Effects of single antegrade hot shot in comparison with no hot shot administration during coronary artery bypass grafting

Directory of Open Access Journals (Sweden)

Pouya Mirmohammadsadeghi

2015-05-01

Full Text Available BACKGROUND: Superior results will be achieved from cardiac surgery by minimizing the effect of ischemia/reperfusion injury during cross-clamping of the aorta. Different cardioplegia solutions have been introduced, but the optimum one is still ambiguous. The aim of this study is to determine the effect of single antegrade hot shot terminal warm blood cardioplegia (TWBC on patients who had undergone coronary artery bypass grafting (CABG. METHODS: In total, 2488 patients who had CABG surgery in Sina Hospital, Isfahan, Iran, from 2003 to 2011 were enrolled in this case-control study. They were divided into two groups, those who received cold cardioplegia only and those who received a hot shot following cold cardioplegia. Demographics, and clinical data, such as; premature atrial contraction (PAC arrhythmia, diabetes treatment, and left ventricular ejection fraction (EF, were collected and logistic regression analysis was used to analyze the data. RESULTS: There were significant differences found between subjects receiving antegrade hot shot based on direct current (DC shocks, with regard to; female, EF levels, diabetes treatment (P < 0.050. Those who did not receive the hot shot and were not diabetic received more DC shock (P = 0.019. The prevalence of subjects who did no need DC shock was significantly higher among male subjects who had good EF and acceptable diabetic treatment. Multiple logistic regression showed that PAC arrhythmia did not have a significant effect on receiving DC shock during CAGB [0.84 (0.25, 2.85, (P = 0.780]. Having poor EF increased the risk of receiving DC shock among subjects by 2.81 [(1.69, 4.69, (P ≤ 0.001] (P < 0.001. Among the diabetic subjects, receiving insulin decreased the risk of receiving DC shock by 0.54 (0.29, 0.98 (P = 0.042. CONCLUSION: It was concluded that single antegrade hot shot following cold cardioplegia was not particularly effective in the CABG group. TWBC will decrease the need for DC shock.   

Partial Fourier techniques in single-shot cross-term spatiotemporal encoded MRI.

Science.gov (United States)

Zhang, Zhiyong; Frydman, Lucio

2018-03-01

Cross-term spatiotemporal encoding (xSPEN) is a single-shot approach with exceptional immunity to field heterogeneities, the images of which faithfully deliver 2D spatial distributions without requiring a priori information or using postacquisition corrections. xSPEN, however, suffers from signal-to-noise ratio penalties due to its non-Fourier nature and due to diffusion losses-especially when seeking high resolution. This study explores partial Fourier transform approaches that, acting along either the readout or the spatiotemporally encoded dimensions, reduce these penalties. xSPEN uses an orthogonal (e.g., z) gradient to read, in direct space, the low-bandwidth (e.g., y) dimension. This substantially changes the nature of partial Fourier acquisitions vis-à-vis conventional imaging counterparts. A suitable theoretical analysis is derived to implement these procedures, along either the spatiotemporally or readout axes. Partial Fourier single-shot xSPEN images were recorded on preclinical and human scanners. Owing to their reduction in the experiments' acquisition times, this approach provided substantial sensitivity gains vis-à-vis previous implementations for a given targeted in-plane resolution. The physical origins of these gains are explained. Partial Fourier approaches, particularly when implemented along the low-bandwidth spatiotemporal dimension, provide several-fold sensitivity advantages at minimal costs to the execution and processing of the single-shot experiments. Magn Reson Med 79:1506-1514, 2018. © 2017 International Society for Magnetic Resonance in Medicine. © 2017 International Society for Magnetic Resonance in Medicine.

Single-shot spiral imaging enabled by an expanded encoding model: Demonstration in diffusion MRI.

Science.gov (United States)

Wilm, Bertram J; Barmet, Christoph; Gross, Simon; Kasper, Lars; Vannesjo, S Johanna; Haeberlin, Max; Dietrich, Benjamin E; Brunner, David O; Schmid, Thomas; Pruessmann, Klaas P

2017-01-01

The purpose of this work was to improve the quality of single-shot spiral MRI and demonstrate its application for diffusion-weighted imaging. Image formation is based on an expanded encoding model that accounts for dynamic magnetic fields up to third order in space, nonuniform static B 0 , and coil sensitivity encoding. The encoding model is determined by B 0 mapping, sensitivity mapping, and concurrent field monitoring. Reconstruction is performed by iterative inversion of the expanded signal equations. Diffusion-tensor imaging with single-shot spiral readouts is performed in a phantom and in vivo, using a clinical 3T instrument. Image quality is assessed in terms of artefact levels, image congruence, and the influence of the different encoding factors. Using the full encoding model, diffusion-weighted single-shot spiral imaging of high quality is accomplished both in vitro and in vivo. Accounting for actual field dynamics, including higher orders, is found to be critical to suppress blurring, aliasing, and distortion. Enhanced image congruence permitted data fusion and diffusion tensor analysis without coregistration. Use of an expanded signal model largely overcomes the traditional vulnerability of spiral imaging with long readouts. It renders single-shot spirals competitive with echo-planar readouts and thus deploys shorter echo times and superior readout efficiency for diffusion imaging and further prospective applications. Magn Reson Med 77:83-91, 2017. © 2016 International Society for Magnetic Resonance in Medicine. © 2016 International Society for Magnetic Resonance in Medicine.

Single-Shot MR Spectroscopic Imaging with Partial Parallel Imaging

Science.gov (United States)

Posse, Stefan; Otazo, Ricardo; Tsai, Shang-Yueh; Yoshimoto, Akio Ernesto; Lin, Fa-Hsuan

2010-01-01

An MR spectroscopic imaging (MRSI) pulse sequence based on Proton-Echo-Planar-Spectroscopic-Imaging (PEPSI) is introduced that measures 2-dimensional metabolite maps in a single excitation. Echo-planar spatial-spectral encoding was combined with interleaved phase encoding and parallel imaging using SENSE to reconstruct absorption mode spectra. The symmetrical k-space trajectory compensates phase errors due to convolution of spatial and spectral encoding. Single-shot MRSI at short TE was evaluated in phantoms and in vivo on a 3 T whole body scanner equipped with 12-channel array coil. Four-step interleaved phase encoding and 4-fold SENSE acceleration were used to encode a 16×16 spatial matrix with 390 Hz spectral width. Comparison with conventional PEPSI and PEPSI with 4-fold SENSE acceleration demonstrated comparable sensitivity per unit time when taking into account g-factor related noise increases and differences in sampling efficiency. LCModel fitting enabled quantification of Inositol, Choline, Creatine and NAA in vivo with concentration values in the ranges measured with conventional PEPSI and SENSE-accelerated PEPSI. Cramer-Rao lower bounds were comparable to those obtained with conventional SENSE-accelerated PEPSI at the same voxel size and measurement time. This single-shot MRSI method is therefore suitable for applications that require high temporal resolution to monitor temporal dynamics or to reduce sensitivity to tissue movement. PMID:19097245

A single-shot nonlinear autocorrelation approach for time-resolved physics in the vacuum ultraviolet spectral range

International Nuclear Information System (INIS)

Rompotis, Dimitrios

2016-02-01

In this work, a single-shot temporal metrology scheme operating in the vacuum-extreme ultraviolet spectral range has been designed and experimentally implemented. Utilizing an anti-collinear geometry, a second-order intensity autocorrelation measurement of a vacuum ultraviolet pulse can be performed by encoding temporal delay information on the beam propagation coordinate. An ion-imaging time-of-flight spectrometer, offering micrometer resolution has been set-up for this purpose. This instrument enables the detection of a magnified image of the spatial distribution of ions exclusively generated by direct two-photon absorption in the combined counter-propagating pulse focus and thus obtain the second-order intensity autocorrelation measurement on a single-shot basis. Additionally, an intense VUV light source based on high-harmonic generation has been experimentally realized. It delivers intense sub-20 fs Ti:Sa fifth-harmonic pulses utilizing a loose-focusing geometry in a long Ar gas cell. The VUV pulses centered at 161.8 nm reach pulse energies of 1.1 μJ per pulse, while the corresponding pulse duration is measured with a second-order, fringe-resolved autocorrelation scheme to be 18 ± 1 fs on average. Non-resonant, two-photon ionization of Kr and Xe and three-photon ionization of Ne verify the fifth-harmonic pulse intensity and indicate the feasibility of multi-photon VUV pump/VUV probe studies of ultrafast atomic and molecular dynamics. Finally, the extended functionally of the counter-propagating pulse metrology approach is demonstrated by a single-shot VUV pump/VUV probe experiment aiming at the investigation of ultrafast dissociation dynamics of O 2 excited in the Schumann-Runge continuum at 162 nm.

Lead shot from hunting as a source of lead in human blood

International Nuclear Information System (INIS)

Johansen, Poul; Pedersen, Henning Sloth; Asmund, Gert; Riget, Frank

2006-01-01

This study investigates the relationship between the intake of birds hunted with lead shot and the lead concentration in human blood. Fifty adult men from Nuuk, Greenland took part in the study. From September 2003 to June 2004 they regularly gave blood samples and recorded how many birds they ate. We found a clear relationship between the number of bird meals and blood lead and also a clear seasonal variation. The concentration was highest in mid-winter when bird consumption is at its highest. Blood lead was low (15 μg/L, mean concentration) among the participants reporting not eating birds. Among those reporting to eat birds regularly, blood lead was significantly higher, up to 128 μg/L (mean concentration). Concentrations depended on the frequency of bird meals: the more the bird meals, the higher the resulting blood lead. This clear relationship points to lead shot as the dominating lead source to people in Greenland. - Birds hunted with lead shot and consumed are a source of lead in human blood

Lead shot from hunting as a source of lead in human blood

Energy Technology Data Exchange (ETDEWEB)

Johansen, Poul [National Environmental Research Institute, Frederiksborgvej 399, DK-4000 Roskilde (Denmark)]. E-mail: poj@dmu.dk; Pedersen, Henning Sloth [Primary Health Care Center, DK-3900 Nuuk (Greenland); Asmund, Gert [National Environmental Research Institute, Frederiksborgvej 399, DK-4000 Roskilde (Denmark); Riget, Frank [National Environmental Research Institute, Frederiksborgvej 399, DK-4000 Roskilde (Denmark)

2006-07-15

This study investigates the relationship between the intake of birds hunted with lead shot and the lead concentration in human blood. Fifty adult men from Nuuk, Greenland took part in the study. From September 2003 to June 2004 they regularly gave blood samples and recorded how many birds they ate. We found a clear relationship between the number of bird meals and blood lead and also a clear seasonal variation. The concentration was highest in mid-winter when bird consumption is at its highest. Blood lead was low (15 {mu}g/L, mean concentration) among the participants reporting not eating birds. Among those reporting to eat birds regularly, blood lead was significantly higher, up to 128 {mu}g/L (mean concentration). Concentrations depended on the frequency of bird meals: the more the bird meals, the higher the resulting blood lead. This clear relationship points to lead shot as the dominating lead source to people in Greenland. - Birds hunted with lead shot and consumed are a source of lead in human blood.

Infrared single shot diagnostics for the longitudinal profile of the electron bunches at FLASH

International Nuclear Information System (INIS)

Delsim-Hashemi, Hossein

2008-09-01

The longitudinal profile of electron bunches plays an important role in the design of single-pass free electron lasers and future linear e + e - colliders. For the free electron laser FLASH in Hamburg, a longitudinal compression scheme is used which results in an asymmetric longitudinal bunch profile with a 'spike'. This 'spike', which has a very high peak current, is used in a high-gain SASE-FEL process to produce high intensity (about 70 μJ) femtosecond photon pulses in the XUV wavelength range. The required high peak current of the electron bunch is realized by confining a large number of electrons in a width, measured in time units, of few tens of femtosecond, making the diagnostics of such bunches a challenge. Furthermore, the operation of facilities such as FLASH shows that single-shot diagnostics is indispensable. It is intuitive to use a time domain method to measure the electron bunch length. However, when the structures present in the bunch profile fall in the femtoseconds range, this is beyond the resolution of time-resolved methods developed so far. In this thesis, a wavelength-domain technique is described that can fulfill both requirements of single shot and high resolution reaching to the femtoseconds range. The amount of charge that is confined in a typical length of several femtoseconds (FWHM of the spike) can be determined by a novel single-shot spectrometer that resolves the coherent radiation (e.g. coherent transition radiation) in the far-infrared and mid-infrared range. Furthermore the extension of this single-shot spectroscopy to shorter wavelengths reaching the near-infrared, makes it possible to investigate the presence of structures in the bunch profile that might correlate or anti-correlate to the SASE intensity. (orig.)

Infrared single shot diagnostics for the longitudinal profile of the electron bunches at FLASH

Energy Technology Data Exchange (ETDEWEB)

Delsim-Hashemi, Hossein

2008-09-15

The longitudinal profile of electron bunches plays an important role in the design of single-pass free electron lasers and future linear e{sup +}e{sup -} colliders. For the free electron laser FLASH in Hamburg, a longitudinal compression scheme is used which results in an asymmetric longitudinal bunch profile with a 'spike'. This 'spike', which has a very high peak current, is used in a high-gain SASE-FEL process to produce high intensity (about 70 {mu}J) femtosecond photon pulses in the XUV wavelength range. The required high peak current of the electron bunch is realized by confining a large number of electrons in a width, measured in time units, of few tens of femtosecond, making the diagnostics of such bunches a challenge. Furthermore, the operation of facilities such as FLASH shows that single-shot diagnostics is indispensable. It is intuitive to use a time domain method to measure the electron bunch length. However, when the structures present in the bunch profile fall in the femtoseconds range, this is beyond the resolution of time-resolved methods developed so far. In this thesis, a wavelength-domain technique is described that can fulfill both requirements of single shot and high resolution reaching to the femtoseconds range. The amount of charge that is confined in a typical length of several femtoseconds (FWHM of the spike) can be determined by a novel single-shot spectrometer that resolves the coherent radiation (e.g. coherent transition radiation) in the far-infrared and mid-infrared range. Furthermore the extension of this single-shot spectroscopy to shorter wavelengths reaching the near-infrared, makes it possible to investigate the presence of structures in the bunch profile that might correlate or anti-correlate to the SASE intensity. (orig.)

Single-shot LIBS spectral quality for waste particles in open air

NARCIS (Netherlands)

Xia, H.; Bakker, M.C.M.

2015-01-01

This work investigates the ability of LIBS to produce quality spectra from small particles of concrete demolition waste using single-shot spectra collected in open air. The 2–8?mm materials are rounded river gravel, green glass shards, and plastic flakes. Considered are focal length, air, moisture,

Compressive sensing sectional imaging for single-shot in-line self-interference incoherent holography

Science.gov (United States)

Weng, Jiawen; Clark, David C.; Kim, Myung K.

2016-05-01

A numerical reconstruction method based on compressive sensing (CS) for self-interference incoherent digital holography (SIDH) is proposed to achieve sectional imaging by single-shot in-line self-interference incoherent hologram. The sensing operator is built up based on the physical mechanism of SIDH according to CS theory, and a recovery algorithm is employed for image restoration. Numerical simulation and experimental studies employing LEDs as discrete point-sources and resolution targets as extended sources are performed to demonstrate the feasibility and validity of the method. The intensity distribution and the axial resolution along the propagation direction of SIDH by angular spectrum method (ASM) and by CS are discussed. The analysis result shows that compared to ASM the reconstruction by CS can improve the axial resolution of SIDH, and achieve sectional imaging. The proposed method may be useful to 3D analysis of dynamic systems.

Single-shot magnetic resonance spectroscopic imaging with partial parallel imaging.

Science.gov (United States)

Posse, Stefan; Otazo, Ricardo; Tsai, Shang-Yueh; Yoshimoto, Akio Ernesto; Lin, Fa-Hsuan

2009-03-01

A magnetic resonance spectroscopic imaging (MRSI) pulse sequence based on proton-echo-planar-spectroscopic-imaging (PEPSI) is introduced that measures two-dimensional metabolite maps in a single excitation. Echo-planar spatial-spectral encoding was combined with interleaved phase encoding and parallel imaging using SENSE to reconstruct absorption mode spectra. The symmetrical k-space trajectory compensates phase errors due to convolution of spatial and spectral encoding. Single-shot MRSI at short TE was evaluated in phantoms and in vivo on a 3-T whole-body scanner equipped with a 12-channel array coil. Four-step interleaved phase encoding and fourfold SENSE acceleration were used to encode a 16 x 16 spatial matrix with a 390-Hz spectral width. Comparison with conventional PEPSI and PEPSI with fourfold SENSE acceleration demonstrated comparable sensitivity per unit time when taking into account g-factor-related noise increases and differences in sampling efficiency. LCModel fitting enabled quantification of inositol, choline, creatine, and N-acetyl-aspartate (NAA) in vivo with concentration values in the ranges measured with conventional PEPSI and SENSE-accelerated PEPSI. Cramer-Rao lower bounds were comparable to those obtained with conventional SENSE-accelerated PEPSI at the same voxel size and measurement time. This single-shot MRSI method is therefore suitable for applications that require high temporal resolution to monitor temporal dynamics or to reduce sensitivity to tissue movement.

Method for single-shot measurement of picosecond laser pulse-lengths without electronic time dispersion

International Nuclear Information System (INIS)

Kyrala, G.A.

1987-01-01

A two-source shear pattern recording is proposed as a method for single-shot measurement of the pulse shape from nearly monochromatic sources whose pulse lengths are shorter than their coherence times. The basis of this method relies on the assertion that if two identical electromagnetic pulses are recombined with a time delay greater than the sum of their pulse widths, the recordable spatial pattern has no fringes in it. At an arbitrary delay, translated into an actual spatial recording position, the recorded modulated intensity will sample the corresponding laser intensity at that delay time, but with a modulation due to the coherence function of the electromagnetic pulse. Two arrangements are proposed for recording the pattern. The principles, the design parameters, and the methodologies of these arrangements are presented. Resolutions of the configurations and their limitations are given as well

Single-shot echo-planar imaging of multiple sclerosis: effects of varying echo time

International Nuclear Information System (INIS)

Wolansky, L.J.; Chong, S.; Liu, W.C.; Kang, E.; Simpson, S.W.; Karimi, S.; Akbari, H.

1999-01-01

Our aim was to determine the relative merits of short and long echo times (TE) with single-shot echo-planar imaging for imaging cerebral lesions such as multiple sclerosis. We examined seven patients with clinically definite multiple sclerosis were imaged at 1.5 T. Patients were scanned with spin-echo, single-shot echo-planar imaging, using TEs of 45, 75, 105, and 135 ms. Region of interest (ROI) measurements were performed on 36 lesions at or above the level of the corona radiata. The mean image contrast (IC) was highest (231.1) for a TE of 45 ms, followed by 75 ms (218.9), 105 ms (217.9), and 135 ms (191.6). When mean contrast-to-noise ratios (C/N) were compared, the value was again highest (29.7) for TE 45 ms, followed by 75 ms (28.9), 105 ms (28.5), and 135 ms (26.3). In a lesion-by-lesion comparison, TE 45 ms had the highest IC and C/N in the largest number of cases (50 % and 47.2 %, respectively). IC and C/N for TE 45 ms were superior to those of 75 ms in 64 % and 58 %, respectively. These results support the use of relatively short TEs for single-shot echo-planar imaging in the setting of cerebral lesions such as multiple sclerosis. (orig.) (orig.)

Single-shot 35 fs temporal resolution electron shadowgraphy

Energy Technology Data Exchange (ETDEWEB)

Scoby, C. M.; Li, R. K.; Threlkeld, E.; To, H.; Musumeci, P. [Department of Physics and Astronomy, UCLA, Los Angeles, California 90095 (United States)

2013-01-14

We obtain single-shot time-resolved shadowgraph images of the electromagnetic fields resulting from the interaction of a high intensity ultrashort laser pulse with a metal surface. Using a high brightness relativistic electron beam and a high streaking speed radiofrequency deflector, we report <35 fs temporal resolution enabling a direct visualization of the retarded-time dominated field evolution which follows the laser-induced charge emission. A model including the finite signal propagation speed well reproduces the data and yields measurements of fundamental parameters in short pulse laser-matter interaction such as the amount of emitted charge and the emission time scale.

Single-shot 35 fs temporal resolution electron shadowgraphy

International Nuclear Information System (INIS)

Scoby, C. M.; Li, R. K.; Threlkeld, E.; To, H.; Musumeci, P.

2013-01-01

We obtain single-shot time-resolved shadowgraph images of the electromagnetic fields resulting from the interaction of a high intensity ultrashort laser pulse with a metal surface. Using a high brightness relativistic electron beam and a high streaking speed radiofrequency deflector, we report <35 fs temporal resolution enabling a direct visualization of the retarded-time dominated field evolution which follows the laser-induced charge emission. A model including the finite signal propagation speed well reproduces the data and yields measurements of fundamental parameters in short pulse laser-matter interaction such as the amount of emitted charge and the emission time scale.

Single-shot positron annihilation lifetime spectroscopy with LYSO scintillators

OpenAIRE

Alonso, A. M.; Cooper, B. S.; Deller, A.; Cassidy, D. B.

2016-01-01

We have evaluated the application of a lutetium yttrium oxyorthosilicate (LYSO) based detector to single-shot positron annihilation lifetime spectroscopy. We compare this detector directly with a similarly configured PbWO4 scintillator, which is the usual choice for such measurements. We find that the signal to noise ratio obtained using LYSO is around three times higher than that obtained using PbWO4 for measurements of Ps excited to longer-lived (Rydberg) levels, or when they are ionized so...

Single-shot and single-spot measurement of laser ablation threshold for carbon nanotubes

International Nuclear Information System (INIS)

Lednev, Vasily N; Pershin, Sergey M; Bunkin, Alexey F; Obraztsova, Elena D; Kudryashov, Sergey I

2013-01-01

A simple and convenient procedure for single-shot, single-spot ablation threshold measurement is developed. It is based on the employment of cylindrical lens to obtain an elliptical Gaussian laser spot. The ablated spot chords that are parallel to the minor axis are measured across the spot major axis, which is proportional to the fluence cross-section, thus providing wide range dependence of damaged spot size versus fluence in one spot measurement. For both conventional and newly developed procedures the ablation threshold for typical Nd:YAG laser parameters (1064 nm, 10 ns) is measured as 50 ± 5 mJ cm -2 , which is one order of magnitude lower than that for bulk graphite.

Single-shot imaging with higher-dimensional encoding using magnetic field monitoring and concomitant field correction.

Science.gov (United States)

Testud, Frederik; Gallichan, Daniel; Layton, Kelvin J; Barmet, Christoph; Welz, Anna M; Dewdney, Andrew; Cocosco, Chris A; Pruessmann, Klaas P; Hennig, Jürgen; Zaitsev, Maxim

2015-03-01

PatLoc (Parallel Imaging Technique using Localized Gradients) accelerates imaging and introduces a resolution variation across the field-of-view. Higher-dimensional encoding employs more spatial encoding magnetic fields (SEMs) than the corresponding image dimensionality requires, e.g. by applying two quadratic and two linear spatial encoding magnetic fields to reconstruct a 2D image. Images acquired with higher-dimensional single-shot trajectories can exhibit strong artifacts and geometric distortions. In this work, the source of these artifacts is analyzed and a reliable correction strategy is derived. A dynamic field camera was built for encoding field calibration. Concomitant fields of linear and nonlinear spatial encoding magnetic fields were analyzed. A combined basis consisting of spherical harmonics and concomitant terms was proposed and used for encoding field calibration and image reconstruction. A good agreement between the analytical solution for the concomitant fields and the magnetic field simulations of the custom-built PatLoc SEM coil was observed. Substantial image quality improvements were obtained using a dynamic field camera for encoding field calibration combined with the proposed combined basis. The importance of trajectory calibration for single-shot higher-dimensional encoding is demonstrated using the combined basis including spherical harmonics and concomitant terms, which treats the concomitant fields as an integral part of the encoding. © 2014 Wiley Periodicals, Inc.

Single-shot readout of accumulation mode Si/SiGe spin qubits using RF reflectometry

Science.gov (United States)

Volk, Christian; Martins, Frederico; Malinowski, Filip; Marcus, Charles M.; Kuemmeth, Ferdinand

Spin qubits based on gate-defined quantum dots are promising systems for realizing quantum computation. Due to their low concentration of nuclear-spin-carrying isotopes, Si/SiGe heterostructures are of particular interest. While high fidelities have been reported for single-qubit and two-qubit gate operations, qubit initialization and measurement times are relatively slow. In order to develop fast read-out techniques compatible with the operation of spin qubits, we characterize double and triple quantum dots confined in undoped Si/Si0.7Ge0.3 heterostructures using accumulation and depletion gates and a nearby RF charge sensor dot. We implement a RF reflectometry technique that allows single-shot charge read-out at integration times on the order of a few μs. We show our recent advancement towards implementing spin qubits in these structures, including spin-selective single-shot read-out.

Geochemistry of Eagle Ford group source rocks and oils from the first shot field area, Texas

Science.gov (United States)

Edman, Janell D.; Pitman, Janet K.; Hammes, Ursula

2010-01-01

Total organic carbon, Rock-Eval pyrolysis, and vitrinite reflectance analyses performed on Eagle Ford Group core and cuttings samples from the First Shot field area, Texas demonstrate these samples have sufficient quantity, quality, and maturity of organic matter to have generated oil. Furthermore, gas chromatography and biomarker analyses performed on Eagle Ford Group oils and source rock extracts as well as weight percent sulfur analyses on the oils indicate the source rock facies for most of the oils are fairly similar. Specifically, these source rock facies vary in lithology from shales to marls, contain elevated levels of sulfur, and were deposited in a marine environment under anoxic conditions. It is these First Shot Eagle Ford source facies that have generated the oils in the First Shot Field. However, in contrast to the generally similar source rock facies and organic matter, maturity varies from early oil window to late oil window in the study area, and these maturity variations have a pronounced effect on both the source rock and oil characteristics. Finally, most of the oils appear to have been generated locally and have not experienced long distance migration. 

Shot noise as a probe of spin-polarized transport through single atoms

DEFF Research Database (Denmark)

Burtzlaff, Andreas; Weismann, Alexander; Brandbyge, Mads

2015-01-01

Single atoms on Au(111) surfaces have been contacted with the Au tip of a low temperature scanning tunneling microscope. The shot noise of the current through these contacts has been measured up to frequencies of 120 kHz and Fano factors have been determined to characterize the transport channels...

Single-shot fluctuations in waveguided high-harmonic generation

NARCIS (Netherlands)

Goh, S.J.; Tao, Y.; van der Slot, Petrus J.M.; Bastiaens, Hubertus M.J.; Herek, Jennifer Lynn; Biedron, S.G.; Danailov, M.B.; Milton, S.V.; Boller, Klaus J.

2015-01-01

For exploring the application potential of coherent soft x-ray (SXR) and extreme ultraviolet radiation (XUV) provided by high-harmonic generation, it is important to characterize the central output parameters. Of specific importance are pulse-to-pulse (shot-to-shot) fluctuations of the high-harmonic

Hyperspectral interferometry for single-shot absolute measurement of 3-D shape and displacement fields

Directory of Open Access Journals (Sweden)

Ruiz P. D.

2010-06-01

Full Text Available We propose a method that we call Hyperspectral Interferometry (HSI to resolve the 2π phase unwrapping problem in the analysis of interferograms recorded with a narrow-band light source. By using a broad-band light source and hyperspectral imaging system, a set of interferograms at different wavenumbers are recorded simultaneously on a high resolution image sensor. These are then assembled to form a three-dimensional intensity distribution. By Fourier transformation along the wavenumber axis, an absolute optical path difference is obtained for each pixel independently of the other pixels in the field of view. As a result, interferograms with spatially distinct regions are analysed as easily as continuous ones. The approach is illustrated with a HSI system to measure 3-D profiles of optically smooth or rough surfaces. Compared to existing profilometers able to measure absolute path differences, the single shot nature of the approach provides greater immunity from environmental disturbance.

Ultrafast bold fMRI using single-shot spin-echo echo planar imaging

Directory of Open Access Journals (Sweden)

Boujraf Said

2009-01-01

Full Text Available The choice of imaging parameters for functional MRI can have an impact on the accuracy of functional localization by affecting the image quality and the degree of blood oxygenation-dependent (BOLD contrast achieved. By improving sampling efficiency, parallel acquisition techniques such as sensitivity encoding (SENSE have been used to shorten readout trains in single-shot (SS echo planar imaging (EPI. This has been applied to susceptibility artifact reduction and improving spatial resolution. SENSE together with single-shot spin-echo (SS-SE imaging may also reduce off-resonance artifacts. The goal of this work was to investigate the BOLD response of a SENSE-adapted SE-EPI on a three Tesla scanner. Whole-brain fMRI studies of seven healthy right hand-dominant volunteers were carried out in a three Tesla scanner. fMRI was performed using an SS-SE EPI sequence with SENSE. The data was processed using statistical parametric mapping. Both, group and individual subject data analyses were performed. Individual average percentage and maximal percentage signal changes attributed to the BOLD effect in M1 were calculated for all the subjects as a function of echo time. Corresponding activation maps and the sizes of the activated clusters were also calculated. Our results show that susceptibility artifacts were reduced with the use of SENSE; and the acquired BOLD images were free of the typical quadrature artifacts of SS-EPI. Such measures are crucial at high field strengths. SS SE-EPI with SENSE offers further benefits in this regard and is more specific for oxygenation changes in the microvasculature bed. Functional brain activity can be investigated with the help of single-shot spin echo EPI using SENSE at high magnetic fields.

Algorithms for image recovery calculation in extended single-shot phase-shifting digital holography

Science.gov (United States)

Hasegawa, Shin-ya; Hirata, Ryo

2018-04-01

The single-shot phase-shifting method of image recovery using an inclined reference wave has the advantages of reducing the effects of vibration, being capable of operating in real time, and affording low-cost sensing. In this method, relatively low reference angles compared with that in the conventional method using phase shift between three or four pixels has been required. We propose an extended single-shot phase-shifting technique which uses the multiple-step phase-shifting algorithm and the corresponding multiple pixels which are the same as that of the period of an interference fringe. We have verified the theory underlying this recovery method by means of Fourier spectral analysis and its effectiveness by evaluating the visibility of the image using a high-resolution pattern. Finally, we have demonstrated high-contrast image recovery experimentally using a resolution chart. This method can be used in a variety of applications such as color holographic interferometry.

Single-shot speckle reduction in numerical reconstruction of digitally recorded holograms.

Science.gov (United States)

Hincapie, Diego; Herrera-Ramírez, Jorge; Garcia-Sucerquia, Jorge

2015-04-15

A single-shot method to reduce the speckle noise in the numerical reconstructions of electronically recorded holograms is presented. A recorded hologram with the dimensions N×M is split into S=T×T sub-holograms. The uncorrelated superposition of the individually reconstructed sub-holograms leads to an image with the speckle noise reduced proportionally to the 1/S law. The experimental results are presented to support the proposed methodology.

Strategies to improve phase-stability of ultrafast swept source optical coherence tomography for single shot imaging of transient mechanical waves at 16 kHz frame rate

Energy Technology Data Exchange (ETDEWEB)

Song, Shaozhen; Wei, Wei; Hsieh, Bao-Yu; Pelivanov, Ivan; O' Donnell, Matthew [Department of Bioengineering, University of Washington, Seattle, Washington 98195 (United States); Shen, Tueng T.; Wang, Ruikang K., E-mail: wangrk@uw.edu [Department of Bioengineering, University of Washington, Seattle, Washington 98195 (United States); Department of Ophthalmology, University of Washington, Seattle, Washington 98104 (United States)

2016-05-09

We present single-shot phase-sensitive imaging of propagating mechanical waves within tissue, enabled by an ultrafast optical coherence tomography (OCT) system powered by a 1.628 MHz Fourier domain mode-locked (FDML) swept laser source. We propose a practical strategy for phase-sensitive measurement by comparing the phases between adjacent OCT B-scans, where the B-scan contains a number of A-scans equaling an integer number of FDML buffers. With this approach, we show that micro-strain fields can be mapped with ∼3.0 nm sensitivity at ∼16 000 fps. The system's capabilities are demonstrated on porcine cornea by imaging mechanical wave propagation launched by a pulsed UV laser beam, promising non-contact, real-time, and high-resolution optical coherence elastography.

Ultrafast T2-weighted single shot spin-echo sequences: applications on abdominal and pelvic pathologies

International Nuclear Information System (INIS)

Martin, J.; Martin, C.; Falco, J.; Esteban, L.

1999-01-01

The magnetic resonance imaging (MRI) sequences that obtain all the data using a sole excitation pulse of 90 degree centigrade, filling the K space in a single repetition time (TR) is known as snap shot or single shot (SS). The SS sequence based on the rapid acquisition with relaxation enhancement (SS-RARE) method, designed by Hening (1) and a variation of it with a half-Fourier reconstruction (SS-HF-RARE (HASTEL)) (2, 3) are capable of obtaining high contrast images in T2, in very short times, that oscillate between one to several seconds. The clinical application of these sequences to abdominal and pelvic pathologies is increasing, providing and improvement in the contrast resolution, but also in the spatial resolution, with a high relation signal/noise ratio, high contrast and absence of movement artifacts. (Author)

Multishot versus single-shot pulse sequences in very high field fMRI: a comparison using retinotopic mapping.

Directory of Open Access Journals (Sweden)

Jascha D Swisher

Full Text Available High-resolution functional MRI is a leading application for very high field (7 Tesla human MR imaging. Though higher field strengths promise improvements in signal-to-noise ratios (SNR and BOLD contrast relative to fMRI at 3 Tesla, these benefits may be partially offset by accompanying increases in geometric distortion and other off-resonance effects. Such effects may be especially pronounced with the single-shot EPI pulse sequences typically used for fMRI at standard field strengths. As an alternative, one might consider multishot pulse sequences, which may lead to somewhat lower temporal SNR than standard EPI, but which are also often substantially less susceptible to off-resonance effects. Here we consider retinotopic mapping of human visual cortex as a practical test case by which to compare examples of these sequence types for high-resolution fMRI at 7 Tesla. We performed polar angle retinotopic mapping at each of 3 isotropic resolutions (2.0, 1.7, and 1.1 mm using both accelerated single-shot 2D EPI and accelerated multishot 3D gradient-echo pulse sequences. We found that single-shot EPI indeed led to greater temporal SNR and contrast-to-noise ratios (CNR than the multishot sequences. However, additional distortion correction in postprocessing was required in order to fully realize these advantages, particularly at higher resolutions. The retinotopic maps produced by both sequence types were qualitatively comparable, and showed equivalent test/retest reliability. Thus, when surface-based analyses are planned, or in other circumstances where geometric distortion is of particular concern, multishot pulse sequences could provide a viable alternative to single-shot EPI.

Clinical evaluation of single-shot and readout-segmented diffusion-weighted imaging in stroke patients at 3 T

International Nuclear Information System (INIS)

Morelli, John; Porter, David; Ai, Fei

2013-01-01

Background: Diffusion-weighted imaging (DWI) magnetic resonance imaging (MRI) is most commonly performed utilizing a single-shot echo-planar imaging technique (ss-EPI). Susceptibility artifact and image blur are severe when this sequence is utilized at 3 T. Purpose: To evaluate a readout-segmented approach to DWI MR in comparison with single-shot echo planar imaging for brain MRI. Material and Methods: Eleven healthy volunteers and 14 patients with acute and early subacute infarctions underwent DWI MR examinations at 1.5 and 3T with ss-EPI and readout-segmented echo-planar (rs-EPI) DWI at equal nominal spatial resolutions. Signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) calculations were made, and two blinded readers ranked the scans in terms of high signal intensity bulk susceptibility artifact, spatial distortions, image blur, overall preference, and motion artifact. Results: SNR and CNR were greatest with rs-EPI (8.1 ± 0.2 SNR vs. 6.0 ± 0.2; P -4 at 3T). Spatial distortions were greater with single-shot (0.23 ± 0.03 at 3T; P <0.001) than with rs-EPI (0.12 ± 0.02 at 3T). Combined with blur and artifact reduction, this resulted in a qualitative preference for the readout-segmented scans overall. Conclusion: Substantial image quality improvements are possible with readout-segmented vs. single-shot EPI - the current clinical standard for DWI - regardless of field strength (1.5 or 3 T). This results in improved image quality secondary to greater real spatial resolution and reduced artifacts from susceptibility in MR imaging of the brain

Radiography simulation on single-shot dual-spectrum X-ray for cargo inspection system

International Nuclear Information System (INIS)

Gil, Youngmi; Oh, Youngdo; Cho, Moohyun; Namkung, Won

2011-01-01

We propose a method to identify materials in the dual energy X-ray (DeX) inspection system. This method identifies materials by combining information on the relative proportions T of high-energy and low-energy X-rays transmitted through the material, and the ratio R of the attenuation coefficient of the material when high-energy are used to that when low energy X-rays are used. In Monte Carlo N-Particle Transport Code (MCNPX) simulations using the same geometry as that of the real container inspection system, this T vs. R method successfully identified tissue-equivalent plastic and several metals. In further simulations, the single-shot mode of operating the accelerator led to better distinguishing of materials than the dual-shot system.

High quality single shot diffraction patterns using ultrashort megaelectron volt electron beams from a radio frequency photoinjector

Energy Technology Data Exchange (ETDEWEB)

Musumeci, P.; Moody, J. T.; Scoby, C. M.; Gutierrez, M. S. [Department of Physics and Astronomy, UCLA, Los Angeles, California 90095 (United States); Bender, H. A.; Wilcox, N. S. [National Security Technologies, LLC, Los Alamos Operations, Los Alamos, New Mexico 87544 (United States)

2010-01-15

Single shot diffraction patterns using a 250-fs-long electron beam have been obtained at the UCLA Pegasus laboratory. High quality images with spatial resolution sufficient to distinguish closely spaced peaks in the Debye-Scherrer ring pattern have been recorded by scattering the 1.6 pC 3.5 MeV electron beam generated in the rf photoinjector off a 100-nm-thick Au foil. Dark current and high emittance particles are removed from the beam before sending it onto the diffraction target using a 1 mm diameter collimating hole. These results open the door to the study of irreversible phase transformations by single shot MeV electron diffraction.

High quality single shot diffraction patterns using ultrashort megaelectron volt electron beams from a radio frequency photoinjector.

Science.gov (United States)

Musumeci, P; Moody, J T; Scoby, C M; Gutierrez, M S; Bender, H A; Wilcox, N S

2010-01-01

Single shot diffraction patterns using a 250-fs-long electron beam have been obtained at the UCLA Pegasus laboratory. High quality images with spatial resolution sufficient to distinguish closely spaced peaks in the Debye-Scherrer ring pattern have been recorded by scattering the 1.6 pC 3.5 MeV electron beam generated in the rf photoinjector off a 100-nm-thick Au foil. Dark current and high emittance particles are removed from the beam before sending it onto the diffraction target using a 1 mm diameter collimating hole. These results open the door to the study of irreversible phase transformations by single shot MeV electron diffraction.

High quality single shot diffraction patterns using ultrashort megaelectron volt electron beams from a radio frequency photoinjector

International Nuclear Information System (INIS)

Musumeci, P.; Moody, J. T.; Scoby, C. M.; Gutierrez, M. S.; Bender, H. A.; Wilcox, N. S.

2010-01-01

Single shot diffraction patterns using a 250-fs-long electron beam have been obtained at the UCLA Pegasus laboratory. High quality images with spatial resolution sufficient to distinguish closely spaced peaks in the Debye-Scherrer ring pattern have been recorded by scattering the 1.6 pC 3.5 MeV electron beam generated in the rf photoinjector off a 100-nm-thick Au foil. Dark current and high emittance particles are removed from the beam before sending it onto the diffraction target using a 1 mm diameter collimating hole. These results open the door to the study of irreversible phase transformations by single shot MeV electron diffraction.

Single-shot beam size measurements using visible-light interferometry at CESR

Energy Technology Data Exchange (ETDEWEB)

Wang, S.T., E-mail: sw565@cornell.edu [Cornell Laboratory for Accelerator-based Science and Education, Cornell University, Ithaca, NY 14853 (United States); Holtzapple, R. [Physics Department, California Polytechnic State University, San Luis Obispo, CA 93407 (United States); Rubin, D.L. [Cornell Laboratory for Accelerator-based Science and Education, Cornell University, Ithaca, NY 14853 (United States)

2017-03-01

A new primary mirror for a visible-light beam size monitor (vBSM) was designed and installed in the Cornell Electron-Positron Storage Ring (CESR). The vertical angular acceptance of the mirror was doubled to allow double-slit interferometry with large slit separation (>12 mm). In addition, the diffraction associated with the first generation mirror has been eliminated. The resolution of the vertical beam size measurements has been dramatically improved but is ultimately limited by the beam motion. Two fast-response detectors, a Photomultiplier Tube (PMT) array and a gated camera, were employed to study the beam motion. The advantages and limitations of both devices are discussed in this paper. The gated camera was also used to measure single-shot beam width and motion of each bunch in a multi-bunch train. We measured significantly more horizontal motion of electron as compared to positron bunch trains in otherwise identical machine condition. This difference may be a signature for the difference between electron cloud build-up for positron bunch trains versus ions effects characteristic of electron bunch trains. - Highlights: • A new extraction mirror for synchrotron radiation was designed and installed in CESR. • The sensitivity of interferometer was increased and the diffraction effect was eliminated. • Two fast-response detectors were employed to study the effect of beam motion. • First time single-shot bunch-by-bunch horizontal beam size measurements using interferometry was observed from gated camera. • The difference in single bunch horizontal dynamics was observed between a positron and an electron train.

Fourier Analysis of Single-Shot Dual-Energy X-ray Imaging Characteristics

International Nuclear Information System (INIS)

Kim, Jun Woo; Kim, Dong Woon; Kim, Ho Kyung

2016-01-01

The sandwich detector was realized by stacking two scintillator-based flat-panel detectors (FPDs) between which an intermediate copper (Cu) filter layer was placed to further enhance spectral energy separation. As a result, the proper selection of filter material and its thickness could be a trade-off between the extent of energy separation (hence, DE image quality) and image noise due to reduction in the number of x-ray quanta reaching the rear FPD. Although the conventional kVp-switching dual-shot method showed better image qualities than the single-shot method because of larger spectral energy separation, the motion-artifact-free DE image with reasonably good image quality was a potential prospect of the single-shot method. For the reliable and better use of the sandwich detector for specific imaging applications, the sandwich detector should be optimally designed with a proper selection of scintillator material and thickness in each detector layer (i.e. the front and rear detectors), and aforementioned intermediate filter material and thickness. It is noted that glue is used to adhere the fragile photodiode array onto the ceramic substrate and these glue patterns are apparent in the rear and DE images. The glue pattern in the rear image comes from the front FPD. Unlike the conventional ESF as shown in Fig. 3(a), the ESF obtained from the subtracted image showed an enhancement as shown in Fig. 3(b). Consequently, the MTF obtained from the subtraction ESF showed a bandpass filter characteristic, as shown in Fig. 3(c), unlike the conventional low-pass filter characteristic (i.e., monotonic decrease of MTF value with increasing the spatial frequency). This MTF characteristic is due to the subtraction of two images with different spatial resolving powers (i.e., different thicknesses of phosphors between the front and rear detectors) as can be seen in unsharp masking digital image processing, which subtracts Gaussian-blurred image from the original image

Fourier Analysis of Single-Shot Dual-Energy X-ray Imaging Characteristics

Energy Technology Data Exchange (ETDEWEB)

Kim, Jun Woo; Kim, Dong Woon; Kim, Ho Kyung [Pusan National University, Busan (Korea, Republic of)

2016-05-15

The sandwich detector was realized by stacking two scintillator-based flat-panel detectors (FPDs) between which an intermediate copper (Cu) filter layer was placed to further enhance spectral energy separation. As a result, the proper selection of filter material and its thickness could be a trade-off between the extent of energy separation (hence, DE image quality) and image noise due to reduction in the number of x-ray quanta reaching the rear FPD. Although the conventional kVp-switching dual-shot method showed better image qualities than the single-shot method because of larger spectral energy separation, the motion-artifact-free DE image with reasonably good image quality was a potential prospect of the single-shot method. For the reliable and better use of the sandwich detector for specific imaging applications, the sandwich detector should be optimally designed with a proper selection of scintillator material and thickness in each detector layer (i.e. the front and rear detectors), and aforementioned intermediate filter material and thickness. It is noted that glue is used to adhere the fragile photodiode array onto the ceramic substrate and these glue patterns are apparent in the rear and DE images. The glue pattern in the rear image comes from the front FPD. Unlike the conventional ESF as shown in Fig. 3(a), the ESF obtained from the subtracted image showed an enhancement as shown in Fig. 3(b). Consequently, the MTF obtained from the subtraction ESF showed a bandpass filter characteristic, as shown in Fig. 3(c), unlike the conventional low-pass filter characteristic (i.e., monotonic decrease of MTF value with increasing the spatial frequency). This MTF characteristic is due to the subtraction of two images with different spatial resolving powers (i.e., different thicknesses of phosphors between the front and rear detectors) as can be seen in unsharp masking digital image processing, which subtracts Gaussian-blurred image from the original image.

Development and Characterization of Two-Dimensional Gratings for Single-Shot X-ray Phase-Contrast Imaging

Directory of Open Access Journals (Sweden)

Margarita Zakharova

2018-03-01

Full Text Available Single-shot grating-based phase-contrast imaging techniques offer additional contrast modalities based on the refraction and scattering of X-rays in a robust and versatile configuration. The utilization of a single optical element is possible in such methods, allowing the shortening of the acquisition time and increasing flux efficiency. One of the ways to upgrade single-shot imaging techniques is to utilize customized optical components, such as two-dimensional (2D X-ray gratings. In this contribution, we present the achievements in the development of 2D gratings with UV lithography and gold electroplating. Absorption gratings represented by periodic free-standing gold pillars with lateral structure sizes from 5 µm to 25 µm and heights from 5 µm to 28 µm have shown a high degree of periodicity and defect-free patterns. Grating performance was tested in a radiographic setup using a self-developed quality assessment algorithm based on the intensity distribution histograms. The algorithm allows the final user to estimate the suitability of a specific grating to be used in a particular setup.

Frequency-Domain Tomography for Single-shot, Ultrafast Imaging of Evolving Laser-Plasma Accelerators

Science.gov (United States)

Li, Zhengyan; Zgadzaj, Rafal; Wang, Xiaoming; Downer, Michael

2011-10-01

Intense laser pulses propagating through plasma create plasma wakefields that often evolve significantly, e.g. by expanding and contracting. However, such dynamics are known in detail only through intensive simulations. Laboratory visualization of evolving plasma wakes in the ``bubble'' regime is important for optimizing and scaling laser-plasma accelerators. Recently snap-shots of quasi-static wakes were recorded using frequency-domain holography (FDH). To visualize the wake's evolution, we have generalized FDH to frequency-domain tomography (FDT), which uses multiple probes propagating at different angles with respect to the pump pulse. Each probe records a phase streak, imprinting a partial record of the evolution of pump-created structures. We then topographically reconstruct the full evolution from all phase streaks. To prove the concept, a prototype experiment visualizing nonlinear index evolution in glass is demonstrated. Four probes propagating at 0, 0.6, 2, 14 degrees to the index ``bubble'' are angularly and temporally multiplexed to a single spectrometer to achieve cost-effective FDT. From these four phase streaks, an FDT algorithm analogous to conventional CT yields a single-shot movie of the pump's self-focusing dynamics.

Research of shot noise based on realistic nano-MOSFETs

Directory of Open Access Journals (Sweden)

Xiaofei Jia

2017-05-01

Full Text Available Experimental measurements and simulation results have shown that the dominant noise source of current noise changes from thermal noise to shot noise with scaling of MOSFET, and shot noise were suppressed by Fermi and Coulomb interactions. In this paper, Shot noise test system is established, and experimental results proved that shot noise were suppressed, and the expressions of shot noise in realistic nano-MOSFETs are derived with considering Fermi effect, Coulomb interaction and the combination of the both co-existence, respectively. On this basis, the variation of shot noise with voltage, temperature and source-drain doping were researched. The results we obtained are consistent with those from experiments and the theoretically explanation is given. At the same time, the shot noise test system is suitable for traditional nanoscale electronic components; the shot noise model is suitable for nanoscale MOSFET.

Will leaded young mallards take wing? Effects of a single lead shot ingestion on growth of juvenile game-farm Mallard ducks Anas platyrhynchos

International Nuclear Information System (INIS)

Plouzeau, Eric; Guillard, Olivier; Pineau, Alain; Billiald, Philippe; Berny, Philippe

2011-01-01

This study aims to monitor retention of a single ingested lead shot in young mallards, and to evaluate effect on growth in relation to lead shot size class during late wing growth and the first wing molt period (8 to 12 weeks old). Toxicological tests, radiography and biometric measurements were conducted on 51 juvenile Mallard ducks. Forty one of them were given per os a single lead shot in three different commercially available sizes: No. 2 (LS2), No. 4 (LS4) and No. 6 (LS6). Less than 20% of total lead shots were found on X-rays at Day 21 (D) and none remained at D28, with mean retention time in gizzard calculated 12.85 ± 1.34 days for all treated groups. Young ducks developed high blood lead levels for each LS treatment at D15 in males and females, the maximal values being for LS2 (297.00 ± 78.64 μg/100 mL and 483.14 ± 83.70 μg/100 mL, respectively (p < 0.001)). Zinc protoporphyrin (ZPP) levels increased at D15 with LS2 and LS4 in males and only with LS6 in females. Treated ducks developed no symptoms of plumbism except light diarrhea, and at D40, all mallards had survived. We found that LS2 pellets released more lead in gizzards and produced the highest levels of blood lead, suggesting that LS2 pellets are more likely to intoxicate mallards than smaller sizes. The biometric measurements performed showed no statistical difference in weight or bill and wing length between control and treated groups, a finding suggesting that absorption of a single lead shot by young Mallard ducks does not affect their development during the first wing molt period, and appears not to compromise the flight capacity of young (post-juvenile) mallards. However, younger mallards and/or effects on growth of exposure to more than a single-shot dose still need to be investigated. - Research highlights: → The mean lead shot retention time in the digestive tract is shorter than expected. → The lead intoxication at D15 and D30 is confirmed in all mallards. → Size-class no. 2 lead

Will leaded young mallards take wing? Effects of a single lead shot ingestion on growth of juvenile game-farm Mallard ducks Anas platyrhynchos

Energy Technology Data Exchange (ETDEWEB)

Plouzeau, Eric, E-mail: biozones@orange.fr [Museum National d' Histoire Naturelle, USM505 Ecosystemes et interactions toxiques, 12 rue Buffon, CP39, Paris Cedex 05 (France); Guillard, Olivier, E-mail: o.guillard@chu-poitiers.fr [CHU Poitiers, Laboratoire de biochimie 86021 Poitiers (France); Pineau, Alain, E-mail: alain.pineau@univ-nantes.fr [Universite Nantes, Faculte de Pharmacie, Laboratoire de Toxicologie 44000 Nantes (France); Billiald, Philippe, E-mail: billiald@mnhn.fr [Museum National d' Histoire Naturelle, USM505 Ecosystemes et interactions toxiques, 12 rue Buffon, CP39, Paris Cedex 05 (France); Berny, Philippe, E-mail: p.berny@vetagro-sup.fr [Laboratoire de Toxicologie, Ecole Nationale Veterinaire de Lyon, BP 83, 69280 Marcy L' Etoile (France)

2011-05-15

This study aims to monitor retention of a single ingested lead shot in young mallards, and to evaluate effect on growth in relation to lead shot size class during late wing growth and the first wing molt period (8 to 12 weeks old). Toxicological tests, radiography and biometric measurements were conducted on 51 juvenile Mallard ducks. Forty one of them were given per os a single lead shot in three different commercially available sizes: No. 2 (LS2), No. 4 (LS4) and No. 6 (LS6). Less than 20% of total lead shots were found on X-rays at Day 21 (D) and none remained at D28, with mean retention time in gizzard calculated 12.85 {+-} 1.34 days for all treated groups. Young ducks developed high blood lead levels for each LS treatment at D15 in males and females, the maximal values being for LS2 (297.00 {+-} 78.64 {mu}g/100 mL and 483.14 {+-} 83.70 {mu}g/100 mL, respectively (p < 0.001)). Zinc protoporphyrin (ZPP) levels increased at D15 with LS2 and LS4 in males and only with LS6 in females. Treated ducks developed no symptoms of plumbism except light diarrhea, and at D40, all mallards had survived. We found that LS2 pellets released more lead in gizzards and produced the highest levels of blood lead, suggesting that LS2 pellets are more likely to intoxicate mallards than smaller sizes. The biometric measurements performed showed no statistical difference in weight or bill and wing length between control and treated groups, a finding suggesting that absorption of a single lead shot by young Mallard ducks does not affect their development during the first wing molt period, and appears not to compromise the flight capacity of young (post-juvenile) mallards. However, younger mallards and/or effects on growth of exposure to more than a single-shot dose still need to be investigated. - Research highlights: {yields} The mean lead shot retention time in the digestive tract is shorter than expected. {yields} The lead intoxication at D15 and D30 is confirmed in all mallards

Single shot trajectory design for region-specific imaging using linear and nonlinear magnetic encoding fields.

Science.gov (United States)

Layton, Kelvin J; Gallichan, Daniel; Testud, Frederik; Cocosco, Chris A; Welz, Anna M; Barmet, Christoph; Pruessmann, Klaas P; Hennig, Jürgen; Zaitsev, Maxim

2013-09-01

It has recently been demonstrated that nonlinear encoding fields result in a spatially varying resolution. This work develops an automated procedure to design single-shot trajectories that create a local resolution improvement in a region of interest. The technique is based on the design of optimized local k-space trajectories and can be applied to arbitrary hardware configurations that employ any number of linear and nonlinear encoding fields. The trajectories designed in this work are tested with the currently available hardware setup consisting of three standard linear gradients and two quadrupolar encoding fields generated from a custom-built gradient insert. A field camera is used to measure the actual encoding trajectories up to third-order terms, enabling accurate reconstructions of these demanding single-shot trajectories, although the eddy current and concomitant field terms of the gradient insert have not been completely characterized. The local resolution improvement is demonstrated in phantom and in vivo experiments. Copyright © 2012 Wiley Periodicals, Inc.

In vivo single-shot (13)C spectroscopic imaging of hyperpolarized metabolites by spatiotemporal encoding

DEFF Research Database (Denmark)

Schmidt, Rita; Laustsen, Christoffer; Dumez, Jean-Nicolas

2014-01-01

are necessary. Several approaches have been customized for hyperpolarized (13)C MRI, including CSI with a center-out k-space encoding, EPSI, and spectrally selective pulses in combination with spiral EPI acquisitions. Recent studies have described the potential of single-shot alternatives based...... temporal) data sets were obtained at 7T from a murine lymphoma tumor model....

Value of selective MIP reconstructions of respiratory triggered 3D-TSE-MR cholangiography on a workstation versus standard MIP reconstructions and single-shot MRCP

International Nuclear Information System (INIS)

Schaible, R.; Textor, J.; Kreft, B.; Schild, H.; Neubrand, M.

2001-01-01

Comparison of anatomical visualisation and diagnostic value of selective MIP reconstructions of respiratory triggered 3D-TSE-MRCP versus standard MIP reconstructions and single-shot MRCP. Material and Methods: 50 patients with pancreaticobiliary disease were examined at 1.5 Tesla (ACS NT II, Philips Medical Systems) using a breath-hold single-shot (SS) and a respiratory triggered 3D-TSE-MRCP technique in 12 standard MIP projections. Additional selective MIP reconstructions with different slice thickness (2, 4, 10 cm) and projections were performed on a workstation. Visualization of the pancreaticobiliary system and the diagnostic value of the examinations were analysed. Results: Single-shot and 3D-TSE in standard projections showed comparable anatomical visualisation. On selective MIP reconstructions the biliary system (SS p [de

Clinical application of multi-shot diffusion EPI in neurological disease

International Nuclear Information System (INIS)

Ishihara, Tetsuya; Hirata, Koichi; Kubo, Jin; Yamazaki, Kaoru; Sato, Toshihiko

1998-01-01

Using the multi-shot EPI method we investigated the clinical application of diffusion weighted imaging (DWI) in the diagnosis of neurological disease. The multi-shot method provided better susceptibility artifact-free DWI than the single-shot method particularly in the region of the posterior cranial fossa. DWI using the multi-shot EPI method readily shows the pyramidal tract extending from the internal capsule to the brainstems which is inaccessible by the conventional single-shot EPI method, and providing three-dimensional and distinct images of pyramidal tract changes in amyotrophic lateral sclerosis or cerebral infarction with pyramidal tract disturbance. Our findings suggest that the use of DWI with the multi-shot EPI method would provide a technique for the easy diagnosis and evaluation of various neurological diseases. (author)

Clinical application of multi-shot diffusion EPI in neurological disease

Energy Technology Data Exchange (ETDEWEB)

Ishihara, Tetsuya; Hirata, Koichi; Kubo, Jin; Yamazaki, Kaoru [Dokkyo Univ., Mibu, Tochigi (Japan). School of Medicine; Sato, Toshihiko

1998-05-01

Using the multi-shot EPI method we investigated the clinical application of diffusion weighted imaging (DWI) in the diagnosis of neurological disease. The multi-shot method provided better susceptibility artifact-free DWI than the single-shot method particularly in the region of the posterior cranial fossa. DWI using the multi-shot EPI method readily shows the pyramidal tract extending from the internal capsule to the brainstems which is inaccessible by the conventional single-shot EPI method, and providing three-dimensional and distinct images of pyramidal tract changes in amyotrophic lateral sclerosis or cerebral infarction with pyramidal tract disturbance. Our findings suggest that the use of DWI with the multi-shot EPI method would provide a technique for the easy diagnosis and evaluation of various neurological diseases. (author)

Tabletop single-shot extreme ultraviolet Fourier transform holography of an extended object.

Science.gov (United States)

Malm, Erik B; Monserud, Nils C; Brown, Christopher G; Wachulak, Przemyslaw W; Xu, Huiwen; Balakrishnan, Ganesh; Chao, Weilun; Anderson, Erik; Marconi, Mario C

2013-04-22

We demonstrate single and multi-shot Fourier transform holography with the use of a tabletop extreme ultraviolet laser. The reference wave was produced by a Fresnel zone plate with a central opening that allowed the incident beam to illuminate the sample directly. The high reference wave intensity allows for larger objects to be imaged compared to mask-based lensless Fourier transform holography techniques. We obtain a spatial resolution of 169 nm from a single laser pulse and a resolution of 128 nm from an accumulation of 20 laser pulses for an object ~11x11μm(2) in size. This experiment utilized a tabletop extreme ultraviolet laser that produces a highly coherent ~1.2 ns laser pulse at 46.9 nm wavelength.

A TV camera system for digitizing single shot oscillograms at sweep rate of 0.1 ns/cm

International Nuclear Information System (INIS)

Kienlen, M.; Knispel, G.; Miehe, J.A.; Sipp, B.

1976-01-01

A TV camera digitizing system associated with a 5 GHz photocell-oscilloscope apparatus allows the digitizing of single shot oscillograms; with an oscilloscope sweep rate of 0.1 ns/cm an accuracy on time measurements of 4 ps is obtained [fr

Single-shot full strain tensor determination with microbeam X-ray Laue diffraction and a two-dimensional energy-dispersive detector.

Science.gov (United States)

Abboud, A; Kirchlechner, C; Keckes, J; Conka Nurdan, T; Send, S; Micha, J S; Ulrich, O; Hartmann, R; Strüder, L; Pietsch, U

2017-06-01

The full strain and stress tensor determination in a triaxially stressed single crystal using X-ray diffraction requires a series of lattice spacing measurements at different crystal orientations. This can be achieved using a tunable X-ray source. This article reports on a novel experimental procedure for single-shot full strain tensor determination using polychromatic synchrotron radiation with an energy range from 5 to 23 keV. Microbeam X-ray Laue diffraction patterns were collected from a copper micro-bending beam along the central axis (centroid of the cross section). Taking advantage of a two-dimensional energy-dispersive X-ray detector (pnCCD), the position and energy of the collected Laue spots were measured for multiple positions on the sample, allowing the measurement of variations in the local microstructure. At the same time, both the deviatoric and hydrostatic components of the elastic strain and stress tensors were calculated.

Optimization of laser energy deposition for single-shot high aspect-ratio microstructuring of thick BK7 glass

Energy Technology Data Exchange (ETDEWEB)

Garzillo, Valerio; Grigutis, Robertas [Dipartimento di Scienza e Alta Tecnologia, University of Insubria, Via Valleggio 11, I-22100 Como (Italy); Jukna, Vytautas [Centre de Physique Theorique, CNRS, Ecole Polytechnique, Université Paris-Saclay, F-91128 Palaiseau (France); LOA, ENSTA-ParisTech, CNRS, Ecole Polytechnique, Université Paris Saclay, F-91762 Palaiseau (France); Couairon, Arnaud [Centre de Physique Theorique, CNRS, Ecole Polytechnique, Université Paris-Saclay, F-91128 Palaiseau (France); Di Trapani, Paolo [Dipartimento di Scienza e Alta Tecnologia, University of Insubria and CNISM UdR Como, Via Valleggio 11, I-22100 Como (Italy); Jedrkiewicz, Ottavia, E-mail: ottavia.jedrkiewicz@ifn.cnr.it [Istituto di Fotonica e Nanotecnologie, CNR and CNISM UdR Como, Via Valleggio 11, I-22100 Como (Italy)

2016-07-07

We investigate the generation of high aspect ratio microstructures across 0.7 mm thick glass by means of single shot Bessel beam laser direct writing. We study the effect on the photoinscription of the cone angle, as well as of the energy and duration of the ultrashort laser pulse. The aim of the study is to optimize the parameters for the writing of a regular microstructure due to index modification along the whole sample thickness. By using a spectrally resolved single pulse transmission diagnostics at the output surface of the glass, we correlate the single shot material modification with observations of the absorption in different portions of the retrieved spectra, and with the absence or presence of spectral modulation. Numerical simulations of the evolution of the Bessel pulse intensity and of the energy deposition inside the sample help us interpret the experimental results that suggest to use picosecond pulses for an efficient and more regular energy deposition. Picosecond pulses take advantage of nonlinear plasma absorption and avoid temporal dynamics effects which can compromise the stationarity of the Bessel beam propagation.

The single-shot opto-digitizer

International Nuclear Information System (INIS)

Nail, M.; Gibert, Ph.

