Kontar, E. P.; MacKinnon, A. L.; Schwartz, R. A.; Brown, J. C.
2006-02-01
The observed hard X-ray (HXR) flux spectrum I(ɛ) from solar flares is a combination of primary bremsstrahlung photons I_P(ɛ) with a spectrally modified component from photospheric Compton backscatter of downward primary emission. The latter can be significant, distorting or hiding the true features of the primary spectrum which are key diagnostics for acceleration and propagation of high energy electrons and of their energy budget. For the first time in solar physics, we use a Green's function approach to the backscatter spectral deconvolution problem, constructing a Green's matrix including photoelectric absorption. This approach allows spectrum-independent extraction of the primary spectrum for several HXR flares observed by the Ramaty High Energy Solar Spectroscopic Imager (RHESSI). We show that the observed and primary spectra differ very substantially for flares with hard spectra close to the disk centre. We show in particular that the energy dependent photon spectral index γ (ɛ)=-d log I/d log ɛ is very different for I_P(ɛ) and for I(ɛ) and that inferred mean source electron spectra F(E) differ greatly. Even for a forward fitting of a parametric F(E) to the data, a clear low-energy cutoff required to fit I(ɛ) essentially disappears when the fit is to I_P(ɛ) - i.e. when albedo correction is included. The self-consistent correction for backscattered photons is thus shown to be crucial in determining the energy spectra of flare accelerated electrons, and hence their total number and energy.
Kontar, E P; Schwartz, R A; Brown, J C; Kontar, Eduard P.; Kinnon, Alec L. Mac; Schwartz, Richard A.; Brown, John C.
2006-01-01
The observed hard X-ray (HXR) flux spectrum $I(\\epsilon)$ from solar flares is a combination of primary bremsstrahlung photons $I_P(\\epsilon)$ with a spectrally modified component from photospheric Compton backscatter of downward primary emission. The latter can be significant, distorting or hiding the true features of the primary spectrum which are key diagnostics for acceleration and propagation of high energy electrons and of their energy budget. For the first time in solar physics, we use a Green's function approach to the backscatter spectral deconvolution problem, constructing a Green's matrix including photoelectric absorption. This approach allows spectrum-independent extraction of the primary spectrum for several HXR flares observed by the {\\it Ramaty High Energy Solar Spectroscopic Imager} (RHESSI). We show that the observed and primary spectra differ very substantially for flares with hard spectra close to the disk centre. We show in particular that the energy dependent photon spectral index $\\gamm...
Off-Angle Iris Correction Methods
Energy Technology Data Exchange (ETDEWEB)
Santos-Villalobos, Hector J [ORNL; Thompson, Joseph T [ORNL; Karakaya, Mahmut [ORNL; Boehnen, Chris Bensing [ORNL
2016-01-01
In many real world iris recognition systems obtaining consistent frontal images is problematic do to inexperienced or uncooperative users, untrained operators, or distracting environments. As a result many collected images are unusable by modern iris matchers. In this chapter we present four methods for correcting off-angle iris images to appear frontal which makes them compatible with existing iris matchers. The methods include an affine correction, a retraced model of the human eye, measured displacements, and a genetic algorithm optimized correction. The affine correction represents a simple way to create an iris image that appears frontal but it does not account for refractive distortions of the cornea. The other method account for refraction. The retraced model simulates the optical properties of the cornea. The other two methods are data driven. The first uses optical flow to measure the displacements of the iris texture when compared to frontal images of the same subject. The second uses a genetic algorithm to learn a mapping that optimizes the Hamming Distance scores between off-angle and frontal images. In this paper we hypothesize that the biological model presented in our earlier work does not adequately account for all variations in eye anatomy and therefore the two data-driven approaches should yield better performance. Results are presented using the commercial VeriEye matcher that show that the genetic algorithm method clearly improves over prior work and makes iris recognition possible up to 50 degrees off-angle.
Doppler angle correction in the measurement of intrarenal parameters
Directory of Open Access Journals (Sweden)
Mennitt K
2011-03-01
Full Text Available Jing Gao¹, Keith Hentel¹, Qiang Zhu², Teng Ma², George Shih¹, Kevin Mennitt¹, Robert Min¹¹Department of Radiology, New York Presbyterian Hospital, Weill Cornell Medical College, NY, USA; ²Division of Diagnostic Ultrasound, Department of Radiology, Beijing Tongren Hospital, Capital Medical University, Beijing, ChinaBackground: The aim of this study was to assess differences in intrarenal artery Doppler parameters measured without and with Doppler angle correction.Methods: We retrospectively reviewed color duplex sonography in 30 normally functioning kidneys (20 native kidneys in 10 subjects and 10 transplanted kidneys in 10 subjects performed between January 26, 2010 and July 26, 2010. There were 10 age-matched men and10 age-matched women (mean 39.8 ± 12.2, range 21–60 years in this study. Depending on whether the Doppler angle was corrected in the spectral Doppler measurement, Doppler parameters including peak systolic velocity (PSV, end-diastolic velocity (EDV, and resistive index (RI measured at the interlobar artery of the kidney were divided into two groups, ie, initial Doppler parameters measured without Doppler angle correction (Group 1 and remeasured Doppler parameters with Doppler angle correction (Group 2. Values for PSV, EDV, and RI measured without Doppler angle correction were compared with those measured with Doppler angle correction, and were analyzed statistically with a paired-samples t-test.Results: There were statistical differences in PSV and EDV at the interlobar artery in the upper, mid, and lower poles of the kidney between Group 1 and Group 2 (all P < 0.001. PSV and EDV in Group 1 were significantly lower than in Group 2. RI in Group 1 was the same as that in Group 2 in the upper, mid, and lower poles of the kidneys.Conclusion: Doppler angle correction plays an important role in the accurate measurement of intrarenal blood flow velocity. The true flow velocity converted from the maximum Doppler velocity shift
Symmetry constraints for the emission angle dependence of HBT radii
Heinz, Ulrich W; Lisa, M A; Wiedemann, Urs Achim
2002-01-01
We discuss symmetry constraints on the azimuthal oscillations of two-particle correlation (Hanbury Brown--Twiss interferometry) radii for non-central collisions between equal spherical nuclei. We also propose a new method for correcting in a model-independent way the emission angle dependent correlation function for finite event plane resolution and angular binning effects.
Off-Angle Iris Correction using a Biological Model
Energy Technology Data Exchange (ETDEWEB)
Thompson, Joseph T [ORNL; Santos-Villalobos, Hector J [ORNL; Karakaya, Mahmut [ORNL; Barstow, Del R [ORNL; Bolme, David S [ORNL; Boehnen, Chris Bensing [ORNL
2013-01-01
This work implements an eye model to simulate corneal refraction effects. Using this model, ray tracing is performed to calculate transforms to remove refractive effects in off-angle iris images when reprojected to a frontal view. The correction process is used as a preprocessing step for off-angle iris images for input to a commercial matcher. With this method, a match score distribution mean improvement of 11.65% for 30 degree images, 44.94% for 40 degree images, and 146.1% improvement for 50 degree images is observed versus match score distributions with unmodi ed images.
