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Sample records for residual doppler width

  1. Doppler-width thermodynamic thermometry by means of line-absorbance analysis

    Energy Technology Data Exchange (ETDEWEB)

    Castrillo, A.; De Vizia, M. D.; Gianfrani, L. [Dipartimento di Scienze Ambientali, Seconda Universita di Napoli, Caserta (Italy); Moretti, L. [Dipartimento di Matematica, Seconda Universita di Napoli, Caserta (Italy); Galzerano, G.; Laporta, P. [Dipartimento di Fisica, Politecnico di Milano and Istituto di Fotonica e Nanotecnologie (IFN-CNR), Milano (Italy); Merlone, A. [Istituto Nazionale di Ricerca Metrologica, Torino (Italy)

    2011-09-15

    A clean and effective implementation of Doppler-width thermometry is described. Exploiting the relationship between line-center absorbance and integrated absorbance, the Doppler width of a molecular spectral line can be retrieved from a set of profiles resulting from different gas pressures. The method is validated by its application to numerically simulated spectra. Preliminary experiments, in water vapor samples, turn out to be successful, demonstrating Doppler-widths' retrieval in the near-infrared with a precision of 8x10{sup -5}, at the water triple point temperature. The direct link to the Boltzmann constant makes the proposed method very attractive for temperature metrology as a tool for the realization of a new thermodynamic temperature scale.

  2. The diagnostic technique of doppler width for low-yield neutrons

    International Nuclear Information System (INIS)

    Chen Jiabin; Teng Hao; Feng Jie; Zheng Zhijian; Tang Daoyuan; Liu Zhongli

    1997-01-01

    The author introduces the diagnostic technique of Doppler Width for low-yield neutrons by ultra-fast-quenched plastic scintillation detector. The relation between measurement error and detector position has been calculated. The result shows that the diagnostic method and detector can be used for as low as 10 7 ∼10 8 neutron yield and 2∼3 KeV ion temperature

  3. Statistical characteristics of Doppler spectral width as observed by the conjugate SuperDARN radars

    Directory of Open Access Journals (Sweden)

    K. Hosokawa

    Full Text Available We performed a statistical analysis of the occurrence distribution of Doppler spectral width around the day-side high-latitude ionosphere using data from the conjugate radar pair composed of the CUTLASS Iceland-East radar in the Northern Hemisphere and the SENSU Syowa-East radar in the Southern Hemisphere. Three types of spectral width distribution were identified: (1 an exponential-like distribution in the lower magnetic latitudes (below 72°, (2 a Gaussian-like distribution around a few degrees magnetic latitude, centered on 78°, and (3 another type of distribution in the higher magnetic latitudes (above 80°. The first two are considered to represent the geophysical regimes such as the LLBL and the cusp, respectively, because they are similar to the spectral width distributions within the LLBL and the cusp, as classified by Baker et al. (1995. The distribution found above 80° magnetic latitude has been clarified for the first time in this study. This distribution has similarities to the exponential-like distribution in the lower latitude part, although clear differences also exist in their characteristics. These three spectral width distributions are commonly identified in conjugate hemispheres. The latitudinal transition from one distribution to another exhibits basically the same trend between two hemispheres. There is, however, an interhemispheric difference in the form of the distribution around the cusp latitudes, such that spectral width values obtained from Syowa-East are larger than those from Iceland-East. On the basis of the spectral width characteristics, the average locations of the cusp and the open/closed field line boundary are estimated statistically.

    Key words. Ionosphere (ionosphere-magnetosphere inter-actions; plasma convection – Magnetospheric physics (magnetopause, cusp, and boundary layers

  4. A Statistical study of the Doppler spectral width of high-latitude ionospheric F-region echoes recorded with SuperDARN coherent HF radars

    Directory of Open Access Journals (Sweden)

    J.-P. Villain

    Full Text Available The HF radars of the Super Dual Auroral Radar Network (SuperDARN provide measurements of the E × B drift of ionospheric plasma over extended regions of the high-latitude ionosphere. We have conducted a statistical study of the associated Doppler spectral width of ionospheric F-region echoes. The study has been conducted with all available radars from the Northern Hemisphere for 2 specific periods of time. Period 1 corresponds to the winter months of 1994, while period 2 covers October 1996 to March 1997. The distributions of data points and average spectral width are presented as a function of Magnetic Latitude and Magnetic Local Time. The databases are very consistent and exhibit the same features. The most stringent features are: a region of very high spectral width, collocated with the ionospheric LLBL/cusp/mantle region; an oval shaped region of high spectral width, whose equator-ward boundary matches the poleward limit of the Holzworth and Meng auroral oval. A simulation has been conducted to evaluate the geometrical and instrumental effects on the spectral width. It shows that these effects cannot account for the observed spectral features. It is then concluded that these specific spectral width characteristics are the signature of ionospheric/magnetospheric coupling phenomena.

    Key words. Ionosphere (auroral ionosphere; ionosphere-magnetosphere interactions; ionospheric irregularities

  5. A Statistical study of the Doppler spectral width of high-latitude ionospheric F-region echoes recorded with SuperDARN coherent HF radars

    Directory of Open Access Journals (Sweden)

    J.-P. Villain

    2002-11-01

    Full Text Available The HF radars of the Super Dual Auroral Radar Network (SuperDARN provide measurements of the E × B drift of ionospheric plasma over extended regions of the high-latitude ionosphere. We have conducted a statistical study of the associated Doppler spectral width of ionospheric F-region echoes. The study has been conducted with all available radars from the Northern Hemisphere for 2 specific periods of time. Period 1 corresponds to the winter months of 1994, while period 2 covers October 1996 to March 1997. The distributions of data points and average spectral width are presented as a function of Magnetic Latitude and Magnetic Local Time. The databases are very consistent and exhibit the same features. The most stringent features are: a region of very high spectral width, collocated with the ionospheric LLBL/cusp/mantle region; an oval shaped region of high spectral width, whose equator-ward boundary matches the poleward limit of the Holzworth and Meng auroral oval. A simulation has been conducted to evaluate the geometrical and instrumental effects on the spectral width. It shows that these effects cannot account for the observed spectral features. It is then concluded that these specific spectral width characteristics are the signature of ionospheric/magnetospheric coupling phenomena.Key words. Ionosphere (auroral ionosphere; ionosphere-magnetosphere interactions; ionospheric irregularities

  6. Residual-interaction renormalization effect on the spherical-nuclei α-decay absolute widths

    International Nuclear Information System (INIS)

    Dumitresku, T.; Kadmenskij, S.G.; Lomachenkov, I.A.; Kholan, S.; Furman, V.I.

    1978-01-01

    In the framework of the shell model approximation for the probabilities of alpha-decay the exact formulas (for alpha-widths) taking into account the contribution of density dependent effective interaction between nucleons forming the emitted alpha-particle are obtained. In agreement with previous estimations the numerical calculation reveals that the inclusion of the above-mentioned interaction is followed by some decrease of absolute alpha-widths

  7. Visible Spectrometer at the Compact Toroid Injection Experiment, the Sustained Spheromak Plasma Experiment and the Alcator C-Mod Tokamak for Doppler Width and Shift Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Graf, A; Howard, S; Horton, R; Hwang, D; May, M; Beiersdorfer, P; McLean, H; Terry, J

    2006-05-15

    A novel Doppler spectrometer is currently being used for ion or neutral velocity and temperature measurements on the Alcator C-Mod Tokamak. The spectrometer has an f/No. of {approx}3.1 and is appropriate for visible light (3500-6700 {angstrom}). The full width at half maximum from a line emitting calibration source has been measured to be as small as 0.4 {angstrom}. The ultimate time resolution is line brightness light limited and on the order of ms. A new photon efficient detector is being used for the setup at C-Mod. Time resolution is achieved by moving the camera during a plasma discharge in a perpendicular direction through the dispersion plane of the spectrometer causing a vertical streaking across the camera face. Initial results from C-Mod as well as previous measurements from the Compact Toroid Injection Experiment (CTIX) and the Sustained Spheromak Plasma Experiment (SSPX) are presented.

  8. Characteristics of the Residual Stress tensor when filter width is larger than the Ozmidov scale

    Science.gov (United States)

    de Bragança Alves, Felipe Augusto; de Bruyn Kops, Stephen

    2017-11-01

    In stratified turbulence, the residual stress tensor is statistically anisotropic unless the smallest resolved length scale is smaller than the Ozmidov scale and the buoyancy Reynolds number is sufficiently high for there to exist a range of scales that is statistically isotropic. We present approximations to the residual stress tensor that are derived analytically. These approximations are evaluated by filtering data from direct numerical simulations of homogeneous stratified turbulence, with unity Prandtl number, resolved on up to 8192 × 8192 × 4096 grid points along with an isotropic homogeneous case resolved on 81923 grid points. It is found that the best possible scaling of the strain rate tensor yields a residual stress tensor (RST) that is less well statistically aligned with the exact RST than a randomly generated tensor. It is also found that, while a scaling of the strain rate tensor can dissipate the right amount of energy, it produces incorrect anisotropic dissipation, removing energy from the wrong components of the velocity vector. We find that a combination of the strain rate tensor and a tensor related to energy redistribution caused by a Newtonian fluid viscous stress yields an excellent tensorial basis for modelling the RST.

  9. Evaluation of residual hepatocellular carcinoma after transcatheter arterial chemoembolization: Comparison between contrast-enhanced helical CT and contrast-enhanced power doppler ultrasonography

    International Nuclear Information System (INIS)

    Kim, Seung Hoon; Lim, Hyo Keun; Lee, Won Jae

    2001-01-01

    To evaluate the effectiveness of contrast-enhanced helical CT and contrast-enhanced power doppler ultrasonography (PDUS) in assessing the therapeutic effect of transcatheter arterial chemoembolization (TACE) in hepatocellular carcinomas (HCCs). The follow-up contrast-enhanced helical CT and contrast-enhanced PDUS were performed for twenty-nine nodular HCCs from twelve patients previously treated with TACE. We defined the residual HCCs as intratumoral enhancing area on contrast-enhanced helical CT and color signal on contrast-enhanced PDUS. The interval between two examinations was less than 2 weeks (mean, 9 days). Two radiologists evaluated two examinations by consensus, and the results of these two examination were compared with the findings of other examinations including CT, angiography, and/or pathology to calculate the sensitivity, specificity and accuracy of two examinations. Of the 29 HCCs, 20 had residual HCCs whereas no residual HCCs in 9 HCCs on pathologic examination and/or follow-up radiologic study. The sensitivity, sensitivity and accuracy of contrast-enhanced helical CT were 65 (13/20), 89 (8/9), and 72% (21/29) while those of contrast-enhanced PDUS were 100 (20/20), 89 (8/9) and 97% (28/29), respectively. A microbubble contrast-enhanced PDUS was more effective in the detection of residual tumor in HCCs following TACE than contrast-enhanced helical CT.

  10. Doppler ion program description

    International Nuclear Information System (INIS)

    Henline, P.

    1980-12-01

    The Doppler spectrometer is a conventional Czerny-Turner grating spectrometer with a 1024 channel multiple detector. Light is dispersed across the detector, and its output yields a spectrum covering approximately 200 A. The width of the spectral peak is directly proportional to the temperature of the emitting ions, and determination of the impurity ion temperature allows one to infer the plasma ion temperature. The Doppler ion software system developed at General Atomic uses a TRACOR Northern 1710-31 and an LSI-11/2. The exact configuration of Doublet III is different from TRACOR Northern systems at other facilities

  11. Doppler Tomography

    Science.gov (United States)

    Marsh, T. R.

    I review the method of Doppler tomography which translates binary-star line profiles taken at a series of orbital phases into a distribution of emission over the binary. I begin with a discussion of the basic principles behind Doppler tomography, including a comparison of the relative merits of maximum entropy regularisation versus filtered back-projection for implementing the inversion. Following this I discuss the issue of noise in Doppler images and possible methods for coping with it. Then I move on to look at the results of Doppler Tomography applied to cataclysmic variable stars. Outstanding successes to date are the discovery of two-arm spiral shocks in cataclysmic variable accretion discs and the probing of the stream/magnetospheric interaction in magnetic cataclysmic variable stars. Doppler tomography has also told us much about the stream/disc interaction in non-magnetic systems and the irradiation of the secondary star in all systems. The latter indirectly reveals such effects as shadowing by the accretion disc or stream. I discuss all of these and finish with some musings on possible future directions for the method. At the end I include a tabulation of Doppler maps published in refereed journals.

  12. Doppler lidar results from the San Gorgonio Pass experiments

    Science.gov (United States)

    Cliff, W. C.; Skarda, J. R.; Renne, D. S.

    1984-01-01

    During FY-84, the Doppler Lidar data from the San Gorgonio Pass experiments were analyzed, evaluated, and interpreted with regard to signal strength, signal width, magnitude and direction of velocity component and a goodness parameter associated with the expected noise level of the signal. From these parameters, a screening criteria was developed to eliminate questionable data. For the most part analysis supports the validity of Doppler Lidar data obtained at San Gorgonio Pass with respect to the mean velocity magnitude and direction. The question as to whether the Doppler width could be interpreted as a measure of the variance of the turbulence within the Doppler Lidar System (DLS) focal volume was not resolved. The stochastic nature of the Doppler broadening from finite residence time of the particles in the beam as well as other Doppler broadening phenomenon tend to mask the Doppler spread associated with small scale turbulence. Future tests with longer pulses may assist in better understanding.

  13. Doppler-free Fourier transform spectroscopy.

    Science.gov (United States)

    Meek, Samuel A; Hipke, Arthur; Guelachvili, Guy; Hänsch, Theodor W; Picqué, Nathalie

    2018-01-01

    Sub-Doppler broadband multi-heterodyne spectroscopy is proposed and experimentally demonstrated. Using two laser frequency combs of slightly different repetition frequencies, we have recorded Doppler-free two-photon dual-comb spectra of atomic rubidium resonances of a width of 6 MHz, while simultaneously interrogating a spectral span of 10 THz. The atomic transitions are uniquely identified via the intensity modulation of the observed fluorescence radiation. To the best of our knowledge, these results represent the first demonstration of Doppler-free Fourier transform spectroscopy and extend the range of applications of broadband spectroscopy towards precision nonlinear spectroscopy.

  14. The doppler ultrasound. La ecografia Doppler

    Energy Technology Data Exchange (ETDEWEB)

    Contreras Cecilia, E.; Lozano Setien, E.; Hernandez Montero, J.; Ganado Diaz, T.; Jorquera Moya, M.; Blasco Pascual, E. (Hospital Universitario San Carlos. Madrid (Spain))

    1994-01-01

    The discovery and development of Doppler ultrasound has had a great influence on Medical practice since it allows the noninvasive study of vascular pathology, both arterial and venous, as well as the flow patterns of the different parenchyma. This article deals with the principles, limitations and interpretation of the Doppler signal, as well as the different Doppler ultrasound systems routinely employed in Medicine.

  15. The effect of scattering interference term on the practical width

    International Nuclear Information System (INIS)

    Martins do Amaral, C.; Martinez, A.S.

    2001-01-01

    The practical width Γ p has an important application in the characterization of the resonance type for the calculation of neutron average cross sections. Previous treatments ignore the interference term χζ,x for the Doppler broadening function in the practical width calculation. In the present paper, a rational approximation for the χζ,x function is derived, using a modified asymptotic Pade method. A new approximation for Γ p is obtained. The results which are presented here provide evidence that the practical width as a function of temperature varies considerably with the inclusion of the interference term χζ,x

  16. Wide Angle Michelson Doppler Imaging Interferometer (WAMDII)

    Science.gov (United States)

    Roberts, B.

    1986-01-01

    The wide angle Michelson Doppler imaging interferometer (WAMDII) is a specialized type of optical Michelson interferometer working at sufficiently long path difference to measure Doppler shifts and to infer Doppler line widths of naturally occurring upper atmospheric Gaussian line emissions. The instrument is intended to measure vertical profiles of atmospheric winds and temperatures within the altitude range of 85 km to 300 km. The WAMDII consists of a Michelson interferometer followed by a camera lens and an 85 x 106 charge coupled device photodiode array. Narrow band filters in a filter wheel are used to isolate individual line emissions and the lens forms an image of the emitting region on the charge coupled device array.

  17. Pulse-width discriminators

    International Nuclear Information System (INIS)

    Budyashov, Yu.G.; Grebenyuk, V.M.; Zinov, V.G.

    1978-01-01

    A pulse duration discriminator is described which is intended for processing signals from multilayer scintillators. The basic elements of the scintillator are: an input gate, a current generator, an integrating capacitor, a Schmidt trigger and an anticoincidence circuit. The basic circuit of the discriminator and its time diagrams explaining its operating are given. The discriminator is based on microcircuits. Pulse duration discrimination threshold changes continuously from 20 to 100 ns, while its amplitude threshold changes within 20 to 100 mV. The temperature instability of discrimination thresholds (both in pulse width and in amplitude) is better than 0.1 per cent/deg C

  18. Width and partial widths of unstable particles in the light of the Nielsen identities

    International Nuclear Information System (INIS)

    Grassi, P.A.; Sirlin, A.; Kniehl, B.A.; Hamburg Univ.

    2001-09-01

    Fundamental properties of unstable particles, including mass, width, and partial widths, are examined on the basis of the Nielsen identities (NI) that describe the gauge dependence of Green functions. In particular, we prove that the pole residues and associated definitions of branching ratios and partial widths are gauge independent to all orders. A simpler, previously discussed definition of branching ratios and partial widths is found to be gauge independent through next-to-next-to-leading order. It is then explained how it may be modified in order to extend the gauge independence to all orders. We also show that the physical scattering amplitude is the most general combination of self-energy, vertex, and box contributions that is gauge independent for arbitrary s, discuss the analytical properties of the NI functions, and exhibit explicitly their one-loop expressions in the Z-γ sector of the Standard Model. (orig.)

  19. Sub-Doppler spectroscopy

    International Nuclear Information System (INIS)

    Hansch, T.W.

    1983-01-01

    This chapter examines Doppler-free saturation spectroscopy, tunable cw sources, and Doppler-free two-photon spectroscopy. Discusses saturation spectroscopy; continuous wave saturation spectroscopy in the ultraviolet; and two-photon spectroscopy of atomic hydrogen 1S-2S. Focuses on Doppler-free laser spectroscopy of gaseous samples. Explains that in saturation spectroscopy, a monochromatic laser beam ''labels'' a group of atoms within a narrow range of axial velocities through excitation or optical pumping, and a Doppler-free spectrum of these selected atoms is observed with a second, counterpropagating beam. Notes that in two-photon spectroscopy it is possible to record Doppler-free spectra without any need for velocity selection by excitation with two counterpropagating laser beams whose first order Doppler shifts cancel

  20. Advances in Doppler OCT

    Science.gov (United States)

    Liu, Gangjun; Chen, Zhongping

    2014-01-01

    We review the principle and some recent applications of Doppler optical coherence tomography (OCT). The advances of the phase-resolved Doppler OCT method are described. Functional OCT algorithms which are based on an extension of the phase-resolved scheme are also introduced. Recent applications of Doppler OCT for quantification of flow, imaging of microvasculature and vocal fold vibration, and optical coherence elastography are briefly discussed. PMID:24443649

  1. Doppler ultrasound exam of an arm or leg

    Science.gov (United States)

    Peripheral vascular disease - Doppler; PVD - Doppler; PAD - Doppler; Blockage of leg arteries - Doppler; Intermittent claudication - Doppler; Arterial insufficiency of the legs - Doppler; Leg pain and ...

  2. Ultrasonic colour Doppler imaging

    DEFF Research Database (Denmark)

    Evans, David H.; Jensen, Jørgen Arendt; Nielsen, Michael Bachmann

    2011-01-01

    Ultrasonic colour Doppler is an imaging technique that combines anatomical information derived using ultrasonic pulse-echo techniques with velocity information derived using ultrasonic Doppler techniques to generate colour-coded maps of tissue velocity superimposed on grey-scale images of tissue...... anatomy. The most common use of the technique is to image the movement of blood through the heart, arteries and veins, but it may also be used to image the motion of solid tissues such as the heart walls. Colour Doppler imaging is now provided on almost all commercial ultrasound machines, and has been...... vectors. This review briefly introduces the principles behind colour Doppler imaging and describes some clinical applications. It then describes the basic components of conventional colour Doppler systems and the methods used to derive velocity information from the ultrasound signal. Next, a number of new...

  3. Ultrasonic colour Doppler imaging

    DEFF Research Database (Denmark)

    Evans, David H; Jensen, Jørgen Arendt; Nielsen, Michael Bachmann

    2011-01-01

    Ultrasonic colour Doppler is an imaging technique that combines anatomical information derived using ultrasonic pulse-echo techniques with velocity information derived using ultrasonic Doppler techniques to generate colour-coded maps of tissue velocity superimposed on grey-scale images of tissue...... anatomy. The most common use of the technique is to image the movement of blood through the heart, arteries and veins, but it may also be used to image the motion of solid tissues such as the heart walls. Colour Doppler imaging is now provided on almost all commercial ultrasound machines, and has been...

  4. Phase width reduction project summary

    International Nuclear Information System (INIS)

    Clark, D.J.; Xie, Z.Q.; McMahan, M. A.

    1999-01-01

    The purpose of the phase width reduction project, 1993--96, was to reduce the phase width of the 88-Inch Cyclotron beam on target from 5--10 ns to 1--2 ns for certain experiments, such as Gammasphere, which use time-of-flight identification. Since reducing the phase width also reduces beam intensity, tuning should be done to also optimize the transmission. The Multi-turn Collimator slits in the cyclotron center region were used to collimate the early turns radially, thus reducing the phase width from about 5 ns to 1--2 ns FWHM for a Gammasphere beam. The effect of the slits on phase width was verified with a Fast Faraday Cup and with particle and gamma-ray detectors in the external beamline

  5. A deterministic width function model

    Directory of Open Access Journals (Sweden)

    C. E. Puente

    2003-01-01

    Full Text Available Use of a deterministic fractal-multifractal (FM geometric method to model width functions of natural river networks, as derived distributions of simple multifractal measures via fractal interpolating functions, is reported. It is first demonstrated that the FM procedure may be used to simulate natural width functions, preserving their most relevant features like their overall shape and texture and their observed power-law scaling on their power spectra. It is then shown, via two natural river networks (Racoon and Brushy creeks in the United States, that the FM approach may also be used to closely approximate existing width functions.

  6. Probabilistic Analysis of Crack Width

    Directory of Open Access Journals (Sweden)

    J. Marková

    2000-01-01

    Full Text Available Probabilistic analysis of crack width of a reinforced concrete element is based on the formulas accepted in Eurocode 2 and European Model Code 90. Obtained values of reliability index b seem to be satisfactory for the reinforced concrete slab that fulfils requirements for the crack width specified in Eurocode 2. However, the reliability of the slab seems to be insufficient when the European Model Code 90 is considered; reliability index is less than recommended value 1.5 for serviceability limit states indicated in Eurocode 1. Analysis of sensitivity factors of basic variables enables to find out variables significantly affecting the total crack width.

  7. Steerable Doppler transducer probes

    International Nuclear Information System (INIS)

    Fidel, H.F.; Greenwood, D.L.

    1986-01-01

    An ultrasonic diagnostic probe is described which is capable of performing ultrasonic imaging and Doppler measurement consisting of: a hollow case having an acoustic window which passes ultrasonic energy and including chamber means for containing fluid located within the hollow case and adjacent to a portion of the acoustic window; imaging transducer means, located in the hollow case and outside the fluid chamber means, and oriented to direct ultrasonic energy through the acoustic window toward an area which is to be imaged; Doppler transducer means, located in the hollow case within the fluid chamber means, and movably oriented to direct Doppler signals through the acoustic window toward the imaged area; means located within the fluid chamber means and externally controlled for controllably moving the Doppler transducer means to select one of a plurality of axes in the imaged area along which the Doppler signals are to be directed; and means, located external to the fluid chamber means and responsive to the means for moving, for providing an indication signal for identifying the selected axis

  8. Probabilistic Analysis of Crack Width

    OpenAIRE

    J. Marková; M. Holický

    2000-01-01

    Probabilistic analysis of crack width of a reinforced concrete element is based on the formulas accepted in Eurocode 2 and European Model Code 90. Obtained values of reliability index b seem to be satisfactory for the reinforced concrete slab that fulfils requirements for the crack width specified in Eurocode 2. However, the reliability of the slab seems to be insufficient when the European Model Code 90 is considered; reliability index is less than recommended value 1.5 for serviceabi...

  9. Unusual Ionospheric Echoes with Velocity and Very Low Special Width Observed by the SuperDARN Radars in the Polar Cap During High Geomagnetic Activity

    National Research Council Canada - National Science Library

    Nishitani, Nozomu

    2004-01-01

    ...) They have a close correlation with geomagnetic activity such that as the Dst index decreases, the radars tend to observe ionospheric echoes with high Doppler velocity and very low spectral width more frequently. (2...

  10. Pulse Doppler radar

    CERN Document Server

    Alabaster, Clive

    2012-01-01

    This book is a practitioner's guide to all aspects of pulse Doppler radar. It concentrates on airborne military radar systems since they are the most used, most complex, and most interesting of the pulse Doppler radars; however, ground-based and non-military systems are also included. It covers the fundamental science, signal processing, hardware issues, systems design and case studies of typical systems. It will be a useful resource for engineers of all types (hardware, software and systems), academics, post-graduate students, scientists in radar and radar electronic warfare sectors and milit

  11. Doppler radar physiological sensing

    CERN Document Server

    Lubecke, Victor M; Droitcour, Amy D; Park, Byung-Kwon; Singh, Aditya

    2016-01-01

    Presents a comprehensive description of the theory and practical implementation of Doppler radar-based physiological monitoring. This book includes an overview of current physiological monitoring techniques and explains the fundamental technology used in remote non-contact monitoring methods. Basic radio wave propagation and radar principles are introduced along with the fundamentals of physiological motion and measurement. Specific design and implementation considerations for physiological monitoring radar systems are then discussed in detail. The authors address current research and commercial development of Doppler radar based physiological monitoring for healthcare and other applications.

  12. Correlation between interalar width and intercommisural width against mesiodistal width of central upper incisor in Buginese tribe

    Directory of Open Access Journals (Sweden)

    Bahruddin Thalib

    2016-04-01

    Full Text Available Various types of anatomical landmarks of the face should match its proportions with the size of the teeth which is the interalar width, intercomissural width, interpupillary width, Intercanthal width, and byzigomatic width. Some of face landmarks can be used as a guide in the selection of anterior teeth in complete denture, especially if the pre extraction record such as radiography image, extracted teeth, model study, the remaining teeth, face shape, and the shape of the curved jaw have been lost. The objective of this study was to evaluate the correlation between interalar width and intercommisural width against mesiodistal incisivus centralis width in a group of Buginese tribe. Ninety nine Buginese tribe subjects aged 17-25 were selected. The interalar width, intercommisural width, and mesiodistal incisor centralis teeth were measured using caliper about three times for accuracy and precision. Mean of interalar width and mesiodistal incisor centralis maxilla width in males more width than females (p0.05. The degree of correlation between interalar width against mesiodistal incisor centralis maxilla width was 0.030, -0.246, 0,225 in Buginese tribe, males, and females (p>0.05. : The degree of correlation between intercommisural width against  mesiodistal incisor centralis maxilla width in Buginese tribe was 0,054, 0,013, 0,153 in Buginese tribe, males, and females (p>0.05. The degree of correlation between interalar width and intercommisural width was 0.301 and 0.356 in Buginese tribe and males (p0.05. In conclusion, there is no significant correlation between interalar width and intercommisural width against mesiodistal incisor centralis maxilla width in a group of Buginese tribe. Interalar width and intercommisural width  directly proportional to mesiodistal incisor centralis maxilla in a group of Buginese tribe. Interalar width and intercommisural width  inversely proportional to mesiodistal incisor centralis maxilla in males and directly

  13. Doppler-musical instrument

    International Nuclear Information System (INIS)

    Sato, T.J.; Watanabe, N.

    2001-01-01

    We propose a possible ultra-high energy resolution backscattering spectrometer optimized to spallation neutron source. A combination of multi monochromator crystal and Doppler drive provides considerable neutron flux, together with the reasonable energy range -30 < E < 30 μeV, even when the ultra-high energy resolution of ΔE∼0.03 μeV is attained. (author)

  14. Scanning laser Doppler vibrometry

    DEFF Research Database (Denmark)

    Brøns, Marie; Thomsen, Jon Juel

    With a Scanning Laser Doppler Vibrometer (SLDV) a vibrating surface is automatically scanned over predefined grid points, and data processed for displaying vibration properties like mode shapes, natural frequencies, damping ratios, and operational deflection shapes. Our SLDV – a PSV-500H from...

  15. Doppler Spectral Characteristics of High Latitude Ionospheric Irregularities: Effect on HF Radars.

    Science.gov (United States)

    1981-05-01

    DAOP (V) =50090 E-FDLDING DISTANCE OF ARRL E-FIELD(OEGREES) =5 LATITUDE OF POTENTIAL MAXIMUM(DEGREES) =70 OVAL OFFSET<DEGREES) a S MEASUREMENT LATITUDE...DOPPLER WIDT14 CROSS POLAR CAP POTENTIAL DAOP (V) =50000 E-FOLDING DISTANCE OF RRORAL E-FIELD(DEGAEES) =5 LATITUDE OF PDTENTIAL" MPXIMUM(DEGREES) = 70 OVAL...60 -Al1l - jiU 4,1 8.53 12.5 16.3 26.5s 24,#* * U *m U 10 tm 4- U U7 Ito oU LOCAL TIME DOPPLER VELOCITY DOPPLER WIDTH CROSS POLAR CAP POTENTIAL DAOP

  16. Laser doppler perfusion imaging

    International Nuclear Information System (INIS)

    Waardell, K.

    1992-01-01

    Recording of tissue perfusion is important in assessing the influence of peripheral vascular diseases on the microcirculation. This thesis reports on a laser doppler perfusion imager based on dynamic light scattering in tissue. When a low power He-Ne laser beam sequentally scans the tissue, moving blood cells generate doppler components in the back-scattered light. A fraction of this light is detected by a photodetector and converted into an electrical signal. In the processor, a signal proportional to the tissue perfusion at each measurement site is calculated and stored. When the scanning procedure is completed, a color-coded perfusion image is presented on a monitor. To convert important aspects of the perfusion image into more quantitative parameters, data analysis functions are implemented in the software. A theory describing the dependence of the distance between individual measurement points and detector on the system amplification factor is proposed and correction algorithms are presented. The performance of the laser doppler perfusion imager was evaluated using a flow simulator. A linear relationship between processor output signal and flow through the simulator was demonstrated for blood cell concentrations below 0.2%. The median sampling depth of the laser beam was simulated by a Monte Carlo technique and estimated to 235 μm. The perfusion imager has been used in the clinic to study perfusion changes in port wine stains treated with argon laser and to investigate the intensity and extension of the cutaneous axon reflex response after electrical nerve stimulation. The fact that perfusion can be visualized without touching the tissue implies elimination of sterilization problems, thus simplifying clinical investigations of perfusion in association with diagnosis and treatment of peripheral vascular diseases. 22 refs

  17. Marine Tar Residues: a Review

    OpenAIRE

    Warnock, April M.; Hagen, Scott C.; Passeri, Davina L.

    2015-01-01

    Marine tar residues originate from natural and anthropogenic oil releases into the ocean environment and are formed after liquid petroleum is transformed by weathering, sedimentation, and other processes. Tar balls, tar mats, and tar patties are common examples of marine tar residues and can range in size from millimeters in diameter (tar balls) to several meters in length and width (tar mats). These residues can remain in the ocean environment indefinitely, decomposing or becoming buried in ...

  18. Adaptive Spectral Doppler Estimation

    DEFF Research Database (Denmark)

    Gran, Fredrik; Jakobsson, Andreas; Jensen, Jørgen Arendt

    2009-01-01

    . The methods can also provide better quality of the estimated power spectral density (PSD) of the blood signal. Adaptive spectral estimation techniques are known to pro- vide good spectral resolution and contrast even when the ob- servation window is very short. The 2 adaptive techniques are tested......In this paper, 2 adaptive spectral estimation techniques are analyzed for spectral Doppler ultrasound. The purpose is to minimize the observation window needed to estimate the spectrogram to provide a better temporal resolution and gain more flexibility when designing the data acquisition sequence...... and compared with the averaged periodogram (Welch’s method). The blood power spectral capon (BPC) method is based on a standard minimum variance technique adapted to account for both averaging over slow-time and depth. The blood amplitude and phase estimation technique (BAPES) is based on finding a set...

  19. Residual deposits (residual soil)

    International Nuclear Information System (INIS)

    Khasanov, A.Kh.

    1988-01-01

    Residual soil deposits is accumulation of new formate ore minerals on the earth surface, arise as a result of chemical decomposition of rocks. As is well known, at the hyper genes zone under the influence of different factors (water, carbonic acid, organic acids, oxygen, microorganism activity) passes chemical weathering of rocks. Residual soil deposits forming depends from complex of geologic and climatic factors and also from composition and physical and chemical properties of initial rocks

  20. Turbulence Spectral Widths View Angle Independence as Observed by Doppler Radar

    Science.gov (United States)

    1989-10-01

    t, 1*+ 0 1T t+ ( 10) 2.+ 1I+. 3 3 1 9 Z1 9 1 1 21 S I 10 30 .. 1 11 30 49 3 D. 10 33 !’~3 . 02 2. F6 ’ -36 6 3 6 5 so 6 6 31 If., 68r t+.+ I’. . . .I... ACCA . .. AbA Co. CA•,A~ ... . ... C . .* CC~ CC C .... AC ... C . AC... CC CC . . . .. AAA C A 52CCC.CCCC A C AC. 51. CC 37. A. CACC C Cb...coeCcients b t e. and CCC ’l C. ..... .. o. oCA . .... °AACAA CC * C ... C 12.)0 35. 39. ’.. ’.5. A.. 37. 51 . 18. A• ACCA CCCCCCCCCCCCCCCCCCCCCC

  1. Doppler characteristics of sea clutter.

    Energy Technology Data Exchange (ETDEWEB)

    Raynal, Ann Marie; Doerry, Armin Walter

    2010-06-01

    Doppler radars can distinguish targets from clutter if the target's velocity along the radar line of sight is beyond that of the clutter. Some targets of interest may have a Doppler shift similar to that of clutter. The nature of sea clutter is different in the clutter and exo-clutter regions. This behavior requires special consideration regarding where a radar can expect to find sea-clutter returns in Doppler space and what detection algorithms are most appropriate to help mitigate false alarms and increase probability of detection of a target. This paper studies the existing state-of-the-art in the understanding of Doppler characteristics of sea clutter and scattering from the ocean to better understand the design and performance choices of a radar in differentiating targets from clutter under prevailing sea conditions.

  2. Dual-Doppler Feasibility Study

    Science.gov (United States)

    Huddleston, Lisa L.

    2012-01-01

    When two or more Doppler weather radar systems are monitoring the same region, the Doppler velocities can be combined to form a three-dimensional (3-D) wind vector field thus providing for a more intuitive analysis of the wind field. A real-time display of the 3-D winds can assist forecasters in predicting the onset of convection and severe weather. The data can also be used to initialize local numerical weather prediction models. Two operational Doppler Radar systems are in the vicinity of Kennedy Space Center (KSC) and Cape Canaveral Air Force Station (CCAFS); these systems are operated by the 45th Space Wing (45 SW) and the National Weather Service Melbourne, Fla. (NWS MLB). Dual-Doppler applications were considered by the 45 SW in choosing the site for the new radar. Accordingly, the 45th Weather Squadron (45 WS), NWS MLB and the National Aeronautics and Space Administration tasked the Applied Meteorology Unit (AMU) to investigate the feasibility of establishing dual-Doppler capability using the two existing systems. This study investigated technical, hardware, and software requirements necessary to enable the establishment of a dual-Doppler capability. Review of the available literature pertaining to the dual-Doppler technique and consultation with experts revealed that the physical locations and resulting beam crossing angles of the 45 SW and NWS MLB radars make them ideally suited for a dual-Doppler capability. The dual-Doppler equations were derived to facilitate complete understanding of dual-Doppler synthesis; to determine the technical information requirements; and to determine the components of wind velocity from the equation of continuity and radial velocity data collected by the two Doppler radars. Analysis confirmed the suitability of the existing systems to provide the desired capability. In addition, it is possible that both 45 SW radar data and Terminal Doppler Weather Radar data from Orlando International Airport could be used to alleviate any

  3. Color doppler in clinical cardiology

    International Nuclear Information System (INIS)

    Duncan, W.J.

    1987-01-01

    A presentation of color doppler, which enables physicians to pinpoint problems and develop effective treatment. State-of-the-art illustrations and layout, with color images and explanatory text are included

  4. Turbulence as observed by concurrent measurements made at NSSL using weather radar, Doppler radar, Doppler lidar and aircraft

    Science.gov (United States)

    Lee, Jean T.

    1987-01-01

    As air traffic increases and aircraft capability increases in range and operating altitude, the exposure to weather hazards increases. Turbulence and wind shears are two of the most important of these hazards that must be taken into account if safe flight operations are to be accomplished. Beginning in the early 1960's, Project Rough Rider began thunderstorm investigations. Past and present efforts at the National Severe Storm Laboratory (NSSL) to measure these flight safety hazards and to describe the use of Doppler radar to detect and qualify these hazards are summarized. In particular, the evolution of the Doppler-measured radial velocity spectrum width and its applicability to the problem of safe flight is presented.

  5. The effect of gap width on viscous stresses within the leakage across a bileaflet valve pivot

    DEFF Research Database (Denmark)

    Travis, Brandon R; Andersen, Morten E; Fründ, Ernst Torben

    2008-01-01

    BACKGROUND AND AIM OF THE STUDY: Stresses of leakage flow may contribute to the increased tendency for thromboembolic complications in patients with mechanical valves. In bileaflet valves, leakage occurs primarily in the pivots, and the width of the pivot gap influences viscous stress magnitudes...... were performed, varying gap width between the leaflet and housing in the pivot region. To validate these calculations, steady leakage across a scaled in-vitro model of a single pivot was initiated, and velocity measurements at specific locations within flow the pivot were obtained using one......-component laser Doppler velocimetry. RESULTS: The average viscous stresses on the housing surface of the pivot increased from 198 to 299 Pa, and on the leaflet surface from 242 to 271 Pa, as gap width was increased from 100 to 300 microm. These stresses were similar in magnitude to the maximum turbulent stresses...

  6. Coherent compounding in doppler imaging.

    Science.gov (United States)

    Ekroll, Ingvild K; Voormolen, Marco M; Standal, Oyvind K-V; Rau, Jochen M; Lovstakken, Lasse

    2015-09-01

    Coherent compounding can provide high frame rates and wide regions of interest for imaging of blood flow. However, motion will cause out-of-phase summation, potentially causing image degradation. In this work the impact of blood motion on SNR and the accuracy of Doppler velocity estimates are investigated. A simplified model for the compounded Doppler signal is proposed. The model is used to show that coherent compounding acts as a low-pass filter on the coherent compounding Doppler signal, resulting in negatively biased velocity estimates. Simulations and flow phantom experiments are used to quantify the bias and Doppler SNR for different velocities and beam-to-flow (BTF) angles. It is shown that the bias in the mean velocity increases with increasing beam-to-flow angle and/or blood velocity, whereas the SNR decreases; losses up to 4 dB were observed in the investigated scenarios. Further, a 2-D motion correction scheme is proposed based on multi-angle vector Doppler velocity estimates. For a velocity of 1.1 v(Nyq) and a BTF angle of 75°, the bias was reduced from 30% to less than 4% in simulations. The motion correction scheme was also applied to flow phantom and in vivo recordings, in both cases resulting in a substantially reduced mean velocity bias and an SNR less dependent on blood velocity and direction.

  7. A niche width model of optimal specialization

    NARCIS (Netherlands)

    Bruggeman, J.P.; Ó Nualláin, Breanndán

    2000-01-01

    Niche width theory, a part of organizational ecology, predicts whether “specialist” or “generalist” forms of organizations have higher “fitness,” in a continually changing environment. To this end, niche width theory uses a mathematical model borrowed from biology. In this paper, we first loosen the

  8. Constant Width Planar Computation Characterizes ACC0

    DEFF Research Database (Denmark)

    Hansen, K.A.

    2004-01-01

    We obtain a characterization of ACC 0 in terms of a natural class of constant width circuits, namely in terms of constant width polynomial size planar circuits. This is shown via a characterization of the class of acyclic digraphs which can be embedded on a cylinder surface in such a way that all...

  9. Constant Width Planar Computation Characterizes ACC0

    DEFF Research Database (Denmark)

    Hansen, Kristoffer Arnsfelt

    2006-01-01

    We obtain a characterization of ACC0 in terms of a natural class of constant width circuits, namely in terms of constant width polynomial size planar circuits. This is shown via a characterization of the class of acyclic digraphs which can be embedded on a cylinder surface in such a way that all...

  10. 7 CFR 29.1085 - Width.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Width. 29.1085 Section 29.1085 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Heavy Fleshy Medium Thin Oil Lean Oily Rich Color intensity Pale Weak Moderate Strong Deep. Width...

  11. Detection of gravitational radiation by the Doppler tracking of spacecraft

    International Nuclear Information System (INIS)

    Mashhoon, B.

    1979-01-01

    It has been suggested that the residual Doppler shift in the precision electromagnetic tracking of spacecraft be used to search for gravitational radiation that may be incident on the Earth-spacecraft system. The influence of a gravitational wave on the Doppler shift is calculated, and it is found that the residual shift is dominated by two terms: one is due to the passage of electromagnetic waves through the gravitational radiation field, and the other depends on the change in the relative velocity of the Earth and the spacecraft caused by the external wave. A detailed analysis is given of the influence of gravitational radiation on a binary system with an orbital size small compared to the wavelength of the incident radiation. It is shown that, as a consequence of the interaction with the external wave, the system makes a transition from one Keplerian orbit into another which, in general, has a different energy and angular momentum. It is therefore proposed to search for such effects in the solar system. Observations of the orbit of an artificial Earth satellite, the lunar orbit, and especially the planetary orbits offer exciting possibilities for the detection of gravitational waves of various wavelengths. From the results of the lunar laser ranging experiment and the range measurement to Mars, certain interesting limits may be established on the frequency of incidence of gravitational waves of a given flux on the Earth-Moon and the Earth-Mars systems. This is followed by a brief and preliminary analysis of the possibility of detecting gravitational radiation by measuring a residual secular Doppler shift in the satellite-to-satellite Doppler tracking of two counterorbiting drag-free spacecraft around the Earth as in the Van Patten-Everitt experiment

  12. An inter-hemispheric, statistical study of nightside spectral width distributions from coherent HF scatter radars

    Directory of Open Access Journals (Sweden)

    E. E. Woodfield

    2002-12-01

    Full Text Available A statistical investigation of the Doppler spectral width parameter routinely observed by HF coherent radars has been conducted between the Northern and Southern Hemispheres for the nightside ionosphere. Data from the SuperDARN radars at Thykkvibær, Iceland and Syowa East, Antarctica have been employed for this purpose. Both radars frequently observe regions of high (>200 ms-1 spectral width polewards of low (<200 ms-1 spectral width. Three years of data from both radars have been analysed both for the spectral width and line of sight velocity. The pointing direction of these two radars is such that the flow reversal boundary may be estimated from the velocity data, and therefore, we have an estimate of the open/closed field line boundary location for comparison with the high spectral widths. Five key observations regarding the behaviour of the spectral width on the nightside have been made. These are (i the two radars observe similar characteristics on a statistical basis; (ii a latitudinal dependence related to magnetic local time is found in both hemispheres; (iii a seasonal dependence of the spectral width is observed by both radars, which shows a marked absence of latitudinal dependence during the summer months; (iv in general, the Syowa East spectral width tends to be larger than that from Iceland East, and (v the highest spectral widths seem to appear on both open and closed field lines. Points (i and (ii indicate that the cause of high spectral width is magnetospheric in origin. Point (iii suggests that either the propagation of the HF radio waves to regions of high spectral width or the generating mechanism(s for high spectral width is affected by solar illumination or other seasonal effects. Point (iv suggests that the radar beams from each of the radars are subject either to different instrumental or propagation effects, or different geophysical conditions due to their locations, although we suggest that this result is more likely to

  13. An inter-hemispheric, statistical study of nightside spectral width distributions from coherent HF scatter radars

    Directory of Open Access Journals (Sweden)

    E. E. Woodfield

    Full Text Available A statistical investigation of the Doppler spectral width parameter routinely observed by HF coherent radars has been conducted between the Northern and Southern Hemispheres for the nightside ionosphere. Data from the SuperDARN radars at Thykkvibær, Iceland and Syowa East, Antarctica have been employed for this purpose. Both radars frequently observe regions of high (>200 ms-1 spectral width polewards of low (<200 ms-1 spectral width. Three years of data from both radars have been analysed both for the spectral width and line of sight velocity. The pointing direction of these two radars is such that the flow reversal boundary may be estimated from the velocity data, and therefore, we have an estimate of the open/closed field line boundary location for comparison with the high spectral widths. Five key observations regarding the behaviour of the spectral width on the nightside have been made. These are (i the two radars observe similar characteristics on a statistical basis; (ii a latitudinal dependence related to magnetic local time is found in both hemispheres; (iii a seasonal dependence of the spectral width is observed by both radars, which shows a marked absence of latitudinal dependence during the summer months; (iv in general, the Syowa East spectral width tends to be larger than that from Iceland East, and (v the highest spectral widths seem to appear on both open and closed field lines. Points (i and (ii indicate that the cause of high spectral width is magnetospheric in origin. Point (iii suggests that either the propagation of the HF radio waves to regions of high spectral width or the generating mechanism(s for high spectral width is affected by solar illumination or other seasonal effects. Point (iv suggests that the radar beams from each of the radars are subject either to different instrumental or propagation effects, or different geophysical conditions due to their locations, although we suggest that this

  14. General principles of carotid Doppler ultrasonography

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Whal [Dept. of Radiology, Seoul National University College of Medicine, Seoul (Korea, Republic of)

    2014-03-15

    Carotid Doppler ultrasonography is a popular tool for evaluating atherosclerosis of the carotid artery. Its two-dimensional gray scale can be used for measuring the intima-media thickness, which is very good biomarker for atherosclerosis and can aid in plaque characterization. The plaque morphology is related to the risk of stroke. The ulceration of plaque is also known as one of the strong predictors of future embolic event risk. Color Doppler ultrasonography and pulse Doppler ultrasonography have been used for detecting carotid artery stenosis. Doppler ultrasonography has unique physical properties. The operator should be familiar with the physics and other parameters of Doppler ultrasonography to perform optimal Doppler ultrasonography studies.

  15. Doppler echocardiography in pediatric cardiology

    International Nuclear Information System (INIS)

    Allen, H.D.; Marx, G.R.

    1986-01-01

    Congenital heart disease encompasses abnormalities in cardiac development which generally have in common either valve stenoses or connections between chambers or great vessels. Usually, abnormalities of intracardiac anatomy, and often, abnormalities of great vessel anatomy, can be unraveled by two-dimensional echocardiography. However, echocardiography offers little information regarding flow characteristics in the various congenital lesions. Addition of the Doppler principle, particularly when combined with the two-dimensional examination, can characterize the source of a flow disturbance, quantify gradients across a site of obstruction, and quantify flow volume across sites where flow is nonturbulent. These features make Doppler echocardiography unique for noninvasive accurate evaluation of children and adults with various forms of congenital heart disease. In this report, the authors discuss some of the present uses of Doppler echocardiography in congenital heart disease. Application of this technique requires greater understanding of certain physics principles than does routine echocardiography

  16. Biologic width dimensions--a systematic review.

    Science.gov (United States)

    Schmidt, Julia C; Sahrmann, Philipp; Weiger, Roland; Schmidlin, Patrick R; Walter, Clemens

    2013-05-01

    Consideration of the biologic width in restorative dentistry seems to be important for maintaining periodontal health. To evaluate the dimensions of the biologic width in humans. A systematic literature search was performed for publications published by 28 September 2012 using five different electronic databases; this search was complemented by a manual search. Two reviewers conducted the study selection, data collection, and validity assessment. The PRISMA criteria were applied. From 615 titles identified by the search strategy, 14 publications were included and six were suitable for meta-analyses. Included studies were published from the years 1924 to 2012. They differed with regard to measurements of the biologic width. Mean values of the biologic width obtained from two meta-analyses ranged from 2.15 to 2.30 mm, but large intra- and inter-individual variances (subject sample range: 0.2 - 6.73 mm) were observed. The tooth type and site, the presence of a restoration and periodontal diseases/surgery affected the dimensions of the biologic width. Pronounced heterogeneity among studies regarding methods and outcome measures exists. No universal dimension of the biologic width appears to exist. Establishment of periodontal health is suggested prior to the assessment of the biologic width within reconstructive dentistry. © 2013 John Wiley & Sons A/S.

  17. Nonlinear narrow Doppler-free resonances for optical transitions and annihilation radiation of a positronium atom

    International Nuclear Information System (INIS)

    Letokhov, V.S.; Minogin, V.G.

    1976-01-01

    The possibilities of obtaining narrow resonances without the Doppler broadening for transition between the fine structure levels of the ground and first excited states of a positronium atom are considered. An analysis is carried out of the conditions required for observation of the narrow resonances of saturation of single quantum absorption in the 1S-2P transitions and observation of narrow two-photon absorption resonances in the 1S-2S transitions. It is shown that narrow 2γ annihilation radiation lines of a positronium atom may be obtained with a width much smaller than the Doppler one

  18. Micro-Doppler Analysis of Small UAVs

    NARCIS (Netherlands)

    Wit, J.J.M. de; Harmanny, R.I.A.; Prémel Cabic, G.

    2012-01-01

    Coherent radar measures micro-Doppler properties of moving objects. The micro-Doppler signature depends on parts of an object moving and rotating in addition to the main body motion (e.g. rotor blades) and is therefore characteristic for the type of object. In this study, the micro-Doppler signature

  19. Direct measurement of the W boson width

    International Nuclear Information System (INIS)

    Abe, F.; Albrow, M.G.; Amidei, D.; Antos, J.; Anway-Wiese, C.; Apollinari, G.; Areti, H.; Atac, M.; Auchincloss, P.; Azfar, F.; Azzi, P.; Bacchetta, N.; Badgett, W.; Bailey, M.W.; Bao, J.; de Barbaro, P.; Barbaro-Galtieri, A.; Barnes, V.E.; Barnett, B.A.; Bartalini, P.; Bauer, G.; Baumann, T.; Bedeschi, F.; Behrends, S.; Belforte, S.; Bellettini, G.; Bellinger, J.; Benjamin, D.; Benlloch, J.; Bensinger, J.; Benton, D.; Beretvas, A.; Berge, J.P.; Bertolucci, S.; Bhatti, A.; Biery, K.; Binkley, M.; Bird, F.; Bisello, D.; Blair, R.E.; Blocker, C.; Bodek, A.; Bokhari, W.; Bolognesi, V.; Bortoletto, D.; Boswell, C.; Boulos, T.; Brandenburg, G.; Buckley-Geer, E.; Budd, H.S.; Burkett, K.; Busetto, G.; Byon-Wagner, A.; Byrum, K.L.; Cammerata, J.; Campagnari, C.; Campbell, M.; Caner, A.; Carithers, W.; Carlsmith, D.; Castro, A.; Cen, Y.; Cervelli, F.; Chapman, J.; Cheng, M.; Chiarelli, G.; Chikamatsu, T.; Cihangir, S.; Clark, A.G.; Cobal, M.; Contreras, M.; Conway, J.; Cooper, J.; Cordelli, M.; Crane, D.; Cunningham, J.D.; Daniels, T.; DeJongh, F.; Delchamps, S.; Dell'Agnello, S.; Dell'Orso, M.; Demortier, L.; Denby, B.; Deninno, M.; Derwent, P.F.; Devlin, T.; Dickson, M.; Donati, S.; Drucker, R.B.; Dunn, A.; Einsweiler, K.; Elias, J.E.; Ely, R.; Engels, E. Jr.; Eno, S.; Errede, D.; Errede, S.; Fan, Q.; Farhat, B.; Fiori, I.; Flaugher, B.; Foster, G.W.; Franklin, M.; Frautschi, M.; Freeman, J.; Friedman, J.; Frisch, H.; Fry, A.; Fuess, T.A.; Fukui, Y.; Funaki, S.; Gagliardi, G.; Galeotti, S.; Gallinaro, M.; Garfinkel, A.F.; Geer, S.; Gerdes, D.W.; Giannetti, P.; Giokaris, N.; Giromini, P.; Gladney, L.; Glenzinski, D.; Gold, M.; Gonzalez, J.; Gordon, A.; Goshaw, A.T.; Goulianos, K.; Grassmann, H.; Grewal, A.; Grieco, G.; Groer, L.; Grosso-Pilcher, C.; Haber, C.; Hahn, S.R.; Hamilton, R.; Handler, R.; Hans, R.M.; Hara, K.; Harral, B.; Harris, R.M.; Hauger, S.A.; Hauser, J.; Hawk, C.; Heinrich, J.; Cronin-Hennessy, D.; Hollebeek, R.; Holloway, L.; Hoelscher, A.

    1995-01-01

    This Letter describes a direct measurement of the W boson decay width, Γ(W), using the high-mass tail of the transverse mass spectrum of W→eν decays recorded by the Collider Detector at Fermilab. We find Γ(W)=2.11±0.28(stat) ± 0.16(syst) GeV and compare this direct measurement with indirect means of obtaining the width

  20. Changes in Doppler waveforms can predict pressure reduction across internal carotid artery stenoses

    DEFF Research Database (Denmark)

    Sillesen, H; Schroeder, T

    1988-01-01

    Cerebral ischemia can result from either embolism or be due to hemodynamic failure. The purpose of this study was to evaluate whether Doppler waveforms, obtained distal to an internal carotid artery (ICA) stenosis, could predict the degree of hemodynamic compromise in terms of reduction in cerebral...... perfusion pressure. Forty-nine patients were examined consecutively with ultrasound Doppler prior to carotid endarterectomy. Pulsatility index (PI), pulse rise-time (RT), and systolic width (SW) were related to angiographic degree of stenosis and the ratio of distal ICA blood pressure to common carotid...... be predicted with an accuracy of 90-95%. Correlating the waveform parameters with arteriography was less convincing, reaching the level of statistical significance for PI only. ICA Doppler waveforms, obtained as distal in the neck as possible can accurately predict the degree of hemodynamic compromise...

  1. Quantum black hole wave packet: Average area entropy and temperature dependent width

    Directory of Open Access Journals (Sweden)

    Aharon Davidson

    2014-09-01

    Full Text Available A quantum Schwarzschild black hole is described, at the mini super spacetime level, by a non-singular wave packet composed of plane wave eigenstates of the momentum Dirac-conjugate to the mass operator. The entropy of the mass spectrum acquires then independent contributions from the average mass and the width. Hence, Bekenstein's area entropy is formulated using the 〈mass2〉 average, leaving the 〈mass〉 average to set the Hawking temperature. The width function peaks at the Planck scale for an elementary (zero entropy, zero free energy micro black hole of finite rms size, and decreases Doppler-like towards the classical limit.

  2. Line-RALF Doppler Velocimetry

    Science.gov (United States)

    Fajardo, Mario

    2017-06-01

    We report the successful proof-of-concept demonstration of a 1D spatially-dependent variant of our Rubidium Atomic Line Filtered (RALF) Doppler velocimetry technique, using streak camera detection of laser light reflected from 1-mm-diameter laser-driven flyers traveling at 1 km/s. RALF employs the frequency-dependent near-resonant optical absorption of a heated Rb/N2 gas cell to convert the Doppler shift of reflected 780.24 nm light directly into transmitted light intensity. This approach results in each individual pixel in a RALF image constituting an independent velocity measurement. RALF advantages over conventional interferometric Doppler velocimetry methods include: a time response limited only by the optoelectronic detection system, and facile adaptation for 1D, and even 2D, imaging velocimetry applications. RALF disadvantages include: the direct conversion of image intensity noise into calculated velocity noise, extreme sensitivity to loss of signal upon shock breakout, and poor tolerance of parasitic reflections of unshifted illumination laser light.

  3. The decay width of stringy hadrons

    Directory of Open Access Journals (Sweden)

    Jacob Sonnenschein

    2018-02-01

    We fit the theoretical decay width to experimental data for mesons on the trajectories of ρ, ω, π, η, K⁎, ϕ, D, and Ds⁎, and of the baryons N, Δ, Λ, and Σ. We examine both the linearity in L and the exponential suppression factor. The linearity was found to agree with the data well for mesons but less for baryons. The extracted coefficient for mesons A=0.095±0.015 is indeed quite universal. The exponential suppression was applied to both strong and radiative decays. We discuss the relation with string fragmentation and jet formation. We extract the quark–diquark structure of baryons from their decays. A stringy mechanism for Zweig suppressed decays of quarkonia is proposed and is shown to reproduce the decay width of ϒ states. The dependence of the width on spin and flavor symmetry is discussed. We further apply this model to the decays of glueballs and exotic hadrons.

  4. Relative Width and Height of Handwritten Letter.

    Science.gov (United States)

    Lizega Rika, Joseba

    2018-01-01

    This is an exploratory study that analyzes the width and the height of letters in two texts written by each of the 21 writers analyzed. After detrending the linear, text, and allograph trends, we proceeded to comparing the sizes obtained in different texts. The different detrended series were compared by means of correlation and t-test. According to the results regarding the width of letters, the texts of 19 of 21 writers correlated strongly, whereas the texts of two writers did not correlate with the limits of the threshold. With regard to the height of letters, texts written by between 18 and 21 writers of 21 writers correlated strongly, whereas texts that did not correlate were within the threshold value. Regarding both the width and the height of letters, of 21 writers, texts written by between 19 and 21 individuals were found to correlate strongly. © 2017 American Academy of Forensic Sciences.

  5. Alliances and Bisection Width for Planar Graphs

    DEFF Research Database (Denmark)

    Olsen, Martin; Revsbæk, Morten

    2013-01-01

    An alliance in a graph is a set of vertices (allies) such that each vertex in the alliance has at least as many allies (counting the vertex itself) as non-allies in its neighborhood of the graph. We show that any planar graph with minimum degree at least 4 can be split into two alliances...... in polynomial time. We base this on a proof of an upper bound of n on the bisection width for 4-connected planar graphs with an odd number of vertices. This improves a recently published n + 1 upper bound on the bisection width of planar graphs without separating triangles and supports the folklore conjecture...... that a general upper bound of n exists for the bisection width of planar graphs....