2000-01-01

Laser-plasma experiments need to measure signals provided either by X-ray, photonic or neutronic detector. The measurement should have 50 GHz bandwidth and up to several hundred of Giga-Hertz for sub picosecond plasmas. For this purpose, a 35 GHz single shot opto-digitizer (10 ps risetime) has been studied and built. The device is made up of a 50 ohms microstrip propagation line, periodically lined by 100 sampled gates. The propagation line is long enough to measure a 400 ps duration. The sampling rate is 250 Gsa/s (every 4 ps). The sampled gates are made with fast recombining photo-material and turn on by a subpicosecond laser pulse which is synchronized exactly with the analysed phenomena. Every gate is recording to a storing capacitor. After the recording, every capacitor charge is needed to built the signal that was displayed on the propagation line. The dynamic range of measurement is 47 for the entire device. The device can measure positive or negative signals from 1.5 to 70 Volts. To increase the bandwidth, two another kinds of opto-digitizer were studied: one is a buried stripline with 56 GHz band width, the other a 70 GHz coplanar transmission line. For the purpose of subpicosecond plasmas, a 30 coplanar waveguide opto-digitizer was studied. Characteristics are as followed: window of measurement 40 ps, sampling rate 1 ps, bandwidth 230 GHz. Finally, a bundle of optical fibers was used to propagate the laser beam on semiconductor gates. If the gates are lighted at the same time, i.e. if the optical fibers have the same length, we get a simultaneous addressing. By using different lengths of optical fibers, we can do a sequential addressing. So, the sampling rate becomes a combination of the distance between two adjacent sampled channels, and the difference in length of optical fibers. (author)

Shot reproducibility of the self-magnetic-pinch diode at 4.5 MV

OpenAIRE

Nichelle Bennett; M. Dale Crain; Darryl W. Droemer; Raymond E. Gignac; Greg Lare; Isidro Molina; Robert Obregon; Chase C. Smith; Frank L. Wilkins; Dale R. Welch; Steve Cordova; Manuel L. Gallegos; Mark D. Johnston; Mark L. Kiefer; Joshua J. Leckbee

2014-01-01

In experiments conducted at Sandia National Laboratories’ RITS-6 accelerator, the self-magnetic-pinch diode exhibits significant shot-to-shot variability. Specifically, for identical hardware operated at the same voltage, some shots exhibit a catastrophic drop in diode impedance. A study is underway to identify sources of shot-to-shot variations which correlate with diode impedance collapse. The scope of this report is limited to data collected at 4.5-MV peak voltage and sources of variabilit...

Single-Shot, Volumetrically Illuminated, Three-Dimensional, Tomographic Laser-Induced-Fluorescence Imaging in a Gaseous Free Jet

Science.gov (United States)

2016-04-28

Single-shot, volumetrically illuminated, three- dimensional, tomographic laser-induced- fluorescence imaging in a gaseous free jet Benjamin R. Halls...acquisition; (110.6955) Tomographic imaging ; (110.6960) Tomography; (280.2490) Flow diagnostics; (300.2530) Fluorescence , laser-induced...84 (1983). 2. I. van Cruyningen, A. Lozano, and R. K. Hanson, “Quantitative imaging of concentration by planar laser-induced fluorescence ,” Exp

Investigations of shot reproducibility for the SMP diode at 4.5 MV.

Energy Technology Data Exchange (ETDEWEB)

Bennett, Nichelle [National Security Technologies, LLC, Las Vegas, NV (United States); Crain, Marlon D. [National Security Technologies, LLC, Las Vegas, NV (United States); Droemer, Darryl W. [National Security Technologies, LLC, Las Vegas, NV (United States); Gignac, Raymond Edward [National Security Technologies, LLC, Las Vegas, NV (United States); Lare, Gregory A. [National Security Technologies, LLC, Las Vegas, NV (United States); Molina, Isidro [National Security Technologies, LLC, Las Vegas, NV (United States); Obregon, Rafael [National Security Technologies, LLC, Las Vegas, NV (United States); Smith, Chase C. [National Security Technologies, LLC, Las Vegas, NV (United States); Wilkins, Frank Lee [National Security Technologies, LLC, Las Vegas, NV (United States); Welch, Dale Robert [Voss Scientific, LLC, Albuquerque, NM (United States); Cordova, Steve Ray; Gallegos, M.; Johnston, Mark D.; Kiefer, Mark Linden; Leckbee, Joshua J.; Nielsen, Daniel Scott; Oliver, Bryan Velten; Renk, Timothy Jerome; Romero, Tobias; Webb, Timothy Jay; Ziska, Derek Raymond

2013-11-01

In experiments conducted on the RITS-6 accelerator, the SMP diode exhibits sig- ni cant shot-to-shot variability. Speci cally, for identical hardware operated at the same voltage, some shots exhibit a catastrophic drop in diode impedance. A study is underway to identify sources of shot-to-shot variations which correlate with diode impedance collapse. To remove knob emission as a source, only data from a shot series conducted with a 4.5-MV peak voltage are considered. The scope of this report is limited to sources of variability which occur away from the diode, such as power ow emission and trajectory changes, variations in pulsed power, dustbin and transmission line alignment, and di erent knob shapes. We nd no changes in the transmission line hardware, alignment, or hardware preparation methods which correlate with impedance collapse. However, in classifying good versus poor shots, we nd that there is not a continuous spectrum of diode impedance behavior but that the good and poor shots can be grouped into two distinct impedance pro les. This result forms the basis of a follow-on study focusing on the variability resulting from diode physics. 3

Single-shot quantitative phase microscopy with color-multiplexed differential phase contrast (cDPC.

Directory of Open Access Journals (Sweden)

Zachary F Phillips

Full Text Available We present a new technique for quantitative phase and amplitude microscopy from a single color image with coded illumination. Our system consists of a commercial brightfield microscope with one hardware modification-an inexpensive 3D printed condenser insert. The method, color-multiplexed Differential Phase Contrast (cDPC, is a single-shot variant of Differential Phase Contrast (DPC, which recovers the phase of a sample from images with asymmetric illumination. We employ partially coherent illumination to achieve resolution corresponding to 2× the objective NA. Quantitative phase can then be used to synthesize DIC and phase contrast images or extract shape and density. We demonstrate amplitude and phase recovery at camera-limited frame rates (50 fps for various in vitro cell samples and c. elegans in a micro-fluidic channel.

Single-shot secure quantum network coding on butterfly network with free public communication

Science.gov (United States)

Owari, Masaki; Kato, Go; Hayashi, Masahito

2018-01-01

Quantum network coding on the butterfly network has been studied as a typical example of quantum multiple cast network. We propose a secure quantum network code for the butterfly network with free public classical communication in the multiple unicast setting under restricted eavesdropper’s power. This protocol certainly transmits quantum states when there is no attack. We also show the secrecy with shared randomness as additional resource when the eavesdropper wiretaps one of the channels in the butterfly network and also derives the information sending through public classical communication. Our protocol does not require verification process, which ensures single-shot security.

Moderately T2-weighted images obtained with the single-shot fast spin-echo technique. Differentiating between malignant and benign urinary obstructions

International Nuclear Information System (INIS)

Obuchi, Masao; Sugimoto, Hideharu; Kubota, Hayato; Yamamoto, Wakako; Kinebuchi, Yuko; Honda, Minoru; Takahara, Taro

2002-01-01

The purpose of this study was to determine whether a distinction could be made between benign and malignant urinary obstructions in moderately T 2 -weighted images obtained with the single-shot fast spin-echo technique. Forty-four lesions in 39 patients with urinary obstruction were evaluated with the single-shot fast spin-echo (SSFSE) technique with an effective TE of 90-100 ms and without fat saturation. Benign and malignant lesions were compared for the presence of ureteral wall thickening and a signal intensity relative to the proximal ureteral wall. Statistically significant differences were found between benign and malignant lesions in both morphologic change (P 2 -weighted SSFSE technique without fat saturation can accurately distinguish between benign and malignant urinary obstructions. (author)

Single shot imaging through turbid medium and around corner using coherent light

Science.gov (United States)

Li, Guowei; Li, Dayan; Situ, Guohai

2018-01-01

Optical imaging through turbid media and around corner is a difficult challenge. Even a very thin layer of a turbid media, which randomly scatters the probe light, can appear opaque and hide any objects behind it. Despite many recent advances, no current method can image the object behind turbid media with single record using coherent laser illumination. Here we report a method that allows non-invasive single-shot optical imaging through turbid media and around corner via speckle correlation. Instead of being as an obstacle in forming diffractionlimited images, speckle actually can be a carrier that encodes sufficient information to imaging through visually opaque layers. Optical imaging through turbid media and around corner is experimentally demonstrated using traditional imaging system with the aid of iterative phase retrieval algorithm. Our method require neither scan of illumination nor two-arm interferometry or long-time exposure in acquisition, which has new implications in optical sensing through common obscurants such as fog, smoke and haze.

Single-shot parallel full range complex Fourier-domain optical coherence tomography

International Nuclear Information System (INIS)

Huang Bingjie; Bu Peng; Nan Nan; Wang Xiangzhao

2011-01-01

We present a method of parallel full range complex Fourier-domain optical coherence tomography (FDOCT) that is capable of acquiring an artifacts-free two-dimensional (2-D) cross-sectional image, i.e. a full range B-scan tomogram, by a single shot of 2-D CCD camera. This method is based on a spatial carrier technique, in which the spatial carrier-frequency is instantaneously introduced into the 2-D spectral interferogram registered in parallel FDOCT by using a grating-generated reference beam. The spatial-carrier-contained 2-D spectral interferogram is processed through Fourier transformation to obtain a complex 2-D spectral interferogram. From the 2-D complex spectral interferomgram, a full range B-scan tomogram is reconstructed. The principle of our method is confirmed by imaging an onion sample.

A versatile diffractive maskless lithography for single-shot and serial microfabrication.

Science.gov (United States)

Jenness, Nathan J; Hill, Ryan T; Hucknall, Angus; Chilkoti, Ashutosh; Clark, Robert L

2010-05-24

We demonstrate a diffractive maskless lithographic system that is capable of rapidly performing both serial and single-shot micropatterning. Utilizing the diffractive properties of phase holograms displayed on a spatial light modulator, arbitrary intensity distributions were produced to form two and three dimensional micropatterns/structures in a variety of substrates. A straightforward graphical user interface was implemented to allow users to load templates and change patterning modes within the span of a few minutes. A minimum resolution of approximately 700 nm is demonstrated for both patterning modes, which compares favorably to the 232 nm resolution limit predicted by the Rayleigh criterion. The presented method is rapid and adaptable, allowing for the parallel fabrication of microstructures in photoresist as well as the fabrication of protein microstructures that retain functional activity.

Simultaneous single-shot readout of multi-qubit circuits using a traveling-wave parametric amplifier

Science.gov (United States)

O'Brien, Kevin

Observing and controlling the state of ever larger quantum systems is critical for advancing quantum computation. Utilizing a Josephson traveling wave parametric amplifier (JTWPA), we demonstrate simultaneous multiplexed single shot readout of 10 transmon qubits in a planar architecture. We employ digital image sideband rejection to eliminate noise at the image frequencies. We quantify crosstalk and infidelity due to simultaneous readout and control of multiple qubits. Based on current amplifier technology, this approach can scale to simultaneous readout of at least 20 qubits. This work was supported by the Army Research Office.

Ultrafast Single-Shot Optical Oscilloscope based on Time-to-Space Conversion due to Temporal and Spatial Walk-Off Effects in Nonlinear Mixing Crystal

Science.gov (United States)

Takagi, Yoshihiro; Yamada, Yoshifumi; Ishikawa, Kiyoshi; Shimizu, Seiji; Sakabe, Shuji

2005-09-01

A simple method for single-shot sub-picosecond optical pulse diagnostics has been demonstrated by imaging the time evolution of the optical mixing onto the beam cross section of the sum-frequency wave when the interrogating pulse passes over the tested pulse in the mixing crystal as a result of the combined effect of group-velocity difference and walk-off beam propagation. A high linearity of the time-to-space projection is deduced from the process solely dependent upon the spatial uniformity of the refractive indices. A snap profile of the accidental coincidence between asynchronous pulses from separate mode-locked lasers has been detected, which demonstrates the single-shot ability.

SunShot Initiative Fact Sheet

Energy Technology Data Exchange (ETDEWEB)

DOE Solar Energy Technologies Office

2015-04-01

The U.S. Department of Energy (DOE) SunShot Initiative is a collaborative national effort launched in 2011 that aggressively drives innovation to make solar energy fully cost competitive with traditional energy sources before the end of the decade. The SunShot fact sheet outlines goals and successes of the program as it works with private companies, universities, non-profit organizations, state and local governments, and national laboratories to drive down the cost of solar electricity to $0.06 per kilowatt-hour, without incentives, by the year 2020.

Single-shot Thomson scattering on argon plasmas created by the Microwave Plasma Torch; evidence for a new plasma class

NARCIS (Netherlands)

Mullen, van der J.J.A.M.; Sande, van de M.J.; Vries, de N.; Broks, B.H.P.; Iordanova, E.I.; Gamero, A.; Torres, J.; Sola, A.

2007-01-01

To determine the fine-structure size of plasmas created by a Microwave Plasma Torch (MPT), single-shot Thomson scattering (TS) measurements were performed. The aim was to find a solution for the long-standing discrepancy between experiments and Global Plasma Models (GPMs). Since these GPMs are based

Ship Detection Using Transfer Learned Single Shot Multi Box Detector

Directory of Open Access Journals (Sweden)

Nie Gu-Hong

2017-01-01

Full Text Available Ship detection in satellite images is a challenging task. In this paper, we introduce a transfer learned Single Shot MultiBox Detector (SSD for ship detection. To this end, a state-of-the-art object detection model pre-trained from a large number of natural images was transfer learned for ship detection with limited labeled satellite images. To the best of our knowledge, this could be one of the first studies which introduce SSD into ship detection on satellite images. Experiments demonstrated that our method could achieve 87.9% AP at 47 FPS using NVIDIA TITAN X. In comparison with Faster R-CNN, 6.7% AP improvement could be achieved. Effects of the observation resolution has also been studied with the changing input sizes among 300 × 300, 600 × 600 and 900 × 900. It has been noted that the detection accuracy declined sharply with the decreasing resolution that is mainly caused by the missing small ships.

3 ns single-shot read-out in a quantum dot-based memory structure

International Nuclear Information System (INIS)

Nowozin, T.; Bimberg, D.; Beckel, A.; Lorke, A.; Geller, M.

2014-01-01

Fast read-out of two to six charges per dot from the ground and first excited state in a quantum dot (QD)-based memory is demonstrated using a two-dimensional electron gas. Single-shot measurements on modulation-doped field-effect transistor structures with embedded InAs/GaAs QDs show read-out times as short as 3 ns. At low temperature (T = 4.2 K) this read-out time is still limited by the parasitics of the setup and the device structure. Faster read-out times and a larger read-out signal are expected for an improved setup and device structure

Lichtheim’s Golden shot

NARCIS (Netherlands)

Eling, P.A.T.M.

2011-01-01

Lichtheim belongs to the ranks of most famous aphasiologists, in particular because of a diagram often referred to as ‘Lichtheim’s House’. His single paper on aphasia has drawn the attention of the aphasiological community for many years and may be considered a golden shot. But it became, to

Accelerator-based Single-shot Ultrafast Transmission Electron Microscope with Picosecond Temporal Resolution and Nanometer Spatial Resolution

OpenAIRE

Xiang, D.; Fu, F.; Zhang, J.; Huang, X.; Wang, L.; Wang, X.; Wan, W.

2014-01-01

We present feasibility study of an accelerator-based ultrafast transmission electron microscope (u-TEM) capable of producing a full field image in a single-shot with simultaneous picosecond temporal resolution and nanometer spatial resolution. We study key physics related to performance of u-TEMs, and discuss major challenges as well as possible solutions for practical realization of u-TEMs. The feasibility of u-TEMs is confirmed through simulations using realistic electron beam parameters. W...

Bond strength investigation of two shot moulded polymer

DEFF Research Database (Denmark)

Islam, Mohammad Aminul

This report on the project “Bond strength investigation of two shot moulded polymers” has been submitted for fulfilling the requirements for the course “Experimental Plastic Technology – 42234” at IPL-DTU. Two shot moulding is a classic manufacturing process to combine two different polymers...... in a single product and it is getting more and more importance day by day. One of the biggest challenges of two shot moulding is to achieve a reasonably good bonding between two polymers. The purpose of this project is to investigate the effects of different process, material and machine parameters...... on the bond strength of two shot moulded polymers. For the experiments two engineering polymers (PS and ABS) were used. After all the experimental work, several parameters were found which could effectively control the bond strength of two shot moulded polymers. This report also presents different aspects...

Spectrometer for shot-to-shot photon energy characterization in the multi-bunch mode of the free electron laser at Hamburg

International Nuclear Information System (INIS)

Palutke, S.; Wurth, W.; Gerken, N. C.; Mertens, K.; Klumpp, S.; Martins, M.; Mozzanica, A.; Schmitt, B.; Wunderer, C.; Graafsma, H.; Meiwes-Broer, K.-H.

2015-01-01

The setup and first results from commissioning of a fast online photon energy spectrometer for the vacuum ultraviolet free electron laser at Hamburg (FLASH) at DESY are presented. With the use of the latest advances in detector development, the presented spectrometer reaches readout frequencies up to 1 MHz. In this paper, we demonstrate the ability to record online photon energy spectra on a shot-to-shot base in the multi-bunch mode of FLASH. Clearly resolved shifts in the mean wavelength over the pulse train as well as shot-to-shot wavelength fluctuations arising from the statistical nature of the photon generating self-amplified spontaneous emission process have been observed. In addition to an online tool for beam calibration and photon diagnostics, the spectrometer enables the determination and selection of spectral data taken with a transparent experiment up front over the photon energy of every shot. This leads to higher spectral resolutions without the loss of efficiency or photon flux by using single-bunch mode or monochromators

Femtosecond Single-Shot Imaging of Nanoscale Ferromagnetic Order in Co/Pd Multilayers using Resonant X-ray Holography

Energy Technology Data Exchange (ETDEWEB)

Wang, Tianhan; Zhu, Diling; Benny Wu,; Graves, Catherine; Schaffert, Stefan; Rander, Torbjorn; Muller, leonard; Vodungbo, Boris; Baumier, Cedric; Bernstein, David P.; Brauer, Bjorn; Cros, Vincent; Jong, Sanne de; Delaunay, Renaud; Fognini, Andreas; Kukreja, Roopali; Lee, Sooheyong; Lopez-Flores, Victor; Mohanty, Jyoti; Pfau, Bastian; Popescu, 5 Horia

2012-05-15

We present the first single-shot images of ferromagnetic, nanoscale spin order taken with femtosecond x-ray pulses. X-ray-induced electron and spin dynamics can be outrun with pulses shorter than 80 fs in the investigated fluence regime, and no permanent aftereffects in the samples are observed below a fluence of 25 mJ/cm{sup 2}. Employing resonant spatially-muliplexed x-ray holography results in a low imaging threshold of 5 mJ/cm{sup 2}. Our results open new ways to combine ultrafast laser spectroscopy with sequential snapshot imaging on a single sample, generating a movie of excited state dynamics.

Single-shot dual-wavelength in-line and off-axis hybrid digital holography

Science.gov (United States)

Wang, Fengpeng; Wang, Dayong; Rong, Lu; Wang, Yunxin; Zhao, Jie

2018-02-01

We propose an in-line and off-axis hybrid holographic real-time imaging technique. The in-line and off-axis digital holograms are generated simultaneously by two lasers with different wavelengths, and they are recorded using a color camera with a single shot. The reconstruction is carried using an iterative algorithm in which the initial input is designed to include the intensity of the in-line hologram and the approximate phase distributions obtained from the off-axis hologram. In this way, the complex field in the object plane and the output by the iterative procedure can produce higher quality amplitude and phase images compared to traditional iterative phase retrieval. The performance of the technique has been demonstrated by acquiring the amplitude and phase images of a green lacewing's wing and a living moon jellyfish.

Calculation of T2 relaxation time from ultrafast single shot sequences for differentiation of liver tumors. Comparison of echo-planar, HASTE, and spin-echo sequences

International Nuclear Information System (INIS)

Abe, Yasuko; Yamashita, Yasuyuki; Tang, Yi; Namimoto, Tomohiro; Takahashi, Mutsumasa

2000-01-01

The purpose of this study was to evaluate the accuracy of T2 calculation from single shot imaging sequences such as echo-planar imaging (EPI) and half-Fourier single shot turbo spin-echo (HASTE) imaging. For the phantom study, we prepared vials containing different concentrations of agarose, copper sulfate, and nickel chloride. The temperature of the phantom was kept at 22 deg C. MR images were obtained with a 1.5-Tesla superconductive magnet. Spin-echo (SE)-type EPI and HASTE sequences with different TEs were obtained for T2 calculation, and the T2 values were compared with those obtained from the Carr-Purcell-Meiborm-Gill (CPMG) sequence. The clinical study group consisted of 30 consecutive patients referred for MR imaging to characterize focal liver lesions. A total of 40 focal liver lesions were evaluated, including 25 primary or metastatic solid masses and 15 non-solid lesions. Single shot SE-type EPI and HASTE were both performed with TEs of 64 and 90 msec. In the phantom study, the T2 values obtained from both single shot sequences showed significant correlations with those from the CPMG sequence (T2 on EPI vs. T2 on CPMG: r=0.98, p<0.01; T2 on HASTE vs. T2 on CPMG: r=0.99, p<0.01). In the clinical study, mean T2 values for liver calculated from EPI (42 msec) were significantly shorter than those calculated from the HASTE sequence (58 msec) (p<0.001). Mean T2 values for solid tumors were 95 msec with HASTE and 72 msec with EPI, and mean T2 values for non-solid lesions were 128 msec with HASTE and 159 msec with EPI. Although mean T2 values between solid and non-solid lesions were significantly different for both EPI and HASTE sequences (p=0.01 for HASTE, p<0.001 for EPI), the overlap of solid and non-solid lesions was less frequent in EPI than in HASTE. With single shot sequences, it is possible to obtain the T2 values that show excellent correlation with the CPMG sequence. Although both HASTE and EPI are useful to calculate T2 values, EPI appears to be more

Land Streamer Surveying Using Multiple Sources

KAUST Repository

Mahmoud, Sherif

2014-12-11

Various examples are provided for land streamer seismic surveying using multiple sources. In one example, among others, a method includes disposing a land streamer in-line with first and second shot sources. The first shot source is at a first source location adjacent to a proximal end of the land streamer and the second shot source is at a second source location separated by a fixed length corresponding to a length of the land streamer. Shot gathers can be obtained when the shot sources are fired. In another example, a system includes a land streamer including a plurality of receivers, a first shot source located adjacent to the proximal end of the land streamer, and a second shot source located in-line with the land streamer and the first shot source. The second shot source is separated from the first shot source by a fixed overall length corresponding to the land streamer.

Urinary retention in unilateral total knee arthroplasty: comparison between continuous epidural analgesia and single-shot femoral nerve block

International Nuclear Information System (INIS)

Khan, A.A.; Khan, R.I.

2018-01-01

To compare the frequency of urinary retention and requirement of bladder catheterization in patients undergoing toatal knee arthroplasty while receiving either continuous epidural analgesia or single-shot femoral nerve block. Study Design: Randomized controlled study. Place and Duration of Study:Operating Rooms of Aga Khan University Hospital, Karachi, from January 2014 to January 2015. Methodology:Patients were randomized in two groups of 30 each, i.e. epidural group (group E) or femoral nerve block group (group F). Baseline parameters were recorded. Postoperatively, patients were followed for upto 24 hours to collect the data regarding urinary retention. Final outcome was taken at 24 hours postoperatively. Data was analyzed to compare the frequency of urinary retention between the two groups. Results:The average age of the patients was 59.58 +-5.85 years. There were 28 (46.7%) male and 32 (53.3%) female patients. Frequency of urinary retention was significantly high in Group E than Group F (46.7% vs. 6.7%; p=0.0005). Conclusion: Single-shot femoral nerve block offers a more favorable profile in terms of postoperative urinary retention when compared to continuous epidural analgesia. (author)

Single-shot mega-electronvolt ultrafast electron diffraction for structure dynamic studies of warm dense matter

Energy Technology Data Exchange (ETDEWEB)

Mo, M. Z., E-mail: mmo09@slac.stanford.edu; Shen, X.; Chen, Z.; Li, R. K.; Dunning, M.; Zheng, Q.; Weathersby, S. P.; Reid, A. H.; Coffee, R.; Makasyuk, I.; Edstrom, S.; McCormick, D.; Jobe, K.; Hast, C.; Glenzer, S. H.; Wang, X. [SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025 (United States); Sokolowski-Tinten, K. [Faculty of Physics and Centre for Nanointegration Duisburg-Essen, University of Duisburg-Essen, Lotharstrasse 1, D-47048 Duisburg (Germany)

2016-11-15

We have developed a single-shot mega-electronvolt ultrafast-electron-diffraction system to measure the structural dynamics of warm dense matter. The electron probe in this system is featured by a kinetic energy of 3.2 MeV and a total charge of 20 fC, with the FWHM pulse duration and spot size at sample of 350 fs and 120 μm respectively. We demonstrate its unique capability by visualizing the atomic structural changes of warm dense gold formed from a laser-excited 35-nm freestanding single-crystal gold foil. The temporal evolution of the Bragg peak intensity and of the liquid signal during solid-liquid phase transition are quantitatively determined. This experimental capability opens up an exciting opportunity to unravel the atomic dynamics of structural phase transitions in warm dense matter regime.

Real-Time, Single-Shot Temporal Measurements of Short Electron Bunches, Terahertz CSR and FEL Radiation

CERN Document Server

Berden, G; Van der Meer, A F G

2005-01-01

Electro-optic detection of the Coulomb field of electron bunches is a promising technique for single-shot measurements of the bunch length and shape in the sub-picosecond time domain. This technique has been applied to the measurement of 50 MeV electron bunches in the FELIX free electron laser, showing the longitudinal profile of single bunches of around 650 fs FWHM [Phys. Rev. Lett. 93, 114802 (2004)]. The method is non-destructive and real-time, and therefore ideal for online monitoring of the longitudinal shape of single electron bunches. At FELIX we have used it for real-time optimization of sub-picosecond electron bunches. Electro-optic detection has also been used to measure the electric field profiles of far-infrared (or terahertz) optical pulses generated by the relativistic electrons. We have characterised the far-infrared output of the free electron laser, and more recently, we have measured the temporal profile of terahertz optical pulses generated at one of the bending magnets.

High-speed single-shot optical focusing through dynamic scattering media with full-phase wavefront shaping

Science.gov (United States)

Hemphill, Ashton S.; Shen, Yuecheng; Liu, Yan; Wang, Lihong V.

2017-11-01

In biological applications, optical focusing is limited by the diffusion of light, which prevents focusing at depths greater than ˜1 mm in soft tissue. Wavefront shaping extends the depth by compensating for phase distortions induced by scattering and thus allows for focusing light through biological tissue beyond the optical diffusion limit by using constructive interference. However, due to physiological motion, light scattering in tissue is deterministic only within a brief speckle correlation time. In in vivo tissue, this speckle correlation time is on the order of milliseconds, and so the wavefront must be optimized within this brief period. The speed of digital wavefront shaping has typically been limited by the relatively long time required to measure and display the optimal phase pattern. This limitation stems from the low speeds of cameras, data transfer and processing, and spatial light modulators. While binary-phase modulation requiring only two images for the phase measurement has recently been reported, most techniques require at least three frames for the full-phase measurement. Here, we present a full-phase digital optical phase conjugation method based on off-axis holography for single-shot optical focusing through scattering media. By using off-axis holography in conjunction with graphics processing unit based processing, we take advantage of the single-shot full-phase measurement while using parallel computation to quickly reconstruct the phase map. With this system, we can focus light through scattering media with a system latency of approximately 9 ms, on the order of the in vivo speckle correlation time.

Shot-noise-limited monitoring and phase locking of the motion of a single trapped ion.

Science.gov (United States)

Bushev, P; Hétet, G; Slodička, L; Rotter, D; Wilson, M A; Schmidt-Kaler, F; Eschner, J; Blatt, R

2013-03-29

We perform a high-resolution real-time readout of the motion of a single trapped and laser-cooled Ba+ ion. By using an interferometric setup, we demonstrate a shot-noise-limited measurement of thermal oscillations with a resolution of 4 times the standard quantum limit. We apply the real-time monitoring for phase control of the ion motion through a feedback loop, suppressing the photon recoil-induced phase diffusion. Because of the spectral narrowing in the phase-locked mode, the coherent ion oscillation is measured with a resolution of about 0.3 times the standard quantum limit.

Shot reproducibility of the self-magnetic-pinch diode at 4.5 MV

Directory of Open Access Journals (Sweden)

Nichelle Bennett

2014-05-01

Full Text Available In experiments conducted at Sandia National Laboratories’ RITS-6 accelerator, the self-magnetic-pinch diode exhibits significant shot-to-shot variability. Specifically, for identical hardware operated at the same voltage, some shots exhibit a catastrophic drop in diode impedance. A study is underway to identify sources of shot-to-shot variations which correlate with diode impedance collapse. The scope of this report is limited to data collected at 4.5-MV peak voltage and sources of variability which occur away from the diode, such as sheath electron emission and trajectories, variations in pulsed power, load and transmission line alignment, and different field shapers. We find no changes in the transmission line hardware, alignment, or hardware preparation methods which correlate with impedance collapse. However, in classifying good versus poor shots, we find that there is not a continuous spectrum of diode impedance behavior but that the good and poor shots can be grouped into two distinct impedance profiles. In poor shots, the sheath current in the load region falls from 16%–30% of the total current to less than 10%. This result will form the basis of a follow-up study focusing on the variability resulting from diode physics.

Single-shot antithymocyte globulin (ATG) induction for pancreas/kidney transplantation: ATG-Fresenius versus Thymoglobulin.

Science.gov (United States)

Schulz, T; Papapostolou, G; Schenker, P; Kapischke, M

2005-03-01

Single-shot antithymocyte globulin (ATG) prior to reperfusion followed by tacrolimus (TAC), mycophenolate mofetil (MMF), and prednisolone (PRD) is an established induction therapy in simultaneous pancreas kidney transplant (SPK) recipients. We retrospectively analyzed 6-month data from 105 patients who received their first SPK. From January 1996 to December 2000, ATG-Fresenius was used. Since January 2001, Thymoglobulin has been administered. In the first group, 58 patients were treated with ATG-Fresenius (4-6 mg/kg body weight). In the second group, 47 patients received Thymoglobulin (1.5-2.5 mg/kg body weight). HLA-mismatch was comparable. After an observation period of 6 months, patients, kidney, and pancreas graft survival is 98.3%, 96.6%, and 93.1% in group I and 97.9%, 97.9%, and 85.1% in group II, respectively. In each group, one death with functioning graft (DWFG) was observed. Twenty (34.5%) acute rejection episodes (AR) were observed (18 patients) in group I. They were treated with steroids (n = 16) or steroids/OKT3 (n = 4). One kidney graft failure was observed due to rejection and one due to DWFG. Four pancreas grafts were lost (thrombosis, n = 2; AR, n = 1; DWFG, n = 1). In group II, 15 AR (31.9%) were seen in 12 patients and were treated with steroids (n = 12), steroids/ATG (n = 1), or steroids/OKT3 (n = 2). Seven pancreas (thrombosis, n = 5; rejection, n = 1; DWFG, n = 1) and one kidney (DWFG, n = 1) graft losses occurred. These data clearly establish that single-shot ATG prior to reperfusion, followed by TAC, MMF, and PRD results in a low incidence of AR (34.5% in group I and 31.9% in group II) after SPK. Only 6.9% (group I) and 6.4% (group II) of the patients received antibodies for rejection treatment.

Centrically reordered inversion recovery half-Fourier single-shot turbo spin-echo sequence: improvement of the image quality of oxygen-enhanced MRI

International Nuclear Information System (INIS)

Ohno, Yoshiharu; Hatabu, Hiroto; Higashino, Takanori; Kawamitsu, Hideaki; Watanabe, Hirokazu; Takenaka, Daisuke; Cauteren, Marc van; Sugimura, Kazuro

2004-01-01

Purpose: The purpose of the study presented here was to determine the improvement in image quality of oxygen-enhanced magnetic resonance (MR) subtraction imaging obtained with a centrically reordered inversion recovery half-Fourier single-shot turbo spin-echo (c-IR-HASTE) sequence compared with that obtained with a conventional sequentially reordered inversion recovery single-shot HASTE (s-IR-HASTE) sequence for pulmonary imaging. Materials and methods: Oxygen-enhanced MR imaging using a 1.5 T whole body scanner was performed on 12 healthy, non-smoking volunteers. Oxygen-enhanced MR images were obtained with the coronal two-dimensional (2D) c-IR-HASTE sequence and 2D s-IR-HASTE sequence combined with respiratory triggering. For a 256x256 matrix, 132 phase-encoding steps were acquired including four steps for phase correction. Inter-echo spacing for each sequence was 4.0 ms. The effective echo time (TE) for c-IR-HASTE was 4.0 ms, and 16 ms for s-IR-HASTE. The inversion time (TI) was 900 ms. To determine the improvement in oxygen-enhanced MR subtraction imaging by c-IR-HASTE, CNRs of subtraction image, overall image quality, and image degradation of the c-IR-HASTE and s-IR-HASTE techniques were statistically compared. Results: CNR, overall image quality, and image degradation of c-IR-HASTE images showed significant improvement compared to those s-IR-HASTE images (P<0.05). Conclusion: Centrically reordered inversion recovery half-Fourier single-shot turbo spin-echo (c-IR-HASTE) sequence enhanced the signal from the lung and improved the image quality of oxygen-enhanced MR subtraction imaging

A Shack-Hartmann Sensor for Single-Shot Multi-Contrast Imaging with Hard X-rays

Directory of Open Access Journals (Sweden)

Tomy dos Santos Rolo

2018-05-01

Full Text Available An array of compound refractive X-ray lenses (CRL with 20 × 20 lenslets, a focal distance of 20cm and a visibility of 0.93 is presented. It can be used as a Shack-Hartmann sensor for hard X-rays (SHARX for wavefront sensing and permits for true single-shot multi-contrast imaging the dynamics of materials with a spatial resolution in the micrometer range, sensitivity on nanosized structures and temporal resolution on the microsecond scale. The object’s absorption and its induced wavefront shift can be assessed simultaneously together with information from diffraction channels. In contrast to the established Hartmann sensors the SHARX has an increased flux efficiency through focusing of the beam rather than blocking parts of it. We investigated the spatiotemporal behavior of a cavitation bubble induced by laser pulses. Furthermore, we validated the SHARX by measuring refraction angles of a single diamond CRL, where we obtained an angular resolution better than 4 μ rad.

Comparison of ropivacaine and bupivacaine as single-shot epidural anaesthesia for orthopaedic surgery

International Nuclear Information System (INIS)

Riaz, A.; Khan, A.S.

2015-01-01

To compare the efficacy and side-effects of 0.5% ropivacaine with that of 0.5% bupivacaine when used for single-shot epidural anaesthesia for orthopaedic surgery. Design: Randomized controlled trial. Place and Duration of Study: Department of Anesthesiology, Combined Military Hospital Rawalpindi, over a period of eight months from June 2013 to January 2014. Patients and Methods: The study was carried out in 60 ASA physical status I, II or III patients undergoing elective lower extremity orthopedic surgery. Two groups of 30 patients each received single-shot epidural anaesthesia either with ropivacaine 0.5% (ropivacaine group) or bupivacaine 0.5% (bupivacaine group). Onset, time for maximum height and median height of sensory block was assessed as well as time to two segment recession. Modified Bromage scale was used for motor blockade. Total duration of motor block and common side effects were also recorded. Results: The patients in both groups were similar in age, height, weight, gender and ASA status. There was no significant difference in onset of sensory block and time for maximum height of sensory block. The median heighest level of sensory block was T6 (T5-T8) for ropivacaine group and T5 (T4-T7) for bupivacaine group. Time for two segment regression and duration of sensory block were also comparable for both groups. The total duration of motor block was significantly more in bupivacaine group (159 min vs 134.2 min, p< 0.001). Modified Bromage scale was also significantly higher in bupivacaine group (2.86 vs 1.96 min, p<0.001). Side effects like hypotension, bradycardia, nausea, vomiting and shivering were similar in both groups. Conclusion: Epidural administration of 0.5% ropivacaine provided effective and good quality anaesthesia. Motor blockade was of less duration as compared to equivalent dose of 0.5% bupivacaine, which may offer potential benefit of early patient mobilization after orthopaedic surgery. (author)

Experimental results from CEM-UTS single shot 9 mj railgun

International Nuclear Information System (INIS)

Hayes, R.J.; Zowarka, R.C.

1991-01-01

The Center for Electromechanics at the University of Texas at Austin (CEM-UT) has designed and fabricated a 10-m long 90 mm bore railgun. During the test program, a number of solid armatures and projectile packages have been tested in a 50 m deep vertical test range. The experiments are powered by six homopolar generator (HPG) charged inductive stores, sequentially staged to provide the desired acceleration profile. Prior to testing, computer simulations are run to determine the preferred current profile and predict system performance. During projectile flight, high speed films, x-rays, muzzle volts, and velocity/acceleration profiles are recorded along with power supply operating parameters. Postshot diagnostics include bore wear analysis and armature and target recovery. Comparisons of predicted and recorded shot performance are also made. On selected tests, an energy balance is performed to determine efficiencies of the various system components. In this paper, a summary of all 90 mm gun shots is presented along with critical data collected from selected tests

Pre-shot simulations of far-field ground motion for the Source Physics Experiment (SPE) Explosions at the Climax Stock, Nevada National Security Site: SPE2

Energy Technology Data Exchange (ETDEWEB)

Mellors, R J; Rodgers, A; Walter, W; Ford, S; Xu, H; Matzel, E; Myers, S; Petersson, N A; Sjogreen, B; Hauk, T; Wagoner, J

2011-10-18

The Source Physics Experiment (SPE) is planning a 1000 kg (TNT equivalent) shot (SPE2) at the Nevada National Security Site (NNSS) in a granite borehole at a depth (canister centroid) of 45 meters. This shot follows an earlier shot of 100 kg in the same borehole at a depth 60 m. Surrounding the shotpoint is an extensive array of seismic sensors arrayed in 5 radial lines extending out 2 km to the north and east and approximately 10-15 to the south and west. Prior to SPE1, simulations using a finite difference code and a 3D numerical model based on the geologic setting were conducted, which predicted higher amplitudes to the south and east in the alluvium of Yucca Flat along with significant energy on the transverse components caused by scattering within the 3D volume along with some contribution by topographic scattering. Observations from the SPE1 shot largely confirmed these predictions although the ratio of transverse energy relative to the vertical and radial components was in general larger than predicted. A new set of simulations has been conducted for the upcoming SPE2 shot. These include improvements to the velocity model based on SPE1 observations as well as new capabilities added to the simulation code. The most significant is the addition of a new source model within the finite difference code by using the predicted ground velocities from a hydrodynamic code (GEODYN) as driving condition on the boundaries of a cube embedded within WPP which provides a more sophisticated source modeling capability linked directly to source site materials (e.g. granite) and type and size of source. Two sets of SPE2 simulations are conducted, one with a GEODYN source and 3D complex media (no topography node spacing of 5 m) and one with a standard isotropic pre-defined time function (3D complex media with topography, node spacing of 5 m). Results were provided as time series at specific points corresponding to sensor locations for both translational (x,y,z) and rotational

Zero-Shot Style Transfer in Text Using Recurrent Neural Networks

OpenAIRE

Carlson, Keith; Riddell, Allen; Rockmore, Daniel

2017-01-01

Zero-shot translation is the task of translating between a language pair where no aligned data for the pair is provided during training. In this work we employ a model that creates paraphrases which are written in the style of another existing text. Since we provide the model with no paired examples from the source style to the target style during training, we call this task zero-shot style transfer. Herein, we identify a high-quality source of aligned, stylistically distinct text in Bible ve...

Diffusion-weighted single shot echo planar imaging of colorectal cancer using a sensitivity-encoding technique

International Nuclear Information System (INIS)

Nasu, Katsuhiro; Kuroki, Yoshihumi; Murakami, Koji; Nawano, Shigeru; Kuroki, Seiko; Moriyama, Noriyuki

2004-01-01

We wanted to determine the feasibility of diffusion-weighted single shot echo planar imaging using a sensitivity encoding diffusion weighted imaging (SENSE-DWI) technique in depicting colorectal cancer. Forty-two patients with sigmoid colon cancer and rectal cancer, all proven pathologically, were examined on T2-turbo spin echo (TSE) and SENSE-DWI. No bowel preparation was performed before examination. The b-factors used in SENSE-DWI were zero and 1000 s/mm 2 . In 10 randomly selected cases, the images whose b-factors were 250 and 500 s/mm 2 were also obtained. The reduction factor of SENSE was 2.0 in all sequences. Two radiologists evaluated the obtained images from the viewpoints of tumor detectability, image distortion and misregistration of the tumors. The apparent diffusion coefficients (ADCs) of the tumors and urine in the urinary bladders in each patient were measured to evaluate the correlation between ADC and pathological classification of each tumor. All tumors were depicted hyperintensely on SENSE-DWI. Even though single shot echo planar imaging (EPI) was used, the image distortion and misregistration was quite pronounced because of simultaneous use of SENSE. On SENSE-DWI whose b-factor was 1000 s/mm 2 , the normal colon wall and feces were always hypointense and easily differentiated from the tumors. The mean ADC value of each tumor was 1.02±0.1 (x 10 -3 ) mm 2 /s. No overt correlation can be pointed out between ADC and pathological classification of each tumor. SENSE-DWI is a feasible method for depicting colorectal cancer. SENSE-DWI provides strong contrast among colorectal cancers, normal rectal wall and feces. (authors)

Basketball shot types and shot success in different levels of competitive basketball.

Directory of Open Access Journals (Sweden)

Frane Erčulj

Full Text Available The purpose of our research was to investigate the relative frequencies of different types of basketball shots (above head, hook shot, layup, dunk, tip-in, some details about their technical execution (one-legged, two-legged, drive, cut, …, and shot success in different levels of basketball competitions. We analysed video footage and categorized 5024 basketball shots from 40 basketball games and 5 different levels of competitive basketball (National Basketball Association (NBA, Euroleague, Slovenian 1st Division, and two Youth basketball competitions. Statistical analysis with hierarchical multinomial logistic regression models reveals that there are substantial differences between competitions. However, most differences decrease or disappear entirely after we adjust for differences in situations that arise in different competitions (shot location, player type, and attacks in transition. Differences after adjustment are mostly between the Senior and Youth competitions: more shots executed jumping or standing on one leg, more uncategorised shot types, and more dribbling or cutting to the basket in the Youth competitions, which can all be attributed to lesser technical and physical ability of developing basketball players. The two discernible differences within the Senior competitions are that, in the NBA, dunks are more frequent and hook shots are less frequent compared to European basketball, which can be attributed to better athleticism of NBA players. The effect situational variables have on shot types and shot success are found to be very similar for all competitions.

Basketball shot types and shot success in different levels of competitive basketball.

Science.gov (United States)

Erčulj, Frane; Štrumbelj, Erik

2015-01-01

The purpose of our research was to investigate the relative frequencies of different types of basketball shots (above head, hook shot, layup, dunk, tip-in), some details about their technical execution (one-legged, two-legged, drive, cut, …), and shot success in different levels of basketball competitions. We analysed video footage and categorized 5024 basketball shots from 40 basketball games and 5 different levels of competitive basketball (National Basketball Association (NBA), Euroleague, Slovenian 1st Division, and two Youth basketball competitions). Statistical analysis with hierarchical multinomial logistic regression models reveals that there are substantial differences between competitions. However, most differences decrease or disappear entirely after we adjust for differences in situations that arise in different competitions (shot location, player type, and attacks in transition). Differences after adjustment are mostly between the Senior and Youth competitions: more shots executed jumping or standing on one leg, more uncategorised shot types, and more dribbling or cutting to the basket in the Youth competitions, which can all be attributed to lesser technical and physical ability of developing basketball players. The two discernible differences within the Senior competitions are that, in the NBA, dunks are more frequent and hook shots are less frequent compared to European basketball, which can be attributed to better athleticism of NBA players. The effect situational variables have on shot types and shot success are found to be very similar for all competitions.

Hardware for quasi-single-shot multifrequency magnetic induction tomography (MIT): the Graz Mk2 system

International Nuclear Information System (INIS)

Scharfetter, H; Köstinger, A; Issa, S

2008-01-01

Magnetic induction tomography (MIT) has been suggested by several groups for the contact-less mapping of the passive electrical properties of tissues via AC magnetic fields in the frequency range between several tens of kHz and several tens of MHz. Multifrequency MIT as an analog to multifrequency EIT has been tried and first image reconstructions have been demonstrated with phantoms. MIT appears to yield comparable images to EIT but offers the advantage of being non-contacting. In the beta-dispersion range of most tissues the method is challenging because the signals are very small and buried in noise. In order to minimize drifts and systematic errors fast data acquisition is therefore pivotal. This paper presents a method for single-shot MIT which allows us to acquire the data for a multifrequency image with an analog bandwidth of 50 kHz–1.5 MHz which covers a good part of the β-dispersion of many tissues. The transmit (TX) coils are simultaneously driven by individual power amplifiers with a multisinus pattern with up to 3 A pp . The amplifiers are configured as current sources so as not to perturb the excitation fields by inappropriately terminated coils. The separation of the different TX channels after reception is achieved by splitting up the carrier frequencies into individual subcarriers with a narrow spacing of at most 300 Hz. In this way every TX coil is identifiable by its own subcarrier but the whole excitation band is contained within a few kHz. The real and imaginary parts of the received signals are extracted efficiently with FFT. The system noise and the sources for low-frequency perturbations are analyzed and characterized

Development of a single-shot-imaging thin film for an online Thomson parabola spectrometer

International Nuclear Information System (INIS)

Sakaki, H.; Fukuda, Y.; Nishiuchi, M.; Hori, T.; Yogo, A.; Jinno, S.; Kanasaki, M.; Niita, K.

2013-01-01

A single-shot-imaging thin scintillator film was developed for an online Thomson parabola (TP) spectrometer and the first analysis of laser accelerated ions, using the online TP spectrometer, was demonstrated at the JAEA-Kansai Advanced Relativistic Engineering Laser System (J-KAREN). An energy spectrum of ∼4.0 MeV protons is obtained using only this imaging film without the need of a microchannel plate that is typically utilized in online ion analyses. A general-purpose Monte Carlo particle and heavy ion-transport code system, which consists of various quantum dynamics models, was used for the prediction of the luminescent properties of the scintillator. The simulation can reasonably predict not only the ion trajectories detected by the spectrometer, but also luminescence properties.

Single shot fringe pattern phase demodulation using Hilbert-Huang transform aided by the principal component analysis.

Science.gov (United States)

Trusiak, Maciej; Służewski, Łukasz; Patorski, Krzysztof

2016-02-22

Hybrid single shot algorithm for accurate phase demodulation of complex fringe patterns is proposed. It employs empirical mode decomposition based adaptive fringe pattern enhancement (i.e., denoising, background removal and amplitude normalization) and subsequent boosted phase demodulation using 2D Hilbert spiral transform aided by the Principal Component Analysis method for novel, correct and accurate local fringe direction map calculation. Robustness to fringe pattern significant noise, uneven background and amplitude modulation as well as local fringe period and shape variations is corroborated by numerical simulations and experiments. Proposed automatic, adaptive, fast and comprehensive fringe analysis solution compares favorably with other previously reported techniques.

Single-photon sources

International Nuclear Information System (INIS)

Lounis, Brahim; Orrit, Michel

2005-01-01

The concept of the photon, central to Einstein's explanation of the photoelectric effect, is exactly 100 years old. Yet, while photons have been detected individually for more than 50 years, devices producing individual photons on demand have only appeared in the last few years. New concepts for single-photon sources, or 'photon guns', have originated from recent progress in the optical detection, characterization and manipulation of single quantum objects. Single emitters usually deliver photons one at a time. This so-called antibunching of emitted photons can arise from various mechanisms, but ensures that the probability of obtaining two or more photons at the same time remains negligible. We briefly recall basic concepts in quantum optics and discuss potential applications of single-photon states to optical processing of quantum information: cryptography, computing and communication. A photon gun's properties are significantly improved by coupling it to a resonant cavity mode, either in the Purcell or strong-coupling regimes. We briefly recall early production of single photons with atomic beams, and the operation principles of macroscopic parametric sources, which are used in an overwhelming majority of quantum-optical experiments. We then review the photophysical and spectroscopic properties and compare the advantages and weaknesses of various single nanometre-scale objects used as single-photon sources: atoms or ions in the gas phase and, in condensed matter, organic molecules, defect centres, semiconductor nanocrystals and heterostructures. As new generations of sources are developed, coupling to cavities and nano-fabrication techniques lead to improved characteristics, delivery rates and spectral ranges. Judging from the brisk pace of recent progress, we expect single photons to soon proceed from demonstrations to applications and to bring with them the first practical uses of quantum information

Single-shot electro-optic experiments for electron bunch diagnostics at Tsinghua Accelerator Laboratory

Energy Technology Data Exchange (ETDEWEB)

Wang, Wei; Du, Yingchao; Yan, Lixin; Hua, Jianfei; Zhang, Zhen; Zhou, Zheng [Accelerator Laboratory, Department of Engineering Physics, Tsinghua University, Beijing 100084 (China); Key Laboratory of Particle and Radiation Imaging, Tsinghua University, Ministry of Education, Beijing 100084 (China); Huang, Wenhui, E-mail: huangwh@mail.tsinghua.edu.cn [Accelerator Laboratory, Department of Engineering Physics, Tsinghua University, Beijing 100084 (China); Key Laboratory of Particle and Radiation Imaging, Tsinghua University, Ministry of Education, Beijing 100084 (China); Tang, Chuanxiang [Accelerator Laboratory, Department of Engineering Physics, Tsinghua University, Beijing 100084 (China); Key Laboratory of Particle and Radiation Imaging, Tsinghua University, Ministry of Education, Beijing 100084 (China); Li, Ming [Institute of Applied Electronics, China Academy of Engineering Physics, Mianyang 621900 (China)

2016-10-21

The electro-optic (EO) technique detects the Coulomb electric field distribution of relativistic electron bunches to obtain the associated longitudinal profile. This diagnostic method allows the direct time-resolved single-shot measurement and thus the real-time monitoring of the bunch profile and beam arrival time in a non-destructive way with sub-picosecond temporal resolution. In this paper, we report the measurement of the longitudinal profile of an electron bunch through electro-optic spectral decoding detection, in which the bunch profile is encoded into the spectra of the linearly chirped laser pulse. The experimental setup and measurement results of a 40 MeV electron bunch are presented, with a temporal profile length of 527 fs rms (~1.24 ps FWHM) and a beam arrival time jitter of 471 fs rms. Temporal resolution and future experimental improvement are also discussed.

Basketball Shot Types and Shot Success in Different Levels of Competitive Basketball

OpenAIRE

Er?ulj, Frane; ?trumbelj, Erik

2015-01-01

The purpose of our research was to investigate the relative frequencies of different types of basketball shots (above head, hook shot, layup, dunk, tip-in), some details about their technical execution (one-legged, two-legged, drive, cut, …), and shot success in different levels of basketball competitions. We analysed video footage and categorized 5024 basketball shots from 40 basketball games and 5 different levels of competitive basketball (National Basketball Association (NBA), Euroleague,...

Shot-by-shot spectrum model for rod-pinch, pulsed radiography machines

Directory of Open Access Journals (Sweden)

Wm M. Wood

2018-02-01

Full Text Available A simplified model of bremsstrahlung production is developed for determining the x-ray spectrum output of a rod-pinch radiography machine, on a shot-by-shot basis, using the measured voltage, V(t, and current, I(t. The motivation for this model is the need for an agile means of providing shot-by-shot spectrum prediction, from a laptop or desktop computer, for quantitative radiographic analysis. Simplifying assumptions are discussed, and the model is applied to the Cygnus rod-pinch machine. Output is compared to wedge transmission data for a series of radiographs from shots with identical target objects. Resulting model enables variation of parameters in real time, thus allowing for rapid optimization of the model across many shots. “Goodness of fit” is compared with output from LSP Particle-In-Cell code, as well as the Monte Carlo Neutron Propagation with Xrays (“MCNPX” model codes, and is shown to provide an excellent predictive representation of the spectral output of the Cygnus machine. Improvements to the model, specifically for application to other geometries, are discussed.

Shot-by-shot spectrum model for rod-pinch, pulsed radiography machines

Science.gov (United States)

Wood, Wm M.

2018-02-01

A simplified model of bremsstrahlung production is developed for determining the x-ray spectrum output of a rod-pinch radiography machine, on a shot-by-shot basis, using the measured voltage, V(t), and current, I(t). The motivation for this model is the need for an agile means of providing shot-by-shot spectrum prediction, from a laptop or desktop computer, for quantitative radiographic analysis. Simplifying assumptions are discussed, and the model is applied to the Cygnus rod-pinch machine. Output is compared to wedge transmission data for a series of radiographs from shots with identical target objects. Resulting model enables variation of parameters in real time, thus allowing for rapid optimization of the model across many shots. "Goodness of fit" is compared with output from LSP Particle-In-Cell code, as well as the Monte Carlo Neutron Propagation with Xrays ("MCNPX") model codes, and is shown to provide an excellent predictive representation of the spectral output of the Cygnus machine. Improvements to the model, specifically for application to other geometries, are discussed.

Buster-Jangle Shot Dog

International Nuclear Information System (INIS)

Kaul, Dean C.

1987-01-01

Shot Dog of the Buster-Jangle Series used a device which had a high-explosive configuration virtually identical to that of the Nagasaki bomb, though with different fissionable components. Dog was detonated at a height of 431.9 m with the mean atmospheric conditions between burst and ground being dry air density 1.027 mg/cc and atmospheric moisture density 0.006 mg/cc. The ground was taken to be that of Nevada test site (NTS) area 9 with a water content of 8% by weight. The yield of the weapon was 21 kt. Results shown here for Buster-Jangle Shot Dog have been scaled from those calculated for Ranger Shot Fox. The design features and burst geometries of the two devices were deemed sufficiently similar to make this substitution in the absence of a radiation leakage spectrum calculated explicitly for Buster-Jangle Shot Dog. However, while the relative atmospheric contents of the two shots were very similar, Shot Fox took place in air of approximately 10% greater density than Shot Dog. Thus, scaled calculated results could not be obtained to compare with the three closest measurement points at Shot Dog

Single-photon sources based on single molecules in solids

International Nuclear Information System (INIS)

Moerner, W E

2004-01-01

Single molecules in suitable host crystals have been demonstrated to be useful single-photon emitters both at liquid-helium temperatures and at room temperature. The low-temperature source achieved controllable emission of single photons from a single terrylene molecule in p-terphenyl by an adiabatic rapid passage technique. In contrast with almost all other single-molecule systems, terrylene single molecules show extremely high photostability under continuous, high-intensity irradiation. A room-temperature source utilizing this material has been demonstrated, in which fast pumping into vibrational sidebands of the electronically excited state achieved efficient inversion of the emissive level. This source yielded a single-photon emission probability p(1) of 0.86 at a detected count rate near 300 000 photons s -1 , with very small probability of emission of more than one photon. Thus, single molecules in solids can be considered as contenders for applications of single-photon sources such as quantum key distribution

Shot-to-shot reproducibility of a self-magnetically insulated ion diode

International Nuclear Information System (INIS)

Pushkarev, A. I.; Isakova, Yu. I.; Khailov, I. P.

2012-01-01

In this paper we present the analysis of shot to shot reproducibility of the ion beam which is formed by a self-magnetically insulated ion diode with an explosive emission graphite cathode. The experiments were carried out with the TEMP-4M accelerator operating in double-pulse mode: the first pulse is of negative polarity (300–500 ns, 100–150 kV), and this is followed by a second pulse of positive polarity (150 ns, 250–300 kV). The ion current density was 10–70 A/cm 2 depending on the diode geometry. The beam was composed from carbon ions (80%–85%) and protons. It was found that shot to shot variation in the ion current density was about 35%–40%, whilst the diode voltage and current were comparatively stable with the variation limited to no more than 10%. It was shown that focusing of the ion beam can improve the stability of the ion current generation and reduces the variation to 18%–20%. In order to find out the reason for the shot-to-shot variation in ion current density we examined the statistical correlation between the current density of the accelerated beam and other measured characteristics of the diode, such as the accelerating voltage, total current, and first pulse duration. The correlation between the ion current density measured simultaneously at different positions within the cross-section of the beam was also investigated. It was shown that the shot-to-shot variation in ion current density is mainly attributed to the variation in the density of electrons diffusing from the drift region into the A-K gap.

Allergy Shots (For Parents)

Science.gov (United States)

... Staying Safe Videos for Educators Search English Español Allergy Shots KidsHealth / For Parents / Allergy Shots What's in ... to help a child deal with them. Why Allergy Shots Are Used An allergy occurs when the ...

Real time quantitative phase microscopy based on single-shot transport of intensity equation (ssTIE) method

Science.gov (United States)

Yu, Wei; Tian, Xiaolin; He, Xiaoliang; Song, Xiaojun; Xue, Liang; Liu, Cheng; Wang, Shouyu

2016-08-01

Microscopy based on transport of intensity equation provides quantitative phase distributions which opens another perspective for cellular observations. However, it requires multi-focal image capturing while mechanical and electrical scanning limits its real time capacity in sample detections. Here, in order to break through this restriction, real time quantitative phase microscopy based on single-shot transport of the intensity equation method is proposed. A programmed phase mask is designed to realize simultaneous multi-focal image recording without any scanning; thus, phase distributions can be quantitatively retrieved in real time. It is believed the proposed method can be potentially applied in various biological and medical applications, especially for live cell imaging.

Accelerator-based single-shot ultrafast transmission electron microscope with picosecond temporal resolution and nanometer spatial resolution

Science.gov (United States)

Xiang, D.; Fu, F.; Zhang, J.; Huang, X.; Wang, L.; Wang, X.; Wan, W.

2014-09-01

We present feasibility study of an accelerator-based ultrafast transmission electron microscope (u-TEM) capable of producing a full field image in a single-shot with simultaneous picosecond temporal resolution and nanometer spatial resolution. We study key physics related to performance of u-TEMs and discuss major challenges as well as possible solutions for practical realization of u-TEMs. The feasibility of u-TEMs is confirmed through simulations using realistic electron beam parameters. We anticipate that u-TEMs with a product of temporal and spatial resolution beyond 10-19 ms will open up new opportunities in probing matter at ultrafast temporal and ultrasmall spatial scales.

Intra-shot MSE Calibration Technique For LHCD Experiments

International Nuclear Information System (INIS)

Ko, Jinseok; Scott, Steve; Shiraiwa, Syun'ichi; Greenwald, Martin; Parker, Ronald; Wallace, Gregory

2009-01-01

The spurious drift in pitch angle of order several degrees measured by the Motional Stark Effect (MSE) diagnostic in the Alcator C-Mod tokamak1 over the course of an experimental run day has precluded direct utilization of independent absolute calibrations. Recently, the underlying cause of the drift has been identified as thermal stress-induced birefringence in a set of in-vessel lenses. The shot-to-shot drift can be avoided by using MSE to measure only the change in pitch angle between a reference phase and a phase of physical interest within a single plasma discharge. This intra-shot calibration technique has been applied to the Lower Hybrid Current Drive (LHCD) experiments and the measured current profiles qualitatively demonstrate several predictions of LHCD theory such as an inverse dependence of current drive efficiency on the parallel refractive index and the presence of off-axis current drive.

Highly Resolved Mg/Ca Depth Profiles of Planktic Foraminifer test Walls Using Single shot Measurements of fs-LA-ICPMS

Science.gov (United States)

Jochum, K. P.; Schiebel, R.; Stoll, B.; Weis, U.; Haug, G. H.

2017-12-01

Foraminifers are sensitive archives of changes in climate and marine environment. It has been shown that the Mg/Ca signal is a suitable proxy of seawater temperature, because the incorporation of Mg depends on ambient water temperature. In contrast to most former studies, where this ratio is determined by solution-based bulk analysis of 20 - 30 specimens, we have investigated Mg/Ca in single specimens and single chambers at high resolution. A new fs-200 nm-LA-ICPMS technique was developed for the µm-sized layered calcite shells. To generate depth profiles with a resolution of about 50 nm/shot, we chose a low fluence of about 0.3 Jcm-2 and performed single shot measurements of the double charged 44Ca++ and the single charged 25Mg+ ions together. Precision (RSD) of the Mg/Ca data is about 5 %. Calibration was performed with the carbonate reference material MACS-3 from the USGS. Our results for different species from the Arabian Sea and Caribbean Sea demonstrate that Mg/Ca of different chambers vary and indicate that the foraminifer individuals built their chambers in different water depths and/or experienced seasonal changes in seawater temperature caused, for example, by upwelling (cold) versus stratified (warm) conditions. Typically, the Mg/Ca ratios of the final two chambers of the planktic foraminifer Globorotalia menardii from a sediment core of the Arabian Sea differ by about 5 mmol/mol from earlier chambers (2 mmol/mol) corresponding to seawater temperatures of 28 °C and 18 °C, respectively. In addition, mass fractions of other elements like Sr, Mn, Fe, Ba, and U have been determined with fs-LA-ICPMS using fast line scans, and thus provide further insights in the ecology of foraminifers.

Generalised shot noise Cox processes

DEFF Research Database (Denmark)

Møller, Jesper; Torrisi, Giovanni Luca

2005-01-01

We introduce a class of cox cluster processes called generalised shot noise Cox processes (GSNCPs), which extends the definition of shot noise Cox processes (SNCPs) in two directions: the point process that drives the shot noise is not necessarily Poisson, and the kernel of the shot noise can...

Optimization And Single-Shot Characterization Of Ultrashort Thz Pulses From A Laser Wakefield Accelerator

International Nuclear Information System (INIS)

Plateau, G.R.; Matlis, N.H.; van Tilborg, J.; Geddes, C.G.R.; Toth, Cs.; Schroeder, C.B.; Leemans, W.P.

2009-01-01

We present spatiotemporal characterization of μJ-class ultrashort THz pulses generated from a laser wakefield accelerator (LWFA). Accelerated electrons, resulting from the interaction of a high-intensity laser pulse with a plasma, emit high-intensity THz pulses as coherent transition radiation. Such high peak-power THz pulses, suitable for high-field (MV/cm) pump-probe experiments, also provide a non-invasive bunch-length diagnostic and thus feedback for the accelerator. The characterization of the THz pulses includes energy measurement using a Golay cell, 2D sign-resolved electro-optic measurement and single-shot spatiotemporal electric-field distribution retrieval using a new technique, coined temporal electric-field cross-Correlation (TEX). All three techniques corroborate THz pulses of ∼ 5 μJ, with peak fields of 100's of kV/cm and ∼ 0.4 ps rms duration.

Single-shot femtosecond laser ablation of gold surface in air and isopropyl alcohol

Science.gov (United States)

Kudryashov, S. I.; Saraeva, I. N.; Lednev, V. N.; Pershin, S. M.; Rudenko, A. A.; Ionin, A. A.