[Correction Multiplicative Effects in Raman Spectra through Vector Angle Transformation].
Yao, Zhi-xiang; Sun, Zeng-qiang; Su, Hui; Yuan, Hong-fu
2016-02-01
obtained at different Raman integral times and have remarkable multiplicative effects. In predicting results, the correlation coefficient (r) and the root mean squared error of prediction (RMSEP) from class PLS respectively are 0.911 9 and 0.110 2, and 0.906 0 and 0.100 8 are for the preprocessing by multiplicative scatter correction (MSC). In contrast, r and RMSEP under the VAPLS, presented by this thesis, respectively are 0.998 7 and 0.015 2 and are significantly better than others. The VAPLS has eliminated the multiplicative effects of Raman spectra and improved the accuracy of Raman quantitative analysis and it owes to the preprocessing of the vector angle transformation. PMID:27209742
Range-Angle-Dependent Beamforming by Frequency Diverse Array Antenna
Wen-Qin Wang; Huaizong Shao; Jingye Cai
2012-01-01
This paper proposes a range-angle-dependent beamforming for frequency diverse array (FDA) antenna systems. Unlike conventional phased-array antenna, the FDA antenna employs a small amount of frequency increment compared to the carrier frequency across the array elements. The use of frequency increment generates an antenna pattern that is a function of range, time and angle. The range-angle-dependent beamforming allows the FDA antenna to transmit energy over a desired range or angle. This prov...
Source distribution dependent scatter correction for PVI
International Nuclear Information System (INIS)
Source distribution dependent scatter correction methods which incorporate different amounts of information about the source position and material distribution have been developed and tested. The techniques use image to projection integral transformation incorporating varying degrees of information on the distribution of scattering material, or convolution subtraction methods, with some information about the scattering material included in one of the convolution methods. To test the techniques, the authors apply them to data generated by Monte Carlo simulations which use geometric shapes or a voxelized density map to model the scattering material. Source position and material distribution have been found to have some effect on scatter correction. An image to projection method which incorporates a density map produces accurate scatter correction but is computationally expensive. Simpler methods, both image to projection and convolution, can also provide effective scatter correction
Elevation angle dependence of the SMA antenna focus position
Matsushita, S; Sakamoto, K; Hunter, T R; Patel, N A; Sridharan, T K; Wilson, R W; Matsushita, Satoki; Saito, Masao; Sakamoto, Kazushi; Hunter, Todd R.; Patel, Nimesh A.; Sridharan, Tirupati K.; Wilson, Robert W.
2006-01-01
We report the measurement results and compensation of the antenna elevation angle dependences of the Sub-millimeter Array (SMA) antenna characteristics. Without optimizing the subreflector (focus) positions as a function of the antenna elevation angle, antenna beam patterns show lopsided sidelobes, and antenna efficiencies show degradations. The sidelobe level increases and the antenna efficiencies decrease about 1% and a few %, respectively, for every 10 degrees change in the elevation angle at the measured frequency of 237 GHz. We therefore obtained the optimized subreflector positions for X (azimuth), Y (elevation), and Z (radio optics) focus axes at various elevation angles for all the eight SMA antennas. The X axis position does not depend on the elevation angle. The Y and Z axes positions depend on the elevation angles, and are well fitted with a simple function for each axis with including a gravity term (cosine and sine of elevation, respectively). In the optimized subreflector positions, the antenna ...
Lyapustin, A.; Wang, Y.; Laszlo, I.; Hilker, T.; Hall, F.; Sellers, P.; Tucker, J.; Korkin, S.
2012-01-01
This paper describes the atmospheric correction (AC) component of the Multi-Angle Implementation of Atmospheric Correction algorithm (MAIAC) which introduces a new way to compute parameters of the Ross-Thick Li-Sparse (RTLS) Bi-directional reflectance distribution function (BRDF), spectral surface albedo and bidirectional reflectance factors (BRF) from satellite measurements obtained by the Moderate Resolution Imaging Spectroradiometer (MODIS). MAIAC uses a time series and spatial analysis for cloud detection, aerosol retrievals and atmospheric correction. It implements a moving window of up to 16 days of MODIS data gridded to 1 km resolution in a selected projection. The RTLS parameters are computed directly by fitting the cloud-free MODIS top of atmosphere (TOA) reflectance data stored in the processing queue. The RTLS retrieval is applied when the land surface is stable or changes slowly. In case of rapid or large magnitude change (as for instance caused by disturbance), MAIAC follows the MODIS operational BRDF/albedo algorithm and uses a scaling approach where the BRDF shape is assumed stable but its magnitude is adjusted based on the latest single measurement. To assess the stability of the surface, MAIAC features a change detection algorithm which analyzes relative change of reflectance in the Red and NIR bands during the accumulation period. To adjust for the reflectance variability with the sun-observer geometry and allow comparison among different days (view geometries), the BRFs are normalized to the fixed view geometry using the RTLS model. An empirical analysis of MODIS data suggests that the RTLS inversion remains robust when the relative change of geometry-normalized reflectance stays below 15%. This first of two papers introduces the algorithm, a second, companion paper illustrates its potential by analyzing MODIS data over a tropical rainforest and assessing errors and uncertainties of MAIAC compared to conventional MODIS products.
Drop Size Dependence of the Contact Angle of Nanodroplets
Institute of Scientific and Technical Information of China (English)
GUO Hong-Kai; FANG Hai-Ping
2005-01-01
@@ The contact angle of nanosized non-polarized argon sessile droplets on a solid substrate is studied by using molecular dynamics simulations.It is found that the drop size dependence of the contact angle is sensitive to the interaction between the liquid molecules and solid molecules.The contact angle decreases with the decreasing drop size for larger interaction between the liquid molecules and the solid substrate, and vice versa.This observation is consistent with most of the previous theoretical and experimental results.
Energy dependence corrections to MOSFET dosimetric sensitivity.