  6. Line width of Josephson flux flow oscillators

    DEFF Research Database (Denmark)

    Koshelets, V.P.; Dmitriev, P.N.; Sobolev, A.S.

    2002-01-01

    A combination of wide-band electronic tunability and moderate free-running line width makes the Josephson flux flow oscillator (FFO) a perfect on-chip local oscillator for integrated submillimeter-wave SIS receivers. The possibility of FFO phase locking at all frequencies of interest has...... to be proven before one initiates real FFO applications. To achieve this goal a comprehensive set of line width measurements of the FFO operating in different regimes has been performed. FFOs with tapered shape have been successfully implemented in order to avoid the superfine resonant structure with voltage...... spacing of about 20 nV and extremely low differential resistance, recently observed in the IVC of the standard rectangular geometry. The obtained results have been compared with existing theories and FFO models in order to understand and possibly eliminate excess noise in the FFO. The intrinsic line width...

  7. The decay width of stringy hadrons

    Science.gov (United States)

    Sonnenschein, Jacob; Weissman, Dorin

    2018-02-01

    In this paper we further develop a string model of hadrons by computing their strong decay widths and comparing them to experiment. The main decay mechanism is that of a string splitting into two strings. The corresponding total decay width behaves as Γ = π/2 ATL where T and L are the tension and length of the string and A is a dimensionless universal constant. We show that this result holds for a bosonic string not only in the critical dimension. The partial width of a given decay mode is given by Γi / Γ =Φi exp ⁡ (- 2 πCmsep2 / T) where Φi is a phase space factor, msep is the mass of the "quark" and "antiquark" created at the splitting point, and C is a dimensionless coefficient close to unity. Based on the spectra of hadrons we observe that their (modified) Regge trajectories are characterized by a negative intercept. This implies a repulsive Casimir force that gives the string a "zero point length". We fit the theoretical decay width to experimental data for mesons on the trajectories of ρ, ω, π, η, K*, ϕ, D, and Ds*, and of the baryons N, Δ, Λ, and Σ. We examine both the linearity in L and the exponential suppression factor. The linearity was found to agree with the data well for mesons but less for baryons. The extracted coefficient for mesons A = 0.095 ± 0.015 is indeed quite universal. The exponential suppression was applied to both strong and radiative decays. We discuss the relation with string fragmentation and jet formation. We extract the quark-diquark structure of baryons from their decays. A stringy mechanism for Zweig suppressed decays of quarkonia is proposed and is shown to reproduce the decay width of ϒ states. The dependence of the width on spin and flavor symmetry is discussed. We further apply this model to the decays of glueballs and exotic hadrons.

  8. Fatigue damage in superalloys determined using Doppler broadening positron annihilation

    Science.gov (United States)

    Hoeckelman, Donald; Leighly, H. P., Jr.

    1990-01-01

    Axial fatigue specimens of three superalloys, Inconel 718, Incoloy 903 and Haynes 188, were machined from solution-heat-treated material and artificially aged. They were subjected to cyclic loading for a selected number of cycles after which the S parameter was determined using Doppler broadening positron annihilation. Initially, the S parameter decreased, followed by a large increase and a subsequent decline leading to fracture. This has been interpreted as the removal of residual vacancies, the introduction of new defects by cyclic loading, and, finally, a clustering of the defects as microcracks which grow to cause failure.

  9. Temperature dependence of giant dipole resonance width

    International Nuclear Information System (INIS)

    Vdovin, A.I.; Storozhenko, A.N.

    2005-01-01

    The quasiparticle-phonon nuclear model extended to finite temperature within the framework of the thermo field dynamics is applied to calculate a temperature dependence of the spreading width Γ d own of a giant dipole resonance. Numerical calculations are made for 12S n and 208 Pb nuclei. It is found that the width Γ d own increases with T. The reason of this effect is discussed as well as a relation of the present approach to other ones existing in the literature

  10. Residuation theory

    CERN Document Server

    Blyth, T S; Sneddon, I N; Stark, M

    1972-01-01

    Residuation Theory aims to contribute to literature in the field of ordered algebraic structures, especially on the subject of residual mappings. The book is divided into three chapters. Chapter 1 focuses on ordered sets; directed sets; semilattices; lattices; and complete lattices. Chapter 2 tackles Baer rings; Baer semigroups; Foulis semigroups; residual mappings; the notion of involution; and Boolean algebras. Chapter 3 covers residuated groupoids and semigroups; group homomorphic and isotone homomorphic Boolean images of ordered semigroups; Dubreil-Jacotin and Brouwer semigroups; and loli

  11. Radiative width of molecular-cluster states

    International Nuclear Information System (INIS)

    Alhassid, Y.; Gai, M.; Bertsch, G.F.

    1982-01-01

    Molecular states are characterized by enhanced electromagnetic deexcitations of many different multipolarities. The expected enhancement of E1, E2, and E3 transitions is examined by deriving molecular sum rules for radiative deexcitation widths and via a dimensionality approach. The enhancement of the E1 transitions is the most striking

  12. Wireline equalization using pulse-width modulation

    NARCIS (Netherlands)

    Schrader, J.H.R.; Klumperink, Eric A.M.; Visschers, J.L.; Nauta, Bram

    2006-01-01

    Abstract-High-speed data links over copper cables can be effectively equalized using pulse-width modulation (PWM) pre-emphasis. This provides an alternative to the usual 2-tap FIR filters. The use of PWM pre-emphasis allows a channel loss at the Nyquist frequency of ~30dB, compared to ~20dB for a

  13. Comparison of Arch Width Changes Following Orthodontic ...

    African Journals Online (AJOL)

    2015-11-21

    Nov 21, 2015 ... they found optimal results are achieved when individual arch forms are maintained.[15]. This retrospective study used digital measurements of orthodontic models (1) to evaluate arch width changes in patients treated with fixed orthodontic appliances whose initial ovoid arch form was maintained following.

  14. Bounding the Higgs boson width through interferometry.

    Science.gov (United States)

    Dixon, Lance J; Li, Ye

    2013-09-13

    We study the change in the diphoton-invariant-mass distribution for Higgs boson decays to two photons, due to interference between the Higgs resonance in gluon fusion and the continuum background amplitude for gg→γγ. Previously, the apparent Higgs mass was found to shift by around 100 MeV in the standard model in the leading-order approximation, which may potentially be experimentally observable. We compute the next-to-leading-order QCD corrections to the apparent mass shift, which reduce it by about 40%. The apparent mass shift may provide a way to measure, or at least bound, the Higgs boson width at the Large Hadron Collider through "interferometry." We investigate how the shift depends on the Higgs width, in a model that maintains constant Higgs boson signal yields. At Higgs widths above 30 MeV, the mass shift is over 200 MeV and increases with the square root of the width. The apparent mass shift could be measured by comparing with the ZZ* channel, where the shift is much smaller. It might be possible to measure the shift more accurately by exploiting its strong dependence on the Higgs transverse momentum.

  15. Doppler tomography in fusion plasmas and astrophysics

    DEFF Research Database (Denmark)

    Salewski, Mirko; Geiger, B.; Heidbrink, W. W.

    2015-01-01

    Doppler tomography is a well-known method in astrophysics to image the accretion flow, often in the shape of thin discs, in compact binary stars. As accretion discs rotate, all emitted line radiation is Doppler-shifted. In fast-ion Dα (FIDA) spectroscopy measurements in magnetically confined plasma......, the Dα-photons are likewise Doppler-shifted ultimately due to gyration of the fast ions. In either case, spectra of Doppler-shifted line emission are sensitive to the velocity distribution of the emitters. Astrophysical Doppler tomography has lead to images of accretion discs of binaries revealing bright...... and limits, analogies and differences in astrophysical and fusion plasma Doppler tomography and what can be learned by comparison of these applications....

  16. Doppler effects on periodicities in Saturn's magnetosphere

    Science.gov (United States)

    Carbary, J. F.

    2015-11-01

    The magnetosphere of Saturn exhibits a wide variety of periodic phenomena in magnetic fields, charged particles, and radio emissions. The periodicities are observed from a moving spacecraft, so an issue arises about the periodicities being influenced by the Doppler effects. Doppler effects can be investigated using models of the periodicities and then flying the spacecraft through the model, effectively measuring any Doppler phenomena with the simulation. Using 200 days of typical elliptical orbits from the Cassini mission at Saturn, three models were tested: an azimuthal wave (or "searchlight") model, a radial wave (or "pond ripple") model, and a model of an outwardly traveling spiral wave. The azimuthal wave model produced virtually no Doppler effects in the periodicities because its wave vector is nearly perpendicular to the spacecraft trajectory. The radial wave model generated strong Doppler effects of an upshifted and a downshifted signal (a dual period) on either side of the true period, because the wave vector is either parallel or antiparallel to the spacecraft trajectory. Being intermediate to the searchlight and radial waves, the spiral wave produced Doppler effects but only for low wave speeds (<10 RS/h). For higher wave speeds the Doppler effects were not as clear. The Doppler effects can be mitigated by employing only observations beyond ~15 RS where the spacecraft speed is low compared to the wave speed. The observed periodicities over the same 200 day interval do not show evidence of Doppler effects but generally display a single feature at the expected ~10.7 h period.

  17. Correlation functions and power spectra of Doppler response signals in ultrasonic medical applications.

    Science.gov (United States)

    Skresanova, Iryna V; Barannik, Evgen A

    2012-07-01

    Ultrasound Doppler methods are widely used in clinical practice as prospective investigational tool to study the vascular system and soft biological tissues. Meanwhile, the most general relationship between the power Doppler spectra, spectral characteristics of the scattering fluctuations and the probing ultrasound field parameters for some clinical implementations are still unexplored. Based upon the continuum model of scattering inhomogeneities, a set of the closed-form expressions for the correlation functions and the spectra of Doppler response of soft tissues and blood have been derived. The influence of the correlation among inhomogeneities and the diffusion processes on the Doppler power spectra formed by stationary flows have been examined. Computer simulations of Doppler spectra were performed for different values of correlation radius and diffusion coefficient. With simulation results the effects of the correlation among inhomogeneities and the diffusion processes on the spectral width and mean frequency are established and discussed in respect to turbulent flows. Closed-form expressions for correlation functions and Doppler spectra for the vibrational sonoelastography technique for visualizing malignant tumors in tissues have been derived. Based on the peculiarities of the obtained Doppler spectra, it is shown that the differentiation of soft tissues with respect to the amplitude value of constrained oscillations is feasible. The expressions were derived for the cases of non-stationary accelerated blood movement. It has been found that the frequency dependence reveals solely at a finite time of observation and depends on the initial phase of the accelerated movement. Copyright © 2012 Elsevier B.V. All rights reserved.

  18. Doppler Monte Carlo simulations of light scattering in tissue to support laser-Doppler perfusion measurements

    NARCIS (Netherlands)

    de Mul, F.F.M.; Steenbergen, Wiendelt; Greve, Jan

    1999-01-01

    Doppler Monte Carlo (DMC) simulations of the transport of light through turbid media, e.g., tissue, can be used to predict or to interpret measurements of the blood perfusion of tissue by laser‐Doppler perfusion flowmetry. We describe the physical and mathematical background of Doppler Monte Carlo

  19. Wide angle Michelson Doppler imaging interferometer. [measuring atmospheric emissions

    Science.gov (United States)

    Shepherd, G. G.

    1980-01-01

    The optical system, stepping control, phase and modulation depth, array detector, and directions sensor are described for a specialized type of Michelson interferometer which works at sufficiently high resolution to measure the line widths and Doppler shifts of naturally occurring atmospheric emissions. With its imaging capability, the instrument can potentially supply this data independently for each element of the 100 x 100 detector array. The experiment seeks: (1) to obtain vertical profiles of atmospheric winds and temperatures as functions of latitude by observing near the limb; (2) to acquire exploratory wind and temperature data on smaller scale structures in airglow irregularities and in auroral forms; and (3) to collaborate with other Spacelab experiments, such as barium cloud releases, in providing wind and temperature data.

  20. Exotic meson decay widths using lattice QCD

    International Nuclear Information System (INIS)

    Cook, M. S.; Fiebig, H. R.

    2006-01-01

    A decay width calculation for a hybrid exotic meson h, with J PC =1 -+ , is presented for the channel h→πa 1 . This quenched lattice QCD simulation employs Luescher's finite box method. Operators coupling to the h and πa 1 states are used at various levels of smearing and fuzzing, and at four quark masses. Eigenvalues of the corresponding correlation matrices yield energy spectra that determine scattering phase shifts for a discrete set of relative πa 1 momenta. Although the phase shift data is sparse, fits to a Breit-Wigner model are attempted, resulting in a decay width of about 60 MeV when averaged over two lattice sizes having a lattice spacing of 0.07 fm

  1. Analysis of reduced widths and size

    International Nuclear Information System (INIS)

    Sharma, H.C.; Ram Raj; Nath, N.

    1977-01-01

    Recent data on S-wave neutron reduced widths for a large number of nuclei have been analysed nucleus-wise and the calculations for the degree of freedom of the associated (chi) 2 -distribution have been made using the Porter and Thomas procedure. It is noted that a number of nuclei can be fitted by a (chi) 2 -distribution with degree of freedom one, while there are few which are identified to follow a (chi) 2 -distribution with degree of freedom two and even more than two. The present analysis thus contradicts the usual presumption according to which the degree of freedom is taken to be always unity. An analytical attempt has also been made to ascertain the suitability of the data on reduced widths to be used for the analysis. These considerations are likely to modify the neutron cross-section evaluations. (author)

  2. Palindromic widths of nilpotent and wreath products

    Indian Academy of Sciences (India)

    This result was gen- eralized by Bardakov and Tolstykh [8] who proved that almost all free products have infinite palindromic width; the only exception is given by ..... Next, let X0 ⊆ X and Y0 ⊆ Y be sets of representatives of elements of ¯X and. ¯Y respectively. Let ¯g ∈ ¯Gn be the homomorphic image of g ∈ Gn, then ¯g =.

  3. Airborne Differential Doppler Weather Radar

    Science.gov (United States)

    Meneghini, R.; Bidwell, S.; Liao, L.; Rincon, R.; Heymsfield, G.; Hildebrand, Peter H. (Technical Monitor)

    2001-01-01

    The Precipitation Radar aboard the Tropical Rain Measuring Mission (TRMM) Satellite has shown the potential for spaceborne sensing of snow and rain by means of an incoherent pulsed radar operating at 13.8 GHz. The primary advantage of radar relative to passive instruments arises from the fact that the radar can image the 3-dimensional structure of storms. As a consequence, the radar data can be used to determine the vertical rain structure, rain type (convective/stratiform) effective storm height, and location of the melting layer. The radar, moreover, can be used to detect snow and improve the estimation of rain rate over land. To move toward spaceborne weather radars that can be deployed routinely as part of an instrument set consisting of passive and active sensors will require the development of less expensive, lighter-weight radars that consume less power. At the same time, the addition of a second frequency and an upgrade to Doppler capability are features that are needed to retrieve information on the characteristics of the drop size distribution, vertical air motion and storm dynamics. One approach to the problem is to use a single broad-band transmitter-receiver and antenna where two narrow-band frequencies are spaced apart by 5% to 10% of the center frequency. Use of Ka-band frequencies (26.5 GHz - 40 GHz) affords two advantages: adequate spatial resolution can be attained with a relatively small antenna and the differential reflectivity and mean Doppler signals are directly related to the median mass diameter of the snow and raindrop size distributions. The differential mean Doppler signal has the additional property that this quantity depends only on that part of the radial speed of the hydrometeors that is drop-size dependent. In principle, the mean and differential mean Doppler from a near-nadir viewing radar can be used to retrieve vertical air motion as well as the total mean radial velocity. In the paper, we present theoretical calculations for the

  4. Cavity-ring-down Doppler-broadening primary thermometry

    Science.gov (United States)

    Gotti, Riccardo; Moretti, Luigi; Gatti, Davide; Castrillo, Antonio; Galzerano, Gianluca; Laporta, Paolo; Gianfrani, Livio; Marangoni, Marco

    2018-01-01

    A step forward in Doppler-broadening thermometry is demonstrated using a comb-assisted cavity-ring-down spectroscopic approach applied to an isolated near-infrared line of carbon dioxide at thermodynamic equilibrium. Specifically, the line-shape of the Pe(12 ) line of the (30012 )←(00001 ) band of C O2 at 1.578 µm is accurately measured and its Doppler width extracted from a refined multispectrum fitting procedure accounting for the speed dependence of the relaxation rates, which were found to play a role even at the very low pressures explored, from 1 to 7 Pa. The thermodynamic gas temperature is retrieved with relative uncertainties of 8 ×10-6 (type A) and 11 ×10-6 (type B), which ranks the system at the first place among optical methods. Thanks to a measurement time of only ≈5 h , the technique represents a promising pathway toward the optical determination of the thermodynamic temperature with a global uncertainty at the 10-6 level.

  5. Estimating the Doppler centroid of SAR data

    DEFF Research Database (Denmark)

    Madsen, Søren Nørvang

    1989-01-01

    After reviewing frequency-domain techniques for estimating the Doppler centroid of synthetic-aperture radar (SAR) data, the author describes a time-domain method and highlights its advantages. In particular, a nonlinear time-domain algorithm called the sign-Doppler estimator (SDE) is shown to hav...

  6. Radar Doppler Processing with Nonuniform Sampling.

    Energy Technology Data Exchange (ETDEWEB)

    Doerry, Armin W. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-07-01

    Conventional signal processing to estimate radar Doppler frequency often assumes uniform pulse/sample spacing. This is for the convenience of t he processing. More recent performance enhancements in processor capability allow optimally processing nonuniform pulse/sample spacing, thereby overcoming some of the baggage that attends uniform sampling, such as Doppler ambiguity and SNR losses due to sidelobe control measures.

  7. Residue processing

    Energy Technology Data Exchange (ETDEWEB)

    Gieg, W.; Rank, V.

    1942-10-15

    In the first stage of coal hydrogenation, the liquid phase, light and heavy oils were produced; the latter containing the nonliquefied parts of the coal, the coal ash, and the catalyst substances. It was the problem of residue processing to extract from these so-called let-down oils that which could be used as pasting oils for the coal. The object was to obtain a maximum oil extraction and a complete removal of the solids, because of the latter were returned to the process they would needlessly burden the reaction space. Separation of solids in residue processing could be accomplished by filtration, centrifugation, extraction, distillation, or low-temperature carbonization (L.T.C.). Filtration or centrifugation was most suitable since a maximum oil yield could be expected from it, since only a small portion of the let-down oil contained in the filtration or centrifugation residue had to be thermally treated. The most satisfactory centrifuge at this time was the Laval, which delivered liquid centrifuge residue and centrifuge oil continuously. By comparison, the semi-continuous centrifuges delivered plastic residues which were difficult to handle. Various apparatus such as the spiral screw kiln and the ball kiln were used for low-temperature carbonization of centrifuge residues. Both were based on the idea of carbonization in thin layers. Efforts were also being made to produce electrode carbon and briquette binder as by-products of the liquid coal phase.

  8. Inverse Doppler Effects in Broadband Acoustic Metamaterials.

    Science.gov (United States)

    Zhai, S L; Zhao, X P; Liu, S; Shen, F L; Li, L L; Luo, C R

    2016-08-31

    The Doppler effect refers to the change in frequency of a wave source as a consequence of the relative motion between the source and an observer. Veselago theoretically predicted that materials with negative refractions can induce inverse Doppler effects. With the development of metamaterials, inverse Doppler effects have been extensively investigated. However, the ideal material parameters prescribed by these metamaterial design approaches are complex and also challenging to obtain experimentally. Here, we demonstrated a method of designing and experimentally characterising arbitrary broadband acoustic metamaterials. These omni-directional, double-negative, acoustic metamaterials are constructed with 'flute-like' acoustic meta-cluster sets with seven double meta-molecules; these metamaterials also overcome the limitations of broadband negative bulk modulus and mass density to provide a region of negative refraction and inverse Doppler effects. It was also shown that inverse Doppler effects can be detected in a flute, which has been popular for thousands of years in Asia and Europe.

  9. Color doppler sonography in thickened gallbladder wall

    Energy Technology Data Exchange (ETDEWEB)

    Han, Sang Suk; Choi, Seok Jin; Seo, Chang Hae; Eun, Choong Ki [Inje Univ. College of Medicine, Kimhae (Korea, Republic of)

    1996-11-01

    The thickening of the gallbladder wall is a valuable finding for the diagnosis of cholecystitis, but may be seen in non-cholecystic disease as well as in acute or chronic cholecystitis. The purpose of this study is to determine the value of color Doppler sonography in differentiating the causes of thickened gallbladder wall. Ninety eight patients with thickened gallbladder wall(more than 3mm) which was not due to gallbladder cancer were prospectively evaluated with color Doppler sonography. Sixty-six cases, confirmed by pathologic reports and clinical records, were analyzed for correlation between thickened gallbladder wall and color flow signal according to the underlying causes. Of the 66 patients, 28 cases were cholecystitis and 38 cases had non-cholecystic causes such as liver cirrhosis, ascites, hepatitis, pancreatitis, renal failure, and hypoalbuminemia. Of the 28 patients with cholecystitis(12 acute, 16 chronic), 23(82%) had color Doppler flow signals in the thickened gallbladder wall. Of the 38 patients with non-cholecystic causes, eight(21%) had color Doppler flow signals. There was a statistically significant difference of color Doppler flow signals between the cholecystitis and non-cholecystic groups(p=0.0001). No significant difference of color Doppler flow signals was found between cases of acute and chronic cholecystitis. Of the 23 patients with color Doppler flow signals in 28 cases of cholecystitis, 18(78.3%) showed a linear pattern and five(21.7%) showed a spotty pattern. Of the eight patients with color Doppler flow signals in the 38 non-cholecystic cases, four(50%) showed a linear pattern and four(50%) showed a spotty pattern. In cholecystitis, a linear color Doppler flow signal pattern is a much more frequent finding than a spotty pattern. Color Doppler sonography is a useful and adequate method for determining whether a thickened gallbladder wall is the result of cholecystitis or has non-cholecystic causes.

  10. BAM: Bayesian AMHG-Manning Inference of Discharge Using Remotely Sensed Stream Width, Slope, and Height

    Science.gov (United States)

    Hagemann, M. W.; Gleason, C. J.; Durand, M. T.

    2017-11-01

    The forthcoming Surface Water and Ocean Topography (SWOT) NASA satellite mission will measure water surface width, height, and slope of major rivers worldwide. The resulting data could provide an unprecedented account of river discharge at continental scales, but reliable methods need to be identified prior to launch. Here we present a novel algorithm for discharge estimation from only remotely sensed stream width, slope, and height at multiple locations along a mass-conserved river segment. The algorithm, termed the Bayesian AMHG-Manning (BAM) algorithm, implements a Bayesian formulation of streamflow uncertainty using a combination of Manning's equation and at-many-stations hydraulic geometry (AMHG). Bayesian methods provide a statistically defensible approach to generating discharge estimates in a physically underconstrained system but rely on prior distributions that quantify the a priori uncertainty of unknown quantities including discharge and hydraulic equation parameters. These were obtained from literature-reported values and from a USGS data set of acoustic Doppler current profiler (ADCP) measurements at USGS stream gauges. A data set of simulated widths, slopes, and heights from 19 rivers was used to evaluate the algorithms using a set of performance metrics. Results across the 19 rivers indicate an improvement in performance of BAM over previously tested methods and highlight a path forward in solving discharge estimation using solely satellite remote sensing.

  11. Line width of Josephson flux flow oscillators

    DEFF Research Database (Denmark)

    Koshelets, V.P.; Dmitriev, P.N.; Sobolev, A.S.

    2002-01-01

    spacing of about 20 nV and extremely low differential resistance, recently observed in the IVC of the standard rectangular geometry. The obtained results have been compared with existing theories and FFO models in order to understand and possibly eliminate excess noise in the FFO. The intrinsic line width...... increases considerably at voltages above the boundary voltage because of the abrupt increase of the internal damping due to Josephson self-coupling. The influence of FFO parameters, in particular the differential resistances associated both with the bias current and with the applied magnetic field...

  12. Justification of Requirements to the Operating Area of the Doppler Short-Range Location System

    Directory of Open Access Journals (Sweden)

    V. A. Kovrigin

    2014-01-01

    Full Text Available The article considers some issues of matching the operating area of the Doppler shortrange location system (SRLS with the destructing area of a fragmentation warhead in a wide range of applicability with no information about the angular position of the target.When action is against the low altitude aerial targets at the sea surface background Doppler SRLS are often used to provide frequency selection of a target owing to differences in the spectral characteristics of the required signal and interferences. However, Doppler systems have an inherent disadvantage i.e. the inability to estimate the angular position of the target wit respect to the SRLS.Consequently, an arising problem to ensure the effectiveness of the combat unit, which includes the guidance system, Doppler SRLS, and fragmentation warhead is of significant practical use, when acting against the low altitude aerial targets in a wide range of encounter environment with a lack of information about the angular position of the target. The article considers a practical method for ensuring the effectiveness of the combat unit by selecting the width of the destructing elements separation angle and its orientation in space.An approximate method of geometric matching the scopes of warhead and SRLS based on computer aided numerical calculation is used. With the geometric approach to the efficiency estimation in any desired angular position of the target, Doppler SRLS should form a command to burst the warhead ensuring the straddling of the target by the field of destructing elements in an arbitrary predetermined point of conditions.Algorithms of the warhead and SRLS functioning are developed and utilized as applied programs. A Doppler SRLS model is proposed. The SRLS is integrated with semi-active Doppler homing head in case there is small-sized radar target. The article presents a mathematical description of the fragmentation warhead for relatively small misses, ignoring the air resistance

  13. Bubble-Induced Color Doppler Feedback for Histotripsy Tissue Fractionation.

    Science.gov (United States)

    Miller, Ryan M; Zhang, Xi; Maxwell, Adam D; Cain, Charles A; Xu, Zhen

    2016-03-01

    Histotripsy therapy produces cavitating bubble clouds to increasingly fractionate and eventually liquefy tissue using high-intensity ultrasound pulses. Following cavitation generated by each pulse, coherent motion of the cavitation residual nuclei can be detected using metrics formed from ultrasound color Doppler acquisitions. In this paper, three experiments were performed to investigate the characteristics of this motion as real-time feedback on histotripsy tissue fractionation. In the first experiment, bubble-induced color Doppler (BCD) and particle image velocimetry (PIV) analysis monitored the residual cavitation nuclei in the treatment region in an agarose tissue phantom treated with two-cycle histotripsy pulses at [Formula: see text] using a 500-kHz transducer. Both BCD and PIV results showed brief chaotic motion of the residual nuclei followed by coherent motion first moving away from the transducer and then rebounding back. Velocity measurements from both PIV and BCD agreed well, showing a monotonic increase in rebound time up to a saturation point for increased therapy dose. In a second experiment, a thin layer of red blood cells (RBC) was added to the phantom to allow quantification of the fractionation of the RBC layer to compare with BCD metrics. A strong linear correlation was observed between the fractionation level and the time to BCD peak rebound velocity over histotripsy treatment. Finally, the correlation between BCD feedback and histotripsy tissue fractionation was validated in ex vivo porcine liver evaluated histologically. BCD metrics showed strong linear correlation with fractionation progression, suggesting that BCD provides useful quantitative real-time feedback on histotripsy treatment progression.

  14. Patient-exposure data for doppler ultrasound

    International Nuclear Information System (INIS)

    Stewart, H.F.; Silvis, P.X.; Smith, S.W.

    1986-01-01

    In recent years ultrasound imaging and Doppler blood flow measurements have become important tools for use in diagnostic medicine. Commercial pulse-echo imaging equipment was first introduced into commerce in 1963. The first commercial continuous wave Doppler unit was introduced to the marketplace in 1966. As equipment improved and applications developed, the industry experienced rapid growth in the 1970s. One of the more recent growth areas in the application of diagnostic ultrasound has been the use of pulsed Doppler equipment for cardiac applications. Prior to 1976, some continuous wave Doppler ultrasound was used for cardiovascular diagnosis. However, only a single manufacturer marketed a pulsed Doppler clinical instrument for cardiac or peripheral vascular diagnosis. Currently, many continuous wave and pulsed Doppler instruments are commercially available for both peripheral vascular and cardiac diagnosis. This chapter (1) briefly reviews current safety guidelines, regulations, and recommendations for diagnostic ultrasound; (2) discusses the patient-exposure intensities associated with Doppler ultrasound medical equipment and compare these levels of exposure with intensities from other medical ultrasound devices; and (3) considers some of the current information as it relates to the safety of diagnostic ultrasound

  15. Pulse width modulation inverter with battery charger

    Science.gov (United States)

    Slicker, James M. (Inventor)

    1985-01-01

    An inverter is connected between a source of DC power and a three-phase AC induction motor, and a microprocessor-based circuit controls the inverter using pulse width modulation techniques. In the disclosed method of pulse width modulation, both edges of each pulse of a carrier pulse train are equally modulated by a time proportional to sin .theta., where .theta. is the angular displacement of the pulse center at the motor stator frequency from a fixed reference point on the carrier waveform. The carrier waveform frequency is a multiple of the motor stator frequency. The modulated pulse train is then applied to each of the motor phase inputs with respective phase shifts of 120.degree. at the stator frequency. Switching control commands for electronic switches in the inverter are stored in a random access memory (RAM) and the locations of the RAM are successively read out in a cyclic manner, each bit of a given RAM location controlling a respective phase input of the motor. The DC power source preferably comprises rechargeable batteries and all but one of the electronic switches in the inverter can be disabled, the remaining electronic switch being part of a flyback DC-DC converter circuit for recharging the battery.

  16. Transrectal ultrasound color Doppler in the evaluation of recurrence of anal canal cancer

    International Nuclear Information System (INIS)

    Drudi, Francesco M.; Giovagnorio, Francesco; Raffetto, Nicola; Ricci, Paolo; Cascone, Fiammetta; Santarelli, Mario; Trippa, Francesca; Passariello, Roberto

    2003-01-01

    Objective: aim was to obtain elements for a differential diagnosis between post-radiation fibrosis and residual tumor or local relapse in anal canal cancer through detection of presence/absence of intralesional blood flow. Transrectal ultrasound and color Doppler were compared. Methods: 43 patients underwent transrectal ultrasound sonography and color Doppler before and after therapy to assess intralesional blood flow and flow pattern (spotty and linear signals). All diagnostic imaging results were compared to histological analysis. Specificity was submitted to statistical analysis using McNemar test. Results: before therapy 34 lesions (79%) showed color signal; no signal in 9 (21%), which were excluded from our analysis. Eighteen of the 34 patients considered, presented complete response to therapy, 14 partial response and two no response. After therapy, signal disappeared in 17 patients (94%); one false-positive (6%) presented spotty signals; 16 of 34 patients presented changed color signal. Color Doppler showed higher specificity than grey scale transrectal ultrasound in the differentiation of fibrosis from tumor. Response was confirmed by histological examination, considered gold standard. McNemar test demonstrated the significance of color Doppler (P<0.0001). Conclusion: color Doppler considerably increases transrectal ultrasound specificity in differentiating tumor relapse from fibrosis in anal canal cancer

  17. Doppler Velocity Signatures of Idealized Elliptical Vortices

    Directory of Open Access Journals (Sweden)

    Wen-Chau Lee

    2006-01-01

    Full Text Available Doppler radar observations have revealed a class of atmospheric vortices (tropical cyclones, tornadoes, dust devils that possess elliptical radar reflectivity signatures. One famous example is Typhoon Herb (1996 that maintained its elliptical reflectivity structure over a 40-hour period. Theoretical work and dual-Doppler analyses of observed tropical cyclones have suggested two physical mechanisms that can explain the formation of two types of elliptical vortices observed in nature, namely, the combination of a circular vortex with either a wavenumber two vortex Rossby wave or a deformation field. The characteristics of these two types of elliptical vortices and their corresponding Doppler velocity signatures have not been previously examined.

  18. Stochastic Mixed-Effects Parameters Bertalanffy Process, with Applications to Tree Crown Width Modeling

    Directory of Open Access Journals (Sweden)

    Petras Rupšys

    2015-01-01

    Full Text Available A stochastic modeling approach based on the Bertalanffy law gained interest due to its ability to produce more accurate results than the deterministic approaches. We examine tree crown width dynamic with the Bertalanffy type stochastic differential equation (SDE and mixed-effects parameters. In this study, we demonstrate how this simple model can be used to calculate predictions of crown width. We propose a parameter estimation method and computational guidelines. The primary goal of the study was to estimate the parameters by considering discrete sampling of the diameter at breast height and crown width and by using maximum likelihood procedure. Performance statistics for the crown width equation include statistical indexes and analysis of residuals. We use data provided by the Lithuanian National Forest Inventory from Scots pine trees to illustrate issues of our modeling technique. Comparison of the predicted crown width values of mixed-effects parameters model with those obtained using fixed-effects parameters model demonstrates the predictive power of the stochastic differential equations model with mixed-effects parameters. All results were implemented in a symbolic algebra system MAPLE.

  19. Marine Tar Residues: a Review.

    Science.gov (United States)

    Warnock, April M; Hagen, Scott C; Passeri, Davina L

    Marine tar residues originate from natural and anthropogenic oil releases into the ocean environment and are formed after liquid petroleum is transformed by weathering, sedimentation, and other processes. Tar balls, tar mats, and tar patties are common examples of marine tar residues and can range in size from millimeters in diameter (tar balls) to several meters in length and width (tar mats). These residues can remain in the ocean environment indefinitely, decomposing or becoming buried in the sea floor. However, in many cases, they are transported ashore via currents and waves where they pose a concern to coastal recreation activities, the seafood industry and may have negative effects on wildlife. This review summarizes the current state of knowledge on marine tar residue formation, transport, degradation, and distribution. Methods of detection and removal of marine tar residues and their possible ecological effects are discussed, in addition to topics of marine tar research that warrant further investigation. Emphasis is placed on benthic tar residues, with a focus on the remnants of the Deepwater Horizon oil spill in particular, which are still affecting the northern Gulf of Mexico shores years after the leaking submarine well was capped.

  20. Residual risk

    African Journals Online (AJOL)

    ing the residual risk of transmission of HIV by blood transfusion. An epidemiological approach assumed that all HIV infections detected serologically in first-time donors were pre-existing or prevalent infections, and that all infections detected in repeat blood donors were new or incident infections. During 1986 - 1987,0,012%.

  1. Doppler spectroscopy of hydrogen Balmer lines in a hollow cathode glow discharge in ammonia and argon-ammonia mixture

    International Nuclear Information System (INIS)

    Sisovic, N. M.; Konjevic, N.

    2008-01-01

    The results of Doppler spectroscopy of hydrogen Balmer lines from a stainless steel (SS) and copper (Cu) hollow cathode (HC) glow discharge in ammonia and argon-ammonia mixture are reported. The experimental profiles in ammonia discharge are fitted well by superposing three Gaussian profiles. The half widths, in energy units, of narrow and medium Gaussians are in the ranges 0.3-0.4 eV and 3-4 eV, respectively, for both hollow cathodes what is expected on the basis of earlier electron beam→NH 3 experiments. The half widths of the largest Gaussian in ammonia are 46 and 55 eV for SS and Cu HC, respectively. In argon-ammonia discharge, three Gaussians are also required to fit experimental profiles. While half widths of narrow and medium Gaussians are similar to those in ammonia, the half widths of the largest Gaussians are 35 and 42 eV for SS and Cu HC, respectively. The half widths of the largest Gaussians in ammonia and in argon-ammonia mixture indicate the presence of excessive Doppler broadening.

  2. Electromagnetically induced transparency in thermal Rydberg atoms: superatom model with finite Doppler broadening

    Science.gov (United States)

    Bai, Si-Yin; Bao, Qian-Qian; Tian, Xue-Dong; Liu, Yi-Mou; Wu, Jin-Hui

    2018-04-01

    We study the steady optical responses of a cold atomic ensemble driven into the three-level ladder configuration involving a Rydberg state at finite temperatures. By improving the superatom model with thermal movement included, we calculate relevant atomic coherence effects and find that the residual Doppler broadening at the mK-K temperatures will weaken the nonclassical properties of transmitted probe photons. Furthermore, propagation directions of the probe and coupling fields have a great influence on various properties related to electromagnetically induced transparency. That is, the residual Doppler effect is more destructive to relevant atomic coherence effects in the co-propagation case but can be partially eliminated in the counter-propagation case.

  3. Lake Basin Fetch and Maximum Length/Width

    Data.gov (United States)

    Minnesota Department of Natural Resources — Linear features representing the Fetch, Maximum Length and Maximum Width of a lake basin. Fetch, maximum length and average width are calcuated from the lake polygon...

  4. Direct measurement of the W boson width

    Energy Technology Data Exchange (ETDEWEB)

    Abazov, V.M.; /Dubna, JINR; Abbott, B.; /Oklahoma U.; Abolins, M.; /Michigan State U.; Acharya, B.S.; /Tata Inst.; Adams, M.; /Illinois U., Chicago; Adams, T.; /Florida State U.; Aguilo, E.; /Alberta U. /Simon Fraser U. /McGill U.; Ahsan, M.; /Kansas State U.; Alexeev, G.D.; /Dubna, JINR; Alkhazov, G.; /St. Petersburg, INP; Alton, A.; /Michigan U. /Northeastern U.

    2009-09-01

    We present a direct measurement of the width of the W boson using the shape of the transverse mass distribution of W {yields} e{nu} candidates selected in 1 fb{sup -1} of data collected with the D0 detector at the Fermilab Tevatron collider in p{bar p} collisions at {radical}s = 1.96 TeV. We use the same methods and data sample that were used for our recently published W boson mass measurement, except for the modeling of the recoil, which is done with a new method based on a recoil library. Our result, 2.028 {+-} 0.072 GeV, is in agreement with the predictions of the standard model and is the most precise direct measurement result from a single experiment to date.

  5. Uncovering the CH-53E Doppler Myth

    National Research Council Canada - National Science Library

    Lamigo, Dwaine

    2008-01-01

    The CH-53E's Helicopter Night Vision System's (HNVS) doppler generated cuing ability is a valuable asset that can enhance the pilot's situational awareness and mitigate spatial disorientation in low-level maneuvers...

  6. Doppler coefficient measurements in Zebra Core 5

    International Nuclear Information System (INIS)

    Baker, A.R.; Wheeler, R.C.

    1965-11-01

    Measurements using a central hot loop in Zebra Core 5 are described. Results are given for the Doppler coefficients found in a number of assemblies with PuO 2 and 16% PuO 2 /84% depleted UO 2 pins, loaded with different combinations of steel, sodium or void pins. The mixed oxide results are in general about 20% more negative than was calculated using the FD2 data set, but agreement is good if the plutonium contributions in the calculations are omitted. The small positive Doppler coefficient calculated for Pu239 was not observed, and two measurements indicated instead a small negative effect. The Doppler effect in the mixed oxide systems was found to vary approximately as 1/T. The results from the empty loop and non-fissile assemblies indicate either a small negative Doppler effect in steel or alternatively the presence of an unexplained expansion effect. (author)

  7. Moving Sources: Doppler Beats and Mach Cones

    Science.gov (United States)

    Gluck, Paul

    2005-09-01

    This paper describes two experiments involving moving sources. The first one is a class activity for observing beats in a Doppler setup; the second one describes how to observe the transition from "subsonic" to "supersonic" waves in a ripple tank.

  8. Color doppler and power doppler ultrasonography in renal transplant recipients with cytomegalovirus infection

    International Nuclear Information System (INIS)

    Wan Guangsheng; Chen Xionghui; Li Meidi; Shao Zheying; Peng Shubai

    2003-01-01

    Objective: To investigate the features of color Doppler and Doppler ultrasonography of transplanted kidneys in patients with cytomegalovirus infections. Methods: Color Doppler and Power Doppler ultrasonography was used to examine transplanted kidneys in 36 recipients with cytomegalovirus infection. The blood flow area ratios (BFAR), the volumes, the resistive indexes (RI), the peak flow velocities in parenchymal arteries (Vmax) were measured and compared with no complication (normal) cases. Results: BFAR was lower in patients with cytomegalovirus infection than that in no complication (normal) cases (P 0.05). Conclusions: The blood flows of transplanted kidneys were reduced in patients with cytomegalovirus infection. To monitor BFAR of transplanted kidneys was contributed to evaluate management effect

  9. with Ultrasound Color Doppler Imaging

    Directory of Open Access Journals (Sweden)

    Shin Takayama

    2012-01-01

    Full Text Available Color Doppler imaging (CDI can be used to noninvasively create images of human blood vessels and quantitatively evaluate blood flow in real-time. The purpose of this study was to assess the effects of acupuncture on the blood flow of the peripheral, mesenteric, and retrobulbar arteries by CDI. Statistical significance was defined as P values less than 0.05. Blood flow in the radial and brachial arteries was significantly lower during needle stimulation on LR3 than before in healthy volunteers, but was significantly higher after needle stimulation than before. LR3 stimulation also resulted in a significant decrease in the vascular resistance of the short posterior ciliary artery and no significant change of blood flow through the superior mesenteric artery (SMA during acupuncture. In contrast, ST36 stimulation resulted in a significant increase in blood flow through the SMA and no significant change in the vascular resistance of the retrobulbar arteries. Additionally, acupuncture at previously determined acupoints in patients with open-angle glaucoma led to a significant reduction in the vascular resistance of the central retinal artery and short posterior ciliary artery. Our results suggest that acupuncture can affect blood flow of the peripheral, mesenteric, and retrobulbar arteries, and CDI can be useful to evaluate hemodynamic changes by acupuncture.

  10. Applications of Doppler in the first trimester

    International Nuclear Information System (INIS)

    Taylor, K.J.W.; Ramirez, B.; Grannum, P.

    1986-01-01

    Fifty patients have been studied by duplex Doppler US imaging in the first trimester. In normal gestations, luteal flow, characterized by a low pulsatility index (PI), can be seen in at least one ovary. Failure to detect luteal flow indicates a nonviable pregnancy. Six ectopic pregnancies demonstrated luteal flow and extrauterine heartbeat, detected by Doppler US. High PI values in the uterine artery are seen in the first trimester. Low PI values in the uterine arteries were found in patients with trophoblastic disease

  11. Estimating discharge using multi-level velocity data from acoustic doppler instruments

    DEFF Research Database (Denmark)

    Poulsen, Jane Bang; Rasmussen, Keld Rømer; Ovesen, Niels Bering

    it records the stage. The monthly control measurements made by the water authority office are made with an ADCP-instrument (Streampro, acoustic Doppler current profiler) which is pulled across the stream next to the in situ Doppler instruments. As part of the present project supplementary ADCP-data have been......In the majority of Danish streams, weed growth affects the effective stream width and bed roughness thus imposes temporal variations on the stage-discharge relationship. Small stream-gradients and firm ecology based restrictions prevent that hydraulic structures are made at the discharge stations...... and thus remove or limit such influences. Hence, estimation of the hydrograph is based on continuous stream gauging combined with monthly control measurements of discharge and assuming linear variation of bed roughness between the monthly measurements. As a result, any non-linear drift in weed density...

  12. Doppler and time-travel broadening in ICR plasma isotope separation

    International Nuclear Information System (INIS)

    Karchevskii, A.I.; Potanin, E.P.

    1994-01-01

    Isotopically-selective ion-cyclotron resonance (ICR) heating is one of the most promising plasma isotope separation methods. The separation degree of ICR separation in a plasma depends on the resonance heating selectivity. The selectivity is due to the isotopically-adjacent accelerated ions resonance curve overlapping and therefore, is determined by the width of the resonance curves. In the case of a collisionless plasma in an ideal homogeneous longitudinal magnetic field, the line broadening is mainly determined by Doppler and time-travel effects. These effects differ in nature, and one has some difficulties in distinguishing them when interpreting the resonance curves because both broadenings depend on ion axial velocities. We consider the simplest case: the extrenal heating alternating electric field does not depend on the axial coordinate (the wave number γ = 0). Hence, in this case the Doppler effect does not occur

  13. Characterizing graphs of maximum matching width at most 2

    DEFF Research Database (Denmark)

    Jeong, Jisu; Ok, Seongmin; Suh, Geewon

    2017-01-01

    The maximum matching width is a width-parameter that is de ned on a branch-decomposition over the vertex set of a graph. The size of a maximum matching in the bipartite graph is used as a cut-function. In this paper, we characterize the graphs of maximum matching width at most 2 using the minor...

  14. GAP WIDTH STUDY IN LASER BUTT-WELDING

    DEFF Research Database (Denmark)

    Gong, Hui; Olsen, Flemming Ove

    In this paper the maximum allowable gap width in laser butt-welding is intensively studied. The gap width study (GWS) is performed on the material of SST of W1.4401 (AISI 316) under various welding conditions, which are the gap width : 0.00-0.50 mm, the welding speed : 0.5-2.0 m/min, the laser...

  15. Residual basins

    International Nuclear Information System (INIS)

    D'Elboux, C.V.; Paiva, I.B.

    1980-01-01

    Exploration for uranium carried out over a major portion of the Rio Grande do Sul Shield has revealed a number of small residual basins developed along glacially eroded channels of pre-Permian age. Mineralization of uranium occurs in two distinct sedimentary units. The lower unit consists of rhythmites overlain by a sequence of black shales, siltstones and coal seams, while the upper one is dominated by sandstones of probable fluvial origin. (Author) [pt

  16. Global synchronization of parallel processors using clock pulse width modulation

    Science.gov (United States)

    Chen, Dong; Ellavsky, Matthew R.; Franke, Ross L.; Gara, Alan; Gooding, Thomas M.; Haring, Rudolf A.; Jeanson, Mark J.; Kopcsay, Gerard V.; Liebsch, Thomas A.; Littrell, Daniel; Ohmacht, Martin; Reed, Don D.; Schenck, Brandon E.; Swetz, Richard A.

    2013-04-02

    A circuit generates a global clock signal with a pulse width modification to synchronize processors in a parallel computing system. The circuit may include a hardware module and a clock splitter. The hardware module may generate a clock signal and performs a pulse width modification on the clock signal. The pulse width modification changes a pulse width within a clock period in the clock signal. The clock splitter may distribute the pulse width modified clock signal to a plurality of processors in the parallel computing system.

  17. Narrow-width mechanism of a=5 Ξ-state

    International Nuclear Information System (INIS)

    Kumagai-Fuse, I.; Akaishi, Y.

    1995-04-01

    Narrow-width mechanism of ≡ 5 H is discussed by calculating conversion widths to all its possible decay channels. Since the conversion processes have small reaction Q values, the three- and four- body decays are strongly suppressed owing to small phase volumes available. Decay widths to the two-body channels are significantly reduced by the distortion of emitted-particle waves. This mechanism brings about a narrow width of ≡ 5 H. The total width is estimated to be 0.87 MeV, in which the largest contribution comes from the decay into the Λ 4 H * +Λ channel. (author)

  18. Beam-width spreading of vortex beams in free space

    Science.gov (United States)

    Wang, Weiwei; Li, Jinhong; Duan, Meiling

    2018-01-01

    Based on the extended Huygens-Fresnel principle and the definition of second-order moments of the Wigner distribution function, the analytical expression for the beam-width spreading of Gaussian Schell-model (GSM) vortex beams in free space are derived, and used to study the influence of beam parameters on the beam-width spreading of GSM vortex beams. With the increment of the propagation distance, the beam-width spreading of GSM vortex beams will increase; the bigger the topological charge, spatial correlation length, wavelength and waist width are, the smaller the beam-width spreading is.

  19. Doppler Broadening Thermometry Based on Cavity Ring-Down Spectroscopy

    Science.gov (United States)

    Hu, Shui-Ming; Cheng, Cunfeng; Wang, Jin; Tan, Yan; Sun, Yu Robert; Liu, An-Wen; Zhang, Jin-Tao

    2014-06-01

    A Doppler broadening thermometry is implemented using a laser-locked cavity ring-down spectrometer [1,2] combined with a temperature-stabilized sample cell. The temperature fluctuation of the gas sample cell is kept below 1 mK for hours. The probing laser is frequency locked at a longitudinal mode of a Fabry-Pérot interferometer made of ultra-low-expansion glass, and the spectral scan is implemented by scanning the sideband produced by an electro-optic modulator. As a result, a kHz precision has been maintained during the measurement of the spectrum of 10 GHz wide. A ro-vibrational line of C_2H_2 is measured at sample pressures of a few Pa. Using a pair of mirrors with a reflectivity of 0.99997 at 787 nm, we are able to detect absorption line profiles with a signal-to-noise ratio of 10^5. Fitting of the recorded spectra allows us to determine the Doppler width with a statistical uncertainty of 10 ppm. Further improvements on the experimental reproducibility and investigations on the collision effects will probably lead to an optical determination of the Boltzmann constant with an uncertainty of a few ppm. H. Pan, C.-F. Cheng, Y. R. Sun, B. Gao, A.-W. Liu, S.-M. Hu, ``Laser-locked, continuously tunable high resolution cavity ring-down spectrometer," Rev. Sci. Instrum. 82, 103110 (2011) Y. R. Sun, H. Pan, C.-F. Cheng, A.-W. Liu, J.-T. Zhang, S.-M. Hu, ``Application of cavity ring-down spectroscopy to the Boltzmann constant determination," Opt. Express, 19, 19993 (2011)

  20. Ultrasonography with color Doppler and power Doppler in the diagnosis of periapical lesions

    Directory of Open Access Journals (Sweden)

    Sumit Goel

    2011-01-01

    Full Text Available Aim: To evaluate the efficacy of ultrasonography (USG with color Doppler and power Doppler applications over conventional radiography in the diagnosis of periapical lesions. Materials and Methods: Thirty patients having inflammatory periapical lesions of the maxillary or mandibular anterior teeth and requiring endodontic surgery were selected for inclusion in this study. All patients consented to participate in the study. We used conventional periapical radiographs as well as USG with color Doppler and power Doppler for the diagnosis of these lesions. Their diagnostic performances were compared against histopathologic examination. All data were compared and statistically analyzed. Results: USG examination with color Doppler and power Doppler identified 29 (19 cysts and 10 granulomas of 30 periapical lesions accurately, with a sensitivity of 100% for cysts and 90.91% for granulomas and a specificity of 90.91% for cysts and 100% for granulomas. In comparison, conventional intraoral radiography identified only 21 lesions (sensitivity of 78.9% for cysts and 45.4% for granulomas and specificity of 45.4% for cysts and 78.9% for granulomas. There was definite correlation between the echotexture of the lesions and the histopathological features except in one case. Conclusions: USG imaging with color Doppler and power Doppler is superior to conventional intraoral radiographic methods for diagnosing the nature of periapical lesions in the anterior jaws. This study reveals the potential of USG examination in the study of other jaw lesions.

  1. Ultrasonography with color Doppler and power Doppler in the diagnosis of periapical lesions

    International Nuclear Information System (INIS)

    Goel, Sumit; Nagendrareddy, Suma Gundareddy; Raju, Manthena Srinivasa; Krishnojirao, Dayashankara Rao Jingade; Rastogi, Rajul; Mohan, Ravi Prakash Sasankoti; Gupta, Swati

    2011-01-01

    To evaluate the efficacy of ultrasonography (USG) with color Doppler and power Doppler applications over conventional radiography in the diagnosis of periapical lesions. Thirty patients having inflammatory periapical lesions of the maxillary or mandibular anterior teeth and requiring endodontic surgery were selected for inclusion in this study. All patients consented to participate in the study. We used conventional periapical radiographs as well as USG with color Doppler and power Doppler for the diagnosis of these lesions. Their diagnostic performances were compared against histopathologic examination. All data were compared and statistically analyzed. USG examination with color Doppler and power Doppler identified 29 (19 cysts and 10 granulomas) of 30 periapical lesions accurately, with a sensitivity of 100% for cysts and 90.91% for granulomas and a specificity of 90.91% for cysts and 100% for granulomas. In comparison, conventional intraoral radiography identified only 21 lesions (sensitivity of 78.9% for cysts and 45.4% for granulomas and specificity of 45.4% for cysts and 78.9% for granulomas). There was definite correlation between the echotexture of the lesions and the histopathological features except in one case. USG imaging with color Doppler and power Doppler is superior to conventional intraoral radiographic methods for diagnosing the nature of periapical lesions in the anterior jaws. This study reveals the potential of USG examination in the study of other jaw lesions

  2. Ultrasonography with color Doppler and power Doppler in the diagnosis of periapical lesions

    Science.gov (United States)

    Goel, Sumit; Nagendrareddy, Suma Gundareddy; Raju, Manthena Srinivasa; Krishnojirao, Dayashankara Rao Jingade; Rastogi, Rajul; Mohan, Ravi Prakash Sasankoti; Gupta, Swati

    2011-01-01

    Aim: To evaluate the efficacy of ultrasonography (USG) with color Doppler and power Doppler applications over conventional radiography in the diagnosis of periapical lesions. Materials and Methods: Thirty patients having inflammatory periapical lesions of the maxillary or mandibular anterior teeth and requiring endodontic surgery were selected for inclusion in this study. All patients consented to participate in the study. We used conventional periapical radiographs as well as USG with color Doppler and power Doppler for the diagnosis of these lesions. Their diagnostic performances were compared against histopathologic examination. All data were compared and statistically analyzed. Results: USG examination with color Doppler and power Doppler identified 29 (19 cysts and 10 granulomas) of 30 periapical lesions accurately, with a sensitivity of 100% for cysts and 90.91% for granulomas and a specificity of 90.91% for cysts and 100% for granulomas. In comparison, conventional intraoral radiography identified only 21 lesions (sensitivity of 78.9% for cysts and 45.4% for granulomas and specificity of 45.4% for cysts and 78.9% for granulomas). There was definite correlation between the echotexture of the lesions and the histopathological features except in one case. Conclusions: USG imaging with color Doppler and power Doppler is superior to conventional intraoral radiographic methods for diagnosing the nature of periapical lesions in the anterior jaws. This study reveals the potential of USG examination in the study of other jaw lesions. PMID:22223940

  3. Transient basilar artery occlusion monitored by transcranial color Doppler presenting with a spectacular shrinking deficit: a case report

    Directory of Open Access Journals (Sweden)

    Del Sette Massimo

    2010-01-01

    Full Text Available Abstract Introduction We describe the case of a 79-year-old Caucasian Italian woman with a transient basilar occlusion monitored by transcranial Doppler, with subsequent recanalization and clinical shrinking deficit. This is the first case of transient basilar occlusive disease diagnosed and monitored by transcranial Doppler. This case is important and needs to be reported because transient basilar occlusion may be easily diagnosed if transcranial Doppler is performed. Case presentation A 79-year-old woman affected by chronic atrial fibrillation and not treated with oral anticoagulants, cardioverted to sinus rhythm during a gastric endoscopy. She then showed a sudden-onset loss of consciousness, horizontal and vertical gaze palsy, tetraparesis and bilateral miosis and coma. Two hours later, the symptoms resolved quickly, leaving no residual neurologic deficits. Transcranial Doppler examination showed a dampened flow in the basilar artery in the emergency examination and a restored flow when the symptoms resolved. Conclusion This is the first case of transient basilar occlusive disease diagnosed and monitored by transcranial Doppler. We believe that transcranial Doppler should be performed in all cases of unexplained acute loss of consciousness, in particular, if associated with signs of brainstem dysfunctions.

  4. Editorial special issue on "Laser Doppler vibrometry"

    Science.gov (United States)

    Vanlanduit, Steve; Dirckx, Joris

    2017-12-01

    The invention of the laser in 1960 has opened up many opportunities in the field of measurement science and technology. Just a few years after the invention of the laser, a novel fluid flow measurement technique based on the Doppler effect was introduced: at that moment the laser Doppler anemometer or shortly LDA [1] was born. The technique enabled fluid velocity measurement by using the light of a He-Ne beam which was scattered by very small polystyrene spheres entrained in the fluid. Later on, in the late nineteen seventees it was recognized that the detection of the Doppler frequency shift that occurs when light is scattered by a moving surface can also be used to measure the vibration velocity of an object. The instrument to perform these vibration measurements was called the laser Doppler vibrometer or LDV [2]. In the last decades several technological advances were made in the field of laser Doppler vibrometry. The result is that nowadays, velocity measurements of fluids (using LDA) and vibrating objects (using LDV) are performed in many challenging applications in different fields (microelectronics, civil structures, biomedical engineering, material science, etc.).

  5. Development of the doppler electron velocimeter: theory.

    Energy Technology Data Exchange (ETDEWEB)

    Reu, Phillip L.

    2007-03-01

    Measurement of dynamic events at the nano-scale is currently impossible. This paper presents the theoretical underpinnings of a method for making these measurements using electron microscopes. Building on the work of Moellenstedt and Lichte who demonstrated Doppler shifting of an electron beam with a moving electron mirror, further work is proposed to perfect and utilize this concept in dynamic measurements. Specifically, using the concept of ''fringe-counting'' with the current principles of transmission electron holography, an extension of these methods to dynamic measurements is proposed. A presentation of the theory of Doppler electron wave shifting is given, starting from the development of the de Broglie wave, up through the equations describing interference effects and Doppler shifting in electron waves. A mathematical demonstration that Doppler shifting is identical to the conceptually easier to understand idea of counting moving fringes is given by analogy to optical interferometry. Finally, potential developmental experiments and uses of a Doppler electron microscope are discussed.

  6. Detection and discrimination of fauna in the aerosphere using Doppler weather surveillance radar.

    Science.gov (United States)

    Gauthreaux, Sidney A; Livingston, John W; Belser, Carroll G

    2008-07-01

    Organisms in the aerosphere have been detected by radar since its development in the 1940s. The national network of Doppler weather radars (WSR-88D) in the United States can readily detect birds, bats, and insects aloft. Level-II data from the radar contain information on the reflectivity and radial velocity of targets and on width of the spectrum (SD of radial velocities in a radar pulse volume). Information on reflectivity can be used to quantify density of organisms aloft and radial velocity can be used to discriminate different types of targets based on their air speeds. Spectral width can also provide some useful information when organisms with very different air speeds are aloft. Recent work with dual-polarization radar suggests that it may be useful for discriminating birds from insects in the aerosphere, but more development and biological validation are required.

  7. RESIDUAL RISK ASSESSMENTS - RESIDUAL RISK ...

    Science.gov (United States)

    This source category previously subjected to a technology-based standard will be examined to determine if health or ecological risks are significant enough to warrant further regulation for Coke Ovens. These assesments utilize existing models and data bases to examine the multi-media and multi-pollutant impacts of air toxics emissions on human health and the environment. Details on the assessment process and methodologies can be found in EPA's Residual Risk Report to Congress issued in March of 1999 (see web site). To assess the health risks imposed by air toxics emissions from Coke Ovens to determine if control technology standards previously established are adequately protecting public health.