2018-05-01

Single-shot IR femtosecond-laser ablation of gold surfaces in ambient air and liquid isopropyl alcohol was studied by scanning electron microscopy characterization of crater topographies and time-resolved optical emission spectroscopy of ablative plumes in regimes, typical for non-filamentary and non-fragmentation laser production of nanoparticle sols. Despite one order of magnitude shorter (few nanoseconds) lifetimes and almost two orders of magnitude lower intensities of the quenched ablative plume emission in the alcohol ambient at the same peak laser fluence, craters for the dry and wet conditions appeared with rather similar nanofoam-like spallative topographies and the same thresholds. These facts envision the underlying surface spallation as one of the basic ablation mechanisms relevant for both dry and wet advanced femtosecond laser surface nano/micro-machining and texturing, as well as for high-throughput femtosecond laser ablative production of colloidal nanoparticles by MHz laser-pulse trains via their direct nanoscale jetting from the nanofoam in air and fluid environments.

Characterization of temporal coherence of hard X-ray free-electron laser pulses with single-shot interferograms

Directory of Open Access Journals (Sweden)

Taito Osaka

2017-11-01

Full Text Available Temporal coherence is one of the most fundamental characteristics of light, connecting to spectral information through the Fourier transform relationship between time and frequency. Interferometers with a variable path-length difference (PLD between the two branches have widely been employed to characterize temporal coherence properties for broad spectral regimes. Hard X-ray interferometers reported previously, however, have strict limitations in their operational photon energies, due to the specific optical layouts utilized to satisfy the stringent requirement for extreme stability of the PLD at sub-ångström scales. The work presented here characterizes the temporal coherence of hard X-ray free-electron laser (XFEL pulses by capturing single-shot interferograms. Since the stability requirement is drastically relieved with this approach, it was possible to build a versatile hard X-ray interferometer composed of six separate optical elements to cover a wide photon energy range from 6.5 to 11.5 keV while providing a large variable delay time of up to 47 ps at 10 keV. A high visibility of up to 0.55 was observed at a photon energy of 10 keV. The visibility measurement as a function of time delay reveals a mean coherence time of 5.9 ± 0.7 fs, which agrees with that expected from the single-shot spectral information. This is the first result of characterizing the temporal coherence of XFEL pulses in the hard X-ray regime and is an important milestone towards ultra-high energy resolutions at micro-electronvolt levels in time-domain X-ray spectroscopy, which will open up new opportunities for revealing dynamic properties in diverse systems on timescales from femtoseconds to nanoseconds, associated with fluctuations from ångström to nanometre spatial scales.

Sequential interactions-in which one player plays first and another responds-promote cooperation in evolutionary-dynamical simulations of single-shot Prisoner's Dilemma and Snowdrift games.

Science.gov (United States)

Laird, Robert A

2018-05-21

Cooperation is a central topic in evolutionary biology because (a) it is difficult to reconcile why individuals would act in a way that benefits others if such action is costly to themselves, and (b) it underpins many of the 'major transitions of evolution', making it essential for explaining the origins of successively higher levels of biological organization. Within evolutionary game theory, the Prisoner's Dilemma and Snowdrift games are the main theoretical constructs used to study the evolution of cooperation in dyadic interactions. In single-shot versions of these games, wherein individuals play each other only once, players typically act simultaneously rather than sequentially. Allowing one player to respond to the actions of its co-player-in the absence of any possibility of the responder being rewarded for cooperation or punished for defection, as in simultaneous or sequential iterated games-may seem to invite more incentive for exploitation and retaliation in single-shot games, compared to when interactions occur simultaneously, thereby reducing the likelihood that cooperative strategies can thrive. To the contrary, I use lattice-based, evolutionary-dynamical simulation models of single-shot games to demonstrate that under many conditions, sequential interactions have the potential to enhance unilaterally or mutually cooperative outcomes and increase the average payoff of populations, relative to simultaneous interactions-benefits that are especially prevalent in a spatially explicit context. This surprising result is attributable to the presence of conditional strategies that emerge in sequential games that can't occur in the corresponding simultaneous versions. Copyright © 2018 Elsevier Ltd. All rights reserved.

Single photon sources with single semiconductor quantum dots

Science.gov (United States)

Shan, Guang-Cun; Yin, Zhang-Qi; Shek, Chan Hung; Huang, Wei

2014-04-01

In this contribution, we briefly recall the basic concepts of quantum optics and properties of semiconductor quantum dot (QD) which are necessary to the understanding of the physics of single-photon generation with single QDs. Firstly, we address the theory of quantum emitter-cavity system, the fluorescence and optical properties of semiconductor QDs, and the photon statistics as well as optical properties of the QDs. We then review the localization of single semiconductor QDs in quantum confined optical microcavity systems to achieve their overall optical properties and performances in terms of strong coupling regime, efficiency, directionality, and polarization control. Furthermore, we will discuss the recent progress on the fabrication of single photon sources, and various approaches for embedding single QDs into microcavities or photonic crystal nanocavities and show how to extend the wavelength range. We focus in particular on new generations of electrically driven QD single photon source leading to high repetition rates, strong coupling regime, and high collection efficiencies at elevated temperature operation. Besides, new developments of room temperature single photon emission in the strong coupling regime are reviewed. The generation of indistinguishable photons and remaining challenges for practical single-photon sources are also discussed.

Birth Control Shot

Science.gov (United States)

... Health Food & Fitness Diseases & Conditions Infections Drugs & Alcohol School & Jobs Sports Expert Answers (Q&A) Staying Safe Videos for Educators Search English Español Birth Control Shot KidsHealth / For Teens / Birth Control Shot What's ...

One-Shot Learning of Human Activity With an MAP Adapted GMM and Simplex-HMM.

Science.gov (United States)

Rodriguez, Mario; Orrite, Carlos; Medrano, Carlos; Makris, Dimitrios

2016-05-10

This paper presents a novel activity class representation using a single sequence for training. The contribution of this representation lays on the ability to train an one-shot learning recognition system, useful in new scenarios where capturing and labeling sequences is expensive or impractical. The method uses a universal background model of local descriptors obtained from source databases available on-line and adapts it to a new sequence in the target scenario through a maximum a posteriori adaptation. Each activity sample is encoded in a sequence of normalized bag of features and modeled by a new hidden Markov model formulation, where the expectation-maximization algorithm for training is modified to deal with observations consisting in vectors in a unit simplex. Extensive experiments in recognition have been performed using one-shot learning over the public datasets Weizmann, KTH, and IXMAS. These experiments demonstrate the discriminative properties of the representation and the validity of application in recognition systems, achieving state-of-the-art results.

Optical properties (bidirectional reflectance distribution function) of shot fabric.

Science.gov (United States)

Lu, R; Koenderink, J J; Kappers, A M

2000-11-01

To study the optical properties of materials, one needs a complete set of the angular distribution functions of surface scattering from the materials. Here we present a convenient method for collecting a large set of bidirectional reflectance distribution function (BRDF) samples in the hemispherical scattering space. Material samples are wrapped around a right-circular cylinder and irradiated by a parallel light source, and the scattered radiance is collected by a digital camera. We tilted the cylinder around its center to collect the BRDF samples outside the plane of incidence. This method can be used with materials that have isotropic and anisotropic scattering properties. We demonstrate this method in a detailed investigation of shot fabrics. The warps and the fillings of shot fabrics are dyed different colors so that the fabric appears to change color at different viewing angles. These color-changing characteristics are found to be related to the physical and geometrical structure of shot fabric. Our study reveals that the color-changing property of shot fabrics is due mainly to an occlusion effect.

Centrifugal shot blast system

International Nuclear Information System (INIS)

1998-02-01

This report describes a demonstration of Concrete cleaning, Inc., modified centrifugal shot blast technology to remove the paint coating from concrete flooring. This demonstration is part of the Chicago Pile-5 (CP-5) Large-Scale Demonstration Project (LSDP) sponsored by the US Department of Energy (DOE), office of Science and Technology (OST), Deactivation and Decommissioning Focus Area (DDFA). The objective of the LSDP is to select and demonstrate potentially beneficial technologies at the Argonne National Laboratory-East (ANL) CP-5 Research Reactor. The purpose of the LSDP is to demonstrate that using innovative and improved decontamination and decommissioning (D and D) technologies from various sources can result in significant benefits, such as decreased cost and increased health and safety, as compared with baseline D and D technologies. Potential markets exist for the innovative centrifugal shot blast system at the following sites: Fernald Environmental Management Project, Los Alamos, Nevada, Oak Ridge Y-12 and K-25, Paducah, Portsmouth Gaseous Diffusion site, and the Savannah River Site. This information is based on a revision to the OST Linkage Tables dated August 4, 1997

Characteristics of magnetically insulated diode in a multi-shot operation

Energy Technology Data Exchange (ETDEWEB)

Chishiro, E; Masugata, K; Yatsui, K [Nagaoka Univ. of Technology (Japan). Laboratory of Beam Technology

1997-12-31

The beam characteristics in a multi-shot operation were evaluated. The MID utilized in the experiment is a racetrack type diode, where flat anode and cathode electrodes are utilized. On the anode, a polyethylene sheet of 1 mm thickness is attached as an ion source. The MID is successively operated without breaking the vacuum. An ion current density (J{sub i}) of 350 A/cm{sup 2} is observed at the first shot when the diode gap is 5 mm. The value decreases with increasing number of shots and at the 7th shot, J{sub i} is less than 150 A/cm{sup 2}. After 7 shots, the anode surface is inspected and found to be covered with stuck matter of metallic materials such as Zn, Al, Fe, Cu. These materials seem to be produced by the ablation of the MID electrode. By eliminating the stuck matter from the surface, J{sub i} is recovered to the initial value. The decrease in J{sub i} is due to the fact that the anode is covered with the stuck matter, which prevents the growth of anode plasma. (author). 6 figs., 8 refs.

Single-shot spectro-temporal characterization of XUV pulses from a seeded free-electron laser

Science.gov (United States)

de Ninno, Giovanni; Gauthier, David; Mahieu, Benoît; Ribič, Primož Rebernik; Allaria, Enrico; Cinquegrana, Paolo; Danailov, Miltcho Bojanov; Demidovich, Alexander; Ferrari, Eugenio; Giannessi, Luca; Penco, Giuseppe; Sigalotti, Paolo; Stupar, Matija

2015-08-01

Intense ultrashort X-ray pulses produced by modern free-electron lasers (FELs) allow one to probe biological systems, inorganic materials and molecular reaction dynamics with nanoscale spatial and femtoscale temporal resolution. These experiments require the knowledge, and possibly the control, of the spectro-temporal content of individual pulses. FELs relying on seeding have the potential to produce spatially and temporally fully coherent pulses. Here we propose and implement an interferometric method, which allows us to carry out the first complete single-shot spectro-temporal characterization of the pulses, generated by an FEL in the extreme ultraviolet spectral range. Moreover, we provide the first direct evidence of the temporal coherence of a seeded FEL working in the extreme ultraviolet spectral range and show the way to control the light generation process to produce Fourier-limited pulses. Experiments are carried out at the FERMI FEL in Trieste.

Fast Detection of Airports on Remote Sensing Images with Single Shot MultiBox Detector

Science.gov (United States)

Xia, Fei; Li, HuiZhou

2018-01-01

This paper introduces a method for fast airport detection on remote sensing images (RSIs) using Single Shot MultiBox Detector (SSD). To our knowledge, this could be the first study which introduces an end-to-end detection model into airport detection on RSIs. Based on the common low-level features between natural images and RSIs, a convolution neural network trained on large amounts of natural images was transferred to tackle the airport detection problem with limited annotated data. To deal with the specific characteristics of RSIs, some related parameters in the SSD, such as the scales and layers, were modified for more accurate and rapider detection. The experiments show that the proposed method could achieve 83.5% Average Recall at 8 FPS on RSIs with the size of 1024*1024. In contrast to Faster R-CNN, an improvement on AP and speed could be obtained.

Anti-spoof touchless 3D fingerprint recognition system using single shot fringe projection and biospeckle analysis

Science.gov (United States)

Chatterjee, Amit; Bhatia, Vimal; Prakash, Shashi

2017-08-01

Fingerprint is a unique, un-alterable and easily collected biometric of a human being. Although it is a 3D biological characteristic, traditional methods are designed to provide only a 2D image. This touch based mapping of 3D shape to 2D image losses information and leads to nonlinear distortions. Moreover, as only topographic details are captured, conventional systems are potentially vulnerable to spoofing materials (e.g. artificial fingers, dead fingers, false prints, etc.). In this work, we demonstrate an anti-spoof touchless 3D fingerprint detection system using a combination of single shot fringe projection and biospeckle analysis. For fingerprint detection using fringe projection, light from a low power LED source illuminates a finger through a sinusoidal grating. The fringe pattern modulated because of features on the fingertip is captured using a CCD camera. Fourier transform method based frequency filtering is used for the reconstruction of 3D fingerprint from the captured fringe pattern. In the next step, for spoof detection using biospeckle analysis a visuo-numeric algorithm based on modified structural function and non-normalized histogram is proposed. High activity biospeckle patterns are generated because of interaction of collimated laser light with internal fluid flow of the real finger sample. This activity reduces abruptly in case of layered fake prints, and is almost absent in dead or fake fingers. Furthermore, the proposed setup is fast, low-cost, involves non-mechanical scanning and is highly stable.

The importance of reliability to the SunShot Initiative (Presentation Recording)

Science.gov (United States)

Jones-Albertus, Rebecca

2015-09-01

The U.S. Department of Energy's SunShot Initiative was launched in 2011 to make subsidy-free solar electricity cost competitive with conventional energy sources by the end of the decade. Research in reliability can play a major role in realizing the SunShot goal of 0.06/kWh. By improving photovoltaic module lifetime and reducing degradation rates, a system's lifetime energy output is increased. Increasing confidence in photovoltaic performance prediction can lower perceived investment risk and thus the cost of capital. Accordingly, in 2015, SunShot expects to award more than $40 million through its SunShot National Laboratory Multiyear Partnership (SuNLaMP) and Physics of Reliability: Evaluating Design Insights for Component Technologies in Solar (PREDICTS) 2 funding programs, for research into reliability topics such as determining acceleration factors, modeling degradation rates and failure mechanisms, improving predictive performance models, and developing new test methods and instrumentation.

Neural computations mediating one-shot learning in the human brain.

Directory of Open Access Journals (Sweden)

Sang Wan Lee

2015-04-01

Full Text Available Incremental learning, in which new knowledge is acquired gradually through trial and error, can be distinguished from one-shot learning, in which the brain learns rapidly from only a single pairing of a stimulus and a consequence. Very little is known about how the brain transitions between these two fundamentally different forms of learning. Here we test a computational hypothesis that uncertainty about the causal relationship between a stimulus and an outcome induces rapid changes in the rate of learning, which in turn mediates the transition between incremental and one-shot learning. By using a novel behavioral task in combination with functional magnetic resonance imaging (fMRI data from human volunteers, we found evidence implicating the ventrolateral prefrontal cortex and hippocampus in this process. The hippocampus was selectively "switched" on when one-shot learning was predicted to occur, while the ventrolateral prefrontal cortex was found to encode uncertainty about the causal association, exhibiting increased coupling with the hippocampus for high-learning rates, suggesting this region may act as a "switch," turning on and off one-shot learning as required.

Flexible Low-power SiGe HBT Amplifier Circuits for Fast Single-shot Spin Readout

Science.gov (United States)

England, Troy; Lilly, Michael; Curry, Matthew; Carr, Stephen; Carroll, Malcolm

Fast, low-power quantum state readout is one of many challenges facing quantum information processing. Single electron transistors (SETs) are potentially fast, sensitive detectors for performing spin readout of electrons bound to Si:P donors. From a circuit perspective, however, their output impedance and nonlinear conductance are ill suited to drive the parasitic capacitance of coaxial conductors used in cryogenic environments, necessitating a cryogenic amplification stage. We will introduce two new amplifier topologies that provide excellent gain versus power tradeoffs using silicon-germanium (SiGe) heterojunction bipolar transistors (HBTs). The AC HBT allows in-situ adjustment of power dissipation during an experiment and can provide gain in the millikelvin temperature regime while dissipating less than 500 nW. The AC Current Amplifier maximizes gain at nearly 800 A/A. We will also show results of using these amplifiers with SETs at 4 K. This work was performed, in part, at the Center for Integrated Nanotechnologies, a U.S. DOE Office of Basic Energy Sciences user facility. Sandia National Laboratories is a multi-program laboratory operated by Sandia Corporation, a Lockheed-Martin Company, for the U. S. Department of Energy under Contract No. DE-AC04-94AL85000. Flexible Low-power SiGe HBT Amplifier Circuits for Fast Single-shot Spin Readout.

Shot Automation for the National Ignition Facility

International Nuclear Information System (INIS)

Lagin, L J; Bettenhausen, R C; Beeler, R G; Bowers, G A; Carey, R.; Casavant, D.D.; Cline, B.D.; Demaret, R.D.; Domyancic, D.M.; Elko, S.D.; Fisher, J.M.; Hermann, M.R.; Krammen, J.E.; Kohut, T.R.; Marshall, C.D.; Mathisen, D.G.; Ludwigsen, A.P.; Patterson, Jr. R.W.; Sanchez, R.J.; Stout, E.A.; Van Arsdall, P.J.; Van Wonterghem, B.M.

2005-01-01

A shot automation framework has been developed and deployed during the past year to automate shots performed on the National Ignition Facility (NIF) using the Integrated Computer Control System This framework automates a 4-8 hour shot sequence, that includes inputting shot goals from a physics model, set up of the laser and diagnostics, automatic alignment of laser beams and verification of status. This sequence consists of set of preparatory verification shots, leading to amplified system shots using a 4-minute countdown, triggering during the last 2 seconds using a high-precision timing system, followed by post-shot analysis and archiving. The framework provides for a flexible, model-based execution driven of scriptable automation called macro steps. The framework is driven by high-level shot director software that provides a restricted set of shot life cycle state transitions to 25 collaboration supervisors that automate 8-laser beams (bundles) and a common set of shared resources. Each collaboration supervisor commands approximately 10 subsystem shot supervisors that perform automated control and status verification. Collaboration supervisors translate shot life cycle state commands from the shot director into sequences of ''macro steps'' to be distributed to each of its shot supervisors. Each Shot supervisor maintains order of macro steps for each subsystem and supports collaboration between macro steps. They also manage failure, restarts and rejoining into the shot cycle (if necessary) and manage auto/manual macro step execution and collaborations between other collaboration supervisors. Shot supervisors execute macro step shot functions commanded by collaboration supervisors. Each macro step has database-driven verification phases and a scripted perform phase. This provides for a highly flexible methodology for performing a variety of NIF shot types. Database tables define the order of work and dependencies (workflow) of macro steps to be performed for a

Single-shot full resolution region-of-interest (ROI) reconstruction in image plane digital holographic microscopy

Science.gov (United States)

Singh, Mandeep; Khare, Kedar

2018-05-01

We describe a numerical processing technique that allows single-shot region-of-interest (ROI) reconstruction in image plane digital holographic microscopy with full pixel resolution. The ROI reconstruction is modelled as an optimization problem where the cost function to be minimized consists of an L2-norm squared data fitting term and a modified Huber penalty term that are minimized alternately in an adaptive fashion. The technique can provide full pixel resolution complex-valued images of the selected ROI which is not possible to achieve with the commonly used Fourier transform method. The technique can facilitate holographic reconstruction of individual cells of interest from a large field-of-view digital holographic microscopy data. The complementary phase information in addition to the usual absorption information already available in the form of bright field microscopy can make the methodology attractive to the biomedical user community.

High human exposure to lead through consumption of birds hunted with lead shot

International Nuclear Information System (INIS)

Johansen, P.; Asmund, G.; Riget, F.

2004-01-01

Lead shot contaminates the edible parts of birds so that tolerable human lead intake is exceeded. - We assess lead contamination of Greenland seabirds killed with lead shot having studied thick-billed murre and common eider, the two most important species in the diet. The lead concentration is very high in meat of eiders killed with lead shot (mean 6.1 μg/g-wet wt, 95% CL 2.1-12). This level is about 44 times higher than in drowned eiders and eight times higher than in shot murres. Analyzing whole breasts instead of sub-samples reveals about seven times higher lead levels in birds' meat. We conclude that in some cases the lead intake by Greenland bird eaters will largely exceed the FAO/WHO tolerable lead intake guideline and that lead shot is a more important source of lead in the diet than previously estimated

Kinematic MRI using short TR single shot fast spin echo (SSFSE) in evaluating swallowing

Energy Technology Data Exchange (ETDEWEB)

Isogai, Satoshi; Takehara, Yasuo; Isoda, Haruo; Kodaira, Nami; Masunaga, Hatsuko; Ozawa, Fukujirou; Kaneko, Masao [Hamamatsu Univ. School of Medicine, Shizuoka (Japan); Nozaki, Atsushi; Kabasawa, Hiroyuki

1999-03-01

The utility of short TR single shot fast spin echo (SSFSE) MR imaging for evaluating swallowing was determined. Five healthy volunteers underwent kinematic MR imaging of swallowing with a 1.5 T MR scanner using the short TR (300 ms) SSFSE sequence. Twenty phases of sagittal sections were acquired within 6 sec, where the temporal resolution was 300 ms. For oral contrast medium, we used prune yogurt juice with Fe added. The image contrast of short TR SSFSE was found to be somewhere like that of T1-weighted images. In all cases, both the buccal and pharyngeal stages of swallowing were successfully depicted. The Fe-added prune yogurt juice performed as a positive contrast medium and helped determine anatomical structures in the buccal stage. Short TR (300 ms) SSFSE was useful in evaluating swallowing. The combined use of Fe-added prune yogurt juice was helpful in enhancing the surface of the oropharynx. (author)

Kinematic MRI using short TR single shot fast spin echo (SSFSE) in evaluating swallowing

International Nuclear Information System (INIS)

Isogai, Satoshi; Takehara, Yasuo; Isoda, Haruo; Kodaira, Nami; Masunaga, Hatsuko; Ozawa, Fukujirou; Kaneko, Masao; Nozaki, Atsushi; Kabasawa, Hiroyuki

1999-01-01

The utility of short TR single shot fast spin echo (SSFSE) MR imaging for evaluating swallowing was determined. Five healthy volunteers underwent kinematic MR imaging of swallowing with a 1.5 T MR scanner using the short TR (300 ms) SSFSE sequence. Twenty phases of sagittal sections were acquired within 6 sec, where the temporal resolution was 300 ms. For oral contrast medium, we used prune yogurt juice with Fe added. The image contrast of short TR SSFSE was found to be somewhere like that of T1-weighted images. In all cases, both the buccal and pharyngeal stages of swallowing were successfully depicted. The Fe-added prune yogurt juice performed as a positive contrast medium and helped determine anatomical structures in the buccal stage. Short TR (300 ms) SSFSE was useful in evaluating swallowing. The combined use of Fe-added prune yogurt juice was helpful in enhancing the surface of the oropharynx. (author)

LiNbO/sub 3/:Ti directional-coupler modulators for high-bandwidth, single-shot instrumentation systems operating at 800 nm

International Nuclear Information System (INIS)

Lowry, M.; Jander, D.; Lancaster, G.; Kwiat, P.; McWright, G.; Peterson, R.T.; Tindall, W.; Roeske, F.

1987-01-01

The authors update their work on optical directional-coupler modulators (ODCMs) for single-shot, analog instrumentation systems operating at -- 800 nm. They can now fabricate directional-coupler devices that have one input and two output pigtails with insertion losses of 8.9 dB on average. Data for the ODCMs indicate an impulse response of less than 40 ps. They have implemented these devices in an ultrafast, x-ray measurement system. They discuss our data from this implementation and their implications for continued ODCM development

Clinical application of Half Fourier Acquisition Single Shot Turbo Spin Echo (HASTE) imaging accelerated by simultaneous multi-slice acquisition.

Science.gov (United States)

Schulz, Jenni; P Marques, José; Ter Telgte, Annemieke; van Dorst, Anouk; de Leeuw, Frank-Erik; Meijer, Frederick J A; Norris, David G

2018-01-01

As a single-shot sequence with a long train of refocusing pulses, Half-Fourier Acquisition Single-Shot Turbo-Spin-Echo (HASTE) suffers from high power deposition limiting use at high resolutions and high field strengths, particularly if combined with acceleration techniques such as simultaneous multi-slice (SMS) imaging. Using a combination of multiband (MB)-excitation and PINS-refocusing pulses will effectively accelerate the acquisition time while staying within the SAR limitations. In particular, uncooperative and young patients will profit from the speed of the MB-PINS HASTE sequence, as clinical diagnosis can be possible without sedation. Materials and MethodsMB-excitation and PINS-refocusing pulses were incorporated into a HASTE-sequence with blipped CAIPIRINHA and TRAPS including an internal FLASH reference scan for online reconstruction. Whole brain MB-PINS HASTE data were acquired on a Siemens 3T-Prisma system from 10 individuals and compared to a clinical HASTE protocol. ResultsThe proposed MB-PINS HASTE protocol accelerates the acquisition by about a factor 2 compared to the clinical HASTE. The diagnostic image quality proved to be comparable for both sequences for the evaluation of the overall aspect of the brain, the detection of white matter changes and areas of tissue loss, and for the evaluation of the CSF spaces although artifacts were more frequently encountered with MB-PINS HASTE. ConclusionsMB-PINS HASTE enables acquisition of slice accelerated highly T2-weighted images and provides good diagnostic image quality while reducing acquisition time. Copyright © 2017 Elsevier B.V. All rights reserved.

The single-shot opto-digitizer; L'optoechantillonneur monocoup

Energy Technology Data Exchange (ETDEWEB)

Nail, M.; Gibert, Ph. [CEA/DAM-Ile de France, Dept. de Conception et Realisation des Experimentations (DCRE), 91 - Bruyeres-le-Chatel (France); CEA/DAM-Ile de France, Dept. Laser Puissance, DLP, 91 - Bruyeres-Le-Chatel (France)

2000-07-01

Laser-plasma experiments need to measure signals provided either by X-ray, photonic or neutronic detector. The measurement should have 50 GHz bandwidth and up to several hundred of Giga-Hertz for sub picosecond plasmas. For this purpose, a 35 GHz single shot opto-digitizer (10 ps risetime) has been studied and built. The device is made up of a 50 ohms microstrip propagation line, periodically lined by 100 sampled gates. The propagation line is long enough to measure a 400 ps duration. The sampling rate is 250 Gsa/s (every 4 ps). The sampled gates are made with fast recombining photo-material and turn on by a subpicosecond laser pulse which is synchronized exactly with the analysed phenomena. Every gate is recording to a storing capacitor. After the recording, every capacitor charge is needed to built the signal that was displayed on the propagation line. The dynamic range of measurement is 47 for the entire device. The device can measure positive or negative signals from 1.5 to 70 Volts. To increase the bandwidth, two another kinds of opto-digitizer were studied: one is a buried stripline with 56 GHz band width, the other a 70 GHz coplanar transmission line. For the purpose of subpicosecond plasmas, a 30 coplanar waveguide opto-digitizer was studied. Characteristics are as followed: window of measurement 40 ps, sampling rate 1 ps, bandwidth 230 GHz. Finally, a bundle of optical fibers was used to propagate the laser beam on semiconductor gates. If the gates are lighted at the same time, i.e. if the optical fibers have the same length, we get a simultaneous addressing. By using different lengths of optical fibers, we can do a sequential addressing. So, the sampling rate becomes a combination of the distance between two adjacent sampled channels, and the difference in length of optical fibers. (author)

Ranking TEM cameras by their response to electron shot noise

International Nuclear Information System (INIS)

Grob, Patricia; Bean, Derek; Typke, Dieter; Li, Xueming; Nogales, Eva; Glaeser, Robert M.

2013-01-01

We demonstrate two ways in which the Fourier transforms of images that consist solely of randomly distributed electrons (shot noise) can be used to compare the relative performance of different electronic cameras. The principle is to determine how closely the Fourier transform of a given image does, or does not, approach that of an image produced by an ideal camera, i.e. one for which single-electron events are modeled as Kronecker delta functions located at the same pixels where the electrons were incident on the camera. Experimentally, the average width of the single-electron response is characterized by fitting a single Lorentzian function to the azimuthally averaged amplitude of the Fourier transform. The reciprocal of the spatial frequency at which the Lorentzian function falls to a value of 0.5 provides an estimate of the number of pixels at which the corresponding line-spread function falls to a value of 1/e. In addition, the excess noise due to stochastic variations in the magnitude of the response of the camera (for single-electron events) is characterized by the amount to which the appropriately normalized power spectrum does, or does not, exceed the total number of electrons in the image. These simple measurements provide an easy way to evaluate the relative performance of different cameras. To illustrate this point we present data for three different types of scintillator–coupled camera plus a silicon-pixel (direct detection) camera. - Highlights: ► Fourier amplitude spectra of noise are well fitted by a single Lorentzian. ► This measures how closely, or not, the response approaches the single-pixel ideal. ► Noise in the Fourier amplitudes is (1−π/4) times the shot noise power spectrum. ► Finite variance in the single-electron responses adds to the output noise. ► This excess noise may be equal to or greater than shot noise itself

Stutter seismic source

Energy Technology Data Exchange (ETDEWEB)

Gumma, W. H.; Hughes, D. R.; Zimmerman, N. S.

1980-08-12

An improved seismic prospecting system comprising the use of a closely spaced sequence of source initiations at essentially the same location to provide shorter objective-level wavelets than are obtainable with a single pulse. In a preferred form, three dynamite charges are detonated in the same or three closely spaced shot holes to generate a downward traveling wavelet having increased high frequency content and reduced content at a peak frequency determined by initial testing.

Neural Computations Mediating One-Shot Learning in the Human Brain

Science.gov (United States)

Lee, Sang Wan; O’Doherty, John P.; Shimojo, Shinsuke

2015-01-01

Incremental learning, in which new knowledge is acquired gradually through trial and error, can be distinguished from one-shot learning, in which the brain learns rapidly from only a single pairing of a stimulus and a consequence. Very little is known about how the brain transitions between these two fundamentally different forms of learning. Here we test a computational hypothesis that uncertainty about the causal relationship between a stimulus and an outcome induces rapid changes in the rate of learning, which in turn mediates the transition between incremental and one-shot learning. By using a novel behavioral task in combination with functional magnetic resonance imaging (fMRI) data from human volunteers, we found evidence implicating the ventrolateral prefrontal cortex and hippocampus in this process. The hippocampus was selectively “switched” on when one-shot learning was predicted to occur, while the ventrolateral prefrontal cortex was found to encode uncertainty about the causal association, exhibiting increased coupling with the hippocampus for high-learning rates, suggesting this region may act as a “switch,” turning on and off one-shot learning as required. PMID:25919291

78 FR 65573 - Migratory Bird Hunting; Application for Approval of Copper-Clad Iron Shot and Fluoropolymer Shot...

Science.gov (United States)

2013-11-01

... shot, causing sediment/soil and water contamination and the direct ingestion of shot by aquatic and.... Shot[supreg]. * Coatings of copper, nickel, tin, zinc, zinc chloride, zinc chrome, and fluoropolymers...

The Problem of Shot Selection in Basketball

Science.gov (United States)

Skinner, Brian

2012-01-01

In basketball, every time the offense produces a shot opportunity the player with the ball must decide whether the shot is worth taking. In this article, I explore the question of when a team should shoot and when they should pass up the shot by considering a simple theoretical model of the shot selection process, in which the quality of shot opportunities generated by the offense is assumed to fall randomly within a uniform distribution. Within this model I derive an answer to the question “how likely must the shot be to go in before the player should take it?” and I show that this lower cutoff for shot quality depends crucially on the number of shot opportunities remaining (say, before the shot clock expires), with larger demanding that only higher-quality shots should be taken. The function is also derived in the presence of a finite turnover rate and used to predict the shooting rate of an optimal-shooting team as a function of time. The theoretical prediction for the optimal shooting rate is compared to data from the National Basketball Association (NBA). The comparison highlights some limitations of the theoretical model, while also suggesting that NBA teams may be overly reluctant to shoot the ball early in the shot clock. PMID:22295109

The problem of shot selection in basketball.

Directory of Open Access Journals (Sweden)

Brian Skinner

Full Text Available In basketball, every time the offense produces a shot opportunity the player with the ball must decide whether the shot is worth taking. In this article, I explore the question of when a team should shoot and when they should pass up the shot by considering a simple theoretical model of the shot selection process, in which the quality of shot opportunities generated by the offense is assumed to fall randomly within a uniform distribution. Within this model I derive an answer to the question "how likely must the shot be to go in before the player should take it?" and I show that this lower cutoff for shot quality f depends crucially on the number n of shot opportunities remaining (say, before the shot clock expires, with larger n demanding that only higher-quality shots should be taken. The function f(n is also derived in the presence of a finite turnover rate and used to predict the shooting rate of an optimal-shooting team as a function of time. The theoretical prediction for the optimal shooting rate is compared to data from the National Basketball Association (NBA. The comparison highlights some limitations of the theoretical model, while also suggesting that NBA teams may be overly reluctant to shoot the ball early in the shot clock.

The problem of shot selection in basketball.

Science.gov (United States)

Skinner, Brian

2012-01-01

In basketball, every time the offense produces a shot opportunity the player with the ball must decide whether the shot is worth taking. In this article, I explore the question of when a team should shoot and when they should pass up the shot by considering a simple theoretical model of the shot selection process, in which the quality of shot opportunities generated by the offense is assumed to fall randomly within a uniform distribution. Within this model I derive an answer to the question "how likely must the shot be to go in before the player should take it?" and I show that this lower cutoff for shot quality f depends crucially on the number n of shot opportunities remaining (say, before the shot clock expires), with larger n demanding that only higher-quality shots should be taken. The function f(n) is also derived in the presence of a finite turnover rate and used to predict the shooting rate of an optimal-shooting team as a function of time. The theoretical prediction for the optimal shooting rate is compared to data from the National Basketball Association (NBA). The comparison highlights some limitations of the theoretical model, while also suggesting that NBA teams may be overly reluctant to shoot the ball early in the shot clock.

Efficacy of triplet regimen antiemetic therapy for chemotherapy-induced nausea and vomiting (CINV) in bone and soft tissue sarcoma patients receiving highly emetogenic chemotherapy, and an efficacy comparison of single-shot palonosetron and consecutive-day granisetron for CINV in a randomized, single-blinded crossover study

International Nuclear Information System (INIS)

Kimura, Hiroaki; Yamamoto, Norio; Shirai, Toshiharu; Nishida, Hideji; Hayashi, Katsuhiro; Tanzawa, Yoshikazu; Takeuchi, Akihiko; Igarashi, Kentaro; Inatani, Hiroyuki; Shimozaki, Shingo; Kato, Takashi; Aoki, Yu; Higuchi, Takashi; Tsuchiya, Hiroyuki

2015-01-01

The first aim of this study was to evaluate combination antiemetic therapy consisting of 5-HT 3 receptor antagonists, neurokinin-1 receptor antagonists (NK-1RAs), and dexamethasone for multiple high emetogenic risk (HER) anticancer agents in bone and soft tissue sarcoma. The second aim was to compare the effectiveness of single-shot palonosetron and consecutive-day granisetron in a randomized, single-blinded crossover study. A single randomization method was used to assign eligible patients to the palonosetron or granisetron arm. Patients in the palonosetron arm received a palonosetron regimen during the first and third chemotherapy courses and a granisetron regimen during the second and fourth courses. All patients received NK-1RA and dexamethasone. Patients receiving the palonosetron regimen were administered 0.75 mg palonosetron on day 1, and patients receiving the granisetron regimen were administered 3 mg granisetron twice daily on days 1 through 5. All 24 patients in this study received at least 4 chemotherapy courses. A total of 96 courses of antiemetic therapy were evaluated. Overall, the complete response CR rate (no emetic episodes and no rescue medication use) was 34%, while the total control rate (a CR plus no nausea) was 7%. No significant differences were observed between single-shot palonosetron and consecutive-day granisetron. Antiemetic therapy with a 3-drug combination was not sufficient to control chemotherapy-induced nausea and vomiting (CINV) during chemotherapy with multiple HER agents for bone and soft tissue sarcoma. This study also demonstrated that consecutive-day granisetron was not inferior to single-shot palonosetron for treating CINV

Shot-noise dominant regime of a nanoparticle in a laser beam

Science.gov (United States)

Zhong, Changchun; Robicheaux, Francis

2017-04-01

The technique of laser levitation of nanoparticles has become increasingly promising in the study of cooling and controlling mesoscopic quantum systems. Unlike a mechanical system, the levitated nanoparticle is less exposed to thermalization and decoherence due to the absence of direct contact with a thermal environment. In ultrahigh vacuum, the dominant source of decoherence comes from the unavoidable photon recoil from the optical trap which sets an ultimate bound for the control of levitated systems. In this paper, we study the shot noise heating and the parametric feedback cooling of an optically trapped anisotropic nanoparticle in the laser shot noise dominant regime. The rotational trapping frequency and shot noise heating rate have a dependence on the shape of the trapped particle. For an ellipsoidal particle, the ratio of the axis lengths and the overall size controls the shot noise heating rate relative to the rotational frequency. For a near spherical nanoparticle, the effective heating rate for the rotational degrees of freedom is smaller than that for translation suggesting that the librational ground state may be easier to achieve than the vibrational ground state.

Single-shot quantum nondemolition measurement of a quantum-dot electron spin using cavity exciton-polaritons

Science.gov (United States)

Puri, Shruti; McMahon, Peter L.; Yamamoto, Yoshihisa

2014-10-01

We propose a scheme to perform single-shot quantum nondemolition (QND) readout of the spin of an electron trapped in a semiconductor quantum dot (QD). Our proposal relies on the interaction of the QD electron spin with optically excited, quantum well (QW) microcavity exciton-polaritons. The spin-dependent Coulomb exchange interaction between the QD electron and cavity polaritons causes the phase and intensity response of left circularly polarized light to be different than that of right circularly polarized light, in such a way that the QD electron's spin can be inferred from the response to a linearly polarized probe reflected or transmitted from the cavity. We show that with careful device design it is possible to essentially eliminate spin-flip Raman transitions. Thus a QND measurement of the QD electron spin can be performed within a few tens of nanoseconds with fidelity ˜99.95%. This improves upon current optical QD spin readout techniques across multiple metrics, including speed and scalability.

Comparison of Multi-shot Models for Short-term Re-identification of People using RGB-D Sensors

DEFF Research Database (Denmark)

Møgelmose, Andreas; Bahnsen, Chris; Moeslund, Thomas B.

2015-01-01

This work explores different types of multi-shot descriptors for re-identification in an on-the-fly enrolled environment using RGB-D sensors. We present a full re-identification pipeline complete with detection, segmentation, feature extraction, and re-identification, which expands on previous work...... by using multi-shot descriptors modeling people over a full camera pass instead of single frames with no temporal linking. We compare two different multi-shot models; mean histogram and histogram series, and test them each in 3 different color spaces. Both histogram descriptors are assisted by a depth...

Assessing Model Characterization of Single Source ...

Science.gov (United States)

Aircraft measurements made downwind from specific coal fired power plants during the 2013 Southeast Nexus field campaign provide a unique opportunity to evaluate single source photochemical model predictions of both O3 and secondary PM2.5 species. The model did well at predicting downwind plume placement. The model shows similar patterns of an increasing fraction of PM2.5 sulfate ion to the sum of SO2 and PM2.5 sulfate ion by distance from the source compared with ambient based estimates. The model was less consistent in capturing downwind ambient based trends in conversion of NOX to NOY from these sources. Source sensitivity approaches capture near-source O3 titration by fresh NO emissions, in particular subgrid plume treatment. However, capturing this near-source chemical feature did not translate into better downwind peak estimates of single source O3 impacts. The model estimated O3 production from these sources but often was lower than ambient based source production. The downwind transect ambient measurements, in particular secondary PM2.5 and O3, have some level of contribution from other sources which makes direct comparison with model source contribution challenging. Model source attribution results suggest contribution to secondary pollutants from multiple sources even where primary pollutants indicate the presence of a single source. The National Exposure Research Laboratory (NERL) Computational Exposure Division (CED) develops and evaluates data, deci

Shot noise and electronic properties in the inversion-symmetric Weyl semimetal resonant structure

Science.gov (United States)

Yang, Yanling; Bai, Chunxu; Xu, Xiaoguang; Jiang, Yong

2018-02-01

Using the transfer matrix method, the authors combine the analytical formula with numerical calculation to explore the shot noise and conductance of massless Weyl fermions in the Weyl semimetal resonant junction. By varying the barrier strength, the structure of the junction, the Fermi energy, and the crystallographic angle, the shot noise and conductance can be tuned efficiently. For a quasiperiodic superlattice, in complete contrast to the conventional junction case, the effect of the disorder strength on the shot noise and conductance depends on the competition of classical tunneling and Klein tunneling. Moreover, the delta barrier structure is also vital in determining the shot noise and conductance. In particular, a universal Fano factor has been found in a single delta potential case, whereas the resonant structure of the Fano factor perfectly matches with the number of barriers in a delta potential superlattice. These results are crucial for engineering nanoelectronic devices based on this topological semimetal material.

A Shot Number Based Approach to Performance Analysis in Table Tennis

Directory of Open Access Journals (Sweden)

Tamaki Sho

2017-01-01

Full Text Available The current study proposes a novel approach that improves the conventional performance analysis in table tennis by introducing the concept of frequency, or the number of shots, of each shot number. The improvements over the conventional method are as follows: better accuracy of the evaluation of skills and tactics of players, additional insights into scoring and returning skills and ease of understanding the results with a single criterion. The performance analysis of matches played at the 2012 Summer Olympics in London was conducted using the proposed method. The results showed some effects of the shot number and gender differences in table tennis. Furthermore, comparisons were made between Chinese players and players from other countries, what threw light on the skills and tactics of the Chinese players. The present findings demonstrate that the proposed method provides useful information and has some advantages over the conventional method.

Feasibility of one-shot-per-crystal structure determination using Laue diffraction

Energy Technology Data Exchange (ETDEWEB)

Cornaby, Sterling [School of Applied and Engineering Physics, Cornell University, Ithaca, New York (United States); CHESS (Cornell High Energy Synchrotron Source), Cornell University, Ithaca, New York (United States); Szebenyi, Doletha M. E. [MacCHESS (Macromolecular Diffraction Facilities at CHESS), Cornell University, Ithaca, New York (United States); Smilgies, Detlef-M. [CHESS (Cornell High Energy Synchrotron Source), Cornell University, Ithaca, New York (United States); Schuller, David J.; Gillilan, Richard; Hao, Quan [MacCHESS (Macromolecular Diffraction Facilities at CHESS), Cornell University, Ithaca, New York (United States); Bilderback, Donald H., E-mail: dhb2@cornell.edu [School of Applied and Engineering Physics, Cornell University, Ithaca, New York (United States); CHESS (Cornell High Energy Synchrotron Source), Cornell University, Ithaca, New York (United States)

2010-01-01

Structure determination was successfully carried out using single Laue exposures from a group of lysozyme crystals. The Laue method may be a viable option for collection of one-shot-per-crystal data from microcrystals. Crystal size is an important factor in determining the number of diffraction patterns which may be obtained from a protein crystal before severe radiation damage sets in. As crystal dimensions decrease this number is reduced, eventually falling to one, at which point a complete data set must be assembled using data from multiple crystals. When only a single exposure is to be collected from each crystal, the polychromatic Laue technique may be preferable to monochromatic methods owing to its simultaneous recording of a large number of fully recorded reflections per image. To assess the feasibility of solving structures using single Laue images from multiple crystals, data were collected using a ‘pink’ beam at the CHESS D1 station from groups of lysozyme crystals with dimensions of the order of 20–30 µm mounted on MicroMesh grids. Single-shot Laue data were used for structure determination by molecular replacement and correct solutions were obtained even when as few as five crystals were used.

Feasibility of one-shot-per-crystal structure determination using Laue diffraction

International Nuclear Information System (INIS)

Cornaby, Sterling; Szebenyi, Doletha M. E.; Smilgies, Detlef-M.; Schuller, David J.; Gillilan, Richard; Hao, Quan; Bilderback, Donald H.

2010-01-01

Structure determination was successfully carried out using single Laue exposures from a group of lysozyme crystals. The Laue method may be a viable option for collection of one-shot-per-crystal data from microcrystals. Crystal size is an important factor in determining the number of diffraction patterns which may be obtained from a protein crystal before severe radiation damage sets in. As crystal dimensions decrease this number is reduced, eventually falling to one, at which point a complete data set must be assembled using data from multiple crystals. When only a single exposure is to be collected from each crystal, the polychromatic Laue technique may be preferable to monochromatic methods owing to its simultaneous recording of a large number of fully recorded reflections per image. To assess the feasibility of solving structures using single Laue images from multiple crystals, data were collected using a ‘pink’ beam at the CHESS D1 station from groups of lysozyme crystals with dimensions of the order of 20–30 µm mounted on MicroMesh grids. Single-shot Laue data were used for structure determination by molecular replacement and correct solutions were obtained even when as few as five crystals were used

Shot peening: theory applications and recent development

International Nuclear Information System (INIS)

Zaid, A.I.O.

1999-01-01

Shot peening is a surface treatment process by which the surface of an elastic-plastic target material is subjected to multiple impact by spherical shots made of glass or hard steel in a defined and controlled manner. The multiple impact produces a dynamic compressive stress at the surface of the target, thereby effectively improving its mechanical behavior and eliminates cracks and imperfections hence improving the fatigue life and strength. In this paper, the theory and practice of the shot peening process are reviewed. The main parameters involved in the process and their effects on shot peening are presented and discussed which include: shot material, size and geometry, shot pressure and shot velocity, projection angle, exposure time, table rotational speed, standoff distance coverage, saturation and peening intensity. Furthermore, the effect of shot peening on fatigue life and fatigue strength of ferrous and non-ferrous materials together with other different industrial applications of the process are given. Recent developments in utilizing the shot peening process with welded parts and hard chromium plating aiming at improvement of their fatigue strength and their resistance to stress corrosion cracking are also presented and discussed. Finally, future development of the process are outlined and discussed. (author)

Assembly procedure for Shot Loading Platform

International Nuclear Information System (INIS)

Routh, R.D.

1995-01-01

This supporting document describes the assembly procedure for the Shot Loading Platform. The Shot Loading Platform is used by multiple equipment removal projects to load shielding shot in the annular spaces of the equipment storage containers. The platform height is adjustable to accommodate different sizes of storage containers and transport assemblies

Data Release Report for Source Physics Experiments 2 and 3 (SPE-2 and SPE-3) Nevada National Security Site

Energy Technology Data Exchange (ETDEWEB)

Townsend, Margaret [National Security Technologies, LLC, Las Vegas, NV (United States). Nevada Test Site; Obi, Curtis [National Security Technologies, LLC, Las Vegas, NV (United States). Nevada Test Site

2015-01-26

The second Source Physics Experiment shot (SPE-2) was conducted in Nevada on October 25, 2011, at 1900:00.011623 Greenwich Mean Time (GMT). The explosive source was 997 kilograms (kg) trinitrotoluene (TNT) equivalent of sensitized heavy ammonium fuel oil (SHANFO) detonated at a depth of 45.7 meters (m). The third Source Physics Experiment shot (SPE-3) was conducted in Nevada on July 24, 2012, at 1800:00.44835 GMT. The explosive source was 905 kg TNT equivalent of SHANFO detonated at a depth of 45.8 m. Both shots were recorded by an extensive set of instrumentation that includes sensors both at near-field (less than 100 m) and far-field (100 m or greater) distances. The near-field instruments consisted of three-component accelerometers deployed in boreholes at 15, 46, and 55 m depths around the shot and a set of single-component vertical accelerometers on the surface. The far-field network was composed of a variety of seismic and acoustic sensors, including short-period geophones, broadband seismometers, three-component accelerometers, and rotational seismometers at distances of 100 m to 25 kilometers. This report coincides with the release of these data for analysts and organizations that are not participants in this program. This report describes the second and third Source Physics Experiment shots and the various types of near-field and far-field data that are available.

Tailoring single-photon and multiphoton probabilities of a single-photon on-demand source

International Nuclear Information System (INIS)

Migdall, A.L.; Branning, D.; Castelletto, S.

2002-01-01

As typically implemented, single-photon sources cannot be made to produce single photons with high probability, while simultaneously suppressing the probability of yielding two or more photons. Because of this, single-photon sources cannot really produce single photons on demand. We describe a multiplexed system that allows the probabilities of producing one and more photons to be adjusted independently, enabling a much better approximation of a source of single photons on demand

Efficacy of triplet regimen antiemetic therapy for chemotherapy-induced nausea and vomiting (CINV) in bone and soft tissue sarcoma patients receiving highly emetogenic chemotherapy, and an efficacy comparison of single-shot palonosetron and consecutive-day granisetron for CINV in a randomized, single-blinded crossover study.

Science.gov (United States)

Kimura, Hiroaki; Yamamoto, Norio; Shirai, Toshiharu; Nishida, Hideji; Hayashi, Katsuhiro; Tanzawa, Yoshikazu; Takeuchi, Akihiko; Igarashi, Kentaro; Inatani, Hiroyuki; Shimozaki, Shingo; Kato, Takashi; Aoki, Yu; Higuchi, Takashi; Tsuchiya, Hiroyuki

2015-03-01

The first aim of this study was to evaluate combination antiemetic therapy consisting of 5-HT3 receptor antagonists, neurokinin-1 receptor antagonists (NK-1RAs), and dexamethasone for multiple high emetogenic risk (HER) anticancer agents in bone and soft tissue sarcoma. The second aim was to compare the effectiveness of single-shot palonosetron and consecutive-day granisetron in a randomized, single-blinded crossover study. A single randomization method was used to assign eligible patients to the palonosetron or granisetron arm. Patients in the palonosetron arm received a palonosetron regimen during the first and third chemotherapy courses and a granisetron regimen during the second and fourth courses. All patients received NK-1RA and dexamethasone. Patients receiving the palonosetron regimen were administered 0.75 mg palonosetron on day 1, and patients receiving the granisetron regimen were administered 3 mg granisetron twice daily on days 1 through 5. All 24 patients in this study received at least 4 chemotherapy courses. A total of 96 courses of antiemetic therapy were evaluated. Overall, the complete response CR rate (no emetic episodes and no rescue medication use) was 34%, while the total control rate (a CR plus no nausea) was 7%. No significant differences were observed between single-shot palonosetron and consecutive-day granisetron. Antiemetic therapy with a 3-drug combination was not sufficient to control chemotherapy-induced nausea and vomiting (CINV) during chemotherapy with multiple HER agents for bone and soft tissue sarcoma. This study also demonstrated that consecutive-day granisetron was not inferior to single-shot palonosetron for treating CINV. © 2014 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.

Development of Compton X-ray spectrometer for high energy resolution single-shot high-flux hard X-ray spectroscopy

Energy Technology Data Exchange (ETDEWEB)

Kojima, Sadaoki, E-mail: kojima-s@ile.osaka-u.ac.jp, E-mail: sfujioka@ile.osaka-u.ac.jp; Ikenouchi, Takahito; Arikawa, Yasunobu; Sakata, Shohei; Zhang, Zhe; Abe, Yuki; Nakai, Mitsuo; Nishimura, Hiroaki; Shiraga, Hiroyuki; Fujioka, Shinsuke, E-mail: kojima-s@ile.osaka-u.ac.jp, E-mail: sfujioka@ile.osaka-u.ac.jp; Azechi, Hiroshi [Institute of Laser Engineering, Osaka University, 2-6 Yamada-oka, Suita, Osaka 565-0871 (Japan); Ozaki, Tetsuo [National Institute for Fusion Science, 322-6 Oroshi, Toki, Gifu 509-5292 (Japan); Miyamoto, Shuji; Yamaguchi, Masashi; Takemoto, Akinori [Laboratory of Advanced Science and Technology for Industry, University of Hyogo, 3-1-2 Kouto, Kamigori-cho, Ako-gun, Hyogo 678-1205 (Japan)

2016-04-15

Hard X-ray spectroscopy is an essential diagnostics used to understand physical processes that take place in high energy density plasmas produced by intense laser-plasma interactions. A bundle of hard X-ray detectors, of which the responses have different energy thresholds, is used as a conventional single-shot spectrometer for high-flux (>10{sup 13} photons/shot) hard X-rays. However, high energy resolution (Δhv/hv < 0.1) is not achievable with a differential energy threshold (DET) X-ray spectrometer because its energy resolution is limited by energy differences between the response thresholds. Experimental demonstration of a Compton X-ray spectrometer has already been performed for obtaining higher energy resolution than that of DET spectrometers. In this paper, we describe design details of the Compton X-ray spectrometer, especially dependence of energy resolution and absolute response on photon-electron converter design and its background reduction scheme, and also its application to the laser-plasma interaction experiment. The developed spectrometer was used for spectroscopy of bremsstrahlung X-rays generated by intense laser-plasma interactions using a 200 μm thickness SiO{sub 2} converter. The X-ray spectrum obtained with the Compton X-ray spectrometer is consistent with that obtained with a DET X-ray spectrometer, furthermore higher certainly of a spectral intensity is obtained with the Compton X-ray spectrometer than that with the DET X-ray spectrometer in the photon energy range above 5 MeV.

Short wavelength limits of current shot noise suppression

International Nuclear Information System (INIS)

Nause, Ariel; Dyunin, Egor; Gover, Avraham

2014-01-01

Shot noise in electron beam was assumed to be one of the features beyond control of accelerator physics. Current results attained in experiments at Accelerator Test Facility in Brookhaven and Linac Coherent Light Source in Stanford suggest that the control of the shot noise in electron beam (and therefore of spontaneous radiation and Self Amplified Spontaneous Emission of Free Electron Lasers) is feasible at least in the visible range of the spectrum. Here, we present a general linear formulation for collective micro-dynamics of e-beam noise and its control. Specifically, we compare two schemes for current noise suppression: a quarter plasma wavelength drift section and a combined drift/dispersive (transverse magnetic field) section. We examine and compare their limits of applicability at short wavelengths via considerations of electron phase-spread and the related Landau damping effect

Short wavelength limits of current shot noise suppression

Energy Technology Data Exchange (ETDEWEB)

Nause, Ariel, E-mail: arielnau@post.tau.ac.il [Faculty of Exact Sciences, Department of Physics, Tel Aviv University, Tel Aviv (Israel); Dyunin, Egor; Gover, Avraham [Faculty of Engineering, Department of Physical Electronics, Tel Aviv University, Tel Aviv (Israel)

2014-08-15

Shot noise in electron beam was assumed to be one of the features beyond control of accelerator physics. Current results attained in experiments at Accelerator Test Facility in Brookhaven and Linac Coherent Light Source in Stanford suggest that the control of the shot noise in electron beam (and therefore of spontaneous radiation and Self Amplified Spontaneous Emission of Free Electron Lasers) is feasible at least in the visible range of the spectrum. Here, we present a general linear formulation for collective micro-dynamics of e-beam noise and its control. Specifically, we compare two schemes for current noise suppression: a quarter plasma wavelength drift section and a combined drift/dispersive (transverse magnetic field) section. We examine and compare their limits of applicability at short wavelengths via considerations of electron phase-spread and the related Landau damping effect.

Data Release Report for Source Physics Experiments 2 and 3 (SPE-2 and SPE-3) Nevada National Security Site

Energy Technology Data Exchange (ETDEWEB)

Townsend, Margaret [National Security Technologies, LLC. (NSTec), Las Vegas, NV (United States); Obi, Curtis [National Security Technologies, LLC. (NSTec), Las Vegas, NV (United States)

2015-04-30

The second Source Physics Experiment shot (SPE-2) was conducted in Nevada on October 25, 2011, at 1900:00.011623 Greenwich Mean Time (GMT). The explosive source was 997 kilograms (kg) trinitrotoluene (TNT) equivalent of sensitized heavy ammonium fuel oil (SHANFO) detonated at a depth of 45.7 meters (m). The third Source Physics Experiment shot (SPE-3) was conducted in Nevada on July 24, 2012, at 1800:00.44835 GMT. The explosive source was 905 kg TNT equivalent of SHANFO detonated at a depth of 45.8 m. Both shots were recorded by an extensive set of instrumentation that includes sensors both at near-field (less than 100 m) and far-field (100 m or greater) distances. The near-field instruments consisted of three-component accelerometers deployed in boreholes at 15, 46, and 55 m depths around the shot and a set of single-component vertical accelerometers on the surface. The far-field network was composed of a variety of seismic and acoustic sensors, including short-period geophones, broadband seismometers, three-component accelerometers, and rotational seismometers at distances of 100 m to 25 kilometers. This report coincides with the release of these data for analysts and organizations that are not participants in this program. This report describes the second and third Source Physics Experiment shots and the various types of near-field and farfield data that are available.This revised document includes reports on baseline shift corrections for the SPE-2 and SPE-3 shots that were missing from the original January 2015 version.

Cavity Exciton-Polariton mediated, Single-Shot Quantum Non-Demolition measurement of a Quantum Dot Electron Spin

Science.gov (United States)

Puri, Shruti; McMahon, Peter; Yamamoto, Yoshihisa

2014-03-01

The quantum non-demolition (QND) measurement of a single electron spin is of great importance in measurement-based quantum computing schemes. The current single-shot readout demonstrations exhibit substantial spin-flip backaction. We propose a QND readout scheme for quantum dot (QD) electron spins in Faraday geometry, which differs from previous proposals and implementations in that it relies on a novel physical mechanism: the spin-dependent Coulomb exchange interaction between a QD spin and optically-excited quantum well (QW) microcavity exciton-polaritons. The Coulomb exchange interaction causes a spin-dependent shift in the resonance energy of the polarized polaritons, thus causing the phase and intensity response of left circularly polarized light to be different to that of the right circularly polarized light. As a result the QD electron's spin can be inferred from the response to a linearly polarized probe. We show that by a careful design of the system, any spin-flip backaction can be eliminated and a QND measurement of the QD electron spin can be performed within a few 10's of nanoseconds with fidelity 99:95%. This improves upon current optical QD spin readout techniques across multiple metrics, including fidelity, speed and scalability. National Institute of Informatics, 2-1-2 Hitotsubashi, Chiyoda-ku, Tokyo 101-8430, Japan.

ON THE USE OF SHOT NOISE FOR PHOTON COUNTING

Energy Technology Data Exchange (ETDEWEB)

Zmuidzinas, Jonas, E-mail: jonas@caltech.edu [Division of Physics, Mathematics, and Astronomy, California Institute Institute of Technology, Pasadena, CA 91125 (United States)

2015-11-01

Lieu et al. have recently claimed that it is possible to substantially improve the sensitivity of radio-astronomical observations. In essence, their proposal is to make use of the intensity of the photon shot noise as a measure of the photon arrival rate. Lieu et al. provide a detailed quantum-mechanical calculation of a proposed measurement scheme that uses two detectors and conclude that this scheme avoids the sensitivity degradation that is associated with photon bunching. If correct, this result could have a profound impact on radio astronomy. Here I present a detailed analysis of the sensitivity attainable using shot-noise measurement schemes that use either one or two detectors, and demonstrate that neither scheme can avoid the photon bunching penalty. I perform both semiclassical and fully quantum calculations of the sensitivity, obtaining consistent results, and provide a formal proof of the equivalence of these two approaches. These direct calculations are furthermore shown to be consistent with an indirect argument based on a correlation method that establishes an independent limit to the sensitivity of shot-noise measurement schemes. Furthermore, these calculations are directly applicable to the regime of interest identified by Lieu et al. Collectively, these results conclusively demonstrate that the photon-bunching sensitivity penalty applies to shot-noise measurement schemes just as it does to ordinary photon counting, in contradiction to the fundamental claim made by Lieu et al. The source of this contradiction is traced to a logical fallacy in their argument.

Generalised shot noise Cox processes

DEFF Research Database (Denmark)

Møller, Jesper; Torrisi, Giovanni Luca

We introduce a new class of Cox cluster processes called generalised shot-noise processes (GSNCPs), which extends the definition of shot noise Cox processes (SNCPs) in two directions: the point process which drives the shot noise is not necessarily Poisson, and the kernel of the shot noise can...... be random. Thereby a very large class of models for aggregated or clustered point patterns is obtained. Due to the structure of GSNCPs, a number of useful results can be established. We focus first on deriving summary statistics for GSNCPs and next on how to make simulation for GSNCPs. Particularly, results...... for first and second order moment measures, reduced Palm distributions, the -function, simulation with or without edge effects, and conditional simulation of the intensity function driving a GSNCP are given. Our results are exemplified for special important cases of GSNCPs, and we discuss the relation...

Portable light-emitting diode-based photometer with one-shot optochemical sensors for measurement in the field.

Science.gov (United States)

Palma, A J; Ortigosa, J M; Lapresta-Fernández, A; Fernández-Ramos, M D; Carvajal, M A; Capitán-Vallvey, L F

2008-10-01

This report describes the electronics of a portable, low-cost, light-emitting diode (LED)-based photometer dedicated to one-shot optochemical sensors. Optical detection is made through a monolithic photodiode with an on-chip single-supply transimpedance amplifier that reduces some drawbacks such as leakage currents, interferences, and parasitic capacitances. The main instrument characteristics are its high light source stability and thermal correction. The former is obtained by means of the optical feedback from the LED polarization circuit, implementing a pseudo-two light beam scheme from a unique light source with a built-in beam splitter. The feedback loop has also been used to adjust the LED power in several ranges. Moreover, the low-thermal coefficient achieved (-90 ppm/degrees C) is compensated by thermal monitoring and calibration function compensation in the digital processing. The hand-held instrument directly gives the absorbance ratio used as the analytical parameter and the analyte concentration after programming the calibration function in the microcontroller. The application of this photometer for the determination of potassium and nitrate, using one-shot sensors with ionophore-based chemistries is also demonstrated, with a simple analytical methodology that shortens the analysis time, eliminating some calibrating solutions (HCl, NaOH, and buffer). Therefore, this compact instrument is suitable for real-time analyte determination and operation in the field.

Unconditional violation of the shot-noise limit in photonic quantum metrology

Science.gov (United States)

Slussarenko, Sergei; Weston, Morgan M.; Chrzanowski, Helen M.; Shalm, Lynden K.; Verma, Varun B.; Nam, Sae Woo; Pryde, Geoff J.

2017-11-01

Interferometric phase measurement is widely used to precisely determine quantities such as length, speed and material properties1-3. Without quantum correlations, the best phase sensitivity Δ ϕ achievable using n photons is the shot-noise limit, Δ ϕ =1 /√{n }. Quantum-enhanced metrology promises better sensitivity, but, despite theoretical proposals stretching back decades3,4, no measurement using photonic (that is, definite photon number) quantum states has truly surpassed the shot-noise limit. Instead, all such demonstrations, by discounting photon loss, detector inefficiency or other imperfections, have considered only a subset of the photons used. Here, we use an ultrahigh-efficiency photon source and detectors to perform unconditional entanglement-enhanced photonic interferometry. Sampling a birefringent phase shift, we demonstrate precision beyond the shot-noise limit without artificially correcting our results for loss and imperfections. Our results enable quantum-enhanced phase measurements at low photon flux and open the door to the next generation of optical quantum metrology advances.