Cheung, T; Butson, M J; Yu, P K N
2009-03-01
Metal Oxide Semiconductor Field Effect Transistors (MOSFET's) are dosimeters which are now frequently utilized in radiotherapy treatment applications. An improved MOSFET, clinical semiconductor dosimetry system (CSDS) which utilizes improved packaging for the MOSFET device has been studied for energy dependence of sensitivity to x-ray radiation measurement. Energy dependence from 50 kVp to 10 MV x-rays has been studied and found to vary by up to a factor of 3.2 with 75 kVp producing the highest sensitivity response. The detectors average life span in high sensitivity mode is energy related and ranges from approximately 100 Gy for 75 kVp x-rays to approximately 300 Gy at 6 MV x-ray energy. The MOSFET detector has also been studied for sensitivity variations with integrated dose history. It was found to become less sensitive to radiation with age and the magnitude of this effect is dependant on radiation energy with lower energies producing a larger sensitivity reduction with integrated dose. The reduction in sensitivity is however approximated reproducibly by a slightly non linear, second order polynomial function allowing corrections to be made to readings to account for this effect to provide more accurate dose assessments both in phantom and in-vivo. PMID:19400548
Angle-dependent bandgap engineering in gated graphene superlattices
García-Cervantes, H.; Gaggero-Sager, L. M.; Sotolongo-Costa, O.; Naumis, G. G.; Rodríguez-Vargas, I.
2016-03-01
Graphene Superlattices (GSs) have attracted a lot of attention due to its peculiar properties as well as its possible technological implications. Among these characteristics we can mention: the extra Dirac points in the dispersion relation and the highly anisotropic propagation of the charge carriers. However, despite the intense research that is carried out in GSs, so far there is no report about the angular dependence of the Transmission Gap (TG) in GSs. Here, we report the dependence of TG as a function of the angle of the incident Dirac electrons in a rather simple Electrostatic GS (EGS). Our results show that the angular dependence of the TG is intricate, since for moderated angles the dependence is parabolic, while for large angles an exponential dependence is registered. We also find that the TG can be modulated from meV to eV, by changing the structural parameters of the GS. These characteristics open the possibility for an angle-dependent bandgap engineering in graphene.
Cloak based on the angle dependent constitutive parameters tensors.
Gurvitz, Egor; Andronaki, Semen; Vozianova, Anna; Khodzitsky, Mikhail
2015-10-01
The transformation optics cloak was proposed for the medium with the angle dependent tensors of permittivity and permeability consisted of the right-handed and left-handed metamaterial media. The cloaking effect was numerically simulated using finite element method in the terahertz frequency range for different wave sources. The impact of cloaking medium thickness on the invisibility effect was demonstrated. PMID:26480088
Coulomb Correction to the Screening Angle of the Moliere Multiple Scattering Theory
Kuraev, E. A.; Voskresenskaya, O. O.; Tarasov, A. V.
2012-01-01
High-energy Coulomb correction to the screening angular parameter of the Moliere multiple scattering theory is found. Numerical calculations are presented in the range of nuclear charge from Z=4 to Z=82. The accuracy of the Moliere theory in determining the Coulomb correction to the screening angle is estimated.
Angle dependence of Andreev scattering at semiconductor-superconductor interfaces
DEFF Research Database (Denmark)
Mortensen, Asger; Flensberg, Karsten; Jauho, Antti-Pekka
1999-01-01
We study the angle dependence of the Andreev scattering at a semiconductor-superconductor interface, generalizing the one-dimensional theory of Blonder, Tinkham, and Klapwijk (BTK),An increase of the momentum parallel to the interface leads to suppression of the probability of Andreev reflection ...... angle of incidence above which only normal reflection exists. For two- and three-dimensional interfaces a lower excess current compared to ballistic transport with perpendicular incidence is found. Thus, the one-dimensional BTK model overestimates the barrier strength for two- and three...
Demonstration of angle-dependent Casimir force between corrugations.
Banishev, A A; Wagner, J; Emig, T; Zandi, R; Mohideen, U
2013-06-21
The normal Casimir force between a sinusoidally corrugated gold coated plate and a sphere was measured at various angles between the corrugations using an atomic force microscope. A strong dependence on the orientation angle of the corrugation is found. The measured forces were found to deviate from the proximity force approximation and are in agreement with the theory based on the gradient expansion including correlation effects of geometry and material properties. We analyze the role of temperature. The obtained results open new opportunities for control of the Casimir effect in micromechanical systems. PMID:23829717
Method for Correcting Control Surface Angle Measurements in Single Viewpoint Photogrammetry
Burner, Alpheus W. (Inventor); Barrows, Danny A. (Inventor)
2006-01-01
A method of determining a corrected control surface angle for use in single viewpoint photogrammetry to correct control surface angle measurements affected by wing bending. First and second visual targets are spaced apart &om one another on a control surface of an aircraft wing. The targets are positioned at a semispan distance along the aircraft wing. A reference target separation distance is determined using single viewpoint photogrammetry for a "wind off condition. An apparent target separation distance is then computed for "wind on." The difference between the reference and apparent target separation distances is minimized by recomputing the single viewpoint photogrammetric solution for incrementally changed values of target semispan distances. A final single viewpoint photogrammetric solution is then generated that uses the corrected semispan distance that produced the minimized difference between the reference and apparent target separation distances. The final single viewpoint photogrammetric solution set is used to determine the corrected control surface angle.
XFEL OSCILLATOR SIMULATION INCLUDING ANGLE-DEPENDENT CRYSTAL REFLECTIVITY
International Nuclear Information System (INIS)
The oscillator package within the GINGER FEL simulation code has now been extended to include angle-dependent reflectivity properties of Bragg crystals. Previously, the package was modified to include frequencydependent reflectivity in order to model x-ray FEL oscillators from start-up from shot noise through to saturation. We present a summary of the algorithms used for modeling the crystal reflectivity and radiation propagation outside the undulator, discussing various numerical issues relevant to the domain of high Fresnel number and efficient Hankel transforms. We give some sample XFEL-O simulation results obtained with the angle-dependent reflectivity model, with particular attention directed to the longitudinal and transverse coherence of the radiation output.