  8. Diabetic Nephropathy : Evaluation with Doppler Ultrasonography

    Energy Technology Data Exchange (ETDEWEB)

    Sim, Jung Suk; Kim, Seung Hyup; Kang, Heung Sik; Park, Jae Hyung; Han, Man Chung [Seoul National University College of Medicine, Seoul (Korea, Republic of)

    1996-06-15

    To compare Doppler ultrasonography with laboratory tests in evaluation of diabetic nephropathy. Fifty-five patients (mean age = 60, M : F = 26 : 29) with diabetes mellitus underwent renal Doppler ultrasonography. Resistive indices were compared with degree of proteinuria, serum creatinine level, and creatinine clearance rate. Eighteen patients who showed no proteinuria or microscopic proteinuria had a mean resistive index (RI) of 0.72 (SD, 0.05), 16 patients with macroscopic proteinuria without nephrotic syndrome had a mean RI of 0.82 (SD, 0.13), and 21 patients with nephrotic syndrome had a mean RI of 0.90 (SD, 0.12). Renal RI correlated highly with serum creatinine level (r = 0.62) and creatinine clearance rate (r = -0.43). Renal Doppler ultrasonography provides a useful indication of renal function in diabetic nephropathy but cannot offer an advantage over conventional laboratory test

  9. Diabetic Nephropathy : Evaluation with Doppler Ultrasonography

    International Nuclear Information System (INIS)

    Sim, Jung Suk; Kim, Seung Hyup; Kang, Heung Sik; Park, Jae Hyung; Han, Man Chung

    1996-01-01

    To compare Doppler ultrasonography with laboratory tests in evaluation of diabetic nephropathy. Fifty-five patients (mean age = 60, M : F = 26 : 29) with diabetes mellitus underwent renal Doppler ultrasonography. Resistive indices were compared with degree of proteinuria, serum creatinine level, and creatinine clearance rate. Eighteen patients who showed no proteinuria or microscopic proteinuria had a mean resistive index (RI) of 0.72 (SD, 0.05), 16 patients with macroscopic proteinuria without nephrotic syndrome had a mean RI of 0.82 (SD, 0.13), and 21 patients with nephrotic syndrome had a mean RI of 0.90 (SD, 0.12). Renal RI correlated highly with serum creatinine level (r = 0.62) and creatinine clearance rate (r = -0.43). Renal Doppler ultrasonography provides a useful indication of renal function in diabetic nephropathy but cannot offer an advantage over conventional laboratory test

  10. Molecules cooled below the Doppler limit

    Science.gov (United States)

    Truppe, S.; Williams, H. J.; Hambach, M.; Caldwell, L.; Fitch, N. J.; Hinds, E. A.; Sauer, B. E.; Tarbutt, M. R.

    2017-12-01

    Magneto-optical trapping and sub-Doppler cooling have been essential to most experiments with quantum degenerate gases, optical lattices, atomic fountains and many other applications. A broad set of new applications await ultracold molecules, and the extension of laser cooling to molecules has begun. A magneto-optical trap (MOT) has been demonstrated for a single molecular species, SrF, but the sub-Doppler temperatures required for many applications have not yet been reached. Here we demonstrate a MOT of a second species, CaF, and we show how to cool these molecules to 50 μK, well below the Doppler limit, using a three-dimensional optical molasses. These ultracold molecules could be loaded into optical tweezers to trap arbitrary arrays for quantum simulation, launched into a molecular fountain for testing fundamental physics, and used to study collisions and chemistry between atoms and molecules at ultracold temperatures.

  11. Doppler flow patterns in pediatric pulmonary pathology

    International Nuclear Information System (INIS)

    Garcia, J.A.; Valdes, P.; Valls, E.; Alonso, I.; Ceres, L.

    1996-01-01

    To differentiate, in a number of pediatric lung diseases, a series of Doppler flow patterns according to their pulmonary or systemic origin, assessing the morphology of the spectral curve. We have reviewed the Doppler studies carried out in 22 patients with a variety of pulmonary pathologies, including several pulmonary abnormalities: three cases of sequestration, four cases of pulmonary vein drainage problems (one with no evidence of associated pulmonary abnormality, two with scimitar syndrome and one variant with accessory diaphragm), one case of cystic adenomatoid malformation, three cases of metastatic neoplastic lesion, one case of hydatid cyst and 10 cases of infections pathology and atelectasis, the underlying causes of which were unknown. We have found four basis patterns of pulmonary or systemic arterial and venous vascularization in ultrasonographic studies. We conclude that the use of Doppler ultrasound associated with standard ultrasonography is a very helpful tool in the initial diagnosis of pulmonary vascularization abnormalities. (Author)

  12. Rubidium Atomic Line Filtered (RALF) Doppler Velocimetry

    Science.gov (United States)

    Fajardo, Mario; Molek, Christopher; Vesely, Annamaria; Lasem Team

    2013-06-01

    We report our progress towards adapting the well-known Global Dopper Velocimetry (GDV) technique, popular in the aerodynamics community, to the order-of-magnitude higher velocities pertinent to shock experiments. In GDV, the narrow-line illumination laser is tuned to an edge of a molecular iodine absorption line; an iodine gas cell converts the Doppler shift of the reflected light to transmitted intensity. We follow the suggestion in the original 1990 patent by Komine and broaden the absorption lines of alkali metal atoms by adding a buffer gas, thereby tuning the transmission edge spectrum to match the Doppler shift (surface velocity) range of interest. We use atomic rubidium vapor cells, with 0 to 1 atmosphere pressures of molecular nitrogen buffer gas, and coin the name ``Rubidium Atomic Line Filtered'' (RALF) Doppler velocimetry. [96ABW-2013-0036

  13. Proposed protocols for peripheral and renal Doppler

    International Nuclear Information System (INIS)

    Fonseca Portuguez, Adriana

    2009-01-01

    A literature review was performed in order to prepare a summary of the important concepts of Doppler and applications in peripheral vascular evaluation and renal. The normal characteristics are summarized and explained in each vascular system and diagnostic criteria of the disorders frequently encountered in practice. Requested more studies have been identified and proposed protocols and report sheets have been developed to standardize the methodology of realization of several Doppler studies. The variability between operators has been treated to reduce as much as possible and follow-up studies have provided in patients who need. (author) [es

  14. Doppler diagnosis of deep venous thrombosis

    International Nuclear Information System (INIS)

    Nix, L.

    1984-01-01

    The venous Doppler examination has been shown to be a sensitive test for the diagnosis of deep venous thrombosis. An experienced technologist can perform the examination in about ten minutes at the bedside or in the laboratory. Because the venous Doppler examination is subjective, it requires considerable experience of the examiner to achieve maximal accuracy. Nevertheless, with sufficient practice the technologist may employ this instrument with skill and versatility to detect both obstruction and valvular incompetence in the superficial, communicating, and deep veins of the lower and upper extremities

  15. Recent Advances in Global Measurement and Application of River Widths

    Science.gov (United States)

    Pavelsky, T.; Allen, G. H.

    2015-12-01

    Among variables relevant to river form and discharge that can be observed from space, river width is perhaps the simplest to measure. Width can be extracted directly from optical or radar imagery, and application of remotely sensed widths to problems in hydrology, fluvial geomorphology, and ecology dates back more than two decades. Despite this long heritage, until very recently remotely sensed width measurements have largely been made on an ad-hoc basis for individual studies over relatively small regions. Global studies that required river widths have largely relied on estimates from downstream hydraulic geometry relationships with basin area, which inevitably simplify width variability and may, in practice, underestimate the fraction of wide rivers and the total river surface area in many basins. Over the last two years, multiple new regional- and global-scale, satellite-derived river width datasets have been developed that have substantially improved our global understanding of river form. These datasets include the Global Width Database for Large Rivers (GWD-LR), which provides width measurements for rivers wider than ~180 m, and all rivers wider than ~300 m, based on the SRTM water mask and the Global River Widths from Landsat (GRWL), which provides measurements for rivers as narrow as 30 m and all rivers wider than ~100 m. Several regional-scale datasets have also been developed. These datasets will facilitate improvements to regional and global scale hydrodynamic models, will provide more robust information on global river surface area for gas flux studies, and constitute novel information on global patterns of fluvial geomorphology. These datasets represent the beginning, not the end, of global river width measurements, however, as in the future multitemporal width measurements can be combined with recently developed algorithms to estimate river discharge for many rivers, globally.

  16. The significance of biometric parameters in determining anterior teeth width

    Directory of Open Access Journals (Sweden)

    Strajnić Ljiljana

    2013-01-01

    Full Text Available Background/Aim. An important element of prosthetic treatment of edentulous patients is selecting the size of anterior artificial teeth that will restore the natural harmony of one’s dentolabial structure as well as the whole face. The main objective of this study was to determine the correlation between the inner canthal distance (ICD and interalar width (IAW on one side and the width of both central incisors (CIW, the width of central and lateral incisors (CLIW, the width of anterior teeth (ATW, the width between the canine cusps (CCW, which may be useful in clinical practice. Methods. A total of 89 subjects comprising 23 male and 66 female were studied. Their age ranged from 19 to 34 years with the mean of 25 years. Only the subjects with the preserved natural dentition were included in the sample. All facial and intraoral tooth measurements were made with a Boley Gauge (Buffalo Dental Manufacturing Co., Brooklyn NY, USA having a resolution of 0.1mm. Results. A moderate correlation was established between the interalar width and combined width of anterior teeth and canine cusp width (r = 0.439, r = 0.374. A low correlation was established between the inner canthal distance and the width of anterior teeth and canine cusp width (r = 0.335, r = 0.303. The differences between the two genders were highly significant for all the parameters (p < 0.01. The measured facial distances and width of anterior teeth were higher in men than in women. Conclusion. The results of this study suggest that the examined interalar width and inner canthal distance cannot be considered reliable guidelines in the selection of artificial upper anterior teeth. However, they may be used as a useful additional factor combined with other methods for objective tooth selection. The final decision should be made while working on dentures fitting models with the patient’s consent.

  17. A Statistical Approach for Obtaining the Controlled Woven Fabric Width

    OpenAIRE

    Shaker Khubab; Umair Muhammad; Maqsood Muhammad; Nawab Yasir; Ahmad Sheraz; Rasheed Abher; Ashraf Munir; Basit Abdul

    2015-01-01

    A common problem faced in fabric manufacturing is the production of inconsistent fabric width on shuttleless looms in spite of the same fabric specifications. Weft-wise crimp controls the fabric width and it depends on a number of factors, including warp tension, temple type, fabric take-up pressing tension and loom working width. The aim of this study is to investigate the effect of these parameters on the fabric width produced. Taguchi’s orthogonal design was used to optimise the weaving pa...

  18. A Statistical Approach for Obtaining the Controlled Woven Fabric Width

    Directory of Open Access Journals (Sweden)

    Shaker Khubab

    2015-12-01

    Full Text Available A common problem faced in fabric manufacturing is the production of inconsistent fabric width on shuttleless looms in spite of the same fabric specifications. Weft-wise crimp controls the fabric width and it depends on a number of factors, including warp tension, temple type, fabric take-up pressing tension and loom working width. The aim of this study is to investigate the effect of these parameters on the fabric width produced. Taguchi’s orthogonal design was used to optimise the weaving parameters for obtaining controlled fabric width. On the basis of signal to noise ratios, it could be concluded that controlled fabric width could be produced using medium temple type and intense take-up pressing tension at relatively lower warp tension and smaller loom working width. The analysis of variance revealed that temple needle size was the most significant factor affecting the fabric width, followed by loom working width and warp tension, whereas take-up pressing tension was least significant of all the factors investigated in the study.

  19. Residual nilpotence and residual solubility of groups

    International Nuclear Information System (INIS)

    Mikhailov, R V

    2005-01-01

    The properties of the residual nilpotence and the residual solubility of groups are studied. The main objects under investigation are the class of residually nilpotent groups such that each central extension of these groups is also residually nilpotent and the class of residually soluble groups such that each Abelian extension of these groups is residually soluble. Various examples of groups not belonging to these classes are constructed by homological methods and methods of the theory of modules over group rings. Several applications of the theory under consideration are presented and problems concerning the residual nilpotence of one-relator groups are considered.

  20. GRIP DOPPLER AEROSOL WIND LIDAR (DAWN) V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The GRIP Doppler Aerosol WiNd Lidar (DAWN) Dataset was collected by the Doppler Aerosol WiNd (DAWN), a pulsed lidar, which operated aboard a NASA DC-8 aircraft...

  1. TCSP ER-2 DOPPLER RADAR (EDOP) V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The EDOP provides vertically profiled reflectivity and Doppler velocity at aircraft nadir along the flight track. The ER-2 Doppler radar (EDOP) is an X-band (9.6...

  2. Operational Bright-Band Snow Level Detection Using Doppler Radar

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A method to detect the bright-band snow level from radar reflectivity and Doppler vertical velocity data collection with an atmospheric profiling Doppler radar. The...

  3. ISAR imaging using the instantaneous range instantaneous Doppler method

    CSIR Research Space (South Africa)

    Wazna, TM

    2015-10-01

    Full Text Available In Inverse Synthetic Aperture Radar (ISAR) imaging, the Range Instantaneous Doppler (RID) method is used to compensate for the nonuniform rotational motion of the target that degrades the Doppler resolution of the ISAR image. The Instantaneous Range...

  4. Role of color Doppler ultrasound in the diagnosis of nonpalpable ...

    African Journals Online (AJOL)

    –0.97). Conclusion Color Doppler ultrasound is an effective noninvasive method for the initial diagnosis of impalpable testes and for planning its subsequent management. Keywords: color Doppler ultrasound, laparoscopy, nonpalpable testes ...

  5. Comparison of power Doppler and color Doppler ultrasonography in the detection of intrasticular blood flow of normal infants

    International Nuclear Information System (INIS)

    Shin, Sung Ran; Lee, Ho Kyoung; Lee, Won Gyun; Youk, Dong Joon; Rho, Taek Soo; Lee, Min Jin; Lee, Sang Chun

    1999-01-01

    To compare color Doppler ultrasonography (US) and power Doppler US in the detection of intratesticular blood flow in normal infants and to asses the symmetry of blood flow. Testicular blood flow was assessed prospectively in 100 testes of 50 infants with both power and color Doppler US. We compared the power Doppler with color Doppler to detect intratesticular blood. When the flow was detected, intratesticular blood flow was graded as follows: grade 1: single intratesticular Doppler signal ; grade 2: multiple intratesticular Doppler signals. The symmetry of intratesticular flow was assessed by using the same method. Intratesticular flow was detected in 72 (72%) and 68 (68%) testes on power and color Doppler US, respectively. In 76 testes (76%), intratesticular flow was detected in either one or both techniques. On power Doppler US, grade 1 was seen in 40 tests and grade 2 in 32 testes. On color Doppler US, grade 1 was noted in 52 testes and grade 2 in 16 testes. Testicular blood flow was symmetric on both power and color Doppler US in each patient. There was no difference between power Doppler and color Doppler ultrasonography in detecting intratesticular blood flow in normal infants.

  6. Determination of normal maxillary transverse dimension by using intercanine width and interpalatal first molar width.

    Science.gov (United States)

    Banker, Alka M; Pillai, Jayasankar P; Patel, Kinjal D

    2016-01-01

    Malocclusion in the vertical and sagittal planes is easy to observe whereas it is difficult to diagnose malocclusion in the transverse plane. There are yet no criteria defining a normal transverse occlusion. The aim of this study was to identify a ratio that defines a normal transverse occlusion. This was a retrospective study. A total sample of 151 maxillary dental models (M = 55, F = 96) in the age range of 12-16 years were randomly selected, with 73 models in control group and 78 in the study group. All the models were mixed up and given to an operator for the measurement of intercanine width (ICW) and inter-palatal molar width (IPMW). The data were statistically analyzed using SPSS software version 16.0. Chi-square test was performed to test the statistical significance difference between the groups at p ≤ 0.05. Nearly 98.60% of normal arches were found to have an IPMW to ICW ratio of 1:1 ± 0.05. On further analysis, it was found that when IPMW ≥37.45 mm, then the case may be considered to have normal arches, and if the ratio between IPMW to ICW is 1.15:1 ± 0.05 or more and IPMW is dimension.

  7. Linear and nonlinear light propagations in a Doppler-broadened medium via electromagnetically induced transparency

    International Nuclear Information System (INIS)

    Li Liang; Huang Guoxiang

    2010-01-01

    We present a systematic theoretical study to deal with linear and nonlinear light propagations in a Doppler-broadened three-level Λ system via electromagnetically induced transparency (EIT), with incoherent population exchange between two lower energy levels taken into account. Through a careful analysis of base state and linear excitation, we show that the EIT condition of the system is given by |Ω c | 2 γ 31 >>2γ 21 Δω D 2 , where Ω c is half the Rabi frequency of the control field, Δω D is the Doppler width, and γ jl is the decay rate of the coherence between states |j> and |l>. Under this condition, the effect of incoherent population exchange is insignificant, while dephasing dominates the decoherence of the system. This condition also ensures the validity of the weak nonlinear perturbation theory used in this work for solving the Maxwell-Bloch equations with inhomogeneous broadening. We then investigate the nonlinear propagation of the probe field and show that it is possible to form temporal optical solitons in the Doppler-broadened medium. Such solitons have ultraslow propagating velocity and can be generated in very low light power. The possibility of realizing (1+1)-dimensional and (2+1)-dimensional spatial optical solitons in the adiabatic regime of the system is also discussed.

  8. Doppler Processing with Ultra-Wideband (UWB) Radar Revisited

    Science.gov (United States)

    2018-01-01

    Doppler processing in radar systems using ultra-wideband (UWB) waveforms. In light of more recent research in this area, we demonstrate that exact...Doppler frequency B – pulse bandwidth v – radial velocity of the target c – speed of light ρ – variable representing the Fourier pair of range (R...Typically, Doppler processing in radar consists of creating range-Doppler (R/D) maps—these are 2-D reflectivity maps of the scene under investigation by the

  9. Spectral Doppler of the hepatic veins in tricuspid valve disease.

    Science.gov (United States)

    Fadel, Bahaa M; Almulla, Khaled; Husain, Aysha; Dahdouh, Ziad; Di Salvo, Giovanni; Mohty, Dania

    2015-05-01

    Spectral Doppler recording of the hepatic veins (HV) provides a semiquantitative assessment of tricuspid regurgitation (TR) severity. It complements findings on two-dimensional echocardiography and color Doppler imaging and helps to discriminate between hemodynamically significant and nonsignificant degree of regurgitation. In this manuscript, we discuss the usefulness of the HV Doppler for the diagnosis of tricuspid valve (TV) disease and provide examples of the various spectral Doppler patterns that assist in the quantification of TR. © 2014, Wiley Periodicals, Inc.

  10. Doppler Shift Compensation Schemes in VANETs

    Directory of Open Access Journals (Sweden)

    F. Nyongesa

    2015-01-01

    Full Text Available Over the last decade vehicle-to-vehicle (V2V communication has received a lot of attention as it is a crucial issue in intravehicle communication as well as in Intelligent Transportation System (ITS. In ITS the focus is placed on integration of communication between mobile and fixed infrastructure to execute road safety as well as nonsafety information dissemination. The safety application such as emergence alerts lays emphasis on low-latency packet delivery rate (PDR, whereas multimedia and infotainment call for high data rates at low bit error rate (BER. The nonsafety information includes multimedia streaming for traffic information and infotainment applications such as playing audio content, utilizing navigation for driving, and accessing Internet. A lot of vehicular ad hoc network (VANET research has focused on specific areas including channel multiplexing, antenna diversity, and Doppler shift compensation schemes in an attempt to optimize BER performance. Despite this effort few surveys have been conducted to highlight the state-of-the-art collection on Doppler shift compensation schemes. Driven by this cause we survey some of the recent research activities in Doppler shift compensation schemes and highlight challenges and solutions as a stock-taking exercise. Moreover, we present open issues to be further investigated in order to address the challenges of Doppler shift in VANETs.

  11. Quantum Theory of the Doppler Effect

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 1; Issue 10. Quantum Theory of the Doppler Effect. G S Ranganath. Classroom Volume 1 Issue 10 October 1996 pp 76-78. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/001/10/0076-0078 ...

  12. Doppler Sonographic Evaluation of Venogenic Extremity Swellings ...

    African Journals Online (AJOL)

    2017-09-14

    Sep 14, 2017 ... potentially lead to many complications including life-threatening pulmonary arterial thrombosis. Screening and confirmation ... and exclusion of acute lower extremity DVT. Duplex ultrasound is considered as the ... this study evaluates the role of Doppler sonography in the clinical management of suspected.

  13. Transcranial Doppler velocimetry in aneurysmal subarachnoid haemorrhage

    DEFF Research Database (Denmark)

    Staalsø, J M; Edsen, T; Romner, B

    2013-01-01

    -coded transcranial Doppler (TCCD), with the secondary aim of describing prediction of angiographic vasospasm and mortality. METHODS: /st>Sixty patients and 70 healthy controls were each examined in duplicate by alternating operators. A total of 939 measurements divided on 201 examination sets were conducted by four...

  14. Doppler sonographic evaluation of venogenic extremity swellings ...

    African Journals Online (AJOL)

    Doppler ultrasound is very useful in the evaluation of extremity DVT. All clinically suspected cases should be evaluated with this modality due to limited sensitivity of clinical evaluation in the diagnosis of DVT. Further correlative studies in comparison to venography and hematologic indices are also recommended.

  15. An endoscopic Doppler probe: preliminary clinical evaluation

    NARCIS (Netherlands)

    Silverstein, F. E.; Deltenre, M.; Tytgat, G.; Martin, R. W.; Lesterhuis, W.; Burette, A.; Gilbert, D. A.

    1985-01-01

    A new pulsed Doppler catheter has been developed for use during gastrointestinal fiberendoscopy. Modern gastrointestinal endoscopy allows inspection of the wall of the entire esophagus, stomach, duodenum, and colon. Diagnosis is performed by inspecting the surface of the mucosa, biopsy, and

  16. Ultrasonic Doppler color in glaucoma: Concordance study

    International Nuclear Information System (INIS)

    Uriza, Felipe; Useche, Nicolas

    2005-01-01

    Our study demonstrates that US color Doppler is a non invasive, reliable and reproducible method for the evaluation of the orbitary flow in normal and glaucomatous patients. However is suggested that every group evaluates the inter and intraobserver variability because of the lack of universal reference velocity measurements

  17. Coherent Detection in Laser Doppler Velocimeters

    DEFF Research Database (Denmark)

    Hanson, Steen Grüner

    1974-01-01

    , but intelligible particle picture of electromagnetic waves. The analysis is carried out with special emphasis on the heterodyning process in the laser Doppler velocimeter (LDV) because the main purpose of this article is to provide a better understanding of this instrument. An aid for this purpose...

  18. Radar micro-doppler signatures processing and applications

    CERN Document Server

    Chen, Victor C; Miceli, William J

    2014-01-01

    Radar Micro-Doppler Signatures: Processing and applications concentrates on the processing and application of radar micro-Doppler signatures in real world situations, providing readers with a good working knowledge on a variety of applications of radar micro-Doppler signatures.

  19. Use of the implantable Doppler in free tissue breast reconstruction.

    Science.gov (United States)

    Bedri, Mazen I; Chang, Bernard W

    2011-04-01

    In this article, the authors discuss the advances in monitoring free tissue transfers, with a focus on the implantable Doppler system. Authors address indications and techniques for implanting the Doppler system, in addition to presenting a framework to assess the reliability and potential benefits of the implantable Doppler device. Copyright © 2011 Elsevier Inc. All rights reserved.

  20. TCSP ER-2 DOPPLER RADAR (EDOP) V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The TCSP ER-2 DOPPLER RADAR (EDOP) dataset was collected by the ER-2 Doppler radar (EDOP), which is an X-band (9.6 GHz) Doppler radar mounted in the nose of the ER-2...

  1. CAMEX-4 ER-2 DOPPLER RADAR V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The CAMEX-4 ER-2 Doppler Radar dataset was collected by the ER-2 Doppler radar (EDOP), which is an X-band (9.6 GHz) Doppler radar mounted in the nose of ER-2. The...

  2. On acceleration dependence of Doppler effect in light

    Indian Academy of Sciences (India)

    Using only the geometric relationships of suitable locations, we analyse Doppler effect in light to show how the acceleration of the source also contributes to the Doppler shift. We further propose that an experiment be performed using cyclotron-type devices to determine the acceleration dependence of the Doppler shift.

  3. Stream water responses to timber harvest: Riparian buffer width effectiveness

    Science.gov (United States)

    Barton D. Clinton

    2011-01-01

    Vegetated riparian buffers are critical for protecting aquatic and terrestrial processes and habitats in southern Appalachian ecosystems. In this case study, we examined the effect of riparian buffer width on stream water quality following upland forest management activities in four headwater catchments. Three riparian buffer widths were delineated prior to cutting; 0m...

  4. Evolution of giant dipole resonance width at low temperatures ...

    Indian Academy of Sciences (India)

    The resonance width. GDR is defined as the full-width at half-maximum (FWHM) of the GDR lineshape and is related to various damping mechanisms of the collective motion inside nuclear matter. The damping of giant collective vibration inside the nuclear medium occurs either due to escape of resonance energy by means ...

  5. A STATISTICAL APPROACH FOR OBTAINING THE CONTROLLED WOVEN FABRIC WIDTH

    NARCIS (Netherlands)

    Maqsood, Muhammad

    2015-01-01

    A common problem faced in fabric manufacturing is the production of inconsistent fabric width on shuttleless looms in spite of the same fabric specifications. Weft-wise crimp controls the fabric width and it depends on a number of factors, including warp tension, temple type, fabric take-up pressing

  6. Enhancement of heat transfer using varying width twisted tape inserts

    African Journals Online (AJOL)

    Enhancement of heat transfer using varying width twisted tape inserts. ... International Journal of Engineering, Science and Technology ... The present work shows the results obtained from experimental investigations of the augmentation of turbulent flow heat transfer in a horizontal tube by means of varying width twisted ...

  7. Doppler speedometer for micro-organisms

    International Nuclear Information System (INIS)

    Penkov, F.; Tuleushev, A.; Lisitsyn, V.; Kim, S.; Tuleushev, Yu.

    1996-01-01

    Objective of Investigations: Development and creation of the Doppler speedometer for micro-organisms which allows to evaluate, in a real temporal scale, variations in the state of water suspension of micro-organisms under the effect of chemical, physical and other external actions. Statement of the Problem The main problem is absence of reliable, accessible for users and simple, in view of application, Doppler speedometers for micro-organisms. Nevertheless, correlation Doppler spectrometry in the regime of heterodyning the supporting and cell-scattered laser radiation is welt known. The main idea is that the correlation function of photo-current pulses bears an information on the averages over the assembly of cell velocities. For solving the biological problems, construction of auto-correlation function in the real-time regime with the delay time values comprising, function in the real-time regime with the delay time values comprising, nearly, 100 me (10 khz) or higher is needed. Computers of high class manage this problem using but the program software. Due to this, one can simplify applications of the proposed techniques provided he creates the Doppler speedometer for micro-organism on a base of the P entium . Expected Result Manufactured operable mock-up of the Doppler speedometer for micro-organisms in a form of the auxiliary computer block which allows to receive an information, in the real time scale, on the results of external effects of various nature on the cell assembly in transparent medium with a small volume of the studied cell suspension

  8. Acute hemodialysis effects on doppler echocardiographic indices

    Directory of Open Access Journals (Sweden)

    Leila Abid

    2014-01-01

    Full Text Available Conventional echocardiographic (ECHO parameters of systolic and diastolic func-tion of the left ventricular (LV have been shown to be load dependent. However, the impact of pre-load reduction on tissue Doppler (TD parameters of LV function is incompletely understood. To evaluate the effect of a single hemodialysis (HD session on LV systolic and diastolic function using pulsed Doppler echocardiography and pulsed tissue Doppler imaging (TDI, we studied 81chronic HD patients (40 males; mean age 52.4 ± 16.4 years with these tools. ECHO parameters were obtained 30 min before and 30 min after HD. Fluid volume removed by HD was 1640 ± 730 cm [3] . HD led to reduction in LV end-diastolic volume (P <0.001, end-systolic volume (P <0.001, left atrium area (P <0.001, peak early (E-wave trans-mitral flow velocity (P <0.001, the ratio of early to late Doppler velocities of diastolic mitral inflow (P <0.001 and aortic time velocity integral (P <0.001. No significant change in peak S velocity of pulmonary vein flow after HD was noted. Early and late diastolic (E′ TDI velocities and the ratio of early to late TDI diastolic velocities (E′/A′ on the lateral side of the mitral annulus decreased signi-ficantly after HD (P = 0.013; P = 0.007 and P = 0.008, respectively. Velocity of flow progres-sion (Vp during diastole was not affected by pre-load reduction. Pulmonary artery systolic pressure and the diameter of the inferior vena cava decreased significantly (P <0.001 and P <0.001, respectively after HD. We conclude that most of the Doppler-derived indices of diastolic function are pre-load-dependent and velocity of flow progression was minimally affected by pre-load reduction in HD patients.

  9. Difference of CBD width on US vs. ERCP.

    Science.gov (United States)

    Brook, Olga R; Suissa, Alain; Khamaysi, Iyad; Koren, Dorit; Gaitini, Diana

    2007-01-01

    To investigate the relationship between US and ERCP in the measurement of common bile duct (CBD) width after application of Compound and Harmonic imaging on ultrasound. We prospectively evaluated the CBD width as measured on endoscopic retrograde cholangiopancreatography (ERCP) and ultrasonography (US), applying Compound and Harmonic US techniques, on 100 patients. Furthermore, we retrospectively re-examined US and ERCP images of 48 patients who underwent ERCP and US during the same hospitalization period. The average difference in measurements by US compared to ERCP was 2.3 mm (P CBD width. There was a good correlation between ERCP and US measurements of CBD width (r = 0.73 for all patients and r = 0.88 for patients with intact gallbladder, P CBD width on US and ERCP of about 2 mm. The application of Compound and Harmonic techniques in the prospective study probably enabled a more accurate sonographic measurement.

  10. Effect of step width manipulation on tibial stress during running.

    Science.gov (United States)

    Meardon, Stacey A; Derrick, Timothy R

    2014-08-22

    Narrow step width has been linked to variables associated with tibial stress fracture. The purpose of this study was to evaluate the effect of step width on bone stresses using a standardized model of the tibia. 15 runners ran at their preferred 5k running velocity in three running conditions, preferred step width (PSW) and PSW±5% of leg length. 10 successful trials of force and 3-D motion data were collected. A combination of inverse dynamics, musculoskeletal modeling and beam theory was used to estimate stresses applied to the tibia using subject-specific anthropometrics and motion data. The tibia was modeled as a hollow ellipse. Multivariate analysis revealed that tibial stresses at the distal 1/3 of the tibia differed with step width manipulation (p=0.002). Compression on the posterior and medial aspect of the tibia was inversely related to step width such that as step width increased, compression on the surface of tibia decreased (linear trend p=0.036 and 0.003). Similarly, tension on the anterior surface of the tibia decreased as step width increased (linear trend p=0.029). Widening step width linearly reduced shear stress at all 4 sites (p<0.001 for all). The data from this study suggests that stresses experienced by the tibia during running were influenced by step width when using a standardized model of the tibia. Wider step widths were generally associated with reduced loading of the tibia and may benefit runners at risk of or experiencing stress injury at the tibia, especially if they present with a crossover running style. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. Line width and line shape analysis in the inductively coupled plasma by high resolution Fourier transform spectrometry

    International Nuclear Information System (INIS)

    Faires, L.M.; Palmer, B.A.; Brault, J.W.

    1984-01-01

    High resolution Fourier transform spectrometry has been used to perform line width and line shape analysis of eighty-one iron I emision lines in the spectral range 290 to 390nm originating in the normal analytical zone of an inductively coupled plasma. Computer programs using non-linear least squares fitting techniques for line shape analysis were applied to the fully resolved spectra to determine Gaussian and Lorentzian components of the total observed line width. The effect of noise in the spectrum on the precision of the line fitting technique was assessed, and the importance of signal to noise ratio for line shape analysis is discussed. Translational (Doppler) temperatures were calculated from the Gaussian components of the line width and were found to be on the order of 6300 0 K. The excitation temperature of iron I was also determined from the same spectral data by the spectroscopic slope method based on the Einstein-Boltzmann expression for spectral intensity and was found to be on the order of 4700 0 K. 31 references

  12. Flow Pattern in Ventilated Rooms with Large Depth and Width

    DEFF Research Database (Denmark)

    Yue, Zou; Nielsen, Peter V.

    In this paper both model experiments and Computational Fluid Dynamics (CFD) are employed to study the isothennal flow pattern in the ventilated room with different UH and inlet velocities. The maximum size of the model is 1.4* 0.72*0.0714m and the measurement is made by a Laser Doppler anemometer....

  13. Nightside studies of coherent HF Radar spectral width behaviour

    Directory of Open Access Journals (Sweden)

    E. E. Woodfield

    2002-09-01

    Full Text Available A previous case study found a relationship between high spectral width measured by the CUTLASS Finland HF radar and elevated electron temperatures observed by the EISCAT and ESR incoherent scatter radars in the post-midnight sector of magnetic local time. This paper expands that work by briefly re-examining that interval and looking in depth at two further case studies. In all three cases a region of high HF spectral width (>200 ms-1 exists poleward of a region of low HF spectral width (<200 ms-1. Each case, however, occurs under quite different geomagnetic conditions. The original case study occurred during an interval with no observed electrojet activity, the second study during a transition from quiet to active conditions with a clear band of ion frictional heating indicating the location of the flow reversal boundary, and the third during an isolated sub-storm. These case studies indicate that the relationship between elevated electron temperature and high HF radar spectral width appears on closed field lines after 03:00 magnetic local time (MLT on the nightside. It is not clear whether the same relationship would hold on open field lines, since our analysis of this relationship is restricted in latitude. We find two important properties of high spectral width data on the nightside. Firstly the high spectral width values occur on both open and closed field lines, and secondly that the power spectra which exhibit high widths are both single-peak and multiple-peak. In general the regions of high spectral width (>200 ms-1 have more multiple-peak spectra than the regions of low spectral widths whilst still maintaining a majority of single-peak spectra. We also find that the region of ion frictional heating is collocated with many multiple-peak HF spectra. Several mechanisms for the generation of high spectral width have been proposed which would produce multiple-peak spectra, these are discussed in relation to the data presented here. Since the

  14. Influence of pulse width and detuning on coherent phonon generation

    Science.gov (United States)

    Nakamura, Kazutaka G.; Shikano, Yutaka; Kayanuma, Yosuke

    2015-10-01

    We investigated the coherent phonon generation mechanism by irradiation of an ultrashort pulse with a simple two-level model. Our derived formulation shows that both impulsive stimulated Raman scattering (ISRS) and impulsive absorption (IA) simultaneously occur, and phonon wave packets are generated in the electronic ground and excited states by ISRS and IA, respectively. We identify the dominant process from the amplitude of the phonon oscillation. For short pulse widths, ISRS is very small and becomes larger as the pulse width increases. We also show that the initial phase is dependent on the pulse width and the detuning.

  15. Nightside studies of coherent HF Radar spectral width behaviour

    Directory of Open Access Journals (Sweden)

    E. E. Woodfield

    Full Text Available A previous case study found a relationship between high spectral width measured by the CUTLASS Finland HF radar and elevated electron temperatures observed by the EISCAT and ESR incoherent scatter radars in the post-midnight sector of magnetic local time. This paper expands that work by briefly re-examining that interval and looking in depth at two further case studies. In all three cases a region of high HF spectral width (>200 ms-1 exists poleward of a region of low HF spectral width (<200 ms-1. Each case, however, occurs under quite different geomagnetic conditions. The original case study occurred during an interval with no observed electrojet activity, the second study during a transition from quiet to active conditions with a clear band of ion frictional heating indicating the location of the flow reversal boundary, and the third during an isolated sub-storm. These case studies indicate that the relationship between elevated electron temperature and high HF radar spectral width appears on closed field lines after 03:00 magnetic local time (MLT on the nightside. It is not clear whether the same relationship would hold on open field lines, since our analysis of this relationship is restricted in latitude. We find two important properties of high spectral width data on the nightside. Firstly the high spectral width values occur on both open and closed field lines, and secondly that the power spectra which exhibit high widths are both single-peak and multiple-peak. In general the regions of high spectral width (>200 ms-1 have more multiple-peak spectra than the regions of low spectral widths whilst still maintaining a majority of single-peak spectra. We also find that the region of ion frictional heating is collocated with many multiple-peak HF spectra. Several mechanisms for the generation of high spectral width have been proposed which would produce multiple-peak spectra, these are discussed in relation to

  16. Finite-width plasmonic waveguides with hyperbolic multilayer cladding.

    Science.gov (United States)

    Babicheva, Viktoriia E; Shalaginov, Mikhail Y; Ishii, Satoshi; Boltasseva, Alexandra; Kildishev, Alexander V

    2015-04-20

    Engineering plasmonic metamaterials with anisotropic optical dispersion enables us to tailor the properties of metamaterial-based waveguides. We investigate plasmonic waveguides with dielectric cores and multilayer metal-dielectric claddings with hyperbolic dispersion. Without using any homogenization, we calculate the resonant eigenmodes of the finite-width cladding layers, and find agreement with the resonant features in the dispersion of the cladded waveguides. We show that at the resonant widths, the propagating modes of the waveguides are coupled to the cladding eigenmodes and hence, are strongly absorbed. By avoiding the resonant widths in the design of the actual waveguides, the strong absorption can be eliminated.

  17. Transcranial Doppler sonography in familial hemiplegic migraine

    International Nuclear Information System (INIS)

    Pierelli, F.; Pauri, F.; Cupini, L.M.; Fiermonte, G.; Rizzo, P.A.

    1991-01-01

    A patient affected by familial hemiplegic migraine underwent transcranial Doppler sonography twice: the first during a spontaneous attack with right hemiparesis and aphasia, the second during a headachefree period. During the attack the following haemodynamic changes were seen: (a) bilateral increase in the middle cerebral artery and anterior cerebral artery blood flow velocities (this increase was more pronounced on the left side), (b) decreased systo-diastolic ratio and pulsatility index on the right side, (c) increased systo-diastolic ratio and pulsatility index on the left side. The results indicate that during the attack in this familial hemiplegic migraine patient, a diffuse vasoconstriction of the basal cerebral arteries developed. Moreover, transcranial Doppler sonography data suggest that a prolonged vasoconstriction of the peripheral arterioles could play a role in determining the neurological symptoms in this syndrome. 13 refs., 1 figs., 1 tab

  18. Transcranial Doppler sonography in familial hemiplegic migraine

    Energy Technology Data Exchange (ETDEWEB)

    Pierelli, F.; Pauri, F.; Cupini, L.M.; Fiermonte, G.; Rizzo, P.A. (Universita la Sapienza, Roma (Italy))

    1991-02-01

    A patient affected by familial hemiplegic migraine underwent transcranial Doppler sonography twice: the first during a spontaneous attack with right hemiparesis and aphasia, the second during a headachefree period. During the attack the following haemodynamic changes were seen: (a) bilateral increase in the middle cerebral artery and anterior cerebral artery blood flow velocities (this increase was more pronounced on the left side), (b) decreased systo-diastolic ratio and pulsatility index on the right side, (c) increased systo-diastolic ratio and pulsatility index on the left side. The results indicate that during the attack in this familial hemiplegic migraine patient, a diffuse vasoconstriction of the basal cerebral arteries developed. Moreover, transcranial Doppler sonography data suggest that a prolonged vasoconstriction of the peripheral arterioles could play a role in determining the neurological symptoms in this syndrome. 13 refs., 1 figs., 1 tab.

  19. MEMS based Doppler velocity measurement system

    Science.gov (United States)

    Shin, Minchul

    The design, fabrication, modeling and characterization of a capacitive micromachined ultrasonic transducer (cMUT) based in-air Doppler velocity measurement system using a 1 cm2 planar array are described. Continuous wave operation in a narrowband was chosen in order to maximize range, as it allows for better rejection of broadband noise. The sensor array has a 160-185 kHz resonant frequency to achieve a 10 degree beamwidth. A model for the cMUT and the acoustic system which includes electrical, mechanical, and acoustic components is provided. Furthermore, characterization of the cMUT sensor with a variety of testing procedures is provided. Laser Doppler vibrometry (LDV), beampattern, reflection, and velocity testing characterize the performance of the sensors. The sensor is capable of measuring the velocity of a moving specular reflector with a resolution of 5 cm/s, an update rate of 0.016 second, and a range of 1.5 m.

  20. Color Doppler US of the penis

    International Nuclear Information System (INIS)

    Bertolotto, Michele

    2008-01-01

    This book provides a comprehensive reference and practical guide on the application of US to penile diseases and conditions. After introductory chapters on technical requirements and penile anatomy, subsequent chapters offer a systematic overview of the diverse applications of color Doppler US. The topics covered include erectile dysfunction, Peyronie's disease, priapism, trauma, tumors, the postoperative penis, inflammation, and fibrosis. Each topic is introduced by a clinical overview with the purpose of clarifying the problems and elucidating what the urologist may expect from color Doppler US. Thereafter, performance of the US study is explained and the pathological anatomy reviewed. High-quality images obtained with high-end US equipment are included. Each chapter also contains a section on the diagnostic information provided by other imaging modalities, and in particular MRI. (orig.)

  1. Color Doppler US of the penis

    Energy Technology Data Exchange (ETDEWEB)

    Bertolotto, Michele (ed.) [Trieste Univ. Ospedale di Cattinara (Italy). Dept. Radiology

    2008-07-01

    This book provides a comprehensive reference and practical guide on the application of US to penile diseases and conditions. After introductory chapters on technical requirements and penile anatomy, subsequent chapters offer a systematic overview of the diverse applications of color Doppler US. The topics covered include erectile dysfunction, Peyronie's disease, priapism, trauma, tumors, the postoperative penis, inflammation, and fibrosis. Each topic is introduced by a clinical overview with the purpose of clarifying the problems and elucidating what the urologist may expect from color Doppler US. Thereafter, performance of the US study is explained and the pathological anatomy reviewed. High-quality images obtained with high-end US equipment are included. Each chapter also contains a section on the diagnostic information provided by other imaging modalities, and in particular MRI. (orig.)

  2. Predictive value of tissue Doppler imaging for left ventricular ejection fraction, remodelling, and infarct size after percutaneous coronary intervention for acute myocardial infarction

    NARCIS (Netherlands)

    van Melle, Joost P.; van der Vleuten, Pieter A.; Hummel, Yoran M.; Nijveldt, Robin; Tio, Rene A.; Voors, Adriaan A.; Zijlstra, Felix

    To investigate in ST-elevation myocardial infarction (STEMI) patients the value of tissue Doppler imaging (TDI) for an early estimation of the extent of myocardial salvage, left ventricular (LV) remodelling, and residual LV ejection fraction (LVEF). In 50 STEMI patients hospitalized for primary

  3. Colour Doppler ultrasound of the penis

    Energy Technology Data Exchange (ETDEWEB)

    Wilkins, C.J.; Sriprasad, S.; Sidhu, P.S. E-mail: paulsidhu@compuserve.com

    2003-07-01

    Because it is a superficial structure, the penis is ideally suited to ultrasound imaging. A number of disease processes, including Peyronie's disease, penile fractures and penile tumours, are clearly visualized with ultrasound. An assessment of priapism can also be made using spectral Doppler waveform technology. Furthermore, dynamic assessment of cavernosal arterial changes after pharmaco-stimulation allows diagnosis of arterial and venogenic causes for impotence. This pictorial review illustrates the range of diseases encountered with ultrasound of the penis.

  4. Colour Doppler ultrasound of the penis

    International Nuclear Information System (INIS)

    Wilkins, C.J.; Sriprasad, S.; Sidhu, P.S.

    2003-01-01

    Because it is a superficial structure, the penis is ideally suited to ultrasound imaging. A number of disease processes, including Peyronie's disease, penile fractures and penile tumours, are clearly visualized with ultrasound. An assessment of priapism can also be made using spectral Doppler waveform technology. Furthermore, dynamic assessment of cavernosal arterial changes after pharmaco-stimulation allows diagnosis of arterial and venogenic causes for impotence. This pictorial review illustrates the range of diseases encountered with ultrasound of the penis

  5. De-Dopplerization of Acoustic Measurements

    Science.gov (United States)

    2017-08-10

    spectrum at a chosen resolution through application of digital filter bank . This spectrum is defined at a measurement time, or time of arrival for...calculated with a one-third-octave band filter bank employing Butterworth digital filters. To examine the results of the FOBS correction, Fig. 4...band energy obtained from fractional octave band digital filters generates a de-Dopplerized spectrum without complex resampling algorithms. An

  6. Doppler Lidar Wind Value-Added Product

    Energy Technology Data Exchange (ETDEWEB)

    Newsom, R. K. [DOE ARM Climate Research Facility, Washington, DC (United States); Sivaraman, C. [DOE ARM Climate Research Facility, Washington, DC (United States); Shippert, T. R. [DOE ARM Climate Research Facility, Washington, DC (United States); Riihimaki, L. D. [DOE ARM Climate Research Facility, Washington, DC (United States)

    2015-07-01

    Wind speed and direction, together with pressure, temperature, and relative humidity, are the most fundamental atmospheric state parameters. Accurate measurement of these parameters is crucial for numerical weather prediction. Vertically resolved wind measurements in the atmospheric boundary layer are particularly important for modeling pollutant and aerosol transport. Raw data from a scanning coherent Doppler lidar system can be processed to generate accurate height-resolved measurements of wind speed and direction in the atmospheric boundary layer.

  7. Revisiting the four-level inverted-Y system under both Doppler-free and Doppler-broadened conditions: an analytical approach

    International Nuclear Information System (INIS)

    Ghosh, Arindam; Islam, Khairul; Bandyopadhyay, Amitava; Bhattacharyya, Dipankar

    2016-01-01

    We report the occurrence of electromagnetically induced transparency (EIT) in the simulated probe response signal for a four-level inverted-Y type system that is being acted upon by a weak coherent probe field, a strong coherent pump field and a coherent repump field. There are two ground energy levels, one intermediate energy level and one uppermost energy level. The weak probe field couples the lowest ground level to the intermediate level whereas the repump field connects the other ground level with the intermediate level. The strong control field couples the intermediate level with the uppermost energy level, thereby forming an inverted-Y type system. The density matrix based theoretical model has been developed and solved analytically for this four-level system and the probe response signal has been simulated at different values of the control and repump Rabi frequencies, control and repump frequency detunings and under both Doppler-free and Doppler-broadened conditions using the parameters of 87 Rb D 2 transition. Extremely low line width (few tens of kHz) for the EIT signal has been noticed under thermal averaging for copropagating probe, control and repump field configuration. The EIT signal is found to be immune to the variation in the control Rabi frequency. (paper)

  8. Doppler sonographic findings in testicular microlithiasis

    Directory of Open Access Journals (Sweden)

    Selim Serter

    2008-08-01

    Full Text Available OBJECTIVE: The aim of this prospective study was to compare the resistive index (RI values, which is a parameter of testicular parenchymal perfusion, in testicular microlithiasis (TM cases and normal cases. MATERIALS AND METHODS: 2179 volunteers, all healthy men (17-42 years of age from the Annual Army Reserve Officer Training Corps training camp were included in the study. A screening scrotal ultrasound was performed and all men diagnosed with TM underwent a scrotal Doppler ultrasonography scan (US. US examinations were performed for subjects with TM and without TM as a control group and RI was determined. RESULTS: 53 men with TM were identified in the 2179 US. Spectral Doppler examination was applied to 50 randomly selected cases (100 testicles without TM and 92 testicles with TM, 39 cases (78 testicles with bilateral and 14 cases with unilateral involvement. However, 48 normal testicles (17 bilateral and 14 unilateral and 47 testicles with TM (15 bilateral and 17 unilateral, 10 of which were cases with bilateral TM where flow from the centripetal artery could be obtained and analyzed were included in the statistical analysis for resistive indices. There was no significant difference regarding the RI and spectral examinations between subjects with and without TM. An interesting finding was the twinkling artifact observed in three cases. CONCLUSION: Microliths did not alter the RI values and thus had no influence on testicular perfusion on Doppler US examination.

  9. Doppler Lidar for Wind Measurements on Venus

    Science.gov (United States)

    Singh, Upendra N.; Emmitt, George D.; Yu, Jirong; Kavaya, Michael J.

    2010-01-01

    NASA Langley Research Center has a long history of developing 2-micron laser transmitter for wind sensing. With support from NASA Laser Risk Reduction Program (LRRP) and Instrument Incubator Program (IIP), NASA Langley Research Center has developed a state-of-the-art compact lidar transceiver for a pulsed coherent Doppler lidar system for wind measurement. The transmitter portion of the transceiver employs the high-pulse-energy, Ho:Tm:LuLiF, partially conductively cooled laser technology developed at NASA Langley. The transceiver is capable of 250 mJ pulses at 10 Hz. It is very similar to the technology envisioned for coherent Doppler lidar wind measurements from Earth and Mars orbit. The transceiver is coupled to the large optics and data acquisition system in the NASA Langley VALIDAR mobile trailer. The large optics consists of a 15-cm off-axis beam expanding telescope, and a full-hemispheric scanner. Vertical and horizontal vector winds are measured, as well as relative backscatter. The data acquisition system employs frequency domain velocity estimation and pulse accumulation. It permits real-time display of the processed winds and archival of all data. This lidar system was recently deployed at Howard University facility in Beltsville, Mary-land, along with other wind lidar systems. Coherent Doppler wind lidar ground-based wind measurements and comparisons with other sensors will be presented. A simulation and data product for wind measurement at Venus will be presented.

  10. Relationship between width of greater trochanters and width of iliac wings in tronchanteric bursitis.

    Science.gov (United States)

    Viradia, Neal K; Berger, Alex A; Dahners, Laurence E

    2011-09-01

    Trochanteric bursitis is a common disorder that is characterized by inflammation of the bursa, superficial to the greater trochanter of the femur, leading to pain in the lateral hip, and often occurs because of acute trauma or repetitive friction involving the iliotibial band, the greater trochanter, and the bursa. In the study reported here, we hypothesized that the increased incidence of bursitis may be the result of the increased prominence of the trochanter in relation to the wings of the iliac crest. Distances between the outermost edges of trochanters and iliac wings were measured in 202 patients from the University of North Carolina Health Care System-101 without a known diagnosis and 101 with a clinical diagnosis of trochanteric bursitis. To determine significance, t tests for nonpaired data were used. Mean (SD) difference between trochanter and iliac wing widths was 28 (20) mm in the group diagnosed with trochanteric bursitis and 17 (18) mm in the control group. The difference between the groups in this regard was significant (Pbursitis group and 1.05 (.06) in the control group. The difference between these groups was significant (Pbursitis.

  11. Line Width Recovery after Vectorization of Engineering Drawings

    Directory of Open Access Journals (Sweden)

    Gramblička Matúš

    2016-12-01

    Full Text Available Vectorization is the conversion process of a raster image representation into a vector representation. The contemporary commercial vectorization software applications do not provide sufficiently high quality outputs for such images as do mechanical engineering drawings. Line width preservation is one of the problems. There are applications which need to know the line width after vectorization because this line attribute carries the important semantic information for the next 3D model generation. This article describes the algorithm that is able to recover line width of individual lines in the vectorized engineering drawings. Two approaches are proposed, one examines the line width at three points, whereas the second uses a variable number of points depending on the line length. The algorithm is tested on real mechanical engineering drawings.

  12. The effect of buffer zone width on biodiversity

    DEFF Research Database (Denmark)

    Navntoft, Søren; Sigsgaard, Lene; Kristensen, Kristian

    2012-01-01

    attention in previous studies. In this paper we report on finding for syrphids, spiders and carabids, three taxonomic groups with different mobility, all important for conservation biological control. For all groups we found an effect of buffer zone width on their density. A buffer width of 6m......Field margin management for conservation purposes is a way to protect both functional biodiversity and biodiversity per se without considerable economical loss as field margins are less productive. However, the effect of width of the buffer zone on achievable biodiversity gains has received little...... was the narrowest that consistently promoted a higher abundance or activity of arthropods within the field area (outside the hedge bottom). However, a further increase in buffer width always increased the abundance and activity of arthropods a little more....

  13. Estimating the Spectral Width of a Narrowband Optical Signal

    DEFF Research Database (Denmark)

    Lading, Lars; Skov Jensen, A.

    1980-01-01

    Methods for estimating the spectral width of a narrowband optical signal are investigated. Spectral analysis and Fourier spectroscopy are compared. Optimum and close-to-optimum estimators are developed under the constraint of having only one photodetector.......Methods for estimating the spectral width of a narrowband optical signal are investigated. Spectral analysis and Fourier spectroscopy are compared. Optimum and close-to-optimum estimators are developed under the constraint of having only one photodetector....

  14. SM Higgs decay branching ratios and total Higgs width

    CERN Multimedia

    Daniel Denegri

    2001-01-01

    Upper: Higgs decay ratios as a function of Higgs mass. The largest branching ratio is not necessarily the most usefull one. The most usefull ones are gamma gamma bbar ZZ and WW as in those modes latter signal to background ratios can be achieved. Lower: Total Higgs decay width versus Higgs mass. At low masses the natural width is extremely small, thus observability depends on instrumental resolution primarily.

  15. Study of partial width fluctuations for 232Th radiative capture

    International Nuclear Information System (INIS)

    Nifenecker, H.; Hazoni, Y.; Michaudon, A.; Paya, D.

    1962-01-01

    The partial widths of radiative capture at the excited level at 1 MeV in 233 Th were measured. This measurement was achieved on 7 neutron resonances of 232 Th from 20 to 175 eV. The normalization methods used for deducing these widths are described. The most probable value of the number of degrees of freedom is found to be 4 and the probability that ν ≤ 1 is found to be 16 per cent. (authors) [fr

  16. Width of electromagnetic wave instability spectrum in tungsten plate

    International Nuclear Information System (INIS)

    Rinkevich, A.B.

    1995-01-01

    Based on the study of high-frequency signal modulation and spectrum analysis of the envelope a measurement of spectrum width for electromagnetic wave instability was carried out under conditions of current pulse action on tungsten plate in magnetic field. The existence of amplitude-frequency wave modulation was revealed. The width of current disturbance spectrum in a specimen was evaluated. Current disturbances are shown to cause the instability of electromagnetic wave. 11 refs.; 6 figs

  17. Quantum numbers and decay widths of the psi (3684)

    International Nuclear Information System (INIS)

    Luth, V.; Boyarski, A.M.; Lynch, H.L.; Breidenbach, M.; Bulos, F.; Feldman, G.J.; Fryberger, D.; Hanson, G.; Hartill, D.L.; Jean-Marie, B.; Larsen, R.R.; Luke, D.; Morehouse, C.C.; Paterson, J.M.; Perl, M.L.; Pun, T.P.; Rapidis, P.; Richter, B.; Schwitters, R.F.; Tanenbaum, W.; Vannucci, F.; Abrams, G.S.; Chinowsky, W.; Friedberg, C.E.; Goldhaber, G.; Kadyk, J.A.; Litke, A.M.; Lulu, B.A.; Pierre, F.M.; Sadoulet, B.; Trilling, G.H.; Whitaker, J.S.; Winkelmann, F.C.; Wiss, J.E.

    1975-01-01

    Cross sections for e + e - →hadrons, e + e - , and μ + μ - near 3684 MeV are presented. The psi(3684) resonance is established as having the assignment J/sup PC/=1 -- . The mass is 3684+-5 MeV. The partial width for decay to electrons is GAMMA/sube/=2.1+-0.3 keV and the total width is GAMMA=228+-56 keV

  18. Correlations for reduced-width amplitudes in 49V

    International Nuclear Information System (INIS)

    Chou, B.H.; Mitchell, G.E.; Bilpuch, E.G.; Westerfeldt, C.R.

    1980-01-01

    Measurement of the relative sign of inelastic proton-channel amplitudes permits the determination of amplitude correlations. Data were obtained for 45 5/2 + resonances in 49 V. Although the reduced widths in each channel followed a Porter-Thomas distribution, large amplitude correlations were observed. The results are compared with the reduced-width--amplitude distribution of Krieger and Porter. This is the first direct test of the Krieger-Porter distribution

  19. Comprehensive intermaxillary tooth width proportion of Bangkok residents

    Directory of Open Access Journals (Sweden)

    Somchai Manopatanakul

    2011-04-01

    Full Text Available Proper occlusion depends on the correct width ratio between upper and lower teeth, known as Bolton's ratio. In fact, this ratio can be calculated for each pair of teeth from the central incisor to the first permanent molar. This set of ratios, known as comprehensive cumulative percentage ratios (CPRs, can be used not only to determine which tooth or teeth have a tooth width discrepancy, but can also enable the partial graphical analysis of tooth width discrepancy when there is agenesis of certain permanent teeth. Although CPRs have been calculated for Caucasians, tooth width is known to vary depending on racial origin. Therefore, a test of differences between racial groups should be carried out. If these ratios of the Caucasians and Bangkokians are significantly different, the ratio of the Bangkokians is recommended. The objective of this study was to measure tooth size disproportion for Thai patients and to calculate a corresponding set of CPRs. Thirty-seven pairs of dental models were made from a group of Bangkok residents with normal occlusion. Mesiodistal tooth width was measured for each model. The intra- and inter-examiner measurement errors were ascertained as insignificant (p > 0.05. CPRs were then calculated and compared to those derived from other studies. Ten of thirteen CPRs were significantly different from corresponding values derived from Caucasians. We conclude that tooth width ratios vary between different racial groups, and therefore that these should be calculated specifically for each patient racial group.

  20. Stieltjes-moment-theory technique for calculating resonance width's

    International Nuclear Information System (INIS)

    Hazi, A.U.

    1978-12-01

    A recently developed method for calculating the widths of atomic and molecular resonances is reviewed. The method is based on the golden-rule definition of the resonance width, GAMMA(E). The method uses only square-integrable, L 2 , basis functions to describe both the resonant and the non-resonant parts of the scattering wave function. It employs Stieltjes-moment-theory techniques to extract a continuous approximation for the width discrete representation of the background continuum. Its implementation requires only existing atomic and molecular structure codes. Many-electron effects, such as correlation and polarization, are easily incorporated into the calculation of the width via configuration interaction techniques. Once the width, GAMMA(E), has been determined, the energy shift can be computed by a straightforward evaluation of the required principal-value integral. The main disadvantage of the method is that it provides only the total width of a resonance which decays into more than one channel in a multichannel problem. A review of the various aspects of the theory is given first, and then representative results that have been obtained with this method for several atomic and molecular resonances are discussed. 28 references, 3 figures, 4 tables

  1. Intensity dependence narrowing of electromagnetically induced absorption in a Doppler-broadened medium

    International Nuclear Information System (INIS)

    Dimitrijevic, J.; Arsenovic, D.; Jelenkovic, B. M.