Single shot “3-in-1” femoral nerve blockade with 0.25% or 0.375% levobupivacaine provides similar postoperative analgesia for total knee replacement

OpenAIRE

APAN, Alpaslan; SARI, Filiz; EKMEKÇİ, Alp Burak

2010-01-01

To compare postoperative analgesia provided by single shot "3-in-1" femoral nerve blockade using 0.25% or 0.375% levobupivacaine in preceding with spinal anesthesia for unilateral total knee replacement surgery. Materials and methods: Forty consenting patients undergoing unilateral total knee arthroplasty were included in this prospective randomized study. Spinal anesthesia was achieved with 15 mg plain bupivacaine at the L3-4 or L4-5 interspace. After resolution of the sp...

Orchestrating Shots for the National Ignition Facility (NIF)

International Nuclear Information System (INIS)

Mathisen, D G; Bettenhausen, R C; Beeler, R G; Bowers, G A; Carey, R W; Casavant, D D; Cline, B D; Demaret, R D; Domyancic, D M; Elko, S D; Fisher, J M; Krammen, J E; Lagin, L J; Ludwigsen, A P; Patterson, R W; Sanchez, R J; Stout, E A

2005-01-01

The National Ignition Facility (NIF), currently under construction at the Lawrence Livermore National Laboratory, is a stadium-sized facility containing a 192-beam, 1.8 Megajoule, 500-Terawatt, ultra-violet laser system together with a 10-meter diameter target chamber with room for nearly 100 experimental diagnostics. When completed, NIF will be the world's largest and most energetic laser experimental system, providing an international center to study inertial confinement fusion and physics of matter at extreme densities and pressures. The NIF is operated by the Integrated Computer Control System (ICCS), which is a layered architecture of over 700 lower-level front-end processors attached to nearly 60,000 control points and coordinated by higher-level supervisory subsystems in the main control room. A shot automation framework has been developed and deployed during the past year to orchestrate and automate shots performed at the NIF using the ICCS. The Shot Automation framework is designed to automate 4-8 hour shot sequences, that includes deriving shot goals from an experiment definition, set up of the laser and diagnostics, automatic alignment of laser beams, and a countdown to charge and fire the lasers. These sequences consist of set of preparatory verification shots, leading to amplified system shots followed by post-shot analysis and archiving. The framework provides for a flexible, model-based work-flow execution, driven by scripted automation called macro steps. The shot director software is the orchestrating component of a very flexible automation layer which allows us to define, coordinate and reuse simpler automation sequences. This software provides a restricted set of shot life cycle state transitions to 26 collaboration supervisors that automate 8-laser beams (bundle) and a common set of shared resources. Each collaboration supervisor commands approximately 10 subsystem shot supervisors that perform automated control and status verification

Anatomical details of the brainstem and cranial nerves visualized by high resolution readout-segmented multi-shot echo-planar diffusion-weighted images using unidirectional MPG at 3T

International Nuclear Information System (INIS)

Naganawa, Shinji; Yamazaki, Masahiro; Kawai, Hisashi; Sone, Michihiko; Nakashima, Tsutomu; Isoda, Haruo

2011-01-01

We compared diffusion-weighted imaging (DWI) with readout-segmented multi-shot echo-planar imaging (rs-EPI) and single-shot EPI, both using unidirectional motion-probing gradient, in 10 patients for visualization of the anatomical structures in the brainstem. DWI by rs-EPI was significantly better than DWI by single-shot EPI for visualizing the medial longitudinal fasciculus, lateral lemniscus, corticospinal tract, and seventh/eighth cranial nerves and offered significantly less distortion of the brainstem. (author)

Anterior chamber configuration in patients with glaucoma: MR gonioscopy evaluation with half-Fourier single-shot RARE sequence and microscopy coil.

Science.gov (United States)

Tanitame, Keizo; Sasaki, Ko; Sone, Takashi; Uyama, Shinji; Sumida, Masumi; Ichiki, Toshio; Ito, Katsuhide

2008-10-01

The purpose of the study was to determine the accuracy of half-Fourier single-shot rapid acquisition with relaxation enhancement high-spatial-resolution magnetic resonance (MR) imaging performed with a microscopy coil in the diagnosis of narrow anterior chamber angle in patients with glaucoma. Slit-lamp biomicroscopy served as the reference standard. The institutional review board approved this study, and written informed consent was obtained from the 20 recruited patients. There was excellent agreement between MR gonioscopy and slit-lamp biomicroscopy in the classification of anterior chamber angles as narrow or open (kappa = 0.89 [95% confidence interval: 0.69, 1.10]). MR gonioscopy has substantial potential as a technique used to evaluate glaucoma. (c) RSNA, 2008.

Land Streamer Surveying Using Multiple Sources

KAUST Repository

Mahmoud, Sherif; Schuster, Gerard T.

2014-01-01

are fired. In another example, a system includes a land streamer including a plurality of receivers, a first shot source located adjacent to the proximal end of the land streamer, and a second shot source located in-line with the land streamer and the first

Catastrophe Insurance Modeled by Shot-Noise Processes

Directory of Open Access Journals (Sweden)

Thorsten Schmidt

2014-02-01

Full Text Available Shot-noise processes generalize compound Poisson processes in the following way: a jump (the shot is followed by a decline (noise. This constitutes a useful model for insurance claims in many circumstances; claims due to natural disasters or self-exciting processes exhibit similar features. We give a general account of shot-noise processes with time-inhomogeneous drivers inspired by recent results in credit risk. Moreover, we derive a number of useful results for modeling and pricing with shot-noise processes. Besides this, we obtain some highly tractable examples and constitute a useful modeling tool for dynamic claims processes. The results can in particular be used for pricing Catastrophe Bonds (CAT bonds, a traded risk-linked security. Additionally, current results regarding the estimation of shot-noise processes are reviewed.

A review on the basketball jump shot.

Science.gov (United States)

Okazaki, Victor H A; Rodacki, André L F; Satern, Miriam N

2015-06-01

The ability to shoot an effective jump shot in the sport of basketball is critical to a player's success. In an attempt to better understand the aspects related to expert performance, researchers have investigated successful free throws and jump shots of various basketball players and identified movement variables that contribute to their success. The purpose of this study was to complete a systematic review of the scientific literature on the basketball free throw and jump shot for the purpose of revealing the critical components of shooting that coaches, teachers, and players should focus on when teaching, learning, practising, and performing a jump shot. The results of this review are presented in three sections: (a) variables that affect ball trajectory, (b) phases of the jump shot, and (c) additional variables that influence shooting.

Investigation of kinematics of knuckling shot in soccer

Science.gov (United States)

Asai, T.; Hong, S.

2017-02-01

In this study, we use four high-speed video cameras to investigate the swing characteristics of the kicking leg while delivering the knuckling shot in soccer. We attempt to elucidate the impact process of the kicking foot at the instant of its impact with the ball and the technical mechanisms of the knuckling shot via comparison of its curved motion with that of the straight and curved shots. Two high-speed cameras (Fastcam, Photron Inc., Tokyo, Japan; 1000 fps, 1024 × 1024 pixels) are set up 2 m away from the site of impact with a line of sight perpendicular to the kicking-leg side. In addition, two semi-high-speed cameras (EX-F1, Casio Computer Co., Ltd., Tokyo, Japan; 300 fps; 720 × 480 pixels) are positioned, one at the rear and the other on the kicking-leg side, to capture the kicking motion. We observe that the ankle joint at impact in the knuckling shot flexes in an approximate L-shape in a manner similar to the joint flexing for the curve shot. The hip's external rotation torque in the knuckling shot is greater than those of other shots, which suggests the tendency of the kicker to push the heel forward and impact with the inside of the foot. The angle of attack in the knuckling shot is smaller than that in other shots, and we speculate that this small attack angle is a factor in soccer kicks which generate shots with smaller rotational frequencies of the ball.

Status of SPring-8 Photocathode Rf Gun for Future Light Sources

CERN Document Server

Tomizawa, H; Dewa, H; Hanaki, H; Kobayashi, T; Mizuno, A; Suzuki, S; Taniuchi, T; Yanagida, K

2005-01-01

We have been studying photocathode single-cell pillbox rf gun for future light sources since 1996. We achieved a rmaximum field gradient of 187 MV/m with chemical-etching processed cavity. We have been developed stable and highly qualified UV-laser source for the rf gun intensively last 3 years. The UV-laser pulse (10 Hz) energy is up to 850 uJ/pulse. The energy stability (rms) of laser has been improved down to 0.2~0.3 % at the fundamental and 0.7~1.3% at the third harmonic generation. This stability is held for two months continuously. In this improvement, we just passively stabilized the system in a humidity-controlled clean room. On the other hand, the ideal spatial and temporal profiles of a shot-by-shot single laser pulse are essential to suppress the emittance growth of the electron beam from the rf gun. We prepared a deformable mirror for spatial shaping, and a spatial light modulator based on fused-silica plates for temporal shaping. With a deformable mirror, we obtained an emittance of1.6

Parametric study on single shot peening by dimensional analysis method incorporated with finite element method

Science.gov (United States)

Wu, Xian-Qian; Wang, Xi; Wei, Yan-Peng; Song, Hong-Wei; Huang, Chen-Guang

2012-06-01

Shot peening is a widely used surface treatment method by generating compressive residual stress near the surface of metallic materials to increase fatigue life and resistance to corrosion fatigue, cracking, etc. Compressive residual stress and dent profile are important factors to evaluate the effectiveness of shot peening process. In this paper, the influence of dimensionless parameters on maximum compressive residual stress and maximum depth of the dent were investigated. Firstly, dimensionless relations of processing parameters that affect the maximum compressive residual stress and the maximum depth of the dent were deduced by dimensional analysis method. Secondly, the influence of each dimensionless parameter on dimensionless variables was investigated by the finite element method. Furthermore, related empirical formulas were given for each dimensionless parameter based on the simulation results. Finally, comparison was made and good agreement was found between the simulation results and the empirical formula, which shows that a useful approach is provided in this paper for analyzing the influence of each individual parameter.

Distortion-free diffusion tensor imaging for evaluation of lumbar nerve roots: Utility of direct coronal single-shot turbo spin-echo diffusion sequence.

Science.gov (United States)

Sakai, Takayuki; Doi, Kunio; Yoneyama, Masami; Watanabe, Atsuya; Miyati, Tosiaki; Yanagawa, Noriyuki

2018-06-01

Diffusion tensor imaging (DTI) based on a single-shot echo planer imaging (EPI-DTI) is an established method that has been used for evaluation of lumbar nerve disorders in previous studies, but EPI-DTI has problems such as a long acquisition time, due to a lot of axial slices, and geometric distortion. To solve these problems, we attempted to apply DTI based on a single-shot turbo spin echo (TSE-DTI) with direct coronal acquisition. Our purpose in this study was to investigate whether TSE-DTI may be more useful for evaluation of lumbar nerve disorders than EPI-DTI. First, lumbar nerve roots of five healthy volunteers were evaluated for optimization of imaging parameters with TSE-DTI including b-values and the number of motion proving gradient (MPG) directions. Subsequently, optimized TSE-DTI was quantitatively compared with conventional EPI-DTI by using fractional anisotropy (FA) values and visual scores in subjective visual evaluation of tractography. Lumbar nerve roots of six patients, who had unilateral neurologic symptoms in one leg, were evaluated by the optimized TSE-DTI. TSE-DTI with b-value of 400 s/mm 2 and 32 diffusion-directions could reduce the image distortion compared with EPI-DTI, and showed that the average FA values on the symptomatic side for six patients were significantly lower than those on the non-symptomatic side (P DTI might show damaged areas of lumbar nerve roots without severe image distortion. TSE-DTI might improve the reproducibility in measurements of FA values for quantification of a nerve disorder, and would become a useful tool for diagnosis of low back pain. Copyright © 2018 Elsevier Inc. All rights reserved.

Ankle Block vs Single-Shot Popliteal Fossa Block as Primary Anesthesia for Forefoot Operative Procedures: Prospective, Randomized Comparison.

Science.gov (United States)

Schipper, Oliver N; Hunt, Kenneth J; Anderson, Robert B; Davis, W Hodges; Jones, Carroll P; Cohen, Bruce E

2017-11-01

Postoperative pain is often difficult to control with oral medications, requiring large doses of opioid analgesia. Regional anesthesia may be used for primary anesthesia, reducing the need for general anesthetic and postoperative pain medication requirements in the immediate postoperative period. The purpose of this study was to compare the analgesic effects of an ankle block (AB) to a single-shot popliteal fossa block (PFB) for patients undergoing orthopedic forefoot procedures. All patients having elective outpatient orthopedic forefoot procedures were invited to participate in the study. Patients were prospectively randomized to receive either an ultrasound-guided AB or PFB by a board-certified anesthesiologist prior to their procedure. Intraoperative conversion to general anesthesia and postanesthesia care unit (PACU) opioid requirements were recorded. Postoperative pain was assessed using the visual analog scale (VAS) at regular time intervals until 8 am on postoperative day (POD) 2. Patients rated the effectiveness of the block on a 1 to 5 scale, with 5 being very effective. A total of 167 patients participated in the study with 88 patients (53%) receiving an AB and 79 (47%) receiving a single-shot PFB. There was no significant difference in the rate of conversion to general anesthesia between the 2 groups (13.6% [12/88] AB vs 12.7% [10/79] PFB). PACU morphine requirements and doses were significantly reduced in the PFB group ( P = .004) when compared to the AB group. The VAS was also significantly lower for the PFB patients at 10 pm on POD 0 (4.6 vs 1.6, P block site pain and/or erythema (AB 6.9% [6/88] vs PFB 5.1% [4/79], P = .44). The analgesic effect of the PFB lasted significantly longer when compared to the ankle block (AB 14.5 hours vs PFB 20.9 hours, P block between the 2 groups, with both blocks being highly effective (AB 4.79/5 vs PFB 4.82/5, P = .68). Regional anesthesia was a safe and reliable adjunct to perioperative pain management and highly

Analysis of shot-to-shot variability in post-disruption runaway electron currents for diverted DIII-D discharges

International Nuclear Information System (INIS)

Izzo, V A; Humphreys, D A; Kornbluth, M

2012-01-01

In DIII-D experiments, rapid termination by Ar-pellet injection sometimes produces a post-termination runaway electron (RE) current plateau, but this effect is highly non-reproducible on a shot-to-shot basis, particularly for diverted target plasmas. A set of DIII-D discharges is analyzed with two MHD codes to understand the relationship between the current profile of the target plasma and the amplitude of the RE current plateau. Using the linear stability code GATO, a correlation between the radial profile of the unstable n = 1 mode just after Ar-pellet injection and the observed appearance of an RE plateau is identified. Nonlinear NIMROD simulations with RE test-particle calculations directly predict RE confinement times during the disruption. With one exception, NIMROD predicts better RE confinement for shots in which higher RE currents were observed in DIII-D. But, the variation in confinement is primarily connected to the saturated n = 1 mode amplitude and not its radial profile. Still, both sets of analyses support the hypothesis that RE deconfinement by MHD fluctuations is a major factor in the shot-to-shot variability of RE plateaus, though additional factors such as seed current amplitude cannot be ruled out. (paper)

Osseointegration improvement by shot peening in titanium dental implants

International Nuclear Information System (INIS)

Aparicio, C.; Gil, F.J.; Planell, J.A.; Padros, A.; Peraire, C.

1998-01-01

In order to optimize the implant-bone fixation, different shot peening treatments with different shot particles (TiO 2 , Al 2 O 3 ; SiC) have been made. The influence that each type of shot particle has in the bone colonization on the different treatment surfaces has been determined by means of osteoblast-like cells culture. Commercially pure titanium discs have been shot peened. Their qualitative and quantitative surface roughness have been characterized; as well as their surface contamination caused by the shot particles. Particle size has also been determined, before and after the treatment, in order to evaluate their breaking averages. Finally, a TiO 2 shot particles manufacture process by sintering has been developed. The manufacture has been necessary since this type of shot particles are not available in the market with the adequate size. (Author) 10 refs

Concrete Cleaning, Inc. centrifugal shot blaster: Baseline report; Summary

International Nuclear Information System (INIS)

1997-01-01

The centrifugal shot blaster is an electronically operated shot-blast machine that removes layer of concrete of varying depths. Hardened steel shot propelled at a high rate of speed abrades the surface of the concrete. The depth of material removed is determined by the rate of speed the machine is traveling and the volume of shot being fired into the blast chamber. The steel shot is reused until it is pulverized to dust, which is deposited in the waste container with the concrete being removed. Debris is continually vacuumed by a large dust collection system attached to the shot blaster. The safety and health evaluation during the human factors assessment focused on two main areas: noise and dust

Efficient 'water window' soft x-ray high-Z plasma source

International Nuclear Information System (INIS)

Higashiguchi, T; Otsuka, T; Jiang, W; Endo, A; Li, B; Dunne, P; O'Sullivan, G

2013-01-01

Unresolved transition array (UTA) is scalable to shorter wavelengths, and we demonstrate a table-top broadband emission 'water window' soft x-ray source based on laser-produced plasmas. Resonance emission from multiply charged ions merges to produce intense UTAs in the 2 to 4 nm region, extending below the carbon K edge (4.37 nm). An outline of a microscope design for single-shot live cell imaging is proposed based on a bismuth (Bi) plasma UTA source, coupled to multilayer mirror optics

Influence of Running on Pistol Shot Hit Patterns.

Science.gov (United States)

Kerkhoff, Wim; Bolck, Annabel; Mattijssen, Erwin J A T

2016-01-01

In shooting scene reconstructions, risk assessment of the situation can be important for the legal system. Shooting accuracy and precision, and thus risk assessment, might be correlated with the shooter's physical movement and experience. The hit patterns of inexperienced and experienced shooters, while shooting stationary (10 shots) and in running motion (10 shots) with a semi-automatic pistol, were compared visually (with confidence ellipses) and statistically. The results show a significant difference in precision (circumference of the hit patterns) between stationary shots and shots fired in motion for both inexperienced and experienced shooters. The decrease in precision for all shooters was significantly larger in the y-direction than in the x-direction. The precision of the experienced shooters is overall better than that of the inexperienced shooters. No significant change in accuracy (shift in the hit pattern center) between stationary shots and shots fired in motion can be seen for all shooters. © 2015 American Academy of Forensic Sciences.

Surface severe plastic deformation of AISI 304 via conventional shot peening, severe shot peening and repeening

Energy Technology Data Exchange (ETDEWEB)

Unal, Okan, E-mail: unalokan78@gmail.com [Mechanical Engineering Department, Bartın University, Bartın 74100 (Turkey); Varol, Remzi [Mechanical Engineering Department, Suleyman Demirel University, Isparta 32200 (Turkey)

2015-10-01

Highlights: • CSP and SSP treatments transform austenite to metastable martensite structure. • Nanograin layer thickness after CSP and SSP is 8 μm and 22 μm, respectively. • Shot peening leads to carbon segregation from coarse to nano grain layer. • Repeening is an effective way to reduce surface roughness. - Abstract: Air blast conventional shot peening (CSP), severe shot peening (SSP) and repeening (RP) as a severe plastic deformation applications on AISI 304 austenitic stainless steel is addressed. Shot peened specimens are investigated based on optical, FESEM and digital microscope. The investigations present the austenite transformation to metastable martensite via mechanical twinning due to plastic deformation with high strain rates. It is found that SSP induces thicker nanograin layer with compared to CSP. In XRD studies, the austenite peaks broaden by means of severe shot peening and FWHM increase reveals the grain size reduction below 25 nm regimes on the surface. In EDAX line analysis of CSP specimen, carbon content increase has been detected from deformed layer through the nanocrystalline layer then the content reduces. The carbon segregation takes place due to the energy level distinction between dislocations and Fe−C bonds. 3d contour digital microscope studies and roughness investigations reveal that SSP has deleterious side effect on the surface roughness and surface flatness. However, RP is an effective way to reduce the surface roughness to reasonable values.

Delineation of spall zone from pre/post shot reflections studies: Preliminary results from BEXAR. Los Alamos Source Region Project

Energy Technology Data Exchange (ETDEWEB)

Taylor, S.R.; Cogbill, A.H.; Weaver, T.A. [Los Alamos National Lab., NM (United States); Miller, R.; Steeples, D. [Kansas Univ., Lawrence, KS (United States)

1992-12-31

In order to delineate the lateral and depth extent of spall from a buried nuclear explosion, we have performed a high-resolution pre- and post-shot seismic reflection survey from BEXAR. Although the data quality were marginal due to poor wave propagation through the volcanic tuffs of Pahute Mesa, a number of interesting differences are observed on the pre- and post-shot surveys. On the pre-shot survey, a reflector (reflector `` 1 ``) is observed at 250 ms (or about 150 m depth) using a stacking velocity of 1300 m/s. On the post-shot survey two reflectors are observed and a stacking velocity of 1150 m/s was used representing a 12% reduction in compressional velocity. With this stacking velocity, reflector `` 1 `` is recorded at 290 ms (still at about 150 m depth) and a new reflector ``2`` is observed at 210 ms (or about 100 m depth). These stacking velocities correspond well with available uphole travel times collected in U19ba and nearby U19ax (BEXAR and KEARSARGE emplacement holes, respectively). The cause for the differences observed in the pre- and post-shot surveys may be due to one of two reasons. First, it is possible that the near-surface rocks were damaged as part of the spallation process (thus reducing the in situ velocities) and reflector ``2`` represents a spall detachment surface. However, analysis of acceleration data collected close to the reflection line suggests that the ground motions were probably inadequate to damage the tuffs. Also, no evidence of actual spallation was actually observed. The second hypothesis is that the near-surface velocities of the tuffs were altered by the change in saturation state due to extensive rains occurring between the pre- and postshot surveys. Although the dependence of seismic velocity on saturation state is controlled by a number of complex factors, it cannot be ruled out.

Photon statistics characterization of a single-photon source

International Nuclear Information System (INIS)

Alleaume, R; Treussart, F; Courty, J-M; Roch, J-F

2004-01-01

In a recent experiment, we reported the time-domain intensity noise measurement of a single-photon source relying on single-molecule fluorescence control. In this paper, we present data processing starting from photocount timestamps. The theoretical analytical expression of the time-dependent Mandel parameter Q(T) of an intermittent single-photon source is derived from ON↔OFF dynamics. Finally, source intensity noise analysis, using the Mandel parameter, is quantitatively compared with the usual approach relying on the time autocorrelation function, both methods yielding the same molecular dynamical parameters

Magnetic resonance urography in pediatrics: utilization of ultrafast single-shot spin echo sequences

International Nuclear Information System (INIS)

Martin, C.; Martin, J.; Duran, C.; Rigol, S.; Rojo, J. C.

1999-01-01

To determine the value of magnetic resonance urography (MRU) using ultrafast single-shot (SS) rapid acquisition with relaxation enhancement (RARE) and half-Fourier (HF) SS-RARE (SS-HF-RARE or HASTE) in the evaluation of congenital urinary tract anomalies in pediatric patients, and their possible application as alternatives to intravenous urography (IVU). Eighteen children (11 boys and 7 girls) aged 2 months to 15 years (mean: 5 years) with a total of 19 congenital urinary tract anomalies were studies by MU using SS-RARE and HASTE sequences in a 1 Tesla scanner. All the patients had previously been studies by ultrasound (US) and IVU. Twelve patients required anesthesia. The images were acquired by means of a HASTE sequence with multisection technique (TR, infinite; TE e f, 87 msec; echo train, 128; interval between echoes, 10.9 msec; total acquisition time, 13 sections/12 seconds), and SS-RARE (TR, infinite; TE e f, 1.100 msec; echo train, 240, and acquisition time, 7 seconds). Four radiologists evaluated the images independently; two who reviewed the IV images in consensus and two who reviewed the MRU images in consensus. The images were evaluated to assess the dilatation of the urinary tract and their utility in detecting the level and cause of the obstruction. MRU images revealed the urinary tract dilation, the level of the obstruction and the type of anomaly in 18 patients (100%), while IVU provided this information in only 10 [ sensitivity, 53%, 95% confidence interval (29%, 76%)]. The mean time required for MRU was 20 minutes (range: 7 to 30 minutes), while that of IVU was 1,242 minutes (range: 45 to 1,440 minutes). MRU using ultrafast single-short spin echo sequences is a rapid and effective technique that permits and excellent evaluation of congenital urinary tract anomalies in pediatric patients and does not require the administration of contrast media or ionizing radiation. (Author) 10 refs

Optimization of mass spectrometric parameters improve the identification performance of capillary zone electrophoresis for single-shot bottom-up proteomics analysis.

Science.gov (United States)

Zhang, Zhenbin; Dovichi, Norman J

2018-02-25

The effects of MS1 injection time, MS2 injection time, dynamic exclusion time, intensity threshold, and isolation width were investigated on the numbers of peptide and protein identifications for single-shot bottom-up proteomics analysis using CZE-MS/MS analysis of a Xenopus laevis tryptic digest. An electrokinetically pumped nanospray interface was used to couple a linear-polyacrylamide coated capillary to a Q Exactive HF mass spectrometer. A sensitive method that used a 1.4 Th isolation width, 60,000 MS2 resolution, 110 ms MS2 injection time, and a top 7 fragmentation produced the largest number of identifications when the CZE loading amount was less than 100 ng. A programmable autogain control method (pAGC) that used a 1.4 Th isolation width, 15,000 MS2 resolution, 110 ms MS2 injection time, and top 10 fragmentation produced the largest number of identifications for CZE loading amounts greater than 100 ng; 7218 unique peptides and 1653 protein groups were identified from 200 ng by using the pAGC method. The effect of mass spectrometer conditions on the performance of UPLC-MS/MS was also investigated. A fast method that used a 1.4 Th isolation width, 30,000 MS2 resolution, 45 ms MS2 injection time, and top 12 fragmentation produced the largest number of identifications for 200 ng UPLC loading amount (6025 unique peptides and 1501 protein groups). This is the first report where the identification number for CZE surpasses that of the UPLC at the 200 ng loading level. However, more peptides (11476) and protein groups (2378) were identified by using UPLC-MS/MS when the sample loading amount was increased to 2 μg with the fast method. To exploit the fast scan speed of the Q-Exactive HF mass spectrometer, higher sample loading amounts are required for single-shot bottom-up proteomics analysis using CZE-MS/MS. Copyright © 2017 Elsevier B.V. All rights reserved.

Collider shot setup for Run 2 observations and suggestions

International Nuclear Information System (INIS)

Annala, J.; Joshel, B.

1996-01-01

This note is intended to provoke discussion on Collider Run II shot setup. We hope this is a start of activities that will converge on a functional description of what is needed for shot setups in Collider Run II. We will draw on observations of the present shot setup to raise questions and make suggestions for the next Collider run. It is assumed that the reader has some familiarity with the Collider operational issues. Shot setup is defined to be the time between the end of a store and the time the Main Control Room declares colliding beams. This is the time between Tevatron clock events SCE and SCB. This definition does not consider the time experiments use to turn on their detectors. This analysis was suggested by David Finley. The operational scenarios for Run II will require higher levels of reliability and speed for shot setup. See Appendix I and II. For example, we estimate that a loss of 3 pb -1 /week (with 8 hour stores) will occur if shot setups take 90 minutes instead of 30 minutes. In other words: If you do 12 shots for one week and accept an added delay of one minute in each shot, you will loose more than 60 nb -1 for that week alone (based on a normal shot setup of 30 minutes). These demands should lead us to be much more pedantic about all the factors that affect shot setups. Shot setup will be viewed as a distinct process that is composed of several inter- dependent 'components': procedures, hardware, controls, and sociology. These components don't directly align with the different Accelerator Division departments, but are topical groupings of the needed accelerator functions. Defining these components, and categorizing our suggestions within them, are part of the goal of this document. Of course, some suggestions span several of these components

Hepatitis A and the Vaccine (Shot) to Prevent It

Science.gov (United States)

... Resources Maternal Immunization Resources Related Links Vaccines & Immunizations Hepatitis A and the Vaccine (Shot) to Prevent It ... the vaccine. Why should my child get the hepatitis A shot? The hepatitis A shot: Protects your ...

Single-photon source engineering using a Modal Method

DEFF Research Database (Denmark)

Gregersen, Niels

Solid-state sources of single indistinguishable photons are of great interest for quantum information applications. The semiconductor quantum dot embedded in a host material represents an attractive platform to realize such a single-photon source (SPS). A near-unity efficiency, defined as the num...... nanowire SPSs...

MR imaging of the gastrointestinal tract with half-fourier single-shot fast spin echo (SSFSE)

International Nuclear Information System (INIS)

Boku, Houjun; Takehara, Yasuo; Isoda, Haruo; Isogai, Satoshi; Kaneko, Masao

1999-01-01

Our objective was to implement a non-invasive magnetic resonance imaging (MRI) technique combined with concentrated milk ingestion for depicting the gastrointestinal (GI) tract and detecting gastrointestinal motility and transit. The half-Fourier SSFSE (single-shot fast spin echo) sequence was optimized on the basis of a phantom study. In order to determine the feasibility of milk ingestion as a substitute for contrast medium, ten human volunteers were examined with SSFSE after two types of liquid ingestion (i.e., milk and water). The snapshot images provided subsecond data acquisition for each coronal plane, allowing visualization of peristalsis in the gastrointestinal tract in an almost real-time fashion, without motion-related image degradation, as would normally be seen using conventional MRI. There was no significant difference between concentrated milk and water in terms of depiction of the upper gastrointestinal tract; however, 10 min and 30 min after ingestion, concentrated milk showed better delineation of the intestine than that observed after water ingestion (p<0.01). MR gastrointestinal imaging is a non-invasive method that allows gastrointestinal depiction as well as analysis of motility and passage. Especially with concentrated milk ingestion, the distal intestines were well depicted with adequate contrast filling and distention. (author)

SunShot Initiative Portfolio Book 2014

Energy Technology Data Exchange (ETDEWEB)

Solar Energy Technologies Office

2014-05-01

The 2014 SunShot Initiative Portfolio Book outlines the progress towards the goals outlined in the SunShot Vision Study. Contents include overviews of each of SunShot’s five subprogram areas, as well as a description of every active project in the SunShot’s project portfolio as of May 2014.

Silicon-Vacancy Spin Qubit in Diamond: A Quantum Memory Exceeding 10 ms with Single-Shot State Readout

Science.gov (United States)

Sukachev, D. D.; Sipahigil, A.; Nguyen, C. T.; Bhaskar, M. K.; Evans, R. E.; Jelezko, F.; Lukin, M. D.

2017-12-01

The negatively charged silicon-vacancy (SiV- ) color center in diamond has recently emerged as a promising system for quantum photonics. Its symmetry-protected optical transitions enable the creation of indistinguishable emitter arrays and deterministic coupling to nanophotonic devices. Despite this, the longest coherence time associated with its electronic spin achieved to date (˜250 ns ) has been limited by coupling to acoustic phonons. We demonstrate coherent control and suppression of phonon-induced dephasing of the SiV- electronic spin coherence by 5 orders of magnitude by operating at temperatures below 500 mK. By aligning the magnetic field along the SiV- symmetry axis, we demonstrate spin-conserving optical transitions and single-shot readout of the SiV- spin with 89% fidelity. Coherent control of the SiV- spin with microwave fields is used to demonstrate a spin coherence time T2 of 13 ms and a spin relaxation time T1 exceeding 1 s at 100 mK. These results establish the SiV- as a promising solid-state candidate for the realization of quantum networks.

Lowering of L10 phase transition temperature of FePt thin films by single shot H+ ion exposure using plasma focus device

International Nuclear Information System (INIS)

Pan, Z.Y.; Lin, J.J.; Zhang, T.; Karamat, S.; Tan, T.L.; Lee, P.; Springham, S.V.; Ramanujan, R.V.; Rawat, R.S.

2009-01-01

FePt thin films are exposed to pulsed energetic H + ion beam from plasma focus. In irradiated films, the phase transition from the low K u disordered face-centered-cubic structure to high K u ordered face-centered-tetragonal phase was achieved at 400 deg. C with the order parameter S ranging from 0.73 to 0.83, high coercivity of about 5356 kA/m, high negative nucleation field of about 7700 kA/m and high squareness ratio ranging from 0.73 to 0.79. The advantage of using plasma focus device is that it can lower phase transition temperature and significantly enhance the magnetic properties by a pulsed single shot exposure

Laser ion source with solenoid field

Science.gov (United States)

Kanesue, Takeshi; Fuwa, Yasuhiro; Kondo, Kotaro; Okamura, Masahiro

2014-11-01

Pulse length extension of highly charged ion beam generated from a laser ion source is experimentally demonstrated. The laser ion source (LIS) has been recognized as one of the most powerful heavy ion source. However, it was difficult to provide long pulse beams. By applying a solenoid field (90 mT, 1 m) at plasma drifting section, a pulse length of carbon ion beam reached 3.2 μs which was 4.4 times longer than the width from a conventional LIS. The particle number of carbon ions accelerated by a radio frequency quadrupole linear accelerator was 1.2 × 1011, which was provided by a single 1 J Nd-YAG laser shot. A laser ion source with solenoid field could be used in a next generation heavy ion accelerator.

Methods for forming particles from single source precursors

Science.gov (United States)

Fox, Robert V [Idaho Falls, ID; Rodriguez, Rene G [Pocatello, ID; Pak, Joshua [Pocatello, ID

2011-08-23

Single source precursors are subjected to carbon dioxide to form particles of material. The carbon dioxide may be in a supercritical state. Single source precursors also may be subjected to supercritical fluids other than supercritical carbon dioxide to form particles of material. The methods may be used to form nanoparticles. In some embodiments, the methods are used to form chalcopyrite materials. Devices such as, for example, semiconductor devices may be fabricated that include such particles. Methods of forming semiconductor devices include subjecting single source precursors to carbon dioxide to form particles of semiconductor material, and establishing electrical contact between the particles and an electrode.

Feasibility study of broadband efficient ''water window'' source

International Nuclear Information System (INIS)

Higashiguchi, Takeshi; Yugami, Noboru; Otsuka, Takamitsu; Jiang Weihua; Endo, Akira; Li Bowen; Dunne, Padraig; O'Sullivan, Gerry

2012-01-01

We demonstrate a table-top broadband emission water window source based on laser-produced high-Z plasmas. Resonance emission from multiply charged ions merges to produce intense unresolved transition arrays (UTAs) in the 2-4 nm region, extending below the carbon K edge (4.37 nm). Arrays resulting from n=4-n=4 transitions are overlaid with n=4-n=5 emission and shift to shorter wavelength with increasing atomic number. An outline of a microscope design for single-shot live cell imaging is proposed based on a bismuth plasma UTA source, coupled to multilayer mirror optics.

27-Level DC–AC inverter with single energy source

International Nuclear Information System (INIS)

Tsang, K.M.; Chan, W.L.

2012-01-01

Highlights: ► This paper reports a novel 27-level DC–AC inverter using only single renewable energy source. ► The efficiency of the inverter is very high. The output waveform is almost sinusoidal. ► The cost is low as the number of power switches required is only 12. - Abstract: A novel design of multilevel DC–AC inverter using only single renewable energy source is presented in this paper. The proposed approach enables multilevel output to be realised by a few cascaded H-bridges and a single energy source. As an illustration, a 27-level inverter has been implemented based on three cascaded H-bridges with a single energy source and two capacitors. Using the proposed novel switching strategy, 27 levels can be realized and the two virtual energy sources can be well regulated. Experimental results are included to demonstrate the effectiveness of the proposed inverter.

Toxicity of Lead and Proposed Substitute Shot to Mallards

Science.gov (United States)

Longcore, J.R.; Andrews, R.; Locke, L.N.; Bagley, George E.; Young, L.T.

1974-01-01

Poisoning of North American waterfowl resulting from the ingestion of lead shot by ducks, geese, and swans causes an estimated annual mortality of 2 to 3% of the population (Bellrose 1959). To alleviate this problem the search for a suitable substitute for lead has been underway since the early 1950's. Proposed substitutes for lead shot were evaluated in a series of acute toxicity tests with pen-reared mallards (Anas platyrhynchos). Most candidate materials were as toxic to ducks as commercial lead shot. Coating or alloying lead with other metals only delayed mortality among dosed ducks. The reputedly 'disintegrable' lead shot with the water-soluble binder and the lead containing biochemical additives were also as toxic to mallards as the commercial lead shot. Mortality was not significantly different among lead-dosed adult or first-year hen and drake pen-reared mallards; lead-dosed adult, wild mallards of both sexes; and lead-dosed adult, male black ducks (Anas rubripes). The ingestion of one lead shot, size 4, by each of 80 pen-reared mallards caused an average 19% mortality. The presence and type of grit in the gizzard had a measurable effect on erosion of ingested shot and on shot retention among dosed mallards. Significantly fewer lead-dosed ducks died when fed crushed oystershell grit than when fed either quartz grit or no grit.

Self-Calibrating Wave-Encoded Variable-Density Single-Shot Fast Spin Echo Imaging.

Science.gov (United States)

Chen, Feiyu; Taviani, Valentina; Tamir, Jonathan I; Cheng, Joseph Y; Zhang, Tao; Song, Qiong; Hargreaves, Brian A; Pauly, John M; Vasanawala, Shreyas S

2018-04-01

It is highly desirable in clinical abdominal MR scans to accelerate single-shot fast spin echo (SSFSE) imaging and reduce blurring due to T 2 decay and partial-Fourier acquisition. To develop and investigate the clinical feasibility of wave-encoded variable-density SSFSE imaging for improved image quality and scan time reduction. Prospective controlled clinical trial. With Institutional Review Board approval and informed consent, the proposed method was assessed on 20 consecutive adult patients (10 male, 10 female, range, 24-84 years). A wave-encoded variable-density SSFSE sequence was developed for clinical 3.0T abdominal scans to enable high acceleration (3.5×) with full-Fourier acquisitions by: 1) introducing wave encoding with self-refocusing gradient waveforms to improve acquisition efficiency; 2) developing self-calibrated estimation of wave-encoding point-spread function and coil sensitivity to improve motion robustness; and 3) incorporating a parallel imaging and compressed sensing reconstruction to reconstruct highly accelerated datasets. Image quality was compared pairwise with standard Cartesian acquisition independently and blindly by two radiologists on a scale from -2 to 2 for noise, contrast, confidence, sharpness, and artifacts. The average ratio of scan time between these two approaches was also compared. A Wilcoxon signed-rank tests with a P value under 0.05 considered statistically significant. Wave-encoded variable-density SSFSE significantly reduced the perceived noise level and improved the sharpness of the abdominal wall and the kidneys compared with standard acquisition (mean scores 0.8, 1.2, and 0.8, respectively, P variable-density sampling SSFSE achieves improved image quality with clinically relevant echo time and reduced scan time, thus providing a fast and robust approach for clinical SSFSE imaging. 1 Technical Efficacy: Stage 6 J. Magn. Reson. Imaging 2018;47:954-966. © 2017 International Society for Magnetic Resonance in Medicine.

Lead isotopes and lead shot ingestion in the globally threatened marbled teal (Marmaronetta angustirostris) and white-headed duck (Oxyura leucocephala)

International Nuclear Information System (INIS)

Svanberg, Fredrik; Mateo, Rafael; Hillstroem, Lars; Green, Andy J.; Taggart, Mark A.; Raab, Andrea; Meharg, Andy A.

2006-01-01

Lead isotope ratios ( 206 Pb/ 207 Pb and 208 Pb/ 207 Pb) and concentrations in the livers and bones of marbled teal and white-headed duck found dead or moribund were determined in order to establish the main lead source in these waterfowl species. Lead concentrations in bone (dry weight) and liver (wet weight) were found to be very high in many of the white-headed ducks (bone: geometric mean = 88.9 ppm, maximum = 419 ppm; liver: geometric mean = 16.8 ppm, maximum = 57.0 ppm). Some of the marbled teal had high lead levels in the bones but liver lead levels were all low (bone: geometric mean = 6.13 ppm, maximum = 112 ppm; liver: geometric mean = 0.581 ppm, maximum = 4.77 ppm). Ingested lead shot were found in 71% of the white-headed duck and 20% of the marbled teal. The 206 Pb/ 207 Pb ratio in livers and bones of white-headed ducks and marbled teals showed no significant differences compared to the ratios obtained from lead shot. The 206 Pb/ 207 Pb ratio in bones of marbled teal ducklings with the highest lead concentrations tended to resemble the ratios of lead shot, which supports our hypothesis that the lead was derived from the hens. We also found that the lead ratios of lead shot and lead ratios described for soils in the area overlapped, but also that the isotopic ratio 206 Pb/ 207 Pb in lead shot used in Spain has a narrow range compared with those used in North America. The principal source of lead in many of these birds was, however, most likely lead shot, as supported by the similar isotopic ratios, high lead concentrations in tissues and evidence of ingested shot

Lead isotopes and lead shot ingestion in the globally threatened marbled teal (Marmaronetta angustirostris) and white-headed duck (Oxyura leucocephala)

Energy Technology Data Exchange (ETDEWEB)

Svanberg, Fredrik [Department of Environmental Toxicology, Evolutionary Biology Centre, Uppsala University, Norbyvaegen 18A, SE-752 36 Uppsala (Sweden)]. E-mail: fredriksvanberg@hotmail.com; Mateo, Rafael [Instituto de Investigacion en Recursos Cinegeticos, IREC (CSIC-UCLM-JCCM), Ronda de Toledo s/n, 13071 Ciudad Real (Spain); Hillstroem, Lars [Institute of Maths, Natural and Computer Science, University of Gaevle, SE-801 76 Gaevle (Sweden); Green, Andy J. [Wetland Ecology Group, Estacion Biologica de Donana-CSIC, Pabellon del Peru, Avenida Maria Luisa s/n, E-40013 Seville (Spain); Taggart, Mark A. [School of Biological Sciences, University of Aberdeen, Cruickshank Bld, St Machar Dr, Aberdeen, Scotland, AB24 3UU (United Kingdom); Raab, Andrea [School of Biological Sciences, University of Aberdeen, Cruickshank Bld, St Machar Dr, Aberdeen, Scotland, AB24 3UU (United Kingdom); Meharg, Andy A. [School of Biological Sciences, University of Aberdeen, Cruickshank Bld, St Machar Dr, Aberdeen, Scotland, AB24 3UU (United Kingdom)

2006-11-01

Lead isotope ratios ({sup 206}Pb/{sup 207}Pb and {sup 208}Pb/{sup 207}Pb) and concentrations in the livers and bones of marbled teal and white-headed duck found dead or moribund were determined in order to establish the main lead source in these waterfowl species. Lead concentrations in bone (dry weight) and liver (wet weight) were found to be very high in many of the white-headed ducks (bone: geometric mean = 88.9 ppm, maximum = 419 ppm; liver: geometric mean = 16.8 ppm, maximum = 57.0 ppm). Some of the marbled teal had high lead levels in the bones but liver lead levels were all low (bone: geometric mean = 6.13 ppm, maximum = 112 ppm; liver: geometric mean = 0.581 ppm, maximum = 4.77 ppm). Ingested lead shot were found in 71% of the white-headed duck and 20% of the marbled teal. The {sup 206}Pb/{sup 207}Pb ratio in livers and bones of white-headed ducks and marbled teals showed no significant differences compared to the ratios obtained from lead shot. The {sup 206}Pb/{sup 207}Pb ratio in bones of marbled teal ducklings with the highest lead concentrations tended to resemble the ratios of lead shot, which supports our hypothesis that the lead was derived from the hens. We also found that the lead ratios of lead shot and lead ratios described for soils in the area overlapped, but also that the isotopic ratio {sup 206}Pb/{sup 207}Pb in lead shot used in Spain has a narrow range compared with those used in North America. The principal source of lead in many of these birds was, however, most likely lead shot, as supported by the similar isotopic ratios, high lead concentrations in tissues and evidence of ingested shot.

One-shot synesthesia

Directory of Open Access Journals (Sweden)

Kirschner Alexandra

2017-11-01

Full Text Available Synesthesia is commonly thought to be a phenomenon of fixed associations between an outside inducer and a vivid concurrent experience. Hence, it has been proposed that synesthesia occurs due to additional connections in the brain with which synesthetes are born. Here we show that synesthesia can be a much richer and more flexible phenomenon with a capability to creatively construct novel synesthetic experiences as events unfold in people’s lives. We describe here cases of synesthetes who occasionally generate novel synesthetic experience, called one-shot synesthesias. These synesthetic experiences seem to share all the properties with the classical synesthetic associations except that they occur extremely rarely, people recalling only a few events over the lifetime. It appears that these one-shots are not created at random but are instead responses to specific life events. We contrast the properties of those rare synesthetic events with other, more commonly known forms of synesthesia that also create novel synesthetic experiences, but at a high rate—sometimes creating novel experiences every few seconds. We argue that one-shot synesthesias indicate that synesthetic associations are by their nature not prewired at birth but are dynamically constructed through mental operations and according to the needs of a synesthetic mind. Our conclusions have implications for understanding the biological underpinnings of synesthesia and the role the phenomenon plays in the lives of people endowed with synesthetic capacities.

Spent shot availability and ingestion on areas managed for mourning doves

Science.gov (United States)

Schulz, J.H.; Millspaugh, J.J.; Washburn, B.E.; Wester, G.R.; Lanigan, J. T.; Franson, J.C.

2002-01-01

Mourning dove (Zenaida macroura) hunting is becoming increasingly popular, especially in managed shooting fields. Given the possible increase in the availability of lead (Pb) shot on these areas, our objective was to estimate availability and ingestion of spent shot at the Eagle Bluffs Conservation Area (EBCA, hunted with nontoxic shot) and the James A. Reed Memorial Wildlife Area (JARWA, hunted with Pb shot) in Missouri. During 1998, we collected soil samples one or 2 weeks prior to the hunting season (prehunt) and after 4 days of dove hunting (posthunt). We also collected information on number of doves harvested, number of shots fired, shotgun gauge, and shotshell size used. Dove carcasses were collected on both areas during 1998-99. At EBCA, 60 hunters deposited an estimated 64,775 pellets/ha of nontoxic shot on or around the managed field. At JARWA, approximately 1,086,275 pellets/ha of Pb shot were deposited by 728 hunters. Our posthunt estimates of spent-shot availability from soil sampling were 0 pellets/ha for EBCA and 6,342 pellets/ha for JARWA. Our findings suggest that existing soil sampling protocols may not provide accurate estimates of spent-shot availability in managed dove shooting fields. During 1998-99, 15 of 310 (4.8%) mourning doves collected from EBCA had ingested nontoxic shot. Of those doves, 6 (40.0%) contained a?Y7 shot pellets. In comparison, only 2 of 574 (0.3%) doves collected from JARWA had ingested Pb shot. Because a greater proportion of doves ingested multiple steel pellets compared to Pb pellets, we suggest that doves feeding in fields hunted with Pb shot may succumb to acute Pb toxicosis and thus become unavailable to harvest, resulting in an underestimate of ingestion rates. Although further research is needed to test this hypothesis, our findings may partially explain why previous studies have shown few doves with ingested Pb shot despite their feeding on areas with high Pb shot availability.

Light emission probing quantum shot noise and charge fluctuations at a biased molecular junction

DEFF Research Database (Denmark)

Schneider, N.L.; Lu, Jing Tao; Brandbyge, M.

2012-01-01

The emission of plasmonic light from a single C60 molecule on Cu(111) is probed in a scanning tunneling microscope from the weak-coupling, tunneling range to strong coupling of the molecule to the electrodes at contact. At positive sample voltage the photon yield decreases owing to shot...

Removal of Retained Lead Shot Through Laparoscopic Appendectomy

Science.gov (United States)

Lloyd, D. M.

2003-01-01

We describe a patient presenting with lead shot in his appendix. A plain radiograph of his lumbar spine was performed for back pain, and an incidental finding of lead shot retained within the appendix was seen. Lead shot in the appendix is associated with appendicitis, and 2 cases have been reported of lead intoxication. We suggest that an elective laparoscopic appendectomy should be offered to patients as a possible management option. PMID:12856854

Shot-Noise Limited Time-Encoded Raman Spectroscopy

Directory of Open Access Journals (Sweden)

Sebastian Karpf

2017-01-01

Full Text Available Raman scattering, an inelastic scattering mechanism, provides information about molecular excitation energies and can be used to identify chemical compounds. Albeit being a powerful analysis tool, especially for label-free biomedical imaging with molecular contrast, it suffers from inherently low signal levels. This practical limitation can be overcome by nonlinear enhancement techniques like stimulated Raman scattering (SRS. In SRS, an additional light source stimulates the Raman scattering process. This can lead to orders of magnitude increase in signal levels and hence faster acquisition in biomedical imaging. However, achieving a broad spectral coverage in SRS is technically challenging and the signal is no longer background-free, as either stimulated Raman gain (SRG or loss (SRL is measured, turning a sensitivity limit into a dynamic range limit. Thus, the signal has to be isolated from the laser background light, requiring elaborate methods for minimizing detection noise. Here, we analyze the detection sensitivity of a shot-noise limited broadband stimulated time-encoded Raman (TICO-Raman system in detail. In time-encoded Raman, a wavelength-swept Fourier domain mode locking (FDML laser covers a broad range of Raman transition energies while allowing a dual-balanced detection for lowering the detection noise to the fundamental shot-noise limit.

[Contact shot from infantry weapons with a flash-suppressor].

Science.gov (United States)

Perdekamp, Markus Grosse; Braunwarth, Roland; Schmidt, Ulrike; Schmidt, Wolfgang; Pollak, Stefan

2003-01-01

The number of reports on contact shots from firearms with a flash suppressor attached to the muzzle is small. On the basis of a case report (suicidal shot to the forehead with a Kalschnikow AKMS 47 assault rifle) the morphological peculiarities (characteristics soot pattern, relatively small powder cavity and only minor skin tears in the presence of a bony support) are presented and the conclusions to be drawn from the findings regarding the flash-suppressor, the shot distance, the angle of the shot and the way of holding the weapon are discussed.

Laser ion source with solenoid field

International Nuclear Information System (INIS)

Kanesue, Takeshi; Okamura, Masahiro; Fuwa, Yasuhiro; Kondo, Kotaro

2014-01-01

Pulse length extension of highly charged ion beam generated from a laser ion source is experimentally demonstrated. The laser ion source (LIS) has been recognized as one of the most powerful heavy ion source. However, it was difficult to provide long pulse beams. By applying a solenoid field (90 mT, 1 m) at plasma drifting section, a pulse length of carbon ion beam reached 3.2 μs which was 4.4 times longer than the width from a conventional LIS. The particle number of carbon ions accelerated by a radio frequency quadrupole linear accelerator was 1.2 × 10 11 , which was provided by a single 1 J Nd-YAG laser shot. A laser ion source with solenoid field could be used in a next generation heavy ion accelerator

Laser ion source with solenoid field

Energy Technology Data Exchange (ETDEWEB)

Kanesue, Takeshi, E-mail: tkanesue@bnl.gov; Okamura, Masahiro [Collider-Accelerator Department, Brookhaven National Laboratory, Upton, New York 11973 (United States); Fuwa, Yasuhiro [Graduate School of Science, Kyoto University, Kitashirakawa, Sakyo, Kyoto 606-7501 (Japan); RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Kondo, Kotaro [Research Laboratory for Nuclear Reactors, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro, Tokyo 152-8550 (Japan)

2014-11-10

Pulse length extension of highly charged ion beam generated from a laser ion source is experimentally demonstrated. The laser ion source (LIS) has been recognized as one of the most powerful heavy ion source. However, it was difficult to provide long pulse beams. By applying a solenoid field (90 mT, 1 m) at plasma drifting section, a pulse length of carbon ion beam reached 3.2 μs which was 4.4 times longer than the width from a conventional LIS. The particle number of carbon ions accelerated by a radio frequency quadrupole linear accelerator was 1.2 × 10{sup 11}, which was provided by a single 1 J Nd-YAG laser shot. A laser ion source with solenoid field could be used in a next generation heavy ion accelerator.

Shot noise reduction in the AlGaAs/GaAs- and InGaP/GaAs-based HBTs

Science.gov (United States)

Sakalas, Paulius; Schroeter, Michael; Zampardi, Peter; Zirath, Herbert

2003-05-01

Noise parameters of AlGaAs/GaAs and InGaP/GaAs HBTs were measured in microwave frequency range and modeled using the small-signal equivalent circuit approach. Correlated current noise sources in the base and collector currents with thermal noise in the circuit resistive elements were accounted for by the model and yielded good agreement with the measured data. This enabled an extraction of the different noise source contributions to minimum noise figure (NFmin) in AlGaAs/GaAs and InGaP/GaAs HBTs. Decomposition of the (NFmin) in to the different contributors showed that the main noise sources in investigated HBTs are correlated base and collector current shot noise. The observed minimum of NFmin versus frequency at lower collector current is explained by the reduction of the emitter/base junction shot noise component due to the spike in the emitter/base junction and associated accumulation of the quasi-thermalized electrons forming a space charge, which screens the electron transfer through the barrier. The bias (VCE) increase creates an efficient electric field in collector/base junction, capable of 'washing out' the accumulated charge. Such shot noise reduction in HBTs could be exploited in the LNA for the RF application.

Highly efficient sources of single indistinguishable photons

DEFF Research Database (Denmark)

Gregersen, Niels

2013-01-01

be electrically driven. Several design strategies addressing these requirements have been proposed. In the cavity-based source, light emission is controlled using resonant cavity quantum electrodynamics effects, whereas in the waveguide-based source, broadband electric field screening effects are employed......Solid-state sources capable of emitting single photons on demand are of great interest in quantum information applications. Ideally, such a source should emit exactly one photon into the collection optics per trigger, the emitted photons should be indistinguishable and the source should...

Evaluating laser-driven Bremsstrahlung radiation sources for imaging and analysis of nuclear waste packages.

Science.gov (United States)

Jones, Christopher P; Brenner, Ceri M; Stitt, Camilla A; Armstrong, Chris; Rusby, Dean R; Mirfayzi, Seyed R; Wilson, Lucy A; Alejo, Aarón; Ahmed, Hamad; Allott, Ric; Butler, Nicholas M H; Clarke, Robert J; Haddock, David; Hernandez-Gomez, Cristina; Higginson, Adam; Murphy, Christopher; Notley, Margaret; Paraskevoulakos, Charilaos; Jowsey, John; McKenna, Paul; Neely, David; Kar, Satya; Scott, Thomas B

2016-11-15

A small scale sample nuclear waste package, consisting of a 28mm diameter uranium penny encased in grout, was imaged by absorption contrast radiography using a single pulse exposure from an X-ray source driven by a high-power laser. The Vulcan laser was used to deliver a focused pulse of photons to a tantalum foil, in order to generate a bright burst of highly penetrating X-rays (with energy >500keV), with a source size of <0.5mm. BAS-TR and BAS-SR image plates were used for image capture, alongside a newly developed Thalium doped Caesium Iodide scintillator-based detector coupled to CCD chips. The uranium penny was clearly resolved to sub-mm accuracy over a 30cm(2) scan area from a single shot acquisition. In addition, neutron generation was demonstrated in situ with the X-ray beam, with a single shot, thus demonstrating the potential for multi-modal criticality testing of waste materials. This feasibility study successfully demonstrated non-destructive radiography of encapsulated, high density, nuclear material. With recent developments of high-power laser systems, to 10Hz operation, a laser-driven multi-modal beamline for waste monitoring applications is envisioned. Copyright © 2016. Published by Elsevier B.V.

What You Can Expect with a Cortisone Shot

Science.gov (United States)

... should avoid before your cortisone shot. What you can expect During the cortisone shot Your doctor might ... ll then be positioned so that your doctor can easily insert the needle. The area around the ...

A singly charged ion source for radioactive 11C ion acceleration

Science.gov (United States)

Katagiri, K.; Noda, A.; Nagatsu, K.; Nakao, M.; Hojo, S.; Muramatsu, M.; Suzuki, K.; Wakui, T.; Noda, K.

2016-02-01

A new singly charged ion source using electron impact ionization has been developed to realize an isotope separation on-line system for simultaneous positron emission tomography imaging and heavy-ion cancer therapy using radioactive 11C ion beams. Low-energy electron beams are used in the electron impact ion source to produce singly charged ions. Ionization efficiency was calculated in order to decide the geometric parameters of the ion source and to determine the required electron emission current for obtaining high ionization efficiency. Based on these considerations, the singly charged ion source was designed and fabricated. In testing, the fabricated ion source was found to have favorable performance as a singly charged ion source.

Some properties of focus points in one-shot decision theory

OpenAIRE

Guo, Peijun

2011-01-01

One-shot (one-time) decision problems concern the situations where a decision is experienced only once. Such one-shot decision problems are commonly encountered in business, economics and social systems. One-shot decision theory has been initially proposed by Guo [4]. The one-shot decision procedure comprises two steps. In the first step, a decision maker identifies which state of nature should be taken into account for each alternative amongst all available states of nature. These identified...

A novel high-efficiency single-mode quantum dot single photon source

DEFF Research Database (Denmark)

Gerard, J.M.; Gregersen, Niels; Nielsen, Torben Roland

2008-01-01

We present a novel single-mode single photon source exploiting the emission of a semiconductor quantum dot (QD) located inside a photonic wire. Besides an excellent coupling (>95%) of QD spontaneous emission to the fundamental guided mode [1], we show that a single photon collection efficiency...... above 80% within a 0.5 numerical aperture can be achieved using a bottom Bragg mirror and a tapering of the nanowire tip. Because this photon collection strategy does not exploit the Purcell effect, it could also be efficiently applied to broadband single photon emitters such as F-centers in diamond....

Comparison of optimization algorithms for the slow shot phase in HPDC

Science.gov (United States)

Frings, Markus; Berkels, Benjamin; Behr, Marek; Elgeti, Stefanie

2018-05-01

High-pressure die casting (HPDC) is a popular manufacturing process for aluminum processing. The slow shot phase in HPDC is the first phase of this process. During this phase, the molten metal is pushed towards the cavity under moderate plunger movement. The so-called shot curve describes this plunger movement. A good design of the shot curve is important to produce high-quality cast parts. Three partially competing process goals characterize the slow shot phase: (1) reducing air entrapment, (2) avoiding temperature loss, and (3) minimizing oxide caused by the air-aluminum contact. Due to the rough process conditions with high pressure and temperature, it is hard to design the shot curve experimentally. There exist a few design rules that are based on theoretical considerations. Nevertheless, the quality of the shot curve design still depends on the experience of the machine operator. To improve the shot curve it seems to be natural to use numerical optimization. This work compares different optimization strategies for the slow shot phase optimization. The aim is to find the best optimization approach on a simple test problem.

3-D analysis of fatigue crack behaviour in a shot peened steam turbine blade material

Energy Technology Data Exchange (ETDEWEB)

He, B.Y., E-mail: Binyan.he@soton.ac.uk [Engineering Materials, Faculty of Engineering and the Environment, University of Southampton, Southampton SO17 1BJ (United Kingdom); Katsamenis, O.L. [muVIS X-ray Imaging Centre, Faculty of Engineering and the Environment, University of Southampton, Southampton SO17 1BJ (United Kingdom); Mellor, B.G.; Reed, P.A.S. [Engineering Materials, Faculty of Engineering and the Environment, University of Southampton, Southampton SO17 1BJ (United Kingdom)

2015-08-26

Serial mechanical sectioning and high resolution X-ray tomography have been used to study the three-dimensional morphology of small fatigue cracks growing in a 12 Cr tempered martensitic steam turbine blade material. A range of surface conditions has been studied, namely polished and shot peened (with varying levels of intensity). In the polished (unpeened) condition, inclusions (alumina and manganese sulphide) played an important role in initiating and controlling early fatigue crack behaviour. When fatigue cracks initiated from an alumina stringer, the crack morphology was normally dominated by single stringers, which were always in the centre of the fatigue crack, indicating its primary role in initiation. Manganese sulphide inclusion groups however seemed to dominate and affect the crack path along both the surface and depth crack growth directions. The more intensely shot peened condition did not however evidence inclusion or stringer affected fatigue crack initiation or growth behaviour; sub-surface crack coalescence being clearly observed by both serial sectioning and computed tomography (CT) imaging techniques at a depth of about 150–180 μm. These sub-surface crack coalescences can be linked to both the extent of the compressive residual stress as well as the depth of the plastic deformation arising from the intense shot peening process. Shot peening appears to provide a different defect population that initiates fatigue cracks and competes with the underlying metallurgical defect populations. The most beneficial shot peening process would in this case appear to “deactivate” the original metallurgical defect population and substitute a known defect distribution from the shot peening process from which fatigue cracks grow rather slowly in the strain hardened surface layer which also contains compressive residual stresses. A benefit to fatigue life in bending, even under Low Cycle Fatigue (LCF) conditions, has been observed in these tests if a

Communication: The electronic structure of matter probed with a single femtosecond hard x-ray pulse

Directory of Open Access Journals (Sweden)

J. Szlachetko

2014-03-01

Full Text Available Physical, biological, and chemical transformations are initiated by changes in the electronic configuration of the species involved. These electronic changes occur on the timescales of attoseconds (10−18 s to femtoseconds (10−15 s and drive all subsequent electronic reorganization as the system moves to a new equilibrium or quasi-equilibrium state. The ability to detect the dynamics of these electronic changes is crucial for understanding the potential energy surfaces upon which chemical and biological reactions take place. Here, we report on the determination of the electronic structure of matter using a single self-seeded femtosecond x-ray pulse from the Linac Coherent Light Source hard x-ray free electron laser. By measuring the high energy resolution off-resonant spectrum (HEROS, we were able to obtain information about the electronic density of states with a single femtosecond x-ray pulse. We show that the unoccupied electronic states of the scattering atom may be determined on a shot-to-shot basis and that the measured spectral shape is independent of the large intensity fluctuations of the incoming x-ray beam. Moreover, we demonstrate the chemical sensitivity and single-shot capability and limitations of HEROS, which enables the technique to track the electronic structural dynamics in matter on femtosecond time scales, making it an ideal probe technique for time-resolved X-ray experiments.

Biomechanical Analysis of the Jump Shot in Basketball

Directory of Open Access Journals (Sweden)

Struzik Artur

2014-10-01

Full Text Available Basketball players usually score points during the game using the jump shot. For this reason, the jump shot is considered to be the most important element of technique in basketball and requires a high level of performance. The aim of this study was to compare the biomechanical characteristics of the lower limbs during a jump shot without the ball and a countermovement jump without an arm swing. The differences between variables provide information about the potential that an athlete can utilise during a game when performing a jump shot. The study was conducted among 20 second-league basketball players by means of a Kistler force plate and the BTS SMART system for motion analysis. The variables measured included the take-off time, mean power, peak power, relative mean power, jump height, maximum landing force and calculated impact ratio. Surprisingly, more advantageous variables were found for the jump shot. This finding suggests a very high performance level in the jump shot in the studied group and a maximum utilisation of their motor abilities. Both types of jumps were characterised by high mean and peak power values and average heights. The high forces at landing, which result in considerable impact ratios, may have prompted the studied group to land softly. Use of the countermovement jump without an arm swing is recommended to assess and predict the progression of player’s jumping ability

Single-channel source separation using non-negative matrix factorization

DEFF Research Database (Denmark)

Schmidt, Mikkel Nørgaard

-determined and its solution relies on making appropriate assumptions concerning the sources. This dissertation is concerned with model-based probabilistic single-channel source separation based on non-negative matrix factorization, and consists of two parts: i) three introductory chapters and ii) five published...... papers. The first part introduces the single-channel source separation problem as well as non-negative matrix factorization and provides a comprehensive review of existing approaches, applications, and practical algorithms. This serves to provide context for the second part, the published papers......, in which a number of methods for single-channel source separation based on non-negative matrix factorization are presented. In the papers, the methods are applied to separating audio signals such as speech and musical instruments and separating different types of tissue in chemical shift imaging....

Single channel blind source separation based on ICA feature extraction

Institute of Scientific and Technical Information of China (English)

无

2007-01-01

A new technique is proposed to solve the blind source separation (BSS) given only a single channel observation. The basis functions and the density of the coefficients of source signals learned by ICA are used as the prior knowledge. Based on the learned prior information the learning rules of single channel BSS are presented by maximizing the joint log likelihood of the mixed sources to obtain source signals from single observation,in which the posterior density of the given measurements is maximized. The experimental results exhibit a successful separation performance for mixtures of speech and music signals.

Protecting single-photon entanglement with practical entanglement source

Science.gov (United States)

Zhou, Lan; Ou-Yang, Yang; Wang, Lei; Sheng, Yu-Bo

2017-06-01

Single-photon entanglement (SPE) is important for quantum communication and quantum information processing. However, SPE is sensitive to photon loss. In this paper, we discuss a linear optical amplification protocol for protecting SPE. Different from the previous protocols, we exploit the practical spontaneous parametric down-conversion (SPDC) source to realize the amplification, for the ideal entanglement source is unavailable in current quantum technology. Moreover, we prove that the amplification using the entanglement generated from SPDC source as auxiliary is better than the amplification assisted with single photons. The reason is that the vacuum state from SPDC source will not affect the amplification, so that it can be eliminated automatically. This protocol may be useful in future long-distance quantum communications.

Study on Plastic Deformation Characteristics of Shot Peening of Ni-Based Superalloy GH4079

Science.gov (United States)

Zhong, L. Q.; Liang, Y. L.; Hu, H.

2017-09-01

In this paper, the X-ray stress diffractometer, surface roughness tester, field emission scanning electron microscope(SEM), dynamic ultra-small microhardness tester were used to measure the surface residual stress and roughness, topography and surface hardness changes of GH4079 superalloy, which was processed by metallographic grinding, turning, metallographic grinding +shot peening and turning + shot peening. Analysized the effects of shot peening parameters on shot peening plastic deformation features; and the effects of the surface state before shot peening on shot peening plastic deformation characteristics. Results show that: the surface residual compressive stress, surface roughness and surface hardness of GH4079 superalloy were increased by shot peening, in addition, the increment of the surface residual compressive stress, surface roughness and surface hardness induced by shot peening increased with increasing shot peening intensity, shot peening time, shot peening pressure and shot hardness, but harden layer depth was not affected considerably. The more plastic deformation degree of before shot peening surface state, the less increment of the surface residual compressive stress, surface roughness and surface hardness induced by shot peening.

Equivalent properties of single event burnout induced by different sources

International Nuclear Information System (INIS)

Yang Shiyu; Cao Zhou; Da Daoan; Xue Yuxiong

2009-01-01

The experimental results of single event burnout induced by heavy ions and 252 Cf fission fragments in power MOSFET devices have been investigated. It is concluded that the characteristics of single event burnout induced by 252 Cf fission fragments is consistent to that in heavy ions. The power MOSFET in the 'turn-off' state is more susceptible to single event burnout than it is in the 'turn-on' state. The thresholds of the drain-source voltage for single event burnout induced by 173 MeV bromine ions and 252 Cf fission fragments are close to each other, and the burnout cross section is sensitive to variation of the drain-source voltage above the threshold of single event burnout. In addition, the current waveforms of single event burnouts induced by different sources are similar. Different power MOSFET devices may have different probabilities for the occurrence of single event burnout. (authors)

Equitable Prices of Single-Source Drugs in Thailand.

Science.gov (United States)

Ngorsuraches, Surachat; Chaiyakan, Kanokkan

2015-08-01

In Thailand, total drug expenditure has grown rapidly. Recently, the Thai government has addressed the issue of drug pricing, but the prices of single-source drugs remain a major challenge. To examine equitable prices of single-source drugs in Thailand. A total of 98 single-source and high-expenditure drugs were examined. Unit prices from the Drug and Medical Supplies Information Center (DMSIC) and National Average Drug Acquisition Cost (NADAC) were used to represent drug prices at the provider level in Thailand and the U.S., respectively. Data for measuring drug affordability, e.g., dose and poverty line, were obtained from Micromedex online and the National Statistical Office (NSO). The U.S. drug prices were adjusted by the Human Development Index (HDI) to be equitable prices for Thailand. Purchasing Power Parity (PPP) was used to convert US currency into Thai baht. All prices in this study were based on the year 2012. Catastrophic, Impoverishment, and WHO/Health Action International (HAI) approaches were used to determine Thai citizens' ability to afford the study drugs. Finally, uncertainty analyses were conducted. From all study drugs, 55 single-source drugs were priced higher than their equitable prices, ranging from 0.38 to 422.36% higher. Among these, 28 items were antineoplastic drugs. The prices of drugs outside the National List of Essential Medicines (NLEM), as well as the country's newer drugs, tended to be higher than their calculated equitable prices. The majority of drugs in Thailand priced higher than equitable prices were unaffordable for most Thai citizens. The uncertainty analyses revealed that almost all results were relatively robust. Most single-source drug prices in Thailand were higher than their equitable prices, and were likely to be unaffordable to Thai citizens.

High-quality asynchronous heralded single-photon source at telecom wavelength

International Nuclear Information System (INIS)

Fasel, Sylvain; Alibart, Olivier; Tanzilli, Sebastien; Baldi, Pascal; Beveratos, Alexios; Gisin, Nicolas; Zbinden, Hugo

2004-01-01

We report on the experimental realization and characterization of an asynchronous heralded single-photon source based on spontaneous parametric down-conversion. Photons at 1550 nm are heralded as being inside a single-mode fibre with more than 60% probability, and the multi-photon emission probability is reduced by a factor of up to more than 500 compared to Poissonian light sources. These figures of merit, together with the choice of telecom wavelength for the heralded photons, are compatible with practical applications needing very efficient and robust single-photon sources

Value of MR cisternography using three-dimensional half-fourier single-shot fast spin-echo sequences in the diagnosis of diseases related to cranial nerves VII and VIII

Energy Technology Data Exchange (ETDEWEB)

Yamakami, Norio [Kyorin Univ., Mitaka, Tokyo (Japan). School of Medicine

1999-05-01

The purpose of this study was to evaluate the value of MR cisternography using three-dimensional half-Fourier single-shot fast spin-echo sequences in the diagnosis of diseasea related to cranial nerves VII and VIII. With a 0.5-T imager, the most appropriate setting of echo time and section thickness was first assessed in five volunteers. This resulted in echo time of 250 msec and section thickness of 2 mm as the most effective parameters. Second, using echo time of 120 msec and section thickness of 1.5 mm that were available from the beginning of this study, the demonstration of four nerves within the audistory canal was assessed in seven volunteers. In all of the volunteers, the facial, cochlear, and vestibular nerves were determined with demonstration of each of superior and inferior vestibular nerves in four of them. Next, MR cisternography using the same echo time and section thickness was applied in 368 patients with suspicion of acoustic neurinoma and 14 with hemifacial spasm. In 28 of the 368 patients, MR cisternograms depicted an acoustic neurinoma that was confirmed on postcontrast T1-weighted images. Meanwhile, in five of the 14 patients with hemifacial spasm, MR cisternograms revealed a vessel compressing the root exit zone of the affected facial nerve. It is concluded that MR cisternography using three-dimensional half-Fourier single-shot fast spin-echo sequences can be a useful means for demonstrating nerves within the auditory nerve as well as for the screening of acoustic neurionoma. (author)

Value of MR cisternography using three-dimensional half-fourier single-shot fast spin-echo sequences in the diagnosis of diseases related to cranial nerves VII and VIII

International Nuclear Information System (INIS)

Yamakami, Norio

1999-01-01

The purpose of this study was to evaluate the value of MR cisternography using three-dimensional half-Fourier single-shot fast spin-echo sequences in the diagnosis of diseasea related to cranial nerves VII and VIII. With a 0.5-T imager, the most appropriate setting of echo time and section thickness was first assessed in five volunteers. This resulted in echo time of 250 msec and section thickness of 2 mm as the most effective parameters. Second, using echo time of 120 msec and section thickness of 1.5 mm that were available from the beginning of this study, the demonstration of four nerves within the audistory canal was assessed in seven volunteers. In all of the volunteers, the facial, cochlear, and vestibular nerves were determined with demonstration of each of superior and inferior vestibular nerves in four of them. Next, MR cisternography using the same echo time and section thickness was applied in 368 patients with suspicion of acoustic neurinoma and 14 with hemifacial spasm. In 28 of the 368 patients, MR cisternograms depicted an acoustic neurinoma that was confirmed on postcontrast T1-weighted images. Meanwhile, in five of the 14 patients with hemifacial spasm, MR cisternograms revealed a vessel compressing the root exit zone of the affected facial nerve. It is concluded that MR cisternography using three-dimensional half-Fourier single-shot fast spin-echo sequences can be a useful means for demonstrating nerves within the auditory nerve as well as for the screening of acoustic neurionoma. (author)

Self-Consistent Theory of Shot Noise Suppression in Ballistic Conductors

Science.gov (United States)

Bulashenko, O. M.; Rubí, J. M.; Kochelap, V. A.

Shot-noise measurements become a fundamental tool to probe carrier interactions in mesoscopic systems [1]. A matter of particular interest is the significance of Coulomb interaction which may keep nearby electrons more regularly spaced rather than strictly at random and lead to the noise reduction. That effect occurs in different physical situations. Among them are charge-limited ballistic transport, resonant tunneling, single-electron tunneling, etc. In this communication we address the problem of Coulomb correlations in ballistic conductors under the space-charge-limited transport conditions, and present for the first time a semiclassical self-consistent theory of shot noise in these conductors by solving analytically the kinetic equation coupled self-consistently with a Poisson equation. Basing upon this theory, exact results for current noise in a two-terminal ballistic conductor under the action of long-range Coulomb correlations has been derived. The noise reduction factor (in respect to the uncorrelated value) is obtained in a closed analytical form for a full range of biases ranging from thermal to shot-noise limits which describe perfectly the results of the Monte Carlo simulations for a nondegenerate electron gas [2]. The magnitude of the noise reduction exceeds 0.01, which is of interest from the point of view of possible applications. Using these analytical results one may estimate a relative contribution to the noise from different groups of carriers (in energy space and/or real space) and to investigate in great detail the correlations between different groups of carriers. This leads us to suggest an electron energy spectroscopy experiment to probe the Coulomb correlations in ballistic conductors. Indeed, while the injected carriers are uncorrelated, those in the volume of the conductor are strongly correlated, as follows from the derived formulas for the fluctuation of the distribution function. Those correlations may be observed experimentally by

Entrance, exit, and reentrance of one shot with a shotgun

DEFF Research Database (Denmark)

Gulmann, C; Hougen, H P

1999-01-01

The case being reported is one of a homicidal shotgun fatality with an unusual wound pattern. A 34-year-old man was shot at close range with a 12-gauge shotgun armed with No. 5 birdshot ammunition. The shot entered the left axillary region, exited through the left infraclavicular region, and ther......The case being reported is one of a homicidal shotgun fatality with an unusual wound pattern. A 34-year-old man was shot at close range with a 12-gauge shotgun armed with No. 5 birdshot ammunition. The shot entered the left axillary region, exited through the left infraclavicular region...

Effect of shot peening on metastable austenitic stainless steels

Energy Technology Data Exchange (ETDEWEB)

Fargas, G., E-mail: gemma.fargas@upc.edu [CIEFMA - Departament de Ciència dels Materials i Enginyeria Metallúrgica, Universitat Politècnica de Catalunya, 08028 Barcelona (Spain); CRnE, Centre de Recerca en Nanoenginyeria, Universitat Politècnica de Catalunya, 08028 Barcelona (Spain); Roa, J.J.; Mateo, A. [CIEFMA - Departament de Ciència dels Materials i Enginyeria Metallúrgica, Universitat Politècnica de Catalunya, 08028 Barcelona (Spain); CRnE, Centre de Recerca en Nanoenginyeria, Universitat Politècnica de Catalunya, 08028 Barcelona (Spain)

2015-08-12

In this work, shot peening was performed in a metastable austenitic stainless steel EN 1.4318 (AISI 301LN) in order to evaluate its effect on austenite to martensite phase transformation and also the influence on the fatigue limit. Two different steel conditions were considered: annealed, i.e., with a fully austenitic microstructure, and cold rolled, consisting of a mixture of austenite and martensite. X-ray diffraction, electron back-scattered diffraction and focus ion beam, as well as nanoindentation techniques, were used to elucidate deformation mechanisms activated during shot peening and correlate with fatigue response. Results pointed out that extensive plastic deformation and phase transformation developed in annealed specimens as a consequence of shot peening. However, the increase of roughness and the generation of microcracks led to a limited fatigue limit improvement. In contrast, shot peened cold rolled specimens exhibited enhanced fatigue limit. In the latter case, the main factor that determined the influence on the fatigue response was the distance from the injector, followed successively by the exit speed of the shots and the coverage factor.

Single-shot T1 mapping of the corpus callosum: A rapid characterization of fiber bundle anatomy

Directory of Open Access Journals (Sweden)

Sabine eHofer

2015-05-01

Full Text Available Using diffusion-tensor MRI and fiber tractography the topographic organization of the corpus callosum (CC has been described to comprise 5 segments with fibers projecting into prefrontal (I, premotor and supplementary motor (II, primary motor (III, and primary sensory areas (IV, as well as into parietal, temporal, and occipital cortical areas (V. In order to more rapidly characterize the underlying anatomy of these segments, this study used a novel single-shot T1 mapping method to quantitatively determine T1 relaxation times in the human CC. A region-of-interest analysis revealed a tendency for the lowest T1 relaxation times in the genu and the highest T1 relaxation times in the somatomotor region of the CC. This observation separates regions dominated by myelinated fibers with large diameters (somatomotor area from densely packed smaller axonal bundles (genu with less myelin. The results indicate that characteristic T1 relaxation times in callosal profiles provide an additional means to monitor differences in fiber anatomy, fiber density, and gray matter in respective neocortical areas. In conclusion, rapid T1 mapping allows for a characterization of the axonal architecture in an individual CC in less than 10 s. The approach emerges as a valuable means for studying neocortical brain anatomy with possible implications for the diagnosis of neurodegenerative processes.

Potential hazard to human health from exposure to fragments of lead bullets and shot in the tissues of game animals.

Science.gov (United States)

Pain, Deborah J; Cromie, Ruth L; Newth, Julia; Brown, Martin J; Crutcher, Eric; Hardman, Pippa; Hurst, Louise; Mateo, Rafael; Meharg, Andrew A; Moran, Annette C; Raab, Andrea; Taggart, Mark A; Green, Rhys E

2010-04-26

Lead is highly toxic to animals. Humans eating game killed using lead ammunition generally avoid swallowing shot or bullets and dietary lead exposure from this source has been considered low. Recent evidence illustrates that lead bullets fragment on impact, leaving small lead particles widely distributed in game tissues. Our paper asks whether lead gunshot pellets also fragment upon impact, and whether lead derived from spent gunshot and bullets in the tissues of game animals could pose a threat to human health. Wild-shot gamebirds (6 species) obtained in the UK were X-rayed to determine the number of shot and shot fragments present, and cooked using typical methods. Shot were then removed to simulate realistic practice before consumption, and lead concentrations determined. Data from the Veterinary Medicines Directorate Statutory Surveillance Programme documenting lead levels in raw tissues of wild gamebirds and deer, without shot being removed, are also presented. Gamebirds containing > or =5 shot had high tissue lead concentrations, but some with fewer or no shot also had high lead concentrations, confirming X-ray results indicating that small lead fragments remain in the flesh of birds even when the shot exits the body. A high proportion of samples from both surveys had lead concentrations exceeding the European Union Maximum Level of 100 ppb w.w. (0.1 mg kg(-1) w.w.) for meat from bovine animals, sheep, pigs and poultry (no level is set for game meat), some by several orders of magnitude. High, but feasible, levels of consumption of some species could result in the current FAO/WHO Provisional Weekly Tolerable Intake of lead being exceeded. The potential health hazard from lead ingested in the meat of game animals may be larger than previous risk assessments indicated, especially for vulnerable groups, such as children, and those consuming large amounts of game.

Potential Hazard to Human Health from Exposure to Fragments of Lead Bullets and Shot in the Tissues of Game Animals

Science.gov (United States)

Pain, Deborah J.; Cromie, Ruth L.; Newth, Julia; Brown, Martin J.; Crutcher, Eric; Hardman, Pippa; Hurst, Louise; Mateo, Rafael; Meharg, Andrew A.; Moran, Annette C.; Raab, Andrea; Taggart, Mark A.; Green, Rhys E.

2010-01-01

Background Lead is highly toxic to animals. Humans eating game killed using lead ammunition generally avoid swallowing shot or bullets and dietary lead exposure from this source has been considered low. Recent evidence illustrates that lead bullets fragment on impact, leaving small lead particles widely distributed in game tissues. Our paper asks whether lead gunshot pellets also fragment upon impact, and whether lead derived from spent gunshot and bullets in the tissues of game animals could pose a threat to human health. Methodology/Principal Findings Wild-shot gamebirds (6 species) obtained in the UK were X-rayed to determine the number of shot and shot fragments present, and cooked using typical methods. Shot were then removed to simulate realistic practice before consumption, and lead concentrations determined. Data from the Veterinary Medicines Directorate Statutory Surveillance Programme documenting lead levels in raw tissues of wild gamebirds and deer, without shot being removed, are also presented. Gamebirds containing ≥5 shot had high tissue lead concentrations, but some with fewer or no shot also had high lead concentrations, confirming X-ray results indicating that small lead fragments remain in the flesh of birds even when the shot exits the body. A high proportion of samples from both surveys had lead concentrations exceeding the European Union Maximum Level of 100 ppb w.w. (0.1 mg kg−1 w.w.) for meat from bovine animals, sheep, pigs and poultry (no level is set for game meat), some by several orders of magnitude. High, but feasible, levels of consumption of some species could result in the current FAO/WHO Provisional Weekly Tolerable Intake of lead being exceeded. Conclusions/Significance The potential health hazard from lead ingested in the meat of game animals may be larger than previous risk assessments indicated, especially for vulnerable groups, such as children, and those consuming large amounts of game. PMID:20436670

Kids Guide to Shots

Science.gov (United States)

... First Aid & Safety Doctors & Hospitals Videos Recipes for Kids Kids site Sitio para niños How the Body ... Safe Videos for Educators Search English Español A Kid's Guide to Shots KidsHealth / For Kids / A Kid's ...

Light field driven streak-camera for single-shot measurements of the temporal profile of XUV-pulses from a free-electron laser; Lichtfeld getriebene Streak-Kamera zur Einzelschuss Zeitstrukturmessung der XUV-Pulse eines Freie-Elektronen Lasers

Energy Technology Data Exchange (ETDEWEB)

Fruehling, Ulrike

2009-10-15

The Free Electron Laser in Hamburg (FLASH) is a source for highly intense ultra short extreme ultraviolet (XUV) light pulses with pulse durations of a few femtoseconds. Due to the stochastic nature of the light generation scheme based on self amplified spontaneous emission (SASE), the duration and temporal profile of the XUV pulses fluctuate from shot to shot. In this thesis, a THz-field driven streak-camera capable of single pulse measurements of the XUV pulse-profile has been realized. In a first XUV-THz pump-probe experiment at FLASH, the XUV-pulses are overlapped in a gas target with synchronized THz-pulses generated by a new THz-undulator. The electromagnetic field of the THz light accelerates photoelectrons produced by the XUV-pulses with the resulting change of the photoelectron momenta depending on the phase of the THz field at the time of ionisation. This technique is intensively used in attosecond metrology where near infrared streaking fields are employed for the temporal characterisation of attosecond XUV-Pulses. Here, it is adapted for the analysis of pulse durations in the few femtosecond range by choosing a hundred times longer far infrared streaking wavelengths. Thus, the gap between conventional streak cameras with typical resolutions of hundreds of femtoseconds and techniques with attosecond resolution is filled. Using the THz-streak camera, the time dependent electric field of the THz-pulses was sampled in great detail while on the other hand the duration and even details of the time structure of the XUV-pulses were characterized. (orig.)

Multi-photon absorption limits to heralded single photon sources

Science.gov (United States)

Husko, Chad A.; Clark, Alex S.; Collins, Matthew J.; De Rossi, Alfredo; Combrié, Sylvain; Lehoucq, Gaëlle; Rey, Isabella H.; Krauss, Thomas F.; Xiong, Chunle; Eggleton, Benjamin J.

2013-01-01

Single photons are of paramount importance to future quantum technologies, including quantum communication and computation. Nonlinear photonic devices using parametric processes offer a straightforward route to generating photons, however additional nonlinear processes may come into play and interfere with these sources. Here we analyse spontaneous four-wave mixing (SFWM) sources in the presence of multi-photon processes. We conduct experiments in silicon and gallium indium phosphide photonic crystal waveguides which display inherently different nonlinear absorption processes, namely two-photon (TPA) and three-photon absorption (ThPA), respectively. We develop a novel model capturing these diverse effects which is in excellent quantitative agreement with measurements of brightness, coincidence-to-accidental ratio (CAR) and second-order correlation function g(2)(0), showing that TPA imposes an intrinsic limit on heralded single photon sources. We build on these observations to devise a new metric, the quantum utility (QMU), enabling further optimisation of single photon sources. PMID:24186400

Numerical investigation of a shot peening process by a finite element approach

DEFF Research Database (Denmark)

Liu, Hongsheng; Zhang, Xiaodan; Hansen, Niels

2014-01-01

Shot peening is a surface impact treatment widely used to improve the performance of a metal or a component. The better performance of the shot peened part is controlled by compressive residual stresses resulting from the plastic deformation of the surface layers by impacts of shot. The compressive...... residual stress is generally measured by X-ray diffraction. However, considerable cost and time are needed for such measurements. For this reason, in this work a 3D finite element (FE) model is introduced for a shot peening process. Through the FE simulations, the effect of process parameters...... such as damping ratio of material, friction coefficient, shot velocity and shot angle on the magnitude and distribution of the compressive residual stress is examined....

Single-Photon Source for Quantum Information Based on Single Dye Molecule Fluorescence in Liquid Crystal Host

International Nuclear Information System (INIS)

Lukishova, S.G.; Knox, R.P.; Freivald, P.; McNamara, A.; Boyd, R.W.; Stroud, Jr. C.R.; Schmid, A.W.; Marshall, K.L.

2006-01-01

This paper describes a new application for liquid crystals: quantum information technology. A deterministically polarized single-photon source that efficiently produces photons exhibiting antibunching is a pivotal hardware element in absolutely secure quantum communication. Planar-aligned nematic liquid crystal hosts deterministically align the single dye molecules which produce deterministically polarized single (antibunched) photons. In addition, 1-D photonic bandgap cholesteric liquid crystals will increase single-photon source efficiency. The experiments and challenges in the observation of deterministically polarized fluorescence from single dye molecules in planar-aligned glassy nematic-liquid-crystal oligomer as well as photon antibunching in glassy cholesteric oligomer are described for the first time

Deterministic and Storable Single-Photon Source Based on a Quantum Memory

International Nuclear Information System (INIS)

Chen Shuai; Chen, Y.-A.; Strassel, Thorsten; Zhao Bo; Yuan Zhensheng; Pan Jianwei; Schmiedmayer, Joerg

2006-01-01

A single-photon source is realized with a cold atomic ensemble ( 87 Rb atoms). A single excitation, written in an atomic quantum memory by Raman scattering of a laser pulse, is retrieved deterministically as a single photon at a predetermined time. It is shown that the production rate of single photons can be enhanced considerably by a feedback circuit while the single-photon quality is conserved. Such a single-photon source is well suited for future large-scale realization of quantum communication and linear optical quantum computation

Deep-blue supercontinuum light sources based on tapered photonic crystal bres

DEFF Research Database (Denmark)

Sørensen, Simon Toft

applications in areas such as spectroscopy and microscopy. In this work, we exploit the tremendous design freedom in air hole structured photonic crystal fibres to shape the supercontinuum spectrum. Specifically, the supercontinuum dynamics can be controlled by clever engineering of fibres with longitudinally...... varying air hole structures. Here we demonstrate supercontinuum generation into the commercially attractive deep-blue spectral region below 400 nm from an Yb laser in such fibres. In particular, we introduce the concept of a group acceleration mismatch that allows us to enhance the amount of light...... in the deep-blue by optimising the fibre structure. To this end, we fabricate the first single-mode high air-fill fraction photonic crystal fibre for blue-extended supercontinuum sources. The mechanisms of supercontinuum broadening are highly sensitive to noise, and the inherent shot-to-shot variations...

Partial differential equation-based localization of a monopole source from a circular array.

Science.gov (United States)

Ando, Shigeru; Nara, Takaaki; Levy, Tsukassa

2013-10-01

Wave source localization from a sensor array has long been the most active research topics in both theory and application. In this paper, an explicit and time-domain inversion method for the direction and distance of a monopole source from a circular array is proposed. The approach is based on a mathematical technique, the weighted integral method, for signal/source parameter estimation. It begins with an exact form of the source-constraint partial differential equation that describes the unilateral propagation of wide-band waves from a single source, and leads to exact algebraic equations that include circular Fourier coefficients (phase mode measurements) as their coefficients. From them, nearly closed-form, single-shot and multishot algorithms are obtained that is suitable for use with band-pass/differential filter banks. Numerical evaluation and several experimental results obtained using a 16-element circular microphone array are presented to verify the validity of the proposed method.

SunShot Vision Study: February 2012 (Book)

Energy Technology Data Exchange (ETDEWEB)

2012-02-01

The objective of the SunShot Vision Study is to provide an in-depth assessment of the potential for solar technologies to meet a significant share of electricity demand in the United States during the next several decades. Specifically, it explores a future in which the price of solar technologies declines by about 75% between 2010 and 2020 - in line with the U.S. Department of Energy (DOE) SunShot Initiative's targets.

Improvement of Surface Layer Characteristics by Shot Lining

Science.gov (United States)

Harada, Yasunori

In the present study, lining of the metal with foils using shot peening was investigated to improve the surface layer characteristics. In the shot peening experiment, the foils set on the metal are pelted with hard particles traveling at a high velocity. The foils are bonded to the metal surface due to plastic deformation induced by the collision of the particles. The foils and the metal are heated to heighten the bondability because of the reduction of flow stress. Lining the metal with the hard powder sandwiched between two aluminum foil sheets was also attempted. In this experiment, a centrifugal shot peening machine wite an electrical heater was employed. The metals are commercially aluminium alloys and magnesium alloys, and the foils are commercially aluminum, titanium and nickel. The effects of shot speed and the heating temperature on the bondability were examined. Wear resistance was also evaluated by grinding. The foils were successfully bonded to the metal surface. It was found that the present method is effective in improving of surface layer characteristics.

Feasibility study of broadband efficient ''water window'' source

Energy Technology Data Exchange (ETDEWEB)

Higashiguchi, Takeshi; Yugami, Noboru [Department of Advanced Interdisciplinary Sciences, Center for Optical Research and Education (CORE), and Optical Technology Innovation Center (OpTIC), Utsunomiya University, Yoto 7-1-2, Utsunomiya, Tochigi 321-8585 (Japan); Japan Science and Technology Agency, CREST, 4-1-8 Honcho, Kanagawa, Saitama 332-0012 (Japan); Otsuka, Takamitsu [Department of Advanced Interdisciplinary Sciences, Center for Optical Research and Education (CORE), and Optical Technology Innovation Center (OpTIC), Utsunomiya University, Yoto 7-1-2, Utsunomiya, Tochigi 321-8585 (Japan); Jiang Weihua [Department of Electrical Engineering, Nagaoka University of Technology, Kami-tomiokamachi 1603-1, Nagaoka, Niigata 940-2188 (Japan); Endo, Akira [Research Institute for Science and Engineering, Waseda University, Okubo 3-4-1, Shinjuku, Tokyo 169-8555 (Japan); Li Bowen; Dunne, Padraig; O' Sullivan, Gerry [School of Physics, University College Dublin, Belfield, Dublin 4 (Ireland)

2012-01-02

We demonstrate a table-top broadband emission water window source based on laser-produced high-Z plasmas. Resonance emission from multiply charged ions merges to produce intense unresolved transition arrays (UTAs) in the 2-4 nm region, extending below the carbon K edge (4.37 nm). Arrays resulting from n=4-n=4 transitions are overlaid with n=4-n=5 emission and shift to shorter wavelength with increasing atomic number. An outline of a microscope design for single-shot live cell imaging is proposed based on a bismuth plasma UTA source, coupled to multilayer mirror optics.

Get Your Flu Shot!| NIH MedlinePlus the Magazine

Science.gov (United States)

... of this page please turn Javascript on. Feature: Flu Shot Get Your Flu Shot! Past Issues / Winter 2011 Table of Contents ... failure, or lung disease "For the 2010–2011 flu season, the flu vaccine provides protection against the ...

Neutron generator tube ion source control apparatus

International Nuclear Information System (INIS)

Bridges, J.R.

1982-01-01

A pulsed neutron well logging system includes a neutron generator tube of the deuterium-tritium accelerator type and an ion source control apparatus providing extremely sharply time-defined neutron pulses. A low voltage control pulse supplied to an input by timing circuits turns a power FET on via a buffer-driver whereby a 2000 volt pulse is produced in the secondary of a pulse transformer and applied to the ion source of the tube. A rapid fall in this ion source control pulse is ensured by a quenching circuit wherein a one-shot responds to the falling edge of the control pulse and produces a 3 microsecond delay to compensate for the propagation delay. A second one-shot is triggered by the falling edge of the output of the first one-shot and gives an 8 microsecond pulse to turn on the power FET which, via an isolation transformer turns on a series-connected transistor to ground the secondary of the pulse transformer and the ion source. (author)

The Effect of Multiple Shot Peening on the Corrosion Behavior of Duplex Stainless Steel

Science.gov (United States)

Feng, Qiang; She, Jia; Wu, Xueyan; Wang, Chengxi; Jiang, Chuanhai

2018-03-01

Various types of shot peening treatments were applied to duplex stainless steel. The effects of shot peening intensity and working procedures on the microstructure were investigated. The domain size and microstrain evolution in the surface layer were characterized utilizing the Rietveld method. As the shot peening intensity increased, the surface roughness increased in the surface layer; however, it decreased after multiple (dual and triple) shot peening. The mole fraction of strain-induced martensite as a function of the intensity of shot peening was evaluated by XRD measurements. Both potentiodynamic polarization curves and salt spray tests of shot-peened samples in NaCl solution were investigated. The results indicate that traditional shot peening has negative effects on corrosion resistance with increasing shot peening intensity; however, the corrosion rate can be reduced by means of multiple shot peening.

Flu shots and the characteristics of unvaccinated elderly Medicare beneficiaries.

Science.gov (United States)

Lochner, Kimberly A; Wynne, Marc

2011-12-21

Data from the Medicare Current Beneficiary Survey, 2009. • Overall, 73% of Medicare beneficiaries aged 65 years and older reported receiving a flu shot for the 2008 flu season, but vaccination rates varied by socio-demographic characteristics. Flu vaccination was lowest for beneficiaries aged 65-74 years old, who were non-Hispanic Blacks and Hispanics, were not married, had less than a high school education, or who were eligible for Medicaid (i.e., dual eligibles). • Healthcare utilization and personal health behavior were also related to vaccination rates, with current smokers and those with no hospitalizations or physician visits being less likely to be vaccinated. • Among those beneficiaries who reported receiving a flu shot, 59% received it in a physician's office or clinic, with the next most common setting being in the community (21%); e.g., grocery store, shopping mall, library, or church. • Among those beneficiaries who did not receive a flu shot, the most common reasons were beliefs that the shot could cause side effects or disease (20%), that they didn't think the shot could prevent the flu (17%), or that the shot wasn't needed (16%). Less than 1% reported that they didn't get the flu shot because of cost. Elderly persons (aged 65 years and older) are at increased risk of complications from influenza, with the majority of influenza-related hospitalizations and deaths occurring among the elderly (Fiore et al., 2010). Most physicians recommend their elderly patients get a flu shot each year, and many hospitals inquire about elderly patient's immunization status upon admission, providing a vaccination if requested. The importance of getting a flu shot is underscored by the Department of Health and Human Services' Healthy People initiative, which has set a vaccination goal of 90% for the Nation's elderly by the year 2020 (Department of Health and Human Services [DHHS], 2011). Although all costs related to flu shots are covered by Medicare, requiring

Unsupervised Video Shot Detection Using Clustering Ensemble with a Color Global Scale-Invariant Feature Transform Descriptor

Directory of Open Access Journals (Sweden)

Yuchou Chang

2008-02-01

Full Text Available Scale-invariant feature transform (SIFT transforms a grayscale image into scale-invariant coordinates of local features that are invariant to image scale, rotation, and changing viewpoints. Because of its scale-invariant properties, SIFT has been successfully used for object recognition and content-based image retrieval. The biggest drawback of SIFT is that it uses only grayscale information and misses important visual information regarding color. In this paper, we present the development of a novel color feature extraction algorithm that addresses this problem, and we also propose a new clustering strategy using clustering ensembles for video shot detection. Based on Fibonacci lattice-quantization, we develop a novel color global scale-invariant feature transform (CGSIFT for better description of color contents in video frames for video shot detection. CGSIFT first quantizes a color image, representing it with a small number of color indices, and then uses SIFT to extract features from the quantized color index image. We also develop a new space description method using small image regions to represent global color features as the second step of CGSIFT. Clustering ensembles focusing on knowledge reuse are then applied to obtain better clustering results than using single clustering methods for video shot detection. Evaluation of the proposed feature extraction algorithm and the new clustering strategy using clustering ensembles reveals very promising results for video shot detection.

Unsupervised Video Shot Detection Using Clustering Ensemble with a Color Global Scale-Invariant Feature Transform Descriptor

Directory of Open Access Journals (Sweden)

Hong Yi

2008-01-01

Full Text Available Abstract Scale-invariant feature transform (SIFT transforms a grayscale image into scale-invariant coordinates of local features that are invariant to image scale, rotation, and changing viewpoints. Because of its scale-invariant properties, SIFT has been successfully used for object recognition and content-based image retrieval. The biggest drawback of SIFT is that it uses only grayscale information and misses important visual information regarding color. In this paper, we present the development of a novel color feature extraction algorithm that addresses this problem, and we also propose a new clustering strategy using clustering ensembles for video shot detection. Based on Fibonacci lattice-quantization, we develop a novel color global scale-invariant feature transform (CGSIFT for better description of color contents in video frames for video shot detection. CGSIFT first quantizes a color image, representing it with a small number of color indices, and then uses SIFT to extract features from the quantized color index image. We also develop a new space description method using small image regions to represent global color features as the second step of CGSIFT. Clustering ensembles focusing on knowledge reuse are then applied to obtain better clustering results than using single clustering methods for video shot detection. Evaluation of the proposed feature extraction algorithm and the new clustering strategy using clustering ensembles reveals very promising results for video shot detection.

Single-source gamma radiation procedures for improved calibration and measurements in porous media

International Nuclear Information System (INIS)

Oostrom, M.; Hofstee, C.; Dane, H.; Lenhard, R.J.

1998-01-01

When dual-energy gamma radiation systems are employed for measurements in porous media, count rates from both sources are often used to compute parameter values. However, for several applications, the count rates of just one source are insufficient. These applications include the determination of volumetric liquid content values in two-liquid systems and salt concentration values in water-saturated porous media. Single-energy gamma radiation procedures for three applications are described in this paper. Through an error analysis, single-source procedures are shown to reduce the probable error in the determinations considerably. Example calculations and simple column experiments were conducted for each application to compare the performance of the new single-source and standard dual-source methods. In all cases, the single-source methods provided more reliable data than the traditional dual-source methods. In addition, a single-source calibration procedure is proposed to determine incident count rates indirectly. This procedure, which requires packing under saturated conditions, can be used in all single- and dual-source applications and yields accurate porosity and dry bulk density values

Mumps and the Vaccine (Shot) to Prevent It

Science.gov (United States)

... as measles and rubella. Prevents your child from getting a fever and swollen glands under the ears or jaw from mumps. Keeps your child from missing school or child care (and keeps you from missing work to care for your sick child). Is the MMR shot safe? Yes. The MMR shot is very safe, and it ...

Kinematic Differences between Set- and Jump-Shot Motions in Basketball

Directory of Open Access Journals (Sweden)

Hiroki Okubo

2018-02-01

Full Text Available Shooting arm motions at release in one-hand set and jump basketball shots have been analyzed using a kinematic model. Set and jump shots are classified by the vertical velocity and acceleration of the shooter’s shooting-side shoulder at release. The two-dimensional three-segment model includes the vertical shooting-side shoulder velocity and acceleration. Numerical simulation investigates the effect of shoulder motion. Release backspin angular velocity can be described as a function of the vertical shoulder acceleration and the vertical fingertip acceleration relative to the shoulder. For proper backspin, jump shots require large vertical fingertip acceleration relative to the shoulder. The upward shoulder speed at release contributes to the vertical fingertip velocity relative to the shoulder for a given desired ball release speed, angle and backspin. On the other hand, upward shoulder motion does not contribute to the horizontal direction. As horizontal shot distance increases, upper arm angular speed also increases to produce the ball release conditions. Ball release with upward shoulder speed reduces the magnitudes of the upper arm, forearm and hand angular velocities. All these facts imply that the shooting arm motion in the jump shot is different from that of the set shot.

A shot parameter specification subsystem for automated control of PBFA II accelerator shots

International Nuclear Information System (INIS)

Spiller, J.L.

1987-01-01

The author reports on the shot parameter specification subsystem (SPSS), an integral part of the automatic control system developed for the Particle Beam Fusion Accelerator II (PBFA II). This system has been designed to fully utilize the accelerator by tailoring shot parameters to the needs of the experimenters. The SPSS is the key to this flexibility. Automatic systems will be required on many pulsed power machines for the fastest turnaround, the highest reliability, and most cost effective operation. These systems will require the flexibility and the ease of use that is part of the SPSS. The author discusses how the PBFA II control system has proved to be an effective modular system, flexible enough to meet the demands of both the fast track construction of PBFA II and the control needs of Hermes III. This system is expected to meet the demands of most future machine changes

The reliability and internal consistency of one-shot and flicker change detection for measuring individual differences in visual working memory capacity.

Science.gov (United States)

Pailian, Hrag; Halberda, Justin

2015-04-01

We investigated the psychometric properties of the one-shot change detection task for estimating visual working memory (VWM) storage capacity-and also introduced and tested an alternative flicker change detection task for estimating these limits. In three experiments, we found that the one-shot whole-display task returns estimates of VWM storage capacity (K) that are unreliable across set sizes-suggesting that the whole-display task is measuring different things at different set sizes. In two additional experiments, we found that the one-shot single-probe variant shows improvements in the reliability and consistency of K estimates. In another additional experiment, we found that a one-shot whole-display-with-click task (requiring target localization) also showed improvements in reliability and consistency. The latter results suggest that the one-shot task can return reliable and consistent estimates of VWM storage capacity (K), and they highlight the possibility that the requirement to localize the changed target is what engenders this enhancement. Through a final series of four experiments, we introduced and tested an alternative flicker change detection method that also requires the observer to localize the changing target and that generates, from response times, an estimate of VWM storage capacity (K). We found that estimates of K from the flicker task correlated with estimates from the traditional one-shot task and also had high reliability and consistency. We highlight the flicker method's ability to estimate executive functions as well as VWM storage capacity, and discuss the potential for measuring multiple abilities with the one-shot and flicker tasks.

An investigation of the properties of conventional and severe shot peened low alloy steel

Science.gov (United States)

Quang Trung, Pham; Butler, David Lee; Win Khun, Nay

2017-07-01

The effects of the conventional shot peening and severe shot peening process on the mechanical and tribological properties of shot peened AISI 4340 high strength steel were systematically investigated. Compared with the conventional shot peened sample, the ultrafine grain surface layer with a depth of about 20 µm generated by the severe shot peening process can enhance the hardness and wear resistance of the treated material. However, deeper dimples generated by the high media velocity in the severe shot peening process resulted in a higher surface roughness, which is considered as a side effect of this method reducing the fatigue life of the material. Applying a smaller shot size with an appropriate intensity can be used to peen the severe shot peened samples to not only reduce the surface roughness and friction coefficient but also improve the wear resistance for these samples. This work was presented in the shot peening section during ‘The 30th International Conference on Surface Modification Technologies, 2016, Milan, Italy’ (SMT30, ID 61, entitled ‘Comparison of the effects of conventional shot peening and severe shot peening processes on the mechanical and tribological properties of shot peened AISI 4340’) and the authors were encouraged to submit a manuscript to the Materials Research Express journal after adding some nessesary information.

Laser-produced multi-charged heavy ions as efficient soft x-ray sources

International Nuclear Information System (INIS)

Higashiguchi, Takeshi; Suzuki, Yuhei; Kawasaki, Masato

2016-01-01

We demonstrate EUV and soft x-ray sources in the 2 to 7 nm spectral region related to the beyond EUV (BEUV) question at 6x nm and a water window source based on laser-produced high-Z plasmas. Resonance emission from multiply charged ions merges to produce intense unresolved transition arrays (UTAs), extending below the carbon K edge (4.37 nm). An outline of a microscope design for single-shot live cell imaging is proposed based on a high-Z plasma UTA source, coupled to x-ray optics. We will discuss the progress and Z-scaling of UTA emission spectra to achieve lab-scale table-top, efficient, high-brightness high-Z plasma EUV-soft x-ray sources for in vivo bio-imaging applications. (author)

Single Photon Sources in Silicon Carbide

International Nuclear Information System (INIS)

Brett Johnson

2014-01-01

Single photon sources in semiconductors are highly sought after as they constitute the building blocks of a diverse range of emerging technologies such as integrated quantum information processing, quantum metrology and quantum photonics. In this presentation, we show the first observation of single photon emission from deep level defects in silicon carbide (SiC). The single photon emission is photo-stable at room temperature and surprisingly bright. This represents an exciting alternative to diamond color centers since SiC possesses well-established growth and device engineering protocols. The defect is assigned to the carbon vacancy-antisite pair which gives rise to the AB photoluminescence lines. We discuss its photo-physical properties and their fabrication via electron irradiation. Preliminary measurements on 3C SiC nano-structures will also be discussed. (author)

Potential hazard to human health from exposure to fragments of lead bullets and shot in the tissues of game animals.

Directory of Open Access Journals (Sweden)

Deborah J Pain

Full Text Available BACKGROUND: Lead is highly toxic to animals. Humans eating game killed using lead ammunition generally avoid swallowing shot or bullets and dietary lead exposure from this source has been considered low. Recent evidence illustrates that lead bullets fragment on impact, leaving small lead particles widely distributed in game tissues. Our paper asks whether lead gunshot pellets also fragment upon impact, and whether lead derived from spent gunshot and bullets in the tissues of game animals could pose a threat to human health. METHODOLOGY/PRINCIPAL FINDINGS: Wild-shot gamebirds (6 species obtained in the UK were X-rayed to determine the number of shot and shot fragments present, and cooked using typical methods. Shot were then removed to simulate realistic practice before consumption, and lead concentrations determined. Data from the Veterinary Medicines Directorate Statutory Surveillance Programme documenting lead levels in raw tissues of wild gamebirds and deer, without shot being removed, are also presented. Gamebirds containing > or =5 shot had high tissue lead concentrations, but some with fewer or no shot also had high lead concentrations, confirming X-ray results indicating that small lead fragments remain in the flesh of birds even when the shot exits the body. A high proportion of samples from both surveys had lead concentrations exceeding the European Union Maximum Level of 100 ppb w.w. (0.1 mg kg(-1 w.w. for meat from bovine animals, sheep, pigs and poultry (no level is set for game meat, some by several orders of magnitude. High, but feasible, levels of consumption of some species could result in the current FAO/WHO Provisional Weekly Tolerable Intake of lead being exceeded. CONCLUSIONS/SIGNIFICANCE: The potential health hazard from lead ingested in the meat of game animals may be larger than previous risk assessments indicated, especially for vulnerable groups, such as children, and those consuming large amounts of game.

Single-shot echo-planar MR sequences in the diagnosis of intracranial infectious diseases

International Nuclear Information System (INIS)

Tsuchiya, Kazuhiro; Katase, Shichiro; Yoshino, Ayako; Yamakami, Norio; Hachiya, Junichi

1998-01-01

The purpose of this study was to present our preliminary experience in the application of echo-planar-imaging (EPI) MR sequences for the diagnosis of intracranial infectious diseases and to assess the value of these sequences. We reviewed single-shot EPI MR images obtained at 1.5 T in 17 patients and compared these images with conventional or fast spin-echo (SE) or fluid attenuated inversion-recovery (FLAIR) images. The clinical diagnoses for the 17 patients were meningitis (2 patients), encephalitis or meningoencephalitis (7 patients), brain abscess (5 patients), epidural empyema (2 patients) and Creutzfeldt-Jakob disease (1 patient). We obtained EPI-T 2 -weighted (T 2 W) images in 8 patients, EPI-FLAIR images in 13 patients and EPI-diffusion-weighted (DW) images in 14 patients. Among the 8 patients for whom EPI-T 2 W imaging was performed, EPI-T 2 W imaging yielded superior results compared with SE-T 2 W imaging in 3 patients as a consequence of patient motion and equal results compared with SE-T 2 W imaging in 5 patients. Among the 13 patients for whom EPI-FLAIR imaging was performed, the EPI-FLAIR images were superior to conventional FLAIR images in 3 unstable patients. In the remaining 10 patients for whom EPI-FLAIR imaging was performed, EPI-FLAIR images were equivalent or inferior to conventional FLAIR images. In 6 patients with encephalitis or meningoencephalitis, the encephalitic lesions showed hyperintensity in EPI-DW images to a greater extent than in images obtained with the other techniques. In 3 patients, EPI-DW images also demonstrated hyperintensity for the contents of abscesses or areas of empyema that was not seen with the other imaging techniques. The value of EPI-T 2 W and EPI-FLAIR imaging is limited in uncooperative patients. EPI-DW imaging was found to be of value for the evaluation of several intracranial infectious diseases. (author)

Single-shot echo-planar MR sequences in the diagnosis of intracranial infectious diseases

Energy Technology Data Exchange (ETDEWEB)

Tsuchiya, Kazuhiro; Katase, Shichiro; Yoshino, Ayako; Yamakami, Norio; Hachiya, Junichi [Kyorin Univ., Mitaka, Tokyo (Japan). School of Medicine

1998-06-01

The purpose of this study was to present our preliminary experience in the application of echo-planar-imaging (EPI) MR sequences for the diagnosis of intracranial infectious diseases and to assess the value of these sequences. We reviewed single-shot EPI MR images obtained at 1.5 T in 17 patients and compared these images with conventional or fast spin-echo (SE) or fluid attenuated inversion-recovery (FLAIR) images. The clinical diagnoses for the 17 patients were meningitis (2 patients), encephalitis or meningoencephalitis (7 patients), brain abscess (5 patients), epidural empyema (2 patients) and Creutzfeldt-Jakob disease (1 patient). We obtained EPI-T{sub 2}-weighted (T{sub 2}W) images in 8 patients, EPI-FLAIR images in 13 patients and EPI-diffusion-weighted (DW) images in 14 patients. Among the 8 patients for whom EPI-T{sub 2}W imaging was performed, EPI-T{sub 2}W imaging yielded superior results compared with SE-T{sub 2}W imaging in 3 patients as a consequence of patient motion and equal results compared with SE-T{sub 2}W imaging in 5 patients. Among the 13 patients for whom EPI-FLAIR imaging was performed, the EPI-FLAIR images were superior to conventional FLAIR images in 3 unstable patients. In the remaining 10 patients for whom EPI-FLAIR imaging was performed, EPI-FLAIR images were equivalent or inferior to conventional FLAIR images. In 6 patients with encephalitis or meningoencephalitis, the encephalitic lesions showed hyperintensity in EPI-DW images to a greater extent than in images obtained with the other techniques. In 3 patients, EPI-DW images also demonstrated hyperintensity for the contents of abscesses or areas of empyema that was not seen with the other imaging techniques. The value of EPI-T{sub 2}W and EPI-FLAIR imaging is limited in uncooperative patients. EPI-DW imaging was found to be of value for the evaluation of several intracranial infectious diseases. (author)

Energy Harvesting Research: The Road from Single Source to Multisource.

Science.gov (United States)

Bai, Yang; Jantunen, Heli; Juuti, Jari

2018-06-07

Energy harvesting technology may be considered an ultimate solution to replace batteries and provide a long-term power supply for wireless sensor networks. Looking back into its research history, individual energy harvesters for the conversion of single energy sources into electricity are developed first, followed by hybrid counterparts designed for use with multiple energy sources. Very recently, the concept of a truly multisource energy harvester built from only a single piece of material as the energy conversion component is proposed. This review, from the aspect of materials and device configurations, explains in detail a wide scope to give an overview of energy harvesting research. It covers single-source devices including solar, thermal, kinetic and other types of energy harvesters, hybrid energy harvesting configurations for both single and multiple energy sources and single material, and multisource energy harvesters. It also includes the energy conversion principles of photovoltaic, electromagnetic, piezoelectric, triboelectric, electrostatic, electrostrictive, thermoelectric, pyroelectric, magnetostrictive, and dielectric devices. This is one of the most comprehensive reviews conducted to date, focusing on the entire energy harvesting research scene and providing a guide to seeking deeper and more specific research references and resources from every corner of the scientific community. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Shot loading platform analysis

International Nuclear Information System (INIS)

Norman, B.F.

1994-01-01

This document provides the wind/seismic analysis and evaluation for the shot loading platform. Hand calculations were used for the analysis. AISC and UBC load factors were used in this evaluation. The results show that the actual loads are under the allowable loads and all requirements are met

Maximum one-shot dissipated work from Rényi divergences

Science.gov (United States)

Yunger Halpern, Nicole; Garner, Andrew J. P.; Dahlsten, Oscar C. O.; Vedral, Vlatko

2018-05-01

Thermodynamics describes large-scale, slowly evolving systems. Two modern approaches generalize thermodynamics: fluctuation theorems, which concern finite-time nonequilibrium processes, and one-shot statistical mechanics, which concerns small scales and finite numbers of trials. Combining these approaches, we calculate a one-shot analog of the average dissipated work defined in fluctuation contexts: the cost of performing a protocol in finite time instead of quasistatically. The average dissipated work has been shown to be proportional to a relative entropy between phase-space densities, to a relative entropy between quantum states, and to a relative entropy between probability distributions over possible values of work. We derive one-shot analogs of all three equations, demonstrating that the order-infinity Rényi divergence is proportional to the maximum possible dissipated work in each case. These one-shot analogs of fluctuation-theorem results contribute to the unification of these two toolkits for small-scale, nonequilibrium statistical physics.

EUV sources for the alpha-tools

Science.gov (United States)

Pankert, Joseph; Apetz, Rolf; Bergmann, Klaus; Damen, Marcel; Derra, Günther; Franken, Oliver; Janssen, Maurice; Jonkers, Jeroen; Klein, Jürgen; Kraus, Helmar; Krücken, Thomas; List, Andreas; Loeken, Micheal; Mader, Arnaud; Metzmacher, Christof; Neff, Willi; Probst, Sven; Prümmer, Ralph; Rosier, Oliver; Schwabe, Stefan; Seiwert, Stefan; Siemons, Guido; Vaudrevange, Dominik; Wagemann, Dirk; Weber, Achim; Zink, Peter; Zitzen, Oliver

2006-03-01

In this paper, we report on the recent progress of the Philips Extreme UV source. The Philips source concept is based on a discharge plasma ignited in a Sn vapor plume that is ablated by a laser pulse. Using rotating electrodes covered with a regenerating tin surface, the problems of electrode erosion and power scaling are fundamentally solved. Most of the work of the past year has been dedicated to develop a lamp system which is operating very reliably and stable under full scanner remote control. Topics addressed were the development of the scanner interface, a dose control system, thermo-mechanical design, positional stability of the source, tin handling, and many more. The resulting EUV source-the Philips NovaTin(R) source-can operate at more than 10kW electrical input power and delivers 200W in-band EUV into 2π continuously. The source is very small, so nearly 100% of the EUV radiation can be collected within etendue limits. The lamp system is fully automated and can operate unattended under full scanner remote control. 500 Million shots of continuous operation without interruption have been realized, electrode lifetime is at least 2 Billion shots. Three sources are currently being prepared, two of them will be integrated into the first EUV Alpha Demonstration tools of ASML. The debris problem was reduced to a level which is well acceptable for scanner operation. First, a considerable reduction of the Sn emission of the source has been realized. The debris mitigation system is based on a two-step concept using a foil trap based stage and a chemical cleaning stage. Both steps were improved considerably. A collector lifetime of 1 Billion shots is achieved, after this operating time a cleaning would be applied. The cleaning step has been verified to work with tolerable Sn residues. From the experimental results, a total collector lifetime of more than 10 Billion shots can be expected.

Single-shot T2 mapping using overlapping-echo detachment planar imaging and a deep convolutional neural network.

Science.gov (United States)

Cai, Congbo; Wang, Chao; Zeng, Yiqing; Cai, Shuhui; Liang, Dong; Wu, Yawen; Chen, Zhong; Ding, Xinghao; Zhong, Jianhui

2018-04-24

An end-to-end deep convolutional neural network (CNN) based on deep residual network (ResNet) was proposed to efficiently reconstruct reliable T 2 mapping from single-shot overlapping-echo detachment (OLED) planar imaging. The training dataset was obtained from simulations that were carried out on SPROM (Simulation with PRoduct Operator Matrix) software developed by our group. The relationship between the original OLED image containing two echo signals and the corresponding T 2 mapping was learned by ResNet training. After the ResNet was trained, it was applied to reconstruct the T 2 mapping from simulation and in vivo human brain data. Although the ResNet was trained entirely on simulated data, the trained network was generalized well to real human brain data. The results from simulation and in vivo human brain experiments show that the proposed method significantly outperforms the echo-detachment-based method. Reliable T 2 mapping with higher accuracy is achieved within 30 ms after the network has been trained, while the echo-detachment-based OLED reconstruction method took approximately 2 min. The proposed method will facilitate real-time dynamic and quantitative MR imaging via OLED sequence, and deep convolutional neural network has the potential to reconstruct maps from complex MRI sequences efficiently. © 2018 International Society for Magnetic Resonance in Medicine.

SU-F-P-36: Automation of Linear Accelerator Star Shot Measurement with Advanced XML Scripting and Electronic Portal Imaging Device

International Nuclear Information System (INIS)

Nguyen, N; Knutson, N; Schmidt, M; Price, M

2016-01-01

Purpose: To verify a method used to automatically acquire jaw, MLC, collimator and couch star shots for a Varian TrueBeam linear accelerator utilizing Developer Mode and an Electronic Portal Imaging Device (EPID). Methods: An XML script was written to automate motion of the jaws, MLC, collimator and couch in TrueBeam Developer Mode (TBDM) to acquire star shot measurements. The XML script also dictates MV imaging parameters to facilitate automatic acquisition and recording of integrated EPID images. Since couch star shot measurements cannot be acquired using a combination of EPID and jaw/MLC collimation alone due to a fixed imager geometry, a method utilizing a 5mm wide steel ruler placed on the table and centered within a 15×15cm2 open field to produce a surrogate of the narrow field aperture was investigated. Four individual star shot measurements (X jaw, Y jaw, MLC and couch) were obtained using our proposed as well as traditional film-based method. Integrated EPID images and scanned measurement films were analyzed and compared. Results: Star shot (X jaw, Y jaw, MLC and couch) measurements were obtained in a single 5 minute delivery using the TBDM XML script method compared to 60 minutes for equivalent traditional film measurements. Analysis of the images and films demonstrated comparable isocentricity results, agreeing within 0.3mm of each other. Conclusion: The presented automatic approach of acquiring star shot measurements using TBDM and EPID has proven to be more efficient than the traditional film approach with equivalent results.

Mug shot exposure prior to lineup identification: interference, transference, and commitment effects.

Science.gov (United States)

Dysart, J E; Lindsay, R C; Hammond, R; Dupuis, P

2001-12-01

The effects of viewing mug shots on subsequent identification performance are as yet unclear. Two experiments used a live staged-crime paradigm to determine if interpolated eyewitness exposure to mug shots caused interference, unconscious transference, or commitment effects influencing subsequent lineup accuracy. Experiment 1 (N = 104) tested interference effects. Similar correct decision rates were obtained for the mug shot and no mug shot groups from both perpetrator-present and absent lineups. Experiment 2 (N = 132) tested for commitment and transference effects. Results showed that the commitment group made significantly more incorrect identifications than either the control or the transference group, which had similar false-identification rates. Commitment effects present a serious threat to identification accuracy from lineups following mug shot searches.

Acceptance test procedure, 241-SY-101/241-C-106 shot loading system

International Nuclear Information System (INIS)

Ostrom, M.J.

1994-01-01

This Acceptance Test Procedure is for the 241-SY-101/241-C-106 Shot Loading System. The procedure will test the components of the Shot Loading System and its capability of adequately loading shot into the annular space of the Container. The loaded shot will provide shielding as required for transporting and storage of a contaminated pump after removal from the tank. This test serves as verification that the SLS is acceptable for use in the pump removal operations for Tanks 241-SY-101, 241-C-106 and 241-AY-102. The pump removal operation for these three tanks will be performed by two different organizations with different equipment, but the Shot Loading System will be compatible between the two operations

Investigation on a Novel Discontinuous Pulse-Width Modulation Algorithm for Single-phase Voltage Source Rectifier

DEFF Research Database (Denmark)

Qu, Hao; Yang, Xijun; Guo, Yougui

2014-01-01

Single-phase voltage source converter (VSC) is an important power electronic converter (PEC), including single-phase voltage source inverter (VSI), single-phase voltage source rectifier (VSR), single-phase active power filter (APF) and single-phase grid-connection inverter (GCI). Single-phase VSC...

Upper body strength and power are associated with shot speed in men's ice hockey

Directory of Open Access Journals (Sweden)

Juraj Bežák

2017-06-01

Full Text Available Background: Recent studies that addressed shot speed in ice hockey have focused on the relationship between shot speed and variables such as a player's skills or hockey stick construction and its properties. There has been a lack of evidence that considers the relationship between shot speed and player strength, particularly in players at the same skill level. Objective: The aim of this study was to identify the relationship between maximal puck velocity of two shot types (the wrist shot and the slap shot and players' upper body strength and power. Methods: Twenty male professional and semi-professional ice hockey players (mean age 23.3 ± 2.4 years participated in this study. The puck velocity was measured in five trials of the wrist shot and five trials of the slap shot performed by every subject. All of the shots were performed on ice in a stationary position 11.6 meters in front of an electronic device that measures the speed of the puck. The selected strength and power variables were: muscle power in concentric contraction in the countermovement bench press with 40 kg and 50 kg measured with the FiTRODyne Premium device; bench press one-repetition maximum; and grip strength measured by digital hand dynamometer. Results: The correlations between strength/power variables and the puck velocity in the wrist shot and the slap shot ranged between .29-.72 and .16-.62, respectively. Puck velocities produced by wrist shots showed significant correlations with bench press muscle power with 40 kg (p = .004 and 50 kg (p < .001; and one-repetition maximum in bench press (p = .004. The slap shot puck velocity was significantly associated with bench press muscle power with 40 kg (p = .014 and 50 kg (p = .004. Conclusions: This study provides evidence that there are significant associations between shot speed and upper body strength and power.

The Source Signature Estimator - System Improvements and Applications

Energy Technology Data Exchange (ETDEWEB)

Sabel, Per; Brink, Mundy; Eidsvig, Seija; Jensen, Lars

1998-12-31

This presentation relates briefly to the first part of the joint project on post-survey analysis of shot-by-shot based source signature estimation. The improvements of a Source Signature Estimator system are analysed. The notional source method can give suboptimal results when not inputting the real array geometry, i.e. actual separations between the sub-arrays of an air gun array, to the notional source algorithm. This constraint has been addressed herein and was implemented for the first time in the field in summer 1997. The second part of this study will show the potential advantages for interpretation when the signature estimates are then to be applied in the data processing. 5 refs., 1 fig.

Rotary peening with captive shot

International Nuclear Information System (INIS)

1998-02-01

Roto Peen with captive shot removes coatings and surface contamination from concrete floors. The objective of treating radioactively contaminated concrete floors during the Deactivation and Decommissioning (D and D) process is to reduce the surface contamination levels to meet regulatory criteria for unrestricted use. The US Department of Energy (DOE) Chicago Operations office and DOE's Federal Energy Technology Center (FETC) jointly sponsored a Large-Scale Demonstration Project (LSDP) at the Chicago Pile-5 Research Reactor (CP-5) at Argonne National Laboratory-East (ANL). The objective of the LSDP is to demonstrate potentially beneficial D and D technologies in comparison with current baseline technologies. As part of the LSDP, roto Peen with captive shot was demonstrated March 17--20, 1997, to treat a 20 x 25 ft area of radioactively contaminated concrete floor on the service level of the CP-5 building

Networks of ·/G/∞ queues with shot-noise-driven arrival intensities

NARCIS (Netherlands)

Koops, D.T.; Boxma, O.J.; Mandjes, M.R.H.

2017-01-01

We study infinite-server queues in which the arrival process is a Cox process (or doubly stochastic Poisson process), of which the arrival rate is given by a shot-noise process. A shot-noise rate emerges naturally in cases where the arrival rate tends to exhibit sudden increases (or shots) at random

Single-pulse x-ray diffraction using polycapillary optics for in situ dynamic diffraction

Energy Technology Data Exchange (ETDEWEB)

Maddox, B. R., E-mail: maddox3@llnl.gov; Akin, M. C., E-mail: akin1@llnl.gov; Teruya, A.; Hunt, D.; Hahn, D.; Cradick, J. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Morgan, D. V. [National Security Technologies LLC, Los Alamos, New Mexico 87544 (United States)

2016-08-15

Diagnostic use of single-pulse x-ray diffraction (XRD) at pulsed power facilities can be challenging due to factors such as the high flux and brightness requirements for diffraction and the geometric constraints of experimental platforms. By necessity, the x-ray source is usually positioned very close, within a few inches of the sample. On dynamic compression platforms, this puts the x-ray source in the debris field. We coupled x-ray polycapillary optics to a single-shot needle-and-washer x-ray diode source using a laser-based alignment scheme to obtain high-quality x-ray diffraction using a single 16 ns x-ray pulse with the source >1 m from the sample. The system was tested on a Mo sample in reflection geometry using 17 keV x-rays from a Mo anode. We also identified an anode conditioning effect that increased the x-ray intensity by 180%. Quantitative measurements of the x-ray focal spot produced by the polycapillary yielded a total x-ray flux on the sample of 3.3 ± 0.5 × 10{sup 7} molybdenum Kα photons.