Crack depth profiling using guided wave angle dependent reflectivity
International Nuclear Information System (INIS)
Tomographic corrosion monitoring techniques have been developed, using two rings of sensors around the circumference of a pipe. This technique is capable of providing a detailed wall thickness map, however this might not be the only type of structural damage. Therefore this concept is expanded to detect and size cracks and small corrosion defects like root corrosion. The expanded concept uses two arrays of guided-wave transducers, collecting both reflection and transmission data. The data is processed such that the angle-dependent reflectivity is obtained without using a baseline signal of a defect-free situation. The angle-dependent reflectivity is the input of an inversion scheme that calculates a crack depth profile. From this profile, the depth and length of the crack can be determined. Preliminary experiments show encouraging results. The depth sizing accuracy is in the order of 0.5 mm
Angle-dependent vortex structure in a high anisotropy superconductor
International Nuclear Information System (INIS)
Angle-dependent muon spin rotation measurements have been made on the organic superconductor κ-(BEDT-TTF)2Cu(SCN)2. Oscillations are observed in the width of the internal field distribution, which are periodic in the perpendicular component of the applied magnetic field, Bz=B cos θ, with a uniform period over a range of angles and fields. These oscillations are superimposed on the standard cos θ scaling expected for the width in a highly anisotropic superconductor. The oscillation period is of order 2 mT and the amplitude is particularly strong at fields comparable with the period. The origin of this novel phenomenon is discussed in terms of the low field instabilities of tilted vortices in this highly anisotropic superconductor
Extended incident-angle dependence formula of sputter yield
International Nuclear Information System (INIS)
We extend a new semi-empirical formula for incident-angle dependence of normalized sputter yield that includes the contribution to sputter yield from the direct knock-out process that was not considered in the previously proposed one. Three parameters included in the new one are estimated for data calculated with ACAT code for D+ ions incident obliquely on C, Fe and W materials in incident-energy regions from several tens of eV to 10 keV. Then, the parameters are expressed with functions of incident energy. The formula with the functions derived well reproduces that using the ACAT data in the whole energy range. (author)
Angle-dependent loop shifts in antiferromagnetic nanoparticles
Mao, Zhongquan; Zhan, Xiaozhi; Chen, Xi
2016-08-01
Experimentally hysteresis loop shifts have been widely observed in antiferromagnetic (AF) nanoparticles. Here numerical investigations show that this effect is dependent on the angle between the easy axis of the AF spins and the applied magnetic field in uncompensated nanoparticles. In contrast, the loop shifts disappear in compensated nanoparticles. The results suggest that the uncompensated spins and field directions are essential ingredients to generate loop shifts in AF nanoparticle systems. The present study hints at a possible way to optimize the magnetic performance of AF nanostructures.
Coulomb Correction to the Screening Angle of the Moliere Multiple Scattering Theory
Kuraev, E A; Tarasov, A V
2012-01-01
Coulomb correction to the screening angular parameter of the Moliere multiple scattering theory is found. Numerical calculations are presented in the range of nuclear charge from Z=4 to Z=82. Comparison with the approximate Moliere result for the screening angle reveals up to 30% deviation from it for sufficiently heavy elements of the target material.
Coulomb correction to the screening angle of the Moliere multiple scattering theory
International Nuclear Information System (INIS)
Coulomb correction to the screening angular parameter of the Moliere multiple scattering theory is found. Numerical calculations are presented in the range of nuclear charge 4 ≤ Z ≤ 82. Comparison with the Moliere result for the screening angle reveals up to 30% deviation from it for sufficiently heavy elements of the target material
The height of the osteotomy and the correction of the kyphotic angle in thoracolumbar kyphosis
Institute of Scientific and Technical Information of China (English)
HAO Chou-kuan; LI Wei-shi; CHEN Zhong-qiang
2008-01-01
Background This study investigated the relationship between the height of osteotomy and the correction of the kyphotic angle during posterior closing wedge osteotmy with instrumentation and the spinal osteotomy with cage inserting into the intervertebral gap and closing posteriorly by a single posterior approach in thoracolumbar kyphosis, and using this relationship as the basis of the preoperative design.Methods From April 1996 to June 2007, 30 thoracolumbar kyphosis patients with complete medical records and clear X-ray photograms have undergone operation. Of these 30 cases, 16 cases underwent posterior closing wedge osteotmywith instrumentation while the height of the osteotomy and the correction of the angle have been measured; 14 casesunderwent spinal osteotomy with cage inserting into the intervertebral gap and closing posteriorly by a single posteriorapproach while the height of the osteotomy, the height and the place of the cage and the correction of the angle were also measured. A simple geometrical model was simulated to calculate the relationship between the height of the osteotomy and the correction of the angle and these results are finally compared with the data coming from the actual measuring by the Wilcoxon statistic method.Results The distribution of data from the 16 cases by posterior closing wedge osteotomy with instrumentation was as such: 9 male and 7 female, the mean age was 49.2 years (range 38-70), the kyphosis improved from an average of 30° (range 15°-45°) preoperatively to 4° (range -26°-30°) postoperatively, the kyphosis was corrected on average 2.5° per 1 mm in the height of the osteotomy. The results from the simple geometrical model were that the mean of the correction of the angle per 1 mm was 2.2°. As a result, there was no significant difference (P >0.05) when comparing the measurement collected with the result simulated from the geometric model. The distribution of data from the 14 cases by spinal osteotomy with cage
THE EFFECTS OF LASER REFLECTION ANGLE ON RADIOMETRIC CORRECTION OF THE AIRBORNE LIDAR INTENSITY DATA
Directory of Open Access Journals (Sweden)
A. Shaker
2012-09-01
Full Text Available Radiometric correction (RC of the airborne Light Detection And Ranging (LiDAR intensity data has been studied in the last few years. The physical model of the RC relies on the use of the laser range equation to convert the intensity values into the spectral reflectance of the reflected objects. A number of recent studies investigated the effects of the LiDAR system parameters (i.e. range, incidence angle, beam divergence, aperture size, automatic gain control, etc. on the results of the RC process. Nevertheless, the condition of the object surface (slope and aspect plays a crucial role in modelling the recorded intensity data. The variation of the object surface slope and aspect affects the direction as well as the magnitude of the reflected laser pulse which makes significant influence on the bidirectional reflectance distribution function. In this paper, the effects of the angle of reflection, which is the angle between the surface normal and the incidence laser pulse, on the RC results of the airborne LiDAR intensity data is investigated. A practical approach is proposed to compute the angle of reflection using the digital surface model (DSM derived from the LiDAR data. Then, a comparison between the results of the intensity data after RC using the scan angle and RC using the angle of reflection is carried out. The comparison is done by converting the intensity data into equivalent image data and evaluating the classification results of the intensity image data. Preliminary findings show that: 1 the variance-to-mean ratio of the land cover features are significantly reduced while using the angle of reflection in the RC process; 2 4% of accuracy improvement can be achieved using the intensity data corrected with the scan angle. The accuracy improvement increases to 8% when using the intensity data corrected with the angle of reflection. The research work practically justifies the use of the reflection angle in the RC process of airborne Li
Sereno, M; Debiossac, M; Kalashnyk, N; Roncin, P
2016-01-01
A procedure to measure the residual tilt angle $\\tau$ between a flat surface and the azimuthal rotation axis of the sample holder is described. When the incidence angle $\\theta$ and readout of the azimuthal angle $\\phi$ are controlled by motors, an active compensation mechanism can be implemented to reduce the effect of the tilt angle during azimuthal motion. After this correction, the effective angle of incidence is kept fixed, and only the small residual oscillation of the scattering plane remains.