    2007-01-01

    In this paper, we present a theoretical model for studying the interaction between linearly polarized laser light and near-degenerated Zeeman sublevels for a multiple V-type atomic system of 2 S 1/2 F g =2→ 2 P 3/2 F e =3 transition in 87 Rb. We have calculated the laser absorption in a Hanle configuration, as well as the amplitudes and the widths of electromagnetically induced absorption (EIA) in the range of laser intensities from 0.01 to 40 mW/cm 2 . Our results, showing nonvanishing EIA amplitude, a nonmonotonic increase of the EIA width for the increase of laser intensity, and pronounced shape differences of the Hanle EIA curves at different laser intensities, are in good agreement with recent experimental results. We have found that the EIA behaves differently than the electromagnetically induced transparency (EIT) as a function of the laser intensity. Both the amplitude and width of the EIA have narrow maximums at 1 to 2 mW/cm 2 . We have shown the strong influence of Doppler broadening of atomic transition on Hanle resonances and have suggested the explanation of it

  2. Turbulent energy dissipation rates observed by Doppler MST Radar and by rocket-borne instruments during the MIDAS/MaCWAVE campaign 2002

    Directory of Open Access Journals (Sweden)

    N. Engler

    2005-06-01

    Full Text Available During the MIDAS/MaCWAVE campaign in summer 2002 we have observed turbulence using Doppler beam steering measurements obtained from the ALWIN VHF radar at Andøya/Northern Norway. This radar was operated in the Doppler beam steering mode for turbulence investigations during the campaign, as well as in spaced antenna mode, for continuously measuring the background wind field. The real-time data analysis of the Doppler radar backscattering provided the launch conditions for the sounding rockets. The spectral width data observed during the occurrence of PMSE were corrected for beam and shear broadening caused by the background wind field to obtain the turbulent part of the spectral width. The turbulent energy dissipation rates determined from the turbulent spectral width vary between 5 and 100mW kg-1 in the altitude range of 80-92km and increase with altitude. These estimations agree well with the in-situ measurements using the CONE sensor which was launched on 3 sounding rockets during the campaign.

  3. Turbulent energy dissipation rates observed by Doppler MST Radar and by rocket-borne instruments during the MIDAS/MaCWAVE campaign 2002

    Directory of Open Access Journals (Sweden)

    N. Engler

    2005-06-01

    Full Text Available During the MIDAS/MaCWAVE campaign in summer 2002 we have observed turbulence using Doppler beam steering measurements obtained from the ALWIN VHF radar at Andøya/Northern Norway. This radar was operated in the Doppler beam steering mode for turbulence investigations during the campaign, as well as in spaced antenna mode, for continuously measuring the background wind field. The real-time data analysis of the Doppler radar backscattering provided the launch conditions for the sounding rockets. The spectral width data observed during the occurrence of PMSE were corrected for beam and shear broadening caused by the background wind field to obtain the turbulent part of the spectral width. The turbulent energy dissipation rates determined from the turbulent spectral width vary between 5 and 100mW kg-1 in the altitude range of 80-92km and increase with altitude. These estimations agree well with the in-situ measurements using the CONE sensor which was launched on 3 sounding rockets during the campaign.

  4. NARROW-LINE-WIDTH UV BURSTS IN THE TRANSITION REGION ABOVE SUNSPOTS OBSERVED BY IRIS

    Energy Technology Data Exchange (ETDEWEB)

    Hou, Zhenyong; Huang, Zhenghua; Xia, Lidong; Li, Bo; Madjarska, Maria S.; Fu, Hui; Mou, Chaozhou; Xie, Haixia, E-mail: z.huang@sdu.edu.cn, E-mail: xld@sdu.edu.cn [Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment, Institute of Space Sciences, Shandong University, Weihai, 264209 Shandong (China)

    2016-10-01

    Various small-scale structures abound in the solar atmosphere above active regions, playing an important role in the dynamics and evolution therein. We report on a new class of small-scale transition region structures in active regions, characterized by strong emissions but extremely narrow Si iv line profiles as found in observations taken with the Interface Region Imaging Spectrograph (IRIS). Tentatively named as narrow-line-width UV bursts (NUBs), these structures are located above sunspots and comprise one or multiple compact bright cores at sub-arcsecond scales. We found six NUBs in two data sets (a raster and a sit-and-stare data set). Among these, four events are short-lived with a duration of ∼10 minutes, while two last for more than 36 minutes. All NUBs have Doppler shifts of 15–18 km s{sup −1}, while the NUB found in sit-and-stare data possesses an additional component at ∼50 km s{sup −1} found only in the C ii and Mg ii lines. Given that these events are found to play a role in the local dynamics, it is important to further investigate the physical mechanisms that generate these phenomena and their role in the mass transport in sunspots.

  5. Narrow-line-width UV Bursts in the Transition Region above Sunspots Observed by IRIS

    Science.gov (United States)

    Hou, Zhenyong; Huang, Zhenghua; Xia, Lidong; Li, Bo; Madjarska, Maria S.; Fu, Hui; Mou, Chaozhou; Xie, Haixia

    2016-10-01

    Various small-scale structures abound in the solar atmosphere above active regions, playing an important role in the dynamics and evolution therein. We report on a new class of small-scale transition region structures in active regions, characterized by strong emissions but extremely narrow Si IV line profiles as found in observations taken with the Interface Region Imaging Spectrograph (IRIS). Tentatively named as narrow-line-width UV bursts (NUBs), these structures are located above sunspots and comprise one or multiple compact bright cores at sub-arcsecond scales. We found six NUBs in two data sets (a raster and a sit-and-stare data set). Among these, four events are short-lived with a duration of ˜10 minutes, while two last for more than 36 minutes. All NUBs have Doppler shifts of 15-18 km s-1, while the NUB found in sit-and-stare data possesses an additional component at ˜50 km s-1 found only in the C II and Mg II lines. Given that these events are found to play a role in the local dynamics, it is important to further investigate the physical mechanisms that generate these phenomena and their role in the mass transport in sunspots.

  6. Recommendations for terminology and display for doppler echocardiography

    International Nuclear Information System (INIS)

    Anon.

    1986-01-01

    Doppler echocardiography has recently emerged as a major noninvasive technique with many applications in cardiology. To a large extent, this has been based upon a combination of clinical and engineering advances which now make possible the use of quantitative Doppler echocardiography in combination with two-dimensional imaging for measurement of volume flows, transvalve gradients, and other physiologic flow parameters which reflect cardiac function. It was the purpose of this Committee to provide a glossary of terms which could be used in standard fashion for papers and discussions related to Doppler echocardiography. As part of its task, the Committee also undertook an attempt to recommend a standard for display of Doppler information which would be useful, both for manufacturers and for clinicians. The document, therefore, includes: Section I, the Committee's recommendations for Doppler display. Section II, the glossary of Doppler terms, related to engineering and to clinical applications

  7. Baroreflex regulation measurement using a noninvasive laser Doppler method

    Science.gov (United States)

    Hast, Jukka T.; Myllylae, Risto A.; Sorvoja, Hannu; Nissilae, Seppo M.

    2001-05-01

    In this study, a noninvasive laser Doppler measurement method based on the self-mixing effect of a diode laser was used to measure baroreflex regulation, which is manifest in the blood pressure signal as a 0.1 Hz sinusoidal variation. The laser Doppler measurement system was used to measure the movement of the right radial artery of ten volunteers. Variation in blood pressure caused by the baroreflex affects the elastic properties of the arterial wall. When diastolic blood pressure increases, the elasticity of the arterial wall decreases, causing the wall to lose some of its movability. This decreased elasticity reveals itself in the Doppler signal such that when the blood pressure increases, the Doppler frequency decreases and vice versa. The results show, that the laser Doppler method can be used to measure baroreflex regulation. Finally, baroreflex regulation in the Doppler signal is approximately in the inverse phase with respect to variation in diastolic blood pressure.

  8. Pulse Width Affects Scalp Sensation of Transcranial Magnetic Stimulation.

    Science.gov (United States)

    Peterchev, Angel V; Luber, Bruce; Westin, Gregory G; Lisanby, Sarah H

    Scalp sensation and pain comprise the most common side effect of transcranial magnetic stimulation (TMS), which can reduce tolerability and complicate experimental blinding. We explored whether changing the width of single TMS pulses affects the quality and tolerability of the resultant somatic sensation. Using a controllable pulse parameter TMS device with a figure-8 coil, single monophasic magnetic pulses inducing electric field with initial phase width of 30, 60, and 120 µs were delivered in 23 healthy volunteers. Resting motor threshold of the right first dorsal interosseus was determined for each pulse width, as reported previously. Subsequently, pulses were delivered over the left dorsolateral prefrontal cortex at each of the three pulse widths at two amplitudes (100% and 120% of the pulse-width-specific motor threshold), with 20 repetitions per condition delivered in random order. After each pulse, subjects rated 0-to-10 visual analog scales for Discomfort, Sharpness, and Strength of the sensation. Briefer TMS pulses with amplitude normalized to the motor threshold were perceived as slightly more uncomfortable than longer pulses (with an average 0.89 point increase on the Discomfort scale for pulse width of 30 µs compared to 120 µs). The sensation of the briefer pulses was felt to be substantially sharper (2.95 points increase for 30 µs compared to 120 µs pulse width), but not stronger than longer pulses. As expected, higher amplitude pulses increased the perceived discomfort and strength, and, to a lesser degree the perceived sharpness. Our findings contradict a previously published hypothesis that briefer TMS pulses are more tolerable. We discovered that the opposite is true, which merits further study as a means of enhancing tolerability in the context of repetitive TMS. Copyright © 2016 Elsevier Inc. All rights reserved.

  9. 2.5 MHz Line-Width High-energy, 2 Micrometer Coherent Wind Lidar Transmitter

    Science.gov (United States)

    Petros, Mulugeta; Yu, Jirong; Trieu, Bo; Bai, Yingxin; Petzar, Paul; Singh, Upendra N.; Reithmaier, Karl

    2007-01-01

    2 micron solid-state lasers are the primary choice for coherent Doppler wind detection. As wind lidars, they are used for wake vortex and clear air turbulence detection providing air transport safety. In addition, 2 micron lasers are one of the candidates for CO2 detection lidars. The rich CO2 absorption line around 2 micron, combined with the long upper state life of time, has made Ho based 2 micron lasers a viable candidate for CO2 sensing DIAL instrument. The design and fabrication of a compact coherent laser radar transmitter for Troposphere wind sensing is under way. This system is hardened for ground as well as airborne applications. As a transmitter for a coherent wind lidar, this laser has stringent spectral line width and beam quality requirements. Although the absolute wavelength does not have to be fixed for wind detection, to maximize return signal, the output wavelength should avoid atmospheric CO2 and H2O absorption lines. The base line laser material is Ho:Tm:LuLF which is an isomorph of Ho:Tm:YLF. LuLF produces 20% more output power than Ho:Tm:YLF. In these materials the Tm absorption cross-section, the Ho emission cross-section, the Tm to Ho energy transfer parameters and the Ho (sup 5) I (sub 7) radiative life time are all identical. However, the improved performance of the LuLF is attributed to the lower thermal population in the (sup 5) I (sub 8) manifold. It also provides higher normal mode to Q-switch conversion than YLF at high pump energy indicating a lower up-conversion. The laser architecture is composed of a seed laser, a ring oscillator, and a double pass amplifier. The seed laser is a single longitudinal mode with a line width of 13 KHz. The 100mJ class oscillator is stretched to 3 meters to accommodate the line-width requirement without compromising the range resolution of the instrument. The amplifier is double passed to produce greater than 300mJ energy.

  10. New Insights from Inside-Out Doppler Tomography

    Directory of Open Access Journals (Sweden)

    E. J. Kotze

    2015-02-01

    Full Text Available We present preliminary results from our investigation into using an “inside-out” velocity space for creating a Doppler tomogram. The aim is to transpose the inverted appearance of the Cartesian velocity space used in normal Doppler tomography. In a comparison between normal and inside-out Doppler tomograms of cataclysmic variables, we show that the inside-out velocity space has the potential to produce new insights into the accretion dynamics in these systems.

  11. Diagnostic value of Doppler echocardiography for identifying hemodynamic significant pulmonary valve regurgitation in tetralogy of Fallot: comparison with cardiac MRI.

    Science.gov (United States)

    Beurskens, Niek E G; Gorter, Thomas M; Pieper, Petronella G; Hoendermis, Elke S; Bartelds, Beatrijs; Ebels, Tjark; Berger, Rolf M F; Willems, Tineke P; van Melle, Joost P

    2017-11-01

    Quantification of pulmonary regurgitation (PR) is essential in the management of patients with repaired tetralogy of Fallot (TOF). We sought to evaluate the accuracy of first-line Doppler echocardiography in comparison with cardiac magnetic resonance imaging (MRI) to identify hemodynamic significant PR. Paired cardiac MRI and echocardiographic studies (n = 97) in patients with repaired TOF were retrospectively analyzed. Pressure half time (PHT) and pulmonary regurgitation index (PRi) were measured using continuous wave Doppler. The ratio of the color flow Doppler regurgitation jet width to pulmonary valve (PV) annulus (jet/annulus ratio) and diastolic to systolic time velocity integral (DSTVI; pulsed wave Doppler) were assessed. Accuracy of echocardiographic measurements was tested to identify significant PR as determined by phase-contrast MRI (PR fraction [PRF] ≥ 20%). Mean PRF was 29.4 ± 15.7%. PHT < 100 ms had a sensitivity of 93%, specificity 75%, positive predictive value (PPV) 92% and negative predictive value (NPV) 78% for identifying significant PR (C-statistic 0.82). PRi < 0.77 had sensitivity and specificity of 66% and 54%, respectively (C-statistic 0.63). Jet/annulus ratio ≥1/3 had sensitivity 96%, specificity 75%, PPV 92% and NPV 82% (C-statistic 0.87). DSTVI had sensitivity 84%, specificity 33%, PPV 84% and NPV 40%, (C-statistic 0.56). Combined jet/annulus ratio ≥1/3 and PHT < 100 ms was highly accurate in identifying PRF ≥ 20%, with sensitivity 97% and specificity 100%. PHT and jet/annulus ratio on Doppler echocardiography, especially when combined, are highly accurate in identifying significant PR and therefore seem useful in the follow-up of patients with repaired TOF.

  12. Power doppler 'blanching' after the application of transducer pressure

    International Nuclear Information System (INIS)

    Joshua, F.; Edmonds, J.; Lassere, M.; De Carle, R.; Rayment, M.; Bryant, C.; Shnier, R.

    2005-01-01

    The aim of this study was to determine if transducer pressure modifies power Doppler assessments of rheumatoid arthritis synovium at the metacarpophalangeal joints and metatarsophalangeal joints. Five rheumatoid arthritis patients of varying degrees of 'disease activity' and damage were assessed with power Doppler ultrasound scanning of the dominant hand second to fifth metacarpophalangeal joints. Two rheumatoid arthritis patients had their dominant foot first to fifth metatarsophalangeal joints assessed with power Doppler ultrasound. Ultrasonography was performed with a high frequency transducer (14 MHz) with a colour mode frequency of 10 Mhz, and a standard colour box and gain. In the joint that showed the highest power Doppler signal, an image was made. A further image was taken after transducer pressure was applied. In all patients, there was increased flow to at least one joint. After pressure was applied, power Doppler signal intensity markedly reduced in all images and in some there was no recordable power Doppler signal. Increased transducer pressure can result in a marked reduction or obliteration in power Doppler signal. This power Doppler 'blanching' shows the need for further studies to evaluate sources of error and standardization before power Doppler ultrasound becomes a routine measure of 'disease activity' in rheumatoid arthritis. Copyright (2005) Blackwell Science Pty Ltd

  13. EUV Doppler Imaging for CubeSat Platforms Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Mature the design and fabricate the Flare Initiation Doppler Imager (FIDI) instrument to demonstrate low-spacecraft-resource EUV technology (most notably,...

  14. Capacitor charging FET switcher with controller to adjust pulse width

    Science.gov (United States)

    Mihalka, Alex M.

    1986-01-01

    A switching power supply includes an FET full bridge, a controller to drive the FETs, a programmable controller to dynamically control final output current by adjusting pulse width, and a variety of protective systems, including an overcurrent latch for current control. Power MOSFETS are switched at a variable frequency from 20-50 kHz to charge a capacitor load from 0 to 6 kV. A ferrite transformer steps up the DC input. The transformer primary is a full bridge configuration with the FET switches and the secondary is fed into a high voltage full wave rectifier whose output is connected directly to the energy storage capacitor. The peak current is held constant by varying the pulse width using predetermined timing resistors and counting pulses. The pulse width is increased as the capacitor charges to maintain peak current. A digital ripple counter counts pulses, and after the desired number is reached, an up-counter is clocked. The up-counter output is decoded to choose among different resistors used to discharge a timing capacitor, thereby determining the pulse width. A current latch shuts down the supply on overcurrent due to either excessive pulse width causing transformer saturation or a major bridge fault, i.e., FET or transformer failure, or failure of the drive circuitry.

  15. Burst Format Design for Optimum Joint Estimation of Doppler-Shift and Doppler-Rate in Packet Satellite Communications

    Directory of Open Access Journals (Sweden)

    Luca Giugno

    2007-05-01

    Full Text Available This paper considers the problem of optimizing the burst format of packet transmission to perform enhanced-accuracy estimation of Doppler-shift and Doppler-rate of the carrier of the received signal, due to relative motion between the transmitter and the receiver. Two novel burst formats that minimize the Doppler-shift and the Doppler-rate Cramér-Rao bounds (CRBs for the joint estimation of carrier phase/Doppler-shift and of the Doppler-rate are derived, and a data-aided (DA estimation algorithm suitable for each optimal burst format is presented. Performance of the newly derived estimators is evaluated by analysis and by simulation, showing that such algorithms attain their relevant CRBs with very low complexity, so that they can be directly embedded into new-generation digital modems for satellite communications at low SNR.

  16. Burst Format Design for Optimum Joint Estimation of Doppler-Shift and Doppler-Rate in Packet Satellite Communications

    Directory of Open Access Journals (Sweden)

    Zanier Francesca

    2007-01-01

    Full Text Available This paper considers the problem of optimizing the burst format of packet transmission to perform enhanced-accuracy estimation of Doppler-shift and Doppler-rate of the carrier of the received signal, due to relative motion between the transmitter and the receiver. Two novel burst formats that minimize the Doppler-shift and the Doppler-rate Cramér-Rao bounds (CRBs for the joint estimation of carrier phase/Doppler-shift and of the Doppler-rate are derived, and a data-aided (DA estimation algorithm suitable for each optimal burst format is presented. Performance of the newly derived estimators is evaluated by analysis and by simulation, showing that such algorithms attain their relevant CRBs with very low complexity, so that they can be directly embedded into new-generation digital modems for satellite communications at low SNR.

  17. Digital setup for Doppler broadening spectroscopy

    International Nuclear Information System (INIS)

    Cizek, J; Vlcek, M; Prochazka, I

    2011-01-01

    New digital spectrometer for measurement of the Doppler shift of annihilation photons was developed and tested in this work. Digital spectrometer uses a fast 12-bit digitizer for direct sampling of signals from HPGe detectors. Analysis of sampled waveforms is performed off-line in software. Performance of the new digital setup was compared with its traditional analogue counterpart. Superior energy resolution was achieved in the digital setup. Moreover, the digital setup allows for a better control of the shape of detector signals. This enables to eliminate undesired signals damaged by pile-up effects or by ballistic deficit.

  18. [Color Doppler sonography of focal abdominal lesions].

    Science.gov (United States)

    Licanin, Zoran; Lincender, Lidija; Djurović, V; Salihefendić, Nizama; Smajlović, Fahrudin

    2004-01-01

    Color Doppler sonography (CDS--spectral, color and power), harmonic imaging techniques (THI, PHI), possibility of 3D analysis of picture, usage of contrast agents, have raised the values of ultrasound as a diagnostic method to a very high level. THI--non-linear gray scale modality, is based on the processing of higher reflected frequencies, that has improved a picture resolution, which is presented with less artifacts and limiting effects of obesity and gases. Ultrasound contrast agents improve analysis of micro and macro circulation of the examined area, and with the assessment of velocity of supply in ROI (wash in), distribution and time of signal weakening (wash out), are significantly increasing diagnostic value of ultrasound. Besides the anatomical and topographic presentation of examined region (color, power), Color Doppler sonography gives us haemodynamic-functional information on vascularisation of that region, as well as on pathologic vascularisation if present. Avascular aspect of a focal pathologic lesion corresponds to a cyst or haematoma, while coloration and positive spectral curve discover that anechogenic lesions actually represents aneurysms, pseudoaneurysms or AVF. In local inflammatory lesion, abscess in an acute phase, CDS shows first increased, and then decreased central perfusion, while in a chronic phase, a pericapsular vascularisation is present. Contribution of CDS in differentiation of hepatic tumors (hemangioma, HCC and metastasis) is very significant. Central color dots along the peripheral blood vessels and the blush phenomenon are characteristics of capillary hemangioma, peritumoral vascular ring "basket" of HCC, and "detour" sign of metastasis. The central artery, RI from 0.45 to 0.60 and radial spreading characterize FNH. Hepatic adenoma is characterized by an intratumoral vein, and rarely by a vascular hallo. Further on, blood velocity in tumor defined by Color Doppler, distinguishes malignant from benign lesion, where 40 cm/s is a

  19. Mobile fiber-optic laser Doppler anemometer.

    Science.gov (United States)

    Stieglmeier, M; Tropea, C

    1992-07-20

    A laser Doppler anemometer (LDA) has been developed that combines the compactness and low power consumption of laser diodes and avalanche photodiodes with the flexibility and possibility of miniaturization by using fiber-optic probes. The system has been named DFLDA for laser diode fiber LDA and is especially suited for mobile applications, for example, in trains, airplanes, or automobiles. Optimization considerations of fiber-optic probes are put forward and several probe examples are described in detail. Measurement results from three typical applications are given to illustrate the use of the DFLDA. Finally, a number of future configurations of the DFLDA concept are discussed.

  20. Modelling the widths of fission observables in GEF

    Directory of Open Access Journals (Sweden)

    Schmidt K.-H.

    2013-03-01

    Full Text Available The widths of the mass distributions of the different fission channels are traced back to the probability distributions of the corresponding quantum oscillators that are coupled to the heat bath, which is formed by the intrinsic degrees of freedom of the fissioning system under the influence of pairing correlations and shell effects. Following conclusion from stochastic calculations of Adeev and Pashkevich, an early freezing due to dynamical effects is assumed. It is shown that the mass width of the fission channels in low-energy fission is strongly influenced by the zero-point motion of the corresponding quantum oscillator. The observed variation of the mass widths of the asymmetric fission channels with excitation energy is attributed to the energy-dependent properties of the heat bath and not to the population of excited states of the corresponding quantum oscillator.

  1. Form factors and radiation widths of the giant multipole resonances

    International Nuclear Information System (INIS)

    Denisov, V.Yu.

    1990-01-01

    Simple analytic relations for the form factors of inelastic electron scattering in the Born approximation and radiation widths of the isovector and isoscalar giant multipole resonances are derived. The dynamic relationship between the volume and surface density vibrations were taken into account in this calculation. The form factors in the Born approximation were found to be in satisfactory agreement with experimental data in the region of small transferred momenta. The radiation widths of isoscalar multipole resonances increase when the number of nucleons increase as A 1/3 , and for isovector resonances this dependence has the form f(A)A 1/3 , where f(A) is a slowly increasing function of A. Radiation widths well fit the experimental data

  2. Analysis of edge stability for models of heat flux width

    Directory of Open Access Journals (Sweden)

    M.A. Makowski

    2017-08-01

    Full Text Available Detailed measurements of the ne, Te, and Ti profiles in the vicinity of the separatrix of ELMing H-mode discharges have been used to examine plasma stability at the extreme edge of the plasma and assess stability dependent models of the heat flux width. The results are strongly contrary to the critical gradient model, which posits that a ballooning instability determines a gradient scale length related to the heat flux width. The results of this analysis are not sensitive to the choice of location to evaluate stability. Significantly, it is also found that the results are completely consistent with the heuristic drift model for the heat flux width. Here the edge pressure gradient scales with plasma density and is proportional to the pressure gradient inferred from the equilibrium in accordance with the predictions of that theory.

  3. Fast and Robust Nanocellulose Width Estimation Using Turbidimetry.

    Science.gov (United States)

    Shimizu, Michiko; Saito, Tsuguyuki; Nishiyama, Yoshiharu; Iwamoto, Shinichiro; Yano, Hiroyuki; Isogai, Akira; Endo, Takashi

    2016-10-01

    The dimensions of nanocelluloses are important factors in controlling their material properties. The present study reports a fast and robust method for estimating the widths of individual nanocellulose particles based on the turbidities of their water dispersions. Seven types of nanocellulose, including short and rigid cellulose nanocrystals and long and flexible cellulose nanofibers, are prepared via different processes. Their widths are calculated from the respective turbidity plots of their water dispersions, based on the theory of light scattering by thin and long particles. The turbidity-derived widths of the seven nanocelluloses range from 2 to 10 nm, and show good correlations with the thicknesses of nanocellulose particles spread on flat mica surfaces determined using atomic force microscopy. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Doppler ultrasound scan during normal gestation: umbilical circulation; Ecografia Doppler en la gestacion normal: circulacion umbilical

    Energy Technology Data Exchange (ETDEWEB)

    Ruiz, T.; Sabate, J.; Martinez-Benavides, M. M.; Sanchez-Ramos, J. [Hospital Virgen Macarena. Sevilla (Spain)

    2002-07-01

    To determine normal umbilical circulation patterns by means of Doppler ultrasound scan in a healthy gestating population without risk factors and with normal perinatal results, and to evaluate any occurring modifications relative to gestational age by obtaining records kept during pregnancy. One hundred and sixteen pregnant women carrying a single fetus have been studied. These women had no risk factors, with both clinical and analytical controls, as well as ultrasound scans, all being normal. There were performed a total of 193 Doppler ultrasound scans between weeks 15 and 41 of gestation, with blood-flow analysis in the arteries and vein of the umbilical cord. The obtained information was correlated with parameters that evaluate fetal well-being (fetal monitoring and/or oxytocin test) and perinatal result (delivery type, birth weight, Apgar score). Statistical analysis was performed with the programs SPSS 6.0.1 for Windows and EPIINFO 6.0.4. With pulsed Doppler, the umbilical artery in all cases demonstrated a biphasic morphology with systolic and diastolic components and without retrograde blood flow. As the gestation period increased, there was observed a progressive decrease in resistance along with an increase in blood-flow velocity during the diastolic phase. The Doppler ultrasound scan is a non-invasive method that permits the hemodynamic study of umbilical blood circulation. A knowledge of normal blood-flow signal morphology, as well as of the normal values for Doppler indices in relation to gestational age would permit us to utilize this method in high-risk pregnancies. (Author) 30 refs.

  5. Similarity of Stream Width Distributions Across Headwater Systems

    Science.gov (United States)

    Allen, G. H.; Pavelsky, T.; Barefoot, E. A.; Tashie, A.; Butman, D. E.

    2016-12-01

    The morphology and abundance of streams control the rates of hydraulic and biogeochemical exchange between streams, groundwater, and the atmosphere. In large river systems, studies have used remote sensing to quantify river morphology, and have found that the relationship between river width and abundance is fractal, such that narrow rivers are proportionally more common than wider rivers. However, in headwater systems (stream order 1-3), where many biogeochemical reactions are most rapid, the relationship between stream width and abundance is unknown, reducing the certainty of biogeochemical flux estimates. To constrain this uncertainty, we surveyed two components of stream morphology (wetted stream width and length) in seven physiographically contrasting stream networks in Kings Creek in Konza Prarie, KS; Sagehen Creek in the N. Sierra Nevada Mtns., CA; Elder Creek in Angelo Coast Range Preserve, CA; Caribou Creek in the Caribou Poker Creek Research Watershed, AK; V40 Stream, NZ; Blue Duck Creek, NZ; Stony Creek in Duke Forest, NC. To assess temporal variations, we also surveyed stream geometry in a subcatchment of Stony Creek six times over a range of moderate streamflow conditions (discharge less than 90 percentile of gauge record). Here we show a strikingly consistent gamma statistical distribution of stream width in all surveys and a characteristic most abundant stream width of 32±7 cm independent of flow conditions or basin size. This consistency is remarkable given the substantial physical diversity among the studied catchments. We propose a model that invokes network topology theory and downstream hydraulic geometry to show that, as active drainage networks expand and contract in response to changes in streamflow, the most abundant stream width remains approximately static. This framework can be used to better extrapolate stream size and abundance from large rivers to small headwater streams, with significant impact on understanding of the hydraulic

  6. Avaliação dos tumores hepáticos ao Doppler Doppler evaluation of liver tumors

    OpenAIRE

    Márcio Martins Machado; Ana Cláudia Ferreira Rosa; Paulo Herman; Nestor de Barros; Orlando Milhomem da Mota; Letícia Martins Azeredo; Osterno Queiroz da Silva; Jales Benevides Santana Filho; Paulo Moacir O. Campoli; Paulo Adriano Q. Barreto; Patrícia Medeiros Milhomem; Leonardo Medeiros Milhomem; Murilo Tavares Daher; Renato Tavares Daher; Luciana Mendes de Oliveira Cerri

    2004-01-01

    Os avanços recentes na ultra-sonografia têm ampliado a possibilidade de detecção de tumores hepáticos. Isto tem auxiliado na perspectiva de melhora do prognóstico destes pacientes, à medida que novas técnicas terapêuticas têm surgido. Neste artigo os autores relatam achados ao Doppler que podem auxiliar na identificação e caracterização dos tumores hepáticos, avaliando dados do Doppler colorido, pulsado e do Doppler de amplitude ("power Doppler"). Fazem, também, referência a novas modalidades...

  7. Diagnostic Technique of Neutron Doppler Broadening for Indirectly-Driven Implosions

    Science.gov (United States)

    Xiong, Yong; Ding, Yongkun; Zheng, Zhijian; Chen, Ming

    2004-06-01

    The neutron Doppler broadening in inertial confinement fusion has been acquired from the time of flight for the neutron, from which the fuel ion temperature can be derived. An ultrafast-quenched plastic scintillation detector was used to measure the time of flight for the neutron at a low-imploded DT neutron yield (5×107-1×108) in the experiment performed on the Shenguang II laser facility. The typical temperatures of ablating targets for indirect drive were around 2.8 keV and the uncertainties were ±30%-±40%. The detection efficiency of the detector for DT neutrons was calibrated at a K-400 accelerator. The time response function of the detection system was calibrated by imploded neutrons from a DT-filled capsule, which can be regarded as a δ function pulsed neutron source due to its much narrower pulse width than that of the measured neutron time-of-flight spectrum.

  8. Diagnostic technique of neutron doppler broadening for indirectly-driven implosions

    International Nuclear Information System (INIS)

    Xiong Yong; Ding Yongkun; Zheng Zhijian; Chen Ming

    2004-01-01

    The neutron Doppler broadening in inertial confinement fusion has been acquired from the time of flight for the neutron, from which the fuel ion temperature can be derived. An ultrafast-quenched plastic scintillation detector was used to measure the time of flight for the neutron at a low-imploded DT neutron yield (5 x 10 7 - 1 x 10 8 ) in the experiment performed on the Shenguang II laser facility. The typical temperatures of ablating targets for indirect drive were around 2.8 keV and the uncertainties were ±30%-±40%. The detection efficiency of the detector for DT neutrons was calibrated at a K-400 accelerator. The time response function of the detection system was calibrated by imploded neutrons from a DT-filled capsule, which can be regarded as a δ function pulsed neutron source due to its much narrower pulse width than that of the measured neutron time-of-flight spectrum. (authors)

  9. 1540-nm single frequency single-mode pulsed all fiber laser for coherent Doppler lidar

    Science.gov (United States)

    Zhang, Xin; Diao, Weifeng; Liu, Yuan; Liu, Jiqiao; Hou, Xia; Chen, Weibiao

    2015-02-01

    A single-mode single frequency eye-safe pulsed all fiber laser based on master oscillator power amplification structure is presented. This laser is composed of a narrow linewidth distributed laser diode seed laser and two-stage cascade amplifiers. 0.8 m longitudinally gradient strained erbium/ytterbium co-doped polarization-maintaining fiber with a core diameter of 10 μm is used as the gain fiber and two acoustic-optics modulators are adopted to enhance pulse extinction ratio. A peak power of 160 W and a pulse width of 200 ns at 10 kHz repetition rate are achieved with transform-limited linewidth and diffraction-limited beam quality. This laser will be employed in a compact short range coherent Doppler wind lidar.

  10. Total Space in Resolution Is at Least Width Squared

    OpenAIRE

    Bonacina, Ilario

    2016-01-01

    Given an unsatisfiable k-CNF formula phi we consider two complexity measures in Resolution: width and total space. The width is the minimal W such that there exists a Resolution refutation of phi with clauses of at most W literals. The total space is the minimal size T of a memory used to write down a Resolution refutation of phi where the size of the memory is measured as the total number of literals it can contain. We prove that T = Omega((W - k)^2).

  11. Statistical analysis of s-wave neutron reduced widths

    International Nuclear Information System (INIS)

    Pandita Anita; Agrawal, H.M.

    1992-01-01

    The fluctuations of the s-wave neutron reduced widths for many nuclei have been analyzed with emphasis on recent measurements by a statistical procedure which is based on the method of maximum likelihood. It is shown that the s-wave neutron reduced widths of nuclei follow single channel Porter Thomas distribution (x 2 -distribution with degree of freedom ν = 1) for most of the cases. However there are apparent deviations from ν = 1 and possible explanation and significance of this deviation is given. These considerations are likely to modify the evaluation of neutron cross section. (author)

  12. Efficient algorithms for estimating the width of nearly normal distributions

    International Nuclear Information System (INIS)

    Akerlof, C.W.

    1983-01-01

    Typical physics data samples often conform to Gaussian distributions with admixtures of more slowly varying backgrounds. Under such circumstances the standard deviation is known to be a poor statistical measure of distribution width. As an alternative, the performance of Gini's mean difference is compared with the standard deviation and the mean deviation. Variants which sum over subsets of all possible pairs are shown to have statistical efficiencies comparable to the mean difference and mean deviation but do not require extensive data storage or a priori knowledge of the sample mean. These statistics are reasonable candidates for monitoring the distribution width of a real time data stream. (orig.)

  13. S-Band Doppler Wave Radar System

    Directory of Open Access Journals (Sweden)

    Zezong Chen

    2017-12-01

    Full Text Available In this paper, a novel shore-based S-band microwave Doppler coherent wave radar (Microwave Ocean Remote SEnsor (MORSE is designed to improve wave measurements. Marine radars, which operate in the X band, have been widely used for ocean monitoring because of their low cost, small size and flexibility. However, because of the non-coherent measurements and strong absorption of X-band radio waves by rain, these radar systems suffer considerable performance loss in moist weather. Furthermore, frequent calibrations to modify the modulation transfer function are required. To overcome these shortcomings, MORSE, which operates in the S band, was developed by Wuhan University. Because of the coherent measurements of this sensor, it is able to measure the radial velocity of water particles via the Doppler effect. Then the relation between the velocity spectrum and wave height spectrum can be used to obtain the wave height spectra. Finally, wave parameters are estimated from the wave height spectra by the spectrum moment method. Comparisons between MORSE and Waverider MKIII are conducted in this study, and the results, including the non-directional wave height spectra, significant wave height and average wave period, are calculated and displayed. The correlation coefficient of the significant wave height is larger than 0.9, whereas that of the average wave period is approximately 0.4, demonstrating the effectiveness of MORSE for the continuous monitoring of ocean areas with high accuracy.

  14. Fusion of Telescopic and Doppler Radar Data

    Science.gov (United States)

    Navara, M.; Matousek, M.; Drbohlav, O.

    2014-09-01

    We study the possibilities of observations of satellites at circular LEO orbits simultaneously by a telescope and a bistatic continuous-wave Doppler radar. Telescopic images allow for trajectory determination except for its distance (and hence height). Assuming a circular orbit, the height can be computed from the angular speed, but this is often impossible for LEO objects which do not remain in the field of view during the whole exposure time. To restore the missing information, we use Doppler radar data from a radio astronomy network, originally designed for detection of meteors. Using simulated perturbations of real radar data we studied their influence on the estimates of (i) permanent parameters of trajectory (orbital elements), (ii) instantaneous parameters of trajectory, (iii) distance and height estimates if the other parameters are given by the telescopic data. We derived recommendations for the optimal positions of the transmitter and receivers leading to the best resolution. We also discuss possible ways of improvement of this technique. Fusion results are shown on a suite of several matched radar and telescopic satellite fly-over data.

  15. Improved Micro Rain Radar snow measurements using Doppler spectra post-processing

    Directory of Open Access Journals (Sweden)

    M. Maahn

    2012-11-01

    Full Text Available The Micro Rain Radar 2 (MRR is a compact Frequency Modulated Continuous Wave (FMCW system that operates at 24 GHz. The MRR is a low-cost, portable radar system that requires minimum supervision in the field. As such, the MRR is a frequently used radar system for conducting precipitation research. Current MRR drawbacks are the lack of a sophisticated post-processing algorithm to improve its sensitivity (currently at +3 dBz, spurious artefacts concerning radar receiver noise and the lack of high quality Doppler radar moments. Here we propose an improved processing method which is especially suited for snow observations and provides reliable values of effective reflectivity, Doppler velocity and spectral width. The proposed method is freely available on the web and features a noise removal based on recognition of the most significant peak. A dynamic dealiasing routine allows observations even if the Nyquist velocity range is exceeded. Collocated observations over 115 days of a MRR and a pulsed 35.2 GHz MIRA35 cloud radar show a very high agreement for the proposed method for snow, if reflectivities are larger than −5 dBz. The overall sensitivity is increased to −14 and −8 dBz, depending on range. The proposed method exploits the full potential of MRR's hardware and substantially enhances the use of Micro Rain Radar for studies of solid precipitation.

  16. A Rayleigh Doppler Frequency Estimator Derived from Maximum Likelihood Theory

    DEFF Research Database (Denmark)

    Hansen, Henrik; Affes, Sofiene; Mermelstein, Paul

    1999-01-01

    Reliable estimates of Rayleigh Doppler frequency are useful for the optimization of adaptive multiple access wireless receivers.The adaptation parameters of such receivers are sensitive to the amount of Doppler and automatic reconfiguration to the speed of terminalmovement can optimize cell capac...

  17. On acceleration dependence of Doppler effect in light

    Indian Academy of Sciences (India)

    Home; Journals; Pramana – Journal of Physics; Volume 81; Issue 3. On acceleration dependence of ... Using only the geometric relationships of suitable locations, we analyse Doppler effect in light to show how the acceleration of the source also contributes to the Doppler shift. We further propose that an experiment be ...

  18. Normal Foetal Middle Cerebral Arteries Doppler Velocimetry; Study ...

    African Journals Online (AJOL)

    Doppler assessment of the middle cerebral artery (MCA) is one method of evaluating foetus before delivery and can determine foetuses at risk in high risk pregnancies. This study was done to determine the normal reference values of foetal middle cerebral artery Doppler indices in our population. One hundred and forty ...

  19. Umbilical artery doppler velocimetry study on prediction of adverse ...

    African Journals Online (AJOL)

    Background: Doppler velocimetry studies of pregnant women with diabetes mellitus can predict adverse pregnancy outcomes. Objective: To identify pregnant women with diabetes mellitus for second trimester umbilical artery Doppler velocimetry to predict adverse pregnancy outcomes. Methods: It was a prospective study ...

  20. Detection and visualization to Doppler sensitive sonar pulses

    NARCIS (Netherlands)

    Bertrand, D.B.; IJsselmuide, S.P. van; Beerens, S.P.

    2006-01-01

    In anti-submarine warfare, the use of Doppler sensitive sonar pulses is common practice. In particular, the wideband Doppler sensitive PTFM pulse (Pulse Train Frequency Modulation) is a powerful tool for detection in reverberation limited conditions. Nevertheless, this pulse is not operationally

  1. Correlation between Spectral Index and Doppler Factor for a ...

    Indian Academy of Sciences (India)

    Abstract. Relativistic beaming effect is important for blazars. In a very recent work, γ-ray Doppler factors were calculated for a sample of Fermi blazars (Fan et al. 2013). In this work, we investigated the correlation between the Doppler factor and the effective spectral index, αOX, and found an anticorrelation between them.

  2. Optical Doppler tomography based on a field programmable gate array

    DEFF Research Database (Denmark)

    Larsen, Henning Engelbrecht; Nilsson, Ronnie Thorup; Thrane, Lars

    2008-01-01

    We report the design of and results obtained by using a field programmable gate array (FPGA) to digitally process optical Doppler tomography signals. The processor fits into the analog signal path in an existing optical coherence tomography setup. We demonstrate both Doppler frequency and envelope...

  3. Musculoskeletal colour/power Doppler in sports medicine

    DEFF Research Database (Denmark)

    Boesen, M I; Boesen, M; Langberg, Henning

    2010-01-01

    This review article discusses the aspects of sports medicine where musculoskeletal Doppler ultrasound has valuable contribution in diagnosis and/or treatment of some of the typical musculoskeletal sports injuries. Also, conditions where the Doppler ultrasound has no value are discussed. Some guid...

  4. Doppler weather radar with predictive wind shear detection capabilities

    Science.gov (United States)

    Kuntman, Daryal

    1991-01-01

    The status of Bendix research on Doppler weather radar with predictive wind shear detection capability is given in viewgraph form. Information is given on the RDR-4A, a fully coherent, solid state transmitter having Doppler turbulence capability. Frequency generation data, plans, modifications, system characteristics and certification requirements are covered.

  5. CAMEX-4 ER-2 DOPPLER RADAR V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The ER-2 Doppler radar (EDOP) is an X-band (9.6 GHz) Doppler radar mounted in the nose of ER-2. The instrument has two fixed antennas, one pointing at nadir and the...

  6. Power and color Doppler ultrasound settings for inflammatory flow

    DEFF Research Database (Denmark)

    Torp-Pedersen, Søren; Christensen, Robin; Szkudlarek, Marcin

    2015-01-01

    OBJECTIVE: To determine how settings for power and color Doppler ultrasound sensitivity vary on different high- and intermediate-range ultrasound machines and to evaluate the impact of these changes on Doppler scoring of inflamed joints. METHODS: Six different types of ultrasound machines were us...

  7. The effectiveness of Doppler controlled hemorrhoidal artery ligation ...

    African Journals Online (AJOL)

    In this work, we discuss the preliminary results of the effectiveness of the hemorrhoidal artery ligation under control Doppler as a new technique for the treatment of hemorrhoids. We report the results of patients with hemorrhoids we have followed over a period of one year who were treated with HAL Doppler. The intra-and ...

  8. Musculoskeletal colour/power Doppler in sports medicine

    DEFF Research Database (Denmark)

    Boesen, M I; Boesen, M; Langberg, Henning

    2010-01-01

    This review article discusses the aspects of sports medicine where musculoskeletal Doppler ultrasound has valuable contribution in diagnosis and/or treatment of some of the typical musculoskeletal sports injuries. Also, conditions where the Doppler ultrasound has no value are discussed. Some...

  9. Experience in scrotal doppler ultrasound in a Nigerian tertiary hospital

    African Journals Online (AJOL)

    Background: Scrotal diseases can be diagnosed with clinical examination or radiological imaging. The use of ultrasound with Doppler application has several advantages in the evaluation of this sensitive and private organ. Objectives: To document the pattern of Doppler ultrasound findings in patients presenting with ...

  10. Distribution of Doppler Redshifts of Associated Absorbers of SDSS ...

    Indian Academy of Sciences (India)

    2016-01-27

    Jan 27, 2016 ... Doppler redshifts of a sample of Mg II associated absorbers of SDSS DR7 quasars are analysed. We find that there might be three Gaussian components in the distribution of the Doppler redshift. The first Gaussian component, with the peak being located at Dopp = -0.0074, probably arises from absorbers ...

  11. Methodology for obtaining wind gusts using Doppler lidar

    DEFF Research Database (Denmark)

    Suomi, Irene; Gryning, Sven-Erik; O'Connor, Ewan J.

    2017-01-01

    A new methodology is proposed for scaling Doppler lidar observations of wind gusts to make them comparable with those observed at a meteorological mast. Doppler lidars can then be used to measure wind gusts in regions and heights where traditional meteorological mast measurements are not availabl...

  12. A Rayleigh Doppler frequency estimator derived from maximum likelihood theory

    DEFF Research Database (Denmark)

    Hansen, Henrik; Affes, Sofiéne; Mermelstein, Paul

    1999-01-01

    Reliable estimates of Rayleigh Doppler frequency are useful for the optimization of adaptive multiple access wireless receivers. The adaptation parameters of such receivers are sensitive to the amount of Doppler and automatic reconfiguration to the speed of terminal movement can optimize cell cap...

  13. Downstream flow top width prediction in a river system | Choudhury ...

    African Journals Online (AJOL)

    ANFIS, ARIMA and Hybrid Multiple Inflows Muskingum models (HMIM) were applied to simulate and forecast downstream discharge and flow top widths in a river system. The ANFIS model works on a set of linguistic rules while the ARIMA model uses a set of past values to predict the next value in a time series. The HMIM ...

  14. Crack width analysis of steel fibers reinforced concrete beams

    Directory of Open Access Journals (Sweden)

    Šahinagić-Isović Merima

    2017-01-01

    Full Text Available Fibre reinforced concrete in recent years has grown from experimental material to a practical usable material, due to its positive properties such as increased tensile strength, bending strength, toughness etc. However, still there are many unanswered questions that are the subject of many research. In this paper results and analysis of crack width of concrete beams with steel fibres are presented. This analysis considers influence of steel fibre addition on the crack width of reinforced concrete beams (dimensions 15/28/300 cm loaded up to fracture during short-term ultimate static load with one unloading cycle. Concrete beams were made of two types of concrete: ordinary strength concrete (OSC - C30/37 and high strength concrete (HSC - C60/70, with and without 0.45% of steel fibres. The results indicate that there is a significant influence of fibre addition on crack width, especially for ordinary concrete. At the end, empirical calculations of the concrete elements' crack width with steel fibres according to the recommendations of RILEM and ACI building code are given.

  15. Detonation cell widths in hydrogen-air-diluent mixtures

    International Nuclear Information System (INIS)

    Stamps, D.W.

    1990-01-01

    In this paper I report on the influence of steam and carbon dioxide on the detonability of hydrogen-air mixtures. Data were obtained on the detonation cell width in a heated detonation tube that is 0.43 m in diameter and 13.1 m long. The detonation cell widths were correlated using a characteristic length calculated from a chemical kinetic model. The addition of either diluent to a hydrogen-air mixture increased the cell width for all equivalence ratios. For equal diluent concentrations, however, carbon dioxide not only yielded larger increases in the cell width than steam, but its efficacy relative to steam was predicted to increase with increasing concentration. The range of detonable hydrogen concentrations in a hydrogen-air mixture initially at 1 atm pressure was found to be between 11.6 percent and 74.9 percent for mixtures at 20 degree C and 9.4 percent and 76.9 percent for mixtures at 100 degree C. The detonation limit was between 38.8 percent and 40.5 percent steam for a stoichiometric hydrogen-air-steam mixture initially at 100 degree C and 1 atm. 10 refs., 4 figs., 1 tab

  16. Prediction of concentrated flow width in ephemeral gully channels

    Science.gov (United States)

    Nachtergaele, J.; Poesen, J.; Sidorchuk, A.; Torri, D.

    2002-07-01

    Empirical prediction equations of the form W = aQb have been reported for rills and rivers, but not for ephemeral gullies. In this study six experimental data sets are used to establish a relationship between channel width (W, m) and flow discharge (Q, m3 s-1) for ephemeral gullies formed on cropland. The resulting regression equation (W = 2·51 Q0·412; R2 = 0·72; n = 67) predicts observed channel width reasonably well. Owing to logistic limitations related to the respective experimental set ups, only relatively small runoff discharges (i.e. Q channel width was attributed to a calculated peak runoff discharge on sealed cropland, the application field of the regression equation was extended towards larger discharges (i.e. 5 × 10channels revealed that the discharge exponent (distribution over the wetted perimeter between rills, gullies and rivers, (ii) a decrease in probability of a channel formed in soil material with uniform erosion resistance from rills over gullies to rivers and (iii) a decrease in average surface slope from rills over gullies to rivers.channel width equation for concentrated flow on cropland. For the frozen soils the equation

  17. Echo width of foam supports used in scattering measurements

    DEFF Research Database (Denmark)

    Appel-Hansen, Jørgen; Solodukhov, V. V.

    1979-01-01

    Theoretically and experimentally determined echo widths of dielectric cylinders having circular, triangular, and quadratic cross sections have been compared. The cylinders were made of foam material having a relative dielectric constant of about 1.035. The purpose of the investigation was to find...

  18. Joint space width in dysplasia of the hip

    DEFF Research Database (Denmark)

    Jacobsen, Steffen; Sonne-Holm, Stig; Søballe, K

    2005-01-01

    . Neither subjects with dysplasia nor controls had radiological signs of ongoing degenerative disease at admission. The primary radiological discriminator of degeneration of the hip was a change in the minimum joint space width over time. There were no significant differences between these with dysplasia...

  19. Femoral Intercondylar Notch (ICN) width in Nigerians: Its ...

    African Journals Online (AJOL)

    It is suggested that the difference could be the result of dominant use of one foot over the other or to occupational habit. This needs further investigation. The Femoral Intercondylar Notch (ICN) width is not related to Femur length as no relationship was found to exist between the two (p > 0.05). We conclude that since ...

  20. Utility Interfaced Pulse-Width Modulation of Solar Fed Voltage ...

    African Journals Online (AJOL)

    This paper describes a utility interfaced pulse-width modulation of solar-fed voltage source single phase full bridge inverter. The proposed system has to do with the conversion of solar energy into electrical energy; boosting the dc power; inversion of the dc to ac and then synchronization of the inverter output with the utility, ...

  1. Frequency width of open channels in multiple scattering media

    NARCIS (Netherlands)

    Bosch, J.; Goorden, S.A.; Mosk, Allard

    2016-01-01

    We report optical measurements of the spectral width of open transmission channels in a three-dimensional diffusive medium. The light transmission through a sample is enhanced by efficiently coupling to open transmission channels using repeated digital optical phase conjugation. The spectral

  2. Writer identification using directional ink-trace width measurements

    NARCIS (Netherlands)

    Brink, A. A.; Smit, J.; Bulacu, M. L.; Schomaker, L. R. B.

    As suggested by modern paleography, the width of ink traces is a powerful source of information for off-line writer identification, particularly if combined with its direction. Such measurements can be computed using simple, fast and accurate methods based on pixel contours, the combination of which

  3. The effect of buffer zone width on biodiversity

    DEFF Research Database (Denmark)

    Navntoft, Søren; Sigsgaard, Lene; Kristensen, Kristian

    2012-01-01

    Field margin management for conservation purposes is a way to protect both functional biodiversity and biodiversity per se without considerable economical loss as field margins are less productive. However, the effect of width of the buffer zone on achievable biodiversity gains has received little...

  4. Analysis of Doppler effect with JAERI-Fast set

    International Nuclear Information System (INIS)

    Takano, Hideki; Matsui, Yasushi.

    1977-07-01

    Temperature dependence of group cross sections in the JAERI-Fast set versions I, IR, II and IIR has been tested from the analysis of Doppler experiments performed with two different methods. One is Doppler reactivity measurement for the whole core of SEFOR assembly, and the other sample Doppler reactivity measurement for natural UO 2 in FCA assemblies V-1, V-2, VI-1 and VI-2, ZPR-6-7, ZPR-3-47, and ZPPR-2 and 3. Doppler effects were calculated with one- and two-dimensional diffusion 1-st order perturbation code DOPP2D. The results calculated with the JAERI-Fast set versions II and IIR are in good agreement with the experimental ones. In these calculation, resonance heterogeneity effect, stainless-stell buffer effect and plate heterogeneity effect are considered, and these effects contribute significantly to Doppler effect. (auth.)

  5. Influence of MLC leaf width on biologically adapted IMRT plans

    Energy Technology Data Exchange (ETDEWEB)

    Roedal, Jan; Soevik, Aaste; Malinen, Eirik (Dept. of Medical Physics, The Norwegian Radium Hospital, Oslo Univ. Hospital, Oslo (Norway)), E-mail: jan.rodal@radiumhospitalet.no

    2010-10-15

    Introduction. High resolution beam delivery may be required for optimal biology-guided adaptive therapy. In this work, we have studied the influence of multi leaf collimator (MLC) leaf widths on the treatment outcome following adapted IMRT of a hypoxic tumour. Material and methods. Dynamic contrast enhanced MR images of a dog with a spontaneous tumour in the nasal region were used to create a tentative hypoxia map following a previously published procedure. The hypoxia map was used as a basis for generating compartmental gross tumour volumes, which were utilised as planning structures in biologically adapted IMRT. Three different MLCs were employed in inverse treatment planning, with leaf widths of 2.5 mm, 5 mm and 10 mm. The number of treatment beams and the degree of step-and-shoot beam modulation were varied. By optimising the tumour control probability (TCP) function, optimal compartmental doses were derived and used as target doses in the inverse planning. Resulting IMRT dose distributions and dose volume histograms (DVHs) were exported and analysed, giving estimates of TCP and compartmental equivalent uniform doses (EUDs). The impact of patient setup accuracy was simulated. Results. The MLC with the smallest leaf width (2.5 mm) consistently gave the highest TCPs and compartmental EUDs, assuming no setup error. The difference between this MLC and the 5 mm MLC was rather small, while the MLC with 10 mm leaf width gave considerably lower TCPs. When including random and systematic setup errors, errors larger than 5 mm gave only small differences between the MLC types. For setup errors larger than 7 mm no differences were found between non-uniform and uniform dose distributions. Conclusions. Biologically adapted radiotherapy may require MLCs with leaf widths smaller than 10 mm. However, for a high probability of cure it is crucial that accurate patient setup is ensured.

  6. Modeling of dislocation channel width evolution in irradiated metals

    Science.gov (United States)

    Doyle, Peter J.; Benensky, Kelsa M.; Zinkle, Steven J.

    2018-02-01

    Defect-free dislocation channel formation has been reported to promote plastic instability during tensile testing via localized plastic flow, leading to a distinct loss of ductility and strain hardening in many low-temperature irradiated materials. In order to study the underlying mechanisms governing dislocation channel width and formation, the channel formation process is modeled via a simple stochastic dislocation-jog process dependent upon grain size, defect cluster density, and defect size. Dislocations traverse a field of defect clusters and jog stochastically upon defect interaction, forming channels of low defect-density. Based upon prior molecular dynamics (MD) simulations and in-situ experimental transmission electron microscopy (TEM) observations, each dislocation encounter with a dislocation loop or stacking fault tetrahedron (SFT) is assumed to cause complete absorption of the defect cluster, prompting the dislocation to jog up or down by a distance equal to half the defect cluster diameter. Channels are predicted to form rapidly and are comparable to reported TEM measurements for many materials. Predicted channel widths are found to be most strongly dependent on mean defect size and correlated well with a power law dependence on defect diameter and density, and distance from the dislocation source. Due to the dependence of modeled channel width on defect diameter and density, maximum channel width is predicted to slowly increase as accumulated dose increases. The relatively weak predicted dependence of channel formation width with distance, in accordance with a diffusion analogy, implies that after only a few microns from the source, most channels observed via TEM analyses may not appear to vary with distance because of limitations in the field-of-view to a few microns. Further, examinations of the effect of the so-called "source-broadening" mechanism of channel formation showed that its effect is simply to add a minimum thickness to the channel

  7. Avaliação dos tumores hepáticos ao Doppler Doppler evaluation of liver tumors

    Directory of Open Access Journals (Sweden)

    Márcio Martins Machado

    2004-10-01

    Full Text Available Os avanços recentes na ultra-sonografia têm ampliado a possibilidade de detecção de tumores hepáticos. Isto tem auxiliado na perspectiva de melhora do prognóstico destes pacientes, à medida que novas técnicas terapêuticas têm surgido. Neste artigo os autores relatam achados ao Doppler que podem auxiliar na identificação e caracterização dos tumores hepáticos, avaliando dados do Doppler colorido, pulsado e do Doppler de amplitude ("power Doppler". Fazem, também, referência a novas modalidades de imagem, como o uso da harmônica.Recent advances in ultrasound have optimized the detection of liver tumors and helped to improve the prognosis of patients with this condition as newly developed and improved therapeutic modalities have been established. The authors review important Doppler findings which may help in the identification and characterization of some hepatic tumors through the evaluation of color Doppler, pulsed Doppler and power Doppler features. New imaging methods such as the use of harmonics imaging are also reviewed.

  8. Color Doppler US of superficial adenopathies; Il color Doppler nelle adenopatie superficiali

    Energy Technology Data Exchange (ETDEWEB)

    Giovagnorio, F. [Rome Univ. (Italy). 1. Cattedra di Radiologia

    1999-03-01

    Superficial lymph node are frequently involved in different diseases. Their location makes them suitable for effective assessment with high-resolution US and color Doppler has been recently suggested as a tool for increasing sensitivity in lymph node studies. Thus the author investigated the main vascular patterns detectable in abnormal superficial lymph nodes. [Italian] Numerosa malattie con natura differente coinvolgono i linfonodi superficiali: la localizzazione ne consente l'esplorazione con ecografia con alta risoluzione e lo studio mediante eco color Doppler e' stato proposto negli ultimi anni incontrando notevole sviluppo in tempi recenti. Scopo del lavoro e' illustrare il contributo personale nella definizione dei principali quadri riscontrabili nelle diverse adenopatie superficiali.

  9. Signal Processing Schemes for Doppler Global Velocimetry

    Science.gov (United States)

    Meyers, James F.; Lee, Joseph W.; Cavone, Angelo A.

    1991-01-01

    Two schemes for processing signals obtained from the Doppler global velocimeter are described. The analog approach is a simple, real time method for obtaining an RS-170 video signal containing the normalized intensity image. Pseudo colors are added using a monochromatic frame grabber producing a standard NTSC video signal that can be monitored and/or recorded. The digital approach is more complicated, but maintains the full resolution of the acquisition cameras with the capabilities to correct the signal image for pixel sensitivity variations and to remove of background light. Prototype circuits for each scheme are described and example results from the investigation of the vortical flow field above a 75-degree delta wing presented.

  10. Widefield laser doppler velocimeter: development and theory.

    Energy Technology Data Exchange (ETDEWEB)

    Hansche, Bruce David; Reu, Phillip L.; Massad, Jordan Elias

    2007-03-01

    The widefield laser Doppler velocimeter is a new measurement technique that significantly expands the functionality of a traditional scanning system. This new technique allows full-field velocity measurements without scanning, a drawback of traditional measurement techniques. This is particularly important for tests in which the sample is destroyed or the motion of the sample is non-repetitive. The goal of creating ''velocity movies'' was accomplished during the research, and this report describes the current functionality and operation of the system. The mathematical underpinnings and system setup are thoroughly described. Two prototype experiments are then presented to show the practical use of the current system. Details of the corresponding hardware used to collect the data and the associated software to analyze the data are presented.

  11. Doppler time-of-flight imaging

    KAUST Repository

    Heidrich, Wolfgang

    2017-02-16

    Systems and methods for imaging object velocity are provided. In an embodiment, at least one Time-of-Flight camera is used to capture a signal representative of an object in motion over an exposure time. Illumination and modulation frequency of the captured motion are coded within the exposure time. A change of illumination frequency is mapped to measured pixel intensities of the captured motion within the exposure time, and information about a Doppler shift in the illumination frequency is extracted to obtain a measurement of instantaneous per pixel velocity of the object in motion. The radial velocity information of the object in motion can be simultaneously captured for each pixel captured within the exposure time. In one or more aspects, the illumination frequency can be coded orthogonal to the modulation frequency of the captured motion. The change of illumination frequency can correspond to radial object velocity.

  12. Ultrasonic intrusion sensor using the Doppler effect; Choonpa Doppler hoshiki shinnyu sensor

    Energy Technology Data Exchange (ETDEWEB)

    Kani, H.; Iwasaki, N.; Goto, M. [Nippon Soken, Inc., Tokyo (Japan); Tsuzuki, T.; Nakamura, T. [Denso Corp., Aichi (Japan)

    1997-10-01

    For vehicle anti-theft alarm systems which cope with vehicle and car component theft, EU initiated vehicle security regulations from Jan 1997. Also, the insurance industry has instituted the insurance certification of vehicle anti-theft alarm systems. We have developed an ultrasonic intrusion sensor using the doppler effect for vehicle anti-theft alarm systems specifically for these EU regulations and insurance certification. 2 refs., 7 figs., 1 tab.

  13. Bone mineral density and mandibular residual ridge resorption.

    Science.gov (United States)

    Springe, Baiba; Slaidina, Anda; Soboleva, Una; Lejnieks, Aivars

    2014-01-01

    This prospective, cross-sectional study evaluated the relationship between bone mineral density (BMD) and the width and height parameters of the mandibular residual ridge. BMD was determined in the lumbar spine and femoral necks by dual energy x-ray absorptiometry (DXA) in 45 edentulous, postmenopausal women (mean age, 72.08 ± 8.53 years) who had used conventional complete dentures for at least 3 years. Measurements of the mandibular residual ridge were performed using cone beam computed tomography (CBCT). Height and width measurements were performed in the midline and adjacent to the mental foramina. Data were analyzed with descriptive and analytic statistics. The relationship between BMD and mandibular height and width measurements was assessed using analysis of variance as well as linear and multivariate regression analyses. Eight patients were excluded from the study because they did not complete both of the required imaging analyses (DXA and/or CBCT). There was no statistically significant relationship between BMD and mandibular bone height measurements in the midline and both regions of the mental foramina, and no statistically significant relationship existed between BMD and mandibular bone width measurements in the midline and both of the mental foramina regions. Postmenopausal women with reduced general BMD do not appear to have a reduction in the size of the mandibular residual ridge.

  14. Laser Doppler flowmetry in endodontics: a review.

    Science.gov (United States)

    Jafarzadeh, H

    2009-06-01

    Vascular supply is the most accurate marker of pulp vitality. Tests for assessing vascular supply that rely on the passage of light through a tooth have been considered as possible methods for detecting pulp vitality. Laser Doppler flowmetry (LDF), which is a noninvasive, objective, painless, semi-quantitative method, has been shown to be reliable for measuring pulpal blood flow. The relevant literature on LDF in the context of endodontics up to March 2008 was reviewed using PubMed and MEDLINE database searches. This search identified papers published between June 1983 and March 2008. Laser light is transmitted to the pulp by means of a fibre optic probe. Scattered light from moving red blood cells will be frequency-shifted whilst that from the static tissue remains unshifted. The reflected light, composed of Doppler-shifted and unshifted light, is returned by afferent fibres and a signal is produced. This technique has been successfully employed for estimating pulpal vitality in adults and children, differential diagnosis of apical radiolucencies (on the basis of pulp vitality), examining the reactions to pharmacological agents or electrical and thermal stimulation, and monitoring of pulpal responses to orthodontic procedures and traumatic injuries. Assessments may be highly susceptible to environmental and technique-related factors. Nonpulpal signals, principally from periodontal blood flow, may contaminate the signal. Because this test produces no noxious stimuli, apprehensive or distressed patients accept it more readily than current methods of pulp vitality assessment. A review of the literature and a discussion of the application of this system in endodontics are presented.

  15. Endoscopic laser Doppler flowmetry in evaluation of human gastric blood flow

    International Nuclear Information System (INIS)

    Lunde, O.C.

    1988-01-01

    The aims of the present study were to evaluate laser Doppler flowmetry (LDF) for endoscopic mesasurement of gastric blood flow. The study gave the following results: LDF is a reliable method for continuous measurement of gastrointestinal blood perfusion. This technique can be used endoscopically for measurement of gastric blood flow in conscious man. By means of endoscopic technique, relative blood flow changes can be measured in all parts of the stomach. The recorded blood flow values usually represent blood perfusion in all layers in the gastric wall. A slight contact pressure between the measuring probe and the mucosa is necessary to obtain stable recordings. To heavy pressure provokes reduction of flow values. Angulation of the probe and moderate air insufflation do not interfere with a constant flow level. Endoscopic measurements should be performed with a recording band-width of 4 kHz, since this frequency limit reduces the disturbing signals. Within the range of flow levels recorded in patients and healthy subjects, relative blood flow changes are measured with this band-width. Endoscopic LDF is safe and easy to handle. However, peristalsis and uneasy patients may sometime provoke disturbances which render blood flow measurements impossible. Endoscopic LDF is suitable for clinical studies such as investigation of the effect of drugs on gastric blood flow and examination of local blood flow in patients with gastric diseases

  16. Endoscopic laser Doppler flowmetry in evaluation of human gastric blood flow

    Energy Technology Data Exchange (ETDEWEB)

    Lunde, O.C. (Aker Sykehus, Oslo (Norway))

    1988-12-01

    The aims of the present study were to evaluate laser Doppler flowmetry (LDF) for endoscopic mesasurement of gastric blood flow. The study gave the following results: LDF is a reliable method for continuous measurement of gastrointestinal blood perfusion. This technique can be used endoscopically for measurement of gastric blood flow in conscious man. By means of endoscopic technique, relative blood flow changes can be measured in all parts of the stomach. The recorded blood flow values usually represent blood perfusion in all layers in the gastric wall. A slight contact pressure between the measuring probe and the mucosa is necessary to obtain stable recordings. To heavy pressure provokes reduction of flow values. Angulation of the probe and moderate air insufflation do not interfere with a constant flow level. Endoscopic measurements should be performed with a recording band-width of 4 kHz, since this frequency limit reduces the disturbing signals. Within the range of flow levels recorded in patients and healthy subjects, relative blood flow changes are measured with this band-width. Endoscopic LDF is safe and easy to handle. However, peristalsis and uneasy patients may sometime provoke disturbances which render blood flow measurements impossible. Endoscopic LDF is suitable for clinical studies such as investigation of the effect of drugs on gastric blood flow and examination of local blood flow in patients with gastric diseases. 64 refs.

  17. Role of colour doppler sonography in adnexal masses

    Directory of Open Access Journals (Sweden)

    Shazia Ashraf Khan, Aamina Banoo

    2014-04-01

    Full Text Available Objective: To evaluate the role of colour Doppler sonography in differentiating between benign and malignant adnexal masses. Materials & Methods: One hundred women diagnosed with adnexal masses underwent colour Doppler sonography. Resistance index (RI and Pulsatility index (PI were calculated in each case and lowest RI and PI obtained at any point in the mass were considered for analysis. Masses which were completely a vascular were considered as benign. Histopathological diagnosis was obtained in each case. Sensitivity, specificity, positive predictive value, negative predictive value and accuracy of colour Doppler were calculated. Results: Mean RI and Mean PI were significantly lower in malignant masses (0.34 & 0.95 respectively as compared to benign masses (0.72 & 1.97 respectively. Out of 81 benign cases, Doppler could correctly diagnose 78 cases as benign, but labelled 3 cases as malignant which were actually benign. Out of 19 malignant cases, 16 cases were correctly diagnosed, whereas 3 cases were missed by Doppler. Our study showed a sensitivity of 84.2%, specificity of 96.3%, positive predictive value of 84.2%, negative predictive value of 96.3% and accuracy of 94% for colour Doppler. Conclusion: Colour Doppler sonography is helpful in differentiating benign from malignant adnexal masses.

  18. Use of Doppler ultrasound for non-invasive urodynamic diagnosis

    Directory of Open Access Journals (Sweden)

    Hideo Ozawa

    2009-01-01

    Full Text Available Objectives: A totally non-invasive transperineal urodynamic technique using Doppler ultrasonography has been developed. Methods: Since normal urine does not have blood cells, urine was thought not to produce the Doppler effects. However, basic studies confirmed that the decrease of pressure at high velocity (Bernouilli effect caused dissolved gas to form microbubbles, which are detected by Doppler ultrasonography. Subjects sat and the probe was advanced via remote control to achieve gentle contact with the perineal skin. The digital uroflow data signals and the color Doppler ultrasound video images were processed on a personal computer. The flow-velocity curves from two sites; the distal prostatic urethra just above the external sphincter (V1 and the sphincteric urethra (V2 were plotted against time. The parameters of both the pressure-flow studies and the Doppler ultrasound urodynamic studies were compared in men who had various degrees of obstruction. Results: Functional cross-sectional area at prostatic urethra (A1, calculated by Q max /V1, was lower in the group of bladder outlet obstruction (BOO vs. control group. Velocity ratio (VR, which was calculated by V1/V2, was the parameter having the best correlation with BOO index, though A1 had a similar correlation. This method is viable to diagnose the degree of BOO. Conclusions: The development of non-invasive Doppler ultrasound videourodynamics (Doppler UDS will dramatically expand the information on voiding function.

  19. Wind turbine wake characterization using long-range Doppler lidar

    Science.gov (United States)

    Aitken, M.; Lundquist, J. K.; Hestmark, K.; Banta, R. M.; Pichugina, Y.; Brewer, A.

    2012-12-01

    Wind turbines extract energy from the freestream flow, resulting in a waked region behind the rotor which is characterized by reduced wind speed and increased turbulence. The velocity deficit in the wake diminishes with distance, as faster-moving air outside is gradually entrained. In a concentrated group of turbines, then, downwind machines experience very different inflow conditions compared to those in the front row. As utility-scale turbines rarely exist in isolation, detailed knowledge of the mean flow and turbulence structure inside wakes is needed to correctly model both power production and turbine loading at modern wind farms. To this end, the Turbine Wake and Inflow Characterization Study (TWICS) was conducted in the spring of 2011 to determine the reduction in wind speeds downstream from a multi-MW turbine located at the National Renewable Energy Laboratory's National Wind Technology Center (NWTC) near Boulder, Colorado. Full-scale measurements of wake dynamics are hardly practical or even possible with conventional sensors, such as cup anemometers mounted on meteorological (met) masts. Accordingly, the High Resolution Doppler Lidar (HRDL) developed by the National Oceanic and Atmospheric Administration's Earth System Research Laboratory was employed to investigate the formation and propagation of wakes under varying levels of ambient wind speed, shear, atmospheric stability, and turbulence. HRDL remotely senses line-of-sight wind velocities and has been used in several previous studies of boundary layer aerodynamics. With a fully steerable beam and a maximum range up to about 5 km, depending on atmospheric conditions, HRDL performed a comprehensive survey of the wind flow in front of and behind the turbine to study the shape, meandering, and attenuation of wakes. Due in large part to limited experimental data availability, wind farm wake modeling is still subject to an unacceptable amount of uncertainty, particularly in complex terrain. Here, analytical

  20. Simple discretization method for autoionization widths. III. Molecules

    International Nuclear Information System (INIS)

    Macas, A.; Martn, F.; Riera, A.; Yanez, M.

    1987-01-01

    We apply a new method to calculate widths of two-electron Feshbach resonances, which was described in detail and applied to atomic systems in preceding articles (this issue), to molecular and quasimolecular autoionizing states. For simplicity in the programming effort, we restrict our calculations to the small-R region where one-centered expansions are sufficiently accurate to describe the wave functions. As test cases, positions and widths for the H 2 , He 2 /sup 2+/, HeH + , and LiHe/sup 3+/ resonances of lowest energy are computed for R<0.6 a.u. The advantage of using block-diagonalization techniques to define diabatic resonant states instead of generalizing the Feshbach formalism is pointed out

  1. A Direct Measurement of the $W$ Decay Width

    Energy Technology Data Exchange (ETDEWEB)

    Vine, Troy [Univ. of College, London (United Kingdom)

    2008-08-01

    A direct measurement of the W boson total decay width is presented in proton-antiproton collisions at √s = 1.96 TeV using data collected by the CDF II detector. The measurement is made by fitting a simulated signal to the tail of the transverse mass distribution in the electron and muon decay channels. An integrated luminosity of 350 pb-1 is used, collected between February 2002 and August 2004. Combining the results from the separate decay channels gives the decay width as 2.038 ± 0.072 GeV in agreement with the theoretical prediction of 2.093 ± 0.002 GeV. A system is presented for the management of detector calibrations using a relational database schema. A description of the implementation and monitoring of a procedure to provide general users with a simple interface to the complete set of calibrations is also given.

  2. Determination of the width of the top quark.

    Science.gov (United States)

    Abazov, V M; Abbott, B; Abolins, M; Acharya, B S; Adams, M; Adams, T; Alexeev, G D; Alkhazov, G; Alton, A; Alverson, G; Alves, G A; Ancu, L S; Aoki, M; Arnoud, Y; Arov, M; Askew, A; Åsman, B; Atramentov, O; Avila, C; BackusMayes, J; Badaud, F; Bagby, L; Baldin, B; Bandurin, D V; Banerjee, S; Barberis, E; Baringer, P; Barreto, J; Bartlett, J F; Bassler, U; Bazterra, V; Beale, S; Bean, A; Begalli, M; Begel, M; Belanger-Champagne, C; Bellantoni, L; Beri, S B; Bernardi, G; Bernhard, R; Bertram, I; Besançon, M; Beuselinck, R; Bezzubov, V A; Bhat, P C; Bhatnagar, V; Blazey, G; Blessing, S; Bloom, K; Boehnlein, A; Boline, D; Bolton, T A; Boos, E E; Borissov, G; Bose, T; Brandt, A; Brandt, O; Brock, R; Brooijmans, G; Bross, A; Brown, D; Brown, J; Bu, X B; Buchholz, D; Buehler, M; Buescher, V; Bunichev, V; Burdin, S; Burnett, T H; Buszello, C P; Calpas, B; Camacho-Pérez, E; Carrasco-Lizarraga, M A; Casey, B C K; Castilla-Valdez, H; Chakrabarti, S; Chakraborty, D; Chan, K M; Chandra, A; Chen, G; Chevalier-Théry, S; Cho, D K; Cho, S W; Choi, S; Choudhary, B; Christoudias, T; Cihangir, S; Claes, D; Clutter, J; Cooke, M; Cooper, W E; Corcoran, M; Couderc, F; Cousinou, M-C; Croc, A; Cutts, D; Ćwiok, M; Das, A; Davies, G; De, K; de Jong, S J; De la Cruz-Burelo, E; Déliot, F; Demarteau, M; Demina, R; Denisov, D; Denisov, S P; Desai, S; DeVaughan, K; Diehl, H T; Diesburg, M; Dominguez, A; Dorland, T; Dubey, A; Dudko, L V; Duggan, D; Duperrin, A; Dutt, S; Dyshkant, A; Eads, M; Edmunds, D; Ellison, J; Elvira, V D; Enari, Y; Eno, S; Evans, H; Evdokimov, A; Evdokimov, V N; Facini, G; Ferbel, T; Fiedler, F; Filthaut, F; Fisher, W; Fisk, H E; Fortner, M; Fox, H; Fuess, S; Gadfort, T; Garcia-Bellido, A; Gavrilov, V; Gay, P; Geist, W; Geng, W; Gerbaudo, D; Gerber, C E; Gershtein, Y; Ginther, G; Golovanov, G; Goussiou, A; Grannis, P D; Greder, S; Greenlee, H; Greenwood, Z D; Gregores, E M; Grenier, G; Gris, Ph; Grivaz, J-F; Grohsjean, A; Grünendahl, S; Grünewald, M W; Guo, F; Guo, J; Gutierrez, G; Gutierrez, P; Haas, A; Hagopian, S; Haley, J; Han, L; Harder, K; Harel, A; Hauptman, J M; Hays, J; Head, T; Hebbeker, T; Hedin, D; Hegab, H; Heinson, A P; Heintz, U; Hensel, C; Heredia-De la Cruz, I; Herner, K; Hesketh, G; Hildreth, M D; Hirosky, R; Hoang, T; Hobbs, J D; Hoeneisen, B; Hohlfeld, M; Hossain, S; Hubacek, Z; Huske, N; Hynek, V; Iashvili, I; Illingworth, R; Ito, A S; Jabeen, S; Jaffré, M; Jain, S; Jamin, D; Jesik, R; Johns, K; Johnson, M; Johnston, D; Jonckheere, A; Jonsson, P; Joshi, J; Juste, A; Kaadze, K; Kajfasz, E; Karmanov, D; Kasper, P A; Katsanos, I; Kehoe, R; Kermiche, S; Khalatyan, N; Khanov, A; Kharchilava, A; Kharzheev, Y N; Khatidze, D; Kirby, M H; Kohli, J M; Kozelov, A V; Kraus, J; Kumar, A; Kupco, A; Kurča, T; Kuzmin, V A; Kvita, J; Lammers, S; Landsberg, G; Lebrun, P; Lee, H S; Lee, S W; Lee, W M; Lellouch, J; Li, L; Li, Q Z; Lietti, S M; Lim, J K; Lincoln, D; Linnemann, J; Lipaev, V V; Lipton, R; Liu, Y; Liu, Z; Lobodenko, A; Lokajicek, M; Love, P; Lubatti, H J; Luna-Garcia, R; Lyon, A L; Maciel, A K A; Mackin, D; Madar, R; Magaña-Villalba, R; Malik, S; Malyshev, V L; Maravin, Y; Martínez-Ortega, J; McCarthy, R; McGivern, C L; Meijer, M M; Melnitchouk, A; Menezes, D; Mercadante, P G; Merkin, M; Meyer, A; Meyer, J; Mondal, N K; Muanza, G S; Mulhearn, M; Nagy, E; Naimuddin, M; Narain, M; Nayyar, R; Neal, H A; Negret, J P; Neustroev, P; Novaes, S F; Nunnemann, T; Obrant, G; Orduna, J; Osman, N; Osta, J; Otero y Garzón, G J; Owen, M; Padilla, M; Pangilinan, M; Parashar, N; Parihar, V; Park, S K; Parsons, J; Partridge, R; Parua, N; Patwa, A; Penning, B; Perfilov, M; Peters, K; Peters, Y; Petrillo, G; Pétroff, P; Piegaia, R; Piper, J; Pleier, M-A; Podesta-Lerma, P L M; Podstavkov, V M; Pol, M-E; Polozov, P; Popov, A V; Prewitt, M; Price, D; Protopopescu, S; Qian, J; Quadt, A; Quinn, B; Rangel, M S; Ranjan, K; Ratoff, P N; Razumov, I; Renkel, P; Rich, P; Rijssenbeek, M; Ripp-Baudot, I; Rizatdinova, F; Rominsky, M; Royon, C; Rubinov, P; Ruchti, R; Safronov, G; Sajot, G; Sánchez-Hernández, A; Sanders, M P; Sanghi, B; Santos, A S; Savage, G; Sawyer, L; Scanlon, T; Schamberger, R D; Scheglov, Y; Schellman, H; Schliephake, T; Schlobohm, S; Schwanenberger, C; Schwienhorst, R; Sekaric, J; Severini, H; Shabalina, E; Shary, V; Shchukin, A A; Shivpuri, R K; Simak, V; Sirotenko, V; Skubic, P; Slattery, P; Smirnov, D; Smith, K J; Snow, G R; Snow, J; Snyder, S; Söldner-Rembold, S; Sonnenschein, L; Sopczak, A; Sosebee, M; Soustruznik, K; Spurlock, B; Stark, J; Stolin, V; Stoyanova, D A; Strauss, E; Strauss, M; Strom, D; Stutte, L; Svoisky, P; Takahashi, M; Tanasijczuk, A; Taylor, W; Titov, M; Tokmenin, V V; Tsybychev, D; Tuchming, B; Tully, C; Tuts, P M; Uvarov, L; Uvarov, S; Uzunyan, S; Van Kooten, R; van Leeuwen, W M; Varelas, N; Varnes, E W; Vasilyev, I A; Verdier, P; Vertogradov, L S

    2011-01-14

    We extract the total width of the top quark, Γ(t), from the partial decay width Γ(t → Wb) measured using the t-channel cross section for single top-quark production and from the branching fraction B(t → Wb) measured in tt events using up to 2.3  fb(-1) of integrated luminosity collected by the D0 Collaboration at the Tevatron pp Collider. The result is Γ(t) = 1.99(-0.55)(+0.69)  GeV, which translates to a top-quark lifetime of τ(t) = (3.3(-0.9)(+1.3)) × 10(-25)   s. Assuming a high mass fourth generation b' quark and unitarity of the four-generation quark-mixing matrix, we set the first upper limit on |V(tb')| < 0.63 at 95% C.L.

  3. Statistical analysis of P-wave neutron reduced widths

    International Nuclear Information System (INIS)

    Joshi, G.C.; Agrawal, H.M.

    2000-01-01

    The fluctuations of the p-wave neutron reduced widths for fifty one nuclei have been analyzed with emphasis on recent measurements by a statistical procedure which is based on the method of maximum likelihood. It is shown that the p-wave neutron reduced widths of even-even nuclei fallow single channel Porter Thomas distribution (χ 2 -distribution with degree of freedom ν=1) for most of the cases where there are no intermediate structure. It is emphasized that the distribution in nuclei other than even-even may differ from a χ 2 -distribution with one degree of freedom. Possible explanation and significance of this deviation from ν=1 is given. (author)

  4. The SOL width and the MHD interchange instability in tokamaks

    Energy Technology Data Exchange (ETDEWEB)

    Kerner, W. [Commission of the European Communities, Abingdon (United Kingdom). JET Joint Undertaking; Pogutse, O. [Kurchatov institute, Moscow (Russian Federation)

    1994-07-01

    Instabilities in the SOL plasma can strongly influence the SOL plasma behaviour and in particular the SOL width. The SOL stability analysis shows that there exists a critical ratio of the thermal energy and the magnetic energy. If the SOL beta is greater than this critical value, the magnetic field cannot prevent the plasma displacement and a strong MHD instability in the SOL occurs. In the opposite case only slower resistive instabilities can develop. A theoretical investigation of the SOL plasma stability is presented for JET single-null and double-null divertor configurations. The dependence of the stability threshold on the SOL beta and on the sheath resistance is established. Applying a simple mixing length argument gives the scaling of the SOL width. 5 refs., 2 figs.

  5. Optical coherence techniques for plasma doppler spectroscopy

    International Nuclear Information System (INIS)

    Howard, J.; Michael, C.; Glass, F.; Cheetham, A.D.

    2000-01-01

    A new electro-optically Modulated Optical Solid-State (MOSS) interferometer has been constructed for measurement of the low order spectral moments of line emission from optically thin radiant media. The instrument, which is based on the principle of the Fourier transform spectrometer, has high etendue and is rugged, compact and inexpensive. By employing electro-optical path-length modulation techniques, the spectral information is transferred to the temporal frequency domain and can be obtained using a single photodetector. Specifically, the zeroth moment (brightness) is given by the average signal level, the first moment (shift) by the modulation phase and the second moment (line width) by the modulation amplitude. (author)

  6. Numerical Solution of the Modified Equal Width Wave Equation

    Directory of Open Access Journals (Sweden)

    Seydi Battal Gazi Karakoç

    2012-01-01

    Full Text Available Numerical solution of the modified equal width wave equation is obtained by using lumped Galerkin method based on cubic B-spline finite element method. Solitary wave motion and interaction of two solitary waves are studied using the proposed method. Accuracy of the proposed method is discussed by computing the numerical conserved laws 2 and ∞ error norms. The numerical results are found in good agreement with exact solution. A linear stability analysis of the scheme is also investigated.

  7. Pulse-Width-Modulating Driver for Brushless dc Motor

    Science.gov (United States)

    Salomon, Phil M.

    1991-01-01

    High-current pulse-width-modulating driver for brushless dc motor features optical coupling of timing signals from low-current control circuitry to high-current motor-driving circuitry. Provides high electrical isolation of motor-power supply, helping to prevent fast, high-current motor-driving pulses from being coupled through power supplies into control circuitry, where they interfere with low-current control signals.

  8. Synchronization Technique for Random Switching Frequency Pulse-Width Modulation

    OpenAIRE

    Apinan Aurasopon; Worawat Sa-ngiavibool

    2008-01-01

    This paper proposes a synchronized random switching frequency pulse width modulation (SRSFPWM). In this technique, the clock signal is used to control the random noise frequency which is produced by the feedback voltage of a hysteresis circuit. These make the triangular carrier frequency equaling to the random noise frequency in each switching period with the symmetrical positive and negative slopes of triangular carrier. Therefore, there is no error voltage in PWM signal. The PSpice simulate...

  9. Penning ionization widths by Fano-algebraic diagrammatic construction method

    Science.gov (United States)

    Yun, Renjie; Narevicius, Edvardas; Averbukh, Vitali

    2018-03-01

    We present an ab initio theory and computational method for Penning ionization widths. Our method is based on the Fano theory of resonances, algebraic diagrammatic construction (ADC) scheme for many-electron systems, and Stieltjes imaging procedure. It includes an extension of the Fano-ADC scheme [V. Averbukh and L. S. Cederbaum, J. Chem. Phys. 123, 204107 (2005)] to triplet excited states. Penning ionization widths of various He*-H2 states are calculated as a function of the distance R between He* and H2. We analyze the asymptotic (large-R) dependences of the Penning widths in the region where the well-established electron transfer mechanism of the decay is suppressed by the multipole- and/or spin-forbidden energy transfer. The R-12 and R-8 power laws are derived for the asymptotes of the Penning widths of the singlet and triplet excited states of He*(1s2s1,3S), respectively. We show that the electron transfer mechanism dominates Penning ionization of He*(1s2s 3S)-H2 up until the He*-H2 separation is large enough for the radiative decay of He* to become the dominant channel. The same mechanism also dominates the ionization of He*(1s2s 1S)-H2 when R < 5 Å. We estimate that the regime of energy transfer in the He*-H2 Penning ionization cannot be reached by approaching zero collisional temperature. However, the multipole-forbidden energy transfer mechanism can become important for Penning ionization in doped helium droplets.

  10. Pole mass, width, and propagators of unstable fermions

    International Nuclear Information System (INIS)

    Kniehl, B.A.; Sirlin, A.

    2008-01-01

    The concepts of pole mass and width are extended to unstable fermions in the general framework of parity-nonconserving gauge theories, such as the Standard Model. In contrast with the conventional on-shell definitions, these concepts are gauge independent and avoid severe unphysical singularities, properties of great importance since most fundamental fermions in nature are unstable particles. General expressions for the unrenormalized and renormalized dressed propagators of unstable fermions and their field-renormalization constants are presented. (orig.)

  11. Pulsed Doppler echocardiographic analysis of mitral regurgitation after myocardial infarction.

    Science.gov (United States)

    Loperfido, F; Biasucci, L M; Pennestri, F; Laurenzi, F; Gimigliano, F; Vigna, C; Rossi, E; Favuzzi, A; Santarelli, P; Manzoli, U

    1986-10-01

    In 72 patients with previous myocardial infarction (MI), mitral regurgitation (MR) was assessed by pulsed-wave Doppler echocardiography and compared with physical and 2-dimensional echocardiographic findings. MR was found by Doppler in 29 of 42 patients (62%) with anterior MI, 11 of 30 (37%) with inferior MI (p less than 0.01) and in none of 20 normal control subjects. MR was more frequent in patients who underwent Doppler study 3 months after MI than in those who underwent Doppler at discharge (anterior MI = 83% vs 50%, p less than 0.01; inferior MI = 47% vs 27%, p = not significant). Of 15 patients who underwent Doppler studies both times, 3 (all with anterior MI) had MR only on the second study. Of the patients with Doppler MR, 12 of 27 (44%) with a left ventricular (LV) ejection fraction (EF) greater than 30% and 1 of 13 (8%) with an EF of 30% or less (p less than 0.01) had an MR systolic murmur. Mitral prolapse or eversion and papillary muscle fibrosis were infrequent in MI patients, whether or not Doppler MR was present. The degree of Doppler MR correlated with EF (r = -0.61), LV systolic volume (r = 0.47), and systolic and diastolic mitral anulus circumference (r = 0.52 and 0.51, respectively). Doppler MR was present in 24 of 28 patients (86%) with an EF of 40% or less and in 16 of 44 (36%) with EF more than 40% (p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

  12. Predicting Factors for Successful Maturation of Autogenous Haemodialysis Fistulas After Salvage Percutaneous Transluminal Angioplasty in Diabetic Nephropathy: A Study on Follow-Up Doppler Ultrasonography

    International Nuclear Information System (INIS)

    Jeon, Eui-Yong; Cho, Young Kwon; Cho, Sung Bum; Yoon, Dae Young; Suh, Seong O

    2016-01-01

    Maturation failure of autogenous arteriovenous fistula (aAVF) has been increasing after surgical procedures and the salvage percutaneous transluminal angioplasty (sPTA) for immature aAVF has been identified as an effective treatment modality. The aim of this study was to identify factors predicting successful aAVF maturation and to determine positive technical aspects of sPTA. We retrospectively reviewed medical records and radiological images of 59 patients who had undergone sPTA for non-maturing aAVFs. We analysed images from pre-surgical mapping Doppler ultrasonography, angiography, and angioplasty and follow-up Doppler ultrasonography performed within two weeks after sPTA. We assessed the following factors, for their ability to predict successful aAVF maturation: 1) patient factors (age; sex; co-morbidities; and aAVF age, side and type); 2) vessel factors (cephalic vein diameter and depth, presence of accessory veins, and pre- and postoperative radial artery disease); 3) lesion factors (stenosis number, location and severity); and 4) technical factors (presence of residual stenosis and anatomic success ratio (ASR) on follow-up Doppler ultrasonography). The technical and clinical success rates were both 94.9% (56/59); the mean ASR was 0.84. An ASR of ≥ 0.7 and no significant residual stenosis (< 30%) (both P < 0.001) on two-week follow-up Doppler ultrasonography predicted successful aAVF maturation. For more precise prediction of successful aAVF maturation after sPTA, short-term follow-up Doppler ultrasonography (< 2 weeks) was useful. If the ASR was < 0.7 or if residual stenosis was ≥ 30%, immediate repeat sPTA is recommended

  13. Balance (perceived and actual) and preferred stance width during pregnancy.

    Science.gov (United States)

    Jang, John; Hsiao, Katherine T; Hsiao-Wecksler, Elizabeth T

    2008-05-01

    Pregnant women often remark that their balance degrades during pregnancy; however, it appears that no studies have documented the gravida's perception of her balance nor measured direction-specific changes in balance throughout pregnancy or after delivery. Thirty women, fifteen pregnant and fifteen non-pregnant controls, were tested monthly and through 6-month postpartum. For each session, perceived degradation in sense of balance, laboratory-based balance measures, stance width, and the number of falls since the previous session were recorded. Laboratory-based balance measures, quantified by direction-specific measures of postural sway, were computed from ten 30s quiet-standing trials on a stationary force platform. Repeated-measures analysis of variance, paired t-tests, and Pearson correlations were use to examine group and time effects. For the pregnant group, perceived balance degradation and stance width were highly correlated (r = 0.94). Both increased during pregnancy (P r > 0.72) and also decreased significantly between the third trimester and postpartum (P pregnancy, but increased after delivery. Contrary to recent work suggesting fall rates of 25%, only 13% of our subjects (n = 2) fell during pregnancy. Perceived degradation in balance during pregnancy was strongly related to increasing postural sway instability in the anterior-posterior direction. Lateral stability was maintained during pregnancy and likely accomplished by increasing stance width.

  14. Predictors of the peak width for networks with exponential links

    Science.gov (United States)

    Troutman, B.M.; Karlinger, M.R.

    1989-01-01

    We investigate optimal predictors of the peak (S) and distance to peak (T) of the width function of drainage networks under the assumption that the networks are topologically random with independent and exponentially distributed link lengths. Analytical results are derived using the fact that, under these assumptions, the width function is a homogeneous Markov birth-death process. In particular, exact expressions are derived for the asymptotic conditional expectations of S and T given network magnitude N and given mainstream length H. In addition, a simulation study is performed to examine various predictors of S and T, including N, H, and basin morphometric properties; non-asymptotic conditional expectations and variances are estimated. The best single predictor of S is N, of T is H, and of the scaled peak (S divided by the area under the width function) is H. Finally, expressions tested on a set of drainage basins from the state of Wyoming perform reasonably well in predicting S and T despite probable violations of the original assumptions. ?? 1989 Springer-Verlag.

  15. Measurement of the mass and width of the W boson

    CERN Document Server

    Abbiendi, G.; Akesson, P.F.; Alexander, G.; Anagnostou, G.; Anderson, K.J.; Asai, S.; Axen, D.; Bailey, I.; Barberio, E.; Barillari, T.; Barlow, R.J.; Batley, R.J.; Bechtle, P.; Behnke, T.; Bell, Kenneth Watson; Bell, P.J.; Bella, G.; Bellerive, A.; Benelli, G.; Bethke, S.; Biebel, O.; Boeriu, O.; Bock, P.; Boutemeur, M.; Braibant, S.; Brown, Robert M.; Burckhart, H.J.; Campana, S.; Capiluppi, P.; Carnegie, R.K.; Carter, A.A.; Carter, J.R.; Chang, C.Y.; Charlton, D.G.; Ciocca, C.; Csilling, A.; Cuffiani, M.; Dado, S.; De Roeck, A.; De Wolf, E.A.; Desch, K.; Dienes, B.; Dubbert, J.; Duchovni, E.; Duckeck, G.; Duerdoth, I.P.; Etzion, E.; Fabbri, F.; Ferrari, P.; Fiedler, F.; Fleck, I.; Ford, M.; Frey, A.; Gagnon, P.; Gary, John William; Geich-Gimbel, C.; Giacomelli, G.; Giacomelli, P.; Giunta, Marina; Goldberg, J.; Gross, E.; Grunhaus, J.; Gruwe, M.; Gunther, P.O.; Gupta, A.; Hajdu, C.; Hamann, M.; Hanson, G.G.; Harel, A.; Hauschild, M.; Hawkes, C.M.; Hawkings, R.; Hemingway, R.J.; Herten, G.; Heuer, R.D.; Hill, J.C.; Horvath, D.; Igo-Kemenes, P.; Ishii, K.; Jeremie, H.; Jovanovic, P.; Junk, T.R.; Kanzaki, J.; Karlen, D.; Kawagoe, K.; Kawamoto, T.; Keeler, R.K.; Kellogg, R.G.; Kennedy, B.W.; Kluth, S.; Kobayashi, T.; Kobel, M.; Komamiya, S.; Kramer, T.; Krasznahorkay, A.; Krieger, P.; von Krogh, J.; Kuhl, T.; Kupper, M.; Lafferty, G.D.; Landsman, H.; Lanske, D.; Lellouch, D.; Letts, J.; Levinson, L.; Lillich, J.; Lloyd, S.L.; Loebinger, F.K.; Lu, J.; Ludwig, A.; Ludwig, J.; Mader, W.; Marcellini, S.; Martin, A.J.; Mashimo, T.; Mattig, Peter; McKenna, J.; McPherson, R.A.; Meijers, F.; Menges, W.; Merritt, F.S.; Mes, H.; Meyer, Niels T.; Michelini, A.; Mihara, S.; Mikenberg, G.; Miller, D.J.; Mohr, W.; Mori, T.; Mutter, A.; Nagai, K.; Nakamura, I.; Nanjo, H.; Neal, H.A.; Nisius, R.; O'Neale, S.W.; Oh, A.; Oreglia, M.J.; Orito, S.; Pahl, C.; Pasztor, G.; Pater, J.R.; Pilcher, J.E.; Pinfold, J.; Plane, David E.; Pooth, O.; Przybycien, M.; Quadt, A.; Rabbertz, K.; Rembser, C.; Renkel, P.; Roney, J.M.; Rossi, A.M.; Rozen, Y.; Runge, K.; Sachs, K.; Saeki, T.; Sarkisyan, E.K.G.; Schaile, A.D.; Schaile, O.; Scharff-Hansen, P.; Schieck, J.; Schorner-Sadenius, T.; Schroder, Matthias; Schumacher, M.; Seuster, R.; Shears, T.G.; Shen, B.C.; Sherwood, P.; Skuja, A.; Smith, A.M.; Sobie, R.; Soldner-Rembold, S.; Spano, F.; Stahl, A.; Strom, David M.; Strohmer, R.; Tarem, S.; Tasevsky, M.; Teuscher, R.; Thomson, M.A.; Torrence, E.; Toya, D.; Tran, P.; Trigger, I.; Trocsanyi, Z.; Tsur, E.; Turner-Watson, M.F.; Ueda, I.; Ujvari, B.; Vollmer, C.F.; Vannerem, P.; Vertesi, R.; Verzocchi, M.; Voss, H.; Vossebeld, J.; Ward, C.P.; Ward, D.R.; Watkins, P.M.; Watson, A.T.; Watson, N.K.; Wells, P.S.; Wengler, T.; Wermes, N.; Wilson, G.W.; Wilson, J.A.; Wolf, G.; Wyatt, T.R.; Yamashita, S.; Zer-Zion, D.; Zivkovic, Lidija

    2006-01-01

    The mass and width of the W boson are measured using e+e- -> W+W- events from the data sample collected by the OPAL experiment at LEP at centre-of-mass energies between 170 GeV and 209 GeV. The mass (mw) and width (gw) are determined using direct reconstruction of the kinematics of W+W- -> qqbarlv and W+W- -> qqbarqqbar events. When combined with previous OPAL measurements using W+W- -> lvlv events and the dependence on mw of the WW production cross-section at threshold, the results are determined to be mw = 80.415 +- 0.042 +- 0.030 +- 0.009 GeV gw = 1.996 +- 0.096 +- 0.102 +- 0.003 GeV where the first error is statistical, the second systematic and the third due to uncertainties in the value of the LEP beam energy. By measuring mw with several different jet algorithms in the qqbarqqbar channel, a limit is also obtained on possible final-state interactions due to colour reconnection effects in W+W- -> qqbarqqbar events. The consistency of the results for the W mass and width with those inferred from other ele...

  16. Stark widths regularities within spectral series of sodium isoelectronic sequence

    Science.gov (United States)

    Trklja, Nora; Tapalaga, Irinel; Dojčinović, Ivan P.; Purić, Jagoš

    2018-02-01

    Stark widths within spectral series of sodium isoelectronic sequence have been studied. This is a unique approach that includes both neutrals and ions. Two levels of problem are considered: if the required atomic parameters are known, Stark widths can be calculated by some of the known methods (in present paper modified semiempirical formula has been used), but if there is a lack of parameters, regularities enable determination of Stark broadening data. In the framework of regularity research, Stark broadening dependence on environmental conditions and certain atomic parameters has been investigated. The aim of this work is to give a simple model, with minimum of required parameters, which can be used for calculation of Stark broadening data for any chosen transitions within sodium like emitters. Obtained relations were used for predictions of Stark widths for transitions that have not been measured or calculated yet. This system enables fast data processing by using of proposed theoretical model and it provides quality control and verification of obtained results.

  17. Strip-tillage: A conservation alternative to full-width tillage systems

    Science.gov (United States)

    Wolkowski, Richard

    2015-04-01

    Historically no-till management has been a challenge for maize production in the Midwestern USA because crop residue slows the warming of the soil in the spring and can physically impair planting by plugging the planter. After trying no-till, producers often return to more aggressive tillage operations to address residue concerns; however these systems can cause soil erosion and can increase the cost of production. An alternative system known as strip-tillage has been suggested as a compromise between no-till and full-width tillage. This practice utilizes implements that loosen the soil and allow warming in the row area, yet maintain nearly as much residue as no-till. Strip-tillage is generally understood to be a single pass with a separate implement in the fall, although spring strip-tillage is possible if soil moisture and conditions permit. Strip-tillage can be accomplished in a shorter time, with lower energy and equipment inputs compared to full-width tillage. The first of two studies that examined the merits of strip-tillage was conducted the University of Wisconsin Lancaster Agricultural Research Station (42.84, -90.80). Natural runoff collectors were installed in a field having a silt loam soil with an 8% slope in fall chisel and fall strip-tillage system. The measured soil loss in a year that experienced substantial rainfall prior to canopy closure was 10.6 Mg ha-1 in chisel vs. 0.64 Mg ha-1 in strip-tillage. Soil loss was much less for both systems in the second year when early season rainfall was minimal. A second, ten year study was conducted at the University of Wisconsin Arlington Agricultural Research Station (43.30, -89.36) that compared fall strip-tillage with fall chisel/spring field cultivator and no-till systems in both a continuous maize and soybean-maize rotation. This work showed equal maize grain yield in maize after soybean when comparing chisel and strip-tillage. No-till yield was about 5 % lower. Yield in continuous maize was highest in

  18. Stratospheric temperature measurement with scanning Fabry-Perot interferometer for wind retrieval from mobile Rayleigh Doppler lidar.

    Science.gov (United States)

    Xia, Haiyun; Dou, Xiankang; Shangguan, Mingjia; Zhao, Ruocan; Sun, Dongsong; Wang, Chong; Qiu, Jiawei; Shu, Zhifeng; Xue, Xianghui; Han, Yuli; Han, Yan

    2014-09-08

    Temperature detection remains challenging in the low stratosphere, where the Rayleigh integration lidar is perturbed by aerosol contamination and ozone absorption while the rotational Raman lidar is suffered from its low scattering cross section. To correct the impacts of temperature on the Rayleigh Doppler lidar, a high spectral resolution lidar (HSRL) based on cavity scanning Fabry-Perot Interferometer (FPI) is developed. By considering the effect of the laser spectral width, Doppler broadening of the molecular backscatter, divergence of the light beam and mirror defects of the FPI, a well-behaved transmission function is proved to show the principle of HSRL in detail. Analysis of the statistical error of the HSRL is carried out in the data processing. A temperature lidar using both HSRL and Rayleigh integration techniques is incorporated into the Rayleigh Doppler wind lidar. Simultaneous wind and temperature detection is carried out based on the combined system at Delhi (37.371°N, 97.374°E; 2850 m above the sea level) in Qinghai province, China. Lower Stratosphere temperature has been measured using HSRL between 18 and 50 km with temporal resolution of 2000 seconds. The statistical error of the derived temperatures is between 0.2 and 9.2 K. The temperature profile retrieved from the HSRL and wind profile from the Rayleigh Doppler lidar show good agreement with the radiosonde data. Specifically, the max temperature deviation between the HSRL and radiosonde is 4.7 K from 18 km to 36 km, and it is 2.7 K between the HSRL and Rayleigh integration lidar from 27 km to 34 km.

  19. Interferometric millimeter wave and THz wave doppler radar

    Energy Technology Data Exchange (ETDEWEB)

    Liao, Shaolin; Gopalsami, Nachappa; Bakhtiari, Sasan; Raptis, Apostolos C.; Elmer, Thomas

    2015-08-11

    A mixerless high frequency interferometric Doppler radar system and methods has been invented, numerically validated and experimentally tested. A continuous wave source, phase modulator (e.g., a continuously oscillating reference mirror) and intensity detector are utilized. The intensity detector measures the intensity of the combined reflected Doppler signal and the modulated reference beam. Rigorous mathematics formulas have been developed to extract bot amplitude and phase from the measured intensity signal. Software in Matlab has been developed and used to extract such amplitude and phase information from the experimental data. Both amplitude and phase are calculated and the Doppler frequency signature of the object is determined.

  20. Spectroscopy at the solar limb. I. Average off-limb profiles and Doppler shifts of Ca II H

    Science.gov (United States)

    Beck, C. A. R.; Rezaei, R.

    2011-07-01

    Aims: We present constraints on the thermodynamical structure of the chromosphere from ground-based observations of the Ca ii H line profile near and off the solar limb. Methods: We obtained a slit-spectrograph data set of the Ca ii H line with a high signal-to-noise ratio in a field of view extending 20'' across the limb. We analyzed the spectra for the characteristic properties of average and individual off-limb spectra. We used various tracers of the Doppler shifts, such as the location of the absorption core, the ratio of the two emission peaks H2V and H2R, and intensity images at a fixed wavelength. Results: The average off-limb profiles show a smooth variation with increasing limb distance. The line width increases up to a height of about 2 Mm above the limb. The profile shape is fairly symmetric with nearly identical H2V and H2R intensities; at a height of 5 Mm, it changes into a single Gaussian without emission peaks. We find that all off-limb spectra show large Doppler shifts that fluctuate on the smallest resolved spatial scales. The variation is more prominent in cuts parallel to the solar limb than on those perpendicular to it. As far as individual structures can be unequivocally identified at our spatial resolution, we find a specific relation between intensity enhancements and Doppler shifts: elongated brightenings are often flanked all along their extension by velocities in opposite directions. Conclusions: The average off-limb spectra of Ca ii H present a good opportunity to test static chromospheric atmosphere models because they lack the photospheric contribution that is present in disk-center spectra. We suggest that the observed relation between intensity enhancements and Doppler shifts could be caused by waves propagating along the surfaces of flux tubes: an intrinsic twist of the flux tubes or a wave propagation inclined to the tube axis would cause a helical shape of the Doppler excursions, visible as opposite velocity at the sides of the

  1. Residual gas analysis

    International Nuclear Information System (INIS)

    Berecz, I.

    1982-01-01

    Determination of the residual gas composition in vacuum systems by a special mass spectrometric method was presented. The quadrupole mass spectrometer (QMS) and its application in thin film technology was discussed. Results, partial pressure versus time curves as well as the line spectra of the residual gases in case of the vaporization of a Ti-Pd-Au alloy were demonstrated together with the possible construction schemes of QMS residual gas analysers. (Sz.J.)

  2. Analysis Of The Effect Of Flow Channel Width On The Performance Of PEMFC

    Directory of Open Access Journals (Sweden)

    Elif Eker

    2013-08-01

    Full Text Available In this work, it was analysed the effect of different channel width on performance of PEM fuel cell. Current density were measured on the single cells of parallel flow fields that has 25 cm² active layer, using three different kinds of channel width. The cell width and the channel height remain constant.The results show that increasing the channel width while the cell width remains constant decreases the current density.

  3. CAMEX-4 MIPS 915 MHZ DOPPLER WIND PROFILER V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The University of Alabama in Huntsville (UAH) Mobile Integrated Profiling System (MIPS) is a mobile atmospheric profiling system. It includes a 915 MHz Doppler...

  4. Micro-Doppler Analysis of Rotating Target in SAR

    National Research Council Canada - National Science Library

    Thayaparan, T; Abrol, S; Qian, S

    2005-01-01

    .... The phase modulation may be seen as a time-dependent micro-Doppler (m-D) frequency. Due to their superior resolution potential, it is useful to analyze such signals with time-frequency analysis methods...

  5. Differentiation of midbrain cystic lesions by duplex Doppler US

    International Nuclear Information System (INIS)

    Horgan, J.G.; Taylor, K.J.W.; Sarwar, M.; Weltin, G.; Klier, L.

    1986-01-01

    The addition of Doppler technology to an ultrasound imaging system allows easy differentiation of vascular from nonvascular masses. In addition, the characteristic flow in different arteries, veins, and arteriovenous communications allows accurate diagnosis of vascular structures. Cystic lesions in the region of the midbrain are uncommon but not rare in neonates, and it is important to differentiate between quadrigeminal plate cysts and vein of Galen aneurysms. Six neonates with cystic midbrain structures lying above the tectum were studied over a 2-year period. All were examined with duplex Doppler imaging and followed up by CT and angiography, when indicated. In two of the six infants a highly vascular signal was demonstrated with high flow rates and low impedance. Subsequent CT and angiography revealed typical vein of Galen aneurysms. The remaining four infants had cystic lesions that were avascular on Doppler imaging and demonstrated no enhancement on CT. Duplex Doppler imaging is helpful in the initial investigation of patients with midbrain cystic lesions

  6. GRIP DOPPLER AEROSOL WIND LIDAR (DAWN) V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The Doppler Aerosol WiNd (DAWN), a pulsed lidar, operated aboard a NASA DC-8 aircraft during the Genesis and Rapid Intensification Processes (GRIP) field campaign....

  7. Apparatus and method for noninvasive particle detection using doppler spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Sinha, Dipen N.

    2016-05-31

    An apparatus and method for noninvasively detecting the presence of solid particulate matter suspended in a fluid flowing through a pipe or an oil and gas wellbore are described. Fluid flowing through a conduit containing the particulate solids is exposed to a fixed frequency (>1 MHz) of ultrasonic vibrations from a transducer attached to the outside of the pipe. The returning Doppler frequency shifted signal derived from the scattering of sound from the moving solid particles is detected by an adjacent transducer. The transmitted signal and the Doppler signal are combined to provide sensitive particulate detection. The magnitude of the signal and the Doppler frequency shift are used to determine the particle size distribution and the velocity of the particles. Measurement of the phase shift between the applied frequency and the detected Doppler shifted may be used to determine the direction of motion of the particles.

  8. Frequency Diversity Technique for Space-borne Radar Doppler Measurements

    Data.gov (United States)

    National Aeronautics and Space Administration — Doppler velocity measurement has been challenging for radars onboard fast moving platforms (such as spacecrafts) or radars with rapid scanning antennas due to the...

  9. GPM Ground Validation Doppler on Wheels (DOW) OLYMPEX V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The GPM Ground Validation Doppler on Wheels (DOW) OLYMPEX dataset was obtained by a dual-polarization and dual-frequency X-band mobile radar operated by the Center...

  10. Assimilation of Doppler weather radar observations in a mesoscale ...

    Indian Academy of Sciences (India)

    ) Doppler radar data in a numerical model for the prediction of mesoscale convective complexes around Chennai and Kolkata. Three strong convective events both over Chennai and Kolkata have been considered for the present study.

  11. Doppler Wind Lidar Measurements and Scalability to Space

    Data.gov (United States)

    National Aeronautics and Space Administration — Global measurements of wind speed and direction from Doppler wind lidars, if available, would significantly improve forecasting of severe weather events such as...

  12. Calculation of the Doppler broadening function using Fourier analysis

    International Nuclear Information System (INIS)

    Goncalves, Alessandro da Cruz

    2010-01-01

    An efficient and precise method for calculation of Doppler broadening function is very important to obtain average group microscopic cross sections, self shielding factors, resonance integrals and others reactor physics parameter. In this thesis two different methods for calculation of Doppler broadening function and interference term will be presented. The main method is based on a new integral form for Doppler broadening function ψ(x,ζ) which gives a mathematical interpretation of the approximation proposed by Bethe and Placzek, as the convolution of the Lorentzian function with a Gaussian function. This interpretation besides leading to a new integral form for ψ(x,ζ), enables to obtain a simple analytic solution for the Doppler broadening function. (author)

  13. Applicability of Doppler weather radar based rainfall data for runoff ...

    Indian Academy of Sciences (India)

    or flood-related studies in Indian river basins. A comparison study between. Doppler weather radar (DWR) derived rainfall data and the conventional rain gauge data was carried out with hourly inputs at one of the watersheds of Chennai basin,.

  14. Laser Doppler technology applied to atmospheric environmental operating problems

    Science.gov (United States)

    Weaver, E. A.; Bilbro, J. W.; Dunkin, J. A.; Jeffreys, H. B.

    1976-01-01

    Carbon dioxide laser Doppler ground wind data were very favorably compared with data from standard anemometers. As a result of these measurements, two breadboard systems were developed for taking research data: a continuous wave velocimeter and a pulsed Doppler system. The scanning continuous wave laser Doppler velocimeter developed for detecting, tracking and measuring aircraft wake vortices was successfully tested at an airport where it located vortices to an accuracy of 3 meters at a range of 150 meters. The airborne pulsed laser Doppler system was developed to detect and measure clear air turbulence (CAT). This system was tested aboard an aircraft, but jet stream CAT was not encountered. However, low altitude turbulence in cumulus clouds near a mountain range was detected by the system and encountered by the aircraft at the predicted time.

  15. NAMMA NASA POLARIMETRIC DOPPLER WEATHER RADAR (NPOL) V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The NAMMA NASA Polarimetric Doppler Weather Radar (NPOL) dataset used the NPOL, developed by a research team from Wallops Flight Facility, is a fully transportable...

  16. CAMEX-4 MIPS 915 MHZ DOPPLER WIND PROFILER V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The CAMEX-4 MIPS 915 MHZ Doppler Wind Profiler dataset was collected by the University of Alabama in Huntsville (UAH) Mobile Integrated Profiling System (MIPS),...

  17. Doppler electron velocimetry : notes on creating a practical tool.

    Energy Technology Data Exchange (ETDEWEB)

    Reu, Phillip L.; Milster, Tom (University of Arizona)

    2008-11-01

    The Doppler electron velocimeter (DEV) has been shown to be theoretically possible. This report attempts to answer the next logical question: Is it a practical instrument? The answer hinges upon whether enough electrons are available to create a time-varying Doppler current to be measured by a detector with enough sensitivity and bandwidth. The answer to both of these questions is a qualified yes. A target Doppler frequency of 1 MHz was set as a minimum rate of interest. At this target a theoretical beam current signal-to-noise ratio of 25-to-1 is shown for existing electron holography equipment. A detector is also demonstrated with a bandwidth of 1-MHz at a current of 10 pA. Additionally, a Linnik-type interferometer that would increase the available beam current is shown that would offer a more flexible arrangement for Doppler electron measurements over the traditional biprism.

  18. Thermal Design for a Diffraction-Limited Doppler Spectrometer

    Data.gov (United States)

    National Aeronautics and Space Administration — The Univ. of Notre Dame is building a new high-resolution spectrometer named “iLocater” to achieve unprecedented radial velocity (RV) precision for stellar Doppler...

  19. Muscle activity characterization by laser Doppler Myography

    International Nuclear Information System (INIS)

    Scalise, Lorenzo; Casaccia, Sara; Marchionni, Paolo; Ercoli, Ilaria; Tomasini, Enrico Primo

    2013-01-01

    Electromiography (EMG) is the gold-standard technique used for the evaluation of muscle activity. This technique is used in biomechanics, sport medicine, neurology and rehabilitation therapy and it provides the electrical activity produced by skeletal muscles. Among the parameters measured with EMG, two very important quantities are: signal amplitude and duration of muscle contraction, muscle fatigue and maximum muscle power. Recently, a new measurement procedure, named Laser Doppler Myography (LDMi), for the non contact assessment of muscle activity has been proposed to measure the vibro-mechanical behaviour of the muscle. The aim of this study is to present the LDMi technique and to evaluate its capacity to measure some characteristic features proper of the muscle. In this paper LDMi is compared with standard superficial EMG (sEMG) requiring the application of sensors on the skin of each patient. sEMG and LDMi signals have been simultaneously acquired and processed to test correlations. Three parameters has been analyzed to compare these techniques: Muscle activation timing, signal amplitude and muscle fatigue. LDMi appears to be a reliable and promising measurement technique allowing the measurements without contact with the patient skin

  20. Hydronephrosis and pregnancy: study with Doppler echography

    International Nuclear Information System (INIS)

    Ripolles Gonzalez, T.R.; Ambit Capdevilla, S.; Sanguesa Nebot, C.; Lazaro, S. de; Garcia Vila, J.H.; Belloch Ugarte, V.

    1993-01-01

    An 18-month study was performed to establish the normal intrarenal resistance index during pregnancy, in order to determine whether it differed significantly depending on the week of gestation or the degree of hydronephrosis. For this purpose , the flow velocity waves obtained in right kidney were analyzed in a group of 112 patients on the basis of 209 explorations. The kidneys were classified as grade 0,I,II, or III according to the degree of hydronephrosis. Doppler signal sampling was carried out at the level of the corticomedullary junction. From the results of the study it can be deduced that the index of intrarenal resistance during pregnancy is similar to that of the general population, that there are no significant differences among the groups with different degree of hydronephrosis and that the index does not vary according to the different weeks of gestation. These findings suggest that, during pregnancy, a pathological resistance index in a kidney should not be attributed to the physiological changes associated with normal gestation. (Author) 21 refs

  1. Muscle activity characterization by laser Doppler Myography

    Science.gov (United States)

    Scalise, Lorenzo; Casaccia, Sara; Marchionni, Paolo; Ercoli, Ilaria; Primo Tomasini, Enrico

    2013-09-01

    Electromiography (EMG) is the gold-standard technique used for the evaluation of muscle activity. This technique is used in biomechanics, sport medicine, neurology and rehabilitation therapy and it provides the electrical activity produced by skeletal muscles. Among the parameters measured with EMG, two very important quantities are: signal amplitude and duration of muscle contraction, muscle fatigue and maximum muscle power. Recently, a new measurement procedure, named Laser Doppler Myography (LDMi), for the non contact assessment of muscle activity has been proposed to measure the vibro-mechanical behaviour of the muscle. The aim of this study is to present the LDMi technique and to evaluate its capacity to measure some characteristic features proper of the muscle. In this paper LDMi is compared with standard superficial EMG (sEMG) requiring the application of sensors on the skin of each patient. sEMG and LDMi signals have been simultaneously acquired and processed to test correlations. Three parameters has been analyzed to compare these techniques: Muscle activation timing, signal amplitude and muscle fatigue. LDMi appears to be a reliable and promising measurement technique allowing the measurements without contact with the patient skin.

  2. Doppler time-of-flight imaging

    KAUST Repository

    Heide, Felix

    2015-07-30

    Over the last few years, depth cameras have become increasingly popular for a range of applications, including human-computer interaction and gaming, augmented reality, machine vision, and medical imaging. Many of the commercially-available devices use the time-of-flight principle, where active illumination is temporally coded and analyzed on the camera to estimate a per-pixel depth map of the scene. In this paper, we propose a fundamentally new imaging modality for all time-of-flight (ToF) cameras: per-pixel velocity measurement. The proposed technique exploits the Doppler effect of objects in motion, which shifts the temporal frequency of the illumination before it reaches the camera. Using carefully coded illumination and modulation frequencies of the ToF camera, object velocities directly map to measured pixel intensities. We show that a slight modification of our imaging system allows for color, depth, and velocity information to be captured simultaneously. Combining the optical flow computed on the RGB frames with the measured metric axial velocity allows us to further estimate the full 3D metric velocity field of the scene. We believe that the proposed technique has applications in many computer graphics and vision problems, for example motion tracking, segmentation, recognition, and motion deblurring.

  3. Intrahepatic portosystemic venous shunts: diagnosis by Doppler ultrasound; Cortocircuitos venosos portosistemicos intrahepaticos: diagnostico mediante ecografia Doppler

    Energy Technology Data Exchange (ETDEWEB)

    Garofano, M. P.; Medina, A.; Lopez, G.; Garrido, C. [Hospital Universitario Virgen de las Nieves. Granada (Spain)

    2001-07-01

    Intrahepatic portosystemic venous shunts are venous vascular lesions that allow intrahepatic portal vessels to communicate with hepatic veins. They may present in patients with portal hypertension or b discovered incidentally; it is considered that the latter may be congenital or acquired. A noninvasive methods. Doppler ultrasound aids in the diagnosis of these anomalous communications by providing images of the vessels and the direction, velocity and volume of the blood flow through the shunt. We present four cases of intrahepatic portosystemic venous shunt. (Author) 8 refs.

  4. Laser Doppler measurements in two-phase flows

    International Nuclear Information System (INIS)

    Durst, F.; Zare, M.

    1976-01-01

    Basic theory for laser-Doppler velocity measurements of large reflecting or refracting surfaces is provided. It is shown that the Doppler-signals contain information of the velocity and size of the large bodies, and relationships for transforming velocity and radius of curvature of moving spheres are presented. Preliminary experiments verified the analytical findings and demonstrated the applicability of the method to some two-phase flows

  5. Optimized variational analysis scheme of single Doppler radar wind data

    Science.gov (United States)

    Sasaki, Yoshi K.; Allen, Steve; Mizuno, Koki; Whitehead, Victor; Wilk, Kenneth E.

    1989-01-01

    A computer scheme for extracting singularities has been developed and applied to single Doppler radar wind data. The scheme is planned for use in real-time wind and singularity analysis and forecasting. The method, known as Doppler Operational Variational Extraction of Singularities is outlined, focusing on the principle of local symmetry. Results are presented from the application of the scheme to a storm-generated gust front in Oklahoma on May 28, 1987.

  6. Application of Total Variation Minimization to Doppler Tomography

    Directory of Open Access Journals (Sweden)

    M. Uemura

    2015-02-01

    Full Text Available We have developed a new model of the Doppler tomography using total variation minimization (DTTVM. We demonstrated that this method can reconstruct localized and non-axisymmetric profiles possibly having sharp edges in the Doppler map. We apply this model to the real data of the dwarf nova, WZ Sge in superoutburst. DTTVM can reproduce the observed spectra with a high precision, while the previous models fail to reproduce localized sources.

  7. Transcranial Doppler ultrasound and cerebral angiography - alternative or complementary

    International Nuclear Information System (INIS)

    Bockenheimer, S.; Lorey, N.

    1985-01-01

    Transcranial Doppler ultrasound is a noninvasive method of recording the flow velocity of larger intracranial vessels. The impact on diagnosis of cerebravascular occlusive disease is not yet evaluated. We present 15 patients, age range 39-73 years, who suffered from completed stroke. The findings of transcranial Doppler ultrasound and of cerebral angiography are presented. The value of both methods in treatment strategy is discussed. (orig.) [de

  8. Color doppler ultrasound diagonosis in cesarean scar pregnancy

    International Nuclear Information System (INIS)

    Chen Shanshan; Xia Fei; Shen Zongji; Xu Jianyin; Gu Xinxian

    2010-01-01

    Objective: To study the sonographic characteristics of cesarean scar pregnancy(CSP), and the value of color Doppler in the diagnosis of CSP. Methods: Twelve cases of CSP were all confirmed by transabdominal and transvaginal ultrasound. Results: The ultrasonogram of CSP could be divided into gestational sac type and mixed mass type. Conclusion: Color Doppler can give guidance to the early diagnosis, treatment and following-up of CSP because of the sonographic specifity of CSP. (authors)

  9. Doppler ultrasound in obstetrics and gynecology. 2. rev. and enl. ed.

    International Nuclear Information System (INIS)

    Maulik, D.

    2005-01-01

    The second edition of Doppler Ultrasound in Obstetrics and Gynecology has been expanded and comprehensively updated to present the current standards of practice in Doppler ultrasound and the most recent developments in the technology. Doppler Ultrasound in Obstetrics and Gynecology encompasses the full spectrum of clinical applications of Doppler ultrasound for the practicing obstetrician-gynecologist, including the latest advances in 3D and color Doppler and the newest techniques in 4D fetal echocardiography. Written by preeminent experts in the field, the book covers the basic and physical principles of Doppler ultrasound; the use of Doppler for fetal examination, including fetal cerebral circulation; Doppler echocardiography of the fetal heart; and the use of Doppler for postdated pregnancy and in cases of multiple gestation. Chapters on the use of Doppler for gynecologic investigation include ultrasound in ectopic pregnancy, for infertility, for benign disorders and for gynecologic malignancies. (orig.)

  10. Doppler ultrasound in obstetrics and gynecology. 2. rev. and enl. ed.

    Energy Technology Data Exchange (ETDEWEB)

    Maulik, D. [Winthrop Univ. Hospital, Mineola, NY (United States). Dept. of Obstetrics and Gynecology; Zalud, I. (eds.) [Kapiolani Medical Center for Women and Children, Honolulu, HI (United States)

    2005-07-01

    The second edition of Doppler Ultrasound in Obstetrics and Gynecology has been expanded and comprehensively updated to present the current standards of practice in Doppler ultrasound and the most recent developments in the technology. Doppler Ultrasound in Obstetrics and Gynecology encompasses the full spectrum of clinical applications of Doppler ultrasound for the practicing obstetrician-gynecologist, including the latest advances in 3D and color Doppler and the newest techniques in 4D fetal echocardiography. Written by preeminent experts in the field, the book covers the basic and physical principles of Doppler ultrasound; the use of Doppler for fetal examination, including fetal cerebral circulation; Doppler echocardiography of the fetal heart; and the use of Doppler for postdated pregnancy and in cases of multiple gestation. Chapters on the use of Doppler for gynecologic investigation include ultrasound in ectopic pregnancy, for infertility, for benign disorders and for gynecologic malignancies. (orig.)

  11. On the Potential Use of the Terminal Doppler Weather Radar Gust Front Detection Algorithm on the WSR-88D System. Part 2: Detecting Non-Gust Front Convergent Weather Phenomena

    Science.gov (United States)

    1991-10-01

    Wilson and Schreiber, 1986). In a similar instance, Roberts and Wilson (1989) show a DCVZ case where a terrain induced boundary dissipated (presumably...enhanced precipitation are commonly observed and they can vary in width, depth, length, strength, and location within a synoptic-scale storm ( Houze , et al...Doppler radar study of a warm frontal region. J. Atmos. Sci., 36, 2093-2107. Houze , R. A., P. V. Hobbs, K. Biswas, W. M. Davis, 1976: Mesoscale rain bands

  12. Low-Frequency Gravitational Wave Searches Using Spacecraft Doppler Tracking

    Directory of Open Access Journals (Sweden)

    Armstrong J. W.

    2006-01-01

    Full Text Available This paper discusses spacecraft Doppler tracking, the current-generation detector technology used in the low-frequency (~millihertz gravitational wave band. In the Doppler method the earth and a distant spacecraft act as free test masses with a ground-based precision Doppler tracking system continuously monitoring the earth-spacecraft relative dimensionless velocity $2 Delta v/c = Delta u/ u_0$, where $Delta u$ is the Doppler shift and $ u_0$ is the radio link carrier frequency. A gravitational wave having strain amplitude $h$ incident on the earth-spacecraft system causes perturbations of order $h$ in the time series of $Delta u/ u_0$. Unlike other detectors, the ~1-10 AU earth-spacecraft separation makes the detector large compared with millihertz-band gravitational wavelengths, and thus times-of-flight of signals and radio waves through the apparatus are important. A burst signal, for example, is time-resolved into a characteristic signature: three discrete events in the Doppler time series. I discuss here the principles of operation of this detector (emphasizing transfer functions of gravitational wave signals and the principal noises to the Doppler time series, some data analysis techniques, experiments to date, and illustrations of sensitivity and current detector performance. I conclude with a discussion of how gravitational wave sensitivity can be improved in the low-frequency band.

  13. Analysis of Radar Doppler Signature from Human Data

    Directory of Open Access Journals (Sweden)

    M. ANDRIĆ

    2014-04-01

    Full Text Available This paper presents the results of time (autocorrelation and time-frequency (spectrogram analyses of radar signals returned from the moving human targets. When a radar signal falls on the human target which is moving toward or away from the radar, the signals reflected from different parts of his body produce a Doppler shift that is proportional to the velocity of those parts. Moving parts of the body causes the characteristic Doppler signature. The main contribution comes from the torso which causes the central Doppler frequency of target. The motion of arms and legs induces modulation on the returned radar signal and generates sidebands around the central Doppler frequency, referred to as micro-Doppler signatures. Through analyses on experimental data it was demonstrated that the human motion signature extraction is better using spectrogram. While the central Doppler frequency can be determined using the autocorrelation and the spectrogram, the extraction of the fundamental cadence frequency using the autocorrelation is unreliable when the target is in the clutter presence. It was shown that the fundamental cadence frequency increases with increasing dynamic movement of people and simultaneously the possibility of its extraction is proportional to the degree of synchronization movements of persons in the group.

  14. Beam manipulating by metallic nano-slits with variant widths.

    Science.gov (United States)

    Shi, Haofei; Wang, Changtao; Du, Chunlei; Luo, Xiangang; Dong, Xiaochun; Gao, Hongtao

    2005-09-05

    A novel method is proposed to manipulate beam by modulating light phase through a metallic film with arrayed nano-slits, which have constant depth but variant widths. The slits transport electro-magnetic energy in the form of surface plasmon polaritons (SPPs) in nanometric waveguides and provide desired phase retardations of beam manipulating with variant phase propagation constant. Numerical simulation of an illustrative lens design example is performed through finite-difference time-domain (FDTD) method and shows agreement with theory analysis result. In addition, extraordinary optical transmission of SPPs through sub-wavelength metallic slits is observed in the simulation and helps to improve elements' energy using factor.

  15. Width of the confining string in Yang-Mills theory.

    Science.gov (United States)

    Gliozzi, F; Pepe, M; Wiese, U-J

    2010-06-11

    We investigate the transverse fluctuations of the confining string connecting two static quarks in (2+1)D SU(2) Yang-Mills theory using Monte Carlo calculations. The exponentially suppressed signal is extracted from the large noise by a very efficient multilevel algorithm. The resulting width of the string increases logarithmically with the distance between the static quark charges. Corrections at intermediate distances due to universal higher-order terms in the effective string action are calculated analytically. They accurately fit the numerical data.

  16. Bernstein width of a class of functions of finite smoothness

    Science.gov (United States)

    Kudryavtsev, S. N.

    1999-04-01

    A weak asymptotic formula is obtained for the Bernstein n-width in the space L_q(I^d) of the class F_p^{l,\\omega }(I^d) of functions on the cube I^d such that their generalized partial derivatives up to order l belong to L_p(I^d) and the moduli of continuity in the space L_p(I^d) of all their derivatives of order l are majorized by a fixed modulus of continuity \\omega.

  17. Orbit width scaling of TAE instability growth rate

    Energy Technology Data Exchange (ETDEWEB)

    Wong, H.V.; Berk, H.L.; Breizman, B.N.

    1995-07-01

    The growth rate of Toroidal Alfven Eigenmodes (TAE) driven unstable by resonant coupling of energetic charged particles is evaluated in the ballooning limit over a wide range of parameters. All damping effects are ignored. Variations in orbit width, aspect ratio, and the ratio of alfven velocity to energetic particle birth velocity, are explored. The relative contribution of passing and trapped particles, and finite Larmor radius effects, are also examined. The phase space location of resonant particles with interact strongly with the modes is described. The accuracy of the analytic results with respect to growth rate magnitude and parametric dependence is investigated by comparison with numerical results.

  18. Energy detection UWB system based on pulse width modulation

    Directory of Open Access Journals (Sweden)

    Song Cui

    2014-05-01

    Full Text Available A new energy detection ultra-wideband system based on pulse width modulation is proposed. The bit error rate (BER performance of this new system is slightly worst than that of a pulse position modulation (PPM system in additive white Gaussian noise channels. In multipath channels, this system does not suffer from cross-modulation interference as PPM, so it can achieve better BER performance than PPM when cross-modulation interference occurs. In addition, when synchronisation errors occur, this system is more robust than PPM.

  19. Pulse-width modulated DC-DC power converters

    CERN Document Server

    Kazimierczuk, Marian K

    2008-01-01

    This book studies switch-mode power supplies (SMPS) in great detail. This type of converter changes an unregulated DC voltage into a high-frequency pulse-width modulated (PWM) voltage controlled by varying the duty cycle, then changes the PWM AC voltage to a regulated DC voltage at a high efficiency by rectification and filtering. Used to supply electronic circuits, this converter saves energy and space in the overall system. With concept-orientated explanations, this book offers state-of-the-art SMPS technology and promotes an understanding of the principle operations of PWM converters,

  20. Crack widths in concrete with fibers and main reinforcement

    DEFF Research Database (Denmark)

    Christensen, Frede; Ulfkjær, Jens Peder; Brincker, Rune

    2015-01-01

    of the analytical model is to assume that the response of the structure can be described by the cracking response located within a fracture band. The model follows ideas previously used by other researchers in order to describe the fracture mechanics of concrete beams. These ideas are extended in this model to take...... relation is taken into account according to the crack width profile. Pullout of the main reinforcement is taken into account by assuming development of zones around the crack with constant friction stresses. In order to evaluate the capability of the model to produce reliable results, results are compared...

  1. New insights on dyke width and upward velocity

    Science.gov (United States)

    Taisne, B.; Jaupart, C.; Tait, S.

    2012-04-01

    Striking observations have been made that challenge our understanding of magma migration through the Earth's crust. How may a volatile rich magma stall at shallow depth as a growing crypto-dome such as during the 1980 Mount Saint Helens eruption? How can we explain the width of the 2005 mega-dyke intrusion in Afar, that attained more than 8 meters with a very small amount of magma emitted at the surface? We show that changes in the geometry and the dynamics of the propagation can be attributed to density variations in the host rocks, to solidification, to volatile exsolution and expansion or to changes in the input flux of magma at depth. We focus on the relationship between dyke width and ascent rate. Shallow levels are commonly made of low density rocks or volcanic deposits with strong impact on dyke ascent. The dynamics and width of the upper part of the dyke (the nose region) are determined by a local buoyancy balance, independently of the total buoyancy of the magma column between source and tip. In such conditions, the dyke swells and slows down and, in some cases, may not breach the surface. Using laboratory experiments we show that solidification of the magma may lead to a regime of intermittent propagation, even with constant physical conditions at the source. Interestingly the time between two steps can be related to the input flux at the source region. With volatile-bearing magmas, dyke propagation proceeds in two markedly different ways depending on whether or not fragmentation occurs. With no fragmentation, magma expansion leads to acceleration and thinning of the dyke. With fragmentation, the sharp drop of head loss that occurs in gas-rich fragmented material generates large internal overpressure and swelling of the nose region, leading to deceleration of the dyke. All the above effects lead to rapid and large changes of ascent rate. Large variations of magma flux at the source would be required to have similar impacts on dyke propagation. In an

  2. Calculation of the Doppler broadening function using Fourier analysis;Calculo da funcao de alargamento Doppler utilizando analise de Fourier

    Energy Technology Data Exchange (ETDEWEB)

    Goncalves, Alessandro da Cruz

    2010-07-01

    An efficient and precise method for calculation of Doppler broadening function is very important to obtain average group microscopic cross sections, self shielding factors, resonance integrals and others reactor physics parameter. In this thesis two different methods for calculation of Doppler broadening function and interference term will be presented. The main method is based on a new integral form for Doppler broadening function {psi}(x,{zeta}) which gives a mathematical interpretation of the approximation proposed by Bethe and Placzek, as the convolution of the Lorentzian function with a Gaussian function. This interpretation besides leading to a new integral form for {psi}(x,{zeta}), enables to obtain a simple analytic solution for the Doppler broadening function. (author)

  3. Agricultural pesticide residues

    International Nuclear Information System (INIS)

    Fuehr, F.

    1984-01-01

    The utilization of tracer techniques in the study of agricultural pesticide residues is reviewed under the following headings: lysimeter experiments, micro-ecosystems, translocation in soil, degradation of pesticides in soil, biological availability of soil-applied substances, bound residues in the soil, use of macro- and microautography, double and triple labelling, use of tracer labelling in animal experiments. (U.K.)

  4. The effect of residual ventricular septal defects on early clinical outcome: initial experience

    International Nuclear Information System (INIS)

    Zaman, H.; Cheema, M.A.; Jalal, A.

    2000-01-01

    Residual ventricular septal defect (VSD)after repair of isolated VSD or Fallot's tetralogy is one of the main causes of morbidity and re-operations. In this paper we have presented the results of out initial experience regarding the management of this problem. The data consists of 71 patients (22 isolated VSD and 29 fallout's tetralogy) operate during January 1991 to July, 1993. The incidence of residual VSD as shown by color doppler study at the time of discharge from hospital and at three month's follow-up was 3 out of 60 patients(73%) and 12 out of to (20%) respectively. Six out of these 12 patients were NYHA class III-IV who underwent cardiac catheterization which revealed patch dehiscence in two patients and residual right ventricular outflow tract obstruction in four patients. The two patients, with patch dehiscence were reported successfully with very good outcome. Simple color doppler mapping tends to over-diagnose residual VSDs since it can pick up small haemodynamically insignificant leaks around stitches and needle holes which seal off in due course. The findings of color doppler should, therefore, be correlated with actual clinical outcome in order to proceed with further investigation and re-operation. (author)

  5. Investigations into the residual strength of a 2.5 m wide Bushveld Merensky Reef crush pillar

    CSIR Research Space (South Africa)

    Watson, BP

    2008-08-01

    Full Text Available .2 m.The residual strength of the crush pillar with a width of 2.5 m was determined from a series of strain measurements in two boreholes and a Boussinesq matrix inversion. The calculated peak and residual stresses of the pillar were surprisingly high...

  6. A prospective analysis of free flap monitoring techniques: physical examination, external Doppler, implantable Doppler, and tissue oximetry.

    Science.gov (United States)

    Lohman, Robert F; Langevin, Claude-Jean; Bozkurt, Mehmet; Kundu, Neilendu; Djohan, Risal

    2013-01-01

    No universally accepted method of flap monitoring exists, and several techniques are in use. Repeated physical examination is most popular and is often supplemented with a handheld, external Doppler, and/or implantable Doppler probes; near-infrared spectroscopy is less commonly used. We investigated the nursing and resident house staff's experience and confidence with physical exam for flap monitoring. Also, a consecutive series of 38 patients with free flaps were monitored using physical examination, external Doppler, implantable arterial and venous Doppler probes, and near-infrared spectroscopy. Five patients developed signs of microvascular complications within 3 days of surgery; all were explored and salvaged. Neither the residents nor the nursing staff were universally trained or experienced in flap monitoring by physical exam. In all patients, changes in the appearance of the flap suggestive of a microvascular complication lagged 30 to 60 minutes after the adjunctive monitoring methods indicated that a problem had occurred. Near-infrared spectroscopy was the first warning sign in four of the five patients. Two patients were explored before thrombosis of the anastomoses occurred. Near-infrared spectroscopy may identify early microvascular complications more reliably than physical examination, external Doppler, or implantable Doppler. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  7. Analysis of airborne Doppler lidar, Doppler radar and tall tower measurements of atmospheric flows in quiescent and stormy weather

    Science.gov (United States)

    Bluestein, H. B.; Doviak, R. J.; Eilts, M. D.; Mccaul, E. W.; Rabin, R.; Sundara-Rajan, A.; Zrnic, D. S.

    1986-01-01

    The first experiment to combine airborne Doppler Lidar and ground-based dual Doppler Radar measurements of wind to detail the lower tropospheric flows in quiescent and stormy weather was conducted in central Oklahoma during four days in June-July 1981. Data from these unique remote sensing instruments, coupled with data from conventional in-situ facilities, i.e., 500-m meteorological tower, rawinsonde, and surface based sensors, were analyzed to enhance understanding of wind, waves and turbulence. The purposes of the study were to: (1) compare winds mapped by ground-based dual Doppler radars, airborne Doppler lidar, and anemometers on a tower; (2) compare measured atmospheric boundary layer flow with flows predicted by theoretical models; (3) investigate the kinematic structure of air mass boundaries that precede the development of severe storms; and (4) study the kinematic structure of thunderstorm phenomena (downdrafts, gust fronts, etc.) that produce wind shear and turbulence hazardous to aircraft operations. The report consists of three parts: Part 1, Intercomparison of Wind Data from Airborne Lidar, Ground-Based Radars and Instrumented 444 m Tower; Part 2, The Structure of the Convective Atmospheric Boundary Layer as Revealed by Lidar and Doppler Radars; and Part 3, Doppler Lidar Observations in Thunderstorm Environments.

  8. Measurement of the Higgs decay width in the diphoton channel

    CERN Document Server

    Adolfsson, Jonatan

    2014-01-01

    In this note, a projected measurement of the Higgs decay width ($\\Gamma_{H}$) is presented, based on interference in the diphoton channel. Two different hypotheses were tested. Hypothesis A assumes that the $H\\to\\gamma\\gamma$ cross-section is proportional to $\\Gamma_{H}^{-1}$, whereas hypothesis B assumes that this cross-section is constant and instead uses the overall change in $m_{\\gamma\\gamma}$ line shape. Events were simulated using Sherpa 2.1, and were used to produce test statistics in order to obtain a 95 % confidence limit of $\\Gamma_{H}$. The standard model width was tested using Asimov data sets, which were validated using pseudo-experiments for the integrated luminosities of Run 1, Run 2 and HL-LHC. The obtained limits are significantly improved with respect to previous studies, but further validations of the test are required. The expected limits for 300 fb$^{-1}$ are $1.19\\times\\Gamma_{H\\,SM}$ for hypothesis A and $24\\times\\Gamma_{H\\,SM}$ for hypothesis B.

  9. Baryon Masses and Hadronic Decay Widths with Explicit Pionic Contributions

    International Nuclear Information System (INIS)

    Schmidt, R. A.; Plessas, W.; Schweiger, W.; Canton, L.

    2017-01-01

    We report results from studies of baryon ground and resonant states by taking explicit mesonic degrees of freedom into account. We are following a relativistic coupled-channels approach relying on a Poincaré-invariant mass operator in matrix form. Generally, it corresponds to a bare particle that is coupled to a number of further mesonic channels. Here we present results, where the bare particle is either a bare nucleon or a bare Delta coupled to pion–nucleon and pion–Delta channels, respectively. For the pion–baryon vertices we employ coupling constants and form factors from different models in the literature. From the mass-operator eigenvalue equation we obtain the pion-dressing effects on the nucleon mass as well as the mass and pion-decay width of the Delta. The dressed masses become smaller than the bare ones, and a finite width of the Delta is naturally generated. The results are relevant for the construction of constituent-quark models for baryons, which have so far not included explicit mesonic degrees of freedom, but have rather relied on three-quark configurations only. (author)

  10. Direct top-quark width measurement at CDF.

    Science.gov (United States)

    Aaltonen, T; Álvarez González, B; Amerio, S; Amidei, D; Anastassov, A; Annovi, A; Antos, J; Apollinari, G; Appel, J A; Apresyan, A; Arisawa, T; Artikov, A; Asaadi, J; Ashmanskas, W; Auerbach, B; Aurisano, A; Azfar, F; Badgett, W; Barbaro-Galtieri, A; Barnes, V E; Barnett, B A; Barria, P; Bartos, P; Bauce, M; Bauer, G; Bedeschi, F; Beecher, D; Behari, S; Bellettini, G; Bellinger, J; Benjamin, D; Beretvas, A; Bhatti, A; Binkley, M; Bisello, D; Bizjak, I; Bland, K R; Blocker, C; Blumenfeld, B; Bocci, A; Bodek, A; Bortoletto, D; Boudreau, J; Boveia, A; Brau, B; Brigliadori, L; Brisuda, A; Bromberg, C; Brucken, E; Bucciantonio, M; Budagov, J; Budd, H S; Budd, S; Burkett, K; Busetto, G; Bussey, P; Buzatu, A; Cabrera, S; Calancha, C; Camarda, S; Campanelli, M; Campbell, M; Canelli, F; Canepa, A; Carls, B; Carlsmith, D; Carosi, R; Carrillo, S; Carron, S; Casal, B; Casarsa, M; Castro, A; Catastini, P; Cauz, D; Cavaliere, V; Cavalli-Sforza, M; Cerri, A; Cerrito, L; Chen, Y C; Chertok, M; Chiarelli, G; Chlachidze, G; Chlebana, F; Cho, K; Chokheli, D; Chou, J P; Chung, W H; Chung, Y S; Ciobanu, C I; Ciocci, M A; Clark, A; Clark, D; Compostella, G; Convery, M E; Conway, J; Corbo, M; Cordelli, M; Cox, C A; Cox, D J; Crescioli, F; Cuenca Almenar, C; Cuevas, J; Culbertson, R; Dagenhart, D; d'Ascenzo, N; Datta, M; de Barbaro, P; De Cecco, S; De Lorenzo, G; Dell'Orso, M; Deluca, C; Demortier, L; Deng, J; Deninno, M; Devoto, F; d'Errico, M; Di Canto, A; Di Ruzza, B; Dittmann, J R; D'Onofrio, M; Donati, S; Dong, P; Dorigo, T; Ebina, K; Elagin, A; Eppig, A; Erbacher, R; Errede, D; Errede, S; Ershaidat, N; Eusebi, R; Fang, H C; Farrington, S; Feindt, M; Fernandez, J P; Ferrazza, C; Field, R; Flanagan, G; Forrest, R; Frank, M J; Franklin, M; Freeman, J C; Furic, I; Gallinaro, M; Galyardt, J; Garcia, J E; Garfinkel, A F; Garosi, P; Gerberich, H; Gerchtein, E; Giagu, S; Giakoumopoulou, V; Giannetti, P; Gibson, K; Ginsburg, C M; Giokaris, N; Giromini, P; Giunta, M; Giurgiu, G; Glagolev, V; Glenzinski, D; Gold, M; Goldin, D; Goldschmidt, N; Golossanov, A; Gomez, G; Gomez-Ceballos, G; Goncharov, M; González, O; Gorelov, I; Goshaw, A T; Goulianos, K; Gresele, A; Grinstein, S; Grosso-Pilcher, C; Guimaraes da Costa, J; Gunay-Unalan, Z; Haber, C; Hahn, S R; Halkiadakis, E; Hamaguchi, A; Han, J Y; Happacher, F; Hara, K; Hare, D; Hare, M; Harr, R F; Hatakeyama, K; Hays, C; Heck, M; Heinrich, J; Herndon, M; Hewamanage, S; Hidas, D; Hocker, A; Hopkins, W; Horn, D; Hou, S; Hughes, R E; Hurwitz, M; Husemann, U; Hussain, N; Hussein, M; Huston, J; Introzzi, G; Iori, M; Ivanov, A; James, E; Jang, D; Jayatilaka, B; Jeon, E J; Jha, M K; Jindariani, S; Johnson, W; Jones, M; Joo, K K; Jun, S Y; Junk, T R; Kamon, T; Karchin, P E; Kato, Y; Ketchum, W; Keung, J; Khotilovich, V; Kilminster, B; Kim, D H; Kim, H S; Kim, H W; Kim, J E; Kim, M J; Kim, S B; Kim, S H; Kim, Y K; Kimura, N; Klimenko, S; Kondo, K; Kong, D J; Konigsberg, J; Korytov, A; Kotwal, A V; Kreps, M; Kroll, J; Krop, D; Krumnack, N; Kruse, M; Krutelyov, V; Kuhr, T; Kurata, M; Kwang, S; Laasanen, A T; Lami, S; Lammel, S; Lancaster, M; Lander, R L; Lannon, K; Lath, A; Latino, G; Lazzizzera, I; LeCompte, T; Lee, E; Lee, H S; Lee, J S; Lee, S W; Leo, S; Leone, S; Lewis, J D; Lin, C-J; Linacre, J; Lindgren, M; Lipeles, E; Lister, A; Litvintsev, D O; Liu, C; Liu, Q; Liu, T; Lockwitz, S; Lockyer, N S; Loginov, A; Lucchesi, D; Lueck, J; Lujan, P; Lukens, P; Lungu, G; Lys, J; Lysak, R; Madrak, R; Maeshima, K; Makhoul, K; Maksimovic, P; Malik, S; Manca, G; Manousakis-Katsikakis, A; Margaroli, F; Marino, C; Martínez, M; Martínez-Ballarín, R; Mastrandrea, P; Mathis, M; Mattson, M E; Mazzanti, P; McFarland, K S; McIntyre, P; McNulty, R; Mehta, A; Mehtala, P; Menzione, A; Mesropian, C; Miao, T; Mietlicki, D; Mitra, A; Miyake, H; Moed, S; Moggi, N; Mondragon, M N; Moon, C S; Moore, R; Morello, M J; Morlock, J; Movilla Fernandez, P; Mukherjee, A; Muller, Th; Murat, P; Mussini, M; Nachtman, J; Nagai, Y; Naganoma, J; Nakano, I; Napier, A; Nett, J; Neu, C; Neubauer, M S; Nielsen, J; Nodulman, L; Norniella, O; Nurse, E; Oakes, L; Oh, S H; Oh, Y D; Oksuzian, I; Okusawa, T; Orava, R; Ortolan, L; Pagan Griso, S; Pagliarone, C; Palencia, E; Papadimitriou, V; Paramonov, A A; Patrick, J; Pauletta, G; Paulini, M; Paus, C; Pellett, D E; Penzo, A; Phillips, T J; Piacentino, G; Pianori, E; Pilot, J; Pitts, K; Plager, C; Pondrom, L; Potamianos, K; Poukhov, O; Prokoshin, F; Pronko, A; Ptohos, F; Pueschel, E; Punzi, G; Pursley, J; Rahaman, A; Ramakrishnan, V; Ranjan, N; Redondo, I; Renton, P; Rescigno, M; Rimondi, F; Ristori, L; Robson, A; Rodrigo, T; Rodriguez, T; Rogers, E; Rolli, S; Roser, R; Rossi, M; Ruffini, F; Ruiz, A; Russ, J; Rusu, V; Safonov, A; Sakumoto, W K; Santi, L; Sartori, L; Sato, K; Saveliev, V; Savoy-Navarro, A; Schlabach, P; Schmidt, A; Schmidt, E E; Schmidt, M P; Schmitt, M; Schwarz, T

    2010-12-03

    We present a measurement of the top-quark width in the lepton+jets decay channel of tt events produced in p p collisions at Fermilab's Tevatron collider and collected by the CDF II detector. From a data sample corresponding to 4.3 fb(-1) of integrated luminosity, we identify 756 candidate events. The top-quark mass and the mass of the hadronically decaying W boson that comes from the top-quark decay are reconstructed for each event and compared with templates of different top-quark widths (Γ(t)) and deviations from nominal jet energy scale (Δ(JES)) to perform a simultaneous fit for both parameters, where Δ(JES) is used for the in situ calibration of the jet energy scale. By applying a Feldman-Cousins approach, we establish an upper limit at 95% confidence level (CL) of Γ(t) quark mass of 172.5 GeV/c(2), which are consistent with the standard model prediction.

  11. Tooth width predictions in a sample of Black South Africans.

    Science.gov (United States)

    Khan, M I; Seedat, A K; Hlongwa, P

    2007-07-01

    Space analysis during the mixed dentition requires prediction of the mesiodistal widths of the unerupted permanent canines and premolars and prediction tables and equations may be used for this purpose. The Tanaka and Johnston prediction equations, which were derived from a North American White sample, is one example which is widely used. This prediction equation may be inapplicable to other race groups due to racial tooth size variability. Therefore the purpose of this study was to derive prediction equations that would be applicable to Black South African subjects. One hundred and ten pre-treatment study casts of Black South African subjects were analysed from the Department of Orthodontics' records at the University of Limpopo. The sample was equally divided by gender with all subjects having Class I molar relationship and relatively well aligned teeth. The mesiodistal widths of the maxillary and mandibular canines and premolars were measured with a digital vernier calliper and compared with the measurements predicted with the Tanaka and Johnston equations. The relationship between the measured and predicted values were analysed by correlation and regression analyses. The results indicated that the Tanaka and Johnston prediction equations were not fully applicable to the Black South African sample. The equations tended to underpredict the male sample, while slight overprediction was observed in the female sample. Therefore, new equations were formulated and proposed that would be accurate for Black subjects.

  12. Determination of the width of the top quark

    Energy Technology Data Exchange (ETDEWEB)

    Abazov, Victor Mukhamedovich; /Dubna, JINR; Abbott, Braden Keim; /Oklahoma U.; Abolins, Maris A.; /Michigan State U.; Acharya, Bannanje Sripath; /Tata Inst.; Adams, Mark Raymond; /Illinois U., Chicago; Adams, Todd; /Florida State U.; Alexeev, Guennadi D.; /Dubna, JINR; Alkhazov, Georgiy D.; /St. Petersburg, INP; Alton, Andrew K.; /Michigan U. /Augustana Coll., Sioux Falls; Alverson, George O.; /Northeastern U.; Alves, Gilvan Augusto; /Rio de Janeiro, CBPF /Nijmegen U.

    2010-09-01

    We extract the total width of the top quark, {Lambda}{sub t}, from the partial decay width {Lambda}(t {yields} Wb) measured using the t-channel cross section for single top quark production and from the branching fraction B(t {yields} Wb) measured in t{bar t} events using up to 2.3 fb{sup -1} of integrated luminosity collected by the D0 Collaboration at the Tevatron p{bar p} Collider. The result is {Lambda}{sub t} = 1.99{sub -0.55}{sup +0.69} GeV, which translates to a top-quark lifetime of {tau}{sub t} = (3.3{sub -0.9}{sup +1.3}) x 10{sup -25} s. Assuming a high mass fourth generation b{prime} quark and unitarity of the four-generation quark-mixing matrix, we set the first upper limit on |V{sub tb{prime}}| < 0.63 at 95% C.L.

  13. Sub-Doppler Spectroscopy of H_3^+

    Science.gov (United States)

    Hodges, James N.; Perry, Adam J.; Siller, Brian M.; McCall, Benjamin J.

    2013-06-01

    Spectroscopy of H_3^+ is of fundamental interest for advancing ab initio efforts to calculate spectra with high precision and accuracy. H_3^+ is the simplest polyatomic ion, which is why it is an excellent benchmark for theory. In order to perform calculations with spectroscopic accuracy, relativistic and non-adiabatic corrections to the Born-Oppenhiemer approximation must be included; calculations with these considerations agree to within hundredths of a wavenumber. Increasing the precision of the calculations further will require a treatment of quantum electrodynamic effects, as has already been implemented for the diatomic case, and testing these calculations will require higher-precision experimental data to guide ab initio calculations. Noise Immune Cavity Enhanced Optical Heterodyne Velocity Modulation Spectroscopy, or NICE-OHVMS, is a highly sensitive, highly precise technique that we have employed to observe transitions in the ν_2 fundamental band of H_3^+. It combines the advantages of cavity enhancement and heterodyne detection with the ion-neutral discrimination afforded by velocity modulation. Combining a cavity with a high power mid-infrared light source, we can saturate rovibrational transitions. The resulting Lamb dips may be fit in order to determine line centers to a much higher precision than is possible for ordinary Doppler broadened profiles. Additionally, a frequency comb is used to surpass the limited accuracy and precision of a wavemeter. Here we present the results from comb calibrated H_3^+ transitions observed via NICE-OHVMS. Precision and accuracy of ˜ 1 MHz were achieved representing the most accurate and precise H_3^+ line list that has been obtained to date. O. L. Polyansky, J. Tennyson, J. Chem. Phys. (1999), 110, 5056--5064. J. Komasa, et al. J. Chem. Theor. Comp. (2011), 7, 3105--3115. B. M. Siller, et al. Opt. Express (2011), 19, 24822--7. K. N. Crabtree, et al. Chem. Phys. Lett. (2012), 551, 1--6.

  14. Requirements to gap widths and clamping for CO2 laser butt welding

    DEFF Research Database (Denmark)

    Gong, Hui; Juhl, Thomas Winther

    1999-01-01

    In the experimental study of fixturing and gap width requirements a clamping device for laser butt welding of steel sheets has been developed and tested. It has fulfilled the work and made the gap width experiments possible.It has shown that the maximum allowable gap width to some extent is inver......In the experimental study of fixturing and gap width requirements a clamping device for laser butt welding of steel sheets has been developed and tested. It has fulfilled the work and made the gap width experiments possible.It has shown that the maximum allowable gap width to some extent...

  15. Longitudinal study of aortic isthmus Doppler in appropriately grown and small-for-gestational-age fetuses with normal and abnormal umbilical artery Doppler.

    LENUS (Irish Health Repository)

    Kennelly, M M

    2012-04-01

    To establish reference ranges using longitudinal data for aortic isthmus (AoI) Doppler indices in appropriate-for-gestational-age (AGA) fetuses and to document the longitudinal trends in a cohort of small-for-gestational-age (SGA) fetuses with normal umbilical artery Doppler and in fetuses with intrauterine growth restriction (IUGR) and abnormal umbilical artery Doppler.

  16. Handling of Solid Residues

    International Nuclear Information System (INIS)

    Medina Bermudez, Clara Ines

    1999-01-01

    The topic of solid residues is specifically of great interest and concern for the authorities, institutions and community that identify in them a true threat against the human health and the atmosphere in the related with the aesthetic deterioration of the urban centers and of the natural landscape; in the proliferation of vectorial transmitters of illnesses and the effect on the biodiversity. Inside the wide spectrum of topics that they keep relationship with the environmental protection, the inadequate handling of solid residues and residues dangerous squatter an important line in the definition of political and practical environmentally sustainable. The industrial development and the population's growth have originated a continuous increase in the production of solid residues; of equal it forms, their composition day after day is more heterogeneous. The base for the good handling includes the appropriate intervention of the different stages of an integral administration of residues, which include the separation in the source, the gathering, the handling, the use, treatment, final disposition and the institutional organization of the administration. The topic of the dangerous residues generates more expectation. These residues understand from those of pathogen type that are generated in the establishments of health that of hospital attention, until those of combustible, inflammable type, explosive, radio-active, volatile, corrosive, reagent or toxic, associated to numerous industrial processes, common in our countries in development

  17. Formation of high quality interference fringes from both sides of a suitably designed hololens in the laser Doppler anemometer measurement volume

    Science.gov (United States)

    Ghosh, Abhijit; Nirala, A. K.

    2017-11-01

    We report, for the first time to the best of our knowledge, the formation of high quality, evenly spaced, undistorted fringes in the measurement volume of a laser Doppler anemometer from both sides of a suitably designed hololens. Experiments are performed for the analysis of fringes formed at the measurement volume by real time monitoring and actual fringe field analysis techniques. The results indicate the qualitative as well as quantitative improvement of 66.58 % in overall average normalised standard deviations of the width of the fringes formed by the proposed imaging configuration than that of the conventional imaging configuration.

  18. Comparison between oscillometric- and Doppler-ABI in elderly individuals

    Directory of Open Access Journals (Sweden)

    Takahashi I

    2013-03-01

    Full Text Available Ikuno Takahashi,1,3 Kyoji Furukawa,2 Waka Ohishi,1 Tetsuya Takahashi,3 Masayasu Matsumoto,3 Saeko Fujiwara11Department of Clinical Studies, 2Department of Statistics, Radiation Effects Research Foundation (RERF, Hiroshima, Japan; 3Department of Clinical Neuroscience and Therapeutics, Hiroshima University, Hiroshima, JapanAbstract: Peripheral arterial disease (PAD generally remains under-recognized, mainly due to the specialized technical skills required to detect the low values of the ankle-brachial index (ABI. As a simpler and faster alternative to the standard method using continuous-wave Doppler ultrasound, we evaluated automated oscillometric ABI measurement by VP-2000 with an elderly cohort of 113 subjects (age range, 61 to 88 years. The standard deviation in ABIs measured by the Doppler method was statistically greater than that measured by the oscillometric method for each of the two legs (P < 0.001. Correlations in ABIs between the two methods were 0.46 for the left leg and 0.61 for the right leg; this result appears to have been caused by interobserver variation in the Doppler ABI measurements. While the trend showing greater differences between average oscillometric- and Doppler-ABIs was significant at the lower ABI ranges, there was little indication of differences in measurements having an average ABI > 1.1. The difference between the methods was suggestively larger in subjects who were smokers than in non-smokers (P = 0.09, but the difference was not affected by other potential atherosclerotic risk factors, including age at examination (P > 0.50. A larger difference at lower ABIs led to better PAD detection by the Doppler method compared to the oscillometric method (sensitivity = 50%, specificity = 100%, although the overall agreement was not small (Cohen's Kappa = 0.65. Our findings indicate that oscillometric devices can provide more accurate estimation of the prevalence of PAD in elderly individuals than the conventional Doppler

  19. Cross-correlation Doppler global velocimetry (CC-DGV)

    Science.gov (United States)

    Cadel, Daniel R.; Lowe, K. Todd

    2015-08-01

    A flow velocimetry method, cross-correlation Doppler global velocimetry (CC-DGV), is presented as a robust, simplified, and high dynamic range implementation of the Doppler global/planar Doppler velocimetry technique. A sweep of several gigahertz of the vapor absorption spectrum is used for each velocity sample, with signals acquired from both Doppler-shifted scattered light within the flow and a non-Doppler shifted reference beam. Cross-correlation of these signals yields the Doppler shift between them, averaged over the duration of the scan. With presently available equipment, velocities from 0 ms-1 to over 3000 ms-1 can notionally be measured simultaneously, making the technique ideal for high speed flows. The processing routine is shown to be robust against large changes in the vapor pressure of the iodine cell, benefiting performance of the system in facilities where ambient conditions cannot be easily regulated. Validation of the system was performed with measurements of a model wind turbine blade boundary layer made in a 1.83 m by 1.83 m subsonic wind tunnel for which laser Doppler velocimetry (LDV) measurements were acquired alongside the CC-DGV results. CC-DGV uncertainties of ±1.30 ms-1, ±0.64 ms-1, and ±1.11 ms-1 were determined for the orthogonal stream-wise, transverse-horizontal, and transverse-vertical velocity components, and root-mean-square deviations of 2.77 ms-1 and 1.34 ms-1 from the LDV validation results were observed for Reynolds numbers of 1.5 million and 2 million, respectively. Volumetric mean velocity measurements are also presented for a supersonic jet, with velocity uncertainties of ±4.48 ms-1, ±16.93 ms-1, and ±0.50 ms-1 for the orthogonal components, and self-validation done by collapsing the data with a physical scaling.

  20. The 3 December 2015 paroxysm of Voragine crater at Etna: insights from Doppler radar measurements

    Science.gov (United States)

    Donnadieu, Franck; Freret-Lorgeril, Valentin; Gouhier, Mathieu; Coltelli, Mauro; Scollo, Simona; Fréville, Patrick; Hervier, Claude; Prestifilippo, Michele

    2016-04-01

    After a progressive intensification of Strombolian activity inside the Voragine crater in the evening of December 2 2015, Mount Etna produced a short but violent paroxysm in the night of 3 December 2015, the most intense of the last two decades at Voragine. Lava fountains, observed with the network of thermal and visible cameras of INGV-OE, reached well over 1 km in height with some jets of incandescent material reaching 3 km. A tephra column several kilometers high was produced and pyroclastic material was dispersed by winds in altitude to the NE, causing ash fallouts to affect many towns in Sicily and Reggio Calabria. A 23 cm-wavelength Doppler radar (VOLDORAD 2B), located about 3 km from NSEC at the Montagnola station and integrated into the INGV-OE instrumental network, has been continuously monitoring the explosive activity of Mt. Etna's summit craters since 2009. The radar beam probes 13 successive volumes 150 m deep aligned northward above the summit craters, providing two sets of parameters (echo power and velocity) at a rate of 0.2 s. We analyze the paroxysmal event of Voragine using the radar echoes and Doppler signals coming from volumes inside the lava fountain feeding the tephra column in combination with thermal and visible imagery and satellite data. The radar range gating allowed us to immediately discriminate the central craters as the source of the tephra emission and to estimate the lava fountain width between 300 and 450 m. The backscattered power, which is related to the erupted tephra mass load in the beam, and Doppler velocities help to mark the transition from Strombolian activity to lava fountaining, providing onset and end times of the fountain. The tephra flux into the radar beam started to increase after 02:00 UTC with a strong increase at 02:20 UTC marking the transition to continuous lava fountaining. The climax was reached between ca. 02:35 and 03:15 UTC with maintained high echo power and ejection velocities of 190 m/s in average

  1. Energy and energy width measurement in the FNAL antiproton accumulator

    International Nuclear Information System (INIS)

    Church, M.; Hsueh, S.; Rapidis, P.; Werkema, S.

    1991-10-01

    The Fermilab Antiproton Accumulator has recently been used to produce Charmonium resonances (charm quark, anti-charm quark bound states) in proton-antiproton annihilations using an internal H 2 gas jet target. A measurement of the resonance mass and width may be obtained from a precise knowledge of the antiproton beam energy and energy spread. The beam energy is measured to an accuracy of 1 part in 10 4 in the range 6.3 Gev to 4.1 Gev by measuring the orbit length and revolution frequency of the beam. The beam momentum spread is measured to an accuracy of 10% by measuring the beam frequency spread and the parameter η = (P beam /F rev )·(dF rev /dP beam ). These two measurement techniques are described in this report

  2. Energy and energy width measurement in the FNAL antiproton accumulator

    Energy Technology Data Exchange (ETDEWEB)

    Church, M.; Hsueh, S.; Rapidis, P.; Werkema, S.

    1991-10-01

    The Fermilab Antiproton Accumulator has recently been used to produce Charmonium resonances (charm quark, anti-charm quark bound states) in proton-antiproton annihilations using an internal H{sub 2} gas jet target. A measurement of the resonance mass and width may be obtained from a precise knowledge of the antiproton beam energy and energy spread. The beam energy is measured to an accuracy of 1 part in 10{sup 4} in the range 6.3 Gev to 4.1 Gev by measuring the orbit length and revolution frequency of the beam. The beam momentum spread is measured to an accuracy of 10% by measuring the beam frequency spread and the parameter {eta} = (P{sub beam}/F{sub rev}){center_dot}(dF{sub rev}/dP{sub beam}). These two measurement techniques are described in this report.

  3. Free-edge delamination - Laminate width and loading conditions effects

    Science.gov (United States)

    Murthy, Pappu L. N.; Chamis, Christos C.

    1989-01-01

    The width and loading conditions effects on free-edge stress fields in composite laminates are investigated using a three-dimensional finite element analysis. This analysis includes a special free-edge region refinement or superelement with progressive substructuring (mesh refinement) and finite thickness interply layers. The different loading conditions include in-plane and out-of-plane bending, combined axial tension and in-plane shear, twisting, uniform temperature and uniform moisture. Results obtained indicate that: axial tension causes the smallest magnitude of interlaminar free edge stress compared to other loading conditions; free-edge delamination data obtained from laboratory specimens cannot be scaled to structural components; and composite structural components are not likely to delaminate.

  4. [Residual neuromuscular blockade].

    Science.gov (United States)

    Fuchs-Buder, T; Schmartz, D

    2017-06-01

    Even small degrees of residual neuromuscular blockade, i. e. a train-of-four (TOF) ratio >0.6, may lead to clinically relevant consequences for the patient. Especially upper airway integrity and the ability to swallow may still be markedly impaired. Moreover, increasing evidence suggests that residual neuromuscular blockade may affect postoperative outcome of patients. The incidence of these small degrees of residual blockade is relatively high and may persist for more than 90 min after a single intubating dose of an intermediately acting neuromuscular blocking agent, such as rocuronium and atracurium. Both neuromuscular monitoring and pharmacological reversal are key elements for the prevention of postoperative residual blockade.

  5. TENORM: Wastewater Treatment Residuals

    Science.gov (United States)

    Water and wastes which have been discharged into municipal sewers are treated at wastewater treatment plants. These may contain trace amounts of both man-made and naturally occurring radionuclides which can accumulate in the treatment plant and residuals.

  6. Measurement of inner wall limiter SOL widths in KSTAR tokamak

    Directory of Open Access Journals (Sweden)

    J.G. Bak

    2017-08-01

    Full Text Available Scrape-off layer (SOL widths λq are presented from the KSTAR tokamak using fast reciprocating Langmuir probe assembly (FRLPA measurements at the outboard mid-plane (OMP and the infra-Red (IR thermography at inboard limiter tiles in moderately elongated (κ = 1.45 – 1.55 L-mode inner wall-limited (IWL plasmas under experimental conditions such as BT = 2.0 T, PNBI = 1.4 – 1.5 MW, line averaged densities 2.5 – 5.1 × 1019 m−3 and plasma current Ip = 0.4 − 0.7 MA. There is clear evidence for a double exponential structure in q||(r from the FRLPA such that, for example at Ip = 0.6 MA, a narrow feature, λq,near (=3.5 mm is found close to the LFCS, followed by a broader width, λq,main (=57.0 mm. Double exponential profiles (λq,near = 1.5 – 2.8 mm, λq,main = 17.0 – 35.0 mm can be also observed in the IR heat flux mapped to the OMP throughout the range of Ip investigated. In addition, analysis of SOL turbulence statistics obtained with the FRLPA shows high relative fluctuation levels and positively skewed distributions in electron temperature and ion particle flux across the SOL, with both properties increasing for longer distance from the LCFS, as often previously observed in the tokamaks. Interestingly, the fluctuation character expressed in terms of spectral distributions remains unchanged in passing from the narrow to the broad SOL heat flux channel.

  7. Variable Width Riparian Model Enhances Landscape and Watershed Condition

    Science.gov (United States)

    Abood, S. A.; Spencer, L.

    2017-12-01

    Riparian areas are ecotones that represent about 1% of USFS administered landscape and contribute to numerous valuable ecosystem functions such as wildlife habitat, stream water quality and flows, bank stability and protection against erosion, and values related to diversity, aesthetics and recreation. Riparian zones capture the transitional area between terrestrial and aquatic ecosystems with specific vegetation and soil characteristics which provide critical values/functions and are very responsive to changes in land management activities and uses. Two staff areas at the US Forest Service have coordinated on a two phase project to support the National Forests in their planning revision efforts and to address rangeland riparian business needs at the Forest Plan and Allotment Management Plan levels. The first part of the project will include a national fine scale (USGS HUC-12 digits watersheds) inventory of riparian areas on National Forest Service lands in western United States with riparian land cover, utilizing GIS capabilities and open source geospatial data. The second part of the project will include the application of riparian land cover change and assessment based on selected indicators to assess and monitor riparian areas on annual/5-year cycle basis.This approach recognizes the dynamic and transitional nature of riparian areas by accounting for hydrologic, geomorphic and vegetation data as inputs into the delineation process. The results suggest that incorporating functional variable width riparian mapping within watershed management planning can improve riparian protection and restoration. The application of Riparian Buffer Delineation Model (RBDM) approach can provide the agency Watershed Condition Framework (WCF) with observed riparian area condition on an annual basis and on multiple scales. The use of this model to map moderate to low gradient systems of sufficient width in conjunction with an understanding of the influence of distinctive landscape

  8. Propagation effects on the Doppler frequency shift of satellite transmissions

    Science.gov (United States)

    Millman, G. H.; Arabadjis, M. C.

    1984-10-01

    The refraction phenomenon in the troposphere and the ionosphere causes an error in the Doppler frequency shift of radio transmissions emitted from a nonstationary satellite and received on the ground. Estimates are made of the Doppler error for various atmospheric and solar-geophysical conditions and are applicable for frequencies in the VHF to UHF range and above. The Doppler error imposed by the troposphere is directly proportional to frequency while, in the case of the ionosphere, the error is approximately inversely proportional to the frequency and approximately directly proportional to the vertical electron content. Under average tropospheric conditions, the tropospheric contribution to the Doppler error is predominant for frequencies on the order of 400 MHz and above. Below about 400 MHz, the ionospheric refraction effects are prevalent. The Doppler effects can be compensated for, to some extent, when the angular bending and the space vehicle velocity are known. Estimates of the angular bending due to the troposphere can be made to a fair degree of accuracy, from measurements of the surface refractivity. For the ionosphere, the vertical electron content data can be used for the estimation of the refraction angle error.

  9. Precise Doppler shift compensation in the hipposiderid bat, Hipposideros armiger.

    Science.gov (United States)

    Schoeppler, Diana; Schnitzler, Hans-Ulrich; Denzinger, Annette

    2018-03-15

    Bats of the Rhinolophidae and Hipposideridae families, and Pteronotus parnellii, compensate for Doppler shifts generated by their own flight movement. They adjust their call frequency such that the frequency of echoes coming from ahead fall in a specialized frequency range of the hearing system, the auditory fovea, to evaluate amplitude and frequency modulations in echoes from fluttering prey. Some studies in hipposiderids have suggested a less sophisticated or incomplete Doppler shift compensation. To investigate the precision of Doppler shift compensation in Hipposideros armiger, we recorded the echolocation and flight behaviour of bats flying to a grid, reconstructed the flight path, measured the flight speed, calculated the echo frequency, and compared it with the resting frequency prior to each flight. Within each flight, the average echo frequency was kept constant with a standard deviation of 110 Hz, independent of the flight speed. The resting and reference frequency were coupled with an offset of 80 Hz; however, they varied slightly from flight to flight. The precision of Doppler shift compensation and the offset were similar to that seen in Rhinolophidae and P. parnellii. The described frequency variations may explain why it has been assumed that Doppler shift compensation in hipposiderids is incomplete.

  10. New clutter-rejection algorithm for Doppler ultrasound

    Science.gov (United States)

    Cloutier, Guy; Chen, Danmin; Durand, Louis-Gilles

    2002-04-01

    Several strategies, known as clutter or wall Doppler filtering, were proposed to remove the strong echoes produced by stationary or slow moving tissue structures from the Doppler blood flow signal. In this study, the matching pursuit (MP) method is proposed to remove clutter components. The MP method decomposes the Doppler signal into wavelet atoms that are selected in a decreasing energy order. Thus, the high-energy clutter components are extracted first. In the present study, the pulsatile Doppler signal s(n) was simulated by a sum of random-phase sinusoids. Two types of high-amplitude clutter signals were then superimposed on s(n): a time-varying low frequency component (type 1), covering systole and early diastole, and short transient clutter signals (type 2), distributed within the whole cardiac cycle. The Doppler signals were modeled with the MP method and the most dominant atoms were subtracted until the signal-to-clutter (S/C) ratio reached a maximum. For the type 1 clutter signal, the improvement in the S/C ratio was 19.0 +/- 0.6 dB, and 72.0 +/- 4.5 atoms were required to reach this performance. For the transient type 2 clutter signal, exactly 10 atoms were required and the maximum improvement in S/C ratio was 5.5 +/- 0.5 dB. These results suggest the possibility of using this signal processing approach to implement clutter rejection filters on ultrasound commercial instruments.

  11. Color Doppler US in the acute scrotal disease

    International Nuclear Information System (INIS)

    Cha, Yoo Mi; Yang, Dal Mo; Kang, Sook Wook; Kim, Hyung Sik; Lee, Young Seok; Kim, Hyeon Hoe

    1993-01-01

    To evaluate the utility of Color doppler US in the patients with acute scrotal pain, we retrospectively analyzed 37 patients referred for Color Doppler US of the scrotum. The diagnosis was confirmed by means of appropriate response to antibiotic treatment (31 cases) or surgery (6 cases). Thirty one of 37 patients were diagnosed as inflammatory disease (24 cases of epididymitis, 7 cases of epididymo-orchitis). Twenty three of 24cases of epididymitis had increased epididymal flow, while 6 of 7 cases of epididymo-orchitis had increased epididymal and testicular flow. Five patients were confirmed as testicular torsion, and in all cases nointratesticular blood flow was identified on the symptomatic side. In one case of torsion of appendix testis, epididymis was enlarged and there were increased signals suggesting epididymitis on Color Doppler US, but was confirmed by surgery as torsion of appendix testis. Therefore, the differentiation between torsion and inflammatory disease was possible by using Color Doppler US of the scrotum in 34 of 37 cases in our study. On the basis of our results, we may conclude that Color Doppler US can simultaneously display blood flow and detailed anatomic images, and function as an effective means of evaluating patients with acute scrotal disease

  12. High-resolution Doppler model of the human gait

    Science.gov (United States)

    Geisheimer, Jonathan L.; Greneker, Eugene F., III; Marshall, William S.

    2002-07-01

    A high resolution Doppler model of the walking human was developed for analyzing the continuous wave (CW) radar gait signature. Data for twenty subjects were collected simultaneously using an infrared motion capture system along with a two channel 10.525 GHz CW radar. The motion capture system recorded three-dimensional coordinates of infrared markers placed on the body. These body marker coordinates were used as inputs to create the theoretical Doppler output using a model constructed in MATLAB. The outputs of the model are the simulated Doppler signals due to each of the major limbs and the thorax. An estimated radar cross section for each part of the body was assigned using the Lund & Browder chart of estimated body surface area. The resultant Doppler model was then compared with the actual recorded Doppler gait signature in the frequency domain using the spectrogram. Comparison of the two sets of data has revealed several identifiable biomechanical features in the radar gait signature due to leg and body motion. The result of the research shows that a wealth of information can be unlocked from the radar gait signature, which may be useful in security and biometric applications.

  13. Doppler sonographic assessment of posttraumatic reflex sympathetic dystrophy.

    Science.gov (United States)

    Pekindil, Gökhan; Pekindil, Yesim; Sarikaya, Ali

    2003-04-01

    To reveal the arterial Doppler sonographic findings in cases of posttraumatic reflex sympathetic dystrophy Eleven patients had hand reflex sympathetic dystrophy, and 9 had foot reflex sympathetic dystrophy. The duration of symptoms ranged from 1 to 28 weeks, and the history of fracture ranged from 6 to 48 weeks. Bilateral brachial or popliteal arteries proximal to injuries were evaluated by Doppler sonography with a 7.5-MHz linear transducer. All patients also had triphasic bone scintigraphy and extremity thermography Two patients had monophasic waveforms and 4 had low-pulsatility triphasic waveforms on the affected limbs when compared with the asymptomatic limbs. All opposite asymptomatic limbs had normal triphasic waveforms in these 6 cases. Spectral analysis revealed a loss or decrease of a normal reversed flow component with a reduced pulsatility index on the affected limb. Fourteen other patients had symmetric triphasic waveforms. We observed that the patients who had stage 1 reflex sympathetic dystrophy and warm limbs with durations of symptoms of more than 2 weeks had positive Doppler sonographic findings, whereas all patients with stage 2 reflex sympathetic dystrophy and all with normal skin temperature, regardless of stage, had normal waveforms. Doppler sonography revealed loss of normal triphasic arterial waveforms in some of the cases of stage 1 disease, whereas many cases of stage 1 disease and all cases of stage 2 disease had normal findings. Therefore, we think that Doppler sonography cannot be used for the diagnosis of reflex sympathetic dystrophy but may help in assessing hemodynamic stages of the disease.

  14. Temporal enhancement of two-dimensional color doppler echocardiography

    Science.gov (United States)

    Terentjev, Alexey B.; Settlemier, Scott H.; Perrin, Douglas P.; del Nido, Pedro J.; Shturts, Igor V.; Vasilyev, Nikolay V.

    2016-03-01

    Two-dimensional color Doppler echocardiography is widely used for assessing blood flow inside the heart and blood vessels. Currently, frame acquisition time for this method varies from tens to hundreds of milliseconds, depending on Doppler sector parameters. This leads to low frame rates of resulting video sequences equal to tens of Hz, which is insufficient for some diagnostic purposes, especially in pediatrics. In this paper, we present a new approach for reconstruction of 2D color Doppler cardiac images, which results in the frame rate being increased to hundreds of Hz. This approach relies on a modified method of frame reordering originally applied to real-time 3D echocardiography. There are no previous publications describing application of this method to 2D Color Doppler data. The approach has been tested on several in-vivo cardiac 2D color Doppler datasets with approximate duration of 30 sec and native frame rate of 15 Hz. The resulting image sequences had equivalent frame rates to 500Hz.

  15. Acute intrascrotal pathology in childhood: color Doppler study

    International Nuclear Information System (INIS)

    Cinta Sanguesa, C.; Muro, D.; Cortina, H.; Moreno, A.

    1997-01-01

    To asses the utility of color Doppler ultrasound in the study of acute intrascrotal pathology in childhood. Seventy-five boys with evidence of an acute intrascrotal abnormality were studied by means of color Doppler ultrasound. A 7.5 MHz linear transducer was used. The most common findings was inflammatory disease (60%) which was indicated by the presence of hyperemia in color Doppler. Of the nine boys with testicular torsion (12%) two presented extravaginal torsion, with a complete absence of intratesticular vascularization. Intravaginal torsion was observed in seven patients, six of whom presented reduced vascularization in the abnormal testicle with respect to the healthy testicle. There was one false negative in which testicular vascularization was normal but 360 degree centigree torsion was found at surgery. In addition, there were seven cases of hydatid torsion (9.33%), four of idiopathic scrotal swelling (5.3%). two cases of intermittent torsion (2.6%) and one case of Shcolein-Henoch purpura (1.3%). The ultrasound findings were completely nornal in seven boys. Color Doppler is a rapid, noninvasive method for assessing testicular blood flow. The elevated sensitivity and specificity (85.7 and 100%, respectively, in our series) for testicular torsion make Doppler ultrasound a highly reliable method for the study of this disorder. (Author) 18 refs

  16. Renal Power Doppler Ultrasonographic Evaluation of Children With Acute Pyelonephritis

    Directory of Open Access Journals (Sweden)

    Ali Pahlusi

    2011-10-01

    Full Text Available Urinary tract infections are common in children. The available gold standard method for diagnosis, Tc-99m dimercaptosuccinic acid scan is expensive and exposes patients to considerable amount of radiation. This study was performed to compare and assess the efficacy of Power Doppler Ultrasound versus Tc-99m DMSA scan for diagnosis of acute pyelonephritis. A quasi experimental study was conducted on 34 children with mean age of 2.82.7 years who were hospitalized with their first episode of febrile urinary tract infection. All children were evaluated in the first 3 days of admission by Doppler Ultrasound and Tc-99m DMSA scan. Patients with congenital structural anomalies were excluded. Each kidney was divided into three zones. The comparison between efficacy of Doppler Ultrasound and DMSA scan was carried out based on number of patients and on classified renal units. Based on the number of patients enrolled; the sensitivity, specificity, positive and negative predictive values and accuracy of Doppler Ultrasound were 89%, 53%, 70%, 80% and 74%, respectively but based on the renal units, it was 66%, 81%, 46%, 91% and 79% , respectively. Although Doppler Ultrasound has the potential for identifying acute pyelonephritis in children, but it is still soon to replace DMSA scan.

  17. Residuation in orthomodular lattices

    Directory of Open Access Journals (Sweden)

    Chajda Ivan

    2017-04-01

    Full Text Available We show that every idempotent weakly divisible residuated lattice satisfying the double negation law can be transformed into an orthomodular lattice. The converse holds if adjointness is replaced by conditional adjointness. Moreover, we show that every positive right residuated lattice satisfying the double negation law and two further simple identities can be converted into an orthomodular lattice. In this case, also the converse statement is true and the corresponence is nearly one-to-one.

  18. Ecocardiografia modo Doppler pulsado em gatos clinicamente sadios Pulsed wave Doppler echocardiography in clinically healthy cats

    OpenAIRE

    R.O. Carvalho; R.B. Araújo; E.F. Silva

    2006-01-01

    Estudou-se o fluxo sangüíneo através das quatro valvas cardíacas em 30 gatos clinicamente sadios, com idade entre um e cinco anos e peso médio de 4,08kg, por meio da ecocardiografia modo Doppler pulsado. Foram medidas a velocidade máxima e a velocidade média dos fluxos, e realizou-se uma análise qualitativa dos seus perfis. Os animais foram sedados pela combinação de quetamina (12mg/kg) e acepromazina (0,04mg/kg), aplicados por via intramuscular. Observou-se correlação positiva entre os parâm...

  19. Characterization of Hospital Residuals

    International Nuclear Information System (INIS)

    Blanco Meza, A.; Bonilla Jimenez, S.

    1997-01-01

    The main objective of this investigation is the characterization of the solid residuals. A description of the handling of the liquid and gassy waste generated in hospitals is also given, identifying the source where they originate. To achieve the proposed objective the work was divided in three stages: The first one was the planning and the coordination with each hospital center, in this way, to determine the schedule of gathering of the waste can be possible. In the second stage a fieldwork was made; it consisted in gathering the quantitative and qualitative information of the general state of the handling of residuals. In the third and last stage, the information previously obtained was organized to express the results as the production rate per day by bed, generation of solid residuals for sampled services, type of solid residuals and density of the same ones. With the obtained results, approaches are settled down to either determine design parameters for final disposition whether for incineration, trituration, sanitary filler or recycling of some materials, and storage politics of the solid residuals that allow to determine the gathering frequency. The study concludes that it is necessary to improve the conditions of the residuals handling in some aspects, to provide the cleaning personnel of the equipment for gathering disposition and of security, minimum to carry out this work efficiently, and to maintain a control of all the dangerous waste, like sharp or polluted materials. In this way, an appreciable reduction is guaranteed in the impact on the atmosphere. (Author) [es

  20. Ecocardiografia modo Doppler pulsado em gatos clinicamente sadios Pulsed wave Doppler echocardiography in clinically healthy cats

    Directory of Open Access Journals (Sweden)

    R.O. Carvalho

    2006-06-01

    Full Text Available Estudou-se o fluxo sangüíneo através das quatro valvas cardíacas em 30 gatos clinicamente sadios, com idade entre um e cinco anos e peso médio de 4,08kg, por meio da ecocardiografia modo Doppler pulsado. Foram medidas a velocidade máxima e a velocidade média dos fluxos, e realizou-se uma análise qualitativa dos seus perfis. Os animais foram sedados pela combinação de quetamina (12mg/kg e acepromazina (0,04mg/kg, aplicados por via intramuscular. Observou-se correlação positiva entre os parâmetros avaliados e a freqüência cardíaca, com exceção daqueles medidos no fluxo da valva aórtica. Não se observou correlação entre velocidades máxima e média e freqüência cardíaca e entre aquelas e peso corporal, e não houve diferença entre sexos.Pulsed wave Doppler echocardiography was used to study blood flow across the cardiac valves in 30 five-year-old cats (average body weight = 4.08kg. Animals were sedated using a combination of ketamin (12mg/kg, IM and acepromazin (0.04mg/kg, IM. Peak and mean velocities were determined, and blood flow patterns were recorded at the four cardiac valves. All variables, except those characterizing aortic valve flow, were positively correlated with heart rate. Blood flow variables were not correlated, however, with body weight; and there were no differences between males and females.

  1. Influence of pulse width in laser assisted texturing on moly-chrome films

    Science.gov (United States)

    Ezhilmaran, V.; Vijayaraghavan, L.; Vasa, N. J.; Krishnan, Sivarama

    2018-02-01

    Continuous micro-channels were formed on the surface of the automotive piston rings using two different lasers, namely nanosecond and femtosecond pulsed laser. Tribology measurements were conducted to compare the friction properties of the samples fabricated with the laser pulse width of nanosecond and femtosecond order. The femtosecond laser ablation comparatively minimized the re-deposition layer, heat affected zone around the micro-channel compared to the nanosecond laser ablation. Owing to the localized material ablation, the compressive residual stress was not altered with femtosecond laser processing. The friction test was conducted using reciprocating type friction measurement setup for the loads ranging from 10 to 130 N. The friction coefficients of all the textured samples were reduced compared to the non-textured samples. Furthermore, it is observed that the average friction coefficient was low with the femtosecond laser textured samples compared to that of the nanosecond laser textured samples of the same dimensions. The results show that the thermally induced defects while using the nanosecond laser ablation might have influenced the tribological properties.

  2. Traffic pollution affects tree-ring width and isotopic composition of Pinus pinea

    International Nuclear Information System (INIS)

    Battipaglia, Giovanna; Marzaioli, Fabio; Lubritto, Carmine; Altieri, Simona; Strumia, Sandro; Cherubini, Paolo; Cotrufo, M. Francesca

    2010-01-01

    This study presents new evidence that radiocarbon, combined with dendrochronological and stable isotopes analysis in tree rings and needles, can help to better understand the influence of pollution on trees. Pinus pinea individuals, adjacent to main roads in the urban area of Caserta (South Italy) and exposed to large amounts of traffic exhaust since 1980, were sampled and the time-related trend in the growth residuals was estimated. We found a consistent decrease in the ring width starting from 1980, with a slight increase in δ 13 C value, which was considered to be a consequence of environmental stress. No clear pattern was identified in δ 15 N, while an increasing effect of the fossil fuel dilution on the atmospheric bomb-enriched 14 C background was detected in tree rings, possibly as a consequence of the increase in traffic exhausts. Our findings suggested that radiocarbon is a very sensitive tool to investigate small-scale (i.e. traffic exhaust at the level crossing) and large-scale (urban area pollution) induced disturbances.

  3. Lorentz invariance and the rotor Doppler shift experiments

    International Nuclear Information System (INIS)

    Rodrigues Junior, W.A.; Tiomno, J.

    1984-01-01

    It is shown that 'Rotor Doppler shift Experiments' provide a way to distinguish Einstein's Special Relativity (SR) from Lorentz's Aether Theory (LAT). Misconceptions in previous papers involving the Doppler shift experiments are examined. The theoretical and experimental data available on rotor Doppler shift experiments are analysed. Two models of SR violating theories are used to predict the output of a recently proposed experiment by Torr and Kolen. The first one corresponds to (strict) LAT and the other to an extended form of LAT Contrary to the first, the second theory leads to results in agreement with the preliminary experimental data of Torr et al indicating a breakdown both of SR and strict LAT. (Author) [pt

  4. Moving Target Detection With Compact Laser Doppler Radar

    Science.gov (United States)

    Sepp, G.; Breining, A.; Eisfeld, W.; Knopp, R.; Lill, E.; Wagner, D.

    1989-12-01

    This paper describes an experimental integrated optronic system for detection and tracking of moving objects. The system is based on a CO2 waveguide laser Doppler ra-dar with homodyne receiver and galvanometer mirror beam scanner. A "hot spot" seeker consisting of a thermal imager with image processor transmits the coordinates of IR-emitting, i.e. potentially powered, objects to the laser radar scanner. The scanner addresses these "hot" locations operating in a large field-of-view (FOV) random ac-cess mode. Hot spots exhibiting a Doppler shifted laser signal are indicated in the thermal image by velocity-to-colour encoded markers. After switching to a small FOV scanning mode, the laser Doppler radar is used to track fast moving objects. Labora-tory and field experiments with moving objects including rotating discs, automobiles and missiles are described.

  5. Assessment of right ventricular systolic function by tissue Doppler echocardiography

    DEFF Research Database (Denmark)

    Kjærgaard, Jesper

    2012-01-01

    This thesis summarizes a series of studies performed in order to assess the clinical usefulness of a novel echocardiographic technology that allows non-invasive assessment of regional right ventricular myocardial velocities and deformation: tissue Doppler echocardiography. While the technology...... and pharmacological pulmonary vasodilatation is established in normal subjects. The diagnostic and prognostic importance of adding tissue Doppler echocardiography to conventional echocardiographic and clinical parameters was evaluated in studies on patients with diseases associated with different modes of impact...... on right ventricular hemodynamics: pulmonary embolism, Arrhythmogenic right ventricular cardiomyopathy and pulmonary regurgitation, the latter in an animal model. The conclusions of the thesis are: Color tissue Doppler echocardiography accurately measures velocities, SR and strain in vitro. No systematic...

  6. 3D atom microscopy in the presence of Doppler shift

    Science.gov (United States)

    Rahmatullah; Chuang, You-Lin; Lee, Ray-Kuang; Qamar, Sajid

    2018-03-01

    The interaction of hot atoms with laser fields produces a Doppler shift, which can severely affect the precise spatial measurement of an atom. We suggest an experimentally realizable scheme to address this issue in the three-dimensional position measurement of a single atom in vapors of rubidium atoms. A three-level Λ-type atom–field configuration is considered where a moving atom interacts with three orthogonal standing-wave laser fields and spatial information of the atom in 3D space is obtained via an upper-level population using a weak probe laser field. The atom moves with velocity v along the probe laser field, and due to the Doppler broadening the precision of the spatial information deteriorates significantly. It is found that via a microwave field, precision in the position measurement of a single hot rubidium atom can be attained, overcoming the limitation posed by the Doppler shift.

  7. Venstre ventrikels diastoliske funktion vurderet med transtorakal Doppler-ekkokardiografi

    DEFF Research Database (Denmark)

    Poulsen, S H; Jensen, S E; Gøtzsche, O

    1996-01-01

    Left ventricular diastolic dysfunction is currently recognized in patients with different heart diseases. Three abnormal filling patterns of the left ventricle detected by pulsed-Doppler echocardiography are observed in patients with heart disease. Each filling pattern is characterised by different...... symptoms, and by differences in function and dimension of the left atrium and filling pressures. Mitral and pulmonary venous flow velocities and durations obtained by pulsed Doppler technique can be used to evaluate left ventricular diastolic function in patients with different heart diseases. However......, several factors affect the transmitral and pulmonary venous flow such as age, heart rate, positioning of the sample volume and aortic- and mitral valve insufficiency. These factors must be taken into consideration when the diastolic function is evaluated by pulsed Doppler technique....

  8. Classification of transcranial Doppler signals using artificial neural network.

    Science.gov (United States)

    Serhatlioğlu, Selami; Hardalaç, Firat; Güler, Inan

    2003-04-01

    Transcranial Doppler signals, recorded from the temporal region of brain on 110 patients were transferred to a personal computer by using a 16-bit sound card. The fast Fourier transform (FFT) method was applied to the recorded signal from each patient. Since FFT method inherently can not offer a good spectral resolution at jet blood flows, it sometimes causes wrong interpretation of transcranial Doppler signals. To do a correct and rapid diagnosis, transcranial Doppler blood flow signals were statistically arranged so that they were classified in artificial neural network. Back propagation neural network and self-organization map algorithms of artificial neural network were used for training, whereas momentum and delta-bar-delta algorithms were used for learning. The results of these algorithms were compared in the case of classification and learning.

  9. Pulsed and Color Doppler Sonographic Findings of Penile Mondor' Disease

    International Nuclear Information System (INIS)

    Han, Hye Yeon; Chung, Dong Jin; Kim, Kum Won; Hwang, Cheol Mog

    2008-01-01

    Penile Mondor's disease is a rare disease that's characterized by thrombosis in the dorsal vein of the penis. Doppler ultrasonography (US) clearly visualizes dorsal vein thrombosis and the associated hemodynamic alterations. Previous studies have demonstrated the typical color Doppler US findings of superficial dorsal vein thrombosis without the flow signals in this area, yet this is insufficient to understand the hemodynamics in penile Mondor's disease. We report here for the first time a cavernosal artery flow signal pattern in a penile Mondor's disease patient, in addition to its previously reported classic US findings. In conclusion, the Doppler US findings of thrombus without blood flow in the superficial dorsal vein and the low-flow, high resistance in the cavernosal artery may be suggestive of penile Mondor's disease

  10. Determination of intestinal viability by Doppler ultrasonography in venous infarction.

    Science.gov (United States)

    Cooperman, M; Martin, E W; Carey, L C

    1980-01-01

    The accuracy of Doppler ultrasound in predicting the viability of ischemic intestine secondary to venous obstruction was assessed. Twenty loops of ischemic intestine were created in dogs by temporarily obstructing venous return from the bowel. Doppler arterial flow signals within the intestine quickly disappeared following venous occlusion. In ten segments, arterial signals promptly returned following release of venous occlusion. Nine of these ten segments were viable at reoperation 24 hours later. In ten segments, no arterial signals could be detected following release of venous occlusion, and only one segment proved to be viable. Doppler ultrasound findings were far more accurate in distinguishing between viable and nonviable intestine thatn were clinical guides to intestinal viability. PMID:7352777

  11. The Doppler paradigm and the APEX-EPOS-ORANGE quandary

    International Nuclear Information System (INIS)

    Griffin, J.J.

    1995-01-01

    The experimental detection of the sharp lines of the (e + e - ) Puzzle is viewed as a struggle against Doppler broadening. Gedanken experiments which are realistic in zeroth order of detail are analyzed to show that the ORANGE and EPOS/I geometries select narrower slices of a Doppler broadened line than spherically inclusive (APEX and EPOS/II -like) apparati. Roughly speaking, the latter require event-by-event Doppler reconstruction simply to regain an even footing with the former. This suggests that APEX' or EPOS/II's coincident pair distributions must be statistically superior to those of EPOS/I or ORANGE in order to support a comparable inference about sharp structure. Under such circumstances, independent alternative data is invaluable. Therefore, a corroboration of Sakai's 330.1 keV ( + or e - bombardments of U and Th targets could prove crucial

  12. Doppler term in the galaxy two-point correlation function: Wide-angle, velocity, Doppler lensing and cosmic acceleration effects

    Science.gov (United States)

    Raccanelli, Alvise; Bertacca, Daniele; Jeong, Donghui; Neyrinck, Mark C.; Szalay, Alexander S.

    2018-03-01

    We study the parity-odd part (that we shall call Doppler term) of the linear galaxy two-point correlation function that arises from wide-angle, velocity, Doppler lensing and cosmic acceleration effects. As it is important at low redshift and at large angular separations, the Doppler term is usually neglected in the current generation of galaxy surveys. For future wide-angle galaxy surveys, however, we show that the Doppler term must be included. The effect of these terms is dominated by the magnification due to relativistic aberration effects and the slope of the galaxy redshift distribution and it generally mimics the effect of the local type primordial non-Gaussianity with the effective nonlinearity parameter fNLeff of a few; we show that this would affect forecasts on measurements of fNL at low-redshift. Our results show that a survey at low redshift with large number density over a wide area of the sky could detect the Doppler term with a signal-to-noise ratio of ∼ 1 - 20, depending on survey specifications.

  13. Diagnostic value of appendicular Doppler ultrasonography in acute appendicitis.

    Science.gov (United States)

    Uzunosmanoğlu, Hüseyin; Çevik, Yunsur; Çorbacıoğlu, Şeref Kerem; Akıncı, Emine; Buluş, Hakan; Ağladıoğlu, Kadir

    2017-05-01

    Acute appendicitis is one of the most common causes of acute abdominal pain prompting emergency department (ED) visits. It is critical for the physicians to promptly and accurately diagnose acute appendicitis. The present study aimed to evaluate the diagnostic efficacy of Doppler ultrasonography (USG) in patients with acute appendicitis and compare this new method with other commonly used radio-diagnostic tools. All patients who were diagnosed with acute appendicitis at the Kecioren Training and Research Hospital ED and later underwent appendectomy between October 2012 and April 2013 were included in the study. Approval from the ethics committee was obtained for this prospective study. The patients' demographic information, physical examination findings, vital signs, Alvarado scores, and laboratory and radiological exam results were recorded. A total of 60 patients were enrolled in the study. In 46 of the 60 patients, diagnosis of acute appendicitis was confirmed by histopathology results, whereas 14 patients, diagnoses was not confirmed by lab tests. Doppler USG could detect 43 of the 46 patients as true positives, and it detected 2 of the 14 patients with negative lab results as false positives. For diagnosis of acute appendicitis, sensitivity of appendicular Doppler USG was 93%, specificity was 85%, accuracy was 91%, positive likelihood ratio was 6.5, and negative likelihood ratio was 0.08. Doppler imaging can offer a high level of diagnostic success in patients with acute appendicitis. Appendicular Doppler USG offers a rapid and easy application without the need to expose patients to contrast medium and is superior to both USG and computed tomography. Therefore, we recommend the use of appendicular Doppler imaging as the primary radiological exam in diagnosing acute appendicitis.

  14. Evaluation of postoperative pulmonary regurgitation after surgical repair of tetralogy of Fallot: comparison between Doppler echocardiography and MR velocity mapping

    Energy Technology Data Exchange (ETDEWEB)

    Grothoff, Matthias; Spors, Birgit; Gutberlet, Matthias [Charite Campus Virchow Klinikum, Department of Radiology and Nuclear Medicine, Berlin (Germany); Abdul-Khaliq, Hasim [Deutsches Herzzentrum, Department of Congenital Heart Disease/Pediatric Cardiology, Berlin (Germany)

    2008-02-15

    Pulmonary regurgitation is a common finding in patients after correction of tetralogy of Fallot (TOF). Right ventricular impairment and even ventricular arrhythmia have been ascribed to pulmonary valve insufficiency (PI), which is therefore an important issue in follow-up examinations. To compare PI measured by echocardiography (ECHO) with data provided by cardiac MRI (CMR). We studied 54 selected patients (18 female; median age 14.0 years, range 3.8-53.4 years) after surgical correction of TOF. To quantify pulmonary regurgitant fraction (PRF) by CMR, flow velocity mapping was performed. On Doppler ECHO, length, width and localization of regurgitant flow was measured. The severity of PI was categorized as mild, moderate or severe and compared to the data obtained by CMR. On CMR the mean PRF was 29.2 {+-} 13.4%. Patients with a transannular patch had a significantly higher PRF (39.9 {+-} 11.6%) than patients with an intact annular ring (23.6 {+-} 11.4%). Differentiation by Doppler ECHO between the categories mild, moderate and severe PI was confirmed by significant differences in PRF measured by CMR (mild vs. moderate P < 0.04; moderate vs. severe P < 0.014; mild vs. severe P < 0.001). Furthermore, PRF correlated with right ventricular end diastolic volume index (r = 0.45, P < 0.01) and right ventricular end systolic volume index (r = 0.39, P < 0.01). Doppler ECHO can estimate the severity of PI after repair of TOF with acceptable results compared to CMR flow measurement. In univariate analysis there is only a weak influence of PRF on right ventricular volume. (orig.)

  15. Evaluation of postoperative pulmonary regurgitation after surgical repair of tetralogy of Fallot: comparison between Doppler echocardiography and MR velocity mapping

    International Nuclear Information System (INIS)

    Grothoff, Matthias; Spors, Birgit; Gutberlet, Matthias; Abdul-Khaliq, Hasim

    2008-01-01

    Pulmonary regurgitation is a common finding in patients after correction of tetralogy of Fallot (TOF). Right ventricular impairment and even ventricular arrhythmia have been ascribed to pulmonary valve insufficiency (PI), which is therefore an important issue in follow-up examinations. To compare PI measured by echocardiography (ECHO) with data provided by cardiac MRI (CMR). We studied 54 selected patients (18 female; median age 14.0 years, range 3.8-53.4 years) after surgical correction of TOF. To quantify pulmonary regurgitant fraction (PRF) by CMR, flow velocity mapping was performed. On Doppler ECHO, length, width and localization of regurgitant flow was measured. The severity of PI was categorized as mild, moderate or severe and compared to the data obtained by CMR. On CMR the mean PRF was 29.2 ± 13.4%. Patients with a transannular patch had a significantly higher PRF (39.9 ± 11.6%) than patients with an intact annular ring (23.6 ± 11.4%). Differentiation by Doppler ECHO between the categories mild, moderate and severe PI was confirmed by significant differences in PRF measured by CMR (mild vs. moderate P < 0.04; moderate vs. severe P < 0.014; mild vs. severe P < 0.001). Furthermore, PRF correlated with right ventricular end diastolic volume index (r = 0.45, P < 0.01) and right ventricular end systolic volume index (r = 0.39, P < 0.01). Doppler ECHO can estimate the severity of PI after repair of TOF with acceptable results compared to CMR flow measurement. In univariate analysis there is only a weak influence of PRF on right ventricular volume. (orig.)

  16. Spectral Doppler ultrasound of peripheral arteries: a pictorial review.

    Science.gov (United States)

    Nuffer, Zachary; Rupasov, Andrey; Bekal, Neel; Murtha, Jacqueline; Bhatt, Shweta

    This article reviews the pathophysiology and sonographic findings of peripheral arterial lesions, with emphasis on the spectral Doppler waveforms encountered in each. It discusses the characteristic features of the Doppler spectra in obstructive conditions, including thromboembolism, atherosclerotic disease, bypass graft occlusion, dissection, trauma, and compartment syndrome, as well as non-obstructive conditions, including hyperemia, pseudoaneurysm, and arteriovenous fistula. Familiarity with the commonly-encountered spectral waveforms in the setting of these lesions is necessary for timely and accurate diagnosis and treatment. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. Imaging doppler lidar for wind turbine wake profiling

    Science.gov (United States)

    Bossert, David J.

    2015-11-19

    An imaging Doppler lidar (IDL) enables the measurement of the velocity distribution of a large volume, in parallel, and at high spatial resolution in the wake of a wind turbine. Because the IDL is non-scanning, it can be orders of magnitude faster than conventional coherent lidar approaches. Scattering can be obtained from naturally occurring aerosol particles. Furthermore, the wind velocity can be measured directly from Doppler shifts of the laser light, so the measurement can be accomplished at large standoff and at wide fields-of-view.

  18. Spectral fine structure effects on material and doppler reactivity worth

    International Nuclear Information System (INIS)

    Greenspan, E.; Karni, Y.

    1975-01-01

    New formulations concerning the fine structure effects on the reactivity worth of resonances are developed and conclusions are derived following the extension to more general types of perturbations which include: the removal of resonance material at finite temperatures and the temperature variation of part of the resonance material. It is concluded that the flux method can overpredict the reactivity worth of resonance materials more than anticipated. Calculations on the Doppler worth were carried out; the results can be useful for asessing the contribution of the fine structure effects to the large discrepancy that exists between the calculated and measured small sample Doppler worths. (B.G.)

  19. Prenatal color Doppler ultrasonographic diagnosis of fetal tetralogy of Fallot

    International Nuclear Information System (INIS)

    Tan Buqiao

    2009-01-01

    Objective: To investigate the sonographic findings of tetralogy of Fallot in fetuses. Methods: The data of color Doppler ultrasonography and follow-up results of 5 fetal tetralogy of Fallot were analyzed retrospectively, and their abnormal ultrasound imaging characteristic were summarized. Results: Two cases were proved tetralogy of Fallot by autopsy, and three cases were confirmed to be tetralogy of Fallot by echocardiography after birth. The image features were the main aorta situated above the ventricular septal defect, pulmonary stenosis, no obvious thickening of the right wall. Conclusion: Fetal tetralogy of Fallot have characteristic ultrasound images, prenatal color Doppler ultrasonographic can diagnoses fetal tetralogy of Fallot correctly and has important clinical value. (authors)

  20. Aerial ultrasonic micro Doppler sonar detection range in outdoor environments.

    Science.gov (United States)

    Bradley, Marshall; Sabatier, James M

    2012-03-01

    Current research demonstrates that micro Doppler sonar has the capability to uniquely identify the presence of a moving human, making it an attractive component in surveillance systems for border security applications. Primary environmental factors that limit sonar performance are two-way spreading losses, ultrasonic absorption, and backscattered energy from the ground that appears at zero Doppler shift in the sonar signal processor. Spectral leakage from the backscatter component has a significant effect on sonar performance for slow moving targets. Sonar performance is shown to rapidly decay as the sensor is moved closer to the ground due to increasing surface backscatter levels. © 2012 Acoustical Society of America

  1. Cerebral ischemia: magnetic resonance angiography and transcranial Doppler evaluation.

    Science.gov (United States)

    D'Aprile, P; Federico, F; Medicamento, N; Conte, C; Carella, A

    1994-02-01

    We examined 21 patients with ischemic cerebrovascular disease using magnetic resonance angiography and transcranial Doppler. In 17 patients (81%), the results obtained by the two methods were concordant. In our opinion, the associated use of transcranial Doppler and magnetic resonance angiography provides an accurate diagnostic evaluation of ischemic stroke patients, not only allowing the site of possible steno-occlusive disease of large and medium cerebral vessels to be identified, but also offering the possibility of obtaining dynamic information concerning the direction of blood flow in the presence of compensatory circulations at the level of Willis' circle.

  2. Photodetachment and Doppler laser cooling of anionic molecules

    Science.gov (United States)

    Gerber, Sebastian; Fesel, Julian; Doser, Michael; Comparat, Daniel

    2018-02-01

    We propose to extend laser-cooling techniques, so far only achieved for neutral molecules, to molecular anions. A detailed computational study is performed for {{{C}}}2- molecules stored in Penning traps using GPU based Monte Carlo simulations. Two cooling schemes—Doppler laser cooling and photodetachment cooling—are investigated. The sympathetic cooling of antiprotons is studied for the Doppler cooling scheme, where it is shown that cooling of antiprotons to subKelvin temperatures could becomes feasible, with impacts on the field of antimatter physics. The presented cooling schemes also have applications for the generation of cold, negatively charged particle sources and for the sympathetic cooling of other molecular anions.

  3. UltraFast Doppler ultrasonography for hepatic vessels of liver recipients: preliminary experiences

    Energy Technology Data Exchange (ETDEWEB)

    Hur, Bo Yun; Lee, Jae Young; Chu, A Jung; Kim, Se Hyung; Han, Joon Koo; Choi, Byung Ihn [Seoul National University Hospital, Seoul (Korea, Republic of)

    2015-01-15

    The purpose of this study was to investigate the value of UltraFast Doppler ultrasonography (US) for evaluating hepatic vessels in liver recipients. Thirty-nine liver Doppler US sessions were conducted in 20 liver recipients. Each session consisted of UltraFast and conventional liver Doppler US in a random order. We compared the velocities and phasicities of the hepatic vessels, duration of each Doppler study, occurrence of technical failures, and differences in clinical decisions. The velocities and resistive index values of hepatic vessels showed a strong positive correlation between the two Doppler studies (mean R=0.806; range, 0.710 to 0.924). The phasicities of the hepatic vessels were the same in both Doppler US exams. With respect to the duration of the Doppler US exam, there was no significant difference between the UltraFast (251±99 seconds) and conventional (231±117 seconds) Doppler studies (P=0.306). In five poor breath-holders, in whom the duration of conventional Doppler US was longer, UltraFast Doppler US (272±157 seconds) required a shorter time than conventional Doppler US (381±133 seconds; P=0.005). There was no difference between the two techniques with respect to technical failures and clinical decisions. UltraFast Doppler US is clinically equivalent to conventional Doppler US with advantages for poor breath-holders during the post-liver transplantation work-up.

  4. First Metatarsal Head and Medial Eminence Widths with and Without Hallux Valgus.

    Science.gov (United States)

    Lenz, Robin C; Nagesh, Darshan; Park, Hannah K; Grady, John

    2016-09-02

    Resection of the medial eminence in hallux valgus surgery is common. True hypertrophy of the medial eminence in hallux valgus is debated. No studies have compared metatarsal head width in patients with hallux valgus and control patients. We reviewed 43 radiographs with hallux valgus and 27 without hallux valgus. We measured medial eminence width, first metatarsal head width, and first metatarsal shaft width in patients with and without radiographic hallux valgus. Medial eminence width was 1.12 mm larger in patients with hallux valgus (P hallux valgus (P hallux valgus. However, frontal plane rotation of the first metatarsal likely accounts for this difference.

  5. Management of NORM Residues

    International Nuclear Information System (INIS)

    2013-06-01

    The IAEA attaches great importance to the dissemination of information that can assist Member States in the development, implementation, maintenance and continuous improvement of systems, programmes and activities that support the nuclear fuel cycle and nuclear applications, and that address the legacy of past practices and accidents. However, radioactive residues are found not only in nuclear fuel cycle activities, but also in a range of other industrial activities, including: - Mining and milling of metalliferous and non-metallic ores; - Production of non-nuclear fuels, including coal, oil and gas; - Extraction and purification of water (e.g. in the generation of geothermal energy, as drinking and industrial process water; in paper and pulp manufacturing processes); - Production of industrial minerals, including phosphate, clay and building materials; - Use of radionuclides, such as thorium, for properties other than their radioactivity. Naturally occurring radioactive material (NORM) may lead to exposures at some stage of these processes and in the use or reuse of products, residues or wastes. Several IAEA publications address NORM issues with a special focus on some of the more relevant industrial operations. This publication attempts to provide guidance on managing residues arising from different NORM type industries, and on pertinent residue management strategies and technologies, to help Member States gain perspectives on the management of NORM residues

  6. Maxillary arch width and buccal corridor changes with Damon and conventional brackets: A retrospective analysis.

    Science.gov (United States)

    Shook, Corey; Kim, Sohyon Michelle; Burnheimer, John

    2016-07-01

    To evaluate the effect of Damon self-ligating and conventional bracket systems on buccal corridor widths and areas. A retrospective sample of consecutively treated patients using either conventional (CG, n  =  45) or Damon self-ligating (SL, n  =  39) brackets was analyzed to determine any differences in buccal corridor widths and areas both within and between groups. Pretreatment and posttreatment frontal photographs were transferred to Photoshop CC, standardized using intercanthal width, and linear and area measurements were performed with tools in Photoshop CC. Ratios were then calculated for statistical analysis. Relationships between arch widths and buccal corridors were also examined. There were no significant differences in the posttreatment intercanine or intermolar widths either within or between the CG and SL groups. There were no significant differences in any buccal corridor width or area measurement either within or between the CG and SL groups. There were strong correlations with the intercanine width and the corresponding buccal corridor smile width measurements. There was an inverse correlation with the buccal corridor area in relation to the canine and the total smile width. It is likely that posttreatment increases in arch width can be seen in patients treated with either a conventional bracket system or the Damon system. It is highly unlikely that there is any significant difference in buccal corridor width or area in patients treated with the Damon self-ligating system or a conventional bracket system.

  7. [Quantitative Analysis of Power Doppler Images in Lateral Humeral Enthesopathy].

    Science.gov (United States)

    Walder, P; Paša, L; Pavliska, L

    2016-01-01

    PURPOSE OF THE STUDY The evaluation of efficiency of power Doppler sonography in the diagnosis of lateral humeral enthesopathy, role of correct assessment of Doppler sonographic images with the method of quantitative analysis, assessment of statistical differences between a group of patients with lateral humeral enthesopathy and a control group of healthy subjects and assessment of the diagnostic power of this test. In addition, consideration of the relevance of each area of the lateral compartment for assessment and diagnosis making in lateral humeral enthesopathy. MATERIAL AND METHODS A total of 41 subjects, aged 18 to 60 years, entered the study. Thirteen patients were diagnosed with lateral humeral enthesopathy on the basis of clinical tests and a positive reaction of the lateral humeral epicondylus to administration of local anaesthetic. The control group consisted of 28 subjects without clinical signs of lateral humeral enthesopathy and subjective complaints. Power Doppler activity was evaluated in the whole region studied and in sub-regions involving the enthesis of the common extensor tendon and the periosteum of the lateral epicondyle with the area distal to it. The evaluation was based on calculating the overall surface with power Doppler activity using the method of quantitative image analysis. Each patient was measured on three occasions and the median of values obtained was used in calculation. To assess the diagnostic power of this test, all values obtained from the whole power Doppler region measured were used. The optimal dividing criterion at which the method had a maximum of sensitivity and specificity was determined. RESULTS The most evident, statistically significant difference between the patient and the control group was recorded in the whole "Range of Interest" (ROI) region (p=1.34x10-6). A significant difference was also found in sub-regions corresponding chiefly to the tendon of the extensor carpi radialis brevis muscle and to the

  8. Width of gene expression profile drives alternative splicing.

    Directory of Open Access Journals (Sweden)

    Daniel Wegmann

    Full Text Available Alternative splicing generates an enormous amount of functional and proteomic diversity in metazoan organisms. This process is probably central to the macromolecular and cellular complexity of higher eukaryotes. While most studies have focused on the molecular mechanism triggering and controlling alternative splicing, as well as on its incidence in different species, its maintenance and evolution within populations has been little investigated. Here, we propose to address these questions by comparing the structural characteristics as well as the functional and transcriptional profiles of genes with monomorphic or polymorphic splicing, referred to as MS and PS genes, respectively. We find that MS and PS genes differ particularly in the number of tissues and cell types where they are expressed.We find a striking deficit of PS genes on the sex chromosomes, particularly on the Y chromosome where it is shown not to be due to the observed lower breadth of expression of genes on that chromosome. The development of a simple model of evolution of cis-regulated alternative splicing leads to predictions in agreement with these observations. It further predicts the conditions for the emergence and the maintenance of cis-regulated alternative splicing, which are both favored by the tissue specific expression of splicing variants. We finally propose that the width of the gene expression profile is an essential factor for the acquisition of new transcript isoforms that could later be maintained by a new form of balancing selection.

  9. Blood and Wall Signal Simulator for Doppler Ultrasound Signal Analysis Algorithm Development

    National Research Council Canada - National Science Library

    Fish, P

    2001-01-01

    Doppler ultrasound instruments, used for the detection and monitoring of vascular disease, require a means of separating the large, low frequency Doppler signal from the vessel wall from the signal...

  10. GPM Ground Validation NASA S-Band Dual Polarimetric (NPOL) Doppler Radar OLYMPEX V2

    Data.gov (United States)

    National Aeronautics and Space Administration — The GPM Ground Validation NASA S-Band Dual Polarimetric (NPOL) Doppler Radar OLYMPEX V2 dataset consists of rain rate, reflectivity, Doppler velocity, and other...

  11. Correlation between Doppler flow patterns in growth-restricted fetuses and neonatal circulation

    NARCIS (Netherlands)

    Tanis, J. C.; Boelen, M. R.; Schmitz, D. M.; Casarella, L.; van der Laan, M. E.; Bos, A. F.; Bilardo, C. M.

    Objectives To investigate whether prenatal Doppler parameters in growth-restricted fetuses are correlated with neonatal circulatory changes. Methods In 43 cases of suspected fetal growth restriction (FGR), serial Doppler measurements of umbilical artery (UA) and middle cerebral artery (MCA)

  12. Acoustic doppler methods for remote measurements of ocean flows - a review

    Digital Repository Service at National Institute of Oceanography (India)

    Joseph, A.

    The evolution of acoustic doppler methods for remote measurements of ocean flows has been briefly reviewed in historical perspective. Both Eulerian and profiling methods have been discussed. Although the first acoustic Doppler current meter has been...

  13. Standardized Approach to Quantitatively Measure Residual Limb Skin Health in Individuals with Lower Limb Amputation

    Science.gov (United States)

    Rink, Cameron L.; Wernke, Matthew M.; Powell, Heather M.; Tornero, Mark; Gnyawali, Surya C.; Schroeder, Ryan M.; Kim, Jayne Y.; Denune, Jeffrey A.; Albury, Alexander W.; Gordillo, Gayle M.; Colvin, James M.; Sen, Chandan K.

    2017-01-01

    Objective: (1) Develop a standardized approach to quantitatively measure residual limb skin health. (2) Report reference residual limb skin health values in people with transtibial and transfemoral amputation. Approach: Residual limb health outcomes in individuals with transtibial (n = 5) and transfemoral (n = 5) amputation were compared to able-limb controls (n = 4) using noninvasive imaging (hyperspectral imaging and laser speckle flowmetry) and probe-based approaches (laser doppler flowmetry, transcutaneous oxygen, transepidermal water loss, surface electrical capacitance). Results: A standardized methodology that employs noninvasive imaging and probe-based approaches to measure residual limb skin health are described. Compared to able-limb controls, individuals with transtibial and transfemoral amputation have significantly lower transcutaneous oxygen tension, higher transepidermal water loss, and higher surface electrical capacitance in the residual limb. Innovation: Residual limb health as a critical component of prosthesis rehabilitation for individuals with lower limb amputation is understudied in part due to a lack of clinical measures. Here, we present a standardized approach to measure residual limb health in people with transtibial and transfemoral amputation. Conclusion: Technology advances in noninvasive imaging and probe-based measures are leveraged to develop a standardized approach to quantitatively measure residual limb health in individuals with lower limb loss. Compared to able-limb controls, resting residual limb physiology in people that have had transfemoral or transtibial amputation is characterized by lower transcutaneous oxygen tension and poorer skin barrier function. PMID:28736682

  14. Standardized Approach to Quantitatively Measure Residual Limb Skin Health in Individuals with Lower Limb Amputation.

    Science.gov (United States)

    Rink, Cameron L; Wernke, Matthew M; Powell, Heather M; Tornero, Mark; Gnyawali, Surya C; Schroeder, Ryan M; Kim, Jayne Y; Denune, Jeffrey A; Albury, Alexander W; Gordillo, Gayle M; Colvin, James M; Sen, Chandan K

    2017-07-01

    Objective: (1) Develop a standardized approach to quantitatively measure residual limb skin health. (2) Report reference residual limb skin health values in people with transtibial and transfemoral amputation. Approach: Residual limb health outcomes in individuals with transtibial ( n  = 5) and transfemoral ( n  = 5) amputation were compared to able-limb controls ( n  = 4) using noninvasive imaging (hyperspectral imaging and laser speckle flowmetry) and probe-based approaches (laser doppler flowmetry, transcutaneous oxygen, transepidermal water loss, surface electrical capacitance). Results: A standardized methodology that employs noninvasive imaging and probe-based approaches to measure residual limb skin health are described. Compared to able-limb controls, individuals with transtibial and transfemoral amputation have significantly lower transcutaneous oxygen tension, higher transepidermal water loss, and higher surface electrical capacitance in the residual limb. Innovation: Residual limb health as a critical component of prosthesis rehabilitation for individuals with lower limb amputation is understudied in part due to a lack of clinical measures. Here, we present a standardized approach to measure residual limb health in people with transtibial and transfemoral amputation. Conclusion: Technology advances in noninvasive imaging and probe-based measures are leveraged to develop a standardized approach to quantitatively measure residual limb health in individuals with lower limb loss. Compared to able-limb controls, resting residual limb physiology in people that have had transfemoral or transtibial amputation is characterized by lower transcutaneous oxygen tension and poorer skin barrier function.

  15. Residual-stress measurements

    Energy Technology Data Exchange (ETDEWEB)

    Ezeilo, A.N.; Webster, G.A. [Imperial College, London (United Kingdom); Webster, P.J. [Salford Univ. (United Kingdom)

    1997-04-01

    Because neutrons can penetrate distances of up to 50 mm in most engineering materials, this makes them unique for establishing residual-stress distributions non-destructively. D1A is particularly suited for through-surface measurements as it does not suffer from instrumental surface aberrations commonly found on multidetector instruments, while D20 is best for fast internal-strain scanning. Two examples for residual-stress measurements in a shot-peened material, and in a weld are presented to demonstrate the attractive features of both instruments. (author).

  16. Mesospheric temperatures from observations of the hydroxyl (6–2 emission above Davis, Antarctica: A comparison of rotational and Doppler measurements

    Directory of Open Access Journals (Sweden)

    J. L. Innis

    Full Text Available We present observations of the hydroxyl (6–2 airglow lines from ~ 87 km altitude obtained at Davis station, Antarctica, in the austral winter of 1999. Nine nights of observations were made of the P-branch near λ840 nm with a Czerny-Turner scanning spectrometer (CTS; at the same time, high-resolution Fabry-Perot Spectrometer (FPS spectra were collected of the Q1(1 doublet at λ834 nm. Rotational temperatures were determined from the CTS observations, while Doppler temperatures were derived from the line-widths of the FPS Q1(1 spectra. Absolute temperatures determined by these methods are uncertain by ~ 2 and ~ 20 K, respectively. For the comparison we set the value of the reflective finesse of the FPS at λ834 nm so the mean FPS temperature from one night of simultaneous data was equal to that from the CTS, and then looked at the measured variations in each data set for the other eight nights. Both instruments show the upper mesosphere temperature to vary in a similar manner to within the observational errors of the measurements, implying an equivalence of the rotational and Doppler temperatures. We believe that this is the first published simultaneous, same-site, comparison of rotational and Doppler temperatures from the OH emission.

    Key words. Atmospheric composition and structure (airglow and aurora; pressure density and temperature; instruments and techniques

  17. Measurements of ion temperature and flow of pulsed plasmas produced by a magnetized coaxial plasma gun device using an ion Doppler spectrometer

    Science.gov (United States)

    Kitagawa, Y.; Sakuma, I.; Iwamoto, D.; Kikuchi, Y.; Fukumoto, N.; Nagata, M.

    2012-10-01

    It is important to know surface damage characteristics of plasma-facing component materials during transient heat and particle loads such as type I ELMs. A magnetized coaxial plasma gun (MCPG) device has been used as transient heat and particle source in ELM simulation experiments. Characteristics of pulsed plasmas produced by the MCPG device play an important role for the plasma material interaction. In this study, ion temperature and flow velocity of pulsed He plasmas were measured by an ion Doppler spectrometer (IDS). The IDS system consists of a light collection system including optical fibers, 1m-spectrometer and a 16 channel photomultiplier tube (PMT) detector. The IDS system measures the width and Doppler shift of HeII (468.58 nm) emission line with the time resolution of 1 μs. The Doppler broadened and shifted spectra were measured with 45 and 135 degree angles with respect to the plasmoid traveling direction. The observed emission line profile was represented by sum of two Gaussian components to determine the temperature and flow velocity. The minor component at around the wavelength of zero-velocity was produced by the stationary plasma. As the results, the ion velocity and temperature were 68 km/s and 19 eV, respectively. Thus, the He ion flow energy is 97 eV. The observed flow velocity agrees with that measured by a time of flight technique.

  18. On acceleration dependence of Doppler effect in light

    Indian Academy of Sciences (India)

    Doppler effect involves [1–3] a shift in the wavelength or the frequency of a wave when its source and the observer are in relative motion. As is well known [1–3], this effect is analysed, classically, for sound by using the. (Newtonian) law of addition of velocities. However, this law of addition of velocities was.

  19. A Prospective Study of Doppler Velocimetry in Pregnancy-induced ...

    African Journals Online (AJOL)

    Mubeen

    KEY WORDS: Doppler study, fetomaternal outcome, pregnancy-induced hypertension. INTRODUCTION. Pregnancy-induced hypertension (PIH) remains a great challenge to obstetricians. Impaired utero-placental blood flow in PIH may result in intrauterine growth restriction. (IUGR), placental abruption and intrauterine fetal ...

  20. Usefulness of Doppler Parameter in Patients with Renal Transplantation

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Yeo Chang; Shin, Byung Seok; Ohm, Joon Young; Ahn, Moon Sang [Chungnam National University Hospital, Daejeon (Korea, Republic of); Park, Mi Hyun [Dept. of Radiology, Dankook University Hospital, Cheonan (Korea, Republic of); Kim, Ho Jun [Dept. of Radiology, Konyang University Hospital, Daejeon (Korea, Republic of)

    2012-08-15

    The purpose of this study is to assess the usefulness of Doppler parameters in transplanted kidney function. Doppler parameters, including resistive index (RI), pulsatility index (PI), peak systolic velocity (PSV), and end diastolic velocity (EDV) were measured in the interlobar artery of 55 transplant recipients. Patients were grouped according to glomerular filtration rate (GFR): Group A (GFR < 30 ml / min / 1.73 m2, n = 27) and group B (GFR {>=}30 ml / min / 1.73 m2, n = 28). Doppler parameters were compared between groups and correlated with the GFR. GFR (40.1 {+-} 26.9) showed a significant negative correlation with RI (0.69{+-}.08) (p = .002, r = -.414). RI (0.72 vs. 0.67), PI (1.42 vs. 1.23), and EDV (10.5 vs. 15.3) differed significantly between groups (p < .05), however, PSV was not (36.9 vs. 47.1). Patients in group A (n = 11) with a lower RI than the mean had significantly lower PSV (31.7 vs. 45.1; p = .027) and EDV (11.1 vs. 16.7; p .017), compared with such patients in group B (n = 21). Doppler parameters are useful for evaluation of function of transplanted kidney. Even if the RI is normal, PSV and EDV may be used as hemodynamic indicators.

  1. Doppler Spectrum from Moving Scatterers in a Random Environment

    DEFF Research Database (Denmark)

    Andersen, Jørgen Bach; Nielsen, Jesper Ødum; Pedersen, Gert Frølund

    2009-01-01

    A random non-line-of-sight environment with stationary transmitter and receiver is considered. In such an environment movement of a scatterer will lead to perturbations of the otherwise static channel with a resulting Doppler spectrum. This is quite a general situation in outdoor environments...

  2. Coronary Flow Velocity Reserve Assessed by Transthoracic Doppler

    DEFF Research Database (Denmark)

    Michelsen, Marie M; Peña, Adam; Mygind, Naja D

    2016-01-01

    BACKGROUND: Coronary flow velocity reserve (CFVR) measured by transthoracic Doppler echocardiography is a noninvasive measure of microvascular function, but it has not achieved widespread use, mainly because of concerns of validity and feasibility. The aim of this study was to describe the feasib...

  3. Anomaly Detection In Additively Manufactured Parts Using Laser Doppler Vibrometery

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez, Carlos A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2015-09-29

    Additively manufactured parts are susceptible to non-uniform structure caused by the unique manufacturing process. This can lead to structural weakness or catastrophic failure. Using laser Doppler vibrometry and frequency response analysis, non-contact detection of anomalies in additively manufactured parts may be possible. Preliminary tests show promise for small scale detection, but more future work is necessary.

  4. Laser Doppler perfusion monitoring and imaging: novel approaches

    NARCIS (Netherlands)

    Humeau, Anne; Steenbergen, Wiendelt; Nilsson, Henrik; Strömberg, Tomas

    2007-01-01

    Laser Doppler flowmetry (LDF) is a non invasive method enabling the monitoring of microvascular blood flow, a very important marker of tissue health. This article gives an overview on the concept of LDF for microvascular perfusion monitoring and imaging. It first describes the theoretical background

  5. Correlation between Spectral Index and Doppler Factor for a ...

    Indian Academy of Sciences (India)

    2013). The correlation between Doppler factor and the spectral index can be discussed using a bigger sample. The relativistic beaming effects are also discussed in this proceedings (Li et al. 2014; Wu et al. 2014; Nie et al. 2014). The effective spectral index αOX is anticorre- lated with the viewing angle, and claimed to be ...

  6. Augmented Reality Based Doppler Lidar Data Visualization: Promises and Challenges

    Directory of Open Access Journals (Sweden)

    Cherukuru N. W.

    2016-01-01

    As a proof of concept, we used the lidar data from a recent field campaign and developed a smartphone application to view the lidar scan in augmented reality. In this paper, we give a brief methodology of this feasibility study, present the challenges and promises of using AR technology in conjunction with Doppler wind lidars.

  7. Processor operated correlator with applications to laser Doppler signals

    DEFF Research Database (Denmark)

    Bisgaard, C.; Johnsen, B.; Hassager, Ole

    1984-01-01

    A 64-channel correlator is designed with application to the processing of laser Doppler anemometry signals in the range 200 Hz to 250 kHz. The correlator is processor operated to enable the consecutive sampling of 448 correlation functions at a rate up to 500 Hz. Software is described to identify...

  8. Measuring Velocity and Acceleration Using Doppler Shift of a ...

    Indian Academy of Sciences (India)

    . 1. Introduction ... Doppler effect demands that time is universal, and not relative. We emphasize then that, we do not ..... the material ejected by the prime mover at a later time and is being obstructed by material the jet is ramming into. Then, let ...

  9. Assessment of Uterine and Umbilical Arteries Doppler Indices in ...

    African Journals Online (AJOL)

    Pregnancy induced hypertension (PIH) is a major cause of maternal and perinatal morbidity and mortality in developing countries including Nigeria. Doppler velocimetric indices of the uterine and umbilical arteries may predict the impact of PIH on perfusion of the uteroplacental and fetoplacental circulations respectively.

  10. Passive emitter location with Doppler frequency and interferometric measurements

    NARCIS (Netherlands)

    Groot, J.S.; Dam, F.A.M.; Theil, A.

    2008-01-01

    Ground based emitters can be located with a receiver installed on an airborne platform. This paper discusses techniques based on Doppler frequency and differential phase measurements (interferometry). Measurements of the first technique are provided, while we discuss and compare the theoretical

  11. Role of color Doppler ultrasound in the diagnosis of nonpalpable ...

    African Journals Online (AJOL)

    excluded from the study. Color Doppler was performed in all cases, followed by laparoscopy. Further, findings on laparoscopy were compared with those of CDUS. A 95% confidence interval for the sensitivity of CDUS was estimated considering a positive result on CDUS as the binomial variable. Results. Out of 25 patients, ...

  12. Radar Micro-Doppler classification of Mini-UAVs

    NARCIS (Netherlands)

    Harmanny, R.L.A.; Prémel-Cabic, G.; Wit, J.J.M.

    2015-01-01

    The radar micro-Doppler signature of a target depends on its micro-motion, i.e., the motion of parts of a target relative to the motion of the target as a whole. These micro-motions are very characteristic considering different target classes, e.g., the slow pendulum-like motion of a bird’s wings

  13. Cardiac Time Intervals by Tissue Doppler Imaging M-Mode

    DEFF Research Database (Denmark)

    Biering-Sørensen, Tor; Mogelvang, Rasmus; de Knegt, Martina Chantal

    2016-01-01

    PURPOSE: To define normal values of the cardiac time intervals obtained by tissue Doppler imaging (TDI) M-mode through the mitral valve (MV). Furthermore, to evaluate the association of the myocardial performance index (MPI) obtained by TDI M-mode (MPITDI) and the conventional method of obtaining...

  14. Ultrasonography and color Doppler in juvenile idiopathic arthritis

    DEFF Research Database (Denmark)

    Laurell, Louise; Court-Payen, Michel; Nielsen, Susan

    2011-01-01

    Background The ankle region is frequently involved in juvenile idiopathic arthritis (JIA) but difficult to examine clinically due to its anatomical complexity. The aim of the study was to evaluate the role of ultrasonography (US) of the ankle and midfoot (ankle region) in JIA. Doppler-US detected...

  15. Ultrasonography and color Doppler in juvenile idiopathic arthritis

    DEFF Research Database (Denmark)

    Laurell, Louise; Court-Payen, Michel; Nielsen, Susan

    2012-01-01

    The wrist region is one of the most complex joints of the human body. It is prone to deformity and functional impairment in juvenile idiopathic arthritis (JIA), and is difficult to examine clinically. The aim of this study was to evaluate the role of ultrasonography (US) with Doppler in diagnosis...

  16. Renal Doppler Indices in Children with Nephrotic Syndrome ...

    African Journals Online (AJOL)

    Summary: The resistive and pulsatility indices are known tools for assessing renal function in kidney diseases, especially in proteinuric conditions like Paediatric Nephrotic syndrome (NS) which is a glomerular disease. However, there is a limited knowledge in the use of Doppler Resistive and pulsatility indices in the ...

  17. Doppler Bubble Grades After Diving and Relevance of Body Fat

    NARCIS (Netherlands)

    Schellart, Nico A. M.; Vellinga, Tjeerd P. van Rees; Van Dijk, Frank J.; Sterk, Wouter

    2012-01-01

    SCHELLART NAM, VAN REES VELLINGA TP, VAN DIJK FJ, STERK W. Doppler bubble grades after diving and relevance of body fat. Aviat Space Environ Med 2012; 83:951-7. Background: From the literature on venous gas embolism (VGE) and decompression sickness (DCS), it remains unclear whether body fat is a

  18. Diagnostic sensitivity and specificity of Doppler ultrasound in rheumatoid arthritis

    DEFF Research Database (Denmark)

    Terslev, L.; Recke, P. von der; Torp-Pedersen, S.

    2008-01-01

    Objective. To evaluate the sensitivity and specificity of Doppler ultrasound (DUS) in diagnosing arthritis in the wrist and hands, and, if possible, to define a cutoff level for our ultrasound measures for inflammation, resistive index (RI), and color fraction. Methods. Using DUS, 88 patients...

  19. Color M-mode and pulsed wave tissue Doppler echocardiography

    DEFF Research Database (Denmark)

    Møller, J E; Søndergaard, E; Poulsen, S H

    2001-01-01

    To assess the association between color M-mode flow propagation velocity and the early diastolic mitral annular velocity (E(m)) obtained with tissue Doppler echocardiography and to assess the prognostic implications of the indexes, echocardiography was performed on days 1 and 5, and 1 and 3 months...

  20. Applications of doppler effect in navigation and oceanography

    Digital Repository Service at National Institute of Oceanography (India)

    Joseph, A.

    The Doppler effect is the change in frequency of the received sound waves/electromagnetic waves when there is a relative motion between the transmitter and the receiver of these waves. This effect is used for diverse applications in different areas...

  1. Laser frequency stabilization and large detuning by Doppler-free ...

    Indian Academy of Sciences (India)

    We present results of a study of frequency stabilization of a diode laser ( = 780 nm) using the Doppler-free dichroic lock (DFDL) technique and its use for laser cooling of atoms. Quantitative measurements of frequency stability were performed and the Allan variance was found to be 6.9 × 10−11 for an averaging time of 10 ...

  2. Measuring Velocity and Acceleration Using Doppler Shift of a ...

    Indian Academy of Sciences (India)

    2016-01-27

    Jan 27, 2016 ... Abstract. We describe here as to how the Doppler shift of a source needs to be used to measure its velocity and acceleration. We also apply this method, as an example here, to spectral lines of the blue-shifted jet in micro-quasar SS433 and discuss the intricacies of these measurements.

  3. Comparison between a newly developed PC-based Doppler ...

    African Journals Online (AJOL)

    Objectives. To determine the accuracy of the resistance index (RI) of flow velocity waveforms of the umbilical artery measured using a newly developed PC-based continuous wave Doppler device (Umbiflow) with regard to systematic and random variations when compared with a commercial standard (Vasoflow). Design.

  4. Doppler Lidar in the Wind Forecast Improvement Projects

    Directory of Open Access Journals (Sweden)

    Pichugina Yelena

    2016-01-01

    Full Text Available This paper will provide an overview of some projects in support of Wind Energy development involving Doppler lidar measurement of wind flow profiles. The high temporal and vertical resolution of these profiles allows the uncertainty of Numerical Weather Prediction models to be evaluated in forecasting dynamic processes and wind flow phenomena in the layer of rotor-blade operation.

  5. Fiber-based coherent pulsed Doppler lidar for atmospheric monitoring

    Science.gov (United States)

    Pearson, Guy N.; Eacock, Justin R.

    2002-01-01

    A pulsed Doppler lidar for short range atmospheric backscatter measurements has been developed using fiber- optic components. The system employs a MOPA architecture and operates at a wavelength of 1.548 micrometers in a short pulse, low pulse energy, high repetition rate mode with a 30 mm diameter monostatic aperture. Details of the design and performance are given.

  6. Comparision of doppler studies in obstetrics with foetal outcome ...

    African Journals Online (AJOL)

    Subjects: One hundread and twenty one consecutive female subjects, between 24 and 443 years of age, at or over 28 weeks gestation, referred to the Radiology Department of Aga Khan University Hospital for obstetric doppler ultrasonography. Main outcome measures: Foetal outcome was defined as poor by using either ...

  7. Laser frequency stabilization and large detuning by Doppler-free ...

    Indian Academy of Sciences (India)

    method for frequency stabilization of these lasers is based on saturated absorption spectroscopy (SAS) [3]. The laser frequency is locked either at the center or at the side of a narrow peak in the Doppler-free high-resolution saturated absorp- tion spectrum of the atom. Locking at the side of the peak is straightforward and.

  8. Value of dobutamine stress tissue Doppler in evaluation of LV ...

    African Journals Online (AJOL)

    Aim: To clarify the value of dobutamine stress tissue Doppler in the evaluation of LV functional improvement after elective PCI. Methods: The study included 60 patients with hibernating viable myocardium proved by DSE referred for an evaluation of myocardial viability prior to revascularization. Hemodynamic and ...

  9. A simplified study of trans-mitral Doppler patterns

    Directory of Open Access Journals (Sweden)

    Thomas George

    2008-11-01

    Full Text Available Abstract Background Trans-mitral Doppler produces complex patterns with a great deal of variability. There are several confusing numerical measures and indices to study these patterns. However trans-mitral Doppler produces readymade data visualization by pattern generation which could be interpreted by pattern analysis. By following a systematic approach we could create an order and use this tool to study cardiac function. Presentation of the hypothesis In this new approach we eliminate the variables and apply pattern recognition as the main criterion of study. Proper terminologies are also devised to avoid confusion. In this way we can get some meaningful information. Testing the hypothesis Trans-mitral Doppler should be seen as patterns rather than the amplitude. The hypothesis can be proven by logical deduction, extrapolation and elimination of variables. Trans-mitral flow is also analyzed vis-à-vis the Starling's Law applied to the left atrium. Implications of the hypothesis Trans-mitral Doppler patterns are not just useful for evaluating diastolic function. They are also useful to evaluate systolic function. By following this schema we could get useful diagnostic information and therapeutic options using simple pattern recognition with minimal measurements. This simplified but practical approach will be useful in day to day clinical practice and help in understanding cardiac function better. This will also standardize research and improve communication.

  10. A simplified study of trans-mitral Doppler patterns.

    Science.gov (United States)

    Thomas, George

    2008-11-28

    Trans-mitral Doppler produces complex patterns with a great deal of variability. There are several confusing numerical measures and indices to study these patterns. However trans-mitral Doppler produces readymade data visualization by pattern generation which could be interpreted by pattern analysis. By following a systematic approach we could create an order and use this tool to study cardiac function. In this new approach we eliminate the variables and apply pattern recognition as the main criterion of study. Proper terminologies are also devised to avoid confusion. In this way we can get some meaningful information. Trans-mitral Doppler should be seen as patterns rather than the amplitude. The hypothesis can be proven by logical deduction, extrapolation and elimination of variables. Trans-mitral flow is also analyzed vis-à-vis the Starling's Law applied to the left atrium. Trans-mitral Doppler patterns are not just useful for evaluating diastolic function. They are also useful to evaluate systolic function. By following this schema we could get useful diagnostic information and therapeutic options using simple pattern recognition with minimal measurements. This simplified but practical approach will be useful in day to day clinical practice and help in understanding cardiac function better. This will also standardize research and improve communication.

  11. Transcranial Doppler for detection of cerebral ischaemia during carotid endarterectomy

    DEFF Research Database (Denmark)

    Jørgensen, L G; Schroeder, T V

    1992-01-01

    We evaluated transcranial Doppler sonography (TCD) for the detection of cerebral ischaemia during carotid endarterectomy in 30 male and 14 female patients with ipsilateral focal cerebro-vascular symptoms. Surgery was performed during halothane-nitrous oxide anaesthesia with moderate hypocapnia...

  12. A Prospective Study of Doppler Velocimetry in Pregnancy-induced ...

    African Journals Online (AJOL)

    Doppler studies were carried, and parameters recorded in uterine, umbilical and middle cerebral artery (MCA) were Systolic/Diastolic ratio, Resistance Index, Cerebro Placental Index (CPI). Fetal outcomes were monitored. Statistical analysis was performed using Epi InfoTM software (Version 3.5.1, CDC, Atlanta). Test for ...

  13. Distribution of Doppler Redshifts of Associated Absorbers of SDSS ...

    Indian Academy of Sciences (India)

    are more common than the broad absorption lines. (Richards 2001; Wild et al. 2008; Shen .... culated with the emission redshifts based on the broad Mg II centroid) were selected. 3. Distribution of Doppler redshifts .... absorption lines in quasar spectra seem to be very common (e.g., Nestor et al. 2008;. Hamann et al. 2011).

  14. Predictable progressive Doppler deterioration in IUGR: does it really exist?

    LENUS (Irish Health Repository)

    Unterscheider, Julia

    2013-12-01

    An objective of the Prospective Observational Trial to Optimize Pediatric Health in IUGR (PORTO) study was to evaluate multivessel Doppler changes in a large cohort of intrauterine growth restriction (IUGR) fetuses to establish whether a predictable progressive sequence of Doppler deterioration exists and to correlate these Doppler findings with respective perinatal outcomes.

  15. Radar micro-Doppler of wind turbines : Simulation and analysis using rotating linear wire structures

    NARCIS (Netherlands)

    Krasnov, O.A.; Yarovoy, A.

    2015-01-01

    A simple electromagnetic model of wind-turbine's main structural elements as the linear wired structures is developed to simulate the temporal patterns of observed radar return Doppler spectra (micro-Doppler). Using the model, the micro-Doppler for different combinations of the turbines rotation

  16. Classification of Small UAVs and Birds by Micro-Doppler Signatures

    NARCIS (Netherlands)

    Molchanov, P.; Egiazarian, K.; Astola, J.; Harmanny, R.I.A.; Wit, J.J.M. de

    2013-01-01

    The problem of unmanned aerial vehicles classification using continuous wave radar is considered in this paper. Classification features are extracted from micro-Doppler signature. Before the classification, the micro-Doppler signature is filtered and aligned to compensate the Doppler shift caused by

  17. Pulsed-wave transmitral Doppler do not diagnose moderate acute rejection after heart transplantation

    NARCIS (Netherlands)

    Mannaerts, H. F.; Simoons, M. L.; Balk, A. H.; Tijssen, J.; van der Borden, S. G.; Zondervan, P. E.; Mochtar, B.; Weimar, W.; Roelandt, J. R.

    1993-01-01

    The value of pulsed-wave transmitral Doppler for the diagnosis of moderate acute rejection was examined in a total of 347 Doppler recordings obtained in 32 consecutive cardiac allograft recipients. Serial Doppler examinations (median, 11 per patient; range, 1 to 23) were performed simultaneously

  18. PULSED-WAVE TRANSMITRAL DOPPLER DO NOT DIAGNOSE MODERATE ACUTE REJECTION AFTER HEART-TRANSPLANTATION

    NARCIS (Netherlands)

    MANNAERTS, HF; SIMOONS, ML; BALK, AH; TIJSSEN, J; VANDERBORDEN, SG; ZONDERVAN, PE; MOCHTAR, B; WEIMAR, W; ROELANDT, [No Value

    1993-01-01

    The value of pulsed-wave transmitral Doppler for the diagnosis of moderate acute rejection was examined in a total of 347 Doppler recordings obtained in 32 consecutive cardiac allograft recipients. Serial Doppler examinations (median, 11 per patient; range, 1 to 23) were performed simultaneously

  19. Settings and artefacts relevant for Doppler ultrasound in large vessel vasculitis

    DEFF Research Database (Denmark)

    Terslev, L; Diamantopoulos, A P; Døhn, U Møller

    2017-01-01

    Ultrasound is used increasingly for diagnosing large vessel vasculitis (LVV). The application of Doppler in LVV is very different from in arthritic conditions. This paper aims to explain the most important Doppler parameters, including spectral Doppler, and how the settings differ from those used...

  20. Doppler Compensation for Airborne Non-Side-Looking Phased-Array Radar

    Science.gov (United States)

    2015-09-01

    frequency (Hz) C lu tte r s pe ct ra (d B ) Figure 14: Channel-based N Doppler spectra of the simulated clutter data for a radar operating in the...30 -20 -10 0 10 20 30 40 Doppler frequency (Hz) C lu tte r s pe ct ra (d B ) Figure 16: Channel-based N Doppler spectra of the simulated clutter

  1. Hydronephrosis and pregnancy: study with Doppler echography. Hidronefrosis y embarazo: estudio mediante ecografia Doppler

    Energy Technology Data Exchange (ETDEWEB)

    Ripolles Gonzalez, T.R.; Ambit Capdevilla, S.; Sanguesa Nebot, C.; Lazaro, S. de; Garcia Vila, J.H.; Belloch Ugarte, V.

    1993-01-01

    An 18-month study was performed to establish the normal intrarenal resistance index during pregnancy, in order to determine whether it differed significantly depending on the week of gestation or the degree of hydronephrosis. For this purpose , the flow velocity waves obtained in right kidney were analyzed in a group of 112 patients on the basis of 209 explorations. The kidneys were classified as grade 0,I,II, or III according to the degree of hydronephrosis. Doppler signal sampling was carried out at the level of the corticomedullary junction. From the results of the study it can be deduced that the index of intrarenal resistance during pregnancy is similar to that of the general population, that there are no significant differences among the groups with different degree of hydronephrosis and that the index does not vary according to the different weeks of gestation. These findings suggest that, during pregnancy, a pathological resistance index in a kidney should not be attributed to the physiological changes associated with normal gestation. (Author) 21 refs.

  2. Effects of Lane Width, Lane Position and Edge Shoulder Width on Driving Behavior in Underground Urban Expressways: A Driving Simulator Study

    Directory of Open Access Journals (Sweden)

    Shuo Liu

    2016-10-01

    Full Text Available This study tested the effects of lane width, lane position and edge shoulder width on driving behavior for a three-lane underground urban expressway. A driving simulator was used with 24 volunteer test subjects. Five lane widths (2.85, 3.00, 3.25, 3.50, and 3.75 m and three shoulder widths (0.50, 0.75, and 1.00 m were studied. Driving speed, lane deviation and subjective perception of driving behavior were collected as performance measures. The results show that lane and shoulder width have significant effects on driving speed. Average driving speed increases from 60.01 km/h in the narrowest lane to 88.05 km/h in the widest lane. While both narrower lanes and shoulders result in reduced speed and lateral lane deviation, the effect of lane width is greater than that of shoulder width. When the lane and shoulder are narrow, drivers in the left or right lane tend to shy away from the tunnel wall, even encroaching into the neighboring middle lane. As the lane or shoulder gets wider, drivers tend to stay in the middle of the lane. An interesting finding is that although few participants acknowledged that lane position had any great bearing on their driving behaviors, the observed driving speed is statistically higher in the left lane than in the other two lanes when the lane width is narrow (in 2.85, 3 and 3.25 m lanes. These findings provided support for amending the current design specifications of urban underground roads, such as the relationship between design speed and lane width, speed limit, and combination form of lanes.

  3. Composition of carbonization residues

    Energy Technology Data Exchange (ETDEWEB)

    Hupfer; Leonhardt

    1943-11-27

    This report compared the composition of samples from Wesseling and Leuna. In each case the sample was a residue from carbonization of the residues from hydrogenation of the brown coal processed at the plant. The composition was given in terms of volatile components, fixed carbon, ash, water, carbon, hydrogen, oxygen, nitrogen, volatile sulfur, and total sulfur. The result of carbonization was given in terms of (ash and) coke, tar, water, gas and losses, and bitumen. The composition of the ash was given in terms of silicon dioxide, ferric oxide, aluminum oxide, calcium oxide, magnesium oxide, potassium and sodium oxides, sulfur trioxide, phosphorus pentoxide, chlorine, and titanium oxide. The most important difference between the properties of the two samples was that the residue from Wesseling only contained 4% oil, whereas that from Leuna had about 26% oil. Taking into account the total amount of residue processed yearly, the report noted that better carbonization at Leuna could save 20,000 metric tons/year of oil. Some other comparisons of data included about 33% volatiles at Leuna vs. about 22% at Wesseling, about 5 1/2% sulfur at Leuna vs. about 6 1/2% at Leuna, but about 57% ash for both. Composition of the ash differed quite a bit between the two. 1 table.

  4. Designing with residual materials

    NARCIS (Netherlands)

    Walhout, W.; Wever, R.; Blom, E.; Addink-Dölle, L.; Tempelman, E.

    2013-01-01

    Many entrepreneurial businesses have attempted to create value based on the residual material streams of third parties. Based on ‘waste’ materials they designed products, around which they built their company. Such activities have the potential to yield sustainable products. Many of such companies

  5. Alveolar bone width preservation after decoronation of ankylosed anterior incisors.

    Science.gov (United States)

    Lin, Shaul; Schwarz-Arad, Dvorah; Ashkenazi, Malka

    2013-12-01

    The aim of the study was to assess the alteration of alveolar ridge dimensions after decoronation procedures in children and adolescents at least 1 year after surgery. Twelve children who underwent decoronation of ankylosed maxillary anterior incisors with at least 1 year after surgery follow-up were recalled for reevaluation. All decoronations were performed when the ankylosed teeth were submerged 1-1.5 mm. During the recall appointment, impressions of the upper arch were obtained. The bucco-palatal alveolar dimensions of the decoronated teeth were measured on the cast at the mid-mesiodistal distance from the missing tooth and were compared with the distance from the contralateral healthy incisor. Overall, 12 children (9 male and 3 female) were reevaluated up to 82 months after decoronation (mean, 49.58 ± 24 months). The mean age of the patients at the time of trauma was 9.83 ± 2.8 years. The average bucco-palatal dimension of the alveolar ridge at the mid-decoronation area was 9 ± 1 mm compared with 10.17 ± 0.9 mm at the contralateral homologous tooth (difference of 1.67 ± 1.12, P = .004). The findings show a positive statistical correlation between the duration of the follow-up period and the bucco-palatal dimension of the alveolar ridge (P = .027). Although decoronation of ankylosed young permanent incisors resulted in a decrease in the bucco-palatal dimension with time, it did not prevent additional alveolar growth that occurs with age in a developing child and thus may help maintain the alveolar bone ridge width, height, and continuity and assist in future rehabilitation with less invasive ridge augmentation procedures required for implant placement. Copyright © 2013 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  6. Errors when shock waves interact due to numerical shock width

    Energy Technology Data Exchange (ETDEWEB)

    Menikoff, R.

    1993-03-04

    A simple test problem proposed by Noh, a strong shock reflecting from a rigid wall, demonstrates a generic problem with numerical shock capturing algorithms at boundaries that Noh called ``excess wall heating.`` We show that the same type of numerical error occurs in general when shock waves interact. The underlying cause is the non-uniform convergence to the hyperbolic solution of the inviscid limit of the solution to the PDEs with viscosity. The error can be understood from an analysis of the asymptotic solution. For a propagating shock, there is a difference in the total energy of the parabolic wave relative to the hyperbolic shock. Moreover, the relative energy depends on the strength of the shock. The error when shock waves interact is due to the difference in the relative energies between the incoming and outgoing shock waves. It is analogous to a phase shift in a scattering matrix. A conservative differencing scheme correctly describes the Hugoniot jump conditions for a steady propagating shock. Therefore, the error from the asymptotics occurs in the transient when the waves interact. The entropy error that occurs in the interaction region remains localized but does not dissipate. A scaling argument shows that as the viscosity coefficient goes to zero, the error shrinks in spatial extend but is constant in magnitude. Noh`s problem of the reflection of a shock from a rigid wall is equivalent to the symmetric impact of two shock waves of the opposite family. The asymptotic argument shows that the same type of numerical error would occur when the shocks are of unequal strength. Thus, Noh`s problem is indicative of a numerical error that occurs when shocks interact due to the numerical shock width.

  7. Errors when shock waves interact due to numerical shock width

    Energy Technology Data Exchange (ETDEWEB)

    Menikoff, R.

    1993-03-04

    A simple test problem proposed by Noh, a strong shock reflecting from a rigid wall, demonstrates a generic problem with numerical shock capturing algorithms at boundaries that Noh called excess wall heating.'' We show that the same type of numerical error occurs in general when shock waves interact. The underlying cause is the non-uniform convergence to the hyperbolic solution of the inviscid limit of the solution to the PDEs with viscosity. The error can be understood from an analysis of the asymptotic solution. For a propagating shock, there is a difference in the total energy of the parabolic wave relative to the hyperbolic shock. Moreover, the relative energy depends on the strength of the shock. The error when shock waves interact is due to the difference in the relative energies between the incoming and outgoing shock waves. It is analogous to a phase shift in a scattering matrix. A conservative differencing scheme correctly describes the Hugoniot jump conditions for a steady propagating shock. Therefore, the error from the asymptotics occurs in the transient when the waves interact. The entropy error that occurs in the interaction region remains localized but does not dissipate. A scaling argument shows that as the viscosity coefficient goes to zero, the error shrinks in spatial extend but is constant in magnitude. Noh's problem of the reflection of a shock from a rigid wall is equivalent to the symmetric impact of two shock waves of the opposite family. The asymptotic argument shows that the same type of numerical error would occur when the shocks are of unequal strength. Thus, Noh's problem is indicative of a numerical error that occurs when shocks interact due to the numerical shock width.

  8. Renal Doppler indices in diabetic children with insulin resistance syndrome.

    Science.gov (United States)

    Abd El Ghaffar, Shereen; El Kaffas, Khaled; Hegazy, Ranya; Mostafa, Mohamed

    2010-11-01

    End-stage renal failure is still a leading cause of mortality among type 1 diabetes patients. Insulin resistance plays a larger role in type 1 diabetes disease process than is commonly recognized. Detection of diabetic nephropathy as early as possible currently offers the best chance of delaying or possibly preventing progression to end-stage disease. Renal resistive index (RI) and pulsatility index (PI), measured using renal Doppler ultrasonography, reflect intrarenal vascular resistance. The present work aimed at examining renal Doppler indices (RI and PI) in type 1 diabetic children and their relation to features of insulin resistance and other established parameters of early diabetic nephropathy as microalbuminuria. One hundred diabetic children with a mean age of 13.4 ± 2.9 yr and an average diabetes duration of (7.2 ± 2.5 yr) were included. Thirty healthy children served as controls. All renal Doppler indices were significantly higher in children with type 1 diabetes mellitus (p ≤ 0.01). The worst parameters were observed in children diagnosed with insulin resistance syndrome (IRS) (38%), hypertensive (12%), and obese (4%) children. Resistive index showed a significant correlation to blood pressure (r = 0.2, p = 0.04), waist-hip ratio (r = 0.5, p = 0.02), insulin dose (r = 0.2, p = 0.02) and estimated glucose disposal rate (r = -0.5, p = 0.01). No correlation was noted to microalbuminuria, HbA1c, or duration of diabetes. The present work concluded that renal Doppler indices are worse in diabetic children and particularly those with IRS. These children appear to be at graver risk for diabetic nephropathy. In these patients adding renal Doppler assessment to their work up, might diagnose diabetic nephropathy at a prealbuminuric stage. © 2010 John Wiley & Sons A/S.

  9. Effectiveness of Pulse Oximetry Versus Doppler for Tourniquet Monitoring.

    Science.gov (United States)

    Wall, Piper L; Buising, Charisse M; Grulke, Lisa; Troester, Alexander; Bianchina, Nicholas; White, Shannon; Freymark, Rosemarie; Hassan, Ali; Hopkins, James W; Renner, Catherine Hackett; Sahr, Sheryl M

    Pulse oximeters are common and include arterial pulse detection as part of their methodology. The authors investigated the possible usefulness of pulse oximeters for monitoring extremity tourniquet arterial occlusion. Tactical Ratcheting Medical Tourniquets were tightened to the least Doppler-determined occluding pressure at mid-thigh or mid-arm locations on one limb at a time on all four limbs of 15 volunteers. A randomized block design was used to determine the placement locations of three pulse oximeter sensors on the relevant digits. The times and pressures of pulsatile signal absences and returns were recorded for 200 seconds, with the tourniquet being tightened only when the Doppler ultrasound and all three pulse oximeters had pulsatile signals present (pulsatile waveform traces for the pulse oximeters). From the first Doppler signal absence to tourniquet release, toe-located pulse oximeters missed Doppler signal presence 41% to 50% of the times (discrete 1-second intervals) and missed 39% to 49% of the pressure points (discrete 1mmHg intervals); fingerlocated pulse oximeters had miss rates of 11% to 15% of the times and 13% to 19% of the pressure points. On toes, the pulse oximeter ranges of sensitivity and specificity for Doppler pulse detection were 71% to 90% and 44% to 51%, and on fingers, the respective ranges were 65% to 77% and 78% to 83%. Use of a pulse oximeter to monitor limb tourniquet effectiveness will result in some instances of an undetected weak arterial pulse being present. If a pulse oximeter waveform is obtained from a location distal to a tourniquet, the tourniquet should be tightened. If a pulsatile waveform is not detected, vigilance should be maintained. 2017.

  10. Doppler ultrasound scan during normal gestation: umbilical circulation

    International Nuclear Information System (INIS)

    Ruiz, T.; Sabate, J.; Martinez-Benavides, M. M.; Sanchez-Ramos, J.

    2002-01-01

    To determine normal umbilical circulation patterns by means of Doppler ultrasound scan in a healthy gestating population without risk factors and with normal perinatal results, and to evaluate any occurring modifications relative to gestational age by obtaining records kept during pregnancy. One hundred and sixteen pregnant women carrying a single fetus have been studied. These women had no risk factors, with both clinical and analytical controls, as well as ultrasound scans, all being normal. There were performed a total of 193 Doppler ultrasound scans between weeks 15 and 41 of gestation, with blood-flow analysis in the arteries and vein of the umbilical cord. The obtained information was correlated with parameters that evaluate fetal well-being (fetal monitoring and/or oxytocin test) and perinatal result (delivery type, birth weight, Apgar score). Statistical analysis was performed with the programs SPSS 6.0.1 for Windows and EPIINFO 6.0.4. With pulsed Doppler, the umbilical artery in all cases demonstrated a biphasic morphology with systolic and diastolic components and without retrograde blood flow. As the gestation period increased, there was observed a progressive decrease in resistance along with an increase in blood-flow velocity during the diastolic phase. The Doppler ultrasound scan is a non-invasive method that permits the hemodynamic study of umbilical blood circulation. A knowledge of normal blood-flow signal morphology, as well as of the normal values for Doppler indices in relation to gestational age would permit us to utilize this method in high-risk pregnancies. (Author) 30 refs

  11. Interpretation of the new Ω{sub c}{sup 0} states via their mass and width

    Energy Technology Data Exchange (ETDEWEB)

    Agaev, S.S. [Baku State University, Institute for Physical Problems, Baku (Azerbaijan); Azizi, K. [Dogus University, Department of Physics, Istanbul (Turkey); Sundu, H. [Kocaeli University, Department of Physics, Izmit (Turkey)

    2017-06-15

    The masses and pole residues of the ground and first radially excited Ω{sub c}{sup 0} states with spin-parities J{sup P} = 1/2{sup +}, 3/2{sup +}, as well as P-wave Ω{sub c}{sup 0} with J{sup P} = 1/2{sup -}, 3/2{sup -} are calculated by means of the two-point QCD sum rules. The strong decays of Ω{sub c}{sup 0} baryons are also studied and the widths of these decay channels are computed. The relevant computations are performed in the context of the full QCD sum rules on the light cone. The results obtained for the masses and widths are confronted with recent experimental data of the LHCb Collaboration, which allow us to interpret Ω{sub c}(3000){sup 0}, Ω{sub c}(3050){sup 0}, and Ω{sub c}(3119){sup 0} as the excited css baryons with the quantum numbers (1P, 1/2{sup -}), (1P, 3/2{sup -}), and (2S, 3/2{sup +}), respectively. The (2S, 1/2{sup +}) state can be assigned either to the Ω{sub c}(3066){sup 0} state or the Ω{sub c}(3090){sup 0} excited baryon. (orig.)

  12. Residual Motion and Duty Time in Respiratory Gating Radiotherapy Using Individualized or Population-Based Windows

    International Nuclear Information System (INIS)

    Fuji, Hiroshi; Asada, Yoshihiro; Numano, Masumi; Yamashita, Haruo; Nishimura, Tetsuo; Hashimoto, Takayuki; Harada, Hideyuki; Asakura, Hirofumi; Murayama, Shigeyuki

    2009-01-01

    Purpose: The efficiency and precision of respiratory gated radiation therapy for tumors is affected by variations in respiration-induced tumor motion. We evaluated the use of individualized and population-based parameters for such treatment. Methods and Materials: External respiratory signal records and images of respiration-induced tumor motion were obtained from 42 patients undergoing respiratory gated radiation therapy for liver tumors. Gating window widths were calculated for each patient, with 2, 4, and 10 mm of residual motion, and the mean was defined as the population-based window width. Residual motions based on population-based and predefined window widths were compared. Duty times based on whole treatment sessions, at various window levels, were calculated. The window level giving the longest duty time was defined as the individualized most efficient level (MEL). MELs were also calculated based on the first 10 breathing cycles. The duty times for population-based MELs (defined as mean MELs) and individualized MELs were compared. Results: Tracks of respiration-induced tumor motion ranged from 3 to 50 mm. Half of the patients had larger actual residual motions than the assigned residual motions. Duty times were greater when based on individualized, rather than population-based, window widths. The MELs established during whole treatment sessions for 2 mm and 4 mm of residual motion gave significantly increased duty times, whereas those calculated using the first 10 breathing cycles showed only marginal increases. Conclusions: Using individualized window widths and levels provided more precise and efficient respiratory gated radiation therapy. However, methods for predicting individualized window levels before treatment remain to be explored.

  13. Red cell distribution width in type 2 diabetic patients.

    Science.gov (United States)

    Nada, Aml Mohamed

    2015-01-01

    To study the indices of some elements of the complete blood count, in type 2 diabetic patients, in comparison with nondiabetic healthy controls; and to find out the effects of glycemic control and different medications on these indices. To the best of our knowledge, this study is novel in our environment and will serve as a foundation for other researchers in this field. This retrospective study included 260 type 2 diabetic patients on treatment and 44 healthy control subjects. Sex, age, weight, height, blood pressure, complete blood count, fasting plasma glucose, hemoglobin A1c (HbA1c), and lipid profile data, were available for all of the study population. For diabetic patients, data on duration of diabetes and all medications were also available. Red cell distribution width (RDW) was significantly higher in diabetic patients than in control subjects (P=0.008). It was also higher in patients with uncontrolled glycemia (HbA1c >7%) than those with good control (HbA1c ≤7%; P=0.035). Mean platelet volume (MPV) was comparable in both diabetic patients and healthy controls (P=0.238). RDW and MPV did not significantly correlate with fasting plasma glucose, HbA1c, or duration of diabetes. Both aspirin and clopidogrel did not show a significant effect on MPV. Both insulin and oral hypoglycemic agents did not show a significant effect on RDW, mean corpuscular volume, MPV, platelet count, or white blood cell count. Diabetic patients treated with indapamide or the combined thiazides and angiotensin receptor blockers showed no significant difference in RDW when compared with the control subjects. RDW, which is recently considered as an inflammatory marker with a significant predictive value of mortality in diseased and healthy populations, is significantly higher in diabetic patients than healthy subjects and is particularly higher in uncontrolled glycemia. None of the studied hypoglycemic agents showed a significant effect on RDW. Diabetic hypertensive patients receiving

  14. Red cell distribution width in type 2 diabetic patients

    Directory of Open Access Journals (Sweden)

    Nada AM

    2015-10-01

    Full Text Available Aml Mohamed Nada Department of Internal Medicine, Unit of Endocrinology, Diabetes and Metabolism, Faculty of Medicine, Mansoura University, Mansoura, Egypt Objective: To study the indices of some elements of the complete blood count, in type 2 diabetic patients, in comparison with nondiabetic healthy controls; and to find out the effects of glycemic control and different medications on these indices. To the best of our knowledge, this study is novel in our environment and will serve as a foundation for other researchers in this field. Methods: This retrospective study included 260 type 2 diabetic patients on treatment and 44 healthy control subjects. Sex, age, weight, height, blood pressure, complete blood count, fasting plasma glucose, hemoglobin A1c (HbA1c, and lipid profile data, were available for all of the study population. For diabetic patients, data on duration of diabetes and all medications were also available. Results: Red cell distribution width (RDW was significantly higher in diabetic patients than in control subjects (P=0.008. It was also higher in patients with uncontrolled glycemia (HbA1c >7% than those with good control (HbA1c ≤7%; P=0.035. Mean platelet volume (MPV was comparable in both diabetic patients and healthy controls (P=0.238. RDW and MPV did not significantly correlate with fasting plasma glucose, HbA1c, or duration of diabetes. Both aspirin and clopidogrel did not show a significant effect on MPV. Both insulin and oral hypoglycemic agents did not show a significant effect on RDW, mean corpuscular volume, MPV, platelet count, or white blood cell count. Diabetic patients treated with indapamide or the combined thiazides and angiotensin receptor blockers showed no significant difference in RDW when compared with the control subjects. Conclusion: RDW, which is recently considered as an inflammatory marker with a significant predictive value of mortality in diseased and healthy populations, is significantly higher in

  15. Statistical distribution of partial widths in the microscopic theory of nuclear reactions

    International Nuclear Information System (INIS)

    Bunakov, V.E.; Ogloblin, S.G.

    1978-01-01

    Using the microscopic theory of nuclear reaction the distribution function of neutron reduced partial widths is obtained. It is shown that the distribution of reduced partial widths of a radiative transition is of the same form. The distribution obtained differs from the Porter-Thomas law for neutron widths only in the presence of intermediate structures. It is noteworthy that the presence of an intermediate structure leads to a greater dispersion

  16. Comparison of tibiofemoral joint space width measurements from standing CT and fixed flexion radiography.

    Science.gov (United States)

    Segal, Neil A; Frick, Eric; Duryea, Jeffrey; Nevitt, Michael C; Niu, Jingbo; Torner, James C; Felson, David T; Anderson, Donald D

    2017-07-01

    The objective of this project was to determine the relationship between medial tibiofemoral joint space width measured on fixed-flexion radiographs and the three-dimensional joint space width distribution on low-dose, standing CT (SCT) imaging. At the 84-month visit of the Multicenter Osteoarthritis Study, 20 participants were recruited. A commercial SCT scanner for the foot and ankle was modified to image knees while standing. Medial tibiofemoral joint space width was assessed on radiographs at fixed locations from 15% to 30% of compartment width using validated software and on SCT by mapping the distances between three-dimensional subchondral bone surfaces. Individual joint space width values from radiographs were compared with three-dimensional joint space width values from corresponding sagittal plane locations using paired t-tests and correlation coefficients. For the four medial-most tibiofemoral locations, radiographic joint space width values exceeded the minimal joint space width on SCT by a mean of 2.0 mm and were approximately equal to the 61st percentile value of the joint space width distribution at each respective sagittal-plane location. Correlation coefficients at these locations were 0.91-0.97 and the offsets between joint space width values from radiographs and SCT measurements were consistent. There were greater offsets and variability in the offsets between modalities closer to the tibial spine. Joint space width measurements on fixed-flexion radiographs are highly correlated with three-dimensional joint space width from SCT. In addition to avoiding bony overlap obscuring the joint, a limitation of radiographs, the current study supports a role for SCT in the evaluation of tibiofemoral OA. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:1388-1395, 2017. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  17. Residual stresses in material processing

    Science.gov (United States)

    Kozaczek, K. J.; Watkins, T. R.; Hubbard, C. R.; Wang, Xun-Li; Spooner, S.

    Material manufacturing processes often introduce residual stresses into the product. The residual stresses affect the properties of the material and often are detrimental. Therefore, the distribution and magnitude of residual stresses in the final product are usually an important factor in manufacturing process optimization or component life prediction. The present paper briefly discusses the causes of residual stresses. It then addresses the direct, nondestructive methods of residual stress measurement by X ray and neutron diffraction. Examples are presented to demonstrate the importance of residual stress measurement in machining and joining operations.

  18. Evaluation of width and width uniformity of near-field electrospinning printed micro and sub-micrometer lines based on optical image processing

    Science.gov (United States)

    Zhao, Libo; Xia, Yong; Hebibul, Rahman; Wang, Jiuhong; Zhou, Xiangyang; Hu, Yingjie; Li, Zhikang; Luo, Guoxi; Zhao, Yulong; Jiang, Zhuangde

    2018-03-01

    This paper presents an experimental study using image processing to investigate width and width uniformity of sub-micrometer polyethylene oxide (PEO) lines fabricated by near-filed electrospinning (NFES) technique. An adaptive thresholding method was developed to determine the optimal gray values to accurately extract profiles of printed lines from original optical images. And it was proved with good feasibility. The mechanism of the proposed thresholding method was believed to take advantage of statistic property and get rid of halo induced errors. Triangular method and relative standard deviation (RSD) were introduced to calculate line width and width uniformity, respectively. Based on these image processing methods, the effects of process parameters including substrate speed (v), applied voltage (U), nozzle-to-collector distance (H), and syringe pump flow rate (Q) on width and width uniformity of printed lines were discussed. The research results are helpful to promote the NFES technique for fabricating high resolution micro and sub-micro lines and also helpful to optical image processing at sub-micro level.

  19. SRC Residual fuel oils

    Science.gov (United States)

    Tewari, Krishna C.; Foster, Edward P.

    1985-01-01

    Coal solids (SRC) and distillate oils are combined to afford single-phase blends of residual oils which have utility as fuel oils substitutes. The components are combined on the basis of their respective polarities, that is, on the basis of their heteroatom content, to assure complete solubilization of SRC. The resulting composition is a fuel oil blend which retains its stability and homogeneity over the long term.

  20. Effects of Adopting Different Kinds of Collecting Method for Years on Film Residual Coefficient and Maize Yields

    Directory of Open Access Journals (Sweden)

    TANG Wen-xue

    2017-03-01

    Full Text Available Wide usage of mulching technology has increased crop yields, but the large amounts of mulching film residue resulting from widespread use of plastic film in China has brought about a series of pollution hazards. Based on a 4-year (2011-2014 long-term experiment, the effects of different kinds of collecting mothod (zero plastic film residues, conventional plastic film residues, whole plastic film residues remainded on plastic film residues, residual coefficient and maize yield were explored. Plastic film residues mainly remained in 0~10 cm, 10~20 cm soil layers. In 0~30 cm soil layers, the two types of mulch residues (>25 cm2, 4~25 cm2 under zero plastic film residues treatment were much less than conventional plastic film residues and whole plastic film residues remainded treatments, no significant differences were observed in the mulch residues (2 among 3 treatments. After maize harvest, the amount of plastic film residues under zero plastic film residues, conventional plastic film residues and whole plastic film residues remainded treatments were 52.71, 80.85 kg·hm-2 and 152.65 kg·hm-2, respectively, the residual coefficient for zero plastic film residues, conventional plastic film residues and whole plastic film residues remainded treatments were -9.45%, 8.53% and 54.42%, respectively. The stem diameter, ear length, ear width, ear row number, grain number per row and 100-grain weight of maize decreased with the increase of residual film amount. Compared with the conventional plastic film residues, the mean grain yield of whole plastic film residues remainded treatment decreased by 15.08%, whereas the zero plastic film residues treatment increased by 4.70%. The plastic film residues, residual coefficient and maize yield were comprehensively analyzed, the conventional plastic film residues practice should be adopted currently without appropriate plastic film residues collector. But from the long-term development, we should speed up the

  1. Composition of carbonization residues

    Energy Technology Data Exchange (ETDEWEB)

    Hupfer; Leonhardt

    1943-11-30

    This report gave a record of the composition of several samples of residues from carbonization of various hydrogenation residue from processing some type of coal or tar in the Bergius process. These included Silesian bituminous coal processed at 600 atm. with iron catalyst, in one case to produce gasoline and middle oil and in another case to produce heavy oil excess, Scholven coal processed at 250 atm. with tin oxalate and chlorine catalyst, Bruex tar processed in a 10-liter oven using iron catalyst, and a pitch mixture from Welheim processed in a 10-liter over using iron catalyst. The values gathered were compared with a few corresponding values estimated for Boehlen tar and Gelsenberg coal based on several assumptions outlined in the report. The data recorded included percentage of ash in the dry residue and percentage of carbon, hydrogen, oxygen, nitrogen, chlorine, total sulfur, and volatile sulfur. The percentage of ash varied from 21.43% in the case of Bruex tar to 53.15% in the case of one of the Silesian coals. Percentage of carbon varied from 44.0% in the case of Scholven coal to 78.03% in the case of Bruex tar. Percentage of total sulfur varied from 2.28% for Bruex tar to a recorded 5.65% for one of the Silesian coals and an estimated 6% for Boehlen tar. 1 table.

  2. [The role of Doppler echocardiography in chronic constrictive pericarditis].

    Science.gov (United States)

    Mahdhaoui, A; Bouraoui, H; Ernez-Hajri, S; Jeridi, G; Saadaoui, A; Ammar, H

    2001-11-01

    Constrictive péricarditis (CCP) is a rare but serious disease. It still poses diagnostic difficulties. The purpose of our work is to study the contribution of the echocardiographic Doppler in the diagnosis of the CCP. The authors report six cases of CCP proven after surgery. Study by ultrasound Doppler of intracardiac blood flow and their respiratory variations showed the existence of abnormalities. The decrease of 25% of the mitral E wave in inspiration compared to the value observed in expiration, the increase of 100% of the ebb in sus hépatic vein in expiration and the modifications of the flux in pulmonary insufficiency are the most reliable signs for the diagnosis of the CCP. This method seems so interesting for the diagnosis and to estimate the degree of constriction of the CCP.

  3. Normal Doppler velocimetry of renal vasculature in Persian cats.

    Science.gov (United States)

    Carvalho, Cibele F; Chammas, Maria C

    2011-06-01

    Renal diseases are common in older cats. Decreased renal blood flow may be the first sign of dysfunction and can be evaluated by Doppler ultrasound. But previous studies suggest that the resistive index (RI) has a low sensitivity for detecting renal disease. Doppler waveforms of renal and intrarenal arteries demonstrate decreased blood flow before there are any changes in the RI. The purpose of this study was to evaluate the normal Doppler flowmetrics parameters of renal arteries (RAs), interlobar arteries (IAs) and abdominal aorta (AO) in adult healthy, Persian cats. Twenty-five Persian cats (13 females and 12 males with mean age of 30 months and an age range 12-60 months) with normal clinical examinations and biochemical tests and normal systemic blood pressure were given B-mode ultrasonographies in order to exclude all nephropathies, including polycystic kidney disease. All measurements were performed on both kidneys. Both kidneys (n=50) were examined by color mapping of the renal vasculature. Pulsed Doppler was used to examine both RAs, the IAs at cranial, middle and caudal sites, and the AO. The RI was calculated for all of the vessels. Early systolic acceleration (ESA) of RA and IA was obtained with Doppler spectral analysis. Furthermore, the ratio indices between RA/AO, and IA/RA velocities were calculated. The mean values of peak systolic velocity (PSV) and the diameter for AO were 53.17±13.46 cm/s and 0.38±0.08 cm, respectively. The mean RA diameter for all 50 kidneys was 0.15±0.02 cm. Considering the velocimetric values in both RAs, the mean PSV and RI that were obtained were 41.17±9.40 cm/s and 0.54±0.07. The RA had a mean ESA of 1.12±1.14 m/s(2) and the calculated upper limit of the reference value was 3.40 m/s(2). The mean renal-aortic ratio was 0.828±0.296. The IA showed PSV and RI values of 32.16±9.33 cm/s and 0.52±0.06, respectively. The mean ESA of all IAs was 0.73±0.61 m/s(2). The calculated upper limit of the reference value was 2.0m

  4. Altered doppler flow patterns in cirrhosis patients: An overview

    Energy Technology Data Exchange (ETDEWEB)

    Iranpour, Pooya; Lall, Chandana; Houshyar, Roozbeh; Helmy, Mohammad; Yang, Albert; Ward, Garrett; Goodwin, Scott C. [Dept. of Radiology, University of California Irvine, Orange (United States); Choi, Joon Il [Dept. of Radiology, Seoul St. Mary' s Hospital, College of Medicine, The Catholic University of Korea, Seoul (Korea, Republic of)

    2016-01-15

    Doppler ultrasonography of the hepatic vasculature is an integral part of evaluating precirrhotic and cirrhotic patients. While the reversal of the portal venous flow is a well-recognized phenomenon, other flow patterns, although not as easily understood, may play an important role in assessing the disease status. This article discusses the different characteristic flow patterns observed from the portal vein, hepatic artery, and hepatic vein in patients with liver cirrhosis or related complications and procedures. Knowledge of these different flow patterns provides additional information that may reinforce the diagnosis of cirrhosis, help in staging, and offer prognostic information for determining the direction of therapy. Doppler ultrasonography is invaluable when liver transplantation is being considered and aids in the diagnosis of cirrhosis and portal hypertension.

  5. Aircraft Wake Vortex Measurement with Coherent Doppler Lidar

    Directory of Open Access Journals (Sweden)

    Wu Songhua

    2016-01-01

    Full Text Available Aircraft vortices are generated by the lift-producing surfaces of the aircraft. The variability of near-surface conditions can change the drop rate and cause the cell of the wake vortex to twist and contort unpredictably. The pulsed Coherent Doppler Lidar Detection and Ranging is an indispensable access to real aircraft vortices behavior which transmitting a laser beam and detecting the radiation backscattered by atmospheric aerosol particles. Experiments for Coherent Doppler Lidar measurement of aircraft wake vortices has been successfully carried out at the Beijing Capital International Airport (BCIA. In this paper, the authors discuss the Lidar system, the observation modes carried out in the measurements at BCIA and the characteristics of vortices.

  6. Cerebrovascular reactivity in migraineurs as measured by transcranial Doppler

    International Nuclear Information System (INIS)

    Thomas, T.D.; Harpold, G.J.

    1990-01-01

    Transcranial Doppler ultrasound is a relatively new diagnostic modality which allows the non-invasive assessment of intracranial circulation. A total of 10 migraine patients were studied and compared to healthy controls without headaches. Migraineurs during the headache-free interval demonstrated excessive cerebrovascular reactivity to CO 2 , evidenced by an increase in middle cerebral artery blood flow velocity of 47% ± 15% compared to 28% ± 14% in controls. Differences between the two study groups revealed no significant decrease in middle cerebral artery blood flow velocity with hypocapnia. However, the differences between middle cerebral artery blood flow velocity during hyperventilation and CO 2 inhalation were significantly different comparing migraineurs and controls. Instability of the baseline blood flow velocities was also noted in migraineurs during the interictal period. Characteristics which may allow differentiation of migraineurs from other headache populations could possibly be obtained from transcranial Doppler ultrasound flow studies. 24 refs., 2 tabs

  7. Assessment of right ventricular systolic function by tissue Doppler echocardiography

    DEFF Research Database (Denmark)

    Kjærgaard, Jesper

    2012-01-01

    This thesis summarizes a series of studies performed in order to assess the clinical usefulness of a novel echocardiographic technology that allows non-invasive assessment of regional right ventricular myocardial velocities and deformation: tissue Doppler echocardiography. While the technology...... is a promising tool for improving our understanding of right ventricular hemodynamics, several aspects of the technology must be evaluated. The accuracy and reproducibility of the technology is evaluated in vitro, and normal values, impact of changes in loading of the right ventricle, response to exercise...... on right ventricular hemodynamics: pulmonary embolism, Arrhythmogenic right ventricular cardiomyopathy and pulmonary regurgitation, the latter in an animal model. The conclusions of the thesis are: Color tissue Doppler echocardiography accurately measures velocities, SR and strain in vitro. No systematic...

  8. Doppler ultrasonography of thepectinis oculiartery in harpy eagles (Harpia harpyja).

    Science.gov (United States)

    de Moraes, Wanderlei; Ferreira, Thiago A C; Somma, André T; Cubas, Zalmir S; Moore, Bret A; Montiani-Ferreira, Fabiano

    2017-01-01

    Twenty harpy eagles ( Harpia harpyja ) without systemic or ocular diseases were examined to measure blood velocity parameters of the pectinis oculi artery using Doppler ultrasonography. Pectinate artery resistive index (RI) and pulsatility index (PI) were investigated using ocular Doppler ultrasonography. The mean RI and PI values across all eyes were 0.44±0.10 and 0.62±0.20 respectively. Low RI and PI values found in the harpy eagle´s pectinis oculi artery compared with the American pekin ducks one and other tissue suggest indeed a high metabolic activity in pecten oculi and corroborates the hypothesis of a nutritional function and/or intraocular pressure regulation.

  9. Doppler Lidar Vertical Velocity Statistics Value-Added Product

    Energy Technology Data Exchange (ETDEWEB)

    Newsom, R. K. [DOE ARM Climate Research Facility, Washington, DC (United States); Sivaraman, C. [DOE ARM Climate Research Facility, Washington, DC (United States); Shippert, T. R. [DOE ARM Climate Research Facility, Washington, DC (United States); Riihimaki, L. D. [DOE ARM Climate Research Facility, Washington, DC (United States)

    2015-07-01

    Accurate height-resolved measurements of higher-order statistical moments of vertical velocity fluctuations are crucial for improved understanding of turbulent mixing and diffusion, convective initiation, and cloud life cycles. The Atmospheric Radiation Measurement (ARM) Climate Research Facility operates coherent Doppler lidar systems at several sites around the globe. These instruments provide measurements of clear-air vertical velocity profiles in the lower troposphere with a nominal temporal resolution of 1 sec and height resolution of 30 m. The purpose of the Doppler lidar vertical velocity statistics (DLWSTATS) value-added product (VAP) is to produce height- and time-resolved estimates of vertical velocity variance, skewness, and kurtosis from these raw measurements. The VAP also produces estimates of cloud properties, including cloud-base height (CBH), cloud frequency, cloud-base vertical velocity, and cloud-base updraft fraction.

  10. Curvature affects Doppler investigation of vessels: implications for clinical practice.

    Science.gov (United States)

    Balbis, S; Roatta, S; Guiot, C

    2005-01-01

    In clinical practice, blood velocity estimations from Doppler examination of curved vascular segments are normally different from those of nearby straight segments. The observed "accelerations," sometimes considered as a sort of stochastic disturbances, can actually be related to very specific physical effects due to vessel curvature (i.e., the development of nonaxial velocity [NAV] components) and the spreading of the axial velocity direction in the Doppler sample volume with respect to the insonation axis. The relevant phenomena and their dependence on the radius of curvature of the vessels and on the insonation angle are investigated with a beam-vessel geometry as close as possible to clinical setting, with the simplifying assumptions of steady flow, mild vessel curvature, uniform ultrasonic beam and complete vessel insonation. The insonation angles that minimize the errors are provided on the basis of the study results.

  11. Doppler reflectometry for the investigation of poloidally propagating density perturbations

    International Nuclear Information System (INIS)

    Hirsch, M.; Baldzuhn, J.; Kurzan, B.; Holzhauer, E.

    1999-01-01

    A modification of microwave reflectometry is discussed where the direction of observation is tilted with respect to the normal onto the reflecting surface. The experiment is similar to scattering where a finite resolution in k-space exists but keeps the radial localization of reflectometry. The observed poloidal wavenumber is chosen by Bragg's condition via the tilt angle and the resolution in k-space is determined by the antenna pattern. From the Doppler shift of the reflected wave the poloidal propagation velocity of density perturbations is obtained. The diagnostic capabilities of Doppler reflectometry are investigated using full wave code calculations. The method offers the possibility to observe changes in the poloidal propagation velocity of density perturbations and their radial shear with a temporal resolution of about 10μs. (authors)

  12. Left coronary arterial blood flow: Noninvasive detection by Doppler US

    International Nuclear Information System (INIS)

    Gramiak, R.; Holen, J.; Moss, A.J.; Gutierrez, O.H.; Picone, A.L.; Roe, S.A.

    1986-01-01

    Continuous wave (CW) and pulsed Doppler ultrasound studies with spectral analysis were used to detect the left coronary arterial blood flow in patients who were undergoing routine echocardiography. The pulmonary artery is a stable ultrasonic landmark from which detection of the blood flow can be effected. The left coronary artery can be distinguished by its blood flow toward the cardiac apex and by specific, functional flow features. Flow patterns vary among the left main, circumflex, and anterior descending arteries; patterns also vary with respiration cycles. In the present study, coronary arterial blood flow was detected in 58 of 70 patients (83%). Findings were validated by selectively injecting an agitated saline contrast medium into the left coronary artery and, in another study, by comparing human Doppler phasic flow waveforms with electromagnetic flowmeter recordings obtained in dogs

  13. Performance evaluation of a thermal Doppler Michelson interferometer system.

    Science.gov (United States)

    Mani, Reza; Dobbie, Steven; Scott, Alan; Shepherd, Gordon; Gault, William; Brown, Stephen

    2005-11-20

    The thermal Doppler Michelson interferometer is the primary element of a proposed limb-viewing satellite instrument called SWIFT (Stratospheric Wind Interferometer for Transport studies). SWIFT is intended to measure stratospheric wind velocities in the altitude range of 15-45 km. SWIFT also uses narrowband tandem etalon filters made of germanium to select a line out of the thermal spectrum. The instrument uses the same technique of phase-stepping interferometry employed by the Wind Imaging Interferometer onboard the Upper Atmosphere Research Satellite. A thermal emission line of ozone near 9 microm is used to detect the Doppler shift due to winds. A test bed was set up for this instrument that included the Michelson interferometer and the etalon filters. For the test bed work, we investigate the behavior of individual components and their combination and report the results.

  14. Novel Doppler laser radar for diagnostics in fusion reactors

    Science.gov (United States)

    Menon, Madhavan; Slotwinski, Anthony

    2004-10-01

    We describe the development of a novel Doppler laser radar (DOLAR) for remote measurement of flow velocity (0-10 m/s) and film thickness of liquid metal walls, currently being studied for their superior heat handling and self-healing characteristics. Small fluctuations in flow velocity(˜mm/s) and flow thickness (˜50 μm) that may arise during plasma discharges can also be measured. The DOLAR is also designed for non intrusive mapping of features of plasma-facing solid surfaces with very high precision (˜50 μm). It can also measure the motion of structural components of a fusion reactor during plasma discharges and during plasma disruptions. The device utilizes frequency modulation laser radar principles for precision range measurements. Compensation of Doppler frequency shift is used to measure flow velocity. The DOLAR probe head is designed with acousto-optic and piezoelectric devices for operation in the harsh fusion environment.

  15. All semiconductor laser Doppler anemometer at 1.55 microm.

    Science.gov (United States)

    Hansen, René Skov; Pedersen, Christian

    2008-10-27

    We report to our best knowledge the first all semiconductor Laser Doppler Anemometer (LIDAR) for wind speed determination. We will present the design and first experimental results on a focusing coherent cw laser Doppler anemometer for measuring atmospheric wind velocities in the 10 meters to 300 meters distance range. Especially, we will demonstrate that both the output power as well as the demanding coherence properties required from the laser source can be accomplished by an all semiconductor laser. Preliminary tests at a distance of 40 meters indicate a typical signal to noise ratio of 9 dB. This result is obtained at a clear day with an up-date rate of 12 Hz.

  16. Laser Doppler anemometer studies in unsteady ventricular flows.

    Science.gov (United States)

    Phillips, W M; Furkay, S S; Pierce, W S

    1979-01-01

    The laser Doppler technique was employed to obtain intraventricular velocity distributions on the basis of in vivo confirmation of previous in vitro flow visualization predictions. The quasi-steady assumption required for quantification of flow visualization results is unsatisfactory in regions of high acceleration and fluctuating velocities are unavailable via such techniques. Mean and fluctuating velocity profiles were obtained in a pneumatically driven prosthetic ventricle with the laser Doppler anemometer and stress levels estimated. The preliminary data presented here illustrates that the technique can be applied to such flows. The measurement and data reduction schemes are applicable to a wide range of simulated cardiovascular flows. The particular application to prosthetic ventricle design should minimize the number of in vivo experiments required to develop a satisfactory blood pump and aid in tailoring pump actuation protocols for minimum thromboembolic complications.

  17. Intercanine width as a tool in two dimensional reconstruction of face: An aid in forensic dentistry.

    Science.gov (United States)

    Shivhare, Peeyush; Shankarnarayan, Lata; Basavaraju, Sowbhagya Malligere; Gupta, Ashish; Vasan, Vinitra; Jambunath, Usha

    2015-01-01

    Dental evidence is a valuable tool in identifying individuals, especially when disasters befall. Reference points in faciomaxillary region such as interpupillary distance, intercanthal distance, interalar distance and bizygomatic width can significantly contribute toward reconstruction of two-dimensional (2D) facial profiles. This study was researched upon to determine the relationship between the maxillary intercanine width and the different reference points of the face. The aim of the following study is to ascertain whether maxillary intercanine width can be used to detect interpupillary distance, intercanthal distance, interalar distance and bizygomatic distance and to evaluate the role of maxillary intercanine width in the 2D reconstruction of the face. The study was carried out by consent and involved 90 subjects-45 males and 45 females who satisfied the inclusion criteria. Subjects were divided into three age groups, i.e. 18-24, 25-28, 29-35. Four parameters were measured- intercanine width, interpupillary distance, intercanthal distance and interalar distance. All the measurements were carried out with a digital Vernier caliper. The bizygomatic width was measured from posterior-anterior view. Two empiricists were assigned for the task. Each test was carried out twice to validate the soundness of the findings and to reduce bias. Analysis of variance and Pearson correlation was established. Regression analysis was performed to predict the study variables by intercanine width. Intercanine width showed a significant relationship with different points. The width varied with age and gender. Inter canine width can be used as a valuable parameter in the reconstruction of face in two dimensional as it shows significant relationship with faciomaxillary reference point such as interpupillary distance, intercanthal distance, interalar distance and bizygomatic width.

  18. Meckel's Diverticulum: Doppler Ultrasound and the tree sign

    International Nuclear Information System (INIS)

    Archila, Cesar Augusto

    2007-01-01

    Mecker's diverticulum is considered the most frequent congenital anomaly of the gastrointestinal tract, affecting 2% of the popular population. Failure of the obliteration of the viteline duct in the embryogenesis age causes this alteration. Abdominal pain, hemorrhage and obstruction are the clinical expression of this entity. The case of a young 16 years old male, with acute abdomen in whom the ultrasound Doppler color tool made the diagnosis of Meckel's diverticulitis is reported. The tree sign: an ultrasonographic sign is illustrated

  19. Aerosol/Cloud Measurements Using Coherent Wind Doppler Lidars

    Directory of Open Access Journals (Sweden)

    Royer Philippe

    2016-01-01

    LEOSPHERE has recently developed aerosol/cloud detection and characterization on WINDCUBE long range Coherent Wind Doppler Lidars (CWDL. These new features combine wind and backscatter intensity informations (Carrier-to-Noise Ratio CNR in order to detect (aerosol/cloud base and top, PBL height and to characterize atmospheric structures (attenuated backscatter, depolarization ratio. For each aerosol/cloud functionality the method is described, limitations are discussed and examples are given to illustrate the performances.

  20. Temperature and Doppler Coefficients of Various Space Nuclear Reactors

    Science.gov (United States)

    Mughabghab, Said F.; Ludewig, Hans; Schmidt, Eldon

    1994-07-01

    Temperature and Doppler feedback effects for a Particle Bed Reactor (PBR) designed to operate as a propulsion reactor are investigated. Several moderator types and compositions fuel enrichments and reactor sizes are considered in this study. From this study it could be concluded that a PBR can be configured which has a negative prompt feedback, zero coolant worth, and a small positive to zero moderator worth. This reactor would put the lowest demands on the control system.