Modeling and Design of High-Efficiency Single-Photon Sources

DEFF Research Database (Denmark)

Gregersen, Niels; Nielsen, Per Kær; Mørk, Jesper

2013-01-01

be electrically driven. Several design strategies addressing these requirements have been proposed. In the cavity-based source, light emission is controlled using resonant cavity quantum electrodynamics effects, whereas in the waveguide-based source, broadband electric field screening effects are employed......Solid-state sources capable of emitting single photons on demand are of great interest in quantum information applications. Ideally, such a source should emit exactly one photon into the collection optics per trigger, the emitted photons should be indistinguishable, and the source should...

Single-shot measurements of low emittance beams from laser-plasma accelerators comparing two triggered injection methods

Science.gov (United States)

van Tilborg, Jeroen

2017-10-01

The success of laser plasma accelerator (LPA) based applications, such as a compact x-ray free electron laser (FEL), relies on the ability to produce electron beams with excellent 6D brightness, where brightness is defined as the ratio of charge to the product of the three normalized emittances. As such, parametric studies of the emittance of LPA generated electron beams are essential. Profiting from a stable and tunable LPA setup, combined with a carefully designed single-shot energy-dispersed emittance diagnostic, we present a direct comparison of charge dependent emittance measurements of electron beams generated by two different injection mechanisms: ionization injection and shock-induced density down-ramp injection. Both injection mechanisms have gained in popularity in recent years due to their demonstrated stable LPA performance. For the down-ramp injection configuration, normalized emittances a factor of two lower were recorded: less than 1 micron at spectral charge densities up to 2 pC/MeV. For both injection mechanisms, a contributing correlation of space charge to the emittance was identified. This measurement technique in general, and these results specifically, are critical to the evaluation of LPA injection methods and development of high-quality LPA beam lines worldwide. This work is supported by the U.S. DOE under Contract No. DE-AC02-05CH11231, by the U.S. DOE NNSA, DNN R&D (NA22), by the National Science Foundation under Grant No. PHY-1415596, and by the Gordon and Betty Moore Foundation under Grant ID GBMF4898.

The wear and corrosion resistance of shot peened-nitrided 316L austenitic stainless steel

International Nuclear Information System (INIS)

Hashemi, B.; Rezaee Yazdi, M.; Azar, V.

2011-01-01

Research highlights: → Shot peening-nitriding increased the wear resistance and surface hardness of samples. → This treatment improved the surface mechanical properties. → Shot peening alleviates the adverse effects of nitriding on the corrosion behavior. -- Abstract: 316L austenitic stainless steel was gas nitrided at 570 o C with pre-shot peening. Shot peening and nitriding are surface treatments that enhance the mechanical properties of surface layers by inducing compressive residual stresses and formation of hard phases, respectively. The structural phases, micro-hardness, wear behavior and corrosion resistance of specimens were investigated by X-ray diffraction, Vickers micro-hardness, wear testing, scanning electron microscopy and cyclic polarization tests. The effects of shot peening on the nitride layer formation and corrosion resistance of specimens were studied. The results showed that shot peening enhanced the nitride layer formation. The shot peened-nitrided specimens had higher wear resistance and hardness than other specimens. On the other hand, although nitriding deteriorated the corrosion resistance of the specimens, cyclic polarization tests showed that shot peening before the nitriding treatment could alleviate this adverse effect.

High brightness single photon sources based on photonic wires

DEFF Research Database (Denmark)

Claudon, J.; Bleuse, J.; Bazin, M.

2009-01-01

We present a novel single-photon-source based on the emission of a semiconductor quantum dot embedded in a single-mode photonic wire. This geometry ensures a very large coupling (> 95%) of the spontaneous emission to the guided mode. Numerical simulations show that a photon collection efficiency...

Entangling quantum-logic gate operated with an ultrabright semiconductor single-photon source.

Science.gov (United States)

Gazzano, O; Almeida, M P; Nowak, A K; Portalupi, S L; Lemaître, A; Sagnes, I; White, A G; Senellart, P

2013-06-21

We demonstrate the unambiguous entangling operation of a photonic quantum-logic gate driven by an ultrabright solid-state single-photon source. Indistinguishable single photons emitted by a single semiconductor quantum dot in a micropillar optical cavity are used as target and control qubits. For a source brightness of 0.56 photons per pulse, the measured truth table has an overlap with the ideal case of 68.4±0.5%, increasing to 73.0±1.6% for a source brightness of 0.17 photons per pulse. The gate is entangling: At a source brightness of 0.48, the Bell-state fidelity is above the entangling threshold of 50% and reaches 71.0±3.6% for a source brightness of 0.15.

ZAPP shot summary

Energy Technology Data Exchange (ETDEWEB)

Loisel, Guillaume Pascal [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

2015-10-01

This was the second Z Astrophysical Plasma Properties (ZAPP) fundamental science shot series of 2015. ZAPP experiments measure fundamental properties of atoms in plasmas to solve the following important astrophysical puzzles: Why can’t we accurately model the opacity of Fe at the convection zone boundary in the Sun? How accurate are the photoionization models used to interpret data from xray satellite observations? and Why doesn’t spectral fitting provide the correct properties for White Dwarfs?

The finite element analysis for prediction of residual stresses induced by shot peening

International Nuclear Information System (INIS)

Kim, Cheol; Yang, Won Ho; Sung, Ki Deug; Cho, Myoung Rae; Ko, Myung Hoon

2000-01-01

The shot peening is largely used for a surface treatment in which small spherical parts called shots are blasted on a surface of a metallic components with velocities up to 100m/s. This treatment leads to an improvement of fatigue behavior due to the developed compressive residual stresses, and so it has gained widespread acceptance in the automobile and aerospace industries. The residual stress profile on surface layer depends on the parameters of shot peening, which are, shot velocity, shot diameter, coverage, impact angle, material properties etc. and the method to confirm this profile is only measurement by X-ray diffractometer. Despite its importance to automobile and aerospace industries, little attention has been devoted to the accurate modeling of the process. In this paper, the simulation technique is applied to predict the magnitude and distribution of the residual stress and plastic deformation caused by shot peening with the help of the finite element analysis

Shot-peening of carbonitrided steel: influence of the process on the mechanical state

Directory of Open Access Journals (Sweden)

François M.

2010-06-01

Full Text Available Residual stresses have a significant role in affecting engineering properties of materials and shot peening process is an effective production technique to ensure required residual stress levels. This paper presents an analysis of an orthogonal design of experiment to establish an empirical relationship between main parameters of shot peening process and residual stress profiles for a carbonitrided steel. The hardening / softening evolution of the material is followed using hardness and diffraction peak width. Four critical peening parameters, i.e. shot size, incident angle, exposure time, airblast pressure, have been chosen and the range of peening conditions are established by using the Taguchi technique. In this study, a shot velocity measurement system is used to obtain the on-line velocity during the peening process and the relationship between the maximum compressive residual stresses and the shot velocity is also developed. Analysis of the experimental data showed that it is possible to optimize the shot peening process by an effective control of process parameters.

Temperature dependence of shot noise in double barrier magnetic tunnel junctions

Science.gov (United States)

Niu, Jiasen; Liu, Liang; Feng, J. F.; Han, X. F.; Coey, J. M. D.; Zhang, X.-G.; Wei, Jian

2018-03-01

Shot noise reveals spin dependent transport properties in a magnetic tunnel junction. We report measurement of shot noise in CoFeB/MgO/CoFeB/MgO/CoFeB double barrier magnetic tunnel junctions, which shows a strong temperature dependence. The Fano factor used to characterize shot noise increases with decreasing temperature. A sequential tunneling model can be used to account for these results, in which a larger Fano factor results from larger spin relaxation length at lower temperatures.

A study on corrosive behavior of spring steel by shot-peening process

International Nuclear Information System (INIS)

An, Jae Pil; Park, Keyung Dong

2004-01-01

In this study, the influence of shot peening on the corrosion was investigated on spring steel immersed in 3.5% NaCl. The immersion test was performed on the two kinds of specimens. Corrosion potential, polarization curve, residual stress and etc. were investigated from experimental results. From test results, the effect of shot peening on the corrosion was evaluated. In case of corrosion potential, shot peened specimen shows more activated negative direction as compared with parent metal. Surface of specimen, which is treated with the shot peened, is placed as more activated state against inner base metal. It can cause the anti-corrosion effect on the base metal

Development of Adaptive Feedback Control System of Both Spatial and Temporal Beam Shaping for UV-Laser Light Source for RF Gun

CERN Document Server

Tomizawa, H; Dewa, H; Hanaki, H; Kobayashi, T; Mizuno, A; Suzuki, S; Taniuchi, T; Yanagida, K

2004-01-01

The ideal spatial and temporal profiles of a shot-by-shot single laser pulse are essential to suppress the emittance growth of the electron beam from a photo-cathode rf gun. We have been developing highly qualified UV-laser pulse as a light source of the rf gun for an injector candidate of future light sources. The gun cavity is a single-cell pillbox, and the copper inner wall is used as a photo cathode. The electron beam was accelerated up to 4.1 MeV at the maximum electric field on the cathode surface of 175 MV/m. For emittance compensation, two solenoid coils were used. As the first test run, with a microlens array as a simple spatial shaper, we obtained a minimum emittance value of 2 π·mm·mrad with a beam energy of 3.1 MeV, holding its charge to 0.1 nC/bunch. In the next test run, we prepared a deformable mirror for spatial shaping, and a spatial light modulator based on fused-silica plates for temporal shaping. We applied the both adaptive optics to automatically shape the bot...

77 FR 36272 - SunShot Prize: America's Most Affordable Rooftop

Science.gov (United States)

2012-06-18

...The Department of Energy (DOE) announces in this notice the release of the SunShot Prize: America's Most Affordable Rooftop Solar for public comment. Interested persons are encouraged to learn about the SunShot Prize: America's Most Affordable Rooftop rules at eere.energy.gov/solar/sunshot/prize.html.

The Numerical FEM Model of the Kinematics of the Vibratory Shot Peening Process

Directory of Open Access Journals (Sweden)

Stanisław Bławucki

2017-12-01

Full Text Available The paper presents the results of numerical calculations, with the finite element method in the ABAQUS program environment, of the vibratory shot peening process with loose peening elements. The behaviour of shot peening elements was analysed in the kinematic aspect. The impact of the initial deployment of vibratory shot peening elements on their behaviour during processing was investigated, including the displacement, velocity, acceleration and the number of collisions. The way of determining the effectiveness of the processing with the vibratory shot peening was illustrated.

Radiologically contaminated lead shot reuse at the Idaho National Engineering Laboratory (INEL)

International Nuclear Information System (INIS)

Heileson, W.M.; Grant, R.P.

1995-01-01

This project involved the utilization of radioactively contaminated lead shot located at the Radioactive Waste Management Complex (RWMC) for radiation shielding on a radioactive liquid process tank located at Argonne National Laboratory-West (ANL-W). The use of previously contaminated shot precludes the radioactive contamination of clean shot. With limited treatment and disposal options for contaminated lead shot, the reuse of lead for shielding is significant due to the inherent characteristic of becoming a mixed waste when radiologically contaminated. The INEL conducted a lead cleanup campaign in 1990. This was designed to ensure control of potential Resource Conservation and Recovery Act (RCRA) regulated waste. Contaminated lead from throughout the INEL, was containerized per the lead Waste Acceptance Criteria at the generator sites. Limited areas at the INEL are designated for mixed waste storage. As a result, some of the lead was stored at the RWMC in the air support weather shield (ASWS). This lead was contaminated with small amounts of fission product contamination. The lead was in the form of shot, brick, sheet, casks, and other various sized pieces. In 1993, ANL-W identified a need for lead shot to be used as shielding in a radioactive liquid waste storage and processing tank at the Fuel Cycle Facility (FCF). The contaminated lead used on this project had been in storage as mixed waste at the RWMC. This paper will focus on the processes and problems encountered to utilize the contaminated lead shot

Robust shot-noise measurement for continuous-variable quantum key distribution

Science.gov (United States)

Kunz-Jacques, Sébastien; Jouguet, Paul

2015-02-01

We study a practical method to measure the shot noise in real time in continuous-variable quantum key distribution systems. The amount of secret key that can be extracted from the raw statistics depends strongly on this quantity since it affects in particular the computation of the excess noise (i.e., noise in excess of the shot noise) added by an eavesdropper on the quantum channel. Some powerful quantum hacking attacks relying on faking the estimated value of the shot noise to hide an intercept and resend strategy were proposed. Here, we provide experimental evidence that our method can defeat the saturation attack and the wavelength attack.

Finite element modelling of coverage effects during shot peening of IN718

Energy Technology Data Exchange (ETDEWEB)

Zimmermann, Marc; Hoffmeister, Juergen [Inst. fuer Werkstoffkunde I, Karlsruhe Inst. of Tech. (Germany); Schulze, Volker [Inst. fur Produktionstechnik, Karlsruhe Inst. of Tech. (Germany)

2010-08-15

Current 3D shot peening simulation models proposed in literature do not take into account coverage as a process parameter influencing the residual state after shot peening. In this study a classic approach, using an ordered dimple pattern, and a new approach, using a stochastic dimple pattern were tested to describe the correlation between coverage, the surface topography and the residual stress state. Model verification was conducted based on X-ray and confocal white light microscopy measurements on shot peened test specimens. The test material was age hardened IN718. Simulations showed that the dimple pattern and the impact order of the shots can have a strong influence on the calculated macroscopic residual stress state. The stochastic approach enabled a realistic prediction of the surface topography and the residual stress state for arbitrary values of coverage while the classic approach strongly underestimated the number of shot impacts needed to achieve a certain value of coverage. (orig.)

Design and Implementation of Video Shot Detection on Field Programmable Gate Arrays

Directory of Open Access Journals (Sweden)

Jharna Majumdar

2012-09-01

Full Text Available Video has become an interactive medium of communication in everyday life. The sheer volume of video makes it extremely difficult to browse through and find the required data. Hence extraction of key frames from the video which represents the abstract of the entire video becomes necessary. The aim of the video shot detection is to find the position of the shot boundaries, so that key frames can be selected from each shot for subsequent processing such as video summarization, indexing etc. For most of the surveillance applications like video summery, face recognition etc., the hardware (real time implementation of these algorithms becomes necessary. Here in this paper we present the architecture for simultaneous accessing of consecutive frames, which are then used for the implementation of various Video Shot Detection algorithms. We also present the real time implementation of three video shot detection algorithms using the above mentioned architecture on FPGA (Field Programmable Gate Arrays.

Beauty and science in a shot

Science.gov (United States)

Ciceri, Piera

2017-04-01

Taking pictures has become a daily action for young. Photography is an essential component of many areas of science, has played a crucial role in the study of anatomy, botany, archeology, ... Still today it is a "scientific tool" in the school textbooks: pictures describe, make reality larger or smaller, faster or slower, show evidence and experimental results. But a photograph has the ability to move, engage and inspire viewers. That means that a photograph can build an emotional bridge between science and people. People and students can get closer to science through beautiful, evocative and expressive shot. In this project students are involved in taking pictures with a scientific and aesthetic content looking around, setting an experiment, watching nature, playing with light, point of wiew, colors and perspective. They have to write a short text and a title that explains the scientific content, why and how they have taken the picture. Both description and title should let increase curiosity, could looks fun or stress artistic aspects. Student show their shots in an official public event in Milan managed by a committee of science and photograph experts and in a local event to parents and local community. "Shots of science" is a project promoted by the italian national association "Scienza under 18", the Physic Department of "Università degli Studi di Milano" and the "Museo di fotografia contemporanea" of Cinisello Balsamo (MI) that help students in discussing about scientific and artistic aspects of their shots. This project contributes to develop digital skills (such as to manage digital images, to share documents, to learn about copyright and creative commons license), communication skills (such as to write a caption, public speaking, to use a picture to communicate), collaboration skills (such as to work with pairs, to respect scheduled times, to be positive in giving and taking into account suggestions) and artistic skills (to learn how to compose a good

Development of highly qualified UV-laser light source for rf gun

International Nuclear Information System (INIS)

Tomizawa, H.; Dewa, H.; Taniuchi, T.

2004-01-01

We have been developing stable and highly qualified UV-laser pulse as a light source of the rf gun for an injector candidate of future light sources. Our gun cavity is a single-cell pillbox, and the copper inner wall is used as a photo cathode. In present status, the short pulse energy stability of laser has been improved down to 1.3∼1.5% (rms; 10pps; 10000 shots) at the third harmonic generation. The long stability depends on the stability of modelocking at oscillator. In this improvement we just passively stabilized the system. We considered environmental controls in clean room to reduce optical damage accidents and constructed a new humidity-controlled clean room in 2003. And we re-installed the total laser system in this room in 2004. The relative humidity of this new clean room at room temperature is in a region of 50∼60 % with a stability of less than 2% (p-p). On the other hand, the ideal spatial and temporal profiles of a shot-by-shot single laser pulse are essential to suppress the emittance growth of the electron beam from a photo-cathode rf gun. This laser-shaping project has been started in two steps since 2002. As the first successful test run in 2002, with a microlens array as a simple spatial shaper, we obtained a minimum emittance value of 2π mm·mrad with a beam energy of 3.1 MeV, holding its charge to 0.1 nC/bunch. In the next test run in 2004, we prepared a deformable mirror for spatial shaping, and a spatial light modulator based on fused-silica plates for temporal shaping. We are applying the both adaptive optics to automatically shape the both spatial and temporal UV-laser profiles with a feedback routine at the same time. We report herein the principle and developing process of our laser beam quality control system. (author)

Finding the gap: An empirical study of the most effective shots in elite goalball.

Directory of Open Access Journals (Sweden)

Daniel Link

Full Text Available This research identifies which shots types in goalball are most likely to lead to a goal and herby provides background information for improving training and competition. Therefore, we observed 117 elite level matches including 20,541 shots played in the regular situation (3 vs. 3 using notational analysis. We characterized the shots by using their target sector (A-E, technique (traditional, rotation, trajectory (flat, bounce, angle (straight, diagonal and outcome (goal, violation, out, blocked. In our data, a χ2-test showed a significantly higher goal rate for men (3.9% compared to women (3.0%. For men, we found a significantly higher goal rate in the intersection sectors between players C (5.6%, D (4.9%, and in the outer sector A. In sector A, goal rate was higher only for straight shots (6.6%. Technique and trajectory did not affect goal rate for men, but flat shots showed a higher violation rate (3.2% compared to bounce shouts (2.0%. In women's goalball, goal rate was higher only on sector D (4.4%. Bounce-rotation shots were the most successful (5.5%. We conclude that men should focus on shots to sectors C and D (called pocket and straight shots to sector A, as long as there are no other tactical considerations. Women should shoot primarily towards the pocket. It might also be worth playing more bounce-rotation shots and practicing them in training.

Finding the gap: An empirical study of the most effective shots in elite goalball.

Science.gov (United States)

Link, Daniel; Weber, Christoph

2018-01-01

This research identifies which shots types in goalball are most likely to lead to a goal and herby provides background information for improving training and competition. Therefore, we observed 117 elite level matches including 20,541 shots played in the regular situation (3 vs. 3) using notational analysis. We characterized the shots by using their target sector (A-E), technique (traditional, rotation), trajectory (flat, bounce), angle (straight, diagonal and outcome (goal, violation, out, blocked). In our data, a χ2-test showed a significantly higher goal rate for men (3.9%) compared to women (3.0%). For men, we found a significantly higher goal rate in the intersection sectors between players C (5.6%), D (4.9%), and in the outer sector A. In sector A, goal rate was higher only for straight shots (6.6%). Technique and trajectory did not affect goal rate for men, but flat shots showed a higher violation rate (3.2%) compared to bounce shouts (2.0%). In women's goalball, goal rate was higher only on sector D (4.4%). Bounce-rotation shots were the most successful (5.5%). We conclude that men should focus on shots to sectors C and D (called pocket) and straight shots to sector A, as long as there are no other tactical considerations. Women should shoot primarily towards the pocket. It might also be worth playing more bounce-rotation shots and practicing them in training.

Numerical simulation of the shot peening process under previous loading conditions

International Nuclear Information System (INIS)

Romero-Ángeles, B; Urriolagoitia-Sosa, G; Torres-San Miguel, C R; Molina-Ballinas, A; Benítez-García, H A; Vargas-Bustos, J A; Urriolagoitia-Calderón, G

2015-01-01

This research presents a numerical simulation of the shot peening process and determines the residual stress field induced into a component with a previous loading history. The importance of this analysis is based on the fact that mechanical elements under shot peening are also subjected to manufacturing processes, which convert raw material into finished product. However, material is not provided in a virgin state, it has a previous loading history caused by the manner it is fabricated. This condition could alter some beneficial aspects of the residual stress induced by shot peening and could accelerate the crack nucleation and propagation progression. Studies were performed in beams subjected to strain hardening in tension (5ε y ) before shot peening was applied. Latter results were then compared in a numerical assessment of an induced residual stress field by shot peening carried out in a component (beam) without any previous loading history. In this paper, it is clearly shown the detrimental or beneficial effect that previous loading history can bring to the mechanical component and how it can be controlled to improve the mechanical behavior of the material

Effects of Rayleigh damping, friction and rate-dependency on 3D residual stress simulation of angled shot peening

International Nuclear Information System (INIS)

Kim, Taehyung; Lee, Hyungyil; Hyun, Hong Chul; Jung, Sunghwan

2013-01-01

Highlights: ► We propose a 3D FE model to study peening residual stress involving angled shots. ► The FE model set with plastic shot are found to best match the X-ray diffraction data. ► The model provides 3D multi-shot impact FE solution with various incidence angles. - Abstract: In this study, we propose a 3D finite element (FE) model to study shot peening involving angled shots. Using the FE model for angled shot peening, we examine relationships with the residual stress introduced by shot peening of the factors such as the Rayleigh damping in the material, dynamic friction, and the rate dependency of the material and systematically integrate them with the FE model. The FE model is set with rigid shot, elastic shot, and plastic shot respectively. Plastic deformation of the shot is also explored with the FE model. The FE model is applied to study angled multi-shots. The FE results are verified with experimental data using X-ray diffraction (XRD). The FE model set with plastic shot are found to best match the XRD results validating accuracy of the 3D FE model properly integrated with the factors and plastically deformable shot ball. The proposed model will serve to simulate actual shot peening cases, which generally involve multi-shots with various incidence angles

SnapShot: The Bacterial Cytoskeleton.

Science.gov (United States)

Fink, Gero; Szewczak-Harris, Andrzej; Löwe, Jan

2016-07-14

Most bacteria and archaea contain filamentous proteins and filament systems that are collectively known as the bacterial cytoskeleton, though not all of them are cytoskeletal, affect cell shape, or maintain intracellular organization. To view this SnapShot, open or download the PDF. Copyright © 2016. Published by Elsevier Inc.

Use and Perceptions of Caffeinated Energy Drinks and Energy Shots in Canada.

Science.gov (United States)

Wiggers, Danielle; Reid, Jessica L; White, Christine M; Hammond, David

2017-12-01

In Canada, energy drinks and energy shots are currently classified and regulated differently (food and drugs versus natural health products, respectively), on the assumption that they are used and perceived differently. The current study examined potential differences in use and perceptions of energy drinks and shots. An online survey was conducted in 2015 using a national commercial online panel of youth and young adults aged 12-24 years (n=2,040 retained for analysis in 2016). Participants were randomized to view an image of an energy shot or drink, and were asked about 14 potential reasons for using the product. Past consumption of each product was also assessed. Chi-square and t-tests were conducted to examine differences in use and perceptions between products. Overall, 15.6% of respondents reported using both energy shots and drinks. Of all respondents, ordering of the reasons for use of each product was comparable. Despite differences in prevalence of ever-use of energy shots and drinks, consumption patterns and perceived reasons for using the products are similar. The findings provide little support for regulating energy shots differently than energy drinks. Copyright © 2017 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

A focal-spot diagnostic for on-shot characterization of high-energy petawatt lasers.

Science.gov (United States)

Bromage, J; Bahk, S-W; Irwin, D; Kwiatkowski, J; Pruyne, A; Millecchia, M; Moore, M; Zuegel, J D

2008-10-13

An on-shot focal-spot diagnostic for characterizing high-energy, petawatt-class laser systems is presented. Accurate measurements at full energy are demonstrated using high-resolution wavefront sensing in combination with techniques to calibrate on-shot measurements with low-power sample beams. Results are shown for full-energy activation shots of the OMEGA EP Laser System.

The effect of court location and available time on the tactical shot selection of elite squash players.

Science.gov (United States)

Vučković, Goran; James, Nic; Hughes, Mike; Murray, Stafford; Sporiš, Goran; Perš, Janez

2013-01-01

No previous research in squash has considered the time between shots or the proximity of the ball to a wall, which are two important variables that influence shot outcomes. The aim of this paper was to analyse shot types to determine the extent to which they are played in different court areas and a more detailed analysis to determine whether the time available had an influence on the shot selected. Ten elite matches, contested by fifteen of the world's top right handed squash players (age 27 ± 3.2, height 1.81 ± 0.06 m, weight 76.3 ± 3.7 kg), at the men's World Team Championships were processed using the SAGIT/Squash tracking system with shot information manually added to the system. Results suggested that shot responses were dependent upon court location and the time between shots. When these factors were considered repeatable performance existed to the extent that one of two shots was typically played when there was limited time to play the shot (tactics affect shot selections. Key pointsPrevious research has suggested that a playing strategy, elements decided in advance of the match, may be evident for elite players by examining court location and preceding shot type, however these parameters alone are unlikely to be sufficient predictors.At present there is no known analysis in squash, or indeed in any of the racket sports, that has quantified the time available to respond to different shot types. An understanding of the time interval between shots and the movement characteristics of the player responding to different shots according to the court positions might facilitate a better understanding of the dynamics that determine shot selection.Some elements of a general playing strategy were evident e.g. predominately hitting to the back left of the court, but tactical differences in shot selection were also evident on the basis of court location and time available to play a shot.

Study on the use of types of shots in Valencian Handball on professional players

Directory of Open Access Journals (Sweden)

José Antonio Martínez Carbonell

2013-01-01

Full Text Available Due to the shortage of studies of analysis in Valencian ball, we have centred this study on this sport. The aim of study has been to analyze and to quantify the types of shots , and to compare the same ones between the positions of game of 1st game line (resto and 2nd game line (medio. Analysis of 6 games of the 19th Professional League of Stand and rope 2009-2010 was carried out so i, and specifically of 12 players, using Sports Code analysis software. The results indicate significant differences (p<0.05 between the shots carried out by first game line player and second game line in the rebound and rebound-shot all of them of right and left hand,and stand shot right hand; being almost realitzados only by players from the first game line position. At the same time we find data which demonstrate us by another band used mainly by second game line players beatings, these have been volley shot, volley shot after bounce, volley shot under the line of the shoulders, palm shot and horizontal shot all of them of right hand. As conclusion of the study, we have obtained that depending on the position of game the players use a few types of I throb or others. Therefore, we affirm, that the analysis of the high performance in stand and rope from the advances of the technologies, a valuable information contributes us to establish specific bosses of training.

Single-photon sources for quantum technologies - Results of the joint research project SIQUTE

DEFF Research Database (Denmark)

Kück, S.; López, M.; Rodiek, B.

2017-01-01

In this presentation, the results of the joint research project “Single-Photon Sources for Quantum Technologies” (SIQUTE) [1] will be presented. The focus will be on the development of absolutely characterized single-photon sources, on the realization of an efficient waveguide-based single-photon......-photon source at the telecom wavelengths of 1.3 µm and 1.55 µm, on the implementation of the quantum-enhanced resolution in confocal fluorescence microscopy and on the development of a detector for very low photon fluxes...

Non-contrast-enhanced imaging of haemodialysis fistulas using quiescent-interval single-shot (QISS) MRA: a feasibility study

International Nuclear Information System (INIS)

Okur, A.; Kantarci, M.; Karaca, L.; Yildiz, S.; Sade, R.; Pirimoglu, B.; Keles, M.; Avci, A.; Çankaya, E.; Schmitt, P.

2016-01-01

Aim: To assess the efficiency of a novel quiescent-interval single-shot (QISS) technique for non-contrast-enhanced magnetic resonance angiography (MRA) of haemodialysis fistulas. Materials and methods: QISS MRA and colour Doppler ultrasound (CDU) images were obtained from 22 haemodialysis patients with end-stage renal disease (ESRD). A radiologist with extensive experience in vascular imaging initially assessed the fistulas using CDU. Two observers analysed each QISS MRA data set in terms of image quality, using a five-point scale ranging from 0 (non-diagnostic) to 4 (excellent), and lumen diameters of all segments were measured. Results: One hundred vascular segments were analysed for QISS MRA. Two anastomosis segments were considered non-diagnostic. None of the arterial or venous segments were evaluated as non-diagnostic. The image quality was poorer for the anastomosis level compared to the other segments (p<0.001 for arterial segments, and p<0.05 for venous segments), while no significant difference was determined for other vascular segments. Conclusion: QISS MRA has the potential to provide valuable complementary information to CDU regarding the imaging of haemodialysis fistulas. In addition, QISS non-enhanced MRA represents an alternative for assessment of haemodialysis fistulas, in which the administration of iodinated or gadolinium-based contrast agents is contraindicated. - Highlights: • Close monitoring and early intervention in hemodialysis fistulas may prolong longevity fistulas. • DopplerUS, contrast enhanced CT and MRI are using assessment of hemodialysis fistulas. • QISS nonenhanced MR angiography represents an alternative for assessment of hemodialysis fistulas.

Kinematic and kinetic analysis of overhand, sidearm and underhand lacrosse shot techniques.

Science.gov (United States)

Macaulay, Charles A J; Katz, Larry; Stergiou, Pro; Stefanyshyn, Darren; Tomaghelli, Luciano

2017-12-01

Lacrosse requires the coordinated performance of many complex skills. One of these skills is shooting on the opponents' net using one of three techniques: overhand, sidearm or underhand. The purpose of this study was to (i) determine which technique generated the highest ball velocity and greatest shot accuracy and (ii) identify kinematic and kinetic variables that contribute to a high velocity and high accuracy shot. Twelve elite male lacrosse players participated in this study. Kinematic data were sampled at 250 Hz, while two-dimensional force plates collected ground reaction force data (1000 Hz). Statistical analysis showed significantly greater ball velocity for the sidearm technique than overhand (P  0.05). Kinematic and kinetic variables were not significantly correlated to shot accuracy or velocity across all shot types; however, when analysed independently, the lead foot horizontal impulse showed a negative correlation with underhand ball velocity (P = 0.042). This study identifies the technique with the highest ball velocity, defines kinematic and kinetic predictors related to ball velocity and provides information to coaches and athletes concerned with improving lacrosse shot performance.

Shot peening speed measurements using lidar technology

DEFF Research Database (Denmark)

Angelou, Nikolas; Zhang, Xiaodan; Sjöholm, Mikael

The shot peening technique is used for the surface modification of metallic components that are part of wind turbines, such as gears, bolts and blade coatings to prevent erosion. An important parameter of this technique is the dynamic energy of emitted shots. In this context the objective......, the risk of damaging the peening machine by installing an instrument inside the chamber during operation is eliminated by this approach. Laser anemometers are being researched and developed in the department of Wind Energy, mainly in the framework of the WindScanner.dk infrastructure project [1], but also...... validated and used in monitoring the wind conditions around wind turbines (wake and inflow), over complex terrain as well as offshore....

RF Shot Noise Measurements in Au Atomic-scale Junctions

Science.gov (United States)

Chen, Ruoyu

Conduction electrons are responsible for many physical or chemical phenomena in condensed matter systems, and their behavior can be directly studied by electronic transport measurements. In conventional transport measurements, conductance or resistance is usually the focus. Such a measurement can be as simple as a quick two terminal DC check by a multi-meter, or a more sophisticated lock-in measurement of multiple higher harmonic signals synchronized to different frequencies. Conductance carries direct information about the quasi-particle density of states and the local electronic distributions, which are usually Fermi-Dirac distribution. Conductance is modified or dominated by scattering from defacts or interfaces, and could also reflect the spin-spin exchange interactions or inelastic couplings with phonons and photons. Naturally one can ask the question: is there anything else we can measure electronically, which carries extra information that a conductance measurement does not provide? One answer to this question is the electronic noise. While the conductance reflects the average charge conduction ability of a system, noise describes how the physical quantities fluctuate around their average values. Some of the fluctuations carry information about their physical origins. This thesis will focus on one particular type of the electronic noise shot noise, but other types of noise will also be introduced and discussed. We choose to measure the radio frequency component of shot noise, combining with a modulated lock-in detection technique, which provides a method to largely get rid of other unwanted low-frequency noise signals. Au atomic-scale junctions are the systems we studied here. Au is relatively well understood and will not generate too many complications, so it's ideal as the first platform for us to understand both shot noise itself and our RF technique. On the other hand, the atomic scale raises fundamental questions about electronic transport and local

The Distribution of the Interval between Events of a Cox Process with Shot Noise Intensity

Directory of Open Access Journals (Sweden)

Angelos Dassios

2008-01-01

Full Text Available Applying piecewise deterministic Markov processes theory, the probability generating function of a Cox process, incorporating with shot noise process as the claim intensity, is obtained. We also derive the Laplace transform of the distribution of the shot noise process at claim jump times, using stationary assumption of the shot noise process at any times. Based on this Laplace transform and from the probability generating function of a Cox process with shot noise intensity, we obtain the distribution of the interval of a Cox process with shot noise intensity for insurance claims and its moments, that is, mean and variance.

Music video shot segmentation using independent component analysis and keyframe extraction based on image complexity

Science.gov (United States)

Li, Wei; Chen, Ting; Zhang, Wenjun; Shi, Yunyu; Li, Jun

2012-04-01

In recent years, Music video data is increasing at an astonishing speed. Shot segmentation and keyframe extraction constitute a fundamental unit in organizing, indexing, retrieving video content. In this paper a unified framework is proposed to detect the shot boundaries and extract the keyframe of a shot. Music video is first segmented to shots by illumination-invariant chromaticity histogram in independent component (IC) analysis feature space .Then we presents a new metric, image complexity, to extract keyframe in a shot which is computed by ICs. Experimental results show the framework is effective and has a good performance.

Transport, shot noise, and topology in AC-driven dimer arrays

Science.gov (United States)

Niklas, Michael; Benito, Mónica; Kohler, Sigmund; Platero, Gloria

2016-11-01

We analyze an AC-driven dimer chain connected to a strongly biased electron source and drain. It turns out that the resulting transport exhibits fingerprints of topology. They are particularly visible in the driving-induced current suppression and the Fano factor. Thus, shot noise measurements provide a topological phase diagram as a function of the driving parameters. The observed phenomena can be explained physically by a mapping to an effective time-independent Hamiltonian and the emergence of edge states. Moreover, by considering quantum dissipation, we determine the requirements for the coherence properties in a possible experimental realization. For the computation of the zero-frequency noise, we develop an efficient method based on matrix-continued fractions.

IMPACT OF VIBRATORY AND ROTATIONAL SHOT PEENING ONTO SELECTED PROPERTIES OF TITANIUM ALLOY SURFACE LAYER

Directory of Open Access Journals (Sweden)

Kazimierz Zaleski

2014-06-01

Full Text Available This study presents the results of tests on impact of vibratory and rotational shot peening of the Ti6A12Mo2Cr titanium alloy onto the processed object surface roughness and surface layer microhardness. The external surfaces of ring-shaped samples were shot peened. The preceding process consisted of turning with a cubic boron nitride blade knife. Steel beads, having a diameter of 6 mm, were used as a processing medium. The variable parameters of shot peening were vibrator amplitude and shot peening time. The range of recommended technological parameters for vibratory and rotational shot peening was determined. As a result of shot peening, the surface roughness could be reduced by approximately 4 times and the surface layer could be hardened to the depth of approximately 0.4 mm.

Influence of the shot-peening treatment on the CRF gearing behaviour

International Nuclear Information System (INIS)

Molinie, D.; Lemaire, E.; Randrianarivo, L.; Dorier, C.

1998-01-01

Surface damage are observed in service on CRF case-hardened cases. Such damage is like surface fatigue which appears in the form of frosting and can come to a micro-spalling or even a spalling damage. Survey and studies realised on gears affected by such damage, led EDF and the manufacturer to search for appropriated solutions since 1985 (optimisation of the gear bottom profile, care of the grinding and the thermochemical processing, use of oils with higher viscosity). Simulations on a running wheel device can reproduce the meshing conditions on simplified specimen. The aim is to study the influence of residual stresses following a severe grinding and shot peening treatments. An empiric selection was realised among different shot peening treatments. Endurance tests are realised on case-hardened gears with or without shot-peening treatments. Compared with standard grinded gears, it appears that the shot-peening selected increases up to 40% the gear lifetime till extended spalling. (authors)

Differential diagnosis of pituitary adenomas and Rathke's cleft cysts by diffusion-weighted MRI using single-shot fast spin echo technique

International Nuclear Information System (INIS)

Abe, Takumi; Izumiyama, Hitoshi; Fukuda, Ataru; Tanioka, Daisuke; Kunii, Norihiko; Komatsu, Daisuke; Fujita, Shogo; Ukisu, Ryutaro; Moritani, Toshio

2002-01-01

The purpose of the present study was to prospectively evaluate the diagnostic ability of diffusion-weighted magnetic resonance imaging (DWI) using single-shot fast spin echo (SSFSE) technique to discriminate pituitary adenomas from Rathke's cleft cysts. DWIs were obtained from 40 patients with pathologically proven pituitary macroadenomas and 15 patients with proven Rathke's cleft cysts. Pituitary adenomas were divided into 27 cases with solid components alone, five with non-hemorrhagic large cysts, and eight with intratumoral hemorrhage. On SSFSE DWI, solid components of pituitary adenomas revealed iso or slightly increased intensity and intratumoral hemorrhage showed higher intensity than normal brain parenchyma, whereas Rathke's cleft cysts and intratumoral cysts demonstrated very low intensity. SSFSE DWI did not display the susceptibility artifacts that are seen close to the skull base and sinonasal cavities on echo planar diffusion imaging. On the basis of our preliminary findings, DWI may enable us to differentiate pituitary adenomas with only solid components and hemorrhagic pituitary adenomas appearing hyperintense on T1-weighted images from Rathke's cleft cysts without administration of gadolinium-DTPA. SSFSE DWI appears to be a useful technique for characterizing pituitary diseases without the susceptibility artifacts. Our study is the first report to demonstrate the identification of pituitary disorders on SSFSE DWI. (author)

Shot H3837: Darht's First Dual-Axis Explosive Experiment

Science.gov (United States)

Mendez, Jacob; McNeil, Wendy Vogan; Harsh, James; Hull, Lawrence

2011-06-01

Test H3837 was the first explosive shot performed in front of both flash x-ray axes at the Los Alamos Dual Axis Radiographic HydroTest (DARHT) facility. Executed in November 2009, the shot was an explosively-driven metal flyer plate in a series of experiments designed to explore equation-of-state properties of shocked materials. Imaging the initial shock wave traveling through the flyer plate, DARHT Axis II captured the range of motion from the shock front emergence in the flyer to breakout at the free surface; the Axis I pulse provided a perpendicular perspective of the shot at a time coinciding with the third pulse of Axis II. Since the days of the Manhattan Project, penetrating radiography with multiple frames from different viewing angles has remained a high-profile goal at the Laboratory. H3837 is merely the beginning of a bright future for two-axis penetrating radiography.

Nonenhanced ECG-gated quiescent-interval single-shot MRA (QISS-MRA) of the lower extremities: Comparison with contrast-enhanced MRA

Energy Technology Data Exchange (ETDEWEB)

Klasen, J. [Department of Diagnostic and Interventional Radiology, University of Duesseldorf, Medical Faculty, Duesseldorf (Germany); Blondin, D., E-mail: blondin@med.uni-duesseldorf.de [Department of Diagnostic and Interventional Radiology, University of Duesseldorf, Medical Faculty, Duesseldorf (Germany); Schmitt, P. [Siemens AG, Healthcare Sector, Erlangen (Germany); Bi, X. [Siemens Healthcare, Chicago, IL (United States); Sansone, R. [Department of Cardiology, University of Duesseldorf, Medical Faculty, Duesseldorf (Germany); Wittsack, H.-J.; Kroepil, P.; Quentin, M.; Kuhlemann, J.; Miese, F. [Department of Diagnostic and Interventional Radiology, University of Duesseldorf, Medical Faculty, Duesseldorf (Germany); Heiss, C.; Kelm, M. [Department of Cardiology, University of Duesseldorf, Medical Faculty, Duesseldorf (Germany); Antoch, G.; Lanzman, R.S. [Department of Diagnostic and Interventional Radiology, University of Duesseldorf, Medical Faculty, Duesseldorf (Germany)

2012-05-15

Aim: To evaluate electrocardiogram (ECG)-gated quiescent-interval single-shot magnetic resonance angiography (QISS-MRA) for nonenhanced assessment of peripheral artery occlusive disease (PAOD) using contrast-enhanced MRA (CE-MRA) as the reference standard. Materials and methods: Twenty-seven patients (mean age 66.6 {+-} 10.8 years) with PAOD were included in the study. QISS-MRA and CE-MRA of the lower extremity were performed using a 1.5 T MR scanner. In each patient, subjective image quality and the degree of stenosis were evaluated on a four-point scale for 15 predefined arterial segments. Results: Twenty-five of the 27 patients were considered for analysis. Subjective image quality of QISS-MRA was significantly lower for the distal aorta, pelvic arteries, and femoral arteries as compared to CE-MRA (p < 0.01), while no significant difference was found for other vascular segments. The degree of stenosis was overestimated with QISS-MRA in 23 of 365 (6.3%) segments and underestimated in two of 365 (0.5%) segments. As compared to CE-MRA, QISS-MRA had a high sensitivity (98.6%), specificity (96%) as well as positive and negative predictive value (88.7 and 99.6%, respectively) for the detection of significant stenosis ({>=}50%). Conclusion: ECG-gated QISS-MRA is a promising imaging technique for reliable assessment of PAOD without the use of contrast material.

Nonenhanced ECG-gated quiescent-interval single-shot MRA (QISS-MRA) of the lower extremities: Comparison with contrast-enhanced MRA

International Nuclear Information System (INIS)

Klasen, J.; Blondin, D.; Schmitt, P.; Bi, X.; Sansone, R.; Wittsack, H.-J.; Kröpil, P.; Quentin, M.; Kuhlemann, J.; Miese, F.; Heiss, C.; Kelm, M.; Antoch, G.; Lanzman, R.S.

2012-01-01

Aim: To evaluate electrocardiogram (ECG)-gated quiescent-interval single-shot magnetic resonance angiography (QISS-MRA) for nonenhanced assessment of peripheral artery occlusive disease (PAOD) using contrast-enhanced MRA (CE-MRA) as the reference standard. Materials and methods: Twenty-seven patients (mean age 66.6 ± 10.8 years) with PAOD were included in the study. QISS-MRA and CE-MRA of the lower extremity were performed using a 1.5 T MR scanner. In each patient, subjective image quality and the degree of stenosis were evaluated on a four-point scale for 15 predefined arterial segments. Results: Twenty-five of the 27 patients were considered for analysis. Subjective image quality of QISS-MRA was significantly lower for the distal aorta, pelvic arteries, and femoral arteries as compared to CE-MRA (p < 0.01), while no significant difference was found for other vascular segments. The degree of stenosis was overestimated with QISS-MRA in 23 of 365 (6.3%) segments and underestimated in two of 365 (0.5%) segments. As compared to CE-MRA, QISS-MRA had a high sensitivity (98.6%), specificity (96%) as well as positive and negative predictive value (88.7 and 99.6%, respectively) for the detection of significant stenosis (≥50%). Conclusion: ECG-gated QISS-MRA is a promising imaging technique for reliable assessment of PAOD without the use of contrast material.

Subjective State, Blood Pressure, and Behavioral Control Changes Produced by an "Energy Shot"

Science.gov (United States)

Marczinski, Cecile A; Stamates, Amy L; Ossege, Julianne; Maloney, Sarah F; Bardgett, Mark E; Brown, Clifford J

2014-06-01

Background: Energy drinks and energy shots are popular consumer beverages that are advertised to increase feelings of alertness. Typically, these products include high levels of caffeine, a mild psychostimulant drug. The scientific evidence demonstrating the specific benefits of energy products to users in terms of subjective state and objective performance is surprisingly lacking. Moreover, there are rising health concerns associated with the use of these products. Therefore, the purpose of this study was to investigate the acute effects of a popular energy shot (5-Hour Energy ® ) on subjective and objective measures that were assessed hourly for 6 hours following consumption. Methods: Participants ( n =14) completed a three-session study where they received the energy shot, a placebo control, and no drink. Following dose administration, participants completed subjective Profile of Mood States ratings hourly for 6 hours. Participants also repeatedly completed a behavioral control task (the cued go/no-go task) and provided blood pressure and pulse rate readings at each hour. Results: Consumption of the energy shot did improve subjective state, as measured by increased ratings of vigor and decreased ratings of fatigue. However, the energy shot did not alter objective performance, which worsened over time. Importantly, the energy shot elevated both systolic and diastolic blood pressure. Conclusions: Consumption of one energy shot may only result in modest benefits to subjective state. Individuals with preexisting hypertension or other medical conditions should be cautious about using these new consumer products.

Efficient fiber-coupled single-photon sources based on quantum dots

DEFF Research Database (Denmark)

Daveau, Raphaël Sura

refrigeration with coupled quantum wells. Many photonic quantum information processing applications would benet from a highbrightness, ber-coupled source of triggered single photons. This thesis presents a study of such sources based on quantum dots coupled to unidirectional photonic-crystal waveguide devices.......6 %. This latter method opens a promising future for increasing the eciency and reliability of planar chip-based single-photon sources. Refrigeration of a solid-state system with light has potential applications for cooling small-scale electronic and photonic circuits. We show theoretically that two coupled...... semiconductor quantum wells are ecient cooling media because they support long-lived indirect electron-hole pairs. These pairs can be thermally excited to distinct higher-energy states with faster radiative recombination, thereby creating an ecient escape channel to remove thermal energy from the system. From...

Lower Extremity Muscle Activity During a Women's Overhand Lacrosse Shot

Directory of Open Access Journals (Sweden)

Millard Brianna M.

2014-07-01

Full Text Available The purpose of this study was to describe lower extremity muscle activity during the lacrosse shot. Participants (n=5 females, age 22±2 years, body height 162.6±15.2 cm, body mass 63.7±23.6 kg were free from injury and had at least one year of lacrosse experience. The lead leg was instrumented with electromyography (EMG leads to measure muscle activity of the rectus femoris (RF, biceps femoris (BF, tibialis anterior (TA, and medial gastrocnemius (GA. Participants completed five trials of a warm-up speed shot (Slow and a game speed shot (Fast. Video analysis was used to identify the discrete events defining specific movement phases. Full-wave rectified data were averaged per muscle per phase (Crank Back Minor, Crank Back Major, Stick Acceleration, Stick Deceleration. Average EMG per muscle was analyzed using a 4 (Phase x 2 (Speed ANOVA. BF was greater during Fast vs. Slow for all phases (p0.05. RF and GA were each influenced by the interaction of Phase and Speed (p<0.05 with GA being greater during Fast vs. Slow shots during all phases and RF greater during Crank Back Minor and Major as well as Stick Deceleration (p<0.05 but only tended to be greater during Stick Acceleration (p=0.076 for Fast vs. Slow. The greater muscle activity (BF, RF, GA during Fast vs. Slow shots may have been related to a faster approach speed and/or need to create a stiff lower extremity to allow for faster upper extremity movements.

Evaluation of cardiac function using multi-shot echo planar imaging

Energy Technology Data Exchange (ETDEWEB)

Nakanishi, Tadashi; Tanitame, Nobuko; Hata, Ryoichiro; Hirai, Nobuhiko; Ikeda, Midori; Ono, Chiaki; Fukuoka, Haruhito; Ito, Katsuhide [Hiroshima Univ. (Japan). School of Medicine

1998-01-01

In this study, we performed multi-shot echo planar imaging (8 shot, TR/TE/FL=55 ms/18 ms/60 degrees) and k-space segmented fast gradient echo sequence (8 views per segment, TR/TE/FL=9.9 ms/1.8 ms/30 degrees) to assess cardiac function in healthy volunteers. Transaxial sections of the entire heart were obtained with both sequences in ECG triggered, breath hold, and with a 256 x 128 matrix. Resulting temporal resolution was 55 ms for echo planar imaging, and 71 ms for k-space segmented fast gradient echo sequence, respectively. Ventricular volume and ejection fraction of both ventricles and left ventricular mass obtained with multi-shot echo planar imaging were assessed in comparison with k-space segmented fast gradient echo sequence. Measurements of left ventricular volume, ejection fraction and mass obtained with multi-shot echo planar imaging demonstrated close correlation with those obtained with k-space segmented fast gradient echo sequence. Right ventricular volumes obtained with echo planar imaging were significantly higher than those obtained with k-space segmented fast gradient echo sequence. This tendency is considered to be due to differing contrast between right ventricular myocardium and fat tissue observed with echo planar imaging relative to that observed with fast gradient echo sequence, because fat suppression is always performed in echo planar images. Multi-shot echo planar imaging can be a reliable tool for measurement of cardiac functional parameters, although wall motion analysis of the left ventricle requires higher temporal resolution and a short axial section. (K.H.)

Effects of Laser Peening, and Shot Peening, on Friction Stir Welding

Science.gov (United States)

Hatamleh, Omar; Hackel, Lloyd; Rankin, Jon; Truong, Chanh; Walter, Matt

2006-01-01

A viewgraph presentation describing the effects of laser peening and shot peening on friction stir welding is shown. The topics include: 1) Background; 2) Friction Stir Welding (FSW); 3) Microstructure; 4) Laser & Shot Peening; 5) Residual Stresses; 6) Tensile Behavior; 7) Fatigue Life & Surface Roughness; 8) Crack Growth; and 9) Benefits.

Muscular power, neuromuscular activation, and performance in shot put athletes at preseason and at competition period.

Science.gov (United States)

Kyriazis, Thomas A; Terzis, Gerasimos; Boudolos, Konstantinos; Georgiadis, Georgios

2009-09-01

The aim of this study was to investigate changes in shot put performance, muscular power, and neuromuscular activation of the lower extremities, between the preseason and the competition period, in skilled shot put athletes using the rotational technique. Shot put performance was assessed at the start of the pre-season period as well as after 12 weeks, at the competition period, in nine shot putters. Electromyographic (EMG) activity of the right vastus lateralis muscle was recorded during all shot put trials. Maximum squat strength (1RM) and mechanical parameters during the countermovement jump (CMJ) on a force platform were also determined at pre-season and at competition period. Shot put performance increased 4.7% (p phase was increased significantly (p training period. Shot put performance was significantly related with muscular power and takeoff velocity during the CMJ, at competition period (r = 0.66, p competition period.

Towards diffractive imaging with single pulses of FEL radiation. Dynamics within irradiatied samples and their influence on the analysis of imaging data

Energy Technology Data Exchange (ETDEWEB)

Wang, Fenglin

2010-08-15

3D single particle coherent diffraction imaging (CDI) of bioparticles (such as proteins, macromolecules and viruses) is one of the main possible applications of the new generation of light sources: free-electron lasers (FELs), which are now available at FLASH (Hamburg, Germany) and LCLS (Stanford, U.S.A.). The extremely bright and ultrashort FEL pulses potentially enable CDI to achieve high resolution down to subnanometer length scale. However, intense FEL pulses cause serious radiation damage in bioparticles, even during single shots, which may set the resolution limits for CDI with FELs. Currently, since the signal-to-noise ratio is very low for small biological particles, direct experimental study of radiation damage in the single particle imaging is fairly difficult. Single atomic (noble gas) clusters become good objects to reveal effects of radiation damage processes on CDI with FEL radiation. This thesis studies three aspects of the radiation damage problem, which are treated in three independent chapters: (1) Molecular Dynamics simulations to quantitively describe radiation damage processes within irradiated atomic clusters during single pulses; (2) reconstruction analysis of single-shot CDI diffraction patterns of atomic clusters, which may potentially help to understand the radiation damage occurring in biological samples; and (3) testing the effects of coating water layers in CDI, which is supposed to minimize the radiation damage in irradiated bioparticles. (orig.)

Evaluating laser-driven Bremsstrahlung radiation sources for imaging and analysis of nuclear waste packages

Energy Technology Data Exchange (ETDEWEB)

Jones, Christopher P., E-mail: cj0810@bristol.ac.uk [Interface Analysis Centre, HH Wills Physics Laboratory, Tyndall Avenue, Bristol BS8 1TL (United Kingdom); Brenner, Ceri M. [Central Laser Facility, STFC, Rutherford Appleton Laboratory, Didcot, Oxon OX11 0QX (United Kingdom); Stitt, Camilla A. [Interface Analysis Centre, HH Wills Physics Laboratory, Tyndall Avenue, Bristol BS8 1TL (United Kingdom); Armstrong, Chris; Rusby, Dean R. [Central Laser Facility, STFC, Rutherford Appleton Laboratory, Didcot, Oxon OX11 0QX (United Kingdom); Department of Physics, SUPA, University of Strathclyde, Glasgow G4 0NG (United Kingdom); Mirfayzi, Seyed R. [Centre for Plasma Physics, Queen' s University Belfast, Belfast BT7 1NN (United Kingdom); Wilson, Lucy A. [Central Laser Facility, STFC, Rutherford Appleton Laboratory, Didcot, Oxon OX11 0QX (United Kingdom); Alejo, Aarón; Ahmed, Hamad [Centre for Plasma Physics, Queen' s University Belfast, Belfast BT7 1NN (United Kingdom); Allott, Ric [Central Laser Facility, STFC, Rutherford Appleton Laboratory, Didcot, Oxon OX11 0QX (United Kingdom); Butler, Nicholas M.H. [Department of Physics, SUPA, University of Strathclyde, Glasgow G4 0NG (United Kingdom); Clarke, Robert J.; Haddock, David; Hernandez-Gomez, Cristina [Central Laser Facility, STFC, Rutherford Appleton Laboratory, Didcot, Oxon OX11 0QX (United Kingdom); Higginson, Adam [Department of Physics, SUPA, University of Strathclyde, Glasgow G4 0NG (United Kingdom); Murphy, Christopher [Department of Physics, University of York, York YO10 5DD (United Kingdom); Notley, Margaret [Central Laser Facility, STFC, Rutherford Appleton Laboratory, Didcot, Oxon OX11 0QX (United Kingdom); Paraskevoulakos, Charilaos [Interface Analysis Centre, HH Wills Physics Laboratory, Tyndall Avenue, Bristol BS8 1TL (United Kingdom); Jowsey, John [Ground Floor North B582, Sellafield Ltd, Seascale, Cumbria CA20 1PG (United Kingdom); and others

2016-11-15

Highlights: • X-ray generation was achieved via laser interaction with a tantalum thin foil target. • Picosecond X-ray pulse from a sub-mm spot generated high resolution images. • MeV X-ray emission is possible, permitting analysis of full scale waste containers. • In parallel neutron emission of 10{sup 7}–10{sup 9} neutrons per steradian per pulse was attained. • Development of a 10 Hz diode pumped laser system for waste monitoring is envisioned. - Abstract: A small scale sample nuclear waste package, consisting of a 28 mm diameter uranium penny encased in grout, was imaged by absorption contrast radiography using a single pulse exposure from an X-ray source driven by a high-power laser. The Vulcan laser was used to deliver a focused pulse of photons to a tantalum foil, in order to generate a bright burst of highly penetrating X-rays (with energy >500 keV), with a source size of <0.5 mm. BAS-TR and BAS-SR image plates were used for image capture, alongside a newly developed Thalium doped Caesium Iodide scintillator-based detector coupled to CCD chips. The uranium penny was clearly resolved to sub-mm accuracy over a 30 cm{sup 2} scan area from a single shot acquisition. In addition, neutron generation was demonstrated in situ with the X-ray beam, with a single shot, thus demonstrating the potential for multi-modal criticality testing of waste materials. This feasibility study successfully demonstrated non-destructive radiography of encapsulated, high density, nuclear material. With recent developments of high-power laser systems, to 10 Hz operation, a laser-driven multi-modal beamline for waste monitoring applications is envisioned.

Evaluating laser-driven Bremsstrahlung radiation sources for imaging and analysis of nuclear waste packages

International Nuclear Information System (INIS)

Jones, Christopher P.; Brenner, Ceri M.; Stitt, Camilla A.; Armstrong, Chris; Rusby, Dean R.; Mirfayzi, Seyed R.; Wilson, Lucy A.; Alejo, Aarón; Ahmed, Hamad; Allott, Ric; Butler, Nicholas M.H.; Clarke, Robert J.; Haddock, David; Hernandez-Gomez, Cristina; Higginson, Adam; Murphy, Christopher; Notley, Margaret; Paraskevoulakos, Charilaos; Jowsey, John

2016-01-01

Highlights: • X-ray generation was achieved via laser interaction with a tantalum thin foil target. • Picosecond X-ray pulse from a sub-mm spot generated high resolution images. • MeV X-ray emission is possible, permitting analysis of full scale waste containers. • In parallel neutron emission of 10"7–10"9 neutrons per steradian per pulse was attained. • Development of a 10 Hz diode pumped laser system for waste monitoring is envisioned. - Abstract: A small scale sample nuclear waste package, consisting of a 28 mm diameter uranium penny encased in grout, was imaged by absorption contrast radiography using a single pulse exposure from an X-ray source driven by a high-power laser. The Vulcan laser was used to deliver a focused pulse of photons to a tantalum foil, in order to generate a bright burst of highly penetrating X-rays (with energy >500 keV), with a source size of <0.5 mm. BAS-TR and BAS-SR image plates were used for image capture, alongside a newly developed Thalium doped Caesium Iodide scintillator-based detector coupled to CCD chips. The uranium penny was clearly resolved to sub-mm accuracy over a 30 cm"2 scan area from a single shot acquisition. In addition, neutron generation was demonstrated in situ with the X-ray beam, with a single shot, thus demonstrating the potential for multi-modal criticality testing of waste materials. This feasibility study successfully demonstrated non-destructive radiography of encapsulated, high density, nuclear material. With recent developments of high-power laser systems, to 10 Hz operation, a laser-driven multi-modal beamline for waste monitoring applications is envisioned.

Accuracy of Dual-Energy Virtual Monochromatic CT Numbers: Comparison between the Single-Source Projection-Based and Dual-Source Image-Based Methods.

Science.gov (United States)

Ueguchi, Takashi; Ogihara, Ryota; Yamada, Sachiko

2018-03-21

To investigate the accuracy of dual-energy virtual monochromatic computed tomography (CT) numbers obtained by two typical hardware and software implementations: the single-source projection-based method and the dual-source image-based method. A phantom with different tissue equivalent inserts was scanned with both single-source and dual-source scanners. A fast kVp-switching feature was used on the single-source scanner, whereas a tin filter was used on the dual-source scanner. Virtual monochromatic CT images of the phantom at energy levels of 60, 100, and 140 keV were obtained by both projection-based (on the single-source scanner) and image-based (on the dual-source scanner) methods. The accuracy of virtual monochromatic CT numbers for all inserts was assessed by comparing measured values to their corresponding true values. Linear regression analysis was performed to evaluate the dependency of measured CT numbers on tissue attenuation, method, and their interaction. Root mean square values of systematic error over all inserts at 60, 100, and 140 keV were approximately 53, 21, and 29 Hounsfield unit (HU) with the single-source projection-based method, and 46, 7, and 6 HU with the dual-source image-based method, respectively. Linear regression analysis revealed that the interaction between the attenuation and the method had a statistically significant effect on the measured CT numbers at 100 and 140 keV. There were attenuation-, method-, and energy level-dependent systematic errors in the measured virtual monochromatic CT numbers. CT number reproducibility was comparable between the two scanners, and CT numbers had better accuracy with the dual-source image-based method at 100 and 140 keV. Copyright © 2018 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.

Room-Temperature Single-Photon Source for Secure Quantum Communication

Data.gov (United States)

National Aeronautics and Space Administration — We are asking for four years of support for PhD student Justin Winkler's work on a research project entitled "Room temperature single photon source for secure...

Effect of shot peening process on fatigue behavior of an alloyed austempered ductile iron

Directory of Open Access Journals (Sweden)

Amir Sadighzadeh Benam

2011-08-01

Full Text Available Shot peening is one of the most common surface treatments to improve the fatigue behavior of metallic parts. In this study the effect of shot peening process on the fatigue behavior of an alloyed austempered ductile iron (ADI has been studied. Austempering heat treatment consisted of austenitizing at 875℃ for 90 min followed by austempering at three different temperatures of 320, 365 and 400℃. Rotating-bending fatigue test was carried out on samples after shot peening by 0.4 – 0.6 mm shots. XRD and SEM analysis, micro hardness and roughness tests were carried out to study the fatigue behavior of the samples. Results indicate that the fatigue strengths of samples austempered at 320, 365 and 400℃ are increased by 27.3%, 33.3% and 48.4%, respectively, after shot peening process.

On the residual stress modeling of shot-peened AISI 4340 steel: finite element and response surface methods

Science.gov (United States)

Asgari, Ali; Dehestani, Pouya; Poruraminaie, Iman

2018-02-01

Shot peening is a well-known process in applying the residual stress on the surface of industrial parts. The induced residual stress improves fatigue life. In this study, the effects of shot peening parameters such as shot diameter, shot speed, friction coefficient, and the number of impacts on the applied residual stress will be evaluated. To assess these parameters effect, firstly the shot peening process has been simulated by finite element method. Then, effects of the process parameters on the residual stress have been evaluated by response surface method as a statistical approach. Finally, a strong model is presented to predict the maximum residual stress induced by shot peening process in AISI 4340 steel. Also, the optimum parameters for the maximum residual stress are achieved. The results indicate that effect of shot diameter on the induced residual stress is increased by increasing the shot speed. Also, enhancing the friction coefficient magnitude always cannot lead to increase in the residual stress.

Shot Noise in Negative-Differential-Conductance Devices

National Research Council Canada - National Science Library

Song, W

2003-01-01

The authors have compared the shot-noise properties at T = 4.2 K of a double-barrier resonant-tunneling diode and a superlattice tunnel diode, both of which exhibit negative differential-conductance (NDC...

Residual stress and microstructural behaviour of a shot peened steel in fatigue. An X-ray diffraction study

Energy Technology Data Exchange (ETDEWEB)

Bergstroem, J.

1986-01-01

The surface residual stress behaviour during fatigue of the quenched and tempered medium strength low-alloyed steel SS 2244-05, equivalent to AISI 4140, has been investigated. Notched specimens of shot peened and ground surface conditions were used. The residual stresses were measured by the X-ray diffraction sin/sup 2/psi-method at intervals in the fatigue tests. Fatigue testing was performed with constant load amplitude at nominal pull-push and pull-pull cycling. The effects of peak-load and variable amplitude were also examined. It was found that the residual stress relaxation could be linked to a total mean stress relaxation towards zero, to an extent which is ruled by a softening criteria. Fatigue test data of the shot peened and ground surface conditions are also given. An X-ray diffraction line broadening analysis was undertaken to examine the microstructural behaviour due to fatigue loading and its correlation to the residual stress behaviour. Single-peak analysis with a Voigt-function method was used to estimate the microstructural parameters, domain size and microstrain. Multiple-peak analysis according to the Warren-Averbach method was used to verify the single-peak analysis. The dislocation density was found to decrease depending on the load amplitude, while the dislocation arrangement follows a pattern depending on yield history.

Shot peening of doel 3 plant

International Nuclear Information System (INIS)

Slama, G.; Sort, M.

1985-12-01

The process implementation for DOEL consisted in: developing tooling and test procedures for an industrial application including ALARA considerations; qualifying process, tooling and procedures using representative conditions (full size mock-up, of steam generator channel head and associated working area); Establishing the reliability of tooling and procedures to comply permanently with the required criteria (chiefly Almen Intensity); and training and qualifying personnel. A variety of tests were performed by FRAMATOME and BELGATOM to qualify the process and characterize its effects on both inside and outside diameters of the tubes. These are: Mg Cl 2 ; 10% caustic tests at high temperature and pressure; tetrathionate; strain gauges and X rays stresses measurements; effects on precracked tubes; Leak tests after shot peening. The operation was performed at Doel in July 1985. Laboratory tests performed on mockups by FRAMATOME and BELGATOM could demonstrate that on tubes without cracks no difference was found between Eddy current signals from tubes shot-peened or not

Improved design and durability of aluminum die casting horizontal shot sleeves

Science.gov (United States)

Birceanu, Sebastian

The design and performance of shot sleeves is critical in meeting the engineering requirements of aluminum die cast parts. Improvement in shot sleeve materials have a major impact on dimensional stability, reproducibility and quality of the product. This investigation was undertaken in order to improve the life of aluminum die casting horizontal shot sleeves. Preliminary pin tests were run to evaluate the soldering, wash-out and thermal fatigue behavior of commercially available materials and coatings. An experimental rig was designed and constructed for shot sleeve configuration evaluation. Fabrication and testing of experimental shot sleeves was based upon preliminary results and manufacturing costs. Three shot sleeve designs and materials were compared to a reference nitrided H13 sleeve. Nitrided H13 is the preferred material for aluminum die casting shot sleeves because of wear resistance, strength and relative good soldering and wash-out resistance. The study was directed towards damage evaluation on the area under the pouring hole. This area is the most susceptible to damage because of high temperatures and impingement of molten aluminum. The results of this study showed that tungsten and molybdenum had the least amount of soldering and wash-out damage, and the best thermal fatigue resistance. Low solubility in molten aluminum and stability of intermetallic layers are main factors that determine the soldering and wash-out behavior. Thermal conductivity and thermal expansion coefficient directly influence thermal fatigue behavior. TiAlN nanolayered coating was chosen as the material with the best damage resistance among several commercial PVD coatings, because of relatively large thickness and simple deposition conditions. The results show that molybdenum thermal sprayed coating provided the best protection against damage under the pouring hole. Improved bonding is however required for life extension of the coating. TiAlN PVD coating applied on H13 nitrided

Intercommunications of indexes of speed and power qualities of sportsmen single combat on the stage of the specialized base preparation

Directory of Open Access Journals (Sweden)

A.O. Nykytenko

2013-01-01

Full Text Available The purpose of work is a study of interdependence between indexes specially-preparatory and general preparatory exercises of sportsmen (boxing, sporting hand-to-hand fight hopak, fencing. 42 sportsmen took part in researches. Statistical reliable intercommunications are set: a indexes of force of shots by hands with the indexes of rate of single movement; b indexes of force of shots by feet with indexes from maximal force of muscles (tractive forces; c indexes of speed of shots by hands (pricking with the indexes of distance of shove of balls by mass 300 gramme; d indexes of speed of movement a step in a battle bar with indexes: speeds of shots by hands (pricking; e indexes of frequency of shots of boxers and sportsmen hand-to-hand fight hopak with the indexes of frequency of movement (manoeuvring on feet. Facilities which it is expedient to apply in the training process of single combats on this stage of long-term preparation are certain.

Microscopic analysis of effect of shot peening on corrosion fatigue behavior of aluminum alloy

International Nuclear Information System (INIS)

Kim, Jong Cheon; Cheong, Seong Kyun

2012-01-01

The object of this study considers corrosion fatigue improvement of 7075-T6 aluminum by using shot peening treatment on 3.5% NaCl solution at room temperature. Aluminum alloy is generally used in aerospace structural components because of the light weight and high strength characteristics. Many studies have shown that an aluminum alloy can be approximately 50% lighter than other materials. Mostly, corrosion leads to earlier fatigue crack propagation under tensile conditions and severely reduces the life of structures. Therefore, the technique to improve material resistance to corrosion fatigue is required. Shot peening technology is widely used to improve fatigue life and other mechanical properties by induced compressive residual stress. Even the roughness of treated surface causes pitting corrosion, the compressive residual stress, which is induced under the surface layer of material by shot peening, suppersses the corrosion and increases the corrosion resistance. The experimental results for shot peened specimens were compared with previous work for non treated aluminum alloy. The results show that the shot peening treatment affects the corrosion fatigue improvement of aluminum alloys and the induced compressive residual stress by shot peening treatment improves the resistance to corrosion fatigue

Microscopic analysis of effect of shot peening on corrosion fatigue behavior of aluminum alloy

Energy Technology Data Exchange (ETDEWEB)

Kim, Jong Cheon; Cheong, Seong Kyun [Seoul Nat' l Univ. of Science and Technology, Seoul (Korea, Republic of)

2012-11-15

The object of this study considers corrosion fatigue improvement of 7075-T6 aluminum by using shot peening treatment on 3.5% NaCl solution at room temperature. Aluminum alloy is generally used in aerospace structural components because of the light weight and high strength characteristics. Many studies have shown that an aluminum alloy can be approximately 50% lighter than other materials. Mostly, corrosion leads to earlier fatigue crack propagation under tensile conditions and severely reduces the life of structures. Therefore, the technique to improve material resistance to corrosion fatigue is required. Shot peening technology is widely used to improve fatigue life and other mechanical properties by induced compressive residual stress. Even the roughness of treated surface causes pitting corrosion, the compressive residual stress, which is induced under the surface layer of material by shot peening, suppersses the corrosion and increases the corrosion resistance. The experimental results for shot peened specimens were compared with previous work for non treated aluminum alloy. The results show that the shot peening treatment affects the corrosion fatigue improvement of aluminum alloys and the induced compressive residual stress by shot peening treatment improves the resistance to corrosion fatigue.

Utility of single shot fast spin echo technique in evaluating pancreaticobiliary diseases: T2-weighted image and magnetic resonance cholangiopancreatography

International Nuclear Information System (INIS)

Choi, Byoung Wook; Kim, Myeong Jin; Chung, Jae Bok; Ko, Heung Kyu; Kim, Dong Joon; Kim, Joo Hee; Chung, Jae Joon; Yoo, Hyung Sik; Lee, Jong Tae

1999-01-01

To evaluate the accuracy of T2-weighted imaging an MR cholangiopancreatography using the single shot fast spin-echo technique for evaluating pancreaticobiliary disease. Between March and July 1997, axial and coronal T2-weighted images(TE: 80-200 msec) and MR cholangiopancreatograms (TE: 800-1200 msec) were obtained in two ways [single slab (thickness: 30-50 mm) and multislice acquisition under chemical fat saturation] using SSFSE pulse sequencing in 131 cases of suspected pancreati-cobiliary disease. The accuracy of SSFSE MR imaging was assessed in 89 lesions of 74 patients [male, 48; female, 26; age range, 30-86 (mean, 59) years] confirmed surgicopathologically (50 lesions in 39 patients) and clinically (39 lesions in 35 patients). Two radiologists reviewed the MR images and diagnosis was determined by consensus. Correct diagnosis was confirmed in 84 of 89 lesions (94%). Seven lesions were falsely interpreted, false positive and false negative results accounting for two and five cases, respectively. Two pancreatic cancers were misdiagnosed as pancreatitis and a cancer of the proximal common bile duct(CBD) was interpreted as a distal CBD cancer. The sensitivity of SSFSE MR imaging for malignancy was 93 %. One CBD stone revealed by endoscopic retrograde cholangiopancreatography (ERCP) was not detected on MR images. In contrast, a stone in the CBD seen on MR images was not apparent on subsequent ERCP. Sensitivity and specificity for calculous disease were 96% and 99.7%, respectively. A benign stricture of the ampulla of Vater was falsely interpreted as normal, and correct diagnosis was possible in two falsely diagnosed cases when MR images were reviewed retrospectively. The combination of T2-weighted and cholangiographic images using SSFSE is an accurate method for diagnosing pancreatcobiliary diseases

Evaluation of the 1Shot Phantom dedicated to the mammography system using FCR

International Nuclear Information System (INIS)

Nagashima, Chieko; Uchiyama, Nachiko; Moriyama, Noriyuki; Nagata, Mio; Kobayashi, Hiroyuki; Sankoda, Katsuhiro; Saotome, Shigeru; Tagi, Masahiro; Kusunoki, Tetsurou

2009-01-01

Currently daily quality control (QC) tests for mammography systems are generally evaluated by using visual analysis phantoms, which of course means subjective measurement. In our study, however, we evaluated a novel digital phantom, the 1Shot Phantom M plus (1Shot Phantom), together with automatic analysis software dedicated for mammography systems using Fuji computed radiography (FCR). The digital phantom enables objective evaluation by providing for actual physical measurement rather than subjective visual assessment. We measured contrast to noise ratio (CNR), image receptor homogeneity, missed tissue at chest wall side, modulation transfer function (MTF), and geometric distortion utilizing the 1Shot Phantom. We then compared the values obtained using the 1Shot Phantom with values obtained from the European guidelines and International Electrotechnical Commission (IEC) standards. In addition, we evaluated the convenience of using the digital phantom. The values utilizing the 1Shot Phantom and those from the European guidelines and IEC standards were consistent, but the QC tests for the European guidelines and IEC standards methods took about six hours while the same QC tests using the 1Shot Phantom took 10 minutes or less including exposure of the phantom image, measurement, and analysis. In conclusion, the digital phantom and dedicated software proved very useful and produced improved analysis for mammography systems using FCR in clinical daily QC testing because of their objectivity and substantial time-saving convenience. (author)

Propagation characteristics of audible noise generated by single corona source under positive DC voltage

Directory of Open Access Journals (Sweden)

Xuebao Li

2017-10-01

Full Text Available The directivity and lateral profile of corona-generated audible noise (AN from a single corona source are measured through experiments carried out in the semi-anechoic laboratory. The experimental results show that the waveform of corona-generated AN consists of a series of random sound pressure pulses whose pulse amplitudes decrease with the increase of measurement distance. A single corona source can be regarded as a non-directional AN source, and the A-weighted SPL (sound pressure level decreases 6 dB(A as doubling the measurement distance. Then, qualitative explanations for the rationality of treating the single corona source as a point source are given on the basis of the Ingard’s theory for sound generation in corona discharge. Furthermore, we take into consideration of the ground reflection and the air attenuation to reconstruct the propagation features of AN from the single corona source. The calculated results agree with the measurement well, which validates the propagation model. Finally, the influence of the ground reflection on the SPL is presented in the paper.

Sub-megahertz linewidth single photon source

Directory of Open Access Journals (Sweden)

Markus Rambach

2016-12-01

Full Text Available We report 100% duty cycle generation of sub-MHz single photon pairs at the rubidium D1 line using cavity-enhanced spontaneous parametric downconversion. The temporal intensity cross correlation function exhibits a bandwidth of 666±16 kHz for the single photons, an order of magnitude below the natural linewidth of the target transition. A half-wave plate inside our cavity helps to achieve triple resonance between pump, signal, and idler photon, reducing the bandwidth and simplifying the locking scheme. Additionally, stabilisation of the cavity to the pump frequency enables the 100% duty cycle. The quantum nature of the source is confirmed by the idler-triggered second-order autocorrelation function at τ=0 to be gs,s(2(0= 0.016±0.002 for a heralding rate of 5 kHz. The generated photons are well-suited for storage in quantum memory schemes with sub-natural linewidths, such as gradient echo memories.

Stable single-photon source in the near infrared

International Nuclear Information System (INIS)

Gaebel, T; Popa, I; Gruber, A; Domhan, M; Jelezko, F; Wrachtrup, J

2004-01-01

Owing to their unsurpassed photostability, defects in solids may be ideal candidates for single-photon sources. Here we report on generation of single photons by optical excitation of a yet unexplored defect in diamond, the nickel-nitrogen complex (NE8) centre. The most striking feature of the defect is its emission bandwidth of 1.2 nm at room temperature. The emission wavelength of the defect is around 800 nm, which is suitable for telecom fibres. In addition, in this spectral region little background light from the diamond bulk material is detected. Consequently, a high contrast in antibunching measurements is achieved

A Shot Parameter Specification Subsystem for automated control of PBFA [Particle Beam Fusion Accelerator] II accelerator shots

International Nuclear Information System (INIS)

Spiller, J.L.

1987-01-01

The Shot Parameter Specification Subsystem (SPSS) is an integral part of the automatic control system developed for the Particle Beam Fusion Accelerator II (PBFA II) by the Control Monitor (C/M) Software Development Team. This system has been designed to fully utilize the accelerator by tailoring shot parameters to the needs of the experimenters. The SPSS is the key to this flexibility. Automatic systems will be required on many pulsed power machines for the fastest turnaround, the highest reliability, and most cost effective operation. These systems will require the flexibility and the ease of use that is part of the SPSS. The PBFA II control system has proved to be an effective modular system, flexible enough to meet the demands of both the fast track construction of PBFA II and the control needs of Hermes III at the Simulation Technology Laboratory. This system is expected to meet the demands of most future machine changes

Serotonin exerting protection of serum lipid pattern in male albino rat subjected to shot or intermittent whole body gamma irradiation

International Nuclear Information System (INIS)

El-Dighidy, E.A.M.; El-Kady, M.H.R.

1995-01-01

Certain cancer patients are subjected to varying levels of intermittent radiation delivered in certain cases as whole body exposure. Effective control of many haematological complications built up during radiation treatment would necessarily contribute to up-grading of cancer radiotherapy. In the present study, the effect of either shot or intermittent whole body gamma irradiation at cumulative dose levels up to 6 and 10 Gy, have been evaluated on the levels of total lipids and lipid fractions in blood serum of male albino rats. The pharmacological role of serotonin and its potential radioprotective capacity have been assessed on the serum lipid pattern. The results indicated generally significant increases in the levels of blood lipid fractions especially HDL-cholesterol. On the other hand, the level of LDL-cholesterol recorded a significant decrease on the third day post either shot or cumulative dose levels at 6 or 10 Gy and also post 4 successive doses of serotonin administration. The only exceptions were recorded in the case of LDL-cholesterol post administration of single dose of serotonin and serotonin prior to shot dose levels of 6 or 10 Gy. 2 tabs

Single-shot ultrabroadband two-dimensional electronic spectroscopy of the light-harvesting complex LH2.

Science.gov (United States)

Harel, Elad; Long, Phillip D; Engel, Gregory S

2011-05-01

Here we present two-dimensional (2D) electronic spectra of the light-harvesting complex LH2 from purple bacteria using coherent pulses with bandwidth of over 100 nm FWHM. This broadband excitation and detection has allowed the simultaneous capture of both the B800 and B850 bands using a single light source. We demonstrate that one laser pulse is sufficient to capture the entire 2D electronic spectrum with a high signal-to-noise ratio. At a waiting time of 800 fs, we observe population transfer from the B800 to B850 band as manifested by a prominent cross peak. These results will enable observation of the dynamics of biological systems across both ultrafast (1 ms) timescales simultaneously.

Test to Extract Soil Properties Using the Seismic HammerTM Active Seismic Source

Energy Technology Data Exchange (ETDEWEB)

Lee, Rebekah F. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Abbott, Robert E. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

2017-08-01

Geologic material properties are necessary parameters for ground motion modeling and are difficult and expensive to obtain via traditional methods. Alternative methods to estimate soil properties require a measurement of the ground's response to a force. A possible method of obtaining these measurements is active-source seismic surveys, but measurements of the ground response at the source must also be available. The potential of seismic sources to obtain soil properties is limited, however, by the repeatability of the source. Explosives, and hammer surveys are not repeatable because of variable ground coupling or swing strength. On the other hand, the Seismic Hammer TM (SH) is consistent in the amount of energy it inputs into the ground. In addition, it leaves large physical depressions as a result of ground compaction. The volume of ground compaction varies by location. Here, we hypothesize that physical depressions left in the earth by the SH correlate to energy recorded by nearby geophones, and therefore are a measurement of soil physical properties. Using measurements of the volume of shot holes, we compare the spatial distribution of the volume of ground compacted between the different shot locations. We then examine energy recorded by the nearest 50 geophones and compare the change in amplitude across hits at the same location. Finally, we use the percent difference between the energy recorded by the first and later hits at a location to test for a correlation to the volume of the shot depressions. We find that: * Ground compaction at the shot-depression does cluster geographically, but does not correlate to known surface features. * Energy recorded by nearby geophones reflects ground refusal after several hits. * There is no correlation to shot volume and changes in energy at particular shot locations. Deeper material properties (i.e. below the depth of surface compaction) may be contributing to the changes in energy propagation. * Without further

Pumped shot noise in adiabatically modulated graphene-based double-barrier structures.

Science.gov (United States)

Zhu, Rui; Lai, Maoli

2011-11-16

Quantum pumping processes are accompanied by considerable quantum noise. Based on the scattering approach, we investigated the pumped shot noise properties in adiabatically modulated graphene-based double-barrier structures. It is found that compared with the Poisson processes, the pumped shot noise is dramatically enhanced where the dc pumped current changes flow direction, which demonstrates the effect of the Klein paradox.

Pumped shot noise in adiabatically modulated graphene-based double-barrier structures

Science.gov (United States)

Zhu, Rui; Lai, Maoli

2011-11-01

Quantum pumping processes are accompanied by considerable quantum noise. Based on the scattering approach, we investigated the pumped shot noise properties in adiabatically modulated graphene-based double-barrier structures. It is found that compared with the Poisson processes, the pumped shot noise is dramatically enhanced where the dc pumped current changes flow direction, which demonstrates the effect of the Klein paradox.

Shot noise of a quantum shuttle

DEFF Research Database (Denmark)

Novotny, Tomas; Donarini, Andrea; Flindt, Christian

2004-01-01

We formulate a theory for shot noise in quantum nanoelectromechanical systems. As a specific example, the theory is applied to a quantum shuttle, and the zero-frequency noise, measured by the Fano factor F, is computed. F reaches very low values (Fsimilar or equal to10(-2)) in the shuttling regim...

Kinematic Differences between Set- and Jump-Shot Motions in Basketball

OpenAIRE

Hiroki Okubo; Mont Hubbard

2018-01-01

Shooting arm motions at release in one-hand set and jump basketball shots have been analyzed using a kinematic model. Set and jump shots are classified by the vertical velocity and acceleration of the shooter’s shooting-side shoulder at release. The two-dimensional three-segment model includes the vertical shooting-side shoulder velocity and acceleration. Numerical simulation investigates the effect of shoulder motion. Release backspin angular velocity can be described as a function of the ve...

On the Path to SunShot - Executive Summary

Energy Technology Data Exchange (ETDEWEB)

None, None

2016-05-01

The halfway mark of the SunShot Initiative’s 2020 target date is a good time to take stock: How much progress has been made? What have we learned? What barriers and opportunities must still be addressed to ensure that solar technologies achieve cost parity in 2020 and realize their full potential in the decades beyond? To answer these questions, the Solar Energy Technology Office launched the On the Path to SunShot series in early 2015 in collaboration with the National Renewable Energy Laboratory (NREL) and with contributions from Lawrence Berkeley National Laboratory (LBNL), Sandia National Laboratories (SNL), and Argonne National Laboratory (ANL). The reports focus on the areas of technology development, systems integration, and market enablers.

The effect of shot peening on notched low cycle fatigue

International Nuclear Information System (INIS)

Soady, K.A.; Mellor, B.G.; Shackleton, J.; Morris, A.; Reed, P.A.S.

2011-01-01

Highlights: → Shot peening improves notched component three point bend low cycle fatigue life. → Notch shape does not affect the efficacy of the peening process. → Strain hardening and residual stress effects need separate consideration. → Loading direction residual stresses do not relax under bend load. - Abstract: The improvement in low cycle fatigue life created by shot peening ferritic heat resistant steel was investigated in components of varying geometries based on those found in conventional power station steam turbine blades. It was found that the shape of the component did not affect the efficacy of the shot peening process, which was found to be beneficial even under the high stress amplitude three point bend loads applied. Furthermore, by varying the shot peening process parameters and considering fatigue life it has been shown that the three surface effects of shot peening; roughening, strain hardening and the generation of a compressive residual stress field must be included in remnant life models as physically separate entities. The compressive residual stress field during plane bending low cycle fatigue has been experimentally determined using X-ray diffraction at varying life fractions and found to be retained in a direction parallel to that of loading and to only relax to 80% of its original magnitude in a direction orthogonal to loading. This result, which contributes to the retention of fatigue life improvement in low cycle fatigue conditions, has been discussed in light of the specific stress distribution applied to the components. The ultimate aim of the research is to apply these results in a life assessment methodology which can be used to justify a reduction in the length of scheduled plant overhauls. This will result in significant cost savings for the generating utility.

Shot Boundary Detection in Soccer Video using Twin-comparison Algorithm and Dominant Color Region

Directory of Open Access Journals (Sweden)

Matko Šarić

2008-06-01

Full Text Available The first step in generic video processing is temporal segmentation, i.e. shot boundary detection. Camera shot transitions can be either abrupt (e.g. cuts or gradual (e.g. fades, dissolves, wipes. Sports video is one of the most challenging domains for robust shot boundary detection. We proposed a shot boundary detection algorithm for soccer video based on the twin-comparison method and the absolute difference between frames in their ratios of dominant colored pixels to total number of pixels. With this approach the detection of gradual transitions is improved by decreasing the number of false positives caused by some camera operations. We also compared performances of our algorithm and the standard twin-comparison method.

Transfer of mechanical energy during the shot put

Directory of Open Access Journals (Sweden)

Błażkiewicz Michalina

2016-09-01

Full Text Available The aim of this study was to analyse transfer of mechanical energy between body segments during the glide shot put. A group of eight elite throwers from the Polish National Team was analysed in the study. Motion analysis of each throw was recorded using an optoelectronic Vicon system composed of nine infrared camcorders and Kistler force plates. The power and energy were computed for the phase of final acceleration of the glide shot put. The data were normalized with respect to time using the algorithm of the fifth order spline and their values were interpolated with respect to the percentage of total time, assuming that the time of the final weight acceleration movement was different for each putter. Statistically significant transfer was found in the study group between the following segments: Right Knee – Right Hip (p = 0.0035, Left Hip - Torso (p = 0.0201, Torso – Right Shoulder (p = 0.0122 and Right Elbow – Right Wrist (p = 0.0001. Furthermore, the results of cluster analysis showed that the kinetic chain used during the final shot acceleration movement had two different models. Differences between the groups were revealed mainly in the energy generated by the hips and trunk.

Feature Selection Methods for Zero-Shot Learning of Neural Activity

Directory of Open Access Journals (Sweden)

Carlos A. Caceres

2017-06-01

Full Text Available Dimensionality poses a serious challenge when making predictions from human neuroimaging data. Across imaging modalities, large pools of potential neural features (e.g., responses from particular voxels, electrodes, and temporal windows have to be related to typically limited sets of stimuli and samples. In recent years, zero-shot prediction models have been introduced for mapping between neural signals and semantic attributes, which allows for classification of stimulus classes not explicitly included in the training set. While choices about feature selection can have a substantial impact when closed-set accuracy, open-set robustness, and runtime are competing design objectives, no systematic study of feature selection for these models has been reported. Instead, a relatively straightforward feature stability approach has been adopted and successfully applied across models and imaging modalities. To characterize the tradeoffs in feature selection for zero-shot learning, we compared correlation-based stability to several other feature selection techniques on comparable data sets from two distinct imaging modalities: functional Magnetic Resonance Imaging and Electrocorticography. While most of the feature selection methods resulted in similar zero-shot prediction accuracies and spatial/spectral patterns of selected features, there was one exception; A novel feature/attribute correlation approach was able to achieve those accuracies with far fewer features, suggesting the potential for simpler prediction models that yield high zero-shot classification accuracy.

Localizing gravitational wave sources with single-baseline atom interferometers

Science.gov (United States)

Graham, Peter W.; Jung, Sunghoon

2018-02-01

Localizing sources on the sky is crucial for realizing the full potential of gravitational waves for astronomy, astrophysics, and cosmology. We show that the midfrequency band, roughly 0.03 to 10 Hz, has significant potential for angular localization. The angular location is measured through the changing Doppler shift as the detector orbits the Sun. This band maximizes the effect since these are the highest frequencies in which sources live for several months. Atom interferometer detectors can observe in the midfrequency band, and even with just a single baseline they can exploit this effect for sensitive angular localization. The single-baseline orbits around the Earth and the Sun, causing it to reorient and change position significantly during the lifetime of the source, and making it similar to having multiple baselines/detectors. For example, atomic detectors could predict the location of upcoming black hole or neutron star merger events with sufficient accuracy to allow optical and other electromagnetic telescopes to observe these events simultaneously. Thus, midband atomic detectors are complementary to other gravitational wave detectors and will help complete the observation of a broad range of the gravitational spectrum.

Berry phase and shot noise for spin-polarized and entangled electrons

International Nuclear Information System (INIS)

Wang Pei; Tang Weihua; Lu Dinghui; Jiang Lixia; Zhao Xuean

2007-01-01

Shot noise for entangled and spin-polarized states in a four-probe geometric setup has been studied by adding two rotating magnetic fields in an incoming channel. Our results show that the noise power oscillates as the magnetic fields vary. The singlet, entangled triplet and polarized states can be distinguished by adjusting the magnetic fields. The Berry phase can be derived by measuring the shot noise power

Effects of shot peening on the residual stress of welded SS400 steel

International Nuclear Information System (INIS)

Lee, Jong Man; Kim, Tae Hyung; Cheong, Seong Kyun; Lee, Seung Ho

2002-01-01

The fatigue life of structures is usually determined by welding zone. The tensile residual stress, which is induced by welding, reduces the fatigue life and fatigue strength of welded structures. If we remove the tensile residual stress or induce the compressive residual stress, the fatigue life of welded structures will be improved. The change of hardness and compressive residual stress of welded zone after shot peening was investigated in this paper. The results show that the hardness was increased by shot peening. The residual stress was reduced by shot peening

A High-Power Laser-Driven Source of Sub-nanosecond Soft X-Ray Pulses for Single-Shot Radiobiology Experiments

Czech Academy of Sciences Publication Activity Database

Davídková, Marie; Juha, Libor; Bittner, Michal; Koptyaev, Sergey; Hájková, Věra; Krása, Josef; Pfeifer, Miroslav; Štísová, Viktorie; Bartnik, A.; Fiedorowicz, H.; Mikolajczyk, J.; Ryc, L.; Pína, L.; Horváth, M.; Babánková, Dagmar; Cihelka, Jaroslav; Civiš, Svatopluk

2007-01-01

Roč. 168, č. 3 (2007), s. 382-387 ISSN 0033-7587 R&D Projects: GA ČR GA202/05/2316; GA MŠk(CZ) LC528; GA MŠk 1P04LA235; GA MŠk LC510 Institutional research plan: CEZ:AV0Z10480505; CEZ:AV0Z10100523; CEZ:AV0Z20430508; CEZ:AV0Z40400503 Keywords : soft X-rays * radiation damage to DNA * laser-driven source Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 2.599, year: 2007

Demonstration of acoustic source localization in air using single pixel compressive imaging

Science.gov (United States)

Rogers, Jeffrey S.; Rohde, Charles A.; Guild, Matthew D.; Naify, Christina J.; Martin, Theodore P.; Orris, Gregory J.

2017-12-01

Acoustic source localization often relies on large sensor arrays that can be electronically complex and have large data storage requirements to process element level data. Recently, the concept of a single-pixel-imager has garnered interest in the electromagnetics literature due to its ability to form high quality images with a single receiver paired with shaped aperture screens that allow for the collection of spatially orthogonal measurements. Here, we present a method for creating an acoustic analog to the single-pixel-imager found in electromagnetics for the purpose of source localization. Additionally, diffraction is considered to account for screen openings comparable to the acoustic wavelength. A diffraction model is presented and incorporated into the single pixel framework. In this paper, we explore the possibility of applying single pixel localization to acoustic measurements. The method is experimentally validated with laboratory measurements made in an air waveguide.

Equilibrium and shot noise in mesoscopic systems

Energy Technology Data Exchange (ETDEWEB)

Martin, T.

1994-10-01

Within the last decade, there has been a resurgence of interest in the study of noise in Mesoscopic devices, both experimentally and theoretically. Noise in solid state devices can have different origins: there is 1/f noise, which is believed to arise from fluctuations in the resistance of the sample due to the motion of impurities. On top of this contribution is a frequency independent component associated with the stochastic nature of electron transport, which will be the focus of this paper. If the sample considered is small enough that dephasing and inelastic effects can be neglected, equilibrium (thermal) and excess noise can be completely described in terms of the elastic scattering properties of the sample. As mentioned above, noise arises as a consequence of random processes governing the transport of electrons. Here, there are two sources of randomness: first, electrons incident on the sample occupy a given energy state with a probability given by the Fermi-Dirac distribution function. Secondly, electrons can be transmitted across the sample or reflected in the same reservoir where they came from with a probability given by the quantum mechanical transmission/reflection coefficients. Equilibrium noise refers to the case where no bias voltage is applied between the leads connected to the sample, where thermal agitation alone allows the electrons close to the Fermi level to tunnel through the sample. In general, equilibrium noise is related to the conductance of the sample via the Johnson-Nyquist formula. In the presence of a bias, in the classical regime, one expects to recover the full shot noise < {Delta}{sup 2}I >= 2I{Delta}{mu} as was observed a long time ago in vacuum diodes. In the Mesoscopic regime, however, excess noise is reduced below the shot noise level. The author introduces a more intuitive picture, where the current passing through the device is a superposition of pulses, or electron wave packets, which can be transmitted or reflected.

Single-source mechanical loading system produces biaxial stresses in cylinders

Science.gov (United States)

Flower, J. F.; Stafford, R. L.

1967-01-01

Single-source mechanical loading system proportions axial-to-hoop tension loads applied to cylindrical specimens. The system consists of hydraulic, pneumatic, and lever arrangements which produce biaxial loading ratios.

An Oblivious O(1)-Approximation for Single Source Buy-at-Bulk

KAUST Repository

Goel, Ashish; Post, Ian

2009-01-01

We consider the single-source (or single-sink) buy-at-bulk problem with an unknown concave cost function. We want to route a set of demands along a graph to or from a designated root node, and the cost of routing x units of flow along an edge

Gaze Embeddings for Zero-Shot Image Classification

NARCIS (Netherlands)

Karessli, N.; Akata, Z.; Schiele, B.; Bulling, A.

2017-01-01

Zero-shot image classification using auxiliary information, such as attributes describing discriminative object properties, requires time-consuming annotation by domain experts. We instead propose a method that relies on human gaze as auxiliary information, exploiting that even non-expert users have

76 FR 31964 - Announcement of the Award of Nine Single-Source Expansion Supplement Grants

Science.gov (United States)

2011-06-02

... the Award of Nine Single-Source Expansion Supplement Grants AGENCY: Office of Refugee Resettlement, ACF, HHS. ACTION: Notice to announce the award of nine single-source expansion supplement grants to.... Maintaining Funding Level of Matching Grant Program (a) Maintaining Funding Level--Subject to the availability...

Using deep neural networks to augment NIF post-shot analysis

Science.gov (United States)

Humbird, Kelli; Peterson, Luc; McClarren, Ryan; Field, John; Gaffney, Jim; Kruse, Michael; Nora, Ryan; Spears, Brian

2017-10-01

Post-shot analysis of National Ignition Facility (NIF) experiments is the process of determining which simulation inputs yield results consistent with experimental observations. This analysis is typically accomplished by running suites of manually adjusted simulations, or Monte Carlo sampling surrogate models that approximate the response surfaces of the physics code. These approaches are expensive and often find simulations that match only a small subset of observables simultaneously. We demonstrate an alternative method for performing post-shot analysis using inverse models, which map directly from experimental observables to simulation inputs with quantified uncertainties. The models are created using a novel machine learning algorithm which automates the construction and initialization of deep neural networks to optimize predictive accuracy. We show how these neural networks, trained on large databases of post-shot simulations, can rigorously quantify the agreement between simulation and experiment. This work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

MICROORGANISMS: A MARVELOUS SOURCE OF SINGLE CELL PROTEINS

Directory of Open Access Journals (Sweden)

Agam Nangul

2013-08-01

Full Text Available The increasing global population living below the poverty line is driving the scientific community to search for non-conventional protein sources that can replace conventional expensive ones. Microbial proteins, or single-cell protein (SCP, represent a potential future nutrient source for human food and animal feed. These microbial proteins can be grown rapidly on substrates with minimum dependence on soil, water and climate conditions. They can be produced from algae, fungi and bacteria the chief sources of SCP. It is convenient to use microorganisms for production of SCP as they grow rapidly and have high protein content. Industrially, they can be produced from algal biomass, yeast, fungi. There are several other ways of getting SCP as well. Despite numerous advantages of SCP, they have disadvantages and toxic effects too, especially related to mycotoxins and bacterial toxins.

Duopoly Market Analysis within One-Shot Decision Framework with Asymmetric Possibilistic Information

Directory of Open Access Journals (Sweden)

Peijun Guo

2010-12-01

Full Text Available In this paper, a newly emerging duopoly market with a short life cycle is analyzed. The partially known information of market is characterized by the possibility distribution of the parameter in the demand function. Since the life cycle of the new product is short, how many products should be produced by two rival firms is a typical one-shot decision problem. Within the one-shot decision framework, the possibilistic Cournot equilibrium is obtained for the optimal production level of each firm in a duopoly market with asymmetrical possibilistic information. The analysis results show that the proposed approaches are reasonable for one-shot decision problems, which are extensively encountered in business and economics.

Time-domain single-source integral equations for analyzing scattering from homogeneous penetrable objects

KAUST Repository

Valdés, Felipe

2013-03-01

Single-source time-domain electric-and magnetic-field integral equations for analyzing scattering from homogeneous penetrable objects are presented. Their temporal discretization is effected by using shifted piecewise polynomial temporal basis functions and a collocation testing procedure, thus allowing for a marching-on-in-time (MOT) solution scheme. Unlike dual-source formulations, single-source equations involve space-time domain operator products, for which spatial discretization techniques developed for standalone operators do not apply. Here, the spatial discretization of the single-source time-domain integral equations is achieved by using the high-order divergence-conforming basis functions developed by Graglia alongside the high-order divergence-and quasi curl-conforming (DQCC) basis functions of Valdés The combination of these two sets allows for a well-conditioned mapping from div-to curl-conforming function spaces that fully respects the space-mapping properties of the space-time operators involved. Numerical results corroborate the fact that the proposed procedure guarantees accuracy and stability of the MOT scheme. © 2012 IEEE.

Different intensities of basketball drills affect jump shot accuracy of expert and junior players

Directory of Open Access Journals (Sweden)

Giuseppe Marcolin

2018-02-01

Full Text Available Background In basketball a maximum accuracy at every game intensity is required while shooting. The aim of the present study was to investigate the acute effect of three different drill intensity simulation protocols on jump shot accuracy in expert and junior basketball players. Materials & Methods Eleven expert players (age 26 ± 6 yrs, weight 86 ± 11 kg, height 192 ± 8 cm and ten junior players (age 18 ± 1 yrs, weight 75 ± 12 kg, height 184 ± 9 cm completed three series of twenty jump shots at three different levels of exertion. Counter Movement Jump (CMJ height was also measured after each series of jump shots. Exertion’s intensity was induced manipulating the basketball drills. Heart rate was measured for the whole duration of the tests while the rating of perceived exertion (RPE was collected at the end of each series of shots. Results Heart rate and rating of perceived exertion (RPE were statistically different in the three conditions for both expert and junior players. CMJ height remained almost unchanged in both groups. Jump shot accuracy decreased with increasing drills intensity both in experts and junior players. Expert players showed higher accuracy than junior players for all the three levels of exertion (83% vs 64%, p < 0.001; 75% vs 57%, p < 0.05; 76% vs 60%, p < 0.01. Moreover, for the most demanding level of exertion, experts showed a higher accuracy in the last ten shots compared to the first ten shots (82% vs 70%, p < 0.05. Discussion Experts coped better with the different exertion’s intensities, thus maintaining a higher level of performance. The introduction of technical short bouts of high-intensity sport-specific exercises into skill sessions should be proposed to improve jump shot accuracy during matches.

First-time viewers' comprehension of films: bridging shot transitions.

Science.gov (United States)

Ildirar, Sermin; Schwan, Stephan

2015-02-01

Which perceptual and cognitive prerequisites must be met in order to be able to comprehend a film is still unresolved and a controversial issue. In order to gain some insights into this issue, our field experiment investigates how first-time adult viewers extract and integrate meaningful information across film cuts. Three major types of commonalities between adjacent shots were differentiated, which may help first-time viewers with bridging the shots: pictorial, causal, and conceptual. Twenty first-time, 20 low-experienced and 20 high-experienced viewers from Turkey were shown a set of short film clips containing these three kinds of commonalities. Film clips conformed also to the principles of continuity editing. Analyses of viewers' spontaneous interpretations show that first-time viewers indeed are able to notice basic pictorial (object identity), causal (chains of activity), as well as conceptual (links between gaze direction and object attention) commonalities between shots due to their close relationship with everyday perception and cognition. However, first-time viewers' comprehension of the commonalities is to a large degree fragile, indicating the lack of a basic notion of what constitutes a film. © 2014 The British Psychological Society.

Shot-Peening Effect on High Cycling Fatigue of Al-Cu Alloy

Science.gov (United States)

Fouad, Yasser; Metwally, Mostafa El

2013-12-01

The present work was aimed at evaluating the effects of shot-peening on the high cycle fatigue performance of the age-hardening aircraft alloy Al 2024 at different almen intensities. Shot-peening to full coverage (100 pct) was performed using spherically conditioned cut wire (SCCW 14) with an average shot size of 0.36 mm and at almen intensities of 0.1, 0.2, and 0.3 mmA. After applying the various mechanical surface treatments, the changes in the surface and near-surface layer properties such as microhardness, residual stress-depth profiles, and surface roughness were determined. The microhardness, surface roughness, and the residual stresses increased proportionally with the almen intensity. Electropolitically polished conditions were used as reference in the mechanically surface treated specimens. A significant improvement was seen in the fatigue performance of the 0.1 mmA.

Bunch by bunch beam monitoring in 3rd and 4th generation light sources by means of single crystal diamond detectors and quantum well devices

Science.gov (United States)

Antonelli, M.; Di Fraia, M.; Tallaire, A.; Achard, J.; Carrato, S.; Menk, R. H.; Cautero, G.; Giuressi, D.; Jark, W. H.; Biasiol, G.; Ganbold, T.; Oliver, K.; Callegari, C.; Coreno, M.; De Sio, A.; Pace, E.

2012-10-01

New generation Synchrotron Radiation (SR) sources and Free Electron Lasers (FEL) require novel concepts of beam diagnostics to keep photon beams under surveillance, asking for simultaneous position and intensity monitoring. To deal with high power load and short time pulses provided by these sources, novel materials and methods are needed for the next generation BPMs. Diamond is a promising material for the production of semitransparent in situ X-ray BPMs withstanding the high dose rates of SR rings and high energy FELs. We report on the development of freestanding, single crystal CVD diamond detectors. Performances in both low and radio frequency SR beam monitoring are presented. For the former, sensitivity deviation was found to be approximately 2%; a 0.05% relative precision in the intensity measurements and a 0.1-μm precision in the position encoding have been estimated. For the latter, single-shot characterizations revealed sub-nanosecond rise-times and spatial precisions below 6 μm, which allowed bunch-by-bunch monitoring in multi-bunch operation. Preliminary measurements at the Fermi FEL have been performed with this detector, extracting quantitative intensity and position information for FEL pulses (~ 100 fs, energy 12 ÷ 60 eV), with a long-term spatial precision of about 85 μm results on FEL radiation damages are also reported. Due to their direct, low-energy band gap, InGaAs quantum well devices too may be used as fast detectors for photons ranging from visible to X-ray. Results are reported which show the capability of a novel InGaAs/InAlAs device to detect intensity and position of 100-fs-wide laser pulses.

Processing of transmission data from an uncollimated single photon source

International Nuclear Information System (INIS)

Dikaios, N.; Dinelle, K.; Spinks, T.; Nikita, K.; Thielemans, K.

2006-01-01

The EXACT 3D PET scanner uses a Cs-137 single photon rotating point source for the transmission scan. As the source is un-collimated, the transmission data are contaminated by scatter. It has been suggested that segmentation of the reconstructed image can restore the quantitative information in the image. We study here if the results can be further improved by the application of a scale factor for every transaxial plane

Effect of Shot Peening on Tribological Behaviors of Molybdenum-Thermal Spray Coating using HVOF Method

Directory of Open Access Journals (Sweden)

H. Mohassel

2017-03-01

Full Text Available We have investigated the influence of post-shot peening on Mo-coating as compared to substrate steel 16MnCr5 (according to ZFN-413 A. Shot peening of carburized steel discs with and without Mo-coating was performed by using Shot size S230, Almen intensity 0.42 mm ’A’ and exposure time 96 sec. Tribological properties were analyzed, using pin-on-disc tribometer apparatus, under dry sliding conditions at different specific applied loads, sliding velocities and distance. Typical standardized methods were used for studying of surface integrity parameters (micro-hardness, topography and surface roughness. Surface morphology of the Mo-coating specimens with and without Shot Peening before and after wear was evaluated by Scanning Electron Microscopy. The results showed that shot peening after Mo-coating has considerable effect on improving wear resistance and because of having low friction coefficient has showed better wear behavior and tribologi cal properties over that of the un-peened Mo-coating.

Preparation of Ultracold Atom Clouds at the Shot Noise Level

DEFF Research Database (Denmark)

Gajdacz, M.; Hilliard, A. J.; Kristensen, Mick

2016-01-01

We prepare number stabilized ultracold atom clouds through the real-time analysis of nondestructive images and the application of feedback. In our experiments, the atom number N∼10^6 is determined by high precision Faraday imaging with uncertainty ΔN below the shot noise level, i.e., ΔN... on this measurement, feedback is applied to reduce the atom number to a user-defined target, whereupon a second imaging series probes the number stabilized cloud. By this method, we show that the atom number in ultracold clouds can be prepared below the shot noise level....

High energy x-ray synchrotron radiation analysis of residual stress distribution of shot-peened steels

International Nuclear Information System (INIS)

Tanaka, Keisuke; Akiniwa, Yoshiaki; Kimachi, Hirohisa; Suzuki, Kenji; Yanase, Etsuya; Nishio, Kouji; Kusumi, Yukihiro

2001-01-01

A high energy X-ray beam from synchrotron radiation source SPring-8 was used to determine the residual stress distribution beneath the shot-peened surface of carbon steel plates. By using the monochromatic X-ray beam with an energy of 72 keV, the relation between 2θ and sin 2 ψ was obtained by the side-inclination method upto sin 2 ψ = 0.9. The distribution of the residual stress was determined from the non-linearity of the relation between 2θ and sin 2 ψ. (author)

High-efficiency single-photon source: The photonic wire geometry

DEFF Research Database (Denmark)

Claudon, J.; Bazin, Maela; Malik, Nitin S.

2009-01-01

We present a single-photon-source design based on the emission of a quantum dot embedded in a semiconductor (GaAs) nanowire. The nanowire ends are engineered (efficient metallic mirror and tip taper) to reach a predicted record-high collection efficiency of 90% with a realistic design. Preliminar...

Sourcing for Quality: Cooperating with a Single Supplier or Developing Two Competing Suppliers?

Directory of Open Access Journals (Sweden)

Jingxian Chen

2016-01-01

Full Text Available Supplier efforts regarding product quality are an important issue in outsourcing and play a critical role in a manufacturer’s choice of sourcing strategy. Consider a manufacturer that wants to outsource the manufacturing of two substitute products to external suppliers. This paper studies the strategic interactions under two sourcing strategies: single and dual sourcing. A four-stage noncooperative game model is established to describe each member’s decisions. We further propose four decision scenarios: single sourcing with and without manufacturer quality investment sharing and dual sourcing when suppliers cooperate or do not cooperate on quality decisions. By the backward induction approach, we obtain analytical equilibrium solutions for each decision scenario. By comparing each pair of equilibrium profiles, we find that an appropriate proportion of quality investment sharing by the manufacturer can enable a cooperating strategy with a single supplier to be the dominant strategy. When the manufacturer does not want to share or does not want to share a relatively large portion of its supplier’s quality investment, it will always prefer to develop two competing suppliers when the cost of dual sourcing is sufficiently low. However, dual sourcing can be extremely risky for the manufacturer because the suppliers could provide a relatively low product quality level by cooperating on the quality decision to extract the manufacturer’s profit.

Polio and the Vaccine (Shot) to Prevent It

Science.gov (United States)

... and Teen Vaccine Resources Related Links Vaccines & Immunizations Polio and the Vaccine (Shot) to Prevent It Language: ... recommend all children get the vaccine. What is polio? Polio (or poliomyelitis) is a disease caused by ...

Clarifying beliefs underlying hunter intentions to support a ban on lead shot

Science.gov (United States)

Schroeder, Susan A.; Fulton, David C.; Doncarlos, Kathy

2016-01-01

Shot from hunting adds toxic lead to environments worldwide. Existing lead shot regulations have been instituted with little understanding of hunter beliefs and attitudes. This study applied the Theory of Reasoned Action, using a multilevel, multivariate approach, to clarify how positive and negative beliefs relate to attitudes about a ban on lead shot. Structure coefficients and commonality analysis were employed to further examine relationships between beliefs and attitudes. Results suggest that while both positive and negative outcomes influence attitudes, positive outcomes were more influential for supporters and negative beliefs for opposers. Management may need to focus on the results from hunters who indicated that they would be unlikely to support a ban, as these hunters include those who may actively oppose additional efforts to regulate lead.

Near shot-noise limited time-resolved circular dichroism pump-probe spectrometer

Science.gov (United States)

Stadnytskyi, Valentyn; Orf, Gregory S.; Blankenship, Robert E.; Savikhin, Sergei

2018-03-01

We describe an optical near shot-noise limited time-resolved circular dichroism (TRCD) pump-probe spectrometer capable of reliably measuring circular dichroism signals in the order of μdeg with nanosecond time resolution. Such sensitivity is achieved through a modification of existing TRCD designs and introduction of a new data processing protocol that eliminates approximations that have caused substantial nonlinearities in past measurements and allows the measurement of absorption and circular dichroism transients simultaneously with a single pump pulse. The exceptional signal-to-noise ratio of the described setup makes the TRCD technique applicable to a large range of non-biological and biological systems. The spectrometer was used to record, for the first time, weak TRCD kinetics associated with the triplet state energy transfer in the photosynthetic Fenna-Matthews-Olson antenna pigment-protein complex.

Space based lidar shot pattern targeting strategies for small targets such as streams

Science.gov (United States)

Spiers, Gary D.

2001-01-01

An analysis of the effectiveness of four different types of lidar shot distribution is conducted to determine which is best for concentrating shots in a given location. A simple preemptive targeting strategy is found to work as adequately as a more involved dynamic strategy for most target sizes considered.

Gun Shot Wound to the Chest of a Military Working Dog

Science.gov (United States)

2009-06-01

special care ought to be taken when either human or dog is on isolation precautions. Also, animals without airway compromise should be muzzled , as...Gun Shot Wound to Chest of Military Working Dog Military Medicine Radiology Corner, Volume 174, June, 2009 Radiology Corner Gun Shot Wound to...the Chest of a Military Working Dog Guarantor: 2LT Meghan Galer, MSC, USA1 Contributors: 2LT Meghan Galer, MSC, USA1; Donna Magid, MD, MEd2; Les

Surface characterization of III-V MOCVD films from heterocyclic single-source precursors; Oberflaechencharakterisierung von III-V MOCVD-Filmen aus heterozyklischen Single Source Precursoren

Energy Technology Data Exchange (ETDEWEB)

Seemayer, Andreas

2009-07-13

In the present thesis the sublimation and evaporation properties of heterocyclic gallium and antimony containing single-source precursors as well as the chemical composition and morphology of the films fabricated from this were studied. The single-source precursors available by a new synthesis route were characterized concerning their evaporation properties and the obtained films studied surface-physically. By this way the process parameters were optimized and the applicability of the single-source precursors in HV-MOCVD processes studied. By evaporation experiments in the UHV it could be shown that thereby lighter ligands like ethyl- and methyl-groups lead to a lower contamination of the reaction space with carbon containing molecules. Furthermore it was expected that the 6-rings synthetized with short ligands exhibit a high stability. This however could not be confirmed. By unwanted parasitary reactions in the gaseous phase respectively dissociative sublimation in the gaseous phase a deposition of GaSb with these precursors was not possible. The 4-ring stabilized with tertiary-butyl and ethyl-groups caused in the evaporation the largest contamination of the gaseous phase, becauselonger-chain hydrocarbons exhibil only a bad pump cross section. By parasitary reactions originating elementary antimony is detectable in the gaseous phase. The films were studied concerning their chemical composition and their transport- respectively storage-conditioned surface contamination. Furthermore it has become clear that not only a purely synthetized precursor substance but also the reactor design is deciding for a successful deposition and a high film quality. First by successive optimization of the evaporation geometry it was possible to reduce the roughness of the produced GaSb films down to about 10 nm-30 nm.

Methods of forming single source precursors, methods of forming polymeric single source precursors, and single source precursors formed by such methods

Science.gov (United States)

Fox, Robert V.; Rodriguez, Rene G.; Pak, Joshua J.; Sun, Chivin; Margulieux, Kelsey R.; Holland, Andrew W.

2014-09-09

Methods of forming single source precursors (SSPs) include forming intermediate products having the empirical formula 1/2{L.sub.2N(.mu.-X).sub.2M'X.sub.2}.sub.2, and reacting MER with the intermediate products to form SSPs of the formula L.sub.2N(.mu.-ER).sub.2M'(ER).sub.2, wherein L is a Lewis base, M is a Group IA atom, N is a Group IB atom, M' is a Group IIIB atom, each E is a Group VIB atom, each X is a Group VIIA atom or a nitrate group, and each R group is an alkyl, aryl, vinyl, (per)fluoro alkyl, (per)fluoro aryl, silane, or carbamato group. Methods of forming polymeric or copolymeric SSPs include reacting at least one of HE.sup.1R.sup.1E.sup.1H and MER with one or more substances having the empirical formula L.sub.2N(.mu.-ER).sub.2M'(ER).sub.2 or L.sub.2N(.mu.-X).sub.2M'(X).sub.2 to form a polymeric or copolymeric SSP. New SSPs and intermediate products are formed by such methods.

Is Attribute-Based Zero-Shot Learning an Ill-Posed Strategy?

KAUST Repository

Alabdulmohsin, Ibrahim; Cisse, Moustapha; Zhang, Xiangliang

2016-01-01

One transfer learning approach that has gained a wide popularity lately is attribute-based zero-shot learning. Its goal is to learn novel classes that were never seen during the training stage. The classical route towards realizing this goal is to incorporate a prior knowledge, in the form of a semantic embedding of classes, and to learn to predict classes indirectly via their semantic attributes. Despite the amount of research devoted to this subject lately, no known algorithm has yet reported a predictive accuracy that could exceed the accuracy of supervised learning with very few training examples. For instance, the direct attribute prediction (DAP) algorithm, which forms a standard baseline for the task, is known to be as accurate as supervised learning when as few as two examples from each hidden class are used for training on some popular benchmark datasets! In this paper, we argue that this lack of significant results in the literature is not a coincidence; attribute-based zero-shot learning is fundamentally an ill-posed strategy. The key insight is the observation that the mechanical task of predicting an attribute is, in fact, quite different from the epistemological task of learning the “correct meaning” of the attribute itself. This renders attribute-based zero-shot learning fundamentally ill-posed. In more precise mathematical terms, attribute-based zero-shot learning is equivalent to the mirage goal of learning with respect to one distribution of instances, with the hope of being able to predict with respect to any arbitrary distribution. We demonstrate this overlooked fact on some synthetic and real datasets. The data and software related to this paper are available at https://mine. kaust.edu.sa/Pages/zero-shot-learning.aspx. © Springer International Publishing AG 2016.

Is Attribute-Based Zero-Shot Learning an Ill-Posed Strategy?

KAUST Repository

Alabdulmohsin, Ibrahim

2016-09-03

One transfer learning approach that has gained a wide popularity lately is attribute-based zero-shot learning. Its goal is to learn novel classes that were never seen during the training stage. The classical route towards realizing this goal is to incorporate a prior knowledge, in the form of a semantic embedding of classes, and to learn to predict classes indirectly via their semantic attributes. Despite the amount of research devoted to this subject lately, no known algorithm has yet reported a predictive accuracy that could exceed the accuracy of supervised learning with very few training examples. For instance, the direct attribute prediction (DAP) algorithm, which forms a standard baseline for the task, is known to be as accurate as supervised learning when as few as two examples from each hidden class are used for training on some popular benchmark datasets! In this paper, we argue that this lack of significant results in the literature is not a coincidence; attribute-based zero-shot learning is fundamentally an ill-posed strategy. The key insight is the observation that the mechanical task of predicting an attribute is, in fact, quite different from the epistemological task of learning the “correct meaning” of the attribute itself. This renders attribute-based zero-shot learning fundamentally ill-posed. In more precise mathematical terms, attribute-based zero-shot learning is equivalent to the mirage goal of learning with respect to one distribution of instances, with the hope of being able to predict with respect to any arbitrary distribution. We demonstrate this overlooked fact on some synthetic and real datasets. The data and software related to this paper are available at https://mine. kaust.edu.sa/Pages/zero-shot-learning.aspx. © Springer International Publishing AG 2016.

Laser-driven soft-X-ray undulator source

International Nuclear Information System (INIS)

Fuchs, Matthias

2010-01-01

The experimental results described in this thesis demonstrate the successful synergy between the research fields described above: the development of an undulator source driven by laser-plasma accelerated electron beams. First efforts in this new field have led to the production of radiation in the visible to infrared part of the electromagnetic spectrum [Schlenvoigt et al., 2008]. In contrast to these early achievements, the experiment described here shows the successful production of laser-driven undulator radiation in the soft-X-ray range with a remarkable reproducibility. The source produced tunable, collimated beams with a wavelength of ∝17 nm from a compact setup. Undulator spectra were detected in ∝70% of consecutive driver-laser shots, which is a remarkable reproducibility for a first proof-of-concept demonstration using ultra-high intensity laser systems. This can be attributed to a stable electron acceleration scheme as well as to the first application of miniature magnetic quadrupole lenses with laseraccelerated beams. The lenses significantly reduce the electron beam divergence and its angular shot-to-shot fluctuations The setup of this experiment is the foundation of potential university-laboratory-sized, highly-brilliant hard X-ray sources. By increasing the electron energy to about 1 GeV, X-ray pulses with an expected duration of ∝10 fs and a photon energy of 1 keV could be produced in an almost identical arrangement. It can also be used as a testbed for the development of a free-electron laser of significantly smaller dimension than facilities based on conventional accelerators [Gruener et al., 2007]. Such compact sources have the potential for application in many fields of science. In addition, these developments could lead to ideal sources for ultrafast pump-probe experiments due to the perfect synchronization of the X-ray beam to the driver laser. (orig.)

Laser-driven soft-X-ray undulator source

Energy Technology Data Exchange (ETDEWEB)

Fuchs, Matthias

2010-08-04

The experimental results described in this thesis demonstrate the successful synergy between the research fields described above: the development of an undulator source driven by laser-plasma accelerated electron beams. First efforts in this new field have led to the production of radiation in the visible to infrared part of the electromagnetic spectrum [Schlenvoigt et al., 2008]. In contrast to these early achievements, the experiment described here shows the successful production of laser-driven undulator radiation in the soft-X-ray range with a remarkable reproducibility. The source produced tunable, collimated beams with a wavelength of {proportional_to}17 nm from a compact setup. Undulator spectra were detected in {proportional_to}70% of consecutive driver-laser shots, which is a remarkable reproducibility for a first proof-of-concept demonstration using ultra-high intensity laser systems. This can be attributed to a stable electron acceleration scheme as well as to the first application of miniature magnetic quadrupole lenses with laseraccelerated beams. The lenses significantly reduce the electron beam divergence and its angular shot-to-shot fluctuations The setup of this experiment is the foundation of potential university-laboratory-sized, highly-brilliant hard X-ray sources. By increasing the electron energy to about 1 GeV, X-ray pulses with an expected duration of {proportional_to}10 fs and a photon energy of 1 keV could be produced in an almost identical arrangement. It can also be used as a testbed for the development of a free-electron laser of significantly smaller dimension than facilities based on conventional accelerators [Gruener et al., 2007]. Such compact sources have the potential for application in many fields of science. In addition, these developments could lead to ideal sources for ultrafast pump-probe experiments due to the perfect synchronization of the X-ray beam to the driver laser. (orig.)

One-shot valve may be remotely actuated

Science.gov (United States)

Kami, S.

1965-01-01

One-shot valve, with spring-loaded plunger and sealing diaphragm, incorporates an emergency release actuated by a remote sensor. The plunger is released by the electrical melting of a fuse link and pierces the valve seal. The valve lowers fluid pressure in a container without losing the contained fluid.

Automatic video shot boundary detection using k-means clustering and improved adaptive dual threshold comparison

Science.gov (United States)

Sa, Qila; Wang, Zhihui

2018-03-01

At present, content-based video retrieval (CBVR) is the most mainstream video retrieval method, using the video features of its own to perform automatic identification and retrieval. This method involves a key technology, i.e. shot segmentation. In this paper, the method of automatic video shot boundary detection with K-means clustering and improved adaptive dual threshold comparison is proposed. First, extract the visual features of every frame and divide them into two categories using K-means clustering algorithm, namely, one with significant change and one with no significant change. Then, as to the classification results, utilize the improved adaptive dual threshold comparison method to determine the abrupt as well as gradual shot boundaries.Finally, achieve automatic video shot boundary detection system.

A Study on the Microstructural Evolution of a Low Alloy Steel by Different Shot Peening Treatments

Directory of Open Access Journals (Sweden)

Juan González

2018-03-01

Full Text Available Recent studies have shown that severe shot peening can be categorized as a severe plastic deformation surface treatment that is able to strongly modify the microstructure of the surface layer of materials, by both increasing the dislocation density and introducing a large number of defects that define new grain boundaries and form ultrafine structure. In this work, conventional shot peening and severe shot peening treatments were applied to 39NiCrMo3 steel samples. The samples were characterized in terms of microstructure, surface roughness, microhardness, residual stresses, and surface work-hardening as a function of surface coverage. Particular attention was focused on the analysis of the microstructure to assess the evolution of grain size from the surface to the inner material to capture the gradient microstructure. Severe shot peening proved to cause a more remarkable improvement of the general mechanical characteristics compared to conventional shot peening; more significant improvement was associated with the microstructural alteration induced by the treatment. Our datas provide a detailed verification of the relationship between shot peening treatment parameters and the microstructure evolution from the treated surface to the core material.

Sounding out the logo shot

OpenAIRE

Nicolai Jørgensgaard Graakjær

2013-01-01

This article focuses on how sound in combination with visuals (i.e. ‘branding by’) may possibly affect the signifying potentials (i.e. ‘branding effect’) of products and corporate brands (i.e. ‘branding of’) during logo shots in television commercials (i.e. ‘branding through’). This particular focus adds both to the understanding of sound in television commercials and to the understanding of sound brands. The article firstly presents a typology of sounds. Secondly, this typology is applied...

Post-processing with linear optics for improving the quality of single-photon sources

International Nuclear Information System (INIS)

Berry, Dominic W; Scheel, Stefan; Myers, Casey R; Sanders, Barry C; Knight, Peter L; Laflamme, Raymond

2004-01-01

Triggered single-photon sources produce the vacuum state with non-negligible probability, but produce a much smaller multiphoton component. It is therefore reasonable to approximate the output of these photon sources as a mixture of the vacuum and single-photon states. We show that it is impossible to increase the probability for a single photon using linear optics and photodetection on fewer than four modes. This impossibility is due to the incoherence of the inputs; if the inputs were pure-state superpositions, it would be possible to obtain a perfect single-photon output. In the more general case, a chain of beam splitters can be used to increase the probability for a single photon, but at the expense of adding an additional multiphoton component. This improvement is robust against detector inefficiencies, but is degraded by distinguishable photons, dark counts or multiphoton components in the input

Bright quantum dot single photon source based on a low Q defect cavity

DEFF Research Database (Denmark)

Maier, Sebastian; Gold, Peter; Forchel, A.

2014-01-01

The quasi-planar single photon source presented in this paper shows an extraction efficiency of 42% without complex photonic resonator geometries or lithography steps as well as a high purity with a g2(0) value of 0.023.......The quasi-planar single photon source presented in this paper shows an extraction efficiency of 42% without complex photonic resonator geometries or lithography steps as well as a high purity with a g2(0) value of 0.023....

A practical globalization of one-shot optimization for optimal design of tokamak divertors

Energy Technology Data Exchange (ETDEWEB)

Blommaert, Maarten, E-mail: maarten.blommaert@kuleuven.be [Institute of Energy and Climate Research (IEK-4), FZ Jülich GmbH, D-52425 Jülich (Germany); Dekeyser, Wouter; Baelmans, Martine [KU Leuven, Department of Mechanical Engineering, 3001 Leuven (Belgium); Gauger, Nicolas R. [TU Kaiserslautern, Chair for Scientific Computing, 67663 Kaiserslautern (Germany); Reiter, Detlev [Institute of Energy and Climate Research (IEK-4), FZ Jülich GmbH, D-52425 Jülich (Germany)

2017-01-01

In past studies, nested optimization methods were successfully applied to design of the magnetic divertor configuration in nuclear fusion reactors. In this paper, so-called one-shot optimization methods are pursued. Due to convergence issues, a globalization strategy for the one-shot solver is sought. Whereas Griewank introduced a globalization strategy using a doubly augmented Lagrangian function that includes primal and adjoint residuals, its practical usability is limited by the necessity of second order derivatives and expensive line search iterations. In this paper, a practical alternative is offered that avoids these drawbacks by using a regular augmented Lagrangian merit function that penalizes only state residuals. Additionally, robust rank-two Hessian estimation is achieved by adaptation of Powell's damped BFGS update rule. The application of the novel one-shot approach to magnetic divertor design is considered in detail. For this purpose, the approach is adapted to be complementary with practical in parts adjoint sensitivities. Using the globalization strategy, stable convergence of the one-shot approach is achieved.

Effects of the near field on source-independent q estimation

NARCIS (Netherlands)

Shigapov, R.; Kashtan, B.; Droujinine, A.; Mulder, W.A.

2013-01-01

We consider the problem of Q estimation from microseismic and from perforation shot data. Assuming that the source wavelet is not well known, we focused on the spectral ratio method and on source-independent viscoelastic full waveform inversion. We derived 3-D near-field approximations of monopole

Temporal resolution and motion artifacts in single-source and dual-source cardiac CT.

Science.gov (United States)

Schöndube, Harald; Allmendinger, Thomas; Stierstorfer, Karl; Bruder, Herbert; Flohr, Thomas

2013-03-01

The temporal resolution of a given image in cardiac computed tomography (CT) has so far mostly been determined from the amount of CT data employed for the reconstruction of that image. The purpose of this paper is to examine the applicability of such measures to the newly introduced modality of dual-source CT as well as to methods aiming to provide improved temporal resolution by means of an advanced image reconstruction algorithm. To provide a solid base for the examinations described in this paper, an extensive review of temporal resolution in conventional single-source CT is given first. Two different measures for assessing temporal resolution with respect to the amount of data involved are introduced, namely, either taking the full width at half maximum of the respective data weighting function (FWHM-TR) or the total width of the weighting function (total TR) as a base of the assessment. Image reconstruction using both a direct fan-beam filtered backprojection with Parker weighting as well as using a parallel-beam rebinning step are considered. The theory of assessing temporal resolution by means of the data involved is then extended to dual-source CT. Finally, three different advanced iterative reconstruction methods that all use the same input data are compared with respect to the resulting motion artifact level. For brevity and simplicity, the examinations are limited to two-dimensional data acquisition and reconstruction. However, all results and conclusions presented in this paper are also directly applicable to both circular and helical cone-beam CT. While the concept of total TR can directly be applied to dual-source CT, the definition of the FWHM of a weighting function needs to be slightly extended to be applicable to this modality. The three different advanced iterative reconstruction methods examined in this paper result in significantly different images with respect to their motion artifact level, despite exactly the same amount of data being used

Temporal resolution and motion artifacts in single-source and dual-source cardiac CT

International Nuclear Information System (INIS)

Schöndube, Harald; Allmendinger, Thomas; Stierstorfer, Karl; Bruder, Herbert; Flohr, Thomas

2013-01-01

Purpose: The temporal resolution of a given image in cardiac computed tomography (CT) has so far mostly been determined from the amount of CT data employed for the reconstruction of that image. The purpose of this paper is to examine the applicability of such measures to the newly introduced modality of dual-source CT as well as to methods aiming to provide improved temporal resolution by means of an advanced image reconstruction algorithm. Methods: To provide a solid base for the examinations described in this paper, an extensive review of temporal resolution in conventional single-source CT is given first. Two different measures for assessing temporal resolution with respect to the amount of data involved are introduced, namely, either taking the full width at half maximum of the respective data weighting function (FWHM-TR) or the total width of the weighting function (total TR) as a base of the assessment. Image reconstruction using both a direct fan-beam filtered backprojection with Parker weighting as well as using a parallel-beam rebinning step are considered. The theory of assessing temporal resolution by means of the data involved is then extended to dual-source CT. Finally, three different advanced iterative reconstruction methods that all use the same input data are compared with respect to the resulting motion artifact level. For brevity and simplicity, the examinations are limited to two-dimensional data acquisition and reconstruction. However, all results and conclusions presented in this paper are also directly applicable to both circular and helical cone-beam CT. Results: While the concept of total TR can directly be applied to dual-source CT, the definition of the FWHM of a weighting function needs to be slightly extended to be applicable to this modality. The three different advanced iterative reconstruction methods examined in this paper result in significantly different images with respect to their motion artifact level, despite exactly the same

ECG-gated quiescent-interval single-shot MR angiography of the lower extremities: Initial experience at 3 T

International Nuclear Information System (INIS)

Knobloch, G.; Gielen, M.; Lauff, M.-T.; Romano, V.C.; Schmitt, P.; Rick, M.; Kröncke, T.J.; Huppertz, A.; Hamm, B.; Wagner, M.

2014-01-01

Aim: To evaluate the feasibility of unenhanced electrocardiography (ECG)-gated quiescent-interval single-shot magnetic resonance angiography (QISS-MRA) of the lower extremities at 3 T. Materials and methods: Twenty-five patients with known or suspected peripheral arterial disease underwent ECG-gated QISS-MRA and contrast-enhanced MRA (CE-MRA) at 3 T. Two independent readers performed a per-segment evaluation of the MRA datasets. Image quality was rated on a four-point scale (1 = excellent to 4 = non-diagnostic; presented as medians with interquartile range). Diagnostic performance of QISS-MRA was evaluated using CE-MRA as the reference standard. Results: QISS-MRA and CE-MRA of all patients were considered for analysis, resulting in 807 evaluated vessel segments for each MRA technique. Readers 1 and 2 rated image quality of QISS-MRA as diagnostic in 97.3% and 97% of the vessel segments, respectively. CE-MRA was rated diagnostic in all vessel segments. Image quality of the proximal vessel segments, including the infrarenal aorta, iliac arteries, and common femoral artery, was significantly lower on QISS-MRA compared to CE-MRA [image quality score across readers: 2 (1,3) versus 1 (1,1) p < 0.001]. In the more distal vessel segments, image quality of QISS-MRA was excellent and showed no significant difference compared to CE-MRA [image quality score across readers: 1 (1,1) versus 1 (1,1) p = 0.036]. Diagnostic performance of QISS-MRA was as follows (across readers): sensitivity: 87.5% (95% CI: 80.2–92.4%); specificity: 96.1% (95% CI: 93.6–97.6%); diagnostic accuracy: 94.9% (95% CI: 92.6–96.5%). Conclusions: QISS-MRA of the lower extremities is feasible at 3 T and provides high image quality, especially in the distal vessel segments

Effect of high energy shot peening pressure on the stress corrosion cracking of the weld joint of 304 austenitic stainless steel

International Nuclear Information System (INIS)

Zhiming, Lu; Laimin, Shi; Shenjin, Zhu; Zhidong, Tang; Yazhou, Jiang

2015-01-01

The weld joint of 304 stainless steel is treated using high energy shot peening(HESP) with various shot peening pressures. The grain size and metallographic microstructure of the specimen surface layer are analyzed using the X-ray diffraction method, and the surface hardness is measured. Slow strain rate tension tests are then performed to investigate the effect of shot peening pressure on the stress corrosion sensitivity. The results show that in the surface layer of the specimen, the grain refinement, hardness and the strain-induced plastic deformation all increase with the increasing shot peening pressure. Martensitic transformation is observed in the surface layer after being treated with HESP. The martensite phase ratio is found to increase with increasing shot peening pressure. The result also shows that the effects of the shot peening treatment on the stress corrosion sensitivity index depend on the shot peening pressure. When the shot peening pressure is less than 0.4 MPa, the grain refinement effect plays the main role, and the stress corrosion sensitivity index decreases with the increasing shot peening pressure. In contrast, when the shot peening pressure is higher than 0.4 MPa, the martensite transformation effect plays the main role, the stress corrosion sensitivity index increases with increasing shot peening pressure

Shot-to-shot reproducibility in the emission of fast highly charged metal ions from a laser ion source

Czech Academy of Sciences Publication Activity Database

Krása, Josef; Velyhan, Andriy; Margarone, Daniele; Krouský, Eduard; Láska, Leoš; Jungwirth, Karel; Rohlena, Karel; Ullschmied, Jiří; Parys, P.; Ryc, L.; Wolowski, J.

2012-01-01

Roč. 83, č. 2 (2012), , "02B302-1"-"02B302-3" ISSN 0034-6748 R&D Projects: GA ČR(CZ) GAP205/11/1165; GA MŠk(CZ) 7E09092; GA MŠk(CZ) LC528 EU Projects: European Commission(XE) 228334 - LASERLAB-EUROPE Institutional research plan: CEZ:AV0Z10100523; CEZ:AV0Z20430508 Keywords : ion sources * palladium * plasma sources * gold * plasma production by laser Subject RIV: BH - Optics, Masers, Lasers Impact factor: 1.602, year: 2012

Finite element analysis for prediction of the residual stresses induced by shot peening II

International Nuclear Information System (INIS)

Kim, Cheol; Seok, Chang Sung; Yang, Won Ho; Ryu, Myung Hai

2002-01-01

Shot peening is a surface impact treatment widely used to improve the performance of metal parts and welded details subjected to fatigue loading, contact fatigue, stress corrosion and other damage mechanisms. The better performance of the peened parts is mainly due to the residual stresses resulting from the plastic deformation of the surface layers of the material caused by the impact of the shot. In this paper the simulation technique is applied to predict the magnitude and distribution of the residual stress and plastic deformation caused by shot peening with the help of finite element analysis

AN ECOLOGICAL RISK ASSESSMENT OF LEAD SHOT EXPOSURE IN NON-WATERFOWL AVIAN SPECIES: UPLAND GAME BIRDS AND RAPTORS

Science.gov (United States)

There is increasing concern that birds in terrestrial ecosystems may be exposed to spent lead shot. Evidence exists that upland birds, particularly mourning doves (Zenaida macroura), ingest spent lead shot and that raptors ingest lead shot by consuming wounded game. Mortality, ne...

Cross correlations of quantum key distribution based on single-photon sources

International Nuclear Information System (INIS)

Dong Shuangli; Wang Xiaobo; Zhang Guofeng; Sun Jianhu; Zhang Fang; Xiao Liantuan; Jia Suotang

2009-01-01

We theoretically analyze the second-order correlation function in a quantum key distribution system with real single-photon sources. Based on single-event photon statistics, the influence of the modification caused by an eavesdropper's intervention and the effects of background signals on the cross correlations between authorized partners are presented. On this basis, we have shown a secure range of correlation against the intercept-resend attacks.

Full report of laser doppler velocimetry (Het-V) data, results , and analysis for pRad shot 0632

Energy Technology Data Exchange (ETDEWEB)

Tupa, Dale [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Tainter, Amy Marie [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2016-06-21

This was a collaborative shot with AWE investigators Paul Willis-Patel, David Bell, Seth Grant, David Tarr, and James Richley. The shot was assembled in Los Alamos, after which David Bell set up the probe holder and finalized the alignment. The probe holder location and configuration was modified from previous years to make room for the laser illuminated visible imaging diagnostic. The LANL pRad PDV team was Dale Tupa, Amy Tainter, and Patrick Medina. This shot had three PDV probes: one aimed at the center, one aimed at a feature, one aimed at the reverse side of the shot. The shot also had 9 points of a spectroscopy diagnostic. The pRad team helped set up and field the spectroscopy, but did not help with any data analysis. (The support documentation for the PDV results includes a timing map for the spectroscopy.) Please direct questions on the velocimetry to Dale Tupa or Amy Tainter. The shot radiographs were classified, but the data from the optical diagnostics are not.

Astronomy in Denver: Probing Interstellar Circular Polarization with Polvis, a Full Stokes Single Shot Polarimeter

Science.gov (United States)

Wolfe, Tristan; Stencel, Robert E.

2018-06-01

Measurements of optical circular polarization (Stokes V) introduced by dust grains in the ISM are important for two main reasons. First of all, the polarization itself contains information about the metallic versus dielectric composition of the dust grains themselves (H. C. van de Hulst 1957, textbook). Additionally, circular polarization can help constrain the interstellar component of the polarization of any source that may have intrinsic polarization, which needs to be calibrated for astrophysical study. Though interstellar circular polarization has been observed (P. G. Martin 1972, MNRAS 159), most broadband measurements of ISM polarization include linear polarization only (Stokes Q and U), due to the relatively low circular polarization signal and the added instrumentation complexity of including V-measurement capability. Prior circular polarization measurements have also received very little follow-up in the past several decades, even as polarimeters have become more accurate due to advances in technology. The University of Denver is pursuing these studies with POLVIS, a prototype polarimeter that utilizes a stress-engineered optic ("SEO", A. K. Spilman and T. G. Brown 2007, Applied Optics IP 46) to produce polarization-dependent PSFs (A. M. Beckley and T. G. Brown 2010, Proc SPIE 7570). These PSFs are analyzed to provide simultaneous Stokes I, Q, U, and V measurements, in a single beam and single image, along the line-of-sight to point source-like objects. Polvis is the first polarimeter to apply these optics and measurement techniques for astronomical observations. We present the first results of this instrument in B, V, and R wavebands, providing a fresh look at full Stokes interstellar polarization. Importantly, this set of efforts will constrain the ISM contribution to the polarization with respect to intrinsic stellar components. The authors are grateful to the estate of William Herschel Womble for the support of astronomy at the University of Denver

Subelectron transport in single-electron-tunneling arrays

Science.gov (United States)

Kaplan, Daniel M.; Sverdlov, Victor A.; Likharev, Konstantin K.

2002-05-01

We have shown that a special distribution of background charges in islands of single-electron-tunneling arrays can completely suppress its Coulomb blockade and at the same time reduce substantially its shot noise at low applied voltages. In particular the Fano factor F can approach the minimum value Fmin=1/Nopalescence.

Geotomography using refraction fan shots

Science.gov (United States)

Pavlis, Gary L.

1986-05-01

This paper introduces a new method for imaging lateral variations in the seismic velocity structure of the earth. The discussion is centered around the geometry of a pilot experiment conducted in Salt Creek valley near Bloomington, Indiana, but the methodology is more general in scope. In the pilot experiment, 24 explosions were fired at equal intervals around a circular area 190 m in diameter and recorded by geophones positioned diametrically opposite the source. Travel time residuals for the fan shots are inverted to estimate lateral velocity variations in a two-dimensional, bowl-shaped image reconstruction region under the circular array. A simple damped least squares inversion worked poorly when delay times were included as additional free parameters in the solution. A parameter separation procedure was more successful. The value of these data in determining structure was analyzed using synthetic data and resolving power calculations. Structure could be determined to high accuracy with little distortion in the center of the circular region where rays crossed from all directions, but results were comparatively poor near the fringes of the region where angular coverage was more limited. Inversion of the Salt Creek data indicates the observed variations in the residuals can be almost completely accounted for by variations in the weathered layer. The refractor velocity is nearly constant to a precision of 0.005 s/km, but there is a suggestion of a slight velocity decrease in the refractor at higher elevations above the water table.

High brightness fiber laser pump sources based on single emitters and multiple single emitters

Science.gov (United States)

Scheller, Torsten; Wagner, Lars; Wolf, Jürgen; Bonati, Guido; Dörfel, Falk; Gabler, Thomas

2008-02-01

Driven by the potential of the fiber laser market, the development of high brightness pump sources has been pushed during the last years. The main approaches to reach the targets of this market had been the direct coupling of single emitters (SE) on the one hand and the beam shaping of bars and stacks on the other hand, which often causes higher cost per watt. Meanwhile the power of single emitters with 100μm emitter size for direct coupling increased dramatically, which also pushed a new generation of wide stripe emitters or multi emitters (ME) of up to 1000μm emitter size respectively "minibars" with apertures of 3 to 5mm. The advantage of this emitter type compared to traditional bars is it's scalability to power levels of 40W to 60W combined with a small aperture which gives advantages when coupling into a fiber. We show concepts using this multiple single emitters for fiber coupled systems of 25W up to 40W out of a 100μm fiber NA 0.22 with a reasonable optical efficiency. Taking into account a further efficiency optimization and an increase in power of these devices in the near future, the EUR/W ratio pushed by the fiber laser manufacturer will further decrease. Results will be shown as well for higher power pump sources. Additional state of the art tapered fiber bundles for photonic crystal fibers are used to combine 7 (19) pump sources to output powers of 100W (370W) out of a 130μm (250μm) fiber NA 0.6 with nominal 20W per port. Improving those TFB's in the near future and utilizing 40W per pump leg, an output power of even 750W out of 250μm fiber NA 0.6 will be possible. Combined Counter- and Co-Propagated pumping of the fiber will then lead to the first 1kW fiber laser oscillator.

Readout-Segmented Echo-Planar Imaging in Diffusion-Weighted MR Imaging in Breast Cancer: Comparison with Single-Shot Echo-Planar Imaging in Image Quality

International Nuclear Information System (INIS)

Kim, Yun Ju; Kim, Sung Hun; Kang, Bong Joo; Park, Chang Suk; Kim, Hyeon Sook; Son, Yo Han; Porter, David Andrew; Song, Byung Joo

2014-01-01

The purpose of this study was to compare the image quality of standard single-shot echo-planar imaging (ss-EPI) and that of readout-segmented EPI (rs-EPI) in patients with breast cancer. Seventy-one patients with 74 breast cancers underwent both ss-EPI and rs-EPI. For qualitative comparison of image quality, three readers independently assessed the two sets of diffusion-weighted (DW) images. To evaluate geometric distortion, a comparison was made between lesion lengths derived from contrast enhanced MR (CE-MR) images and those obtained from the corresponding DW images. For assessment of image parameters, signal-to-noise ratio (SNR), lesion contrast, and contrast-to-noise ratio (CNR) were calculated. The rs-EPI was superior to ss-EPI in most criteria regarding the qualitative image quality. Anatomical structure distinction, delineation of the lesion, ghosting artifact, and overall image quality were significantly better in rs-EPI. Regarding the geometric distortion, lesion length on ss-EPI was significantly different from that of CE-MR, whereas there were no significant differences between CE-MR and rs-EPI. The rs-EPI was superior to ss-EPI in SNR and CNR. Readout-segmented EPI is superior to ss-EPI in the aspect of image quality in DW MR imaging of the breast

Electromyographic Patterns during Golf Swing: Activation Sequence Profiling and Prediction of Shot Effectiveness.

Science.gov (United States)

Verikas, Antanas; Vaiciukynas, Evaldas; Gelzinis, Adas; Parker, James; Olsson, M Charlotte

2016-04-23

This study analyzes muscle activity, recorded in an eight-channel electromyographic (EMG) signal stream, during the golf swing using a 7-iron club and exploits information extracted from EMG dynamics to predict the success of the resulting shot. Muscles of the arm and shoulder on both the left and right sides, namely flexor carpi radialis, extensor digitorum communis, rhomboideus and trapezius, are considered for 15 golf players (∼5 shots each). The method using Gaussian filtering is outlined for EMG onset time estimation in each channel and activation sequence profiling. Shots of each player revealed a persistent pattern of muscle activation. Profiles were plotted and insights with respect to player effectiveness were provided. Inspection of EMG dynamics revealed a pair of highest peaks in each channel as the hallmark of golf swing, and a custom application of peak detection for automatic extraction of swing segment was introduced. Various EMG features, encompassing 22 feature sets, were constructed. Feature sets were used individually and also in decision-level fusion for the prediction of shot effectiveness. The prediction of the target attribute, such as club head speed or ball carry distance, was investigated using random forest as the learner in detection and regression tasks. Detection evaluates the personal effectiveness of a shot with respect to the player-specific average, whereas regression estimates the value of target attribute, using EMG features as predictors. Fusion after decision optimization provided the best results: the equal error rate in detection was 24.3% for the speed and 31.7% for the distance; the mean absolute percentage error in regression was 3.2% for the speed and 6.4% for the distance. Proposed EMG feature sets were found to be useful, especially when used in combination. Rankings of feature sets indicated statistics for muscle activity in both the left and right body sides, correlation-based analysis of EMG dynamics and features

Electromyographic Patterns during Golf Swing: Activation Sequence Profiling and Prediction of Shot Effectiveness

Directory of Open Access Journals (Sweden)

Antanas Verikas

2016-04-01

Full Text Available This study analyzes muscle activity, recorded in an eight-channel electromyographic (EMG signal stream, during the golf swing using a 7-iron club and exploits information extracted from EMG dynamics to predict the success of the resulting shot. Muscles of the arm and shoulder on both the left and right sides, namely flexor carpi radialis, extensor digitorum communis, rhomboideus and trapezius, are considered for 15 golf players (∼5 shots each. The method using Gaussian filtering is outlined for EMG onset time estimation in each channel and activation sequence profiling. Shots of each player revealed a persistent pattern of muscle activation. Profiles were plotted and insights with respect to player effectiveness were provided. Inspection of EMG dynamics revealed a pair of highest peaks in each channel as the hallmark of golf swing, and a custom application of peak detection for automatic extraction of swing segment was introduced. Various EMG features, encompassing 22 feature sets, were constructed. Feature sets were used individually and also in decision-level fusion for the prediction of shot effectiveness. The prediction of the target attribute, such as club head speed or ball carry distance, was investigated using random forest as the learner in detection and regression tasks. Detection evaluates the personal effectiveness of a shot with respect to the player-specific average, whereas regression estimates the value of target attribute, using EMG features as predictors. Fusion after decision optimization provided the best results: the equal error rate in detection was 24.3% for the speed and 31.7% for the distance; the mean absolute percentage error in regression was 3.2% for the speed and 6.4% for the distance. Proposed EMG feature sets were found to be useful, especially when used in combination. Rankings of feature sets indicated statistics for muscle activity in both the left and right body sides, correlation-based analysis of EMG

On-demand generation of background-free single photons from a solid-state source

Science.gov (United States)

Schweickert, Lucas; Jöns, Klaus D.; Zeuner, Katharina D.; Covre da Silva, Saimon Filipe; Huang, Huiying; Lettner, Thomas; Reindl, Marcus; Zichi, Julien; Trotta, Rinaldo; Rastelli, Armando; Zwiller, Val

2018-02-01

True on-demand high-repetition-rate single-photon sources are highly sought after for quantum information processing applications. However, any coherently driven two-level quantum system suffers from a finite re-excitation probability under pulsed excitation, causing undesirable multi-photon emission. Here, we present a solid-state source of on-demand single photons yielding a raw second-order coherence of g(2 )(0 )=(7.5 ±1.6 )×10-5 without any background subtraction or data processing. To this date, this is the lowest value of g(2 )(0 ) reported for any single-photon source even compared to the previously reported best background subtracted values. We achieve this result on GaAs/AlGaAs quantum dots embedded in a low-Q planar cavity by employing (i) a two-photon excitation process and (ii) a filtering and detection setup featuring two superconducting single-photon detectors with ultralow dark-count rates of (0.0056 ±0.0007 ) s-1 and (0.017 ±0.001 ) s-1, respectively. Re-excitation processes are dramatically suppressed by (i), while (ii) removes false coincidences resulting in a negligibly low noise floor.

SunShot Catalyst Prize Competition Fact Sheet

Energy Technology Data Exchange (ETDEWEB)

Solar Energy Technologies Office

2015-04-01

This fact sheet is an overview of the Catalyst Energy Innovation Prize, an open innovation program launched in 2014 by the U.S. Department of Energy SunShot Initiative. This program aims to catalyze the rapid creation and development of products and solutions that address near-term challenges in the U.S. solar energy marketplace.

Three-Level Z-Source Inverters Using a Single LC Impedance Network

DEFF Research Database (Denmark)

Loh, Poh Chiang; Lim, Sok Wei; Gao, Feng

2007-01-01

two LC impedance networks and two isolated dc sources, which can significantly increase the overall system cost and require a more complex modulator for balancing the network inductive voltage boosting. Offering a number of less costly alternatives, this letter presents the design and control of two...... three-level Z-source inverters, whose output voltage can be stepped down or up using only a single LC impedance network connected between the dc input source and either a neutral-point-clamped (NPC) or dc-link cascaded inverter circuitry. Through careful design of their modulation scheme, both inverters...

Flu Shots, Mammogram, and the Perception of Probabilities

NARCIS (Netherlands)

Carman, K.G.; Kooreman, P.

2010-01-01

We study individuals’ decisions to decline or accept preventive health care interventions such as flu shots and mammograms. In particular, we analyze the role of perceptions of the effectiveness of the intervention, by eliciting individuals' subjective probabilities of sickness and survival, with

Differential diagnosis of pituitary adenomas and Rathke's cleft cysts by diffusion-weighted MRI using single-shot fast spin echo technique

Energy Technology Data Exchange (ETDEWEB)

Abe, Takumi; Izumiyama, Hitoshi; Fukuda, Ataru; Tanioka, Daisuke; Kunii, Norihiko; Komatsu, Daisuke; Fujita, Shogo; Ukisu, Ryutaro; Moritani, Toshio [Showa Univ., Tokyo (Japan). School of Medicine

2002-09-01

The purpose of the present study was to prospectively evaluate the diagnostic ability of diffusion-weighted magnetic resonance imaging (DWI) using single-shot fast spin echo (SSFSE) technique to discriminate pituitary adenomas from Rathke's cleft cysts. DWIs were obtained from 40 patients with pathologically proven pituitary macroadenomas and 15 patients with proven Rathke's cleft cysts. Pituitary adenomas were divided into 27 cases with solid components alone, five with non-hemorrhagic large cysts, and eight with intratumoral hemorrhage. On SSFSE DWI, solid components of pituitary adenomas revealed iso or slightly increased intensity and intratumoral hemorrhage showed higher intensity than normal brain parenchyma, whereas Rathke's cleft cysts and intratumoral cysts demonstrated very low intensity. SSFSE DWI did not display the susceptibility artifacts that are seen close to the skull base and sinonasal cavities on echo planar diffusion imaging. On the basis of our preliminary findings, DWI may enable us to differentiate pituitary adenomas with only solid components and hemorrhagic pituitary adenomas appearing hyperintense on T1-weighted images from Rathke's cleft cysts without administration of gadolinium-DTPA. SSFSE DWI appears to be a useful technique for characterizing pituitary diseases without the susceptibility artifacts. Our study is the first report to demonstrate the identification of pituitary disorders on SSFSE DWI. (author)

All-periodically poled, high-power, continuous-wave, single-frequency tunable UV source.

Science.gov (United States)

Aadhi, A; Chaitanya N, Apurv; Jabir, M V; Singh, R P; Samanta, G K

2015-01-01

We report on experimental demonstration of an all-periodically poled, continuous-wave (CW), high-power, single-frequency, ultra-violet (UV) source. Based on internal second-harmonic-generation (SHG) of a CW singly resonant optical parametric oscillator (OPO) pumped in the green, the UV source provides tunable radiation across 398.94-417.08 nm. The compact source comprising of a 25-mm-long MgO-doped periodically poled stoichiometric lithium tantalate (MgO:sPPLT) crystal of period Λ(SLT)=8.5  μm for OPO and a 5-mm-long, multi-grating (Λ(KTP)=3.3, 3.4, 3.6 and 3.8 μm), periodically poled potassium titanium phosphate (PPKTP) for intra-cavity SHG, provides as much as 336 mW of UV power at 398.94 nm, corresponding to a green-to-UV conversion efficiency of ∼6.7%. In addition, the singly resonant OPO (SRO) provides 840 mW of idler at 1541.61 nm and substantial signal power of 108 mW at 812.33 nm transmitted through the high reflective cavity mirrors. UV source provides single-frequency radiation with instantaneous line-width of ∼18.3  MHz and power >100  mW in Gaussian beam profile (ellipticity >92%) across the entire tuning range. Access to lower UV wavelengths requires smaller grating periods to compensate high phase-mismatch resulting from high material dispersion in the UV wavelength range. Additionally, we have measured the normalized temperature and spectral acceptance bandwidth of PPKTP crystal in the UV wavelength range to be ∼2.25°C·cm and ∼0.15  nm·cm, respectively.

Laser Shot Peening System Final Report CRADA No. TC-1369-96

Energy Technology Data Exchange (ETDEWEB)

Stuart, B. C. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Harris, F. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

2017-09-27

This CRADA project was established with a primary goal to develop a laser shot peening system which could operate at production throughput rates and produce the desired depth and intensity of induced shots. The first objective was to understand all parameters required for acceptable peening, including pulse energy, pulse temporal format, pulse spatial format, sample configuration and tamping mechanism. The next objective was to demonstrate the technique on representative samples and then on representative parts. The final objective was to implement the technology into a meaningful industrial peen.

Laser interaction with matter as a source of U.V. and soft X-ray radiation: application to X-ray cinematography

International Nuclear Information System (INIS)

Tonon, G.F.; Colombant, Denis; Delmare, Claude; Rabeau, Maxime

A new detecting device is described. It allows one to get the frequency, the time and space resolution of pictures of U.V. and soft X ray emission of a laser created plasma in a single shot: X ray pictures of such a plasma are presented. After these preliminary results, it is possible to set up readily an X ray framing camera. A laser created plasma is an X ray source of special interest: the emitted power can be 10% of the laser intensity and the emitted spectrum is centered around 1A wavelength [fr

Piling up technology of goods irradiated by single plate source

International Nuclear Information System (INIS)

Xia Hezhou; Chen Yuxia; Cao Hongyun; Lin Yong; Zhou guoquan

1999-01-01

In the irradiation process of piling up goods in static state, four irradiation working sites and single plate source was adopted. The results showed that piling up in this way remarkably raised the irradiation quality of goods. The utilization rate of radioactive ray reached 22.27%

Controlling light emission from single-photon sources using photonic nanowires

DEFF Research Database (Denmark)

Gregersen, Niels; Chen, Yuntian; Mørk, Jesper

2012-01-01

The photonic nanowire has recently emerged as an promising alternative to microcavity-based single-photon source designs. In this simple structure, a geometrical effect ensures a strong coupling between an embedded emitter and the optical mode of interest and a combination of tapers and mirrors a...

SnapShot: O-Glycosylation Pathways across Kingdoms

DEFF Research Database (Denmark)

Joshi, Hiren J.; Narimatsu, Yoshiki; Schjoldager, Katrine T.

2018-01-01

O-glycosylation is one of the most abundant and diverse types of post-translational modifications of proteins. O-glycans modulate the structure, stability, and function of proteins and serve generalized as well as highly specific roles in most biological processes. This ShapShot presents types of......-glycans found in different organisms and their principle biosynthetic pathways...

High frequency measurements of shot noise suppression in atomic-scale metal contacts

Science.gov (United States)

Wheeler, Patrick J.; Evans, Kenneth; Russom, Jeffrey; King, Nicholas; Natelson, Douglas

2009-03-01

Shot noise provides a means of assessing the number and transmission coefficients of transmitting channels in atomic- and molecular-scale junctions. Previous experiments at low temperatures in metal and semiconductor point contacts have demonstrated the expected suppression of shot noise when junction conductance is near an integer multiple of the conductance quantum, G0≡2e^2/h. Using high frequency techniques, we demonstrate the high speed acquisition of such data at room temperature in mechanical break junctions. In clean Au contacts conductance histograms with clear peaks at G0, 2G0, and 3G0 are acquired within hours, and histograms of simultaneous measurements of the shot noise show clear suppression at those conductance values. We describe the dependence of the noise on bias voltage and analyze the noise vs. conductance histograms in terms of a model that averages over transmission coefficients.

Are medical treatments for individuals and groups like single-play and multiple-play gambles?

Directory of Open Access Journals (Sweden)

Michael L. DeKay

2006-11-01

Full Text Available People are often more likely to accept risky monetary gambles with positive expected values when the gambles will be played more than once. We investigated whether this distinction between single-play and multiple-play gambles extends to medical treatments for individual patients and groups of patients. Resident physicians and medical students (extit{n} = 69 and undergraduates (extit{n} = 99 ranked 9 different flu shots and a no-flu-shot option in 1 of 4 combinations of perspective (individual patient vs. group of 1000 patients and uncertainty frame (probability vs. frequency. The rank of the no-flu-shot option (a measure of preference for treatment vs. no treatment was not significantly related to perspective or participant population. The main effect of uncertainty frame and the interaction between perspective and uncertainty frame approached significance (0.1 {extgreater} extit{p} {extgreater} 0.05, with the no-flu-shot option faring particularly poorly (treatment faring particularly well when decisions about many patients were based on frequency information. Undergraduate participants believed that the no-flu-shot option would be less attractive (treatment would be more attractive in decisions about many patients, but these intuitions were inconsistent with the actual ranks. These results and those of other studies suggest that medical treatments for individuals and groups are not analogous to single-play and multiple-play monetary gambles, perhaps because many people are unwilling to aggregate treatment outcomes over patients in the same way that they would compute net gains or losses over monetary gambles.

Empathy in One-Shot Prisoner Dilemma

OpenAIRE

Rossi, Giulia; Tcheukam, Alain; Tembine, Hamidou

2017-01-01

Strategic decision making involves affective and cognitive functions like reasoning, cognitive and emotional empathy which may be subject to age and gender differences. However, empathy-related changes in strategic decision-making and their relation to age, gender and neuropsychological functions have not been studied widely. In this article, we study a one-shot prisoner dilemma from a psychological game theory viewpoint. Forty seven participants (28 women and 19 men), aged 18 to 42 years, we...

Extraction of Pn seismic signals from air-gun shots recorded by the Cascadia Amphibious seismic experiment

Science.gov (United States)

Rathnayaka, S.; Gao, H.

2017-12-01

The goal of this study is to extract Pn (head wave) seismic waveforms recorded by both offshore and onshore (broadband and short period) seismic stations and evaluate the data quality. Two offshore active-source seismic experiments, MGL 1211 and MGL 1212, were conducted from 13th June to 24th July 2012, during the first year deployment of the Cascadia Initiative Amphibious Array. In total, we choose 110 ocean bottom seismometers and 209 inland stations that are located along the entire Cascadia subduction zone. We first remove the instrument response, and then explore the potential frequency ranges and the diurnal effect. We make the common receiver gathering for each seismic station and filter the seismic waveforms at multiple frequency bands, ranging from 3-5 Hz, 5-10 Hz, 10-20 Hz, to 20-40 Hz, respectively. To quantitatively evaluate the data quality, we calculate the signal-to-noise ratio (SNR) of the waveforms for usable stations that record clear Pn arrivals at multiple frequency bands. Our results show that most offshore stations located at deep water (>1.5 km) record clear air-gun shot signals at frequencies higher than 3 Hz and up to 550 km away from the source. For most stations located on the shallow continental shelf, the seismic recordings appear much noisier at all the frequencies compared to stations at deep water. Three general trends are observed for the SNR distribution; First, the SNR ratio increases from lower to higher frequency bands; Second, the ratio decreases with the increasing source-to-receiver distance; And third, the ratio increases from shallow to deep water. We also observe a rough negative relationship of the signal-to-noise ratio with the thickness of the marine sediment. Only 5 inland stations record clear air-gun shot arrivals up to 200 km away from the source. More detailed data quality analysis with more results will also be present.

Cross-correlation measurement of quantum shot noise using homemade transimpedance amplifiers

International Nuclear Information System (INIS)

Hashisaka, Masayuki; Ota, Tomoaki; Yamagishi, Masakazu; Fujisawa, Toshimasa; Muraki, Koji

2014-01-01

We report a cross-correlation measurement system, based on a new approach, which can be used to measure shot noise in a mesoscopic conductor at milliKelvin temperatures. In contrast to other measurement systems in which high-speed low-noise voltage amplifiers are commonly used, our system employs homemade transimpedance amplifiers (TAs). The low input impedance of the TAs significantly reduces the crosstalk caused by unavoidable parasitic capacitance between wires. The TAs are designed to have a flat gain over a frequency band from 2 kHz to 1 MHz. Low-noise performance is attained by installing the TAs at a 4 K stage of a dilution refrigerator. Our system thus fulfills the technical requirements for cross-correlation measurements: low noise floor, high frequency band, and negligible crosstalk between two signal lines. Using our system, shot noise generated at a quantum point contact embedded in a quantum Hall system is measured. The good agreement between the obtained shot-noise data and theoretical predictions demonstrates the accuracy of the measurements

Comparison of Time-of-flight and Multicollector ICP Mass Spectrometers for Measuring Actinides in Small Samples using single shot Laser Ablation

International Nuclear Information System (INIS)

R.S. Houk; D.B. Aeschliman; S.J. Bajic; D. Baldwin

2005-01-01

ability to provide good detection limits for single laser shots is critical

Experimental and Numerical Analysis of Microstructures and Stress States of Shot-Peened GH4169 Superalloys

Science.gov (United States)

Hu, Dianyin; Gao, Ye; Meng, Fanchao; Song, Jun; Wang, Rongqiao

2018-04-01

Combining experiments and finite element analysis (FEA), a systematic study was performed to analyze the microstructural evolution and stress states of shot-peened GH4169 superalloy over a variety of peening intensities and coverages. A dislocation density evolution model was integrated into the representative volume FEA model to quantitatively predict microstructural evolution in the surface layers and compared with experimental results. It was found that surface roughness and through-depth residual stress profile are more sensitive to shot-peening intensity compared to coverage due to the high kinetic energy involved. Moreover, a surface nanocrystallization layer was discovered in the top surface region of GH4169 for all shot-peening conditions. However, the grain refinement was more intensified under high shot-peening coverage, under which enough time was permitted for grain refinement. The grain size gradient predicted by the numerical framework showed good agreement with experimental observations.

77 FR 38070 - Office of Refugee Resettlement; Announcing the Award of a Single-Source Program Expansion...

Science.gov (United States)

2012-06-26

....676] Office of Refugee Resettlement; Announcing the Award of a Single- Source Program Expansion... (BCFS) in San Antonio, TX AGENCY: Office of Refugee Resettlement, ACF, HHS. ACTION: The Office of Refugee Resettlement announces the award of a single-source program expansion supplement grant from its...

Micro-MID Manufacturing By Two-Shot Injection Moulding

DEFF Research Database (Denmark)

Islam, Mohammad Aminul; Hansen, Hans Nørgaard; Tang, Peter Torben

2008-01-01

a specific MID process chain is used for micro products, many technical challenges are encountered which would not be problems for macro scale products. This paper investigates on a specific MID process chain (two shot moulding) and discusses the technical difficulties associated with the production process...

A Gene Family Coding for Salivary Proteins (SHOT) of the Polyphagous Spider Mite Tetranychus urticae Exhibits Fast Host-Dependent Transcriptional Plasticity.

Science.gov (United States)

Jonckheere, Wim; Dermauw, Wannes; Khalighi, Mousaalreza; Pavlidi, Nena; Reubens, Wim; Baggerman, Geert; Tirry, Luc; Menschaert, Gerben; Kant, Merijn R; Vanholme, Bartel; Van Leeuwen, Thomas

2018-01-01

The salivary protein repertoire released by the herbivorous pest Tetranychus urticae is assumed to hold keys to its success on diverse crops. We report on a spider mite-specific protein family that is expanded in T. urticae. The encoding genes have an expression pattern restricted to the anterior podocephalic glands, while peptide fragments were found in the T. urticae secretome, supporting the salivary nature of these proteins. As peptide fragments were identified in a host-dependent manner, we designated this family as the SHOT (secreted host-responsive protein of Tetranychidae) family. The proteins were divided in three groups based on sequence similarity. Unlike TuSHOT3 genes, TuSHOT1 and TuSHOT2 genes were highly expressed when feeding on a subset of family Fabaceae, while expression was depleted on other hosts. TuSHOT1 and TuSHOT2 expression was induced within 24 h after certain host transfers, pointing toward transcriptional plasticity rather than selection as the cause. Transfer from an 'inducer' to a 'noninducer' plant was associated with slow yet strong downregulation of TuSHOT1 and TuSHOT2, occurring over generations rather than hours. This asymmetric on and off regulation points toward host-specific effects of SHOT proteins, which is further supported by the diversity of SHOT genes identified in Tetranychidae with a distinct host repertoire.

Synthesis of anisotropic CdS nanostructures via a single-source route

CSIR Research Space (South Africa)

Rajasekhar Pullabhotla, VSR

2011-02-01

Full Text Available A cadmium tetrahydroisoquinoline dithiocarbamate (DTC) complex has been used as single-source precursor for the synthesis of highly faceted hexadecylamine (HDA) capped CdS nanoparticles. Hexagonal and close to cubic shaped particles with distinct...

Multifragmentation of a very heavy nuclear system (I): selection of single-source events

Energy Technology Data Exchange (ETDEWEB)

Frankland, J.D.; Bacri, Ch.O.; Borderie, B. [Paris-11 Univ., Inst. de Physique Nucleaire, 91 - Orsay (France)] [and others

2000-07-01

A sample of 'single-source' events, compatible with the multifragmentation of very heavy fused systems, are isolated among well-measured {sup 155}Gd + {sup nat}U 36 A.MeV reactions by examining the evolution of the kinematics of fragments with Z {>=} 5 as a function of the dissipated energy and loss of memory of the entrance channel. Single-source events are found to be the result of very central collisions. Such central collisions may also lead to multiple fragment emission due to the decay of excited projectile- and target-like nuclei and so-called 'neck' emission, and for this reason the isolation of single-source events is very difficult. Event-selection criteria based on centrality of collisions, or on the isotropy of the emitted fragments in each event, are found to be inefficient to separate the two mechanisms, unless they take into account the redistribution of fragments' kinetic energies into directions perpendicular to the beam axis. The selected events are good candidates to look for bulk effects in the multifragmentation process. (authors)

Multifragmentation of a very heavy nuclear system (I): selection of single-source events

International Nuclear Information System (INIS)

Frankland, J.D.; Bacri, Ch.O.; Borderie, B.; Rivet, M.F.; Squalli, M.; Auger, G.; Bellaize, N.; Bocage, F.; Bougault, R.; Brou, R.; Buchet, Ph.; Chbihi, A.; Colin, J.; Cussol, D.; Dayras, R.; Demeyer, A.; Dore, D.; Durand, D.; Galichet, E.; Genouin-Duhamel, E.; Gerlic, E.; Guinet, D.; Lautesse, Ph.; Laville, J.L.; Lecolley, J.F.; Legrain, R.; Le Neindre, N.; Lopez, O.; Louvel, M.; Maskay, A.M.; Nalpas, L.; Nguyen, A.D.; Parlog, M.; Peter, J.; Plagnol, E.; Rosato, E.; Saint-Laurent, F.; Salou, S.; Steckmeyer, J.C.; Stern, M.; Tabacaru, G.; Tamain, B.; Tirel, O.; Tassan-Got, L.; Vient, E.; Volant, C.; Wieleczko, J.P.

2001-01-01

A sample of 'single-source' events, compatible with the multifragmentation of very heavy fused systems, are isolated among well-measured 155 Gd+ nat U 36 A MeV reactions by examining the evolution of the kinematics of fragments with Z≥5 as a function of the dissipated energy and loss of memory of the entrance channel. Single-source events are found to be the result of very central collisions. Such central collisions may also lead to multiple fragment emission due to the decay of excited projectile- and target-like nuclei and so-called 'neck' emission, and for this reason the isolation of single-source events is very difficult. Event-selection criteria based on centrality of collisions, or on the isotropy of the emitted fragments in each event, are found to be inefficient to separate the two mechanisms, unless they take into account the redistribution of fragments' kinetic energies into directions perpendicular to the beam axis. The selected events are good candidates to look for bulk effects in the multifragmentation process

Towards radiocarbon dating of single foraminifera with a gas ion source

Science.gov (United States)

Wacker, L.; Lippold, J.; Molnár, M.; Schulz, H.

2013-01-01

Carbonate shells from foraminifera are often analysed for radiocarbon to determine the age of deep-sea sediments or to assess radiocarbon reservoir ages. However, a single foraminiferal test typically contains only a few micrograms of carbon, while most laboratories require more than 100 μg for radiocarbon dating with an accelerator mass spectrometry (AMS) system. The collection of the required amount of foraminifera for a single analyses is therefore time consuming and not always possible. Here, we present a convenient method to measure the radiocarbon content of foraminifera using an AMS system fitted with a gas ion source. CO2 is liberated from 150 to 1150 μg of carbonate in septum sealed vials by acid decomposition of the carbonate. The CO2 is collected on a zeolite trap and subsequently transferred to a syringe from where it is delivered to the ion source. A sample of 400 μg (50 μg C) typically gives a 12C- ion source current of 10-15 μA over 20 min, yielding a measurement precision of less than 7 per mil for a modern sample. Using this method, we were able to date a single 560 μg Cibicides pseudoungerianus test at 14,030 ± 160 radiocarbon years. Only a minor modification to our existing gas handling system was required and the system is fully automatable to further reduce the effort involved for sample preparation.

Towards radiocarbon dating of single foraminifera with a gas ion source

International Nuclear Information System (INIS)

Wacker, L.; Lippold, J.; Molnár, M.; Schulz, H.

2013-01-01

Carbonate shells from foraminifera are often analysed for radiocarbon to determine the age of deep-sea sediments or to assess radiocarbon reservoir ages. However, a single foraminiferal test typically contains only a few micrograms of carbon, while most laboratories require more than 100 μg for radiocarbon dating with an accelerator mass spectrometry (AMS) system. The collection of the required amount of foraminifera for a single analyses is therefore time consuming and not always possible. Here, we present a convenient method to measure the radiocarbon content of foraminifera using an AMS system fitted with a gas ion source. CO 2 is liberated from 150 to 1150 μg of carbonate in septum sealed vials by acid decomposition of the carbonate. The CO 2 is collected on a zeolite trap and subsequently transferred to a syringe from where it is delivered to the ion source. A sample of 400 μg (50 μg C) typically gives a 12 C − ion source current of 10–15 μA over 20 min, yielding a measurement precision of less than 7 per mil for a modern sample. Using this method, we were able to date a single 560 μg Cibicides pseudoungerianus test at 14,030 ± 160 radiocarbon years. Only a minor modification to our existing gas handling system was required and the system is fully automatable to further reduce the effort involved for sample preparation.

Towards radiocarbon dating of single foraminifera with a gas ion source

Energy Technology Data Exchange (ETDEWEB)

Wacker, L., E-mail: wacker@phys.ethz.ch [Laboratory of Ion Beam Physics, ETH Zurich, 8093 Zurich (Switzerland); Lippold, J. [Heidelberg Academy of Sciences, 69120 Heidelberg (Germany); Molnar, M. [Laboratory of Ion Beam Physics, ETH Zurich, 8093 Zurich (Switzerland); Institute of Nuclear Research, Hungarian Academy of Sciences, 4026 Debrecen (Hungary); Schulz, H. [Institute for Geosciencies, University of Tuebingen, 72076 Tuebingen (Germany)

2013-01-15

Carbonate shells from foraminifera are often analysed for radiocarbon to determine the age of deep-sea sediments or to assess radiocarbon reservoir ages. However, a single foraminiferal test typically contains only a few micrograms of carbon, while most laboratories require more than 100 {mu}g for radiocarbon dating with an accelerator mass spectrometry (AMS) system. The collection of the required amount of foraminifera for a single analyses is therefore time consuming and not always possible. Here, we present a convenient method to measure the radiocarbon content of foraminifera using an AMS system fitted with a gas ion source. CO{sub 2} is liberated from 150 to 1150 {mu}g of carbonate in septum sealed vials by acid decomposition of the carbonate. The CO{sub 2} is collected on a zeolite trap and subsequently transferred to a syringe from where it is delivered to the ion source. A sample of 400 {mu}g (50 {mu}g C) typically gives a {sup 12}C{sup -} ion source current of 10-15 {mu}A over 20 min, yielding a measurement precision of less than 7 per mil for a modern sample. Using this method, we were able to date a single 560 {mu}g Cibicides pseudoungerianus test at 14,030 {+-} 160 radiocarbon years. Only a minor modification to our existing gas handling system was required and the system is fully automatable to further reduce the effort involved for sample preparation.

Color-SIFT model: a robust and an accurate shot boundary detection algorithm

Science.gov (United States)

Sharmila Kumari, M.; Shekar, B. H.

2010-02-01

In this paper, a new technique called color-SIFT model is devised for shot boundary detection. Unlike scale invariant feature transform model that uses only grayscale information and misses important visual information regarding color, here we have adopted different color planes to extract keypoints which are subsequently used to detect shot boundaries. The basic SIFT model has four stages namely scale-space peak selection, keypoint localization, orientation assignment and keypoint descriptor and all these four stages were employed to extract key descriptors in each color plane. The proposed model works on three different color planes and a fusion has been made to take a decision on number of keypoint matches for shot boundary identification and hence is different from the color global scale invariant feature transform that works on quantized images. In addition, the proposed algorithm possess invariance to linear transformation and robust to occlusion and noisy environment. Experiments have been conducted on the standard TRECVID video database to reveal the performance of the proposed model.

IMPACT OF SHOTS ON FINAL SCORE OF A FOOTBALL MATCH

Directory of Open Access Journals (Sweden)

Miroslav Radoman

2008-08-01

Full Text Available The research has been done on a sample of 64 played games on the World championship FIFA, World Cup Germany 2006 and 128 results of the games divided in three integrals according to the score (win, defeat and unresolved score . The analysis is done according to the total number of shots during the game. Considering the results that are got and their interpretations, we could conclude that the results of data analysis in which is used the multi-method of MANOVA analysis and discriminative analysis, has shown that there are significant difference in frequency of the games result (win, defeat or unresolved score in shots element during the game. Even thou the noticed difference in frequency are not equally expressed, the results that are got have insinuated that there are significant differences in followed elements of the football game. Implemented analysis (royev test i T-test have confirmed that in every analyzed elements of the shot there are statistically significant differences in the result of the game (win, defeat, unresolved score and that the differences in shot’s elements are consequence different selection of the tactics and techniques also the ability of their realization in the stage of at tack and defense.

Who Takes Advantage of Free Flu Shots? Examining the Effects of an Expansion in Coverage

NARCIS (Netherlands)

Carman, K.G.; Mosca, I.

2011-01-01

Because of the high risk of costly complications (including death) and the externalities of contagious diseases, many countries provide free flu shots to certain populations free of charge. This paper examines the expansion of the free flu shot program in the Netherlands. This program expanded in

Calibrate the aerial surveying instrument by the limited surface source and the single point source that replace the unlimited surface source

CERN Document Server

Lu Cun Heng

1999-01-01

It is described that the calculating formula and surveying result is found on the basis of the stacking principle of gamma ray and the feature of hexagonal surface source when the limited surface source replaces the unlimited surface source to calibrate the aerial survey instrument on the ground, and that it is found in the light of the exchanged principle of the gamma ray when the single point source replaces the unlimited surface source to calibrate aerial surveying instrument in the air. Meanwhile through the theoretical analysis, the receiving rate of the crystal bottom and side surfaces is calculated when aerial surveying instrument receives gamma ray. The mathematical expression of the gamma ray decaying following height according to the Jinge function regularity is got. According to this regularity, the absorbing coefficient that air absorbs the gamma ray and the detective efficiency coefficient of the crystal is calculated based on the ground and air measuring value of the bottom surface receiving cou...

Control of lead solubility in soil contaminated with lead shot: Effect of soil pH

International Nuclear Information System (INIS)

Rooney, Corinne P.; McLaren, Ronald G.; Condron, Leo M.

2007-01-01

An incubation experiment was carried out to assess the rate of oxidation of Pb shot and subsequent transfer of Pb to the soil under a range of soil pH conditions. Lead shot corrosion was rapid, so that soil solution and fine earth ( 3 (CO 3 ) 2 (OH) 2 ), developed in crusts surrounding individual Pb pellets. However, irrespective of pH, Pb 2+ activities in the soil solutions, modelled using WHAM 6, were much lower than would be the case if they were controlled by the solubility of the dominant Pb compounds present in the Pb shot crust material. In contrast, modelling of soil solid-solution phase distribution of Pb, again using WHAM 6, suggested that, at least during the 24 months of the study, soil solution Pb concentrations were more likely to be controlled by sorption of Pb by the soil solid phase. - Sorption processes control Pb 2+ ion activity in soils contaminated with Pb shot

On-demand semiconductor single-photon source with near-unity indistinguishability.

Science.gov (United States)

He, Yu-Ming; He, Yu; Wei, Yu-Jia; Wu, Dian; Atatüre, Mete; Schneider, Christian; Höfling, Sven; Kamp, Martin; Lu, Chao-Yang; Pan, Jian-Wei

2013-03-01

Single-photon sources based on semiconductor quantum dots offer distinct advantages for quantum information, including a scalable solid-state platform, ultrabrightness and interconnectivity with matter qubits. A key prerequisite for their use in optical quantum computing and solid-state networks is a high level of efficiency and indistinguishability. Pulsed resonance fluorescence has been anticipated as the optimum condition for the deterministic generation of high-quality photons with vanishing effects of dephasing. Here, we generate pulsed single photons on demand from a single, microcavity-embedded quantum dot under s-shell excitation with 3 ps laser pulses. The π pulse-excited resonance-fluorescence photons have less than 0.3% background contribution and a vanishing two-photon emission probability. Non-postselective Hong-Ou-Mandel interference between two successively emitted photons is observed with a visibility of 0.97(2), comparable to trapped atoms and ions. Two single photons are further used to implement a high-fidelity quantum controlled-NOT gate.

Heat transfer and velocity characteristics of single- and two-phase flows in a subsonic model gun

International Nuclear Information System (INIS)

Bicen, A.F.; Khezzar, L.; Schmidt, M.; Whitelaw, J.H.

1989-01-01

Heat transfer and velocity measurements are reported for single- and two-phase flows in the wake of an in-bore projectile propelled by an inert gas at an initial gauge pressure of 8 bars to an exit velocity over 40 m/s in ∼ 33 ms. The results show that with the single phase the turbulent velocity boundary layers occupy over 20% of the barrel radius and that the wall heat transfer increases with distance from the breech and decreases with time during the shot. In the initial chamber, and later in the shot, the heat transfer results are close to those obtained from a convection correlation for a steady turbulent boundary layer, contrary to those at locations swept by the projectile, which are higher by up to 50% throughout the shot. The two-phase flow results show that 55-μm particles with loadings of 1.3% and 4% by volume initially lag the fluid and this lag increases with distance from the breech. Later in the shot the particles catch up and lead the decelerating fluid by an amount that is greater, with the higher particle loading and with a tendency for the particle velocity to increase around the edge of the boundary layer

Estimation of post disruption plasma temperature for fast current quench Aditya plasma shots

International Nuclear Information System (INIS)

Purohit, S.; Chowdhuri, M.B.; Joisa, Y.S.; Raval, J.V.; Ghosh, J.; Jha, R.

2013-01-01

Characteristics of tokamak current quenches are an important issue for the determination of electromagnetic forces that act on the in-vessel components and vacuum vessel during major disruptions. It is observed that thermal quench is followed by a sharp current decay. Fast current quench disruptive plasma shots were investigated for ADITYA tokamak. The current decay time was determined for the selected shots, which were in the range of 0.8 msec to 2.5 msec. This current decay information was then applied to L/R model, frequently employed for the estimation of the current decay time in tokamak plasmas, considering plasma inductance and plasma resistivity. This methodology was adopted for the estimation of the post disruption plasma temperature using the experimentally observed current decay time for the fast current quench disruptive ADITYA plasma shots. The study reveals that for the identified shots there is a constant increase in the current decay time with the post disruption plasma temperature. The investigations also explore the behavior post disruption plasma temperature and the current decay time as a function of the edge safety factor, Q. Post disruption plasma temperature and the current decay time exhibits a decrease with the increase in the value Q. (author)

Ionization dual-zone static detector having single radioactive source

International Nuclear Information System (INIS)

Ried, L. Jr.; Wade, A.L.

1977-01-01

This ionization detector or combustion product detector includes a single radioactive source located in an ionization chamber, and the ionization chamber includes portions comprising a reference zone and a signal zone. Electrical circuitry connected to the reference and signal zones provides an output signal directly related to changes in voltages across the signal zone in relation to the amount of particulates of combustion present in the ionization chamber

Creation and recovery of a W(111) single atom gas field ion source

International Nuclear Information System (INIS)

Pitters, Jason L.; Urban, Radovan; Wolkow, Robert A.

2012-01-01

Tungsten single atom tips have been prepared from a single crystal W(111) oriented wire using the chemical assisted field evaporation and etching method. Etching to a single atom tip occurs through a symmetric structure and leads to a predictable last atom unlike etching with polycrystalline tips. The single atom tip formation procedure is shown in an atom by atom removal process. Rebuilds of single atom tips occur on the same crystalline axis as the original tip such that ion emission emanates along a fixed direction for all tip rebuilds. This preparation method could be utilized and developed to prepare single atom tips for ion source development.

Highly efficient electron gun with a single-atom electron source

International Nuclear Information System (INIS)

Ishikawa, Tsuyoshi; Urata, Tomohiro; Cho, Boklae; Rokuta, Eiji; Oshima, Chuhei; Terui, Yoshinori; Saito, Hidekazu; Yonezawa, Akira; Tsong, Tien T.

2007-01-01

The authors have demonstrated highly collimated electron-beam emission from a practical electron gun with a single-atom electron source; ∼80% of the total emission current entered the electron optics. This ratio was two or three orders of magnitude higher than those of the conventional electron sources such as a cold field emission gun and a Zr/O/W Schottky gun. At the pressure of less than 1x10 -9 Pa, the authors observed stable emission of 20 nA, which generates the specimen current of 5 pA required for scanning electron microscopes

Opening Shots and Loose Slots: adapting Las Vegas

NARCIS (Netherlands)

Goggin, J.

2015-01-01

Anyone who has ever seen a film set in Las Vegas will be familiar with opening shots of sensational neon signage clustered against the night sky. This montage sequence, now an established convention, leads the viewer on a thrilling joy-ride, generally beginning on Fremont Street in the old city

Diffusion tensor trace mapping in normal adult brain using single-shot EPI technique: A methodological study of the aging brain

International Nuclear Information System (INIS)

Chen, Z.G.; Hindmarsh, T.; Li, T.Q.

2001-01-01

Purpose: To quantify age-related changes of the average diffusion coefficient value in normal adult brain using orientation-independent diffusion tensor trace mapping and to address the methodological influences on diffusion quantification. Material and Methods: Fifty-four normal subjects (aged 20-79 years) were studied on a 1.5-T whole-body MR medical unit using a diffusion-weighted single-shot echo-planar imaging technique. Orientation-independent diffusion tensor trace maps were constructed for each subject using diffusion-weighted MR measurements in four different directions using a tetrahedral gradient combination pattern. The global average (including cerebral spinal fluid) and the tissue average of diffusion coefficients in adult brains were determined by analyzing the diffusion coefficient distribution histogram for the entire brain. Methodological influences on the measured diffusion coefficient were also investigated by comparing the results obtained using different experimental settings. Results: Both global and tissue averages of the diffusion coefficient are significantly correlated with age (p<0.03). The global average of the diffusion coefficient increases 3% per decade after the age of 40, whereas the increase in the tissue average of diffusion coefficient is about 1% per decade. Experimental settings for self-diffusion measurements, such as data acquisition methods and number of b-values, can slightly influence the statistical distribution histogram of the diffusion tensor trace and its average value. Conclusion: Increased average diffusion coefficient in adult brains with aging are consistent with findings regarding structural changes in the brain that have been associated with aging. The study also demonstrates that it is desirable to use the same experimental parameters for diffusion coefficient quantification when comparing between different subjects and groups of interest

A single-phase embedded Z-source DC-AC inverter.

Science.gov (United States)

Kim, Se-Jin; Lim, Young-Cheol

2014-01-01

In the conventional DC-AC inverter consisting of two DC-DC converters with unipolar output capacitors, the output capacitor voltages of the DC-DC converters must be higher than the DC input voltage. To overcome this weakness, this paper proposes a single-phase DC-AC inverter consisting of two embedded Z-source converters with bipolar output capacitors. The proposed inverter is composed of two embedded Z-source converters with a common DC source and output AC load. Though the output capacitor voltages of the converters are relatively low compared to those of a conventional inverter, an equivalent level of AC output voltages can be obtained. Moreover, by controlling the output capacitor voltages asymmetrically, the AC output voltage of the proposed inverter can be higher than the DC input voltage. To verify the validity of the proposed inverter, experiments were performed with a DC source voltage of 38 V. By controlling the output capacitor voltages of the converters symmetrically or asymmetrically, the proposed inverter can produce sinusoidal AC output voltages. The experiments show that efficiencies of up to 95% and 97% can be achieved with the proposed inverter using symmetric and asymmetric control, respectively.

Gearbox Fault Diagnosis in a Wind Turbine Using Single Sensor Based Blind Source Separation

Directory of Open Access Journals (Sweden)

Yuning Qian

2016-01-01

Full Text Available This paper presents a single sensor based blind source separation approach, namely, the wavelet-assisted stationary subspace analysis (WSSA, for gearbox fault diagnosis in a wind turbine. Continuous wavelet transform (CWT is used as a preprocessing tool to decompose a single sensor measurement data into a set of wavelet coefficients to meet the multidimensional requirement of the stationary subspace analysis (SSA. The SSA is a blind source separation technique that can separate the multidimensional signals into stationary and nonstationary source components without the need for independency and prior information of the source signals. After that, the separated nonstationary source component with the maximum kurtosis value is analyzed by the enveloping spectral analysis to identify potential fault-related characteristic frequencies. Case studies performed on a wind turbine gearbox test system verify the effectiveness of the WSSA approach and indicate that it outperforms independent component analysis (ICA and empirical mode decomposition (EMD, as well as the spectral-kurtosis-based enveloping, for wind turbine gearbox fault diagnosis.

Experiments and Analysis of Close-Shot Identification of On-Branch Citrus Fruit with RealSense

Directory of Open Access Journals (Sweden)

Jizhan Liu

2018-05-01

Full Text Available Fruit recognition based on depth information has been a hot topic due to its advantages. However, the present equipment and methods cannot meet the requirements of rapid and reliable recognition and location of fruits in close shot for robot harvesting. To solve this problem, we propose a recognition algorithm for citrus fruit based on RealSense. This method effectively utilizes depth-point cloud data in a close-shot range of 160 mm and different geometric features of the fruit and leaf to recognize fruits with a intersection curve cut by the depth-sphere. Experiments with close-shot recognition of six varieties of fruit under different conditions were carried out. The detection rates of little occlusion and adhesion were from 80–100%. However, severe occlusion and adhesion still have a great influence on the overall success rate of on-branch fruits recognition, the rate being 63.8%. The size of the fruit has a more noticeable impact on the success rate of detection. Moreover, due to close-shot near-infrared detection, there was no obvious difference in recognition between bright and dark conditions. The advantages of close-shot limited target detection with RealSense, fast foreground and background removal and the simplicity of the algorithm with high precision may contribute to high real-time vision-servo operations of harvesting robots.

Shot Noise Suppression in a Quantum Point Contact with Short Channel Length

International Nuclear Information System (INIS)

Jeong, Heejun

2015-01-01

An experimental study on the current shot noise of a quantum point contact with short channel length is reported. The experimentally measured maximum energy level spacing between the ground and the first excited state of the device reached up to 7.5 meV, probably due to the hard wall confinement by using shallow electron gas and sharp point contact geometry. The two-dimensional non-equilibrium shot noise contour map shows noise suppression characteristics in a wide range of bias voltage. Fano factor analysis indicates spin-polarized transport through a short quantum point contact. (paper)

Shot noise enhancement from non-equilibrium plasmons in Luttinger liquid junctions

International Nuclear Information System (INIS)

Kim, Jaeuk U; Kinaret, Jari M; Choi, Mahn-Soo

2005-01-01

We consider a quantum wire double junction system with each wire segment described by a spinless Luttinger model, and study theoretically shot noise in this system in the sequential tunnelling regime. We find that the non-equilibrium plasmonic excitations in the central wire segment give rise to qualitatively different behaviour compared to the case with equilibrium plasmons. In particular, shot noise is greatly enhanced by them, and exceeds the Poisson limit. We show that the enhancement can be explained by the emergence of several current-carrying processes, and that the effect disappears if the channels effectively collapse to one because of fast plasmon relaxation processes, for example