Directory of Open Access Journals (Sweden)
Yu Tong
2016-02-01
Full Text Available Photoacoustic Doppler (PAD power spectra showing an evident Doppler shift represent the major characteristics of the continuous wave-excited or burst wave-excited versions of PAD flow measurements. In this paper, the flow angle dependences of the PAD power spectra are investigated using an experiment setup that was established based on intensity-modulated continuous wave laser excitation. The setup has an overall configuration that is similar to a previously reported configuration, but is more sophisticated in that it accurately aligns the laser illumination with the ultrasound detection process, and in that it picks up the correct sample position. In the analysis of the power spectra data, we find that the background power spectra can be extracted by combining the output signals from the two channels of the lock-in amplifier, which is very useful for identification of the PAD power spectra. The power spectra are presented and analyzed in opposite flow directions, at different flow speeds, and at different flow angles. The power spectra at a 90° flow angle show the unique properties of symmetrical shapes due to PAD broadening. For the other flow angles, the smoothed power spectra clearly show a flow angle cosine relationship.
Wide angle Compton scattering on the proton: study of power suppressed corrections
Kivel, N
2015-01-01
We study the wide angle Compton scattering process on a proton within the soft collinear factorization (SCET) framework. The main purpose of this work is to estimate the effect due to certain power suppressed corrections. We consider all possible kinematical power corrections and also include the subleading amplitudes describing the scattering with nucleon helicity flip. Under certain assumptions we present a leading-order factorization formula for these amplitudes which includes the hard- and soft-spectator contributions. We apply the formalism and perform a phenomenological analysis of the cross section and asymmetries in the wide angle Compton scattering on a proton. We assume that in the relevant kinematical region where $-t,-u>2.5$~GeV$^{2}$ the dominant contribution is provided by the soft-spectator mechanism. The hard coefficient functions of the corresponding SCET operators are taken in the leading-order approximation. The analysis of existing cross section data shows that the contribution of the heli...
Comparison of Alignment Correction Angles Between Fixed-Bearing and Mobile-Bearing UKA.
Inoue, Atsuo; Arai, Yuji; Nakagawa, Shuji; Inoue, Hiroaki; Yamazoe, Shoichi; Kubo, Toshikazu
2016-01-01
Good outcomes have been reported with both fixed-bearing and mobile-bearing unicompartmental knee arthroplasty (UKA). However, overcorrected alignment could induce the progression of arthritis on the non-arthroplasty side. Changes of limb alignment after UKA with both types of bearings (fixed bearing: 24 knees, mobile bearing: 28 knees) were investigated. The mean difference between the preoperative standing femoral-tibial angle (FTA) and postoperative standing FTA was significantly larger in mobile bearing UKA group. In fixed-bearing UKA, there must be some laxity in MCL tension so that a 2-mm tension gauge can be inserted. In mobile-bearing UKA, appropriate MCL tension is needed to prevent bearing dislocation. This difference in MCL tension may have caused the difference in the correction angle between the groups. PMID:26264178
Finite solid angle correction factors and efficiencies for cadmium telluride detectors
International Nuclear Information System (INIS)
Finite solid angle correction factors and absolute detection efficiencies of the CdTe detectors of right circular cylindrical geometry for point sources placed on the axis of the detector, has been calculated for γ-ray energies from 100keV to 10MeV, taking into account various source to detector distances, ranging from 1 to 10cm. CdTe detectors of several area between 0.12 and 2.5cm2 of various thickness were considered
Electroweak two-loop corrections to the effective weak mixing angle
International Nuclear Information System (INIS)
Recently exact results for the complete electroweak two-loop contributions to the effective weak mixing angle were published. This paper illustrates the techniques used for this computation, in particular the methods for evaluating the loop diagrams and the proper definition of Z-pole observables at next-to-next -to-leading order. Numerical results are presented in terms of simple parametrization formulae and compared in detail with a previous result of an expansion up to next-to-leading order in the top-quark mass. Finally, an estimate of the remaining theoretical uncertainties from unknown higher-order corrections is given. (Orig.)
Improving Planck calibration by including frequency-dependent relativistic corrections
Quartin, Miguel
2015-01-01
The Planck satellite detectors are calibrated in the 2015 release using the "orbital dipole", which is the time-dependent dipole generated by the Doppler effect due to the motion of the satellite around the Sun. Such an effect has also relativistic time-dependent corrections of relative magnitude 10^(-3), due to coupling with the "solar dipole" (the motion of the Sun compared to the CMB rest frame), which are included in the data calibration by the Planck collaboration. We point out that such corrections are subject to a frequency-dependent multiplicative factor. This factor differs from unity especially at the highest frequencies, relevant for the HFI instrument. Since currently Planck calibration errors are dominated by systematics, to the point that polarization data is currently unreliable at large scales, such a correction can in principle be highly relevant for future data releases.
Opel, S; Konan, S; Sorene, E
2014-05-01
Post-traumatic distal radius deformity may cause severe morbidity, and corrective osteotomy is often necessary to realign the functional axis of the wrist to correct symptomatic malunion. The aim of this retrospective study was to review the short-term results of a single surgeon’s series of distalradius corrective osteotomies following fracture malunion using a fixed-angle volar locking plate for 20 patients(16 women) of an average age of 57 (range 19–83) years [corrected].At short-term follow up (average 14 months, range 12-15 months), no complications were noted and radiological union was confirmed in all cases at an average of 3 months. The average post-operative Disability of the Arm, Shoulder and Hand score was 13.48 (range 0-48.33) and an objective improvement was noted in movements at the wrist joint. A statistically significant improvement was achieved in ulnar variance, radial inclination, dorsal tilt, and supination. PMID:24051477
Selection Effects on the Observed Redshift Dependence of GRB Jet Opening Angles
Lu, Rui-Jing; Qin, Shu-Fu; Liang, En-Wei
2011-01-01
Apparent redshift dependence of the jet opening angles ($\\theta_{\\rm j}$) of gamma-ray bursts (GRBs) is observed from current GRB sample. We investigate whether this dependence can be explained with instrumental selection effects and observational biases by a bootstrapping method. Assuming that (1) the GRB rate follows the star formation history and the cosmic metallicity history and (2) the intrinsic distributions of the jet-corrected luminosity ($L_{\\rm \\gamma}$) and $\\theta_{\\rm j}$ are a Gaussian or a power-law function, we generate a mock {\\em Swift}/BAT sample by considering various instrumental selection effects, including the flux threshold and the trigger probability of BAT, the probabilities of a GRB jet pointing to the instrument solid angle and the probability of redshift measurement. Our results well reproduce the observed $\\theta_{\\rm j}-z$ dependence. We find that in case of $L_{\\gamma}\\propto \\theta_{\\rm j}^2$ good consistency between the mock and observed samples can be obtained, indicating t...
Wide angle Compton scattering on the proton: study of power suppressed corrections
Energy Technology Data Exchange (ETDEWEB)
Kivel, N.; Vanderhaeghen, M. [Johannes Gutenberg-Universitaet, Helmholtz Institut Mainz, Mainz (Germany); Johannes Gutenberg-Universitaet, Institut fuer Kernphysik, Mainz (Germany)
2015-10-15
We study the wide angle Compton scattering process on a proton within the soft-collinear factorization (SCET) framework. The main purpose of this work is to estimate the effect due to certain power suppressed corrections. We consider all possible kinematical power corrections and also include the subleading amplitudes describing the scattering with nucleon helicity flip. Under certain assumptions we present a leading-order factorization formula for these amplitudes which includes the hard- and soft-spectator contributions. We apply the formalism and perform a phenomenological analysis of the cross section and asymmetries in the wide angle Compton scattering on a proton. We assume that in the relevant kinematical region where -t, -u > 2.5 GeV{sup 2} the dominant contribution is provided by the soft-spectator mechanism. The hard coefficient functions of the corresponding SCET operators are taken in the leading-order approximation. The analysis of existing cross section data shows that the contribution of the helicity-flip amplitudes to this observable is quite small and comparable with other expected theoretical uncertainties. We also show predictions for double polarization observables for which experimental information exists. (orig.)
Wide angle Compton scattering on the proton: study of power suppressed corrections
Kivel, N.; Vanderhaeghen, M.
2015-10-01
We study the wide angle Compton scattering process on a proton within the soft-collinear factorization (SCET) framework. The main purpose of this work is to estimate the effect due to certain power suppressed corrections. We consider all possible kinematical power corrections and also include the subleading amplitudes describing the scattering with nucleon helicity flip. Under certain assumptions we present a leading-order factorization formula for these amplitudes which includes the hard- and soft-spectator contributions. We apply the formalism and perform a phenomenological analysis of the cross section and asymmetries in the wide angle Compton scattering on a proton. We assume that in the relevant kinematical region where -t,-u>2.5 GeV2 the dominant contribution is provided by the soft-spectator mechanism. The hard coefficient functions of the corresponding SCET operators are taken in the leading-order approximation. The analysis of existing cross section data shows that the contribution of the helicity-flip amplitudes to this observable is quite small and comparable with other expected theoretical uncertainties. We also show predictions for double polarization observables for which experimental information exists.
Bias-corrected estimation of stable tail dependence function
DEFF Research Database (Denmark)
Beirlant, Jan; Escobar-Bach, Mikael; Goegebeur, Yuri;
2016-01-01
We consider the estimation of the stable tail dependence function. We propose a bias-corrected estimator and we establish its asymptotic behaviour under suitable assumptions. The finite sample performance of the proposed estimator is evaluated by means of an extensive simulation study where a...
An efficient decomposition technique to solve angle-dependent Hanle scattering problems
Supriya, H D; Nagendra, K N; Ravindra, B; Anusha, L S; 10.1016/j.jqsrt.2012.12.016
2013-01-01
Hanle scattering is an important diagnostic tool to study weak solar magnetic fields. Partial frequency redistribution (PRD) is necessary to interpret the linear polarization observed in strong resonance lines. Usually angle-averaged PRD functions are used to analyze linear polarization. However it is established that angle-dependent PRD functions are often necessary to interpret polarization profiles formed in the presence of weak magnetic fields. Our aim is to present an efficient decomposition technique, and the numerical method to solve the concerned angle-dependent line transfer problem. Together with the standard Stokes decomposition technique we employ Fourier expansion over the outgoing azimuth angle to express in a more convenient form, the angle-dependent PRD function for the Hanle effect. It allows the use of angle-dependent frequency domains of Bommier to solve the Hanle transfer problem. Such an approach is self-consistent and accurate compared to a recent approach where angle-averaged frequency ...
A coupled elastoplastic-damage constitutive model with Lode angle dependent failure criterion
Erice Echávarri, Borja; Galvez Diaz-Rubio, Francisco
2014-01-01
A coupled elastoplastic-damage constitutive model with Lode angle dependent failure criterion for high strain and ballistic applications is presented. A Lode angle dependent function is added to the equivalent plastic strain to failure definition of the Johnson–Cook failure criterion. The weakening in the elastic law and in the Johnson–Cook-like constitutive relation implicitly introduces the Lode angle dependency in the elastoplastic behaviour. The material model is calibrated for precipitat...
Li, An; Wu, Yi-si; Chen, Chi; Zheng, Zhen-rong
2015-09-01
The wide angle lens, like fish eye lens, suffers great optical distortion that causes severe deformation of the real world. A method to correct the strong distortion was presented in this work. Due to the nonlinear distribution of the distortion, linear algorithms are generally not under consideration to establish the math model of distorted-to-ideal images. However, this method employed the calibration pattern that comprised of regular array of dots to divides the full field of view (FOV) to subsections, each subsection is a small FOV, the mapping parameters between the distorted image and ideal image in each small FOV can be calculated by employing the very simple linear polynomial. Thus, applying the determined parameters to their corresponding sub-FOVs, respectively, all the ideal pixel coordinates of the distorted image can be obtained. The method employed linear polynomial characterizes the geometric deformation between the distorted and ideal images directly. Therefore, it contains both of radial distortion and tangential distortion and there is no need of concerning any intrinsic or extrinsic parameters of the optical systems. So, this algorithm reliefs the computational work that employed by conventional radial models and other mathematical models. Experiments performed on off-axis optical systems which exist complicated distortion, such as the head mounted displays (HMDs), had already yielded accurate correcting results. Likewise, in this paper, the experiments refer to the fish-eye lens also verify the effectiveness and flexibility of this method, as well, high correcting accuracy is achieved.
Apex-angle-dependent resonances in triangular split ring resonators
Burnett, Max A
2016-01-01
Along with other frequency selective structures [1] (circles and squares), triangular split-ring resonators (TSRRs) only allow frequencies near the center resonant frequency to propagate. Further, TSRRs are attractive due to their small surface area [2], comparatively, and large quality factors (Q) factors as previously investigated by Gay-Balmaz, et al. [3]. In this work we examine the effects of varying the apex angle on the resonant frequency, the Q factor, and the phase shift imparted by the TSRR element within the GHz frequency regime.
Sissay, Adonay; Abanador, Paul; Mauger, François; Gaarde, Mette; Schafer, Kenneth J; Lopata, Kenneth
2016-09-01
Strong-field ionization and the resulting electronic dynamics are important for a range of processes such as high harmonic generation, photodamage, charge resonance enhanced ionization, and ionization-triggered charge migration. Modeling ionization dynamics in molecular systems from first-principles can be challenging due to the large spatial extent of the wavefunction which stresses the accuracy of basis sets, and the intense fields which require non-perturbative time-dependent electronic structure methods. In this paper, we develop a time-dependent density functional theory approach which uses a Gaussian-type orbital (GTO) basis set to capture strong-field ionization rates and dynamics in atoms and small molecules. This involves propagating the electronic density matrix in time with a time-dependent laser potential and a spatial non-Hermitian complex absorbing potential which is projected onto an atom-centered basis set to remove ionized charge from the simulation. For the density functional theory (DFT) functional we use a tuned range-separated functional LC-PBE*, which has the correct asymptotic 1/r form of the potential and a reduced delocalization error compared to traditional DFT functionals. Ionization rates are computed for hydrogen, molecular nitrogen, and iodoacetylene under various field frequencies, intensities, and polarizations (angle-dependent ionization), and the results are shown to quantitatively agree with time-dependent Schrödinger equation and strong-field approximation calculations. This tuned DFT with GTO method opens the door to predictive all-electron time-dependent density functional theory simulations of ionization and ionization-triggered dynamics in molecular systems using tuned range-separated hybrid functionals. PMID:27608987
Angle-dependent bandgap engineering in gated graphene superlattices
H. García-Cervantes; Gaggero-Sager, L. M.; Sotolongo-Costa, O.; Naumis, G. G.; Rodríguez-Vargas, I.
2016-01-01
Graphene Superlattices (GSs) have attracted a lot of attention due to its peculiar properties as well as its possible technological implications. Among these characteristics we can mention: the extra Dirac points in the dispersion relation and the highly anisotropic propagation of the charge carriers. However, despite the intense research that is carried out in GSs, so far there is no report about the angular dependence of the Transmission Gap (TG) in GSs. Here, we report the dependence of TG...
Saito, Seiki; Nakamura, Hiroaki
2009-01-01
Incident angle dependence of reactions between graphene and hydrogen atoms are obtained qualitatively by classical molecular dynamics simulation under the NVE condition with modified Brenner reactive empirical bond order (REBO) potential. Chemical reaction depends on two parameters, i.e., polar angle $\\theta$ and azimuthal angle $\\phi$ of the incident hydrogen. From the simulation results, it is found that the reaction rates strongly depend on polar angle $\\theta$. Reflection rate becomes larger with increasing $\\theta$, and the $\\theta$ dependence of adsorption rate is also found. The $\\theta$ dependence is caused by three dimensional structure of the small potential barrier which covers adsorption sites. $\\phi$ dependence of penetration rate is also found for large $\\theta$.
International Nuclear Information System (INIS)
In pole figure measurement by X-ray diffraction, the intensity must be corrected for geometric factors entering into the intensity. For the grazing (often, also called glancing) angle diffraction mode, the irradiated area changes with the grazing angle. A theoretical analysis of this effect was made and compared with measured data from a texture-free silver sample. An intensity correction factor is given as the ratio of the detector slit width and the width of the irradiated sample area as seen from the detector. As an application, the texture of thin copper film was studied
THE BEHAVIOR OF THE PITCH ANGLE OF SPIRAL ARMS DEPENDING ON OPTICAL WAVELENGTH
International Nuclear Information System (INIS)
Based on integral field spectroscopy data from the CALIFA survey, we investigate the possible dependence of spiral arm pitch angle with optical wavelength. For three of the five studied objects, the pitch angle gradually increases at longer wavelengths. This is not the case for two objects where the pitch angle remains constant. This result is confirmed by the analysis of SDSS data. We discuss the possible physical mechanisms to explain this phenomenon, as well as the implications of the results
International Nuclear Information System (INIS)
Experimental investigations is carried out for the orientational dependence of the mean square of the multiple scattering angle at small incidence angles of 4.5 GeV electrons relative to crystallographic (110) planes of diamond. A theoretical discussion of the experiment is reported. 4 refs.; 2 figs
Parametric Study of the Device Angle Dependency of a Single Vortex Generator on a Flat Plate
DEFF Research Database (Denmark)
Fernandez, U.; Réthoré, Pierre-Elouan; Sørensen, Niels N.; Velte, Clara Marika; Zahle, Frederik; Egusquiza, E.
A detailed study of the device angle dependency of a single vortex generator (VG) is presented in this paper. A single Vortex Generator on a test section wall case, with four different positions of the device angle to the incoming flow, has been designed and solved by computational methods. The...
Finite-difference solution of the space-angle-lethargy-dependent slowing-down transport equation
International Nuclear Information System (INIS)
A procedure has been developed for solving the slowing-down transport equation for a cylindrically symmetric reactor system. The anisotropy of the resonance neutron flux is treated by the spherical harmonics formalism, which reduces the space-angle-Iethargy-dependent transport equation to a matrix integro-differential equation in space and lethargy. Replacing further the lethargy transfer integral by a finite-difference form, a set of matrix ordinary differential equations is obtained, with lethargy-and space dependent coefficients. If the lethargy pivotal points are chosen dense enough so that the difference correction term can be ignored, this set assumes a lower block triangular form and can be solved directly by forward block substitution. As in each step of the finite-difference procedure a boundary value problem has to be solved for a non-homogeneous system of ordinary differential equations with space-dependent coefficients, application of any standard numerical procedure, for example, the finite-difference method or the method of adjoint equations, is too cumbersome and would make the whole procedure practically inapplicable. A simple and efficient approximation is proposed here, allowing analytical solution for the space dependence of the spherical-harmonics flux moments, and hence the derivation of the recurrence relations between the flux moments at successive lethargy pivotal points. According to the procedure indicated above a computer code has been developed for the CDC -3600 computer, which uses the KEDAK nuclear data file. The space and lethargy distribution of the resonance neutrons can be computed in such a detailed fashion as the neutron cross-sections are known for the reactor materials considered. The computing time is relatively short so that the code can be efficiently used, either autonomously, or as part of some complex modular scheme. Typical results will be presented and discussed in order to prove and illustrate the applicability of the
SU-E-T-195: Gantry Angle Dependency of MLC Leaf Position Error
International Nuclear Information System (INIS)
Purpose: The aim of this study was to investigate the gantry angle dependency of the multileaf collimator (MLC) leaf position error. Methods: An automatic MLC quality assurance system (AutoMLCQA) was developed to evaluate the gantry angle dependency of the MLC leaf position error using an electronic portal imaging device (EPID). To eliminate the EPID position error due to gantry rotation, we designed a reference maker (RM) that could be inserted into the wedge mount. After setting up the EPID, a reference image was taken of the RM using an open field. Next, an EPID-based picket-fence test (PFT) was performed without the RM. These procedures were repeated at every 45° intervals of the gantry angle. A total of eight reference images and PFT image sets were analyzed using in-house software. The average MLC leaf position error was calculated at five pickets (-10, -5, 0, 5, and 10 cm) in accordance with general PFT guidelines using in-house software. This test was carried out for four linear accelerators. Results: The average MLC leaf position errors were within the set criterion of <1 mm (actual errors ranged from -0.7 to 0.8 mm) for all gantry angles, but significant gantry angle dependency was observed in all machines. The error was smaller at a gantry angle of 0° but increased toward the positive direction with gantry angle increments in the clockwise direction. The error reached a maximum value at a gantry angle of 90° and then gradually decreased until 180°. In the counter-clockwise rotation of the gantry, the same pattern of error was observed but the error increased in the negative direction. Conclusion: The AutoMLCQA system was useful to evaluate the MLC leaf position error for various gantry angles without the EPID position error. The Gantry angle dependency should be considered during MLC leaf position error analysis
SU-E-T-195: Gantry Angle Dependency of MLC Leaf Position Error
Energy Technology Data Exchange (ETDEWEB)
Ju, S; Hong, C; Kim, M; Chung, K; Kim, J; Han, Y; Ahn, S; Chung, S; Shin, E; Shin, J; Kim, H; Kim, D; Choi, D [Department of Radiation Oncology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)
2014-06-01
Purpose: The aim of this study was to investigate the gantry angle dependency of the multileaf collimator (MLC) leaf position error. Methods: An automatic MLC quality assurance system (AutoMLCQA) was developed to evaluate the gantry angle dependency of the MLC leaf position error using an electronic portal imaging device (EPID). To eliminate the EPID position error due to gantry rotation, we designed a reference maker (RM) that could be inserted into the wedge mount. After setting up the EPID, a reference image was taken of the RM using an open field. Next, an EPID-based picket-fence test (PFT) was performed without the RM. These procedures were repeated at every 45° intervals of the gantry angle. A total of eight reference images and PFT image sets were analyzed using in-house software. The average MLC leaf position error was calculated at five pickets (-10, -5, 0, 5, and 10 cm) in accordance with general PFT guidelines using in-house software. This test was carried out for four linear accelerators. Results: The average MLC leaf position errors were within the set criterion of <1 mm (actual errors ranged from -0.7 to 0.8 mm) for all gantry angles, but significant gantry angle dependency was observed in all machines. The error was smaller at a gantry angle of 0° but increased toward the positive direction with gantry angle increments in the clockwise direction. The error reached a maximum value at a gantry angle of 90° and then gradually decreased until 180°. In the counter-clockwise rotation of the gantry, the same pattern of error was observed but the error increased in the negative direction. Conclusion: The AutoMLCQA system was useful to evaluate the MLC leaf position error for various gantry angles without the EPID position error. The Gantry angle dependency should be considered during MLC leaf position error analysis.
Yun, Byung Min
2016-01-01
There are many women who want larger and brighter eyes that will give a favorable impression. Surgical methods that make the eye larger and brighter include double eyelidplasty, epicanthoplasty, as well as lateral canthoplasty. Double eyelidplasty produces changes in the vertical dimension of the eyes, whereas epicanthoplasty and lateral canthoplasty create changes in the horizontal dimension of the eyes. Epicanthoplasty, a surgical procedure which enlarges the eye horizontally, is performed at the inner corner of the eye, whereas lateral canthoplasty enlarges the outer edge of the eye. In particular, if the slant of the palpebral fissure is raised and the horizontal dimension of the palpebral fissure is short, adjusting the slant of the palpebral fissure through lateral canthoplasty can achieve an enlargement of eye width and smoother features. Depending on the patient's condition, even better results can be achieved if this procedure is performed in conjunction with other procedures, such as double eyelidplasty, epicanthoplasty, eye roll formation surgery, fat graft, and facial bone contouring surgery. In this paper, the authors will introduce in detail their surgical method for a cosmetic lateral canthoplasty that lengthens the lateral canthal angle and corrects the outer tail of the eyes, in order to ease the unfavorable impression. PMID:27462564
Chae, Soo Wook; Yun, Byung Min
2016-07-01
There are many women who want larger and brighter eyes that will give a favorable impression. Surgical methods that make the eye larger and brighter include double eyelidplasty, epicanthoplasty, as well as lateral canthoplasty. Double eyelidplasty produces changes in the vertical dimension of the eyes, whereas epicanthoplasty and lateral canthoplasty create changes in the horizontal dimension of the eyes. Epicanthoplasty, a surgical procedure which enlarges the eye horizontally, is performed at the inner corner of the eye, whereas lateral canthoplasty enlarges the outer edge of the eye. In particular, if the slant of the palpebral fissure is raised and the horizontal dimension of the palpebral fissure is short, adjusting the slant of the palpebral fissure through lateral canthoplasty can achieve an enlargement of eye width and smoother features. Depending on the patient's condition, even better results can be achieved if this procedure is performed in conjunction with other procedures, such as double eyelidplasty, epicanthoplasty, eye roll formation surgery, fat graft, and facial bone contouring surgery. In this paper, the authors will introduce in detail their surgical method for a cosmetic lateral canthoplasty that lengthens the lateral canthal angle and corrects the outer tail of the eyes, in order to ease the unfavorable impression. PMID:27462564
Influence of scattering phenomena on the solar zenith angle dependence of in-water irradiance levels
International Nuclear Information System (INIS)
A Monte Carlo analysis is utilized to determine the influence of the inherent properties of a water mass on the solar zenith angle dependence of subsurface irradiance levels. It is shown that the proportion of scattering interactions (as represented by the scattering albedo ω) has a greater influence on this dependence that does the backscattering probability B. Several representations of direct and/or diffuse incident radiation are considered, and their effects on the solar zenith angle dependence are evaluated. Irradiance level data collected in Lake Erie are compared to the predictions of the Monte Carlo analysis
Dynamic switching characteristic dependence on sidewall angle for phase change memory
Long, X. M.; Miao, X. S.; Sun, J. J.; Cheng, X. M.; Tong, H.; Li, Y.; Yang, D. H.; Huang, J. D.; Liu, C.
2012-01-01
In this paper, the volume-minimized model of phase change memory (PCM) cell with Ge 2Sb 2Te 5 (GST) material has been established to study the dynamic switching (set-to-reset) characteristic dependence on the sidewall angle. Joule heating volume, threshold current, dynamic resistance and phase transition rate of PCM cells by current pulse are all calculated. The results show that the threshold current increases with decreasing the sidewall angle and is significantly impacted by the feature size and aspect ratio. The PCM cell of 90° sidewall angle exhibits the smallest Joule heating volume, the highest RESET resistance and the fastest phase transition property.
T1rho mapping of entire femoral cartilage using depth- and angle-dependent analysis
Nozaki, Taiki; Kaneko, Yasuhito; Yu, Hon J.; Kaneