Negative Pressure on Cardiovascular Responses.

    Science.gov (United States)

    Ishibashi, Keita; Oyama, Fuyuki; Yoshida, Hisao; Iwanaga, Koichi

    2017-02-01

    Sinusoidal lower body negative pressure (SLBNP) has been used to investigate the cardiovascular response to slow periodic changes in blood shifts, but measurements of slow fluctuations take a long time if measured for each period of SLBNP separately. Our study aimed to investigate whether the cardiovascular responses to superimposed SLBNP (S-SLBNP), which is expected to reduce the measurement time, are different from responses measured individually. S-SLBNP was configured by superimposing two conventional SLBNPs (C-SLBNP) at 180-s and 30-s periods in the pressure range from 0 to -25 mmHg. As the S-SLBNP has double the static load of C-SLBNP, we also used offset SLBNP (O-SLBNP), which has the same static load level as S-SLBNP. Heart rate (HR), thoracic impedance (Z0), and mean arterial pressure (MAP) were measured from 11 male subjects. The transfer functions of gains from MAP to HR (Gain-HR/MAP) and from Z0 to HR (Gain-HR/Z0) were calculated as indexes of arterial baroreflex and cardiopulmonary baroreflex regulation of HR, respectively. The Gain-HR/MAP in the 180-s period (2.11 ± 0.17 bpm/mmHg; mean ± SEM) was larger than that of the 30-s period (1.04 ± 0.09 bpm/mmHg); however, there was no significant difference between the SLBNP conditions. The Gain-HR/Z0 in C-SLBNP (9.37 ± 1.47 bpm/ohm) was smaller than that of the other conditions [18.46 ± 2.45 bpm/ohm (O-SLBNP); 16.09 ± 2.29 bpm/ohm (S-SLBNP)]. Using S-SLBNP could reduce the measurement time needed to examine the arterial baroreflex. However, the cardiopulmonary baroreflex was modified by the static load of SLBNP.Ishibashi K, Oyama F, Yoshida H, Iwanaga K. Additive effects of sinusoidal lower body negative pressure on cardiovascular responses. Aerosp Med Hum Perform. 2017; 88(2):137-141.

  17. Free cholesterol accumulation in liver sinusoidal endothelial cells exacerbates acetaminophen hepatotoxicity via TLR9 signaling.

    Science.gov (United States)

    Teratani, Toshiaki; Tomita, Kengo; Suzuki, Takahiro; Furuhashi, Hirotaka; Irie, Rie; Hida, Shigeaki; Okada, Yoshikiyo; Kurihara, Chie; Ebinuma, Hirotoshi; Nakamoto, Nobuhiro; Saito, Hidetsugu; Hibi, Toshifumi; Miura, Soichiro; Hokari, Ryota; Kanai, Takanori

    2017-05-26

    Although obesity is a risk factor for acute liver failure, the pathogenic mechanisms are not yet fully understood. High cholesterol (HC) intake, which often underlies obesity, is suggested to play a role in the mechanism. We aimed to elucidate the effect of a HC diet on acetaminophen-induced acute liver injury, the most frequent cause of acute liver failure in the USA. C57BL/6 Toll-like receptor 9 (TLR9) knockout (Tlr9(-/-)) mice and their Tlr9(+/+) littermates were fed an HC diet for fourweeks and then treated with acetaminophen. Liver sinusoidal endothelial cells (LSECs) were isolated from the mice for in vivo and in vitro analyses. The HC diet exacerbated acetaminophen-induced acute liver injury in a TLR9/inflammasome pathway-dependent manner. LSECs played a major role in the cholesterol loading-induced exacerbation. The accumulation of free cholesterol in the endolysosomes in LSECs enhanced TLR9-mediated signaling, thereby exacerbating the pathology of acetaminophen-induced liver injury through the activation of the TLR9/inflammasome pathway. The accumulation of free cholesterol in LSEC endolysosomes induced a dysfunction of the Rab7 membrane trafficking recycling mechanism, thus disrupting the transport of TLR9 from late endosomes to the lysosomes. Consequently, the level of active TLR9 in the late endosomes increased, thereby enhancing TLR9 signaling in LSECs. HC intake exaggerated acetaminophen-induced acute liver injury via free cholesterol accumulation in LSECs, demonstrating a novel role of free cholesterol as a metabolic factor in TLR9 signal regulation and pathologies of acetaminophen-induced liver injury. Therapeutic approaches may target this pathway. Lay summary: High cholesterol intake exacerbated acetaminophen-induced acute liver injury via the accumulation of free cholesterol in the endolysosomes of liver sinusoidal endothelial cells. This accumulation enhanced Toll-like receptor 9 signaling via impairment of its membrane trafficking mechanism

  18. Neuronal Oscillations with Non-sinusoidal Morphology Produce Spurious Phase-to-Amplitude Coupling and Directionality

    Science.gov (United States)

    Lozano-Soldevilla, Diego; ter Huurne, Niels; Oostenveld, Robert

    2016-01-01

    Neuronal oscillations support cognitive processing. Modern views suggest that neuronal oscillations do not only reflect coordinated activity in spatially distributed networks, but also that there is interaction between the oscillations at different frequencies. For example, invasive recordings in animals and humans have found that the amplitude of fast oscillations (>40 Hz) occur non-uniformly within the phase of slower oscillations, forming the so-called cross-frequency coupling (CFC). However, the CFC patterns might be influenced by features in the signal that do not relate to underlying physiological interactions. For example, CFC estimates may be sensitive to spectral correlations due to non-sinusoidal properties of the alpha band wave morphology. To investigate this issue, we performed CFC analysis using experimental and synthetic data. The former consisted in a double-blind magnetoencephalography pharmacological study in which participants received either placebo, 0.5 or 1.5 mg of lorazepam (LZP; GABAergic enhancer) in different experimental sessions. By recording oscillatory brain activity with during rest and working memory (WM), we were able to demonstrate that posterior alpha (8–12 Hz) phase was coupled to beta-low gamma band (20–45 Hz) amplitude envelope during all sessions. Importantly, bicoherence values around the harmonics of the alpha frequency were similar both in magnitude and topographic distribution to the cross-frequency coherence (CFCoh) values observed in the alpha-phase to beta-low gamma coupling. In addition, despite the large CFCoh we found no significant cross-frequency directionality (CFD). Critically, simulations demonstrated that a sizable part of our empirical CFCoh between alpha and beta-low gamma coupling and the lack of CFD could be explained by two-three harmonics aligned in zero phase-lag produced by the physiologically characteristic alpha asymmetry in the amplitude of the peaks relative to the troughs. Furthermore, we

  19. Neuronal oscillations with non-sinusoidal morphology produce spurious phase-to-amplitude coupling and directionality.

    Directory of Open Access Journals (Sweden)

    Diego Lozano-Soldevilla

    2016-08-01

    Full Text Available Neuronal oscillations support cognitive processing. Modern views suggest that neuronal oscillations do not only reflect coordinated activity in spatially distributed networks, but also that there is interaction between the oscillations at different frequencies. For example, invasive recordings in animals and humans have found that the amplitude of fast oscillations (> 40 Hz occur non-uniformly within the phase of slower oscillations, forming the so-called cross-frequency coupling (CFC. However, the CFC patterns be influenced by features in the signal that do not relate to underlying physiological interactions. For example, CFC estimates may be sensitive to spectral correlations due to non-sinusoidal properties of the alpha band wave morphology. To investigate this issue, we performed CFC analysis using experimental and synthetic data. The former consisted in a double-blind magnetoencephalography pharmacological study in which participants received either placebo, 0.5 mg or 1.5 mg of lorazepam (LZP; GABAergic enhancer in different experimental sessions. By recording oscillatory brain activity with during rest and working memory (WM, we were able to demonstrate that posterior alpha (8 – 12 Hz phase was coupled to beta-low gamma band (20 – 45 Hz amplitude envelope during all sessions. Importantly, bicoherence values around the harmonics of the alpha frequency were similar both in magnitude and topographic distribution to the cross-frequency coherence (CFCoh values observed in the alpha-phase to beta-low gamma coupling. In addition, despite the large CFCoh we found no significant cross-frequency directionality (CFD. Critically, simulations demonstrated that a sizable part of our empirical CFCoh between alpha and beta-low gamma coupling and the lack of CFD could be explained by two-three harmonics aligned in zero phase-lag produced by the physiologically characteristic alpha asymmetry in the amplitude of the peaks relative to the troughs

  20. Astronomical component estimation (ACE v.1) by time-variant sinusoidal modeling

    Science.gov (United States)

    Sinnesael, Matthias; Zivanovic, Miroslav; De Vleeschouwer, David; Claeys, Philippe; Schoukens, Johan

    2016-09-01

    Accurately deciphering periodic variations in paleoclimate proxy signals is essential for cyclostratigraphy. Classical spectral analysis often relies on methods based on (fast) Fourier transformation. This technique has no unique solution separating variations in amplitude and frequency. This characteristic can make it difficult to correctly interpret a proxy's power spectrum or to accurately evaluate simultaneous changes in amplitude and frequency in evolutionary analyses. This drawback is circumvented by using a polynomial approach to estimate instantaneous amplitude and frequency in orbital components. This approach was proven useful to characterize audio signals (music and speech), which are non-stationary in nature. Paleoclimate proxy signals and audio signals share similar dynamics; the only difference is the frequency relationship between the different components. A harmonic-frequency relationship exists in audio signals, whereas this relation is non-harmonic in paleoclimate signals. However, this difference is irrelevant for the problem of separating simultaneous changes in amplitude and frequency. Using an approach with overlapping analysis frames, the model (Astronomical Component Estimation, version 1: ACE v.1) captures time variations of an orbital component by modulating a stationary sinusoid centered at its mean frequency, with a single polynomial. Hence, the parameters that determine the model are the mean frequency of the orbital component and the polynomial coefficients. The first parameter depends on geologic interpretations, whereas the latter are estimated by means of linear least-squares. As output, the model provides the orbital component waveform, either in the depth or time domain. Uncertainty analyses of the model estimates are performed using Monte Carlo simulations. Furthermore, it allows for a unique decomposition of the signal into its instantaneous amplitude and frequency. Frequency modulation patterns reconstruct changes in

  1. Flow and axial dispersion in a sinusoidal-walled tube: Effects of inertial and unsteady flows

    Science.gov (United States)

    Richmond, Marshall C.; Perkins, William A.; Scheibe, Timothy D.; Lambert, Adam; Wood, Brian D.

    2013-12-01

    In this work, we consider a sinusoidal-walled tube (a three-dimensional tube with sinusoidally-varying diameter) as a simplified conceptualization of flow in porous media. Direct numerical simulation using computational fluid dynamics (CFD) methods was used to compute velocity fields by solving the Navier-Stokes equations, and also to numerically solve the volume averaging closure problem, for a range of Reynolds numbers (Re) spanning the low-Re to inertial flow regimes, including one simulation at Re=449 for which unsteady flow was observed. The longitudinal dispersion observed for the flow was computed using a random walk particle tracking method, and this was compared to the longitudinal dispersion predicted from a volume-averaged macroscopic mass balance using the method of volume averaging; the results of the two methods were consistent. Our results are compared to experimental measurements of dispersion in porous media and to previous theoretical results for both the low-Re, Stokes flow regime and for values of Re representing the steady inertial regime. In the steady inertial regime, a power-law increase in the effective longitudinal dispersion (DL) with Re was found, and this is consistent with previous results. This rapid rate of increase is caused by trapping of solute in expansions due to flow separation (eddies). One unsteady (but non-turbulent) flow case (Re=449) was also examined. For this case, the rate of increase of DL with Re was smaller than that observed at lower Re. Velocity fluctuations in this regime lead to increased rates of solute mass transfer between the core flow and separated flow regions, thus diminishing the amount of tailing caused by solute trapping in eddies and thereby reducing longitudinal dispersion. The observed tailing was further explored through analysis of concentration skewness (third moment) and its assymptotic convergence to conventional advection-dispersion behavior (skewness = 0). The method of volume averaging was

  2. High-resolution micro-CT for morphologic and quantitative assessment of the sinusoid in human cavernous hemangioma of the liver.

    Directory of Open Access Journals (Sweden)

    Jinghao Duan

    Full Text Available Hepatic sinusoid plays a vital role in human cavernous hemangioma of the liver (CHL, and its morphologic investigation facilitates the understanding of microcirculation mechanism and pathological change of CHL. However, precise anatomical view of the hepatic sinusoid has been limited by the resolution and contrast available from existing imaging techniques. While liver biopsy has traditionally been the reliable method for the assessment of hepatic sinusoids, the invasiveness and sampling error are its inherent limitations. In this study, imaging of CHL samples was performed using in-line phase-contrast imaging (ILPCI technique with synchrotron radiation. ILPCI allowed clear visualization of soft tissues and revealed structural details that were invisible to conventional radiography. Combining the computed tomography (CT technique, ILPCI-CT was used to acquire the high-resolution micro-CT images of CHL, and three dimensional (3D microstructures of hepatic sinusoids were provided for the morphologic depiction and quantitative assessment. Our study demonstrated that ILPCI-CT could substantially improve the radiographic contrast of CHL tissues in vitro with no contrast agent. ILPCI-CT yielded high-resolution micro-CT image of CHL sample at the micron scale, corresponding to information on actual structures revealed at histological section. The 3D visualization provided an excellent view of the hepatic sinusoid. The accurate view of individual hepatic sinusoid was achieved. The valuable morphological parameters of hepatic sinusoids, such as thrombi, diameters, surface areas and volumes, were measured. These parameters were of great importance in the evaluation of CHL, and they provided quantitative descriptors that characterized anatomical properties and pathological features of hepatic sinusoids. The results highlight the high degree of sensitivity of the ILPCI-CT technique and demonstrate the feasibility of accurate visualization of hepatic

  3. Sinusoidal Parameter Estimation Using Quadratic Interpolation around Power-Scaled Magnitude Spectrum Peaks

    Directory of Open Access Journals (Sweden)

    Kurt James Werner

    2016-10-01

    Full Text Available The magnitude of the Discrete Fourier Transform (DFT of a discrete-time signal has a limited frequency definition. Quadratic interpolation over the three DFT samples surrounding magnitude peaks improves the estimation of parameters (frequency and amplitude of resolved sinusoids beyond that limit. Interpolating on a rescaled magnitude spectrum using a logarithmic scale has been shown to improve those estimates. In this article, we show how to heuristically tune a power scaling parameter to outperform linear and logarithmic scaling at an equivalent computational cost. Although this power scaling factor is computed heuristically rather than analytically, it is shown to depend in a structured way on window parameters. Invariance properties of this family of estimators are studied and the existence of a bias due to noise is shown. Comparing to two state-of-the-art estimators, we show that an optimized power scaling has a lower systematic bias and lower mean-squared-error in noisy conditions for ten out of twelve common windowing functions.

  4. Application of the bispectrum for detection of small nonlinearities excited sinusoidally

    Science.gov (United States)

    Courtney, C. R. P.; Neild, S. A.; Wilcox, P. D.; Drinkwater, B. W.

    2010-09-01

    The nonlinear behaviour of damaged systems excited by vibration or ultrasound offers potential as a technique for damage detection in machine condition monitoring and non-destructive testing applications. The bispectrum, a third-order spectrum, has properties that lend themselves to the measurement of nonlinearities in systems. The properties of interest are insensitivity to Gaussian noise and ability to detect quadratic phase coupling. However, thus far analysis of the statistics of bispectrum estimation has been mainly aimed at stochastic systems. Many applications to vibration and ultrasound involve primarily deterministic, periodic excitations in the presence of stochastic noise. This paper considers the properties of a bispectrum estimate when applied to a system with weak quadratic nonlinearity excited by the superposition of two sinusoids in the presence of additive Gaussian noise. This is compared, using signal-to-noise ratios, to the powerspectrum, with the results validated using numerical data. Also addressed is the effect of quadratic phase coupling on such a system (in the absence of noise).

  5. 50 Hz sinusoidal magnetic fields do not affect human lymphocyte activation and proliferation in vitro

    Science.gov (United States)

    Capri, Miriam; Mesirca, Pietro; Remondini, Daniel; Carosella, Simona; Pasi, Sara; Castellani, Gastone; Franceschi, Claudio; Bersani, Ferdinando

    2004-12-01

    In the last 30 years, an increasing public concern about the possible harmful effects of electromagnetic fields generated by power lines and domestic appliances has pushed the scientific community to search for a correct and comprehensive answer to this problem. In this work the effects of exposure to 50 Hz sinusoidal magnetic fields, with a magnetic flux density of 0.05 mT and 2.5 mT (peak values), were studied on human peripheral blood mononuclear cells (PBMCs) collected from healthy young and elderly donors. Cell activation and proliferation were investigated by using flow cytometry techniques and 3H-TdR incorporation assays, respectively. The results obtained indicated that exposure to the fields altered neither DNA synthesis nor the capacity of lymphocytes to enter the activation phase and progress into the cell cycle. Thus, the conclusions are that two important functional phases of human lymphocytes, such as activation and proliferation, are not affected by exposures to 50 Hz magnetic fields similar to those found under power lines.

  6. Residual intensity modulation in resonator fiber optic gyros with sinusoidal wave phase modulation

    Institute of Scientific and Technical Information of China (English)

    Di-qing YING; Qiang LI; Hui-lian MA; Zhong-he JIN

    2014-01-01

    We present how residual intensity modulation (RIM) affects the performance of a resonator fiber optic gyro (R-FOG) through a sinusoidal wave phase modulation technique. The expression for the R-FOG system’s demodulation curve under RIM is obtained. Through numerical simulation with different RIM coefficients and modulation frequencies, we find that a zero deviation is induced by the RIM effect on the demodulation curve, and this zero deviation varies with the RIM coefficient and modulation frequency. The expression for the system error due to this zero deviation is derived. Simulation results show that the RIM-induced error varies with the RIM coefficient and modulation frequency. There also exists optimum values for the RIM coefficient and modulation frequency to totally eliminate the RIM-induced error, and the error increases as the RIM coefficient or modulation frequency deviates from its optimum value;however, in practical situations, these two parameters would not be exactly fixed but fluctuate from their respective optimum values, and a large system error is induced even if there exists a very small deviation of these two critical parameters from their optimum values. Simulation results indicate that the RIM-induced error should be con-sidered when designing and evaluating an R-FOG system.

  7. A new model for utricular function testing using a sinusoidal translation profile during unilateral centrifugation.

    Science.gov (United States)

    Buytaert, K I; Nooij, S A E; Neyt, X; Migeotte, P-F; Vanspauwen, R; Van de Heyning, P H; Wuyts, F L

    2010-01-01

    The utricle plays an important role in orientation with respect to gravity. The unilateral centrifugation test allows a side-by-side investigation of both utricles. During this test, the subject is rotated about an earth-vertical axis at high rotation speeds (e.g. 400°/s) and translated along an interaural axis to consecutively align the axis of rotation with the left and the right utricle. A simple sinusoidal translation profile (0.013 Hz; amplitude = 4 cm) was chosen. The combined rotation and translation induces ocular counter rolling (OCR), which is measured using 3-D video-oculography. This OCR is the sum of the reflexes generated by both the semicircular canals and the utricles. In this paper, we present a new physiological model that decomposes this total OCR into a canal and a utricular contribution, modelled by a second-order transfer function and a combination of 2 sine functions, respectively. This model yields parameters such as canal gain, cupular and adaptation time constants and a velocity storage component for the canals. Utricular gain, bias, phase and the asymmetry between the left and the right utricle are characteristic parameters generated by the model for the utricles. The model is presented along with the results of 10 healthy subjects and 2 patients with a unilateral vestibular loss due to acoustic neuroma surgery to illustrate the effectiveness of the model.

  8. Diagnostic performance of Contrast-enhanced CT in Pyrrolizidine Alkaloids-induced Hepatic Sinusoidal Obstructive Syndrome

    Science.gov (United States)

    Kan, Xuefeng; Ye, Jin; Rong, Xinxin; Lu, Zhiwen; Li, Xin; Wang, Yong; Yang, Ling; Xu, Keshu; Song, Yuhu; Hou, Xiaohua

    2016-01-01

    Hepatic sinusoidal obstruction syndrome (HSOS) can be caused by pyrrolizidine alkaloids(PAs)-containing herbals. Since PAs exposure is obscure and clinical presentation of HSOS is unspecific, it is challenge to establish the diagnosis of PAs-induced HSOS. Gynura segetum is one of the most wide-use herbals containing PAs. The aim of our study is to describe the features of contrast-enhanced computed tomography (CT) in gynura segetum-induced HSOS, and then determine diagnostic performance of radiological signs. We retrospectively analyzed medical records and CT images of HSOS patients (71 cases) and the controls (222 cases) enrolled from January 1, 2008, to Oct 31, 2015. The common findings of contrast CT in PAs-induced HSOS included: ascites (100%), hepatomegaly (78.87%), gallbladder wall thickening (86.96%), pleural effusion (70.42%), hepatic vein narrowing (87.32%), patchy liver enhancement (92.96%), and heterogeneous hypoattenuation (100%); of these signs, patchy enhancement and heterogeneous hypoattenuation were valuable features. Then, the result of diagnostic performance demonstrated that contrast CT possessed better performance in diagnosing PAs-induced HSOS compared with various parameters of Seattle criteria. In conclusion, the patients with PAs-induced HSOS display distinct radiologic features at CT-scan, which reveals that contrast-enhanced CT provides an effective noninvasive method for diagnosing PAs-induced HSOS. PMID:27897243

  9. Broadband frequency and angular response of a sinusoidal bull’s eye antenna

    Science.gov (United States)

    Beaskoetxea, U.; Navarro-Cía, M.; Beruete, M.

    2016-07-01

    A thorough experimental study of the frequency and beaming angle response of a metallic leaky-wave bull’s eye antenna working at 77 GHz with a sinusoidally corrugated profile is presented. The beam scanning property of these antennas as frequency is varied is experimentally demonstrated and corroborated through theoretical and numerical results. From the experimental results the dispersion diagram of the n  =  -1 and n  =  -2 space harmonics is extracted, and the operation at different frequency regimes is identified and discussed. In order to show the contribution of each half of the antenna, numerical examples of the near-field behavior are also displayed. Overall, experimental results are in good qualitative and quantitative agreement with theoretical and numerical calculations. Finally, an analysis of the beamwidth as a function of frequency is performed, showing that it can achieve values below 1.5° in a fractional bandwidth of 4% around the operation frequency, which is an interesting frequency-stable broadside radiation.

  10. Liver sinusoidal endothelial cells induce immunosuppressive IL-10-producing Th1 cells via the Notch pathway.

    Science.gov (United States)

    Neumann, Katrin; Rudolph, Christine; Neumann, Christian; Janke, Marko; Amsen, Derk; Scheffold, Alexander

    2015-07-01

    Under homeostasis, liver sinusoidal endothelial cells (LSECs) shift intrahepatic T-cell responses towards tolerance. However, the role of LSECs in the regulation of T-cell-induced liver inflammation is less clear. Here, we studied the capacity of LSECs to modulate pro-inflammatory Th1-cell differentiation in mice. Using in vitro co-culture systems and subsequent cytokine analysis, we showed that LSECs induced high amounts of the anti-inflammatory cytokine IL-10 in developing Th1 cells. These LSEC-stimulated Th1 cells had no pro-inflammatory capacity in vivo but instead actively suppressed an inflammatory Th1-cell-induced delayed-type hypersensitivity reaction. Blockage of IL-10 signaling in vivo inhibited immunosuppressive activity of LSEC-stimulated Th1 cells. We identified the Notch pathway as a mechanism how LSECs trigger IL-10 expression in Th1 cells. LSECs expressed high levels of the Delta-like and Jagged family of Notch ligands and induced expression of the Notch target genes hes-1 and deltex-1 in Th1 cells. Blockade of Notch signaling selectively inhibited IL-10 induction in Th1 cells by LSECs. Our findings suggest that LSEC-induced IL-10 expression in Th1 cells via the Notch pathway may contribute to the control of hepatic inflammatory immune responses by induction of a self-regulatory mechanism in pro-inflammatory Th1 cells.

  11. Optimization of the sinusoidal phase modulation technique in resonant fiber optic gyro

    Science.gov (United States)

    Wang, Linglan; Li, Hanzhao; Zhang, Jianjie; Ma, Huilian; Jin, Zhonghe

    2017-03-01

    The sinusoidal wave phase modulation and demodulation have been widely used in the signal processing system of the resonant fiber optic gyro (RFOG). An appropriate selection of the modulation frequency is of great importance, for the frequency value directly affects the slope of the demodulation curve at the resonance point which carries the gyro output information. A large demodulation slope is pursued in a high-performance RFOG. In this paper, an analytical expression of the demodulation slope is for the first time deduced in both transmission-type and reflection-type fiber ring resonators without any approximation. The relationship between the slope value and the modulation frequency at the resonance point is accurately calculated. The calculated best modulation frequency maximizing the demodulation slope at the resonance point is different from previous widely used optimal frequency given by the Lorentzian approximation method. More importantly, both theoretical and experimental results indicate that the achieved maximal demodulation slope from the proposed analytical expression method is double of that obtaining from the Lorentzian approximation method.

  12. Design optimization of sinusoidal glass honeycomb for flat plate solar collectors

    Science.gov (United States)

    Mcmurrin, J. C.; Buchberg, H.

    1980-01-01

    The design of honeycomb made of sinusoidally corrugated glass strips was optimized for use in water-cooled, single-glazed flat plate solar collectors with non-selective black absorbers. Cell diameter (d), cell height (L), and pitch/diameter ratio (P/d) maximizing solar collector performance and cost effectiveness for given cell wall thickness (t sub w) and optical properties of glass were determined from radiative and convective honeycomb characteristics and collector performance all calculated with experimentally validated algorithms. Relative lifetime values were estimated from present materials costs and postulated production methods for corrugated glass honeycomb cover assemblies. A honeycomb with P/d = 1.05, d = 17.4 mm, L = 146 mm and t sub w = 0.15 mm would provide near-optimal performance over the range delta T sub C greater than or equal to 0 C and less than or equal to 80 C and be superior in performance and cost effectiveness to a non-honeycomb collector with a 0.92/0.12 selective black absorber.

  13. A high current sinusoidal pulse generator for the diluter magnets of the LHC beam dump system

    CERN Document Server

    Vossenberg, Eugène B; Ducimetière, L; Schröder, G H

    2000-01-01

    CERN is constructing the Large Hadron Collider (LHC), a superconducting accelerator that will collide protons at a center of mass energy of 14 TeV. The two colliding beams will each store an energy of up to 540 MJ, which must be safely deposited within one beam revolution of 89 mu s on two external absorbers located about 700 m from the extraction points at the end of dedicated extraction tunnels. To avoid evaporation of the graphite absorber material by the very high energy density of the incident beams, the deposition area of the beams on the absorber front face will be increased. This is done by a pair of sinusoidally powered orthogonal magnet systems producing approximately an e-shape figure of about 35 mm diameter, with a minimum velocity of 10 mm/ mu s during the dumping process. The pulse generators of the horizontally and vertically deflecting diluter magnets are composed of capacitor banks, discharged by stacks of solid state closing switches. They are connected to the magnets by 28 m long low induct...

  14. Steady-state sinusoidal thermal characterization at chip level by internal infrared-laser deflection

    Energy Technology Data Exchange (ETDEWEB)

    Perpina, Xavier; Jorda, Xavier; Vellvehi, Miquel [Centre Nacional de Microelectronica (IMB-CNM-CSIC), Campus UAB, 08193 Bellaterra, Barcelona (Spain); Altet, Josep [Departament d' Enginyeria Electronica, Universitat Politecnica de Catalunya, Barcelona 08034 (Spain); Mestres, NarcIs [Institut de Ciencia dels Materials de Barcelona (ICMAB-CSIC), Campus UAB, 08193 Bellaterra, Barcelona (Spain)

    2008-08-07

    A new approach is reported for thermally characterizing microelectronic devices and integrated circuits under a steady-state sinusoidal regime by internal infrared-laser deflection (IIR-LD). It consists of extracting the amplitude and phase Bode plots of the temperature profile inside the chip (depth-resolved measurements in the frequency domain). As a consequence, not only are the IIR-LD performances significantly improved (accuracy, robustness to noise, control of boundary conditions and heat flux confinement) but also the direct temperature measurement is feasible when thin regions are inspected and thermal parameters can be easily extracted (thermal diffusivity). In order to show the efficiency of this technique, a thermal test chip (TTC) is used. The TTC is thermally excited by imposing a cosine-like voltage waveform. As a result, a vertical temperature profile inside the die is obtained depending on the heating frequency. Repeating this procedure at several frequencies, the frequency response of the chip internal temperature profile is derived. By comparing the experimental results with the model predictions, good agreement is achieved. This technique allows evaluation of the thermal behaviour at the chip level; also it could be useful for failure analysis.

  15. Electronic and thermal transport study of sinusoidally corrugated nanowires aiming to improve thermoelectric efficiency.

    Science.gov (United States)

    Park, K H; Martin, P N; Ravaioli, U

    2016-01-22

    Improvement of thermoelectric efficiency has been very challenging in the solid-state industry due to the interplay among transport coefficients which measure the efficiency. In this work, we modulate the geometry of nanowires to interrupt thermal transport with causing only a minimal impact on electronic transport properties, thereby maximizing the thermoelectric power generation. As it is essential to scrutinize comprehensively both electronic and thermal transport behaviors for nano-scale thermoelectric devices, we investigate the Seebeck coefficient, the electrical conductance, and the thermal conductivity of sinusoidally corrugated silicon nanowires and eventually look into an enhancement of the thermoelectric figure-of-merit [Formula: see text] from the modulated nanowires over typical straight nanowires. A loss in the electronic transport coefficient is calculated with the recursive Green function along with the Landauer formalism, and the thermal transport is simulated with the molecular dynamics. In contrast to a small influence on the thermopower and the electrical conductance of the geometry-modulated nanowires, a large reduction of the thermal conductivity yields an enhancement of the efficiency by 10% to 35% from the typical nanowires. We find that this approach can be easily extended to various structures and materials as we consider the geometrical modulation as a sole source of perturbation to the system.

  16. A portable intra-oral scanner based on sinusoidal pattern of fast phase-shifting

    Science.gov (United States)

    Jan, Chia-Ming; Lin, Ying-Chieh

    2016-03-01

    This paper presented our current research about the intra-oral scanner made by MIRDC. Utilizing the sinusoidal pattern for fast phase-shifting technique to deal with 3D digitalization of human dental surface profile, the development of pseudo-phase shifting digital projection can easily achieve one type of full-field scanning instead of the common technique of the laser line scanning. Based on traditional Moiré method, we adopt projecting fringes and retrieve phase reconstruction to forward phase unwrapping. The phase difference between the plane and object can be exactly calculated from the desired fringe images, and the surface profile of object was probably reconstructed by using the phase differences information directly. According to our algorithm of space mapping between projections and capturing orientation exchange of our intra-oral scanning configuration, the system we made certainly can be proved to achieve the required accuracy of +/-10μm to deal with intra-oral scanning on the basis of utilizing active triangulation method. The final purpose aimed to the scanning of object surface profile with its size about 10x10x10mm3.

  17. Numerical simulation heat transfer by natural convection in liquid metal with a sinusoidal temperature

    Directory of Open Access Journals (Sweden)

    Missoum Abdelkrim

    2016-01-01

    Full Text Available This study focuses on the numerical simulation of heat transfer by natural convection in a rectangular enclosure, filled with a liquid metal (low Prandtl number partially heated from below with a sinusoidal temperature. The value of the study lies in its involvement in the crystal growth for the manufacture of semiconductors and electronics cooling. Indeed, the occurrence of convection during crystal growth can lead to in homogeneities that lead to striations and defects that affect the quality of the crystals obtained by the Bridgman techniques or Chochrawlski. Temperature of the oscillations, due to the instabilities of the convective flow in the liquid metal, also induces non-uniform cooling in the solidification front. Convection is then studied in order to reduce it. A modelling of the problem in two dimensions was conducted using Comsol computer code that is based on the finite element method, by varying the configuration of the control parameters, namely, the Rayleigh number, the nature of fluid (Prandtl number and amplitude of temperature on heat transfer rate (Nusselt number on convective structures that appear.

  18. [Analysis of lorentzian line shape function broadened by non-sinusoidal wavelength modulation].

    Science.gov (United States)

    Sun, You-Qun; Wang, Yun-Tao; Ruan, Chi; Xu, Song-Song

    2014-03-01

    In the present work, the Fourier analysis of Lorentzian line shape broadened by non-sinusoidal wavelength modulation was investigated, in which the third order and above harmonic items were ignored. The analytical expression of n-order Fourier coefficient was brought out, where a variable K named harmonic distortion to characterize the ratio of the second harmonic to the first harmonic was introduced. Numerical simulations based on the cases of K > 0.01 and K 0.01, the effect of different depths of modulation on the odd and even order harmonic amplitude curve is significant. And the numerical simulation shows there exists an optimum value of modulation depth which could minimize the impact of the harmonic distortion, and both large K value and small K value would cause a great error. The conclusion of this work could be applied in error analysis of wavelength modulation spectroscopy system And the results are helpful to deepening understanding of WMS and would be the important reference for some kind of frequency stabilization technology in laser instrument.

  19. Time-domain Bayesian detection and estimation of noisy damped sinusoidal signals applied to NMR spectroscopy.

    Science.gov (United States)

    Rubtsov, Denis V; Griffin, Julian L

    2007-10-01

    The problem of model detection and parameter estimation for noisy signals arises in different areas of science and engineering including audio processing, seismology, electrical engineering, and NMR spectroscopy. We have adopted the Bayesian modeling framework to jointly detect and estimate signal resonances. This considers a model of the time-domain complex free induction decay (FID) signal as a sum of exponentially damped sinusoidal components. The number of model components and component parameters are considered unknown random variables to be estimated. A Reversible Jump Markov Chain Monte Carlo technique is used to draw samples from the joint posterior distribution on the subspaces of different dimensions. The proposed algorithm has been tested on synthetic data, the (1)H NMR FID of a standard of L-glutamic acid and a blood plasma sample. The detection and estimation performance is compared with Akaike information criterion (AIC), minimum description length (MDL) and the matrix pencil method. The results show the Bayesian algorithm superior in performance especially in difficult cases of detecting low-amplitude and strongly overlapping resonances in noisy signals.

  20. Sinusoidal electromagnetic fields promote bone formation and inhibit bone resorption in rat femoral tissues in vitro.

    Science.gov (United States)

    Zhou, Jian; Ma, Xiao-Ni; Gao, Yu-Hai; Yan, Juan-Li; Shi, Wen-Gui; Xian, Cory J; Chen, Ke-Ming

    2016-01-01

    Effects of sinusoidal electromagnetic fields (SEMFs) on bone metabolism have not yet been well defined. The present study investigated SEMF effects on bone formation and resorption in rat femur bone tissues in vitro. Cultured femur diaphyseal (cortical bone) and metaphyseal (trabecular bone) tissues were treated with 50 Hz 1.8 mT SEMFs 1.5 h per day for up to 12 days and treatment effects on bone formation and resorption markers and associated gene expression were examined. Treatment with SEMFs caused a significant increase in alkaline phosphatase (ALP) activity and inhibited the tartrate-resistant acid phosphatase (TRACP) activity in the femoral diaphyseal or metaphyseal tissues. SEMFs also significantly increased levels of mRNA expression of osterix (OSX), insulin-like growth factor (IGF-1) and ALP in the bone tissues. SEMF treatment decreased glucose content and increased lactic acid contents in the culture conditioned medium. In addition, treatment with SEMFs decreased mRNA expression levels of bone resorption-related genes TRACP, macrophage colony stimulating factor (M-CSF) and cathepsin K (CTSK) in the cultured bone tissues. In conclusion, the current study demonstrated that treatment with 1.8 mT SEMFs at 1.5 h per day promoted bone formation, increased metabolism and inhibited resorption in both metaphyseal and diaphyseal bone tissues in vitro.

  1. Hepatic sinusoidal obstruction syndrome caused by herbal medicine: CT and MRI features

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Hua; Lou, Hai Yan [Dept. of Radiology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou (China); Wang, Yi Xiang J. [Dept. of Radiology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou (China); Xu, Xiao Jun; Zhang, Min Ming [Dept. of Radiology, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou (China)

    2014-04-15

    To describe the CT and MRI features of hepatic sinusoidal obstruction syndrome (HSOS) caused by herbal medicine Gynura segetum. The CT and MRI features of 16 consecutive Gynura segetum induced HSOS cases (12 men, 4 women) were analyzed. Eight patients had CT; three patients had MRI, and the remaining five patients had both CT and MRI examinations. Based on their clinical presentations and outcomes, the patients were classified into three categories: mild, moderate, and severe. The severity of the disease was also evaluated radiologically based on the abnormal hepatic patchy enhancement in post-contrast CT or MRI images. Ascites, patchy liver enhancement, and main right hepatic vein narrowing or occlusion were present in all 16 cases. Hepatomegaly and gallbladder wall thickening were present in 14 cases (87.5%, 14/16). Periportal high intensity on T2-weighted images was present in 6 cases (75%, 6/8). Normal liver parenchymal enhancement surrounding the main hepatic vein forming a clover-like sign was observed in 4 cases (25%, 4/16). The extent of patchy liver enhancement was statistically associated with clinical severity classification (kappa = 0.565). Ascites, patchy liver enhancement, and the main hepatic veins narrowing were the most frequent signs of herbal medicine induced HSOS. The grade of abnormal patchy liver enhancement was associated with the clinical severity.

  2. Prophylactic sesame oil attenuates sinusoidal obstruction syndrome by inhibiting matrix metalloproteinase-9 and oxidative stress.

    Science.gov (United States)

    Periasamy, Srinivasan; Yang, Shan-Shan; Chen, Shin-Yi; Chang, Chih-Ching; Liu, Ming-Yie

    2013-07-01

    Sinusoidal obstruction syndrome (SOS) occurs in patients undergoing hematopoietic cell transplantation and chemotherapy. The chemotherapeutic drugs oxaliplatin and cyclophosphamide cause SOS. Sesame oil is a nutrient-rich antioxidant popular in alternative medicine. It contains sesamin, sesamol, and sesamolin, all of which contribute to its antioxidant property. The authors investigated the protective effect of prophylactic sesame oil against monocrotaline-induced SOS in rats. Male Sprague-Dawley rats were gavaged with a single dose of sesame oil (0.5, 1, 2, or 4 mL/kg). One hour later, those rats were gavaged with monocrotaline (90 mg/kg) to induce SOS. Control rats were treated with saline only. Aspartate transaminase, alanine transaminase, laminin, collagen, myeloperoxidase, nitrate content, lipid peroxidation, glutathione levels, matrix metalloproteinase (MMP)-9, and tissue inhibitor of matrix metalloproteinases (TIMP)-1 were assessed 48 hours after the monocrotaline gavage. All tested parameters except TIMP-1, laminin, collagen, and glutathione were higher in monocrotaline-treated rats than in saline-only-treated control rats. In sesame oil-treated rats, all tested parameters except TIMP-1, laminin, collagen, and glutathione were significantly attenuated compared with monocrotaline-only-treated rats. Sesame oil downregulated MMP-9 expression but upregulated TIMP-1 expression in monocrotaline-only-treated rats. In addition, a histological analysis of liver tissue samples showed that sesame oil showed significant protection. A single prophylactic dose of sesame oil protects against SOS by downregulating MMP-9 expression, upregulating TIMP-1 expression, and inhibiting oxidative stress.

  3. Therapeutic oral sesame oil is ineffectual against monocrotaline-induced sinusoidal obstruction syndrome in rats.

    Science.gov (United States)

    Periasamy, Srinivasan; Chien, Se-Ping; Liu, Ming-Yie

    2013-01-01

    The chemotherapeutic drug oxaliplatin causes sinusoidal obstruction syndrome (SOS), which is analogous to that of monocrotaline-induced SOS. Sesame oil is a nutrient-rich antioxidant in alternative medicine. It contains phenol, sesamin, sesamol, and sesamolin, all of which contribute to its antioxidant property. The authors investigated the therapeutic effect of oral sesame oil against monocrotaline-induced SOS in rats. Male Sprague-Dawley rats were gavaged with monocrotaline (90 mg/kg) to induce SOS. Control rats were treated with saline only at 0 and 24 hours. Sesame oil (0.5, 1, 2, or 4 mL/kg, orally) was given 24 hours after monocrotaline in rats. Blood samples were collected at 24 and 48 hours after monocrotaline was given to assess the level of aspartate aminotransferase (AST) and alanine aminotransferase (ALT). Histopathology was also assessed 48 hours after monocrotaline was given. AST and ALT were significantly higher in monocrotaline-treated rats than in control rats. Oral sesame oil did not decrease AST and ALT in monocrotaline-treated rats. In addition, liver pathology revealed that oral sesame oil had no therapeutic effect against SOS. Oral sesame oil is therapeutically ineffectual against monocrotaline-induced SOS.

  4. Spline-based high-accuracy piecewise-polynomial phase-to-sinusoid amplitude converters.

    Science.gov (United States)

    Petrinović, Davor; Brezović, Marko

    2011-04-01

    We propose a method for direct digital frequency synthesis (DDS) using a cubic spline piecewise-polynomial model for a phase-to-sinusoid amplitude converter (PSAC). This method offers maximum smoothness of the output signal. Closed-form expressions for the cubic polynomial coefficients are derived in the spectral domain and the performance analysis of the model is given in the time and frequency domains. We derive the closed-form performance bounds of such DDS using conventional metrics: rms and maximum absolute errors (MAE) and maximum spurious free dynamic range (SFDR) measured in the discrete time domain. The main advantages of the proposed PSAC are its simplicity, analytical tractability, and inherent numerical stability for high table resolutions. Detailed guidelines for a fixed-point implementation are given, based on the algebraic analysis of all quantization effects. The results are verified on 81 PSAC configurations with the output resolutions from 5 to 41 bits by using a bit-exact simulation. The VHDL implementation of a high-accuracy DDS based on the proposed PSAC with 28-bit input phase word and 32-bit output value achieves SFDR of its digital output signal between 180 and 207 dB, with a signal-to-noise ratio of 192 dB. Its implementation requires only one 18 kB block RAM and three 18-bit embedded multipliers in a typical field-programmable gate array (FPGA) device.

  5. Does the Newton's gravitational constant vary sinusoidally with time? An independent test with planetary orbital motions

    CERN Document Server

    Iorio, Lorenzo

    2016-01-01

    A sinusoidally time-varying pattern for the values of the Newton's constant of gravitation $G$ measured in Earth-based laboratories over the latest decades has been recently reported in the literature. Its amplitude and period amount to $A_G=1.619\\times 10^{-14} \\textrm{kg}^{-1} \\textrm{m}^3 \\textrm{s}^{-2}, P_G=5.899 \\textrm{yr}$, respectively. Given the fundamental role played by $G$ in the currently accepted theory of gravitation and the attempts to merge it with quantum mechanics, it is important to put to the test the hypothesis that the aforementioned harmonic variation may pertain $G$ itself in a direct and independent way. The bounds on $\\dot G/G$ existing in the literature may not be extended straightforwardly to the present case since they were inferred by considering just secular variations. Thus, we numerically integrated the ad-hoc modified equations of motion of the major bodies of the Solar System by finding that the orbits of the planets would be altered by an unacceptably larger amount in vie...

  6. Degradation of PsbO by the Deg protease HhoA Is thioredoxin dependent.

    Directory of Open Access Journals (Sweden)

    Irma N Roberts

    Full Text Available The widely distributed members of the Deg/HtrA protease family play an important role in the proteolysis of misfolded and damaged proteins. Here we show that the Deg protease rHhoA is able to degrade PsbO, the extrinsic protein of the Photosystem II (PSII oxygen-evolving complex in Synechocystis sp. PCC 6803 and in spinach. PsbO is known to be stable in its oxidized form, but after reduction by thioredoxin it became a substrate for recombinant HhoA (rHhoA. rHhoA cleaved reduced eukaryotic (specifically, spinach PsbO at defined sites and created distinct PsbO fragments that were not further degraded. As for the corresponding prokaryotic substrate (reduced PsbO of Synechocystis sp. PCC 6803, no PsbO fragments were observed. Assembly to PSII protected PsbO from degradation. For Synechocystis sp. PCC 6803, our results show that HhoA, HhoB, and HtrA are localized in the periplasma and/or at the thylakoid membrane. In agreement with the idea that PsbO could be a physiological substrate for Deg proteases, part of the cellular fraction of the three Deg proteases of Synechocystis sp. PCC 6803 (HhoA, HhoB, and HtrA was detected in the PSII-enriched membrane fraction.

  7. The air oxidation behavior of lanthanum ion implanted zirconium at 500 deg. C

    CERN Document Server

    Peng, D Q; Chen, X W; Zhou, Q G

    2003-01-01

    The beneficial effect of lanthanum ion implantation on the oxidation behavior of zirconium at 500 deg. C has been studied. Zirconium specimens were implanted by lanthanum ions using a MEVVA source at energy of 40 keV with a fluence range from 1x10 sup 1 sup 6 to 1x10 sup 1 sup 7 ions/cm sup 2 at maximum temperature of 130 deg. C, The weight gain curves were measured after being oxidized in air at 500 deg. C for 100 min, which showed that a significant improvement was achieved in the oxidation behavior of zirconium ion implanted with lanthanum compared with that of the as-received zirconium. The valence of the oxides in the scale was analyzed by X-ray photoemission spectroscopy; and then the depth distributions of the elements in the surface of the samples were obtained by Auger electron spectroscopy. Glancing angle X-ray diffraction at 0.3 deg. incident angles was employed to examine the modification of its phase transformation because of the lanthanum ion implantation in the oxide films. It was obviously fou...

  8. Exploring a possible origin of a 14 deg y-normal spin tilt at RHIC polarimeter

    Energy Technology Data Exchange (ETDEWEB)

    Meot, F. [Brookhaven National Lab. (BNL), Upton, NY (United States); Huang, H. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2015-06-15

    A possible origin of a 14 deg y-normal spin n0 tilt at the polarimeter is in snake angle defects. This possible cause is investigated by scanning the snake axis angle µ, and the spin rotation angle at the snake, φ, in the vicinity of their nominal values.

  9. A Byzantine chant collection from Sicily: a collaboration between Copenhagen and Piana degli Albanesi (Palermo)

    DEFF Research Database (Denmark)

    Sanfratello, Giuseppe

    2016-01-01

    The aim of this paper is to give an account of the collaboration between a collector of the Byzantine chant tradition of Piana degli Albanesi (Palermo) in Sicily, namely fr. Bartolomeo Di Salvo, and the editorial board of the Monumenta Musicae Byzantinae, i.e. an institution under the aegis......, Collections, Ethnomusicology, Critical edition, Monumenta Musicae Byzantinae (MMB)...

  10. Phosphorylation of DegU is essential for activation of amyE expression in Bacillus subtilis

    Indian Academy of Sciences (India)

    Monica Gupta; K Krishnamurthy Rao

    2014-12-01

    Alpha ()-amylase (amyE) is one of the major exo-enzymes secreted by Bacillus subtilis during the post-exponential phase. The DegS-DegU two-component system regulates expression of majority of post-exponentially expressed genes in B. subtilis. It has been demonstrated that varying levels of the phosphorylated form of DegU (DegU-P) control different cellular processes. Exo-protease production is observed when effective concentration of DegU-P rises in the cell, whereas swarming motility is favoured at very low amounts of DegU-P. In this study we show that like other exo-proteases, expression of amyE is positively regulated by increase in DegU-P levels in the cell. We also demonstrate that residues at the DNA-binding helix-turn-helix (HTH) motif of DegU are necessary for the amyE expression. This observation is further reinforced by demonstrating the direct interaction of DegU on amyE promoter.

  11. AromaDeg, a novel database for phylogenomics of aerobic bacterial degradation of aromatics.

    Science.gov (United States)

    Duarte, Márcia; Jauregui, Ruy; Vilchez-Vargas, Ramiro; Junca, Howard; Pieper, Dietmar H

    2014-01-01

    Understanding prokaryotic transformation of recalcitrant pollutants and the in-situ metabolic nets require the integration of massive amounts of biological data. Decades of biochemical studies together with novel next-generation sequencing data have exponentially increased information on aerobic aromatic degradation pathways. However, the majority of protein sequences in public databases have not been experimentally characterized and homology-based methods are still the most routinely used approach to assign protein function, allowing the propagation of misannotations. AromaDeg is a web-based resource targeting aerobic degradation of aromatics that comprises recently updated (September 2013) and manually curated databases constructed based on a phylogenomic approach. Grounded in phylogenetic analyses of protein sequences of key catabolic protein families and of proteins of documented function, AromaDeg allows query and data mining of novel genomic, metagenomic or metatranscriptomic data sets. Essentially, each query sequence that match a given protein family of AromaDeg is associated to a specific cluster of a given phylogenetic tree and further function annotation and/or substrate specificity may be inferred from the neighboring cluster members with experimentally validated function. This allows a detailed characterization of individual protein superfamilies as well as high-throughput functional classifications. Thus, AromaDeg addresses the deficiencies of homology-based protein function prediction, combining phylogenetic tree construction and integration of experimental data to obtain more accurate annotations of new biological data related to aerobic aromatic biodegradation pathways. We pursue in future the expansion of AromaDeg to other enzyme families involved in aromatic degradation and its regular update. Database URL: http://aromadeg.siona.helmholtz-hzi.de

  12. Hi-GAL, the Herschel infrared Galactic Plane Survey: photometric maps and compact source catalogues. First data release for Inner Milky Way: +68{\\deg}> l > -70{\\deg}

    CERN Document Server

    Molinari, S; Elia, D; Pestalozzi, M; Traficante, A; Pezzuto, S; Swinyard, B M; Noriega-Crespo, A; Bally, J; Moore, T J T; Plume, R; Zavagno, A; di Giorgio, A M; Liu, S J; Pilbratt, G L; Mottram, J C; Russeil, D; Piazzo, L; Veneziani, M; Benedettini, M; Calzoletti, L; Faustini, F; Natoli, P; Piacentini, F; Merello, M; Palmese, A; Del Grande, R; Polychroni, D; Rygl, K L J; Polenta, G; Barlow, M J; Bernard, J -P; Martin, P G; Testi, L; Ali, B; Andrè, P; Beltrán, M T; Billot, N; Brunt, C; Carey, S; Cesaroni, R; Compiègne, M; Eden, D; Fukui, Y; Garcia-Lario, P; Hoare, M G; Huang, M; Joncas, G; Lim, T L; Lord, S D; Martinavarro-Armengol, S; Motte, F; Paladini, R; Paradis, D; Peretto, N; Robitaille, T; Schilke, P; Schneider, N; Schulz, B; Sibthorpe, B; Strafella, F; Thompson, M A; Umana, G; Ward-Thompson, D; Wyrowski, F

    2016-01-01

    (Abridged) We present the first public release of high-quality data products (DR1) from Hi-GAL, the {\\em Herschel} infrared Galactic Plane Survey. Hi-GAL is the keystone of a suite of continuum Galactic Plane surveys from the near-IR to the radio, and covers five wavebands at 70, 160, 250, 350 and 500 micron, encompassing the peak of the spectral energy distribution of cold dust for 8 l > -70{\\deg} in a |b|<1{\\deg} latitude strip. Photometric maps have been produced with the ROMAGAL pipeline, that optimally capitalizes on the excellent sensitivity and stability of the bolometer arrays of the {\\em Herschel} PACS and SPIRE photometric cameras, to deliver images of exquisite quality and dynamical range, absolutely calibrated with {\\em Planck} and {\\em IRAS}, and recovering extended emission at all wavelengths and all spatial scales. The compact source catalogues have been generated with the CuTEx algorithm, specifically developed to optimize source detection and extraction in the extreme conditions of intens...

  13. Generation of equivalent forms of operational trans-conductance amplifier-RC sinusoidal oscillators: the nullor approach

    OpenAIRE

    Raj Senani; Manish Gupta; Data Ram Bhaskar; Abdhesh Kumar Singh

    2014-01-01

    It has been shown in two earlier papers published from this study that corresponding to a given single-operational trans-conductance amplifier (single-OTA)-RC and dual-OTA-RC sinusoidal oscillators, there are three other structurally distinct equivalent forms having the same characteristic equation, one of which employs both grounded capacitors (GC). In this study, an earlier nullor-based theory of generating equivalent op-amp oscillator circuits, proposed by the first author, is extended to ...

  14. Sinusoidal oscillators with lower gain requirements at higher frequencies based on an explicit tanh(x) nonlinearity

    KAUST Repository

    Elwakil, Ahmed S.

    2009-04-28

    Two novel sinusoidal oscillator structures with an explicit tanh(x) nonlinearity are proposed. The oscillators have the attractive feature: the higher the operating frequency, the lower the necessary gain required to start oscillations. A nonlinear model for the two oscillators is derived and verified numerically. Spice simulations using AMS BiCMOS 0.35 μ model parameters and experimental results are shown. Copyright © 2009 John Wiley & Sons, Ltd.

  15. Multivariable Adaptive Harmonic Steady-State Control for Rejection of Sinusoidal Disturbances Acting on an Unknown System

    OpenAIRE

    Kamaldar, Mohammadreza; Hoagg, Jesse B.

    2016-01-01

    This paper presents an adaptive harmonic steady-state (AHSS) controller, which addresses the problem of rejecting sinusoids with known frequencies that act on a completely unknown multi-input multi-output linear time-invariant system. We analyze the stability and closed-loop performance of AHSS for single-input single-output systems. In this case, we show that AHSS asymptotically rejects disturbances.

  16. Tusanqi-Related Sinusoidal Obstruction Syndrome in China: A Systematic Review of the Literatures.

    Science.gov (United States)

    Wang, Xiaoxi; Qi, Xingshun; Guo, Xiaozhong

    2015-06-01

    In West, sinusoidal obstruction syndrome (SOS) is often complicated with hemopoietic stem cell transplantation. By comparison, in China, SOS is frequently caused by Tusanqi-containing pyrrolizidine alkaloids. A systematic review aimed to evaluate the clinical profiles, diagnostic workup, treatment, and outcomes of Tusanqi-related SOS in China. All relevant articles were searched via PubMed, China Knowledge Resource Integrated, VIP, and Wanfang databases. Case reports were defined, as the data were available in every individual patient. Otherwise, case series were defined. Overall, 106 articles were eligible. Fifty-six case reports included 84 individual patients with SOS secondary to Tusanqi alone. All of them presented with ascites, but only 1 patient presented with upper gastrointestinal bleeding. The 1-, 3-, and 6-month cumulative survival rate was 98%, 87%, and 76%, respectively. Increased bilirubin and aspartate transaminase levels were significantly associated with poor outcome. Thirty-one case series included 402 patients with SOS secondary to Tusanqi alone. Ascites was observed in 94% of patients, but upper gastrointestinal bleeding was observed in 40% of patients. Recovery, stabilization, progression, and death were observed in 41%, 30%, 14%, and 16% of patients, respectively. Nineteen case series included 281 patients with SOS secondary to mixed etiologies. The pooled proportion of Tusanqi-related SOS was 66% (95% confidence interval: 56%-75%). Tusanqi is a major cause of SOS in China. Ascites is the most common clinical presentation of Tusanqi-related SOS. Despite a relatively good short-term outcome, further studies should be necessary to explore the long-term outcome and refine the treatment strategy.

  17. Defibrotide for the management of sinusoidal obstruction syndrome in patients who undergo haemopoietic stem cell transplantation.

    Science.gov (United States)

    Coutsouvelis, John; Avery, Sharon; Dooley, Michael; Kirkpatrick, Carl; Spencer, Andrew

    2016-11-01

    Sinusoidal obstruction syndrome, previously known as veno-occlusive disease (VOD/SOS), is a complication in patients undergoing haemopoietic stem cell transplantation (HSCT). Severe VOD/SOS, including progression to multi-organ failure, has resulted in a mortality of greater than 80%. Defibrotide's varying pharmacological actions, particularly on endothelial cells, make it is a useful agent to consider for prophylaxis and treatment of VOD/SOS. Barriers to its routine use include the high acquisition cost and the fact that neither the oral or parenteral formulations are licensed products in many countries at this time. This review summarises available literature on the use of defibrotide in the management of VOD/SOS. Publications consist predominantly of single centre cohort studies and case series. Available evidence indicates that defibrotide is effective in the management of VOD/SOS. Using defibrotide prophylaxis should also be considered, especially in the paediatric setting, where there are available results from a large, open label, randomized controlled trial. Patient outcome data from the larger studies and compassionate programs can inform consensus recommendations on dosing regimen and criteria for the treatment of VOD/SOS with defibrotide in the adult population. The reviewed literature indicates an effective and safe dose for treatment is 25mg/kg/day, continued for at least 14days or until complete response is achieved. Further studies are required to determine the optimal dose and duration of treatment in both paediatric patients and adults. Recent recommendations and a phase 3 trial using historical controls indicate that defibrotide should be included as a pharmacotherapy option in protocols guiding management of VOD/SOS.

  18. Numerical Investigation of Turbulent Natural Convection for a Cavity Having Sinusoidal Protuberances on a Vertical Wall

    Directory of Open Access Journals (Sweden)

    K Rahmani

    2013-01-01

    Full Text Available This work concerns the study of heat transfer by means of natural convection with fluids circulating in enclosures. These topics are largely studied both experimentally and numerically due to their wide industrial application in various fields such as nuclear energy, the heating and cooling of buildings, solar collectors, etc. A great deal of relevant research work consists in numerical simulations of natural convection mechanisms with laminar flows in closed cavities. In this context, the present study comes as a contribution in numerical form investigating the turbulent natural convection in vertical enclosure which presents sinusoidal protuberances on one of its vertical walls. Both the top and bottom of the enclosure are open to allow the fluid flow. The horizontal walls are supposed adiabatic. We are interested in determining for various amplitudes and periods. The influence of geometry on several factors such as: temperature, the number of local Nusselt, the turbulent kinetic energy k and its dissipation. Based on the Navier-Stokes equations and Boussinesq approximation, the equations were solved by the CFD technique using the Finite Volume Method In the case of enclosures having the form ratio equal to 0.6 (A=0.6. Given the steady conditions of heat flow on the vertical walls and the pressures at the entry and exit of the cavity, the results show that when we gradually increase the amplitudes of the protuberance wall (say a=0.005 m, a=0.010, a=0.015, a= 0.02, and a=0.025, the maximal temperature increases with the increase of amplitude. This is due to the rise of the heat transfer surface of the modified wall. Regarding heat transfer parameters, the results show that the number of local Nusselt varies relatively with the amplitudes. This explains that the modified wall is affected locally by a pure conduction. The results obtained in this study are in agreement with recent works of several authors.

  19. Gene expression profiling provides insights into pathways of oxaliplatin-related sinusoidal obstruction syndrome in humans.

    Science.gov (United States)

    Rubbia-Brandt, Laura; Tauzin, Sébastien; Brezault, Catherine; Delucinge-Vivier, Céline; Descombes, Patrick; Dousset, Bertand; Majno, Pietro E; Mentha, Gilles; Terris, Benoit

    2011-04-01

    Sinusoidal obstruction syndrome (SOS; formerly veno-occlusive disease) is a well-established complication of hematopoietic stem cell transplantation, pyrrolizidine alkaloid intoxication, and widely used chemotherapeutic agents such as oxaliplatin. It is associated with substantial morbidity and mortality. Pathogenesis of SOS in humans is poorly understood. To explore its molecular mechanisms, we used Affymetrix U133 Plus 2.0 microarrays to investigate the gene expression profile of 11 human livers with oxaliplatin-related SOS and compared it to 12 matched controls. Hierarchical clustering analysis showed that profiles from SOS and controls formed distinct clusters. To identify functional networks and gene ontologies, data were analyzed by the Ingenuity Pathway Analysis Tool. A total of 913 genes were differentially expressed in SOS: 613 being upregulated and 300 downregulated. Reverse transcriptase-PCR results showed excellent concordance with microarray data. Pathway analysis showed major gene upregulation in six pathways in SOS compared with controls: acute phase response (notably interleukin 6), coagulation system (Serpine1, THBD, and VWF), hepatic fibrosis/hepatic stellate cell activation (COL3a1, COL3a2, PDGF-A, TIMP1, and MMP2), and oxidative stress. Angiogenic factors (VEGF-C) and hypoxic factors (HIF1A) were upregulated. The most significant increase was seen in CCL20 mRNA. In conclusion, oxaliplatin-related SOS can be readily distinguished according to morphologic characteristics but also by a molecular signature. Global gene analysis provides new insights into mechanisms underlying chemotherapy-related hepatotoxicity in humans and potential targets relating to its diagnosis, prevention, and treatment. Activation of VEGF and coagulation (vWF) pathways could partially explain at a molecular level the clinical observations that bevacizumab and aspirin have a preventive effect in SOS.

  20. Dynamical pattern formation in a low-concentration magnetorheological fluid under two orthogonal sinusoidal fields

    Energy Technology Data Exchange (ETDEWEB)

    Yépez, L.D.; Carrillo, J.L. [Instituto de Física de la Universidad Autónoma de Puebla, Ciudad Universitaria, Edif. 110 A, Puebla 72570 (Mexico); Donado, F.; Sausedo-Solorio, J.M.; Miranda-Romagnoli, P. [Instituto de Ciencias Básicas e Ingeniería Universidad Autónoma del Estado de Hidalgo, Pachuca 42090, Pachuca (Mexico)

    2016-06-15

    The dynamical pattern formation of clusters of magnetic particles in a low-concentration magnetorheological fluid, under the influence of a superposition of two perpendicular sinusoidal fields, is studied experimentally. By varying the frequency and phase shift of the perpendicular fields, this configuration enables us to experimentally analyze a wide range of field configurations, including the case of a pure rotating field and the case of an oscillating unidirectional field. The fields are applied parallel to the horizontal plane where the fluid lies or in the vertical plane. For fields applied in the horizontal plane, we observed that, when the ratio of the frequencies increases, the average cluster size exhibits a kind of periodic resonances. When the phase shift between the fields is varied, the average chain length reaches maximal values for the cases of the rotating field and the unidirectional case. We analyze and discuss these results in terms of a weighted average of the time-dependent Mason number. In the case of a rotating field on the vertical plane, we also observe that the competition between the magnetic and the viscous forces determines the average cluster size. We show that this configuration generates a series of physically meaningful self-organization of clusters and transport phenomena. - Highlights: • A weighted average of the time-dependent Mason number is proposed. • The self-propelling clusters appear when a vertical rotating magnetic field is applied. • The largest average chain lengths are reached when frequencies are multiples one another. • Rotating and unidirectional alternating fields produce the largest average chain length values.

  1. Temporal modulation transfer functions obtained using sinusoidal carriers with normally hearing and hearing-impaired listeners.

    Science.gov (United States)

    Moore, B C; Glasberg, B R

    2001-08-01

    Temporal modulation transfer functions were obtained using sinusoidal carriers for four normally hearing subjects and three subjects with mild to moderate cochlear hearing loss. Carrier frequencies were 1000, 2000 and 5000 Hz, and modulation frequencies ranged from 10 to 640 Hz in one-octave steps. The normally hearing subjects were tested using levels of 30 and 80 dB SPL. For the higher level, modulation detection thresholds varied only slightly with modulation frequency for frequencies up to 80 Hz, but decreased for high modulation frequencies. The decrease can be attributed to the detection of spectral sidebands. For the lower level, thresholds varied little with modulation frequency for all three carrier frequencies. The absence of a decrease in the threshold for large modulation frequencies can be explained by the low sensation level of the spectral sidebands. The hearing-impaired subjects were tested at 80 dB SPL, except for two cases where the absolute threshold at the carrier frequency was greater than 70 dB SPL; in these cases a level of 90 dB was used. The results were consistent with the idea that spectral sidebands were less detectable for the hearing-impaired than for the normally hearing subjects. For the two lower carrier frequencies, there were no large decreases in threshold with increasing modulation frequency, and where decreases did occur, this happened only between 320 and 640 Hz. For the 5000-Hz carrier, thresholds were roughly constant for modulation frequencies from 10 to 80 or 160 Hz, and then increased monotonically, becoming unmeasurable at 640 Hz. The results for this carrier may reflect "pure" effects of temporal resolution, without any influence from the detection of spectral sidebands. The results suggest that temporal resolution for deterministic stimuli is similar for normally hearing and hearing-impaired listeners.

  2. Improved quantitative visualization of hypervelocity flow through wavefront estimation based on shadow casting of sinusoidal gratings.

    Science.gov (United States)

    Medhi, Biswajit; Hegde, Gopalakrishna M; Gorthi, Sai Siva; Reddy, Kalidevapura Jagannath; Roy, Debasish; Vasu, Ram Mohan

    2016-08-01

    A simple noninterferometric optical probe is developed to estimate wavefront distortion suffered by a plane wave in its passage through density variations in a hypersonic flow obstructed by a test model in a typical shock tunnel. The probe has a plane light wave trans-illuminating the flow and casting a shadow of a continuous-tone sinusoidal grating. Through a geometrical optics, eikonal approximation to the distorted wavefront, a bilinear approximation to it is related to the location-dependent shift (distortion) suffered by the grating, which can be read out space-continuously from the projected grating image. The processing of the grating shadow is done through an efficient Fourier fringe analysis scheme, either with a windowed or global Fourier transform (WFT and FT). For comparison, wavefront slopes are also estimated from shadows of random-dot patterns, processed through cross correlation. The measured slopes are suitably unwrapped by using a discrete cosine transform (DCT)-based phase unwrapping procedure, and also through iterative procedures. The unwrapped phase information is used in an iterative scheme, for a full quantitative recovery of density distribution in the shock around the model, through refraction tomographic inversion. Hypersonic flow field parameters around a missile-shaped body at a free-stream Mach number of ∼8 measured using this technique are compared with the numerically estimated values. It is shown that, while processing a wavefront with small space-bandwidth product (SBP) the FT inversion gave accurate results with computational efficiency; computation-intensive WFT was needed for similar results when dealing with larger SBP wavefronts.

  3. Does Newton’s gravitational constant vary sinusoidally with time? Orbital motions say no

    Science.gov (United States)

    Iorio, Lorenzo

    2016-02-01

    A sinusoidally time-varying pattern of the values of Newton’s constant of gravitation G measured in Earth-based laboratories over the last few decades has been recently reported in the literature. We put to the test the hypothesis that the aforementioned harmonic variation may pertain to G itself in a direct and independent way. We numerically integrated the ad hoc modified equations of motion of the major bodies of the Solar System, finding that the orbits of the planets would be altered by an unacceptably larger amount in view of the present-day high accuracy astrometric measurements. In the case of Saturn, its geocentric right ascension α, declination δ and range ρ would be affected by up to {10}4-{10}5 milliarcseconds and 105 km, respectively; the present-day residuals of such observables are as little as about 4 milliarcseconds and 10-1 km, respectively. We analytically calculated the long-term orbital effects induced by the putative harmonic variation of G at hand, finding non-zero rates of change for the semimajor axis a, the eccentricity e and the argument of pericenter ω of a test particle. For the LAGEOS satellite, an orbital increase as large as 3.9 m yr-1 is predicted, in contrast with the observed decay of -0.203 ± 0.035 m yr-1. An anomalous perihelion precession as large as 14 arcseconds per century is implied for Saturn, while latest observations constrain it to the 10-4 arcseconds per century level. The rejection level provided by the Mercury’s perihelion rate is of the same order of magnitude.

  4. Environmental fatigue behaviors of wrought and cast stainless steels in 310 .deg. C Deoxygenated Water

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Pyung Yeon

    2011-02-15

    Environmental fatigue behaviors of wrought type 316LN stainless steel and cast CF8M stainless steel were investigated. LCF tests were performed at fixed strain rate of 0.04%/s with 0.4%, 0.6%, 0.8%, 1.0% strain amplitudes in 310 .deg. C deoxygenated water environment. In addition, to analyze microstructure effect on fatigue behavior, low cycle fatigue tests in air environment were performed at fixed strain rate of 0.4%/s, 0.04%/s with 0.4%, 0.8% strain amplitudes. It was shown that the low cycle fatigue life of CF8M in a 310 .deg. C deoxygenated water environment was slightly longer than that of 316LN. On the other hand, the low cycle fatigue life of CF8M in a 310 .deg. C air environment was slightly shorter than that of 316LN or was similar with that of 316LN. Through OM observation and phase image analysis, it was confirmed that the ferrite content of CF8M tested in a 310 .deg. C deoxygenated water environment was larger than that of CF8M tested in a 310 .deg. C air environment. It was shown that the ferrite phase fraction of CF8M tested in 310 .deg. C deoxygenated water environment was approximately 26∼28% and that of CF8M tested in air environment was approximately 10∼12%. The difference of ferrite content in CF8M results in superior tensile properties as higher ferrite content. Furthermore, the difference of ferrite content in CF8M might be the cause of different result of fatigue life between CF8M and 316LN depending on environment. In this study, focused on CF8M having 26∼28% ferrite content, to understand the causes of these differences in a 310 .deg. C deoxygenated water environment, fracture surface and crack morphology were observed. And material factors like microstructure, mechanical properties factors like stress behavior during fatigue life, factors by environmentally assisted cracking (EAC) like hydrogen induced cracking (HIC) and chemical compositions of both materials were analyzed. Mainly in a 310 .deg. C deoxygenated water environment, the

  5. Wind-tunnel force and flow visualization data at Mach numbers from 1.6 to 4.63 for a series of bodies of revolution at angles of attack from minus 4 deg to 60 deg

    Science.gov (United States)

    Landrum, E. J.; Babb, C. D.

    1979-01-01

    Flow visualization and force data for a series of six bodies of revolution are presented without analysis. The data were obtained in the Langley Unitary Plan wind tunnel for angles of attack from -4 deg to 60 deg. The Reynolds number used for these tests was 6,600,000 per meter.

  6. Design of Helical Capacitance Sensor for Holdup Measurement in Two-Phase Stratified Flow: A Sinusoidal Function Approach

    Directory of Open Access Journals (Sweden)

    Lam Ghai Lim

    2016-07-01

    Full Text Available A 360° twisted helical capacitance sensor was developed for holdup measurement in horizontal two-phase stratified flow. Instead of suppressing nonlinear response, the sensor was optimized in such a way that a ‘sine-like’ function was displayed on top of the linear function. This concept of design had been implemented and verified in both software and hardware. A good agreement was achieved between the finite element model of proposed design and the approximation model (pure sinusoidal function, with a maximum difference of ±1.2%. In addition, the design parameters of the sensor were analysed and investigated. It was found that the error in symmetry of the sinusoidal function could be minimized by adjusting the pitch of helix. The experiments of air-water and oil-water stratified flows were carried out and validated the sinusoidal relationship with a maximum difference of ±1.2% and ±1.3% for the range of water holdup from 0.15 to 0.85. The proposed design concept therefore may pose a promising alternative for the optimization of capacitance sensor design.

  7. Nanocapsule-delivered Sleeping Beauty mediates therapeutic Factor VIII expression in liver sinusoidal endothelial cells of hemophilia A mice.

    Science.gov (United States)

    Kren, Betsy T; Unger, Gretchen M; Sjeklocha, Lucas; Trossen, Alycia A; Korman, Vicci; Diethelm-Okita, Brenda M; Reding, Mark T; Steer, Clifford J

    2009-07-01

    Liver sinusoidal endothelial cells are a major endogenous source of Factor VIII (FVIII), lack of which causes the human congenital bleeding disorder hemophilia A. Despite extensive efforts, gene therapy using viral vectors has shown little success in clinical hemophilia trials. Here we achieved cell type-specific gene targeting using hyaluronan- and asialoorosomucoid-coated nanocapsules, generated using dispersion atomization, to direct genes to liver sinusoidal endothelial cells and hepatocytes, respectively. To highlight the therapeutic potential of this approach, we encapsulated Sleeping Beauty transposon expressing the B domain-deleted canine FVIII in cis with Sleeping Beauty transposase in hyaluronan nanocapsules and injected them intravenously into hemophilia A mice. The treated mice exhibited activated partial thromboplastin times that were comparable to those of wild-type mice at 5 and 50 weeks and substantially shorter than those of untreated controls at the same time points. Further, plasma FVIII activity in the treated hemophilia A mice was nearly identical to that in wild-type mice through 50 weeks, while untreated hemophilia A mice exhibited no detectable FVIII activity. Thus, Sleeping Beauty transposon targeted to liver sinusoidal endothelial cells provided long-term expression of FVIII, without apparent antibody formation, and improved the phenotype of hemophilia A mice.

  8. Stretchable array of metal nanodisks on a 3D sinusoidal wavy elastomeric substrate for frequency tunable plasmonics

    Science.gov (United States)

    Feng, Di; Zhang, Hui; Xu, Siyi; Tian, Limei; Song, Ningfang

    2017-03-01

    Metal nanostructures integrated with soft, elastomeric substrates provide an unusual platform with capabilities in plasmonic frequency tuning of mechanical strain. In this paper, we have prepared a tunable optical device, dense arrays of plasmonic nanodisks on a low-modulus, and high-elongation elastomeric substrate with a three-dimensional (3D) sinusoidal wavy, and their optical characteristics have been measured and analyzed in detail. Since surface plasmon is located and propagates along metal surfaces with sub-wavelength structures, and those dispersive properties are determined by the coupling strength between the individual structures, in this study, a 3D sinusoidal curve elastomeric substrate is used to mechanically control the inter-nanodisk spacing by applying straining and creating a frequency tunable plasmonic device. Here we study the optical resonance peak shifting generated by stretching this type of flexible device, and the role that 3D sinusoidal curve surface configuration plays in determining the tunable properties. Since only the hybrid dipolar mode has been observed in experiments, the coupled dipole approximation (CDA) method is employed to simulate the optical response of these devices, and the experimental and simulation results show that these devices have high tunability to shift optical resonance peaks at near-infrared wavelengths, which will provide strong potential for new soft optical sensors and wearable plasmonic sensors.

  9. Human hepatic sinusoidal endothelial cells can be distinguished by expression of phenotypic markers related to their specialised functions in vivo

    Institute of Scientific and Technical Information of China (English)

    PF Lalor; WK Lai; SM Curbishley; S Shetty; DH Adams

    2006-01-01

    The hepatic sinusoids are lined by a unique population of hepatic sinusoidal endothelial cells (HSEC), which is one of the first hepatic cell populations to come into contact with blood components. However, HSEC are not simply barrier cells that restrict the access of bloodborne compounds to the parenchyma. They are functionally specialised endothelial cells that have complex roles, including not only receptor-mediated clearance of endotoxin, bacteria and other compounds, but also the regulation of inflammation, leukocyte recruitment and host immune responses to pathogens. Thus understandlng the differentiation and function of HSEC is critical for the elucidation of liver biology and pathophysiology. This article reviews methods for isolating and studying human hepatic endothelial cell populations using in vitro models. We also discuss the expression and functions of phenotypic markers, such as the presence of fenestrations and expression of VAP-1, Stabilin-1, L-SIGN, which can be used to identify sinusoidal endothelium and to permit discrimination from vascular and lymphatic endothelial cells.

  10. Sinusoidal echo-planar imaging with parallel acquisition technique for reduced acoustic noise in auditory fMRI.

    Science.gov (United States)

    Zapp, Jascha; Schmitter, Sebastian; Schad, Lothar R

    2012-09-01

    To extend the parameter restrictions of a silent echo-planar imaging (sEPI) sequence using sinusoidal readout (RO) gradients, in particular with increased spatial resolution. The sound pressure level (SPL) of the most feasible configurations is compared to conventional EPI having trapezoidal RO gradients. We enhanced the sEPI sequence by integrating a parallel acquisition technique (PAT) on a 3 T magnetic resonance imaging (MRI) system. The SPL was measured for matrix sizes of 64 × 64 and 128 × 128 pixels, without and with PAT (R = 2). The signal-to-noise ratio (SNR) was examined for both sinusoidal and trapezoidal RO gradients. Compared to EPI PAT, the SPL could be reduced by up to 11.1 dB and 5.1 dB for matrix sizes of 64 × 64 and 128 × 128 pixels, respectively. The SNR of sinusoidal RO gradients is lower by a factor of 0.96 on average compared to trapezoidal RO gradients. The sEPI PAT sequence allows for 1) increased resolution, 2) expanded RO frequency range toward lower frequencies, which is in general beneficial for SPL, or 3) shortened TE, TR, and RO train length. At the same time, it generates lower SPL compared to conventional EPI for a wide range of RO frequencies while having the same imaging parameters. Copyright © 2012 Wiley Periodicals, Inc.

  11. Pourbaix diagrams for the system copper-chlorine at 5-100 deg C

    Energy Technology Data Exchange (ETDEWEB)

    Beverskog, B. [Studsvik Material AB, Nykoeping (Sweden); Puigdomenech, I. [Studsvik Eco and Safety AB, Nykoeping (Sweden)

    1998-04-01

    Pourbaix diagrams for the copper-chlorine system in the temperature interval 5-100 deg C have been revised. Predominance diagrams for dissolved copper containing species have also been calculated. Two different total concentrations of each dissolved element, 10{sup -4} and 10{sup -6} molal for copper and 0.2 and 1.5 molal for chlorine have been used in the calculations. Chloride is the predominating chlorine species in aqueous solutions. Presence of chloride increases the corrosion regions of copper at the expense of the immunity and passivity regions in the Pourbaix diagrams. CuCl{sub 2} {center_dot} 3Cu(OH){sub 2} is the only copper-chloride solid phase that forms at the concentrations of chlorine studied. However, its stability area decreases with increasing temperature. The ion CuCl{sub 2}{sup -} predominates at all temperatures at [Cl(aq)]{sub tot}=0.2 molal and this reduces the immunity and passivity areas. A corrosion region exists between the immunity and passivity regions at 100 deg C at [Cu(aq)]{sub tot}=10{sup -6} and [Cl(aq)]{sub tot}=0.2 molal. At the chlorine concentration of 1.5 molal the corrosion region exists in the whole temperature range investigated. The ion CuCl{sub 3}{sup 2-} predominates at 5-25 and 100 deg C, while CuCl{sub 2}{sup -} predominates at 50-80 deg C at [Cl(aq)]{sub tot=}1-5 molal. A copper concentration of 10{sup -4} molal reduces the corrosion areas due to expansion of the immunity and passivity areas. However, a corrosion region still exists between the immunity and passivity regions at all investigated temperatures at pH{sub {Tau}}<9.5 and 1.5 molal chloride concentration. According to our calculations the copper canisters in the deep nuclear waste repository should not corrode at the copper concentration of 10{sup -6} molal and the chloride concentration of 0.2 molal. However, at 80-100 deg C the equilibrium potentials postulated for the Swedish nuclear repository are dangerously close to a corrosion situation. According to

  12. Book review, Igiene e Tecnologie degli Alimenti di Origine Animale Giampaolo Colavita (a cura di

    Directory of Open Access Journals (Sweden)

    Manuel Graziani

    2008-09-01

    Full Text Available Igiene e Tecnologie degli Alimenti di Origine Animale si avvale del contributo di 33 autori, tutti soci dell’Associazione Italiana Veterinari Igienisti (AIVI, che garantiscono l’appropriata trattazione di una materia estremamente vasta e dinamica. Il manuale nasce da un’iniziativa finalizzata alla realizzazione di un testo che rifletta e possa soddisfare le esigenze didattiche degli insegnamenti di un’ampia serie di materie universitarie: Igiene e Tecnologie degli Alimenti di Origine Animale della Facoltà di Medicina Veterinaria, di Agraria, nei corsi di Scienze e Tecnologie Alimentari, di Scienze e Tecnologie delle Produzioni Animali, nel corso di laurea in Tecniche della Prevenzione nell’ambiente e nei Luoghi di Lavoro, nonché in altri corsi di studio dove si insegnano le discipline relative all’igiene e alla sicurezza degli alimenti.Sono stati trattati gran parte degli alimenti di origine animale, i prodotti a base di carne, il latte e i prodotti derivati, i prodotti della pesca freschi e trasformati, i prodotti dell’alveare, le uova e gli ovoprodotti. Di particolare interesse appare il capitolo riguardante la diagnostica analitica degli alimenti, considerato che le moderne metodologie analitiche risultano fondamentali per affrontare le tematiche legate all’igiene e alla sicurezza alimentare.Il volume ha una finalità prevalentemente didattica ma è comunque rivolto a tutti coloro che operano nel campo dell’Igiene e delle Tecnologie Alimentari. Infatti, visti gli argomenti trattati come le tossinfezioni e le intossicazioni alimentari, la conservazione, il confezionamento e l’etichettatura dei prodotti alimentari, anche i professionisti del settore possono trarre dal testo elementi utili per la loro attività. Per esempio argomenti quali l’analisi del rischio, le attività di audit ed i sistemi di accreditamento e di certificazione sono particolarmente utili per chi opera nelle Aziende Sanitarie Locali e negli Istituti

  13. Sea level variabilities in the Gulf Stream between Cape Hatteras and 50 deg W - A Geosat study

    Science.gov (United States)

    Vazquez, Jorge; Zlotnicki, Victor; Fu, Lee-Lueng

    1990-01-01

    Sea level variabilities in the Gulf Stream between Cape Hatteras and 50 deg W were examined by studying sea level residuals, relative to a 2-yr mean sea level, obtained from Geosat altimetry data for the period between November 1986 and December 1988. An array of sea-level time series was constructed for a region bounded by 30 deg N and 45 deg N in latitude and by 80 deg W and 50 deg W longitude. It is shown that the spectral characteristics of this time series varies with geographic location along the Gulf Stream path. Concurrent NOAA IR images are used to aid in the interpretation of sea level observations in terms of the variability of the stream's path, demonstrating the synergistic value of the combination of satellite-altimeter and IR data.

  14. The first winter solstice observed at the meridian line of Santa Maria degli Angeli in Rome

    CERN Document Server

    Sigismondi, Costantino

    2014-01-01

    The page written by the astronomer Francesco Bianchini (1662-1729) and containing the data of the 1701 winter solstice observed at Santa Maria degli Angeli is presented for the first time in figure 2 and widely discussed along this paper. The great meridian line in the Basilica of Santa Maria degli Angeli in Rome was built in 1701/1702 with the scope to measure the Obliquity of the Earth's orbit in the following eight centuries, upon the will of pope Clement XI. During the winter solstice of 1701 the first measurements of the obliquity have been realized by Francesco Bianchini, the astronomer who designed the meridian line, upgrading the similar instrument realized by Giandomenico Cassini in San Petronio, Bononia. In this paper the accuracy of the data observed by Francesco Bianchini is discussed and compared with up-to-date ephemerides. The modern situation of this historical instrument is also presented.

  15. Isothermal section at 1400 deg. C of the Ti-Zr-Sn system

    Energy Technology Data Exchange (ETDEWEB)

    Saltykov, V.A. [I.N. Frantsevich Institute for Problems of Materials Science, Str. Krzhyzhanovsky, 3, Kiev 03142 (Ukraine)], E-mail: ssaltykov@ipms.kiev.ua; Meleshevich, K.A.; Samelyuk, A.V.; Verbytska, O.M.; Bulanova, M.V. [I.N. Frantsevich Institute for Problems of Materials Science, Str. Krzhyzhanovsky, 3, Kiev 03142 (Ukraine)

    2008-07-14

    By the methods of X-ray diffraction, metallography and microprobe examinations the character of phase equilibria at 1400 deg. C is studied for the Ti-(Ti,Zr){sub 5}Sn{sub 3}-Zr region of the Ti-Zr-Sn system. The isothermal section at 1400 deg. C is constructed. This is similar to the solidus surface and is characterized by two 3-phase regions: <{beta}Ti,Zr> + Ti{sub 3}Sn + (Ti,Zr){sub 5}Sn{sub 3} and Ti{sub 3}Sn + Ti{sub 2}Sn + (Ti,Zr){sub 5}Sn{sub 3}. Solubility of Sn in <{beta}Ti,Zr> solid solution is between 10 and 15 at.% Sn. Solubility of zirconium in Ti{sub 3}Sn is about 12 at.%.

  16. Iron oxidation kinetics study by using infrared spectral emissivity measurements below 570deg. C

    Energy Technology Data Exchange (ETDEWEB)

    Campo, Leire del [Departamento de Fisica de la Materia Condensada, Facultad de Ciencia y Tecnologi' a, Universidad del Pai' s Vasco, Barrio Sarriena s/n, 48940 Leioa, Bizkaia (Spain); Perez-Saez, Raul B. [Departamento de Fisica de la Materia Condensada, Facultad de Ciencia y Tecnologi' a, Universidad del Pai' s Vasco, Barrio Sarriena s/n, 48940 Leioa, Bizkaia (Spain); Instituto de Sintesis y Estudio de Materiales, Universidad del Pais Vasco, Apdo. 644, 48080 Bilbao (Spain)], E-mail: raul.perez@ehu.es; Tello, Manuel J. [Departamento de Fisica de la Materia Condensada, Facultad de Ciencia y Tecnologi' a, Universidad del Pai' s Vasco, Barrio Sarriena s/n, 48940 Leioa, Bizkaia (Spain); Instituto de Sintesis y Estudio de Materiales, Universidad del Pais Vasco, Apdo. 644, 48080 Bilbao (Spain)

    2008-01-15

    The oxidation kinetics of iron below 570deg. C is investigated through the dependence of the spectral emissivity on the surface oxidation state. Using the theory of radiative effects of thin films, the oxide scale thickness is obtained as a function of time. A parabolic growth has been observed in all the cases, and applying Wagner's theory, the oxidation parabolic rate constants have been calculated at four temperatures. The temperature dependence of these results has additionally been used to obtain the activation energy of the oxidation process in iron. The parabolic rate constants and activation energy values are in good agreement with the theoretical predictions, and this suggests that the lattice diffusion mechanisms for the high temperature magnetite growth also occur until 400deg. C. The experimental results are also useful to test the applicability of emissivity measurements for in situ oxidation kinetics studies in the spectral range where the scales are optically thin.

  17. Millimeter and sub-millimeter heterodyne mixing based on 2DEG hot-electron bolometers

    Science.gov (United States)

    Wang, Kai; Bell, Matthew; Ramaswamy, Rahul; Sergeev, Andrei; Strasser, Gottfried; Mitin, Vladimir

    2010-03-01

    We investigate GHz and THz heterodyne mixer based on the electron heating effect of a two-dimensional electron gas (2DEG) by electromagnetic radiation at liquid nitrogen temperatures (77K). The devices are fabricated from AlGaAs/GaAs heterostructures with a channel width of 150 μm and lengths varying from 3-20 μm. Steady-state measurements are used to investigate electron heating in these devices and determine basic parameters, such as electron-phonon energy relaxation time and electron heat capacity. We perform mixing experiments at ˜100 GHz frequency range with two Gunn diodes as the radiation sources, and find that electron heating is the primary mixing mechanism at these frequencies. For the mixing experiments at ˜ 2 terahertz range, a quantum cascade laser (QCL) is employed as the local oscillator. To optimize our device, we also investigate electron kinetics and transport properties in the 2DEG hot-electron bolometer.

  18. A liver perfusion model for studies of selective adherence and transient halting of portal blood leukocytes in sinusoids.

    Science.gov (United States)

    Durowicz, Sergiusz; Olszewski, Waldemar L

    2003-01-15

    Portal blood leukocytes play an important, but still poorly defined, role in the immune processes of the liver. In our previous studies, we showed that certain leukocyte subsets are selectively halted in the liver. These cells marginate in sinusoids and, together with resident Kupffer and endothelial sinusoidal cells, participate in antiviral and antitumor processes. The molecular mechanisms of margination and cooperation with resident sinusoidal cells require clarification. However, in vivo harvesting of portal blood leukocytes is associated with cumbersome cannulation of portal and hepatic veins and manipulation of the liver, causing major disturbances in splanchnic blood flow and liver blood supply, totally distorting sinusoidal blood perfusion and leukocyte margination. To overcome these difficulties, we have developed an in situ normothermic rat liver perfusion model permitting quantitative observations of blood leukocyte extraction in sinusoids. First, liver was flushed through the portal vein and the effluent leukocytes, named liver-associated leukocytes (LAL1), were collected from hepatic veins. Then, the liver was perfused for 60 min with 50 ml of blood using a semiclosed perfusion system. Upon completion of perfusion, the liver portal vasculature was flushed again to retrieve the leukocytes extracted from the perfusing blood (LAL2). These cells were characterized with respect to their phenotype and cytotoxicity. The mean leukocyte count of the washout before perfusion was 1.04+/-0.2x10(6)/g of liver tissue and 0.9+/-0.1x10(6)/g after 60 min of perfusion, indicating retention by the perfused liver, the live leukocyte extracting capacity. To further evaluate the efficiency of perfusion, FITC-labelled leukocytes were added to the perfusing leukocyte-free blood. Around 95% of the postperfusion washout LALs were FITC(+). Heat-killed leukocytes did not marginate in sinusoids. Preincubation of leukocytes with substances able to lower adhesion capacity, such as

  19. PUMA-PUblication MAnagement: sistemi per la gestione delle pubblicazioni degli enti di ricerca

    OpenAIRE

    Biagioni, Stefania

    2005-01-01

    Lo scopo di questa presentazione ? quello di illustrare i) come ? stato realizzato un ciclo gestionale completo dell'informazione: dall'inserimento dei metadati e dei documenti digitali alla restituzione degli stessi all'utente finale; ii) come sono stati resi accessibili via web, a livelli diversi e secondo viste diverse l'informazione prodotta; iii) come siano stati creati servizi differenti utilizzando gli stessi oggetti. Vengono illustrati i sistemi utilizzati presso il CNR di Pisa per la...

  20. Proteomica degli exosomi urinari per la ricerca di biomarcatori nella nefropatia diabetica e nelle tubulopatie ereditarie

    OpenAIRE

    Corbetta,

    2015-01-01

    Le urine costituiscono il fluido biologico di elezione nella ricerca di biomarcatori per le patologie renali in quanto possono essere raccolte in modo semplice e non invasivo; una strategia per la semplificazione del proteoma urinario è rappresentata dall’isolamento degli exosomi urinari (UE), nanovescicole di membrana (30-100 nm) rilasciate dalle cellule epiteliali nello spazio urinario. In questo lavoro abbiamo focalizzato l’attenzione sulla nefropatia diabetica (DN), una comune complicazio...

  1. Observation of Polar Mesosphere Summer Echoes using the Northernmost MST Radar at Eureka (80 deg N)

    Science.gov (United States)

    Swarnalingam, N.; Hocking, W.; Janches, D.; Drummond, J.

    2017-01-01

    We investigate long-term Polar Mesosphere Summer Echoes (PMSEs) observations conducted by the northern most geographically located MST radar at Eureka (80 deg N, 86 deg W). While PMSEs are a well recognized summer phenomenon in the polar regions, previous calibrated studies at Resolute Bay and Eureka using 51.5 MHz and33 MHz radars respectively, showed that PMSE backscatter signal strengths are relatively weak in the polar cap sites, compared to the auroral zone sites (Swarnalingam et al., 2009b; Singer et al., 2010). Complications arise with PMSEs in which the echo strength is controlled by the electrons, which are, in turn, influenced by heavily charged ice particles as well as the variability in the D-region plasma. In recent years, PMSE experiments were conducted inside the polar cap utilizing a 51 MHz radar located at Eureka. In this paper, we investigate calibrated observations, conducted during 2009-2015. Seasonal and diurnal variations of the backscatter signal strengths are discussed and compared to previously published results from the ALOMAR radar, which is a radar of similar design located in the auroral zone at Andenes, Norway (69 deg N, 16 deg E). At Eureka, while PMSEs are present with a daily occurrence rate which is comparable to the rate observed at the auroral zone site for at least two seasons, they show a great level of inter-annual variability. The occurrence rate for the strong echoes tends to be low. Furthermore, comparison of the absolute backscatter signal strengths at these two sites clearly indicates that the PMSE backscatter signal strength at Eureka is weak. Although this difference could be caused by several factors, we investigate the intensity of the neutral air turbulence at Eureka from the measurements of the Doppler spectrum of the PMSE backscatter signals. We found that the level of the turbulence intensity at Eureka is weak relative to previously reported results from three high latitude sites.

  2. Survey of the sky at the 8. 7 and 14. 4 GHz frequencies in the 0 deg - 4 deg declination range

    Energy Technology Data Exchange (ETDEWEB)

    Amirkhanyan, V.R.; Gorshkov, A.G.; Kapustkin, A.A.; Konnikova, V.K.; Lazutkin, A.N.; Larionov, M.G.; Nikanorov, A.S.; Sidorenkov, V.N.; Ugol' kova, L.S.; Khromov, O.I. (Moskovskij Gosudarstvennyj Univ. (USSR). Gosudarstvennyj Astronomicheskij Inst. ' ' GAISh' ' )

    Using the RATAN-600 radiotelescope of the USSR Academy of Sciences (from March 1979 to January 1980) the sky is observed at the 8.7 and 14.4 GHz frequencies in the 0-4 deg declination range. Lists of 82 and 24 radiosources detected at the given frequencies are presented. Six radiosources are detected for the first time. Right ascension and declination, as well as the maximum values of radio-frequency radiation fluxes are given. The problems of measuring accuracies of fluxes and coordinates and the problem of validity of detected radiosources are discussed. On the basis of comparison of the data obtained with those in other works the systematic deviation in fluxes of sources is not more than 7%.

  3. Submillimeter wavelength survey of the galactic plane from l = -5 deg to l = +62 deg - Structure and energetics of the inner disk

    Science.gov (United States)

    Hauser, M. G.; Silverberg, R. F.; Stier, M. T.; Kelsall, T.; Gezari, D. Y.; Dwek, E.; Walser, D.; Mather, J. C.; Cheung, L. H.

    1984-01-01

    Observational results are presented from a new large-scale survey of the first quadrant of the galactic plane at wavelengths of 150, 250, and 300 microns, with a 10 x 10 arcmin beam. The emission detected in the survey arises from compact sources, most of which are identified with known peaks of 5 GHz or CO emission, or both, and from an underlying diffuse background with a typical angular width of about 0.9 deg (FWHM) which accounts for most of the emission. A total of 80 prominent discrete sources are identified and characterized, of which about half have not previously been reported at far-infrared wavelengths. The total infrared luminosity within the solar circle is about 1 to 2 x 10 to the 10th solar luminosity, and is probably emitted by dust that resides in molecular clouds.

  4. Submillimeter wavelength survey of the galactic plane from l = -5 deg to l = +62 deg: Structure and energetics of the inner disk

    Science.gov (United States)

    Hauser, M. G.; Silverberg, R. F.; Stier, M. T.; Kelsall, T.; Gezari, D. Y.; Dwek, E.; Walser, D.; Mather, J. C.; Cheung, L. H.

    1984-01-01

    Results from a large scale survey of the first quadrant of the Milky Way galactic plane at wavelengths of 150, 250, and 300 microns with a 10x10 arcmin beam are presented. The emission detected in the survey arises from compact sources, most of which are identified with known peaks of 5 GHz and/or CO emission, and from an underlying diffuse background with a typical angular width of approximately 0.9 deg (FWHM) which accounts for most of the emission. A total of 80 prominent discrete sources were identified and characterized, of which about half were not previously reported at far infrared wavelengths. The total infrared luminosity within the solar circle is approximately 1 to 2x10 to the 10th power L sub 0, and is probably emitted by dust that resides in molecular clouds.

  5. Certain investigations on the reduction of side lobe level of an uniform linear antenna array using biogeography based optimization technique with sinusoidal migration model and simplified-BBO

    Indian Academy of Sciences (India)

    T S Jeyali Laseetha; R Sukanesh

    2014-02-01

    In this paper, we propose biogeography based optimization technique, with linear and sinusoidal migration models and simplified biogeography based optimization (S-BBO), for uniformly spaced linear antenna array synthesis to maximize the reduction of side lobe level (SLL). This paper explores biogeography theory. It generalizes two migration models in BBO namely, linear migration model and sinusoidal migration model. The performance of SLL reduction in ULA is investigated. Our performance study shows that among the two, sinusoidal migration model is a promising candidate for optimization. In our work, simplified – BBO algorithmis also deployed. This determines an optimum set value for amplitude excitations of antenna array elements that generate a radiation pattern with maximum side lobe level reduction. Our detailed investigation also shows that sinusoidal migration model of BBO performs better compared to the other evolutionary algorithms discussed in this paper.

  6. Hepatic sinusoidal obstruction syndrome during maintenance therapy of childhood acute lymphoblastic leukemia is associated with continuous asparaginase therapy and mercaptopurine metabolites

    DEFF Research Database (Denmark)

    Toksvang, Linea Natalie; De Pietri, Silvia; Nielsen, Stine N.

    2017-01-01

    BACKGROUND: Hepatic sinusoidal obstruction syndrome (SOS) during treatment of childhood acute lymphoblastic leukemia (ALL) has mainly been associated with 6-thioguanine. The occurrence of several SOS cases after the introduction of extended pegylated asparaginase (PEG-asparaginase) therapy...

  7. Vortex lift augmentation by suction on a 60 deg swept Gothic wing

    Science.gov (United States)

    Taylor, A. H.; Jackson, L. R.; Huffman, J. K.

    1982-01-01

    An experimental investigation was conducted in the Langley high-speed 7- by 10-foot wind tunnel to determine the aerodynamic performance of suction applied near the wing tips above the trailing edge of a 60 deg swept Gothic wing. Moveable suction inlets were symmetrically mounted in the proximity of the trailing edge, and the amount of suction was varied to maximize wing lift. Tests were conducted at Mach 0.15, 0.30, and 0.45, and the angle of attack was varied from -4 to 50 deg. The suction augmentation increases the lift coefficient over the entire range of angle of attack. The lift improvement exceeds the unaugmented wing lift by over 20%. Moreover, the augmented lift exceeds the lift predicted by vortex lattice theory to 30 deg angle of attack. Suction augmentation is postulated to strengthen the vortex system by increasing its velocity and making it more concentrated. This causes the vortex breakdown to be delayed to a higher angle of attack

  8. submitter Technical Note: Using DEG-CPCs at upper tropospheric temperatures

    CERN Document Server

    Wimmer, D; Nieminen, T; Duplissy, J; Ehrhart, S; Almeida, J; Rondo, L; Franchin, A; Kreissl, F; Bianchi, F; Manninen, H E; Kulmala, M; Curtius, J; Petäjä, T

    2015-01-01

    Over the last few years, several condensation particle counters (CPCs) capable of measuring in the sub-3 nm size range have been developed. Here we study the performance of CPCs based on diethylene glycol (DEG) at different temperatures during Cosmics Leaving OUtdoor Droplets (CLOUD) measurements at CERN. The data shown here are the first set of verification measurements for sub-3 nm CPCs under upper tropospheric temperatures using atmospherically relevant aerosol particles. To put the results in perspective we calibrated the DEG-CPC at room temperature, resulting in a cut-off diameter of 1.4 nm. All diameters refer to mobility equivalent diameters in this paper. At upper tropospheric temperatures ranging from 246.15 K to 207.15 K, we found cut-off sizes relative to a particle size magnifier in the range of 2.5 to 2.8 nm. Due to low number concentration after size classification, the cut-off diameters have a high uncertainty (±0.3 nm) associated with them. Operating two laminar flow DEG-CPCs with different c...

  9. Sexy DEG/ENaC channels involved in gustatory detection of fruit fly pheromones.

    Science.gov (United States)

    Pikielny, Claudio W

    2012-11-06

    Hydrocarbon pheromones on the cuticle of Drosophila melanogaster modulate the complex courtship behavior of males. Recently, three members of the degenerin/epithelial Na+ channel (DEG/ENaC) family of sodium channel subunits, Ppk25, Ppk23, and Ppk29 (also known as Nope), have been shown to function in gustatory perception of courtship-modulating contact pheromones. All three proteins are required for the activation of male courtship by female pheromones. Specific interactions between two of them have been demonstrated in cultured cells, suggesting that, in a subset of cells where they are coexpressed, these three subunits function within a common heterotrimeric DEG/ENaC channel. Such a DEG/ENaC channel may be gated by pheromones, either directly or indirectly, or alternatively may control the excitability of pheromone-sensing cells. In addition, these studies identify taste neurons that respond specifically to courtship-modulating pheromones and mediate their effects on male behavior. Two types of pheromone-sensing taste neurons, F and M cells, have been defined on the basis of their specific response to either female or male pheromones. These reports set the stage for the dissection of the molecular and cellular mechanisms that mediate gustatory detection of contact pheromones.

  10. EDD, a novel phosphotransferase domain common to mannose transporter EIIA, dihydroxyacetone kinase, and DegV.

    Science.gov (United States)

    Kinch, Lisa N; Cheek, Sara; Grishin, Nick V

    2005-02-01

    Using a recently developed program (SCOPmap) designed to automatically assign new protein structures to existing evolutionary-based classification schemes, we identify a evolutionarily conserved domain (EDD) common to three different folds: mannose transporter EIIA domain (EIIA-man), dihydroxyacetone kinase (Dak), and DegV. Several lines of evidence support unification of these three folds into a single superfamily: statistically significant sequence similarity detected by PSI-BLAST; "closed structural grouping" using DALI Z-scores (each protein inside a group finds all other group members with scores higher than those to proteins outside the group) that includes only these proteins sharing a unique alpha-helical hairpin at the C-terminus and excludes all other proteins with similar topology; similar domain fusions connect Dak and DegV, and genomic neighborhood organizations connect Dak and EIIA-man. Finally, both Dak and EIIA-man perform similar phosphotransfer reactions, suggesting a phosphotransferase activity for the DegV-like family of proteins, whose function other than lipid binding revealed in the crystal structure remains unknown.

  11. Vascular endothelial growth factor attenuates hepatic sinusoidal capillarization in thioacetamide-induced cirrhotic rats

    Institute of Scientific and Technical Information of China (English)

    Hao Xu; Bao-Min Shi; Xiao-Fei Lu; Feng Liang; Xing Jin; Tai-Huang Wu; Jian Xu

    2008-01-01

    AIM: To investigate the effect of vascular endothelial growth factor (VEGF) transfection on hepatic sinusoidal capillarization.MEthODS: Enhanced green fluorescent protein (EGFP)/VEGF transfection was confirmed by immunofluorescencemicroscopy and immunohistoche-mistry both in primaryhepatocytes and in normal liven Cirrhotic rats weregenerated by thioacetamide (TAA) administration andthen divided into a treatment group, which receivedinjections of 400 μg of plasmid DNA encoding an EGFP-VEGF fusion protein, and a blank group, which receivedan equal amount of normal saline through the portalvein. The portal vein pressure was measured in the normal and cirrhotic state, in treated and blank groups.The average number of fenestrae per hepatic sinusoidwas determined using transmission electron microscopy(TEM), while the relative abundance of VEGF transcriptswas examined by Gene array.RESULTS: Green fluorescent protein was observed in the cytoplasms of liver cells under immunofluorescence microscopy 24 h after transfection with EGFP/VEGFplasmid in vitro. Staining with polyclonal antibodies against VEGF illustrated that hepatocytes expressed immunodetectable VEGF both in vitro and in vitro. There were significant differences in the number of fenestrae and portal vein pressures between normal and cirrhotic rats (7.40±1.71 vs 2.30± 2.26 and 9.32± 0.85 cmH2Ovs 27.92± 0.90 cmH2O1, P < 0.02), between cirrhotic and treated rats (2.30 + 1.16 cmH2O vs 4.60± 1.65 and 17.92± 0.90 cmH2O vs 15.52±0.93 cmH20, P < 0.05)and between the treatment group and the blank group (4.60±1.65 cmH20 vs 2.10 ± 1.10 cmH20 and 25.52 +0.93 cmH20 vs 17.26 ± 1.80 cmH20, P < 0.05). Gene-array analysis revealed that the relative abundance oftranscripts of VEGF family members decreased in the cirrhotic state and increased after transfection. CONCLUSION: Injection of a plasmid encoding VEGFthrough the portal vein is an effective method toinduce the formation of fenestrae and decrease portalvein

  12. The Ni-YSZ interface - Structure, composition and electrochemical properties at 1000 deg. C

    Energy Technology Data Exchange (ETDEWEB)

    Vels Jensen, Karin

    2002-06-01

    The anode/electrolyte interface in solid oxide fuel cells (SOFC) is known to cause electrical losses. Geometrically simple Ni/Yttria-stabilised zirconia (YSZ) interfaces were examined to gain information on the structural and chemical changes occurring during experiments at 1000 deg. C in an atmosphere of 97% H2/3% H{sub 2}O. Electrochemical impedance spectroscopy at open circuit voltage (OCV) and at anodic and cathodic polarisation (100 mV) was performed. A correlation of the electrical data with the structure development and the chemical composition was attempted. Nickel wires with different impurity content (99.8% Ni and 99.995% Ni) were used to examine the impact of impurities on the polarisation resistance and contact area morphology. The electro polished nickel wires were pressed against a polished 8 mol% YSZ surface. Extensive structural changes from a flat interface to a hill and valley structure were found to occur in the contact area with the impure nickel wire, and a ridge of impurities was built along the rim of the contact area. Impurity particles in the interfacial region were also observed. The impurity phase was described as an alkali silicate glassy phase. No differences were found between polarised and non-polarised samples. With pure nickel wires, however, the microstructures depended on the polarisation/non-polarisation conditions. At non-polarised conditions a hill and valley type structure was found. Anodic polarisation produced an up to 1 {mu}m thick interface layer consisting of nano-sized YSZ particles with some Ni present. At cathodic polarisation both a granulated structure and a hill and valley structure resembling the structure of non-polarised samples were found. Small impurity ridges were surrounding the contact areas on non-polarised and cathodically polarised samples. TOF-SIMS and XPS analyses showed the presence of impurities in both the impure and pure contact areas. The impedance spectroscopy revealed that depending on the

  13. Estimation errors of the parameters of the induction machine. Comparison of models in sinusoidal regime; Erreurs d'estimation des parametres de la machine asynchrone. Comparaison de modeles en regime sinusoidal

    Energy Technology Data Exchange (ETDEWEB)

    Laroche, E. [Centre National de la Recherche Scientifique (CNRS UMR), Lab. des Sciences de l' Image, de l' Informatique et de la Teledetection, 67 - Illkirch (France); Durieu, C.; Louis, J.P. [Centre National de la Recherche Scientifique (CNRS UPRESA 8029), Lab. d' Electricite, Signaux et Robotique, 94 - Cachan (France)

    2002-07-01

    Many parametric models of induction machines in sinusoidal mode, some of which account for saturation and iron losses, are available. These models must not only be identifiable, they must also provide for an accurate estimation of physical parameters. In this paper, parameter estimation errors due to measurement noise and model errors are analyzed. The most perturbed cases, such as those neglecting saturation or iron losses, are given special consideration herein. This study allows drawing conclusions as to the practical identifiability of the various models. Results are then used to design optimal experiments in which parameter estimation errors have been minimized. (authors)

  14. Analytical and computational investigations of airfoils undergoing high-frequency sinusoidal pitch and plunge motions at low Reynolds numbers

    Science.gov (United States)

    McGowan, Gregory Z.

    Current interests in Micro Air Vehicle (MAV) technologies call for the development of aerodynamic-design tools that will aid in the design of more efficient platforms that will also have adequate stability and control for flight in gusty environments. Influenced largely by nature MAVs tend to be very small, have low flight speeds, and utilize flapping motions for propulsion. For these reasons the focus is, specifically, on high-frequency motions at low Reynolds numbers. Toward the goal of developing design tools, it is of interest to explore the use of elementary flow solutions for simple motions such as pitch and plunge oscillations to predict aerodynamic performance for more complex motions. In the early part of this research, a validation effort was undertaken. Computations from the current effort were compared with experiments conducted in a parallel, collaborative effort at the Air Force Research Laboratory (AFRL). A set of pure-pitch and pure-plunge sinusoidal oscillations of the SD7003 airfoil were examined. Phase-averaged measurements using particle image velocimetry in a water tunnel were compared with computations using two flow solvers: (i) an incompressible Navier-Stokes Immersed Boundary Method and (ii) an unsteady compressible Reynolds-Averaged Navier-Stokes (RANS) solver. The motions were at a reduced frequency of k = 3.93, and pitch-angle amplitudes were chosen such that a kinematic equivalence in amplitudes of effective angle of attack (from plunge) was obtained. Plunge cases showed good qualitative agreement between computation and experiment, but in the pitch cases, the wake vorticity in the experiment was substantially different from that predicted by both computations. Further, equivalence between the pure-pitch and pure-plunge motions was not attained through matching effective angle of attack. With the failure of pitch/plunge equivalence using equivalent amplitudes of effective angle of attack, the effort shifted to include pitch-rate and

  15. Inactivation of the Deg protease family in the cyanobacterium Synechocystis sp. PCC 6803 has impact on the outer cell layers.

    Science.gov (United States)

    Cheregi, Otilia; Miranda, Hélder; Gröbner, Gerhard; Funk, Christiane

    2015-11-01

    The serine type Deg/HtrA proteases are distributed in a wide range of organisms from Escherichia coli to humans. The cyanobacterium Synechocystis sp. PCC 6803 possesses three Deg protease orthologues: HtrA, HhoA and HhoB. Previously we compared Synechocystis 6803 wild type cells exposed to mild or severe stress conditions with a mutant lacking all three Deg proteases and demonstrated that stress had strong impact on the proteomes and metabolomes. To identify the biochemical processes, which this protease family is involved in, here we compared Synechocystis sp. PCC 6803 wild type cells with a mutant lacking all three Deg proteases grown under normal growth conditions (30°C and 40 μmol photons m(-2) s(-1)). Deletion of the Deg proteases lead to the down-regulation of proteins related to the biosynthesis of outer cell layers (e.g. the GDP mannose 4,6-dehydratase) and affected protein secretion. During the late growth phase of the culture Deg proteases were found to be secreted to the extracellular medium of the Synechocystis sp. PCC 6803 wild type strain. While cyanobacterial Deg proteases seem to act mainly in the periplasmic space, deletion of the three proteases influences the proteome and metabolome of the whole cell. Impairments in the outer cell layers of the triple mutant might explain the higher sensitivity toward light and oxidative stress, which was observed earlier by Barker and coworkers. Copyright © 2015 Elsevier B.V. All rights reserved.

  16. Realisation and advanced engineering of true optical rugate filters based on nanoporous anodic alumina by sinusoidal pulse anodisation

    Science.gov (United States)

    Santos, Abel; Yoo, Jeong Ha; Rohatgi, Charu Vashisth; Kumeria, Tushar; Wang, Ye; Losic, Dusan

    2016-01-01

    This study is the first realisation of true optical rugate filters (RFs) based on nanoporous anodic alumina (NAA) by sinusoidal waves. An innovative and rationally designed sinusoidal pulse anodisation (SPA) approach in galvanostatic mode is used with the aim of engineering the effective medium of NAA in a sinusoidal fashion. A precise control over the different anodisation parameters (i.e. anodisation period, anodisation amplitude, anodisation offset, number of pulses, anodisation temperature and pore widening time) makes it possible to engineer the characteristic reflection peaks and interferometric colours of NAA-RFs, which can be finely tuned across the UV-visible-NIR spectrum. The effect of the aforementioned anodisation parameters on the photonic properties of NAA-RFs (i.e. characteristic reflection peaks and interferometric colours) is systematically assessed in order to establish for the first time a comprehensive rationale towards NAA-RFs with fully controllable photonic properties. The experimental results are correlated with a theoretical model (Looyenga-Landau-Lifshitz - LLL), demonstrating that the effective medium of these photonic nanostructures can be precisely described by the effective medium approximation. NAA-RFs are also demonstrated as chemically selective photonic platforms combined with reflectometric interference spectroscopy (RIfS). The resulting optical sensing system is used to assess the reversible binding affinity between a model drug (i.e. indomethacin) and human serum albumin (HSA) in real-time. Our results demonstrate that this system can be used to determine the overall pharmacokinetic profile of drugs, which is a critical aspect to be considered for the implementation of efficient medical therapies.This study is the first realisation of true optical rugate filters (RFs) based on nanoporous anodic alumina (NAA) by sinusoidal waves. An innovative and rationally designed sinusoidal pulse anodisation (SPA) approach in galvanostatic

  17. Realisation and advanced engineering of true optical rugate filters based on nanoporous anodic alumina by sinusoidal pulse anodisation.

    Science.gov (United States)

    Santos, Abel; Yoo, Jeong Ha; Rohatgi, Charu Vashisth; Kumeria, Tushar; Wang, Ye; Losic, Dusan

    2016-01-21

    This study is the first realisation of true optical rugate filters (RFs) based on nanoporous anodic alumina (NAA) by sinusoidal waves. An innovative and rationally designed sinusoidal pulse anodisation (SPA) approach in galvanostatic mode is used with the aim of engineering the effective medium of NAA in a sinusoidal fashion. A precise control over the different anodisation parameters (i.e. anodisation period, anodisation amplitude, anodisation offset, number of pulses, anodisation temperature and pore widening time) makes it possible to engineer the characteristic reflection peaks and interferometric colours of NAA-RFs, which can be finely tuned across the UV-visible-NIR spectrum. The effect of the aforementioned anodisation parameters on the photonic properties of NAA-RFs (i.e. characteristic reflection peaks and interferometric colours) is systematically assessed in order to establish for the first time a comprehensive rationale towards NAA-RFs with fully controllable photonic properties. The experimental results are correlated with a theoretical model (Looyenga-Landau-Lifshitz - LLL), demonstrating that the effective medium of these photonic nanostructures can be precisely described by the effective medium approximation. NAA-RFs are also demonstrated as chemically selective photonic platforms combined with reflectometric interference spectroscopy (RIfS). The resulting optical sensing system is used to assess the reversible binding affinity between a model drug (i.e. indomethacin) and human serum albumin (HSA) in real-time. Our results demonstrate that this system can be used to determine the overall pharmacokinetic profile of drugs, which is a critical aspect to be considered for the implementation of efficient medical therapies.

  18. Ultradian rhythmicity of tyrosine aminotransferase activity in Euglena gracillis: Analysis by cosine and non-sinusoidal fitting procedures

    Science.gov (United States)

    Neuhaus-Steinmetz, Ulrich; Balzer, Ivonne; Hardeland, Rüdiger

    1990-03-01

    Although the geophysical periodicity of the earth's rotation corresponds to a biological cyclicity of ca. 24 h, cellular temporal organization comprises a multifrequency time structure, in which ultradian rhythms may be regarded as subelements of the circadian oscillator. In Euglena gracilis kept under conditons in which various cellular functions oscillate with a circadian period, tyrosine aminotransferase activity exhibited predominantly an ultradian cycle, whereas its circadian frequency was only weakly expressed. Ultradian period lengths were in the range of 4 5 h, as demonstrated by least squares fitting of cosines and of a non-sinusoidal regression function.

  19. Effect of linear sorption on solute transport in a coupled fracture-matrix system with sinusoidal fracture geometry

    Directory of Open Access Journals (Sweden)

    N.Natarajan

    2010-10-01

    Full Text Available Modeling of solute transport through fractured rock is an important component of in many disciplines especially groundwater contamination and nuclear waste disposal. Several studies have been conducted on single rock fracture using parallel plate model and recently solute and thermal transport has been numerically modeled in the sinusoidal fracture matrix coupled system. The effect of linear sorption has been studied on the same. Results suggest the high matrix porosity and matrix diffusion coefficient enhance the sorption process and reduce the matrix diffusion of solutes. The velocity of the fluid reduces with increment in fracture aperture.

  20. One dimension spring supported ball on top of a sinusoidal vibrating plate: A forced oscillation simulation using molecular dynamics method

    CERN Document Server

    Viridi, Sparisoma; Hidayat, Wahyu; Singarimbun, Alamta; Balkis, Sitti

    2011-01-01

    A ball supported by a spring is set on top of a plate which is sinusoidal vibrated. The motion is limited to one dimension motion. It is assumed that the spring is an ideal one with zero mass. The vibrating plate is considered much heavier than the ball, so that the ball motion has no influence on the plate motion. Plate vibration frequency is varied around the frequency of ball-spring system. Resonance phenomenon is reported, which needs a phase match condition to occur.

  1. A feedback control system for real-time formant estimation. I--Static and dynamic analysis for sinusoidal input signals.

    Science.gov (United States)

    Zierhofer, C M; Hochmair, E S

    1993-09-01

    This paper presents a novel analog scheme suitable for the real-time estimation of formant frequencies. Formant tracking is based on a feedback technique which uses both the amplitude and phase characteristics of two stagger-tuned bandpass filters to give an improved dynamic behavior. The implementation of the system requires a small number of components, and is practical for low-power applications. An analysis of the static and dynamic behavior is given for sinusoidal input signals. The transient response is independent of the amplitude level of the input signal. The system is designed for second formant detection in a cochlear prosthesis system.

  2. Monocular and binocular steady-state flicker VEPs: frequency-response functions to sinusoidal and square-wave luminance modulation.

    Science.gov (United States)

    Nicol, David S; Hamilton, Ruth; Shahani, Uma; McCulloch, Daphne L

    2011-02-01

    Steady-state VEPs to full-field flicker (FFF) using sinusoidally modulated light were compared with those elicited by square-wave modulated light across a wide range of stimulus frequencies with monocular and binocular FFF stimulation. Binocular and monocular VEPs were elicited in 12 adult volunteers to FFF with two modes of temporal modulation: sinusoidal or square-wave (abrupt onset and offset, 50% duty cycle) at ten temporal frequencies ranging from 2.83 to 58.8 Hz. All stimuli had a mean luminance of 100 cd/m(2) with an 80% modulation depth (20-180 cd/m(2)). Response magnitudes at the stimulus frequency (F1) and at the double and triple harmonics (F2 and F3) were compared. For both sinusoidal and square-wave flicker, the FFF-VEP magnitudes at F1 were maximal for 7.52 Hz flicker. F2 was maximal for 5.29 Hz flicker, and F3 magnitudes are largest for flicker stimulation from 3.75 to 7.52 Hz. Square-wave flicker produced significantly larger F1 and F2 magnitudes for slow flicker rates (up to 5.29 Hz for F1; at 2.83 and 3.75 Hz for F2). The F3 magnitudes were larger overall for square-wave flicker. Binocular FFF-VEP magnitudes are larger than those of monocular FFF-VEPs, and the amount of this binocular enhancement is not dependant on the mode of flicker stimulation (mean binocular: monocular ratio 1.41, 95% CI: 1.2-1.6). Binocular enhancement of F1 for 21.3 Hz flicker was increased to a factor of 2.5 (95% CI: 1.8-3.5). In the healthy adult visual system, FFF-VEP magnitudes can be characterized by the frequency-response functions of F1, F2 and F3. Low-frequency roll-off in the FFF-VEP magnitudes is greater for sinusoidal flicker than for square-wave flicker for rates ≤ 5.29 Hz; magnitudes for higher-frequency flicker are similar for the two types of flicker. Binocular FFF-VEPs are larger overall than those recorded monocularly, and this binocular summation is enhanced at 21.3 Hz in the mid-frequency range.

  3. Analytical treatment for the study of an erbium-doped fiber ring laser fed by a sinusoidally modulated pump power

    Science.gov (United States)

    Sola, I. J.; Martín, J. C.; Álvarez, J. M.

    2006-02-01

    An analytical procedure is employed to account for the response of an erbium-doped fiber ring laser whose pump power is sinusoidally modulated. The approximations considered, only strictly valid for very low modulation indexes (of the order of some hundredths), reveal the origin of some relationships between resonances of the main harmonics present in the laser response. However, both experimental and numerical results show how qualitative conclusions concerning relationships between harmonics are also valid for modulation indexes much higher than the ones corresponding to the approximation validity range.

  4. Wind-tunnel investigation of the flow correction for a model-mounted angle of attack sensor at angles of attack from -10 deg to 110 deg. [Langley 12-foot low speed wind tunnel test

    Science.gov (United States)

    Moul, T. M.

    1979-01-01

    A preliminary wind tunnel investigation was undertaken to determine the flow correction for a vane angle of attack sensor over an angle of attack range from -10 deg to 110 deg. The sensor was mounted ahead of the wing on a 1/5 scale model of a general aviation airplane. It was shown that the flow correction was substantial, reaching about 15 deg at an angle of attack of 90 deg. The flow correction was found to increase as the sensor was moved closer to the wing or closer to the fuselage. The experimentally determined slope of the flow correction versus the measured angle of attack below the stall angle of attack agreed closely with the slope of flight data from a similar full scale airplane.

  5. Lampi di possibili tempeste. Arte e letteratura nel Foucault degli anni Settanta.

    Directory of Open Access Journals (Sweden)

    Diego Melegari

    2012-12-01

    Full Text Available Dopo avere rivestito un ruolo fondamentale negli scritti archeologici degli anni Sessanta, i riferimenti a pittura e letteratura sembrano scomparire dalla riflessione foucaultiana. Si tratta, in realtà, di uno slittamento dalle opere maggiori a brevi interventi in cui ad emergere è soprattutto il coinvolgimento soggettivo di Foucault. Questo passaggio, però, non è che un aspetto di una radicale riformulazione della funzione storico-ontologica precedentemente attribuita a letteratura e arte in favore di forme di esperienza non-strategica, dunque irriducibile al nesso potere-resistenza, e allo stesso tempo riattivabile come critica, anche politica, nel rapporto tra tempo storico e trasformazione della soggettività.

  6. Il problema dei futuri contingenti e la semantica relativista degli enunciati al futuro

    Directory of Open Access Journals (Sweden)

    Diana Mazzarella

    2011-11-01

    Full Text Available L'articolo si propone tre obiettivi. In primo luogo, introdurre al problema dei futuri contingenti, evidenziando i limiti di un'analisi semantica standard degli enunciati al futuro. In secondo luogo, presentare le strategie di implementazione della semantica standard finalizzate ad un approccio semantico di tipo relativistico, distinguendo tra relativismo moderato e relativismo radicale. In terzo luogo, presentare il tentativo di risoluzione del problema in questione attraverso l'adozione di una prospettiva semantica relativista, con esplicito riferimento alle riflessioni di MacFarlane.

  7. L’avventura del teatro granducale degli Uffizi (1586-1637

    Directory of Open Access Journals (Sweden)

    Anna Maria Testaverde

    2016-06-01

    Full Text Available The essay reconstructs the chronological details of the construction and disposal of the Teatro degli Uffizi. An extensive unpublished documentation, and a newly discovered plan of the theatre in the Archivio di Stato di Modena, bring to light hitherto unknown persons and situations. The study anticipates reflections and proposals for a structural solution that would modify the model proposed in 1975 by Ludovico Zorzi. As a foundation of these new hypotheses, the essay offers a re-reading of the Vitruvius’s theories on which the florentine highly specialised technical skills were based on.

  8. “Il coraggio di essere giovani”: un progetto sulla Fgci di Modena degli anni Ottanta

    Directory of Open Access Journals (Sweden)

    Claudia Capelli

    2015-12-01

    Full Text Available L’Istituto Storico di Modena promuove una ricerca sulla Fgci di Modena degli anni Ottanta con l'obiettivo di cominciare a riflettere sul decennio conclusivo della storia del Pci, un periodo di crisi profonda della cultura politica comunista che la storiografia non ha ancora affrontato in modo sistematico. Il caso modenese permette di osservare alcuni importanti elementi dell'esperienza della Fgci “rifondata”, come il nuovo approccio alla comunicazione politica e il rapporto con i movimenti sociali.

  9. Fattori di crescita e recettori tirosin chinasici nelle neoplasie e displasie degli animali domestici

    OpenAIRE

    Muscatello, Luisa Vera

    2016-01-01

    La perdita della comunicazione cellulare può portare ad una crescita deregolata e dunque alla trasformazione neoplastica. Gli scopi dello studio di dottorato sono stati di individuare il rapporto funzionale di alcuni fattori di crescita (FC) e dei loro recettori (RTC) in tipi di neoplasie e displasie degli animali domestici, quali: 1. Amplificazione del proto-oncogene ERBB2 e sovra-espressione del RTC erb-b2. in tumori mammari della gatta. 2. Espressione di erb-b2, di recettori ormonal...

  10. A catalogue of galaxies behind the southern Milky Way. - II. The Crux and Great Attractor regions (l = 289deg - 338deg)

    CERN Document Server

    Woudt, P A; Woudt, Patrick A.; Kraan-Korteweg, Renee C.

    2001-01-01

    In this second paper of the catalogue series of galaxies behind the southern Milky Way, we report on the deep optical galaxy search in the Crux region (289deg = 0.2 arcmin were identified in this ~850 square degree area: 3759 galaxies in the Crux region and 4423 galaxies in the Great Attractor region. Of the 8182 galaxies, 229 (2.8%) were catalogued before in the optical (3 in radio) and 251 galaxies have a reliable (159), or likely (92) cross-identification in the IRAS Point Source Catalogue (3.1%). A number of prominent overdensities and filaments of galaxies are identified. They are not correlated with the Galactic foreground extinction and hence indicative of extragalactic large-scale structures. Redshifts obtained at the South African Astronomical Observatory (SAAO) for 518 of the newly catalogued galaxies in the Crux and Great Attractor regions (Fairall et al. 1998; Woudt et al. 1999) confirm distinct voids and clusters in the area here surveyed. With this optical galaxy search, we have reduced the widt...

  11. MODIS/Terra 8-Day Clear Sky Radiance Bias Daily L3 Global 1Deg Zonal Bands V006

    Data.gov (United States)

    National Aeronautics and Space Administration — MODIS 8-day clear-sky radiance bias (observed - calculated) statistics are provided for 1Deg latitudinal zones and selected thermal bands. Separation by day and...

  12. MODIS/Aqua 8-Day Clear Sky Radiance Bias Daily L3 Global 1Deg Zonal Bands V006

    Data.gov (United States)

    National Aeronautics and Space Administration — MODIS 8-day clear-sky radiance bias (observed - calculated) statistics are provided for 1Deg latitudinal zones and selected thermal bands. Separation by day and...

  13. Subtle anion effects on anion exchange and thermolysis: Square supra-channels via array of sinusoidal coordination polymers

    Science.gov (United States)

    Moon, So Yun; Park, Min Woo; Noh, Tae Hwan; Jung, Ok-Sang

    2013-12-01

    Self-assembly of AgX (X=ClO4-,BF4-) with a new diethylbis(4-pyridyl)silane (L) ligand basically gives rise to a one-dimensional (1D) sinusoidal structure. Weak C-H⋯π interactions between ethyl and pyridyl groups result in the formation of infinite square supra-channel structures via a molecular array of four sinusoidal chains. The supra-channel size is 10.1-10.7 Å with a void cross-section of 2.1-3.1 Å for [Ag(L)](ClO4) and 9.9-10.5 Å with a void cross-section of 2.0-3.0 Å for [Ag(L)](BF4). The supra-channels are occupied by each counteranion. Anion exchange of [Ag(L)](BF4) with NaClO4 occurs smoothly, whereas the reverse anion exchange of [Ag(L)](ClO4) with NaBF4 does not. Calcination of [Ag(L)](ClO4) crystals at 400 °C produces a circle morphology with evolving burned organics, and, at 600 °C, forms network circles consisting of a silver(0)/silver chloride (chlorargyrite)/silicon(IV) oxide composite with a micro-sized convexo-concave surface. In contrast, calcination of [Ag(L)](BF4) crystals at 600 °C produces silver(0) materials without silicon(IV) oxide.

  14. Evolutionary Optimization of Non-Continuous and Non-Sinusoidal Gaits of a Self-Propelled Swimmer

    Science.gov (United States)

    Ayancik, Fatma; Akoz, Emre; Moored, Keith

    2016-11-01

    Animals propel themselves through the oceans with a wide variety of swimming gaits. However, it is typically assumed that biological propulsion is achieved by using continuous, sinusoidal motions. Yet, animals have been observed using non-continuous or intermittent swimming gaits and at many times non-sinusoidal motions. Through the use of an evolutionary algorithm, optimal swimming gaits that can be both nonsinusoidal and intermittent are determined. Both the non-dimensional cost of transport and swimming speed are optimized for a virtual body combined with a two-dimensional self-propelled pitching and heaving foil within a boundary element method numerical framework. Nonsinusoidal motions are varied from a triangle-wave to a square-wave motion and the intermittency of the gait is varied by changing the duty cycle of the active phase to the coasting phase during swimming. Both pure pitching, and combined heaving and pitching motions are examined. The Pareto front of optimal solutions is investigated for trends in the optimally efficient swimming gait as the swimming speed is increased. The variation in the wake structures produced by optimally efficient swimmers is probed. Supported by the Office of Naval Research under Program Director Dr. Bob Brizzolara, MURI Grant Number N00014-14-1-0533.

  15. Time-frequency analyses of fluid-solid interaction under sinusoidal translational shear deformation of the viscoelastic rat cerebrum

    Science.gov (United States)

    Leahy, Lauren N.; Haslach, Henry W.

    2017-06-01

    During normal extracellular fluid (ECF) flow in the brain glymphatic system or during pathological flow induced by trauma resulting from impacts and blast waves, ECF-solid matter interactions result from sinusoidal shear waves in the brain and cranial arterial tissue, both heterogeneous biological tissues with high fluid content. The flow in the glymphatic system is known to be forced by pulsations of the cranial arteries at about 1 Hz. The experimental shear stress response to sinusoidal translational shear deformation at 1 Hz and 25% strain amplitude and either 0% or 33% compression is compared for rat cerebrum and bovine aortic tissue. Time-frequency analyses aim to correlate the shear stress signal frequency components over time with the behavior of brain tissue constituents to identify the physical source of the shear nonlinear viscoelastic response. Discrete fast Fourier transformation analysis and the novel application to the shear stress signal of harmonic wavelet decomposition both show significant 1 Hz and 3 Hz components. The 3 Hz component in brain tissue, whose magnitude is much larger than in aortic tissue, may result from interstitial fluid induced drag forces. The harmonic wavelet decomposition locates 3 Hz harmonics whose magnitudes decrease on subsequent cycles perhaps because of bond breaking that results in easier fluid movement. Both tissues exhibit transient shear stress softening similar to the Mullins effect in rubber. The form of a new mathematical model for the drag force produced by ECF-solid matter interactions captures the third harmonic seen experimentally.

  16. Time-dependent Creep Crack Growth Behavior of Alloy 617 at 800 .deg. C

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Woogon; Kim, Minhwan; Kim, Yongwan [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Park, Jaeyoung; Ekaputra, I. M. W. [Pukyong National Univ., Busan (Korea, Republic of)

    2014-05-15

    The VHTR components are designed to be used for a 60 year lifetime at a high temperature, the creep crack growth (CCG) behavior as well as creep behavior is very important for the design application due to creep damage during the long service life at elevated temperatures. Alloy 617 is a major candidate material for the IHX component. The design of the component, which will operate well into the creep range, will require a good understanding of creep crack growth deformation. Efforts are now being undertaken in the Generation IV program to provide data needed for the design and licensing of the nuclear plants, and with this goal in mind, to meet the needs of the conceptual designers of the VHTR system, 'Gen-IV Materials Handbook DB' is being established through an international collaboration program of several GIF (Gen-IV Forum) countries. CCG experimental data should be prepared to 'the Gen-IV Materials Handbook DB' website, because the CCG data for Alloy 617 are not available in the ASME design code. In this paper, experimental creep crack growth data were obtained through a series of CCG tests performed under different applied loads at 800 .deg. C. The CCG behavior was characterized in terms of the C{sup *} fracture mechanics parameter, and the CCGR equation for Alloy 617 was presented. Experimental CCG data of Alloy 617 were obtained from a series of creep crack growth tests under different applied loads at 800 .deg. C.

  17. On th meridional surface profile of the Gulf Stream at 55 deg W

    Science.gov (United States)

    Hallock, Zachariah R.; Teague, William J.

    1995-01-01

    Nine-month records from nine inverted echo sounders (IESs) are analyzed to describe the mean baroclinic Gulf Stream at 55 deg W. IES acoustic travel times are converted to thermocline depth which is optimally interpolated. Kinematic and dynamic parameters (Gulf Stream meridional position, velocity, and vorticity) are calculated. Primary Gulf Stream variabiltiy is attributed to meandering and and changes in direction. A mean, stream-coordinate (relative to Gulf Stream instantaneous position and direction) meridional profile is derived and compared with results presented by other investigators. The mean velocity is estimated at 0.84 m/s directed 14 deg to the right eastward, and the thermocline (12 c) drops 657 m (north to south), corresponding to a baroclinic rise of the surface of 0.87 m. The effect of Gulf Stream curvature on temporal mean profiles is found to be unimportant and of minimal importance overall. The derived, downstream current profile is well represented by a Gaussian function and is about 190 km wide where it crosses zero. Surface baroclinic transport is estimated to be 8.5 x 10(exp 4) sq m/s, and maximum shear (flanking the maximum) is 1.2 x 10(exp -5). Results compare well with other in situ observational results from the same time period. On the other hand, analyses (by others) of concurrent satellite altimetry (Geosat) suggest a considerable narrower, more intense mean Gulf Stream.

  18. Selecting Eco-Friendly Thermal Systems for the “Vittoriale Degli Italiani” Historic Museum Building

    Directory of Open Access Journals (Sweden)

    Davide Astiaso Garcia

    2015-09-01

    Full Text Available Thermal systems installed in museums should guarantee the maintenance of the optimal hygrothermal parameters ranges for the conservation of their collection materials. Considering the preservation of historic buildings, according to their historical and landscaping constraints, not all the thermal system typologies could be installed in these buildings’ typologies. Therefore, the main aim of this paper is to present some indications for the choice of the best thermal system solutions for a considered historic museum building, called Vittoriale degli Italiani, in the north of Italy, taking into account their installation feasibility and their related environmental impacts. The methodology includes a monitoring of the current hygrothermal parameters as well as the assessment of design heat and cooling loads related to the maintenance of the optimal hygrothermal parameters ranges for the conservation of collection materials. In addition, a Life Cycle Assessment (LCA of each selected system typology is considered for highlighting the most eco-friendly solution among the suitable ones. The obtained results highlights the feasible thermal system solutions able to maintain the hygrothermal parameters between the optimal ranges with a lower environmental impact in the Vittoriale degli Italiani historic museum building.

  19. The segregation of starless and protostellar clumps in the Hi-GAL l=224deg region

    CERN Document Server

    Olmi, L; Elia, D; Jones, P

    2016-01-01

    Stars form in dense, dusty structures, which are embedded in larger clumps of molecular clouds often showing a clear filamentary structure on large scales (> 1pc). One of the best-studied regions in the Hi-GAL survey can be observed toward the l=224deg field. Here, a filamentary region has been studied and it has been found that protostellar clumps are mostly located along the main filament, whereas starless clumps are detected off this filament and are instead found on secondary, less prominent filaments. We want to investigate this segregation effect and how it may affect the clumps properties. We mapped the 12CO(1-0) line and its main three isotopologues toward the two most prominent filaments observed toward the l=224deg field using the Mopra radio telescope, in order to set observational constraints on the dynamics of these structures and the associated starless and protostellar clumps. Compared to the starless clumps, the protostellar clumps are more luminous, more turbulent and lie in regions where the...

  20. Corrosion of stainless steels in lead-bismuth eutectic up to 600 deg. C

    Energy Technology Data Exchange (ETDEWEB)

    Soler, L. [Dpto. Fision Nuclear, CIEMAT, Edificio 30, Avda. Complutense 22, Madrid 28040 (Spain)]. E-mail: laura.soler@ciemat.es; Martin, F.J. [Dpto. Fision Nuclear, CIEMAT, Edificio 30, Avda. Complutense 22, Madrid 28040 (Spain); Hernandez, F. [Dpto. Fision Nuclear, CIEMAT, Edificio 30, Avda. Complutense 22, Madrid 28040 (Spain); Gomez-Briceno, D. [Dpto. Fision Nuclear, CIEMAT, Edificio 30, Avda. Complutense 22, Madrid 28040 (Spain)

    2004-11-01

    An experimental program has been carried out to understand the differences in the corrosion behaviour between different stainless steels: the austenitic steels 304L and 316L, the martensitic steels F82Hmod, T91 and EM10, and the low alloy steel P22. The influence of oxygen level in Pb-Bi, temperature and exposure time is studied. At 600 deg. C, the martensitic steels and the P22 steel exhibit thick oxide scales that grow with time, following a linear law for the wet environment and a parabolic law for the dry one. The austenitic stainless steels show a better corrosion behaviour, especially AISI 304L. Under reducing conditions, the steels exhibit dissolution, more severe for the austenitic stainless steels. At 450 deg. C, all the materials show an acceptable behaviour provided a sufficient oxygen level in the Pb-Bi. At reducing conditions, the martensitic steels and the P22 steel have a good corrosion resistance, while the austenitic steels exhibit already dissolution at the longer exposures.

  1. Searching for dark matter halos in the Suprime-Cam 2 sq deg field

    CERN Document Server

    Miyazaki, S; Shimasaku, K; Furusawa, H; Doi, M; Hamabe, M; Imi, K; Kimura, M; Komiyama, Yu; Nakata, F; Okada, N; Okamura, S; Ouchi, M; Sekiguchi, M; Yagi, M; Yasuda, N

    2002-01-01

    We report the first result of weak gravitational lensing survey on a 2.1 sq deg Rc-band image taken with a wide field camera (Suprime-Cam) on the prime focus of 8.2 m Subaru Telescope. The weak lensing mass reconstruction is applied to the data to search for dark matter halos of cluster scale; M >= 10^14 solar mass. The reconstructed convergence field is divided by 1-sigma noise to obtain the signal-to-noise ratio map (S/N-map) of the detection. Local maxima and minima are searched on the S/N-map and the probability distribution function (PDF) of the peaks are created to compare with model predictions. We found excess over noise PDF created from the randomized realization on both positive and negative sides. Negative peaks imply the presence of voids in the dark matter distribution and this is the first report of the detection. Positive peaks, on the other hand, represent the dark matter halos and the number count of the halos on the 2.1 sq deg image is 4.9 +- 2.3 for S/N > 5 where the Gaussian smoothing radi...

  2. La partecipazione degli enti ecclesiastici cattolici alle società di capitali

    Directory of Open Access Journals (Sweden)

    Ludovica Decimo

    2015-01-01

    Full Text Available SOMMARIO: 1. Valutazioni preliminari e nuove prospettive d’indagine – 2. L’attività negoziale degli enti ecclesiastici: le autorizzazioni canoniche – 3. La rilevanza dei controlli canonici nell’ordinamento italiano – 4. L’omissione delle autorizzazioni canoniche nella fase costitutiva della s.p.a. e della s.r.l. – 5. I controlli canonici e la circolazione delle azioni della s.p.a. – 6. La cessione di quote di s.r.l. in assenza delle autorizzazioni canoniche – 7. L’invalidità delle delibere peggiorative della situazione patrimoniale dell’ente ecclesiastico (l’aumento reale di capitale, la fusione, la trasformazione regressiva – 8. La partecipazione dell’ente ecclesiastico socio all’assemblea societaria: brevi cenni sulla rappresentanza delle persone giuridiche canoniche – 9. Il falsus procurator dell’ente ecclesiastico socio in assemblea ordinaria – 10. Ipotesi concrete di partecipazione degli enti ecclesiastici cattolici alle società di capitali, in particolare, alle s.r.l. – 11. L’assenza delle autorizzazioni canoniche nell’atto costitutivo della società “Tabor S.r.l.” – 12. L’errata individuazione delle autorizzazioni canoniche necessarie nell’atto costitutivo della società “G.M.G. E.R. Rinnovabili S.r.l. Unipersonale”.

  3. InAs 2DEGs:What's the g-factor?

    Science.gov (United States)

    McCombe, B. D.; Pakmehr, Mehdi; Khaetskii, A.; Chiatti, Olivio; Fischer, S. F.; Buchholz, S.; Heyn, C.; Hansen, W.; Cahay, M.; Newrock, R. S.; Bandari, Nikhil

    2014-03-01

    Interest in spin-orbit effects in semiconductors has led us to study the electron g-factor in quasi-2DEG InAs samples. We have made magneto-transport and -photoresponse (PR) measurements on InAs QW structures in magnetic fields up to 10 T. THz cyclotron resonance (CR) is manifested in PR as a resonant envelope of the amplitude of quantum oscillations, which show clear spin-splitting (for lower mobility samples) down 4T, while direct R_xx measurements show no spin-splitting up to 9T. R_xx oscillations in a higher mobility sample show well-resolved spin-splittings over a range of fields as does the PR. We have simulated the data with a theoretical expression for 2DEG SdH oscillations (coupled with CR resonant carrier heating for the PR) and extracted g-factors from fits. We also used a different (commonly used) method, SdH oscillations vs. tilt angle of the field to extract g-factors from the angle at which the SdH frequency doubles. We find very large g-factors from fits to R_xx and PR (14 - 20), but g-factors 2-3 times smaller for these same samples from tilted field experiments (close to estimated band g-factors). These results are discussed in terms of exchange effects. Support: NSF DMR 1008138 (Buffalo); NSF ECCE 1028483(Cincinnati); DFG Fi932/4-1(Berlin).

  4. Formation scenarios for the young stellar associations between galactic longitudes l = 280-360 deg

    CERN Document Server

    Sartori, M J; Dias, W S; Sartori, Marilia J.; Lepine, Jacques R. D.; Dias, Wilton S.

    2003-01-01

    We investigate the spatial distribution, the space velocities and age distribution of the pre-main sequence (PMS) stars belonging to Ophiuchus, Lupus and Chamaeleon star-forming regions (SFRs), and of the young early-type star members of the Scorpius-Centaurus OB association. These young stellar associations extend over the galactic longitude range from 280 deg. to 360 deg., and are at a distance interval of around 100 and 200 pc. The study is based on a compilation of distances, proper motions and radial velocities from the literature for the kinematic properties, and of basic stellar data for the construction of Hertzsprung-Russel diagrams. Although there was no well-known OB association in Chamaeleon, the distances and the proper motions of a group of 21 B- and A-type stars, taken from the Hipparcos Catalogue, lead us to propose that they form a young association. We show that the young early-type stars of the OB associations and the PMS stars of the SFRs follow a similar spatial distribution, i.e., there ...

  5. L’evoluzione cerebrale degli ominidi: quando antropologia, paleontologia e psicologia convergono su una domanda

    Directory of Open Access Journals (Sweden)

    Christian Agrillo

    2008-06-01

    Full Text Available Lo studio dell’evoluzione cerebrale degli ominidi rappresenta uno dei punti di arrivo di diverse discipline che pongono l’essere umano al centro del proprio interesse: la paleontologia, che si serve dei reperti fossili per evincere la storia evolutiva del cranio e del cervello; l’antropologia, che utilizza utensili e tradizioni di culture differenti per accostarsi anche allo studio della cognizione umana e infine la psicologia che - attraverso il confronto con le capacità cognitive di altri primati - si propone di indagare l’unicità o meno delle potenzialità mentali di cui disponiamo, alla ricerca di elementi condivisi dai nostri parenti più prossimi evolutisi in una diversa regione del continente africano.Comprendere quali siano state le cause che hanno diversificato il cammino dell’Uomo da quello degli altri primati significa, in primo luogo, capire quali fattori costituiscano effettivamente una prerogativa della specie umana, cosa ci differenzia dalle scimmie e come questo possa essere avvenuto. Diverse teorie sono state ipotizzate al riguardo: il presente lavoro riassume le principali visioni correnti, ponendo l’una di fronte l’altra e suggerendo come la mente umana possa essersi evoluta in seguito alla compresenza di più fattori che hanno spinto verso la medesima direzione, a differenza di quanto avvenuto per le scimmie antropomorfe.

  6. Interplay of Rashba and sp-d exchange couplings in magnetic 2DEGs

    Science.gov (United States)

    Mireles, Francisco; Freire, Henrique H. P.; Egues, J. Carlos

    2006-03-01

    In diluted magnetic semiconductor (DMS) quantum wells the sp-d exchange interaction between the itinerant conduction electrons in the well and the localized electrons in the d orbitals of the Mn impurities gives rise to interesting spin-dependent physics [1]. Recently, the interplay of the Rashba spin-orbit and the sp-d exchange interactions in Mn-based wells has been recognized via Shubnikov-de-Haas measurements [2]. While the Rashba spin-orbit has been extensively studied in non-magnetic 2DEGs, its role in DMS systems with a competing sp-d exchange interaction has not yet been addressed theoretically. In this work we present a k.p derivation of an effective Hamiltonian for a Mn-based quantum well with competing Rashba and sp-d interactions, and show numerical results for the magnetoresistance ρxx of typical magnetic 2DEGs using our effective Hamiltonian model. Our results shows interesting beating patterns of the ρxx as a function of the temperature and carrier density which suggests a significant interplay between the spin-orbit and sp-d exchange interactions, as a recent experiment observes [2]. [1] J. C. Egues, PRL 78, 4578 (1998); H. J. P. Freire and J. C. Egues, cond-mat/0412491. [2] Y. S. Gui et al. EPL. 65, 393 (2004).

  7. The p-wave superconductivity in the presence of Rashba interaction in 2DEG.

    Science.gov (United States)

    Weng, Ke-Chuan; Hu, C D

    2016-07-26

    We investigate the effect of the Rashba interaction on two dimensional superconductivity. The presence of the Rashba interaction lifts the spin degeneracy and gives rise to the spectrum of two bands. There are intraband and interband pairs scattering which result in the coupled gap equations. We find that there are isotropic and anisotropic components in the gap function. The latter has the form of cos φk where . The former is suppressed because the intraband and the interband scatterings nearly cancel each other. Hence, -the system should exhibit the p-wave superconductivity. We perform a detailed study of electron-phonon interaction for 2DEG and find that, if only normal processes are considered, the effective coupling strength constant of this new superconductivity is about one-half of the s-wave case in the ordinary 2DEG because of the angular average of the additional in the anisotropic gap function. By taking into account of Umklapp processes, we find they are the major contribution in the electron-phonon coupling in superconductivity and enhance the transition temperature Tc.

  8. Driving and control strategies in alternative current machines of permanent magnet with non-sinusoidal flux; Estrategias de acionamento e controle em maquinas CA de ima permanente com fluxo nao senoidal

    Energy Technology Data Exchange (ETDEWEB)

    Monteiro, Jose Roberto Boffino de Almeida

    1997-07-01

    The aim of this work is to study and analyze the torque performance of brush less machines with non-sinusoidal distributed magnetic fluxes. The machine type considered is a surface mount permanent magnet brush less machine. Three mathematical models for the machine are considered: the per stator phase, the vectorial and the linear second order speed-voltage models. Machines with different stator windings are compared including the permanent magnet synchronous machines with sinusoidal distributed stator windings. The torque outputs of these machines are obtained considering two kinds of open loop driving systems: one with a six-pulse waveform and other with a sinusoidal waveform. Finally, a vectorial control is proposed for the non-sinusoidal machines. The torque ripple as well the overall performance of non-sinusoidal machines with vectorial control is compared to that of sinusoidal machines. (author)

  9. BD-22deg3467, a DAO-type Star Exciting the Nebula Abell 35

    Science.gov (United States)

    Ziegler, M.; Rauch, T.; Werner, K.; Koppen, J.; Kruk, J. W.

    2013-01-01

    Spectral analyses of hot, compact stars with non-local thermodynamical equilibrium (NLTE) model-atmosphere techniques allow the precise determination of photospheric parameters such as the effective temperature (T(sub eff)), the surface gravity (log g), and the chemical composition. The derived photospheric metal abundances are crucial constraints for stellar evolutionary theory. Aims. Previous spectral analyses of the exciting star of the nebula A35, BD-22deg3467, were based on He+C+N+O+Si+Fe models only. For our analysis, we use state-of-the-art fully metal-line blanketed NLTE model atmospheres that consider opacities of 23 elements from hydrogen to nickel. We aim to identify all observed lines in the ultraviolet (UV) spectrum of BD-22deg3467 and to determine the abundances of the respective species precisely. Methods. For the analysis of high-resolution and high signal-to-noise ratio (S/N) far-ultraviolet (FUSE) and UV (HST/STIS) observations, we combined stellar-atmosphere models and interstellar line-absorption models to fully reproduce the entire observed UV spectrum. Results. The best agreement with the UV observation of BD-22deg3467 is achieved at T(sub eff) = 80 +/- 10 kK and log g = 7.2 +/- 0.3. While T(sub eff) of previous analyses is verified, log g is significantly lower. We re-analyzed lines of silicon and iron (1/100 and about solar abundances, respectively) and for the first time in this star identified argon, chromium, manganese, cobalt, and nickel and determined abundances of 12, 70, 35, 150, and 5 times solar, respectively. Our results partially agree with predictions of diffusion models for DA-type white dwarfs. A combination of photospheric and interstellar line-absorption models reproduces more than 90% of the observed absorption features. The stellar mass is M approx. 0.48 Solar Mass. Conclusions. BD.22.3467 may not have been massive enough to ascend the asymptotic giant branch and may have evolved directly from the extended horizontal branch

  10. IL PORTFOLIO EUROPEO PER LA FORMAZIONE INIZIALE DEGLI INSEGNANTI (PEFIL COME STRUMENTO DI INSEGNAMENTO/APPRENDIMENTO

    Directory of Open Access Journals (Sweden)

    Adriana Arcuri

    2013-01-01

    Full Text Available Scopo di questo contributo è  descrivere il modo in cui il Pefil , Portfolio europeo per la formazione iniziale degli insegnanti di lingue. Uno strumento di riflessione (ECML, 2007 è stato usato nell’ambito del “Master in didattica dell’italiano come lingua non materna” dell’Università di Palermo non solo come strumento di autovalutazione, ma anche come strumento di insegnamento/apprendimento, valorizzando cioè  le potenzialità formative di questo Portfolio come auspicato dagli stessi autori.Il documento è impiegato, in una nuova prospettiva, come chiave di lettura dei contenuti della professione e ha fornito ai corsisti uno strumento per rintracciare le connessioni fra i diversi input formativi del Master. In questo modo è stato possibile per ciascuno di loro costruire un tessuto unitario di apprendimento delle competenze professionali di insegnanti di italiano L2 e LS  in un’ottica di life long learning, secondo un approccio riflessivo.  The Portfolio Europeo per la Formazione Iniziale degli Insegnanti (PEFIL as a teaching/learning tool The aim of this paper is to describe how the European Portfolio for Student Teachers of Languages - Portfolio Europeo per la Formazione Iniziale degli Insegnanti (PEFIL, A reflection tool for language teacher education (ECML, 2007 has been used in the Master Degree program in “Italian Foreign Language Teaching” at the University of Palermo. The PEFIL has not only been used as a tool for self-assessment, but by exploiting the educational potential of the portfolio, it has also become an important learning/teaching tool.The Portfolio was used as a way to interpret essential teaching contents. It gave students a tool for finding connections between the diverse educational elements of the Master program. Thus it was possible for each of them to create a coherent network of professional competences for teaching Italian as a second and foreign language within a life long learning

  11. The phase relations in the Gd-Fe-Ga ternary system at 500 deg. C

    Energy Technology Data Exchange (ETDEWEB)

    Liu, D.C. [College of Materials Science and Engineering, Shenzhen University and Shenzhen Key Laboratory of Special Functional Materials, Shenzhen 518060 (China); Li, J.Q. [College of Materials Science and Engineering, Shenzhen University and Shenzhen Key Laboratory of Special Functional Materials, Shenzhen 518060 (China)], E-mail: junqinli@szu.edu.cn; Ouyang, M.; Liu, F.S.; Ao, W.Q. [College of Materials Science and Engineering, Shenzhen University and Shenzhen Key Laboratory of Special Functional Materials, Shenzhen 518060 (China)

    2009-06-24

    The isothermal section (500 deg. C) of the phase diagram of the Gd-Fe-Ga ternary system was investigated by X-ray powder diffraction analysis. Eleven binary compounds, GdGa{sub 2}, GdGa, Gd{sub 3}Ga{sub 2}, Gd{sub 5}Ga{sub 3}, GdFe{sub 2}, GdFe{sub 3}, Gd{sub 2}Fe{sub 17}, Fe{sub 3}Ga, Fe{sub 6}Ga{sub 5}, Fe{sub 3}Ga{sub 4} and FeGa{sub 3}, have been confirmed. Two ternary compounds, GdFe{sub 5.3}Ga{sub 6.7} and GdFe{sub 5}Ga{sub 7}, were found in this ternary system at 500 deg. C. The compound GdFe{sub 5.3}Ga{sub 6.7} is orthorhombic ScFe{sub 6}Ga{sub 6}-type structure (space group Immm) with a = 0.8567 (9), b = 0.86960 (9) and c = 0.50782 (5) nm, while the compound GdFe{sub 5}Ga{sub 7} is tetragonal ThMn{sub 12}-type structure (space group I4/mmm) with a = 0.8651(1) and c = 0.50934 (6) nm. The isothermal section at 500 deg. C consists of 16 single-phase regions, 31 two-phase regions and 16 three-phase regions. The maximum solid solubilities of Ga in GdFe{sub 2}, GdFe{sub 3}, Gd{sub 2}Fe{sub 17} are 9.2, 9.0, and 44.3 at.% respectively. The homogeneity range of GdGa{sub 2} is from 22 to 33.3 at.% Ga in Gd-Ga side but the solid solubility of Fe in this compound is very small. The homogeneity range of GdFe{sub 5}Ga{sub 7} is from 53.8 to 59.2 at.% Ga. Very limited solid solutions were measured in the other compounds.

  12. Gian Piero Piretto, La vita privata degli oggetti sovietici. 25 storie da un altro mondo

    Directory of Open Access Journals (Sweden)

    Enza Dammiano

    2013-05-01

    Full Text Available Dopo aver analizzato le “mitologie culturali” dell’era sovietica – il “radioso avvenire” che queste proiettavano (Il radioso avvenire. Mitologie culturali sovietiche, Einaudi, 2001 – e ‘illustrato’, in particolare, gli anni Trenta e Quaranta attraverso Gli occhi di Stalin (Raffaello Cortina, 2010, con La vita privata degli oggetti sovietici Gian Piero Piretto introduce il lettore nelle “storie” di venticinque «cose sovietiche» (32, disseminate lungo l’intero arco temporale di esistenza dell’URSS e oltre: «La maggior parte delle cose a cui dedicherò la mia specifica attenzione ancora circola […], talora in forme rinnovate (degenerate o adattate alla nuova realtà» (43.

  13. A 20 GHz Bright Sample for Delta > 72 deg - II. Multi-frequency Follow-up

    CERN Document Server

    Ricci, R; Verma, R; Prandoni, I; Carretti, E; Mack, K -H; Massardi, M; Procopio, P; Zanichelli, A; Gregorini, L; Mantovani, F; Gawronski, M P; Peel, M W

    2013-01-01

    We present follow-up observations at 5, 8 and 30 GHz of the K-band Northern Wide Survey (KNoWS) 20 GHz Bright Sample, performed with the 32-m Medicina Radio Telescope and the 32-m Torun Radio Telescope. The KNoWS sources were selected in the Northern Polar Cap (Delta > 72 deg) and have a flux density limit S(20GHz) = 115 mJy. We include NVSS 1.4 GHz measurements to derive the source radio spectra between 1.4 and 30 GHz. Based on optical identifications, 68 per cent of the sources are QSOs, and 27 per cent are radio galaxies. A redshift measurement is available for 58 per cent of the sources. The radio spectral properties of the different source populations are found to be in agreement with those of other high-frequency selected samples.

  14. Modeling and computation of flow in a passage with 360 deg turning and multiple airfoils

    Science.gov (United States)

    Shyy, W.; Vu, T. C.

    1991-06-01

    Numerical modeling of the three-dimensional flows in a spiral casing of a hydraulic turbine, containing a passage of 360-deg turning and multiple elements of airfoils (the so-called distributor), is made. The physical model is based on a novel two-level approach, comprising of (1) a global model that adequately accounts for the geometry of the spiral casing but smears out the details of the distributor and represents the multiple airfoils by a porous medium treatment; and (2) a local model that performs detailed analysis of flow in the distributor region. The global analysis supplies the inlet flow condition for the individual cascade of distributor airfoils, while the distributor analysis yields the information needed for modeling the characteristics of the porous medium. Comparisons of pressure and velocity profiles between measurement and prediction have been made to assess the validity of the present approach. Flow characteristics in the spiral casing are also discussed.

  15. Enhanced Disturbance-Observer-Based Control for a Class of Time-Delay System with Uncertain Sinusoidal Disturbances

    Directory of Open Access Journals (Sweden)

    Xinyu Wen

    2013-01-01

    Full Text Available This paper is concerned with disturbance-observer-based control (DOBC for a class of time-delay systems with uncertain sinusoidal disturbances. The disturbances are decomposed as precise and uncertain parts using nonlinear disturbance observer (DO after appropriate coordinate transformation. And then the two parts can be compensated by corresponding controller, respectively, such that the classic DOBC method is extended to uncertain disturbance rejection. One novel feature of the proposed method is that even if the precise disturbance parameters are inaccessible, the merits of DOBC can be inherited. By integrating the disturbance observers with feedback control laws with time delay, the disturbances can be rejected and the desired dynamic performances can be guaranteed. Finally, simulations for a flight control system are given to demonstrate the effectiveness of the results.

  16. Analysis of Thin Walled Wavy Shell of Monge Type Surface with Parabola and Sinusoid Curves by Variational-Difference Method

    Directory of Open Access Journals (Sweden)

    Ivanov Vyacheslav

    2017-01-01

    Full Text Available The paper is about the stress-strain state of the thin shell in the form of Monge surface with parabola generatrix and sinusoid guide. Coordinate system of the Monge surface is a system of coordinate lines of the principal curvatures of the surface. The variational-difference method is used for analysis. Variational-difference method allows using the geometric characteristics of the middle surface of the shell, which is important in the calculation of shells of complex shape. In the finite element method, which is often used in the shells of complex shape analysis, the equation of the middle surface of the shell is used only for finite element mesh.

  17. Imágenes débilmente confluentes de la curva sinusoidal del topólogo

    Directory of Open Access Journals (Sweden)

    Sergio Macías

    2009-12-01

    Full Text Available En el presente trabajo se caracterizan las imágenes débilmente confluentes de la curva del topólogo. Se demuestra que si G es la curva sinusoidal del topólogo y f : S → Y es una función débilmente confluente, donde Y es un continuo, entonces Y es o un arco, o una curva cerrada simple, o una compactación de [0, ∞ cuyo residuo es un arco o una curva cerrada simple. Más aún, si Y es alguno de estos continuos y f : S → Y es una función continua y sobreyectiva, se dan condiciones para que f sea débilmente confluente.

  18. Imágenes débilmente confluentes de la curva sinusoidal del topólogo

    Directory of Open Access Journals (Sweden)

    Sergio Macías

    2009-01-01

    Full Text Available En el presente trabajo se caracterizan las imágenes débilmente confluentes de la curva del topólogo. Se demuestra que si G es la curva sinusoidal del topólogo y f : S → Y es una función débilmente confluente, donde Y es un continuo, entonces Y es o un arco, o una curva cerrada simple, o una compactación de [0, ∞ cuyo residuo es un arco o una curva cerrada simple. Más aún, si Y es alguno de estos continuos y f : S → Y es una función continua y sobreyectiva, se dan condiciones para que f sea débilmente confluente.

  19. Adaptive backstepping control, synchronization and circuit simulation of a 3-D novel jerk chaotic system with two hyperbolic sinusoidal nonlinearities

    Directory of Open Access Journals (Sweden)

    Vaidyanathan Sundarapandian

    2014-09-01

    Full Text Available In this research work, a six-term 3-D novel jerk chaotic system with two hyperbolic sinusoidal nonlinearities has been proposed, and its qualitative properties have been detailed. The Lyapunov exponents of the novel jerk system are obtained as L1 = 0.07765,L2 = 0, and L3 = −0.87912. The Kaplan-Yorke dimension of the novel jerk system is obtained as DKY = 2.08833. Next, an adaptive backstepping controller is designed to stabilize the novel jerk chaotic system with two unknown parameters. Moreover, an adaptive backstepping controller is designed to achieve complete chaos synchronization of the identical novel jerk chaotic systems with two unknown parameters. Finally, an electronic circuit realization of the novel jerk chaotic system using Spice is presented in detail to confirm the feasibility of the theoretical model

  20. Manifestations and management of veno-occlusive disease/sinusoidal obstruction syndrome in the era of contemporary therapies.

    Science.gov (United States)

    Tewari, Priti; Wallis, Whitney; Kebriaei, Partow

    2017-02-01

    The concept of veno-occlusive disease (VOD), along with our understanding of it, has historically been and remains an evolving phenomenon. This review presents a broad view of VOD, also known as sinusoidal obstruction syndrome (SOS), including (1) traditional hematopoietic stem cell transplant-associated VOD/SOS, (2) late-onset VOD/SOS, (3) pulmonary VOD, and (4) VOD/SOS associated with chemotherapy only. Several VOD/SOS management modalities exist that include modes for both prophylaxis and treatment. An extensive review of the literature on monoclonal antibodies, both approved and pending approval by the US Food and Drug Administration, reveals that only a few have been associated with an increased risk for VOD/SOS. In fact, bevacizumab appears to have a protective effect against the development of VOD/SOS. As the landscape of cancer treatment changes, careful attention needs to be focused on how new therapies affect the incidence of VOD/SOS.

  1. Study of Heat Transfer with Nonlinear Thermal Radiation on Sinusoidal Motion of Magnetic Solid Particles in a Dusty Fluid

    Science.gov (United States)

    Bhatti, M. M.; Zeeshan, A.; Ellahi, R.

    2016-09-01

    In this article, heat transfer with nonlinear thermal radiation on sinusoidal motion of magnetic solid particles in a dust Jeffrey fluid has been studied. The effects of Magnetohydrodynamic (MHD) and hall current are also taken under consideration. The governing equation of motion and energy equation are modelled with help of Ohms law for fluid and dust phases. The solutions of the resulting ordinary coupled partial differential equations are solved analytically. The impact of all the physical parameters of interest such as Hartmann number, slip parameter, Hall parameter, radiation parameter, Prandtl number, Eckert number and particle volume fraction are demonstrated mathematically and graphically. Trapping mechanism is also discussed in detail by drawing contour lines. The present analysis affirms many interesting behaviours, which permit further study on solid particles motion with heat and mass transfer.

  2. Nonlinear response of a unidirectional erbium-doped fiber ring laser to a sinusoidally modulated pump power

    Science.gov (United States)

    Sola, I. J.; Martín, J. C.; Álvarez, J. M.

    2002-11-01

    The response of a unidirectional erbium-doped fiber ring laser, excited by a sinusoidally modulated pump power, is analyzed both experimentally and theoretically. Experimentally, several resonance peaks are observed, as well as different frequency ranges showing bistable behaviour. Appearance of all resonance peaks obtained can be explained taking into account simple relations between the pump modulation frequency and the system natural frequency. Theoretically, it is shown how a model which combines the theory of erbium-doped fibers and the semiclassical laser treatment can account for all phenomena observed, with good agreement. In particular, it is demonstrated that a correct description of the bistable regions requires taking into account powers and population distributions along the laser active medium.

  3. Phase-locking and chaos in a silent Hodgkin-Huxley neuron exposed to sinusoidal electric field

    Energy Technology Data Exchange (ETDEWEB)

    Che Yanqiu [School of Electrical Engineering and Automation, Tianjin University, 300072 (China); Wang Jiang [School of Electrical Engineering and Automation, Tianjin University, 300072 (China)], E-mail: jiangwang@tju.edu.cn; Si Wenjie; Fei Xiangyang [School of Electrical Engineering and Automation, Tianjin University, 300072 (China)

    2009-01-15

    Neuronal firing patterns are related to the information processing in neural system. This paper investigates the response characteristics of a silent Hodgkin-Huxley neuron to the stimulation of externally-applied sinusoidal electric field. The neuron exhibits both p:q phase-locked (i.e. a periodic oscillation defined as p action potentials generated by q cycle stimulations) and chaotic behaviors, depending on the values of stimulus frequencies and amplitudes. In one-parameter space, a rich bifurcation structure including period-adding without chaos and phase-locking alternated with chaos suggests frequency discrimination of the neuronal firing patterns. Furthermore, by mapping out Arnold tongues, we partition the amplitude-frequency parameter space in terms of the qualitative behaviors of the neuron. Thus the neuron's information (firing patterns) encodes the stimulus information (amplitude and frequency), and vice versa.

  4. Silica enhanced formation of hydroxyapatite nanocrystals in simulated body fluid (SBF) at 37 deg. C

    Energy Technology Data Exchange (ETDEWEB)

    Sadjadi, M.S., E-mail: m.s.sadjad@gmail.com [Department of Chemistry, Sciences and Research Branch, Islamic Azad University, Tehran (Iran, Islamic Republic of); Ebrahimi, H.R. [Department of Chemistry, Sciences and Research Branch, Islamic Azad University, Tehran (Iran, Islamic Republic of); Meskinfam, M. [Department of Chemistry, Tonekabon Branch, Islamic Azad University, Tonekabon (Iran, Islamic Republic of); Zare, K. [Department of Chemistry, University of Shahid Beheshti, Eveen Tehran (Iran, Islamic Republic of)

    2011-10-17

    Highlights: {yields} We report on fast formation of hexagonal nanocrystals of calcium hydroxyapatite (HA) in silica-containing simulated body fluid solution at 37 deg. C. {yields} Bioactivity and biodegradability of TCP precursor have been confirmed by the dissolution of TCP and formation of a bone like layer of new HA nanoparticles outside of the precursor after 24 h soaking in SBF solution. {yields} Successive nucleation and formation of tiny hexagonal HA nanoplates and nanorods have been confirmed by TEM results after 24 h soaking of TCP in silica-containing BSF solution. - Abstract: The chemical modification of implant (prosthesis) surfaces is being investigated worldwide for improving the fixation of orthopaedic and dental implants. The main goal in this surface modification approach is to achieve a faster bone growth and chemical bonding of the implant to the newly generated and/or remodeled bone. In this work, we report fast formation of hexagonal nanocrystals of calcium hydroxyapatite (HA) in simulated body fluid (SBF, inorganic components of human blood plasma) solutions at 37 deg. C, using calcium phosphate (TCP) and sodium silicate as precursors. Characterization and chemical analysis of the synthesized powders were performed by Fourier transform infrared spectroscopy (FT-IR), X-ray powder diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The results indicated enhanced nucleation and formation of bone like layer of HA nanocrystals at the surface of TCP nanoparticles and occurrence of HA nanocrystals during 24 h soaking of TCP in SBF solution containing silica ions. The average size of a nanoparticle, using Scherrer formula, was found to be 18.2 nm.

  5. An Approximate Solution to the Equation of Motion for Large-Angle Oscillations of the Simple Pendulum with Initial Velocity

    Science.gov (United States)

    Johannessen, Kim

    2010-01-01

    An analytic approximation of the solution to the differential equation describing the oscillations of a simple pendulum at large angles and with initial velocity is discussed. In the derivation, a sinusoidal approximation has been applied, and an analytic formula for the large-angle period of the simple pendulum is obtained, which also includes…

  6. An Approximate Solution to the Equation of Motion for Large-Angle Oscillations of the Simple Pendulum with Initial Velocity

    Science.gov (United States)

    Johannessen, Kim

    2010-01-01

    An analytic approximation of the solution to the differential equation describing the oscillations of a simple pendulum at large angles and with initial velocity is discussed. In the derivation, a sinusoidal approximation has been applied, and an analytic formula for the large-angle period of the simple pendulum is obtained, which also includes…

  7. Effect of Substrate Doping in Relaxed SiGe Buffers on Strained Si 2DEG Quantum Devices

    Science.gov (United States)

    Yao, Kun; Gaevski, Mikhail; Chernyshov, Alexander; Rokhinson, Leonid; Mike, Curtin; Park, Ji-Soo; Fiorenza, James; Lochtefeld, Anthony; Sturm, James

    2009-03-01

    We describe the impact of Si substrate doping on the substrate leakage in strained Si two-dimensional electron gases (2DEG) on SiGe relaxed graded buffers and on quantum devices fabricated from the 2DEG. The best commercially available high quality SiGe relaxed buffers with 30% Ge content, grown at temperature above 1000^oC, have very low threading dislocation density (heterostructures were grown at 625-700^oC in a rapid thermal chemical vapor deposition (RTCVD). However, it is shown that the substrate doping (Arsenic) contributes to leakage current origin in relaxed buffers at liquid helium temperatures if the starting Si substrate is heavily doped (˜5E17cm-2). The leakage can be attributed to enhanced dopant diffusion along misfit dislocations and high diffusion rate of As in SiGe. The leakage current makes side gating of nanostructures in the 2DEG impossible. With a lightly doped substrate, to avoid leakage, we achieved a high quality 2DEG and successful side gating of a 2DEG quantum dot for a quantum point contact. This work is supported by the NSA under ARO contract number W911NF-05-1-0437.

  8. Decomposition of Head-Related Transfer Functions into Multiple Damped and Delayed Sinusoidals

    Science.gov (United States)

    Faller, Kenneth John; Barreto, Armando; Adjouadi, Malek

    There are currently two options to achieve binaural sound spatialization using Head-Related Impulse Responses (HRIRs): measure every intended listener's HRIR or use generic HRIRs. However, measuring HRIRs requires expensive and specialized equipment, which removes its availability to the general public. In contrast, use of generic HRIRs results in higher localization errors. Another possibility that researchers, including our group, are pursuing is the customization of HRIRs. Our group is pursuing this by developing a structural model in which the physical measurements of a new intended listener could be used to synthesize his/her custom-fitted HRIRs, to achieve spatialization equivalent to measured HRIRs. However, this approach requires that HRIRs from multiple subjects be initially broken down in order to reveal the parameters of the corresponding structural models. This paper presents a new method for decomposing HRIRs and tests its performance on simulated examples and actual HRIRs.

  9. Detailed 1 x 1 deg gravimetric Indian Ocean geoid and comparison with GEOS-3 radar altimeter geoid profiles

    Science.gov (United States)

    Kahle, H.-G.; Chapman, M.; Talwani, M.

    1978-01-01

    A new set of 1 x 1 deg mean free-air anomalies in the Indian Ocean is determined on the basis of previously published free-air anomaly maps (Talwani and Kahle, 1975) and the most recent Lamont surface ship gravity measurements. The data are then used to compute a (total) 1 x 1 deg gravimetric Indian Ocean geoid. The computation is carried out by combining the Goddard Space Flight Center (GSFC) GEM-6 geoid and a difference geoid that corresponds to the differences between the set of 1 x 1 deg surface gravity values and the GEM-6 gravity anomalies. The difference geoid is highest over the Madagascar Ridge (+20 m) and lowest over the Timor Trough (-30 m). The total geoid is compared with GEOS-3 radar altimeter-derived geoid profiles, and geophysical implications are discussed.

  10. Results of steel corrosion tests in flowing liquid Pb/Bi at 420-600 deg. C after 2000 h

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, G. E-mail: georg.mueller@ihm.fzk.de; Heinzel, A.; Konys, J.; Schumacher, G.; Weisenburger, A.; Zimmermann, F.; Engelko, V.; Rusanov, A.; Markov, V

    2002-02-01

    Corrosion tests were carried out on austenitic AISI 316L and 1.4970 steels and on MANET steel up to 2000 h of exposure to flowing (up to 2 m/s) Pb/Bi. The concentration of oxygen in the liquid alloy was controlled at 10{sup -6} wt%. Specimens consisted of tube and rod sections in original state and after alloying of Al into the surface. After 2000 h of exposure at 420 and 550 deg. C the specimen surfaces were covered with an intact oxide layer which provided a good protection against corrosion attack of the liquid Pb/Bi alloy. After the same time corrosion attack at 600 deg. C was severe at the original AISI 316L steel specimens. The alloyed specimens containing FeAl on the surface of the alloyed layer still maintained an intact oxide layer with good corrosion protection up to 600 deg. C.

  11. Narrow multibeam satellite ground station antenna employing a linear array with a geosynchronous arc coverage of 60 deg. I - Theory

    Science.gov (United States)

    Amitay, N.; Gans, M. J.

    1982-11-01

    The feasibility of using an appropriately squinted linear scan in narrow multibeam satellite ground station antennas employing phased arrays is demonstrated. This linear scan has the potential of reducing the complexity of a narrow-beam planar array to that of a linear array. Calculations for such antennas placed at cities throughout the U.S. show that the peak beam pointing error in covering the 70 deg W to 130 deg W geosynchronous equatorial arc (GEA) is under 5/1000th of a degree. Communication at a 300 MBd rate in the 12/14 GHz band can be made feasible, for a grating lobe-free scan and 0.5 deg beamwidth antenna, by using a relatively simple time equalization.

  12. Development of a new correlation for estimating pool boiling heat transfer coefficient of MEG/DEG/water ternary mixture

    Directory of Open Access Journals (Sweden)

    Sarafraz M.M.

    2012-01-01

    Full Text Available Pool boiling heat transfer coefficient of monoethylene glycol (MEG, diethylene glycol (DEG and water ternary mixtures has been experimentally measured up to heat flux 114 kW/m2 at various volumetric concentrations of MEG and DEG. As expected, heat transfer coefficient was strongly taken as a direct function of heat flux. Existing well-known correlations are shown to be unable to predict the acceptable values for the tested ternary mixtures, particularly at different concentrations of MEG and DEG. Furthermore, a new modified correlation is developed on the basis of the Stephan - Preußer correlation that predicts the values of heat transfer coefficients with absolute average error of about 7% that is reasonable and acceptable values in compare to other existing correlations.

  13. 基于Duffing振子的弱正弦信号检测方法研究%A New Weak Sinusoidal Signal Detection Method Based on Duffing Oscillators

    Institute of Scientific and Technical Information of China (English)

    刘海波; 吴德伟; 戴传金; 毛虎

    2013-01-01

    数值仿真发现,通过设置Duffing振子初值和参考信号初相使其满足一定关系,Duffing振子从大周期态向混沌态的转变(正向相变),比较其从混沌态向大周期态的转变(逆向相变),对周期策动力的幅值体现出了更稳健的敏感性.据此,提出了一种利用Duffing振子逆向相变实现弱正弦信号检测的方法,分析了其可行性,并通过仿真与传统的检测方法进行了对比.数据表明,相同条件下,所提检测方法具有更高的检测精度.此外,根据相空间分布特点,提出了一种相轨迹运动状态的判别方法.该判别方法计算量小,并具有较好的实时性,通过仿真验证了该方法的正确性.%It is found in numerical simulations that Duffing oscillator state transition from big-cycle motion to chaotic motion has more robust sensitivity to the amplitude of the forced periodic term than the transition from chaotic motion to big-cycle motion, as long as the reference signal initial phase and the Duffing oscillator initial value are matched.On this basis,a new weak sinusoidal signal detection scheme is advanced, whose feasibility is then analyzed.The advanced scheme shows higher detection capability by comparing with traditional methods.Besides, considering the characteristics of the Duffing oscillator phase space, a new Duffing oscillator motion state judging method is proposed, which features good real-time performance and low computational complexity, and is verified with simulations.

  14. Prevalence of Deg Nala disease in eastern India and its reproduction in buffaloes by feeding Fusarium oxysporum infested rice straw

    Institute of Scientific and Technical Information of China (English)

    P Dandapat; PK Nanda; S Bandyopadhyay; Anmol Kaushal; A Sikdar

    2011-01-01

    Objective: To undertake a study on prevalence of Deg Nala disease in eastern states of India and to reproduce the disease in buffaloes by the Fusarium spp., isolated from the affected region.Methods:During this investigation, a survey was conducted covering four states of eastern region to identify the Deg Nala cases as well as to isolate and characterize the causative agent(s). An experimental study was carried out to reproduce the disease in healthy male buffaloes (2-3 years age) by randomly dividing them into five groups (four in each group). Each individual group was fed with rice straw artificially infested with either of the two representative isolates ofFusarium oxysporum (F. oxysporum) (F01, F02) or representative reference strains of Fusarium equiseti (F. equiseti) (ITCCF-2470) and Fusarium moniliforme (F. moniliforme) (ITCCF-4821) for 30 days, whereas the control group was fed with normal rice straw only. Results: A total of 658 Deg Nala cases were recorded and 12 Fusarium isolates were identified from the mouldy rice straw collected from these affected areas. The characterization of the isolates revealed three species viz., F. oxysporum, F. equiseti and F. moniliforme, among which F. oxysporum was predominant. The disease was artificially reproduced in three buffaloes in F01 group and one in F02 group within 20-23 days by feeding F. oxysporum infested rice straw which resembled the clinical symptoms and gross lesions of natural Deg Nala cases. Conclusions: The field investigation and laboratory studies, including experimental production of Deg Nala disease suggest the possible involvement of mycotoxins. However, further investigations needs to be done to understand nature of the toxic factors involved in production of the Deg Nala disease.

  15. Convective heat-transfer rate distributions over a 140 deg blunt cone at hypersonic speeds in different gas environments

    Science.gov (United States)

    Stewart, David A.; Chen, Y. K.

    1993-01-01

    Experiments were conducted in air, CO2, and CO2-argon gas mixtures to obtain heating distribution data over a 140 deg blunt cone with various corner radii. The effect of corner radius on the heating distribution over the forebody of the cone was included in the investigation. These experiments provide data for validation of two-dimensional axisymmetric and three-dimensional Navier-Stokes solutions. Heating distribution data and measured bow shock wave stand-off distances for 0 deg angle of attack were compared with predicted values using a two-dimensional axisymmetric Navier-Stokes code.

  16. Improvement of Weak Sinusoidal Signal Detecting Based on Duffing Oscillator%基于Duffing振子的弱正弦信号检测的改进

    Institute of Scientific and Technical Information of China (English)

    任志玲; 刘银报; 史旭鹏

    2011-01-01

    A new algorithm is proposed for weak sinusoidal signal detecting based on Duffing chaotic oscillator. In order to detect frequency of weaker sinusoidal signal, we adjust the parameters of Duffing system to make the threshold of Duffing system and the amplitude of weak sinusoidal signal at the same level. Furthermore, we make the threshold of Duffing system small by changing relative parameters of Duffing system, reduce the oscillator frequency ratio among oscillators, and increase the number of oscillators to get higher accuracy. Numerical simulation shows it can detect as low as 0. 002V weak amplitude sinusoidal signal.%提出了一种基于Duffing混沌振子弱正弦信号的检测方法;为了能够检测更加微弱正弦信号的频率,对Duffing系统相关参数加以调整,使系统阈值与微弱正弦信号幅值大致相当;采用Duffing振子阵列法检测微弱正弦信号频率,在检测精度较高的前提下,缩小振子间频率比,增加振子数量;实验仿真表明可以检测幅值最低为0.002V的弱正弦信号.

  17. Fokker-Planck and Fortet equation-based parameter estimation for a leaky integrate-and-fire model with sinusoidal and stochastic forcing

    DEFF Research Database (Denmark)

    Iolov, Alexandre; Ditlevsen, Susanne; Longtin, Andrë

    2014-01-01

    Analysis of sinusoidal noisy leaky integrate-and-fire models and comparison with experimental data are important to understand the neural code and neural synchronization and rhythms. In this paper, we propose two methods to estimate input parameters using interspike interval data only. One is based...

  18. A transgenic model for conditional induction and rescue of portal hypertension reveals a role of VEGF-mediated regulation of sinusoidal fenestrations.

    Directory of Open Access Journals (Sweden)

    Dalit May

    Full Text Available Portal hypertension (PH is a common complication and a leading cause of death in patients with chronic liver diseases. PH is underlined by structural and functional derangement of liver sinusoid vessels and its fenestrated endothelium. Because in most clinical settings PH is accompanied by parenchymal injury, it has been difficult to determine the precise role of microvascular perturbations in causing PH. Reasoning that Vascular Endothelial Growth Factor (VEGF is required to maintain functional integrity of the hepatic microcirculation, we developed a transgenic mouse system for a liver-specific-, reversible VEGF inhibition. The system is based on conditional induction and de-induction of a VEGF decoy receptor that sequesters VEGF and preclude signaling. VEGF blockade results in sinusoidal endothelial cells (SECs fenestrations closure and in accumulation and transformation of the normally quiescent hepatic stellate cells, i.e. provoking the two processes underlying sinusoidal capillarization. Importantly, sinusoidal capillarization was sufficient to cause PH and its typical sequela, ascites, splenomegaly and venous collateralization without inflicting parenchymal damage or fibrosis. Remarkably, these dramatic phenotypes were fully reversed within few days from lifting-off VEGF blockade and resultant re-opening of SECs' fenestrations. This study not only uncovered an indispensible role for VEGF in maintaining structure and function of mature SECs, but also highlights the vasculo-centric nature of PH pathogenesis. Unprecedented ability to rescue PH and its secondary manifestations via manipulating a single vascular factor may also be harnessed for examining the potential utility of de-capillarization treatment modalities.

  19. Valutazione dell'affidabilità degli operatori per l'identificazione microscopica di peli di mammiferi

    Directory of Open Access Journals (Sweden)

    Paolo Ciucci

    2003-10-01

    Full Text Available La quantificazione dei resti indigesti contenuti negli escrementi è tra le tecniche più frequentemente utilizzate per studiare la dieta del lupo, dove il riconoscimento delle specie preda, nel caso dei mammiferi, si basa su caratteristiche microscopiche distintive del pelo. Tale tecnica, è tuttavia soggetta ad errori individuali nonostante l'esperienza dell'operatore e il ricorso a testi o collezioni di riferimento. Congiuntamente ad una mancata standardizzazione delle procedure di preparazione e trattamento del campione, queste fonti di errore possono alterare significativamente i risultati. Nell'ambito di un progetto UE-Life sull'ecologia del Lupo, in tre Parchi Regionali dell'Emilia-Romagna (2001-2004, abbiamo quindi applicato una procedura standardizzata per la selezione, raccolta, preparazione e trattamento dei campioni fecali di lupo ai fini dell'analisi della dieta. A tal fine è stato organizzato un corso di formazione da parte di docenti qualificati per un totale di 150 ore, suddiviso in moduli e articolato in esercitazioni e prove pratiche di autovalutazione. Al corso, e dopo un ulteriore periodo di esercitazioni individuali (ca. 300 ore/operatore, è quindi seguito un esame di identificazione che ha permesso di quantificare l'affidabilità di ciascun operatore. Il test per l'identificazione a livello di specie è stato basato su un campione di 120 peli, la cui specie di origine era ignota ai candidati (blind test, suddivisi tra ungulati selvatici (n=54: Capriolo, Cervo, Daino, Muflone, Cinghiale, ungulati domestici (n=21: bovini, ovini, caprini, equini, canidi (n= 18: lupo, cane, volpe e altre specie (n=27: lepre, marmotta, tasso, martora, faina, puzzola, gatto, scoiattolo, talpa, muridi. Un sottocampione di 65 peli è stato utilizzato per valutare l'affidabilità nel riconoscimento delle classi d'età (< 5 mesi, ≥ 5 mesi per le sole categorie degli ungulati selvatici (n=54 e degli

  20. Perturbation Theory for PT-Symmetric Sinusoidal Optical Lattices at the Symmetry-Breaking Threshold

    CERN Document Server

    Jones, H F

    2011-01-01

    The $PT$ symmetric potential $V_0[\\cos(2\\pi x/a)+i\\lambda\\sin(2\\pi x/a)]$ has a completely real spectrum for $\\lambda\\le 1$, and begins to develop complex eigenvalues for $\\lambda>1$. At the symmetry-breaking threshold $\\lambda=1$ some of the eigenvectors become degenerate, giving rise to a Jordan-block structure for each degenerate eigenvector. In general this is expected to give rise to a secular growth in the amplitude of the wave. However, it has been shown in a recent paper by Longhi, by numerical simulation and by the use of perturbation theory, that for an initial wave packet this growth is suppressed, giving instead a constant maximum amplitude. We revisit this problem by developing the perturbation theory further. We verify that the results found by Longhi persist to second order, and with different input wave packets we are able to see the seeds in perturbation theory of the phenomenon of birefringence first discovered by El-Ganainy et al.

  1. Il disagio degli insegnanti tra psicologia e pedagogia: una indagine multidimensionale sul fenomeno del burnout

    Directory of Open Access Journals (Sweden)

    Francesca Botticelli

    2012-06-01

    Full Text Available A partire da un minuzioso esame della letteratura internazionale sui diversi versanti che costituiscono gli elementi chiave di questa ricerca (stress lavoro-correlato, burnout, formazione insegnanti il lavoro vuole analizzare il fenomeno del burnout degli insegnanti come fenomeno multi dimensionale. Si raggiunge questo obiettivo a partire dalla concezione del burnout come risultato di stress lavoro-correlato che si muove su dimensioni plurime, aventi carattere sia soggettivo che organizzativo. Per l‘apprezzamento delle prime sono stati utilizzati il Maslach Burnout Inventory (Maslach e Jackson 1986; validazione italiana Sirigatti e Stefanile, 1993; sul versante della salute organizzativa il Multidimensional Organizational Health Questionnaire (MOHQ; Avallone e Paplomatas 2005; sul versante dei principali sintomi lamentati dal campione di ricerca la Sympton Check List (SCL-90; Derogatis, 1977 e infine sulla percezione di sé Adjective Check List (ACL; Gough 1949; valid. It. Gough, Heilbrun, e Fioravanti, 1980 nella modalità di Sé reale . Il campione era costituito da 52 docenti di cui 28 maschi (53,8% e 24 femmine (46,2%. 50 anni l‘età media dei soggetti interpellati. L‘analisi dei risultati mostra la necessità di soluzioni al problema secondo più dimensioni e anche di una lettura pedagogica del fenomeno nel suo intrecciarsi con le dinamiche alla base della socialità contemporanea. Tale lettura e le soluzioni proposte si inscrivono infatti nel contesto ampio delle trasformazioni che investono a livello globale il mondo dell‘istruzione e la società nel suo complesso, generando un disagio che si coagula intorno alla perdita di senso del proprio essere nel mondo, quindi anche sul senso delle attività lavorative e dell‘educazione. Il contributo pedagogico è orientato quindi alla ricerca di senso da un lato, e al contrasto a livello istituzionale di pratiche volte a fare dell‘educazione un mercato e del suo assessment uno

  2. ELABORAZIONE DI UN QUESTIONARIO PER LA RILEVAZIONE DEI BISOGNI COMUNICATIVI DEGLI ADULTI IMMIGRATI

    Directory of Open Access Journals (Sweden)

    Annamaria Aquilino

    2012-02-01

    Full Text Available L’intensità del fenomeno migratorio in Italia suscita una riflessione critica sui bisogni linguistici di un  nuovo pubblico di apprendenti, spinti verso la conoscenza della lingua italiana da una forte esigenza di integrazione sociale. L’articolo presenta l’elaborazione di un questionario come strumento d’indagine essenziale per la rilevazione dei bisogni comunicativi degli immigrati adulti. Progettato nell’ambito di un corso di italiano L2  presso il CTP di Rozzano (Milano e sottoposto a un campione di 24 stranieri, il questionario si  è rivelato molto utile per la definizione del profilo dei singoli apprendenti e dell’intera classe che, caratterizzata da una grande differenziazione, non è sempre facile da gestire. L’interpretazione finale dei dati ha messo in luce non solo gli elementi di diversità ma ha anche permesso di cogliere alcuni tratti omogenei molto interessanti, indispensabili per la programmazione del percorso didattico, che sarà tanto efficace quanto più si adatterà alla realtà psicologica e socio-culturale degli apprendenti.     Questionnaire design to Survey the communicative needs of adult immigrants   Widespread immigration in Italy has brought about critical reflection on the linguistic needs of a new group of learners, highly motivated to learn the Italian language because of their strong need for social integration.  This article presents the designing of a questionnaire as an essential tool for surveying the communicative needs of adult immigrants.  Designed for an Italian L2 course held at the CTP in Rozzano (Milano and administered to 24 foreigners, the questionnaire was very useful for defining the profile of the single learners and the whole class group, which was dissimilar, and thus not the easiest to conduct.  The final interpretation of the data brought to light not only the elements of diversity but they also allowed us to recognize a few interesting common traits, essential for

  3. Non-Local Signal in Quasi-2DEG of LAO/STO

    Science.gov (United States)

    Jin, Mi-Jin; Moon, Seon Young; Modepalli, Vijayakumar; Jo, Junhyeon; Park, Jungmin; Baek, Seung-Hyub; Yoo, Jung-Woo

    2015-03-01

    Electron gas arizen at the insulating oxide interfaces exhibits high electron mobility, tunable carrier densities and related unique behaviors such as coexistence of superconductivity and ferromagnetism, Kondo resistance, etc. Itinerant electrons at the oxide hetero-interface are predicted to have long spin diffusion length, while they are under the relatively strong Rashba-type spin orbit coupling due to inversion symmetry breaking. We studied non-local spin signal induced by spin orbit coupling with additional gate-controlled Rashba field in quasi-2DEG of LaAlO3/SrTiO (LAO/STO) interface. We fabricated simple hall-bar like geometry to measure non-local signal with the variation of channel length (2 ~ 10 μm). Cleaned sample was patterned using e-beam lithography and reactive ion etching followed by oxygen treatment to anneal out oxygen vacancies. When an electric current flows one line of the hall bar structure, spin orbit coupling will induce the current flow away from the source current channel via spin hall and inverse spin hall effects. The non-local signals were studied under different angles of magnetic field and the variation of applied gate voltage. This work was supported by a grant from (No. 1.140092.01) funded by the Ulsan National Institute of Science and Technology.

  4. La ballata E5 e le sue varianti nel codice degli abbozzi

    Directory of Open Access Journals (Sweden)

    Giulia Ravera

    2016-07-01

    Full Text Available La ballata petrarchesca Amor, che ’n cielo e ’n cor gentile alberghi (E5, composta per il musico Confortino e destinata alla definitiva esclusione dal Canzoniere, è un componimento profondamente complesso, oltre che caratterizzato da un’intrigante vicenda redazionale. E5 appare infatti imperniata sull’ambiguità tra due poli opposti, amoroso e religioso, in un gioco di contrapposizioni che rende difficile scegliere in via definitiva tra un’interpretazione sentimentale ed una lettura morale o addirittura penitenziale. La ballata è inoltre caratterizzata dall’evidente ed esteso riuso della tradizione lirica ed in particolare dei modelli stilnovistici, non solo e non tanto sul piano degli stilemi e delle immagini, quanto in termini di concezione amorosa. Il rapporto con queste fonti risulta problematico, tra ripresa e negazione, e rappresenta un ulteriore nodo significativo rispetto all’interpretazione del componimento. La graduale evoluzione della ballata, di cui possono essere identificate per lo meno tre versioni distinte, sembra accentuare gli elementi di complessità e le sovrapposizioni semantiche. Infine, l’analisi formale e contenutistica di E5 favorisce la formulazione, pur senza pretesa di certezza, di ipotesi sulle ragioni della sua sorte extravagante

  5. Electrochemical characterisation of nickel-based alloys in sulphate solutions at 320 deg. C

    Energy Technology Data Exchange (ETDEWEB)

    Le Canut, J.-M.; Maximovitch, S. E-mail: suzanne.maximovitch@lepmi.inpg.fr; Dalard, F

    2004-08-15

    Nickel alloy steam generator tubes of pressurized water reactors (PWR) are sensitive to stress corrosion cracking (SCC) and the possibility of predicting SCC from electrochemical measurements is of considerable interest for nuclear industry. The electrochemical properties of several nickel-based alloys were studied at 320 deg. C in sulphate solutions at neutral or slightly alkaline pH from corrosion potential measurements, polarisation curves and polarisation resistance (R{sub p}) measurements by linear voltammetry and electrochemical impedance spectroscopy (EIS). The passive layers were much more stable in neutral conditions, due to the presence of chromium oxide, and alloys 600TT and 690 showed the best passivity. R{sub p} measurements confirmed that alloys 600TT and 690 have the lowest corrosion rates. At alkaline pH, the passivation currents were higher than those obtained at neutral pH, and the alloys showed a close behaviour. Reduction of sulphates to sulphides seemed to be possible. Results are in agreement with thermodynamic and surface analysis data of literature. The electrochemical stability did not appear to be directly related to SCC susceptibility since it varied inversely with the pH dependance of SCC in sulphate medium.

  6. A 20 GHz bright sample for {\\delta} > +72{\\deg}: I. Catalogue

    CERN Document Server

    Righini, S; Ricci, R; Zanichelli, A; Mack, K -H; Massardi, M; Prandoni, I; Procopio, P; Verma, R; López-Caniego, M; Gregorini, L; Mantovani, F

    2012-01-01

    During 2010-2011, the Medicina 32-m dish hosted the 7-feed 18-26.5 GHz receiver built for the Sardinia Radio Telescope, with the goal to perform its commissioning. This opportunity was exploited to carry out a pilot survey at 20 GHz over the area for {\\delta} > + 72.3{\\deg}. This paper describes all the phases of the observations, as they were performed using new hardware and software facilities. The map-making and source extraction procedures are illustrated. A customised data reduction tool was used during the follow-up phase, which produced a list of 73 confirmed sources down to a flux density of 115 mJy. The resulting catalogue, here presented, is complete above 200 mJy. Source counts are in agreement with those provided by the AT20G survey. This pilot activity paves the way to a larger project, the K-band Northern Wide Survey (KNoWS), whose final aim is to survey the whole Northern Hemisphere down to a flux limit of 50 mJy (5{\\sigma}).

  7. Effect of Cr content on the FAC of pipe material at 150 .deg. C

    Energy Technology Data Exchange (ETDEWEB)

    Park, Tae Jun; Kim, Hong Pyo [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2013-06-15

    Flow accelerated corrosion (FAC) of the carbon steel piping in nuclear power plants (NPPs) has been major issue in nuclear industry. During the FAC, a protective oxide layer on carbon steel dissolves into flowing water leading to a thinning of the oxide layer and accelerating corrosion of base material. As a result, severe failures may occur in the piping and equipment of NPPs. Effect of alloying elements on FAC of pipe materials was studied with rotating cylinder FAC test facility at 150 .deg. C and at flow velocity of 4m/s. The facility is equipped with on line monitoring of pH, conductivity, dissolved oxygen(DO) and temperature. Test solution was the demineralized water, and DO concentration was less than 1 ppb. Surface appearance of A 106 Gr. B which is used widely in secondary pipe in NPPs showed orange peel appearance, typical appearance of FAC. The materials with Cr content higher than 0.17wt.% showed pit. The pit is thought to early degradation mode of FAC. The corrosion product within the pit was enriched with Cr, Mo, Cu, Ni and S. But S was not detected in SA336 F22V with 2.25wt.% Cr. The enrichment of Cr and Mo seemed to be related with low, solubility of Cr and Mo compared to Fe. Measured FAC rate was compared with Ducreaux's relationship and showed slightly lower FAC rate than Ducreaux's relationship.

  8. Back Pain During 6 deg Head-Down Tilt Approximates That During Actual Microgravity

    Science.gov (United States)

    Hutchinson, Karen J.; Watenpaugh, Donald E.; Murthy, Gita; Convertino, Victor A.; Hargens, Alan R.

    1995-01-01

    Astronauts often experience back pain during spaceflight. It was found that during spaceflight, 14 of 19 Shuttle crewmembers experienced back pain, which they described as dull (62%), localized to the lower back (500/6), and with an intensity of 2 on a 5-point scale. Further, the spine lengthens 4-7 cm in microgravity. Our objective was to compare back pain and spinal lengthening (body height increase) during simulated microgravity (6 deg head-down tilt, HDT) with the some parameters during actual microgravity. Eight male subjects completed a modified McGill pain questionnaire with intensity graded from zero (no pain) to five (intense and incapacitating gain) each day at 7.-OO pm during 2 d pre-HDT control, 16 d HDT, and I d post-HDT recovery periods. Only 2 subjects reported any pain after day 9 of HDT and during recov- ery. Heights increased 2.1 t 0.5 cm by day 3 of HDT and re- mained at that level until the end of the HDT period. Although spinal lengthening in space is greater than that during HDT, the HDT model approximates the level, type, distribution, and time course of back pain associated with actual microgrovity. In the HDT model, pain subsides in intensity when spinal lengthening stops. Therefore, back pain in actual and simulated microgravity may result from stretching of spinal andlor paraspinal tissues until a new spinal length is reached.

  9. Estimating new production in the equatorial Pacific Ocean at 150 deg W

    Science.gov (United States)

    Dugdale, Richard C.; Wilkerson, Frances P.; Barber, Richard T.; Chavez, Francisco P.

    1992-01-01

    A major goal of the WEC88 cruise of the R/V Wecoma to the equatorial Pacific (made in February-March 1988) was to establish rates of new production along a meridional section at 150 deg W and to compare these measured rates with the relatively high values for the equatorial Pacific that had been reported previously using indirect methods and models. Production values were obtained from the traditional approach using N-15 labeled nitrate uptake, and by using C-14 fixation values multiplied by f (proportion of new production) from various sources: from N-15 data, from a C-14 fixation-versus-f relationship, or from a nitrate-versus-f relationship. The ratios of directly measured nitrate and carbon uptake and the ratios of nitrate to nitrate plus ammonium uptake, i.e., values of f, agree well; values of f calculated from carbon uptake or from nitrate concentration are overestimates for the equatorial upwelling region. Carbon-to-nitrogen uptake ratios measured with C-14 and N-15, respectively, approximate the Redfield molar ratio, 6.6 C:N. The overall mean value of f (0.17) helps confirm the view that the low primary production in the enriched eastern equatorial Pacific is due to failure of the nitrate-uptake system.

  10. Novalis e Pascal. L’influsso degli “antichi maestri” nelle opere di Thomas Bernhard

    Directory of Open Access Journals (Sweden)

    Stefano Apostolo

    2015-08-01

    Full Text Available L’elaborato si pone come obiettivo l’analisi degli influssi che due pensatori del calibro di Novalis e Pascal esercitarono sulla poetica e sulla produzione di Thomas Bernhard (1931-1989. Partendo da citazioni ricorrenti nei testi dell’autore, si passerà ad una loro contestualizzazione e ad un esame del ruolo che le due figure ricoprirono nella cosmogonia bernhardiana. Personalità di per sé molto diverse, poeta romantico il primo e teologo il secondo, vissute in epoche e contesti differenti, costituiscono tuttavia punti di riferimento fondamentali e ineludibili per la comprensione dei testi dell’autore austriaco. Novalis, teoreta di quella filosofia della malattia che così profondamente pervade le opere di Bernhard, influenzò fortemente la sua oscura poetica della morte e della Hoffnungslosigkeit, e proprio il frammento, l’unità minima e paradigmatica della produzione novalisiana, venne erto da Bernhard a modello compositivo, sia nella prosa che nel teatro. Altro campione di questo espediente stilistico, di questo testo breve ma ricchissimo di significato, fu Blaise Pascal, che nei Pensées, formidabile apologia del Cristianesimo nonché introspezione del rapporto tra l’uomo e il Divino, mise a nudo i punti cardini della miseria e della finitezza umana, sui quali Bernhard fece leva in maniera personalissima, per consolidare la propria visione del mondo e per dare vita alla teologia negativa che pervade le sue opere.

  11. On resolving the 180 deg ambiguity for a temporal sequence of vector magnetograms

    Science.gov (United States)

    Cheung, M. C.

    2008-05-01

    The solar coronal magnetic field evolves in response to the underlying photospheric driving. To study this connection by means of data-driven modeling, an accurate knowledge of the evolution of the photospheric vector field is essential. While there is a large body of work on attempts to resolve the 180 deg ambiguity in the component of the magnetic field transverse to the line of sight, most of these methods are applicable only to individual frames. With the imminent launch of the Solar Dynamics Observatory, it is especially timely for us to develop possible automated methods to resolve the ambiguity for temporal sequences of magnetograms. We present here the temporal acute angle method, which makes use of preceding disambiguated magnetograms as reference solutions for resolving the ambiguity in subsequent frames. To find the strengths and weaknesses of this method, we have carried out tests (1) on idealized magnetogram sequences involving simple rotating, shearing and straining flows and (2) on a synthetic magnetogram sequence from a 3D radiative MHD simulation of an buoyant magnetic flux tube emerging through granular convection. A metric for automatically picking out regions where the method is likely to fail is also presented.

  12. [Physical activity: results of the German Health Interview and Examination Survey for Adults (DEGS1)].

    Science.gov (United States)

    Krug, S; Jordan, S; Mensink, G B M; Müters, S; Finger, J; Lampert, T

    2013-05-01

    Regular physical activity can have a positive effect on health at any age. Today's lifestyles, however, can often be characterised as sedentary. Therefore, the promotion of physical activity and sports has become an integral part of public health measures. The representative data of adults aged 18 to 79 years in Germany obtained from the "German Health Interview and Examination Survey for Adults" (DEGS1) provide an overview of self-estimated current physical activity behaviour. The results show that one third of the adult population claims to pay close attention to reaching a sufficient level of physical activity and one fourth participates in sports for at least 2 h/week on a regular basis. Thus, the percentage of adults regularly engaged in sports has increased compared to the previous "German National Health Interview and Examination Survey 1998". Still, four out of five adults do not achieve at least 2.5 h/week of moderate-intensity physical activity as recommended by the World Health Organisation. Consequently, future individual-level and population-level interventions should focus on target group-specific measures while continuing to promote regular physical activity in all segments of the population. An English full-text version of this article is available at SpringerLink as supplemental.

  13. Bias-dependent timing jitter of 1-GHz sinusoidally gated InGaAs/InP avalanche photodiode

    Science.gov (United States)

    Zhu, Ge; Zheng, Fu; Wang, Chao; Sun, Zhibin; Zhai, Guangjie; Zhao, Qing

    2016-11-01

    We characterized the dependence of the timing jitter of an InGaAs/InP single-photon avalanche diode on the excess bias voltage (V ex) when operated in 1-GHz sinusoidally gated mode. The single-photon avalanche diode was cooled to -30 degrees Celsius. When the V ex is too low (0.2 V-0.8 V) or too high (3 V-4.2 V), the timing jitter is increased with the V ex, particularly at high V ex. While at middle V ex (1 V-2.8 V), the timing jitter is reduced. Measurements of the timing jitter of the same avalanche diode with pulsed gating show that this effect is likely related to the increase of both the amplitude of the V ex and the width of the gate-on time. For the 1-GHz sinusoidally gated detector, the best jitter of 93 ps is achieved with a photon detection efficiency of 21.4% and a dark count rate of ˜2.08×10-5 per gate at the V ex of 2.8 V. To evaluate the whole performance of the detector, we calculated the noise equivalent power (NEP) and the afterpulse probability (P ap). It is found that both NEP and P ap increase quickly when the V ex is above 2.8 V. At 2.8-V V ex, the NEP and P ap are ˜2.06×10-16 W/Hz1/2 and 7.11%, respectively. Therefore, the detector should be operated with V ex of 2.8 V to exploit the fast time response, low NEP and low P ap. Project supported by the National Natural Science Foundation of China (Grant Nos. 11275024, 61274024, and 61474123), the Youth Innovation Promotion Association, China (Grant No. 2013105), and the Ministry of Science and Technology of China (Grant Nos. 2013YQ030595-3 and 2011AA120101).

  14. Effects of corrosion and precipitates on mechanical properties in the ferritic/martensitic steel cladding under ultra-long cycle fast reactor environment at 650 .deg. C

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Tae Yong; Lee, Jeong Hyeon; Kim, Ji Hyun [UNIST, Ulsan (Korea, Republic of); Shin, Sang Hun [KAERI, Daejeon (Korea, Republic of)

    2016-05-15

    This changes chemical compositions of inter-surface and effects on behavior of precipitations. NaCrO{sub 2} which is ternary sodium compound occurs intergranular corrosion resulting in thickness reduction. This change can cause a degradation of mechanical strength of structure material of UCFR. Therefore, we should consider longterm compatibility with sodium and study about life prediction. The research about ferritic/martensitic steel on effects of long term exposure in liquid sodium at 650 .deg. C, 20ppm oxygen includes weight loss of test material (Gr. 92) by corrosion and mechanism about nucleation and growth of precipitates like Laves-phase in bulk. There are many changes such as segregation of component to nucleate precipitates, affecting into microstructural evolution of the steel. Therefore, the thermochemical reaction research to predict behavior about precipitates should be performed. In a specific procedure, the micro-structure and the surface phenomenon of ferritic/martensitic steels (Gr. 92) that are exposed to liquid sodium at 650 .deg. C, 20 ppm oxygen and aged in high pure Argon gas environment to express bulk have been investigated by using scanning electron microscope (SEM) and transmission electron microscope (TEM). At 10 ppm oxygen designed oxygen value for UCFR, there is 107μm thickness reduction for 30 years. Thus, if there is no degradation of mechanical strength caused by aging effect, the tolerance of load of initial cladding should be higher than real load at least 23.6 %. Compared to specimens exposed to Ar-gas environment, Specimen which solutions are leaded into sodium has degradation of strength by reduction of solution hardening.

  15. MODIS/COMBINED MCD12C1 Land Cover Type Yearly L3 Global 0.05Deg CMG

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — MODIS/Terra+Aqua Land Cover Type Yearly L3 Global 0.05Deg CMG The Land Cover Type Yearly Climate Modeling Grid (CMG) is a lower spatial resolution (0.05?) product,...

  16. De novo transcriptome sequencing analysis and comparison of differentially expressed genes (DEGs in Macrobrachium rosenbergii in China.

    Directory of Open Access Journals (Sweden)

    Hai Nguyen Thanh

    Full Text Available Giant freshwater prawn (GFP; Macrobrachium rosenbergii is an exotic species that was introduced into China in 1976 and thereafter it became a major species in freshwater aquaculture. However the gene discovery in this species has been limited to small-scale data collection in China. We used the next generation sequencing technology for the experiment; the transcriptome was sequenced of samples of hepatopancreas organ in individuals from 4 GFP groups (A1, A2, B1 and B2. De novo transcriptome sequencing generated 66,953 isogenes. Using BLASTX to search the Non-redundant (NR, Search Tool for the Retrieval of Interacting Genes (STRING, and Kyoto Encyclopedia of Genes and Genome (KEGG databases; 21,224 unigenes were annotated, 9,552 matched unigenes with the Gene Ontology (GO classification; 5,782 matched unigenes in 25 categories of Clusters of Orthologous Groups of proteins (COG and 20,859 unigenes were consequently assigned to 312 KEGG pathways. Between the A and B groups 147 differentially expressed genes (DEGs were identified; between the A1 and A2 groups 6,860 DEGs were identified and between the B1 and B2 groups 5,229 DEGs were identified. After enrichment, the A and B groups identified 38 DEGs, but none of them were significantly enriched. The A1 and A2 groups identified 21,856 DEGs in three main categories based on functional groups: biological process, cellular_component and molecular function and the KEGG pathway defined 2,459 genes had a KEGG Ortholog-ID (KO-ID and could be categorized into 251 pathways, of those, 9 pathways were significantly enriched. The B1 and B2 groups identified 5,940 DEGs in three main categories based on functional groups: biological process, cellular_component and molecular function, and the KEGG pathway defined 1,543 genes had a KO-ID and could be categorized into 240 pathways, of those, 2 pathways were significantly enriched. We investigated 99 queries (GO which related to growth of GFP in 4 groups. After

  17. De novo transcriptome sequencing analysis and comparison of differentially expressed genes (DEGs) in Macrobrachium rosenbergii in China.

    Science.gov (United States)

    Nguyen Thanh, Hai; Zhao, Liangjie; Liu, Qigen

    2014-01-01

    Giant freshwater prawn (GFP; Macrobrachium rosenbergii) is an exotic species that was introduced into China in 1976 and thereafter it became a major species in freshwater aquaculture. However the gene discovery in this species has been limited to small-scale data collection in China. We used the next generation sequencing technology for the experiment; the transcriptome was sequenced of samples of hepatopancreas organ in individuals from 4 GFP groups (A1, A2, B1 and B2). De novo transcriptome sequencing generated 66,953 isogenes. Using BLASTX to search the Non-redundant (NR), Search Tool for the Retrieval of Interacting Genes (STRING), and Kyoto Encyclopedia of Genes and Genome (KEGG) databases; 21,224 unigenes were annotated, 9,552 matched unigenes with the Gene Ontology (GO) classification; 5,782 matched unigenes in 25 categories of Clusters of Orthologous Groups of proteins (COG) and 20,859 unigenes were consequently assigned to 312 KEGG pathways. Between the A and B groups 147 differentially expressed genes (DEGs) were identified; between the A1 and A2 groups 6,860 DEGs were identified and between the B1 and B2 groups 5,229 DEGs were identified. After enrichment, the A and B groups identified 38 DEGs, but none of them were significantly enriched. The A1 and A2 groups identified 21,856 DEGs in three main categories based on functional groups: biological process, cellular_component and molecular function and the KEGG pathway defined 2,459 genes had a KEGG Ortholog-ID (KO-ID) and could be categorized into 251 pathways, of those, 9 pathways were significantly enriched. The B1 and B2 groups identified 5,940 DEGs in three main categories based on functional groups: biological process, cellular_component and molecular function, and the KEGG pathway defined 1,543 genes had a KO-ID and could be categorized into 240 pathways, of those, 2 pathways were significantly enriched. We investigated 99 queries (GO) which related to growth of GFP in 4 groups. After enrichment we

  18. Bacillus subtilis response regulator DegU is a direct activator of pgsB transcription involved in gamma-poly-glutamic acid synthesis.

    Science.gov (United States)

    Ohsawa, Taku; Tsukahara, Kensuke; Ogura, Mitsuo

    2009-09-01

    pgsB encodes gamma-poly glutamic acid (gamma-PGA) synthetase and constitutes an operon with pgsC, pgsAA, and pgsE. Genetic analysis revealed that degQ and swrA, the known regulators of pgsB, are not required for pgsB expression when high cellular concentrations of phosphorylated form of the response regulator DegU (DegU-P) are present. However, swrA appeared still to be required for gamma-PGA synthesis under the conditions we tested. Since genetic analysis suggested that DegU-P activates pgsB directly, we performed gel retardation and footprint analyses using purified His-tagged DegU and the pgsB promoter. The in vitro experiments revealed that His-tagged DegU bound to the immediate upstream region of the -35 region of the pgsB promoter. A six-base deletion within the sequence (the -44 to -39 region) abolished DegU-binding to the pgsB promoter and pgsB transcription, confirming the importance of the sequence for DegU-dependent regulation of pgsB. Hence we conclude that DegU is a direct activator of the pgsB operon.

  19. Proteomic approaches to identify substrates of the three Deg/HtrA proteases of the cyanobacterium Synechocystis sp. PCC 6803.

    Science.gov (United States)

    Tam, Lam X; Aigner, Harald; Timmerman, Evy; Gevaert, Kris; Funk, Christiane

    2015-06-15

    The family of Deg/HtrA proteases plays an important role in quality control of cellular proteins in a wide range of organisms. In the genome of the cyanobacterium Synechocystis sp. PCC 6803, a model organism for photosynthetic research and renewable energy products, three Deg proteases are encoded, termed HhoA, HhoB and HtrA. In the present study, we compared wild-type (WT) Synechocystis cells with the single insertion mutants ΔhhoA, ΔhhoB and ΔhtrA. Protein expression of the remaining Deg/HtrA proteases was strongly affected in the single insertion mutants. Detailed proteomic studies using DIGE (difference gel electrophoresis) and N-terminal COFRADIC (N-terminal combined fractional diagonal chromatography) revealed that inactivation of a single Deg protease has similar impact on the proteomes of the three mutants; differences to WT were observed in enzymes involved in the major metabolic pathways. Changes in the amount of phosphate permease system Pst-1 were observed only in the insertion mutant ΔhhoB. N-terminal COFRADIC analyses on cell lysates of ΔhhoB confirmed changed amounts of many cell envelope proteins, including the phosphate permease systems, compared with WT. In vitro COFRADIC studies were performed to identify the specificity profiles of the recombinant proteases rHhoA, rHhoB or rHtrA added to the Synechocystis WT proteome. The combined in vivo and in vitro N-terminal COFRADIC datasets propose RbcS as a natural substrate for HhoA, PsbO for HhoB and HtrA and Pbp8 for HtrA. We therefore suggest that each Synechocystis Deg protease protects the cell through different, but connected mechanisms. © The Authors Journal compilation © 2015 Biochemical Society.

  20. Free Fatty Acids Differentially Downregulate Chemokines in Liver Sinusoidal Endothelial Cells: Insights into Non-Alcoholic Fatty Liver Disease.

    Science.gov (United States)

    McMahan, Rachel H; Porsche, Cara E; Edwards, Michael G; Rosen, Hugo R

    2016-01-01

    Non-alcoholic fatty liver disease is a prevalent problem throughout the western world. Liver sinusoidal endothelial cells (LSEC) have been shown to play important roles in liver injury and repair, but their role in the underlying pathogenetic mechanisms of non-alcoholic fatty liver disease remains undefined. Here, we evaluated the effects of steatosis on LSEC gene expression in a murine model of non-alcoholic fatty liver disease and an immortalized LSEC line. Using microarray we identified distinct gene expression profiles following exposure to free fatty acids. Gene pathway analysis showed a number of differentially expressed genes including those involved in lipid metabolism and signaling and inflammation. Interestingly, in contrast to hepatocytes, fatty acids led to decreased expression of pro-inflammatory chemokines including CCL2 (MCP-1), CXCL10 and CXCL16 in both primary and LSEC cell lines. Chemokine downregulation translated into a significant inhibition of monocyte migration and LSECs isolated from steatotic livers demonstrated a similar shift towards an anti-inflammatory phenotype. Overall, these pathways may represent a compensatory mechanism to reverse the liver damage associated with non-alcoholic fatty liver disease.

  1. Free Fatty Acids Differentially Downregulate Chemokines in Liver Sinusoidal Endothelial Cells: Insights into Non-Alcoholic Fatty Liver Disease.

    Directory of Open Access Journals (Sweden)

    Rachel H McMahan

    Full Text Available Non-alcoholic fatty liver disease is a prevalent problem throughout the western world. Liver sinusoidal endothelial cells (LSEC have been shown to play important roles in liver injury and repair, but their role in the underlying pathogenetic mechanisms of non-alcoholic fatty liver disease remains undefined. Here, we evaluated the effects of steatosis on LSEC gene expression in a murine model of non-alcoholic fatty liver disease and an immortalized LSEC line. Using microarray we identified distinct gene expression profiles following exposure to free fatty acids. Gene pathway analysis showed a number of differentially expressed genes including those involved in lipid metabolism and signaling and inflammation. Interestingly, in contrast to hepatocytes, fatty acids led to decreased expression of pro-inflammatory chemokines including CCL2 (MCP-1, CXCL10 and CXCL16 in both primary and LSEC cell lines. Chemokine downregulation translated into a significant inhibition of monocyte migration and LSECs isolated from steatotic livers demonstrated a similar shift towards an anti-inflammatory phenotype. Overall, these pathways may represent a compensatory mechanism to reverse the liver damage associated with non-alcoholic fatty liver disease.

  2. Generation of equivalent forms of operational trans-conductance amplifier-RC sinusoidal oscillators: the nullor approach

    Directory of Open Access Journals (Sweden)

    Raj Senani

    2014-06-01

    Full Text Available It has been shown in two earlier papers published from this study that corresponding to a given single-operational trans-conductance amplifier (single-OTA-RC and dual-OTA-RC sinusoidal oscillators, there are three other structurally distinct equivalent forms having the same characteristic equation, one of which employs both grounded capacitors (GC. In this study, an earlier nullor-based theory of generating equivalent op-amp oscillator circuits, proposed by the first author, is extended to derive equivalent OTA-RC circuits which discloses the existence of an additional number of equivalent forms for the same given OTA-RC oscillators than those predicted by the quoted earlier works, and thereby considerably enlarging the set of equivalents of a given OTA-RC oscillator. Furthermore, the presented nullor-based theory of generating equivalent OTA-RC oscillators results in three additional interesting outcomes: (i the revelation that corresponding to any given OTA-RC oscillator there are two ‘both-GC’ oscillators (and not merely one, as derived in the quoted earlier works; (ii the availability of explicit current outputs in several of the derived equivalents and (iii the realisability explicit-current-output ‘quadrature oscillators’ in some of the generated equivalent oscillators. The workability of the generated equivalent OTA-RC oscillators has been verified by SPICE simulations, based on CMOS OTAs using 0.18 µm CMOS technology process parameters, and some sample results are given.

  3. Nonpulsed sinusoidal electromagnetic fields as a noninvasive strategy in bone repair: the effect on human mesenchymal stem cell osteogenic differentiation.

    Science.gov (United States)

    Ledda, Mario; D'Emilia, Enrico; Giuliani, Livio; Marchese, Rodolfo; Foletti, Alberto; Grimaldi, Settimio; Lisi, Antonella

    2015-02-01

    In vivo control of osteoblast differentiation is an important process needed to maintain the continuous supply of mature osteoblast cells for growth, repair, and remodeling of bones. The regulation of this process has also an important and significant impact on the clinical strategies and future applications of cell therapy. In this article, we studied the effect of nonpulsed sinusoidal electromagnetic field radiation tuned at calcium-ion cyclotron frequency of 50 Hz exposure treatment for bone differentiation of human mesenchymal stem cells (hMSCs) alone or in synergy with dexamethasone, their canonical chemical differentiation agent. Five days of continuous exposure to calcium-ion cyclotron resonance affect hMSC proliferation, morphology, and cytoskeletal actin reorganization. By quantitative real-time polymerase chain reaction, we also observed an increase of osteoblast differentiation marker expression such as Runx2, alkaline phosphatase (ALP), osteocalcin (OC), and osteopontin (OPN) together with the osteoprotegerin mRNA modulation. Moreover, in these cells, the increase of the protein expression of OPN and ALP was also demonstrated. These results demonstrate bone commitment of hMSCs through a noninvasive and biocompatible differentiating physical agent treatment and highlight possible applications in new regenerative medicine protocols.

  4. Automatic Frequency Identification under Sample Loss in Sinusoidal Pulse Width Modulation Signals Using an Iterative Autocorrelation Algorithm

    Directory of Open Access Journals (Sweden)

    Alejandro Said

    2016-08-01

    Full Text Available In this work, we present a simple algorithm to calculate automatically the Fourier spectrum of a Sinusoidal Pulse Width Modulation Signal (SPWM. Modulated voltage signals of this kind are used in industry by speed drives to vary the speed of alternating current motors while maintaining a smooth torque. Nevertheless, the SPWM technique produces undesired harmonics, which yield stator heating and power losses. By monitoring these signals without human interaction, it is possible to identify the harmonic content of SPWM signals in a fast and continuous manner. The algorithm is based in the autocorrelation function, commonly used in radar and voice signal processing. Taking advantage of the symmetry properties of the autocorrelation, the algorithm is capable of estimating half of the period of the fundamental frequency; thus, allowing one to estimate the necessary number of samples to produce an accurate Fourier spectrum. To deal with the loss of samples, i.e., the scan backlog, the algorithm iteratively acquires and trims the discrete sequence of samples until the required number of samples reaches a stable value. The simulation shows that the algorithm is not affected by either the magnitude of the switching pulses or the acquisition noise.

  5. Analysis and Adaptive Synchronization of Two Novel Chaotic Systems with Hyperbolic Sinusoidal and Cosinusoidal Nonlinearity and Unknown Parameters

    Directory of Open Access Journals (Sweden)

    S. Vaidyanathan

    2013-09-01

    Full Text Available This research work describes the modelling of two novel 3-D chaotic systems, the first with a hyperbolic sinusoidal nonlinearity and two quadratic nonlinearities (denoted as system (A and the second with a hyperbolic cosinusoidal nonlinearity and two quadratic nonlinearities (denoted as system (B. In this work, a detailed qualitative analysis of the novel chaotic systems (A and (B has been presented, and the Lyapunov exponents and Kaplan-Yorke dimension of these chaotic systems have been obtained. It is found that the maximal Lyapunov exponent (MLE for the novel chaotic systems (A and (B has a large value, viz. for the system (A and for the system (B. Thus, both the novel chaotic systems (A and (B display strong chaotic behaviour. This research work also discusses the problem of finding adaptive controllers for the global chaos synchronization of identical chaotic systems (A, identical chaotic systems (B and nonidentical chaotic systems (A and (B with unknown system parameters. The adaptive controllers for achieving global chaos synchronization of the novel chaotic systems (A and (B have been derived using adaptive control theory and Lyapunov stability theory. MATLAB simulations have been shown to illustrate the novel chaotic systems (A and (B, and also the adaptive synchronization results derived for the novel chaotic systems (A and (B.

  6. Adaptive filtering techniques for gravitational wave interferometric data Removing long-term sinusoidal disturbances and oscillatory transients

    CERN Document Server

    Chassande-Mottin, E

    2001-01-01

    It is known by the experience gained from the gravitational wave detector proto-types that the interferometric output signal will be corrupted by a significant amount of non-Gaussian noise, large part of it being essentially composed of long-term sinusoids with slowly varying envelope (such as violin resonances in the suspensions, or main power harmonics) and short-term ringdown noise (which may emanate from servo control systems, electronics in a non-linear state, etc.). Since non-Gaussian noise components make the detection and estimation of the gravitational wave signature more difficult, a denoising algorithm based on adaptive filtering techniques (LMS methods) is proposed to separate and extract them from the stationary and Gaussian background noise. The strength of the method is that it does not require any precise model on the observed data: the signals are distinguished on the basis of their autocorrelation time. We believe that the robustness and simplicity of this method make it useful for data prep...

  7. Response of the seated human body to whole-body vertical vibration: discomfort caused by sinusoidal vibration.

    Science.gov (United States)

    Zhou, Zhen; Griffin, Michael J

    2014-01-01

    Frequency weightings for predicting vibration discomfort assume the same frequency-dependence at all magnitudes of vibration, whereas biodynamic studies show that the frequency-dependence of the human body depends on the magnitude of vibration. This study investigated how the frequency-dependence of vibration discomfort depends on the acceleration and the force at the subject-seat interface. Using magnitude estimation, 20 males and 20 females judged their discomfort caused by sinusoidal vertical acceleration at 13 frequencies (1-16 Hz) at magnitudes from 0.1 to 4.0 ms(-2) r.m.s. The frequency-dependence of their equivalent comfort contours depended on the magnitude of vibration, but was less dependent on the magnitude of dynamic force than the magnitude of acceleration, consistent with the biodynamic non-linearity of the body causing some of the magnitude-dependence of equivalent comfort contours. There were significant associations between the biodynamic responses and subjective responses at all frequencies in the range 1-16 Hz. Practitioner Summary: Vertical seat vibration causes discomfort in many forms of transport. This study provides the frequency-dependence of vibration discomfort over a range of vibration magnitudes and shows how the frequency weightings in the current standards can be improved.

  8. Age and sex differences of controlled force exertion measured by a computer-generated sinusoidal target-pursuit system.

    Science.gov (United States)

    Nagasawa, Yoshinori; Demura, Shinichi

    2009-06-01

    This study examined age and sex differences of controlled force exertion in 207 males and 249 females aged 15 to 86 years. The subjects matched the submaximal grip strength of their dominant hand to changing demand values, appearing as a sinusoidal waveform on the display of a personal computer. The total difference (%) between the demand value and the grip exertion value for 25 sec was used as an evaluation parameter. Significant linear regressions were identified, but there was no significant difference in the rate of increase of both sexes. Analysis of variance showed insignificant differences among the means of both sexes, except for those of the 20-24yr-old group, and the differences between means of subjects greater than 50 years of age and 20 years of age increased in both sexes. Individual differences were almost the same in both sexes. The errors in controlled force exertion did not show a significant sex difference and tended to increase with age in both sexes. However, their rates of increase were significant only after 50 years of age.

  9. Multifunction Current Differencing Cascaded Transconductance Amplifier (MCDCTA) and Its Application to Current-Mode Multiphase Sinusoidal Oscillator

    Science.gov (United States)

    Wang, Chunhua; Lin, Hairong

    2015-09-01

    In this study, a new versatile active element, namely multifunction current differencing cascaded transconductance amplifier (MCDCTA), is proposed. This device which adopts a simple configuration enjoys the performances of low-voltage, low-input and high-output impedance, wide bandwidth etc. It simplifies the design of the current-mode analog signal processing circuit greatly, especially the design of high-order filter and oscillator circuits. Moreover, an example as a new current-mode multiphase sinusoidal oscillator (MSO) using MCDCTA is described in this paper. The proposed oscillator, which employs only one MCDCTA and minimum grounded passive elements, is easy to be realized. It can provide random n (n being odd or even) output current signals and these output currents are equally spaced in phase all at high output impedance terminals. Its oscillation condition and the oscillation frequency can be adjusted independently, linearly and electronically by controlling the bias currents of MCDCTA. The operation of the proposed oscillator has been testified through PSPICE simulation and experimental results.

  10. ICAM-1 Upregulation in Ethanol-Induced Fatty Murine Livers Promotes Injury and Sinusoidal Leukocyte Adherence after Transplantation

    Directory of Open Access Journals (Sweden)

    Tom P. Theruvath

    2012-01-01

    Full Text Available Background. Transplantation of ethanol-induced steatotic livers causes increased graft injury. We hypothesized that upregulation of hepatic ICAM-1 after ethanol produces increased leukocyte adherence, resulting in increased generation of reactive oxygen species (ROS and injury after liver transplantation (LT. Methods. C57BL/6 wildtype (WT and ICAM-1 knockout (KO mice were gavaged with ethanol (6 g/kg or water. LT was then performed into WT recipients. Necrosis and apoptosis, 4-hydroxynonenal (4-HNE immunostaining, and sinusoidal leukocyte movement by intravital microscopy were assessed. Results. Ethanol gavage of WT mice increased hepatic triglycerides 10-fold compared to water treatment (P<0.05. ICAM-1 also increased, but ALT was normal. At 8 h after LT of WT grafts, ALT increased 2-fold more with ethanol than water treatment (P<0.05. Compared to ethanol-treated WT grafts, ALT from ethanol-treated KO grafts was 78% less (P<0.05. Apoptosis also decreased by 75% (P<0.05, and 4-HNE staining after LT was also decreased in ethanol-treated KO grafts compared to WT. Intravital microscopy demonstrated a 2-fold decrease in leukocyte adhesion in KO grafts compared to WT grafts. Conclusions. Increased ICAM-1 expression in ethanol-treated fatty livers predisposes to leukocyte adherence after LT, which leads to a disturbed microcirculation, oxidative stress and graft injury.

  11. Investigation of the longitudinal magnetic field effect on dynamic response of viscoelastic graphene sheet based on sinusoidal shear deformation theory

    Science.gov (United States)

    Arani, A. Ghorbanpour; Jalaei, M. H.

    2017-02-01

    This research aims to investigate the influence of a longitudinal magnetic field on the dynamic response of single-layered graphene sheet (SLGS) resting on viscoelastic foundation based on the nonlocal sinusoidal shear deformation theory. The present model is capable of capturing both small scale effect and transverse shear deformation effects of nanoplate, and does not require shear correction factors. The material properties of graphene sheet are assumed orthotropic viscoelastic using Kelvin-Voigt model. Utilizing Hamilton's principle governing equations of motion are derived and solved analytically. The parametric study is conducted, focusing on the remarkable effects of the magnetic field, structural damping, stiffness and damping coefficient of the foundation, nonlocal parameter, aspect ratio and length to thickness ratio on the dynamic response of the SLGS. Results indicate that the longitudinal magnetic field exerted on the SLGS decreases the amplitude of dynamic response. In addition, it is observed that the magnetic field effect on the dynamic response is more distinguished as the nonlocal parameter increases while by increasing the foundation and structural damping coefficients, this effect diminishes. The results of this study can be used in design and manufacturing of nanomechanical devices in the presence of magnetic field as a parametric controller.

  12. Detecting non-sinusoidal periodicities in observational data: the von Mises periodogram for variable stars and exoplanetary transits

    CERN Document Server

    Baluev, Roman V

    2013-01-01

    This paper introduces an extension of the linear least-squares (or Lomb-Scargle) periodogram for the case when the model of the signal to be detected is non-sinusoidal and depends on unknown parameters in a non-linear manner. The attention is paid to the problem of estimating the statistical significance of candidate periodicities found using such non-linear periodograms. This problem is related to the task of quantifying the distributions of maximum values of these periodograms. Based on recent results in the mathematical theory of extreme values of random field (the generalized Rice method), we give a general approach to find handy analytic approximation for these distributions. This approximation has the general form $e^{-z} P(\\sqrt z)$, where $P$ is an algebraic polynomial and $z$ being the periodogram maximum. The general tools developed in this paper can be used in a wide variety of astronomical applications, for instance in the studies of variable stars and extrasolar planets. For this goal, we develop...

  13. Effects of lead on ultrastructural charactristics of sinusoidal endothelial cell of fetal rat's spleen

    Directory of Open Access Journals (Sweden)

    Heydari Z

    1997-08-01

    Full Text Available Amount of environmental lead pollution is increased with progression of industry. This pollution is able to damage the living beings in many ways. Blood and Immune systems are more sensitive to toxic effects of lead. 30 female and 6 male rats from Sprague dawley race are chosen by simple random sampling. After copulation and vaginal plug observation, expectant rats are calssified in test and control groups. Since the first day of pregnancy, test group is given a drink containing lead acetate 0.13% in distilled water and control group is given distilled water. After delivery, for ultrastrectural studies, spleen specimens of newborn rats are fixed in glutaraldehyde solution 2% and after processing are studied by T.E.M. Sinusoidal endothelial cell show: morphological changes in mitochondria, appearance of primary & secondary lysosomes and multivesicular bodies and swelling in ER. It seems that these changes are caused by interaction of lead with enzymathic functions or lead accumulation in these cellular organels.

  14. Approach for discrimination and quantification of electroactive species: kinetics difference revealed by higher harmonics of Fourier transformed sinusoidal voltammetry.

    Science.gov (United States)

    Fang, Yishan; Huang, Xinjian; Wang, Lishi

    2015-01-06

    Discrimination and quantification of electroactive species are traditionally realized by a potential difference which is mainly determined by thermodynamics. However, the resolution of this approach is limited to tens of millivolts. In this paper, we described an application of Fourier transformed sinusoidal voltammetry (FT-SV) that provides a new approach for discrimination and quantitative evaluation of electroactive species, especially thermodynamic similar ones. Numerical simulation indicates that electron transfer kinetics difference between electroactive species can be revealed by the phase angle of higher order harmonics of FT-SV, and the difference can be amplified order by order. Thus, even a very subtle kinetics difference can be amplified to be distinguishable at a certain order of harmonics. This method was verified with structurally similar ferrocene derivatives which were chosen as the model systems. Although these molecules have very close redox potential (<10 mV), discrimination and selective detection were achieved by as high as the thirteenth harmonics. The results demonstrated the feasibility and reliability of the method. It was also implied that the combination of the traditional thermodynamic method and this kinetics method can form a two-dimension resolved detection method, and it has the potential to extend the resolution of voltammetric techniques to a new level.

  15. Effects of sinusoidal endothelial cell conditioned medium on the expressionof connective tissue growth factor in rat hepatic stellate cells

    Institute of Scientific and Technical Information of China (English)

    Xiao Jing Liu; Fang Liu; Wen Jun Xiao; Ming Hui Huang; Song Min Huang; Yi Ping Wang

    2000-01-01

    AIM To investigate the effects of sinusoidal endothelial cell (SEC) conditioned medium on the expression ofconnective tissue growth factor (CTGF) in rat hepatic stellate cells (HSC).METHODS By in situ collagenase perfusion and two-step Percoll gradient centrifugation, SECs wereisolated and cultured from normally and CCl4-treated Wistar rats, and the SEC conditioned media werecollected. HSCs were prepared from Wistar rats by in situ perfusion and single-step Nycodenz gradient, andwere cultured with SEC conditioned media. Expression of CTGF in HSC was assessed using reversetranscription-polymerase chain reaction (RT-PCR).RESULTS Expression of CTGF was not found in freshly isolated HSC and in primary culture of HSC onday 4 with SEC conditioned media from normal rats, but was present in primary culture of HSC on day 4 withSEC conditioned media from CCl4-induced liver fibrosis rats. Expression of CTGF was observed in culture-activated HSCs, and the effect of SEC conditioned media from CCl4-induced liver fibrosis rats on theexpression of CTGF gene in activated HSCs was not significant.CONCLUSION Expression of CTGF might be relative to the activation of HSC and the liver fibrogenesis,and damaged SECs play a very important role in the early stage of activation of HSC.

  16. Investigation of the longitudinal magnetic field effect on dynamic response of viscoelastic graphene sheet based on sinusoidal shear deformation theory

    Energy Technology Data Exchange (ETDEWEB)

    Arani, A. Ghorbanpour, E-mail: aghorban@kashanu.ac.ir [Faculty of Mechanical Engineering, University of Kashan, Kashan (Iran, Islamic Republic of); Institute of Nanoscience & Nanotechnology University of Kashan, Kashan (Iran, Islamic Republic of); Jalaei, M.H. [Faculty of Mechanical Engineering, University of Kashan, Kashan (Iran, Islamic Republic of)

    2017-02-01

    This research aims to investigate the influence of a longitudinal magnetic field on the dynamic response of single-layered graphene sheet (SLGS) resting on viscoelastic foundation based on the nonlocal sinusoidal shear deformation theory. The present model is capable of capturing both small scale effect and transverse shear deformation effects of nanoplate, and does not require shear correction factors. The material properties of graphene sheet are assumed orthotropic viscoelastic using Kelvin-Voigt model. Utilizing Hamilton's principle governing equations of motion are derived and solved analytically. The parametric study is conducted, focusing on the remarkable effects of the magnetic field, structural damping, stiffness and damping coefficient of the foundation, nonlocal parameter, aspect ratio and length to thickness ratio on the dynamic response of the SLGS. Results indicate that the longitudinal magnetic field exerted on the SLGS decreases the amplitude of dynamic response. In addition, it is observed that the magnetic field effect on the dynamic response is more distinguished as the nonlocal parameter increases while by increasing the foundation and structural damping coefficients, this effect diminishes. The results of this study can be used in design and manufacturing of nanomechanical devices in the presence of magnetic field as a parametric controller.

  17. Capillary effect on the sloshing of a fluid in a rectangular tank submitted to sinusoidal vertical dynamical excitation

    Institute of Scientific and Technical Information of China (English)

    MEZIANI Bachir; OURRAD Ouerdia

    2014-01-01

    Surface tension effects on fluid sloshing in a tank subjected to external excitation has been less studied. This work aims at understanding this phenomenon in order to derive practical solutions to problems faced in several engineering. A tank containing a fluid with a free surface is submitted to gravity and capillary forces and subject to external dynamic excitation. Introduction of vertical sinusoidal dynamical excitation leads to a problem of paramtric oscillations governed by the Mathieu equation. Analysis of the Mathieu equation shows the existence of stable and unstable regions in the stability diagram. Some results induced by harmonic excitations on the fluid sloshing are presented. When the external dynamical excitation amplitude e is small, periodic solutions appear in stable regions and when e increases, the fluid behavior is not perfectly periodic and the amplitudes are not regular. Nonlinear effects make the behavior of the fluid complicated and render it almost unpredictable. In stable regions, the solution remains bounded at any time. When changing the perturbation parameter e, the phase difference increases and also with the increase of the surface tension.

  18. Experimental wake survey behind Viking 75 entry vehicle at angles of attack of 0 deg, 5 deg, and 10 deg, Mach numbers from 0.20 to 1.20, and longitudinal stations from 1.50 to 11.00 body diameters

    Science.gov (United States)

    Brown, C. A., Jr.; Campbell, J. F.

    1973-01-01

    An investigation was conducted to obtain flow properties in the wake of a preliminary configuration of the Viking '75 Entry Vehicle at Mach numbers from 0.20 to 1.20 and at angles of attack of 0 deg, 5 deg, and 10 deg. The wake flow properties were calculated from total and static pressures measured with a pressure rake at longitudinal stations varying from 1.50 to 11.00 body diameters, and are presented in tabulated and plotted form. The wake properties were essentially symmetrical about the X-axis at alpha = 0 deg and the profiles were shifted away from the X-axis at angles of attack. An unexpected reduction in wake property ratios occurred as the Mach number increased from 0.60 to 1.00; these ratios then increased as the Mach number increased to 1.20. The reduction was present for all the longitudinal stations of the tests and decreased with increased longitudinal distance.

  19. Letteratura tecnica e formazione degli architetti ai tempi di Antonio Mollari

    Directory of Open Access Journals (Sweden)

    Alessandro Gambuti

    2014-04-01

    Full Text Available Nel corso del Settecento, nella letteratura tecnica, a seguito della critica razionalista del pensiero illuminista, cominciano a comparire principî scientifici per migliorare la formazione degli architetti. Nel 1764 Girolamo Fonda, matematico, pubblica gli Elementi di Architettura civile e militare e dedica la prima parte alla “Sodezza delle fabbriche”, premettendo le regole costruttive alla convenienza e all’estetica. Francesco Milizia avvia i Principj di Architettura civile (1781 con i temi della bellezza e della comodità, ma, nella terza parte, tratta della solidità con citazioni di meccanica, fisica e ingegneria. Qualche anno dopo (1788, Girolamo Masi stampa, per la “gioventù romana”, Teoria e Pratica dell’Architettura civile; seguendo il metodo del Fonda e continuando l’opera del Milizia egli propone nozioni sui materiali e sulle “resistenze” con il sussidio di illustrazioni e tabelle. Nel 1772 era stato ristampato il Manuale… di Giovanni Branca con la revisione di Leonardo de Vegni, dilettante di architettura; una notevole utilità didattica apportarono le incisioni di Giovan Battista Cipriani, allegate ai Principj… del Milizia (1800 e le Osservazioni ed aggiunte di Giovanni Antonio Antolini alla stessa opera (1817. All’inizio dell’Ottocento, l’Architettura pratica di Giuseppe Valadier dette un incremento alla formazione professionale degli architetti per mezzo di lezioni teoriche e disegni di procedimenti ed attrezzature per i costruttori di edifici. During the XVIIIth century, in the technical treatises, owing to the rationalist criticism of the Enlightenment movement, scientific principles begin to appear in order to improve the education of the architects. In 1764 Girolamo Fonda, a mathematician, publishes Elementi di Architettura civile e militare and gives up the first part to the “Solidity of Buildings”, putting before the construction rules to the convenience and beauty. Francesco Milizia opens

  20. Criteri di indagine degli spazi voltati nell’ambito dell’architettura storica e in archeologia

    Directory of Open Access Journals (Sweden)

    Luca Cipriani

    2014-07-01

    Full Text Available ItLo studio degli spazi voltati nell’ambito dell’architettura storica è un tema di grande interesse, che da sempre vede impegnati vari studiosi afferenti ad ambiti disciplinari diversi, dall’archeologia, alla storia dell’arte, alla conservazione. In tale contesto interdisciplinare molto spesso il ruolo di ingegneri ed architetti, che si occupano di indagare le matrici geometriche alla base della progettazione di tali spazi, viene relegato ad un ruolo accessorio rispetto a quello dei conservatori, che materialmente si occupano delle pratiche di manutenzione e di restauro. Con l’avanzare delle tecnologie di rilevamento, che spaziano con sempre maggiore affidabilità dalla documentazione dei caratteri morfologici superficiali a quelli più intrinseci alla base dei manufatti, quale può essere il ruolo attuale di chi si occupa di comprendere il progetto che generò tali ambienti? In altri termini, quel vasto patrimonio immateriale che sta alla base della concezione progettuale di un manufatto, specialmente se scaturito da una raffinata conoscenza matematica e geometrica, ha oggi un ruolo riconoscibile e sufficientemente autorevole rispetto all’ammontare di conoscenze tecniche che permettono alle “macchine” di funzionare?Con questo contributo si intende mostrare come l’integrazione di vari know-how legati sia alla modellazione reality-based che alla conoscenza dei criteri e degli strumenti di progettazione del passato, possa fornire un input sostanziale per l’intervento e per la conoscenza di manufatti caratterizzati da una evidente complessità geometrica e costruttiva. Per ricaduta si intende poi mostrare come la documentazione fine a se stessa, per quanto accurata, certificata e garantita attraverso le più avanzate tecnologie e metodologie integrate, non si configuri come base di scambio e di dialogo interdisciplinare. En The study of vaulted spaces in the context of the historic architecture is a topic of great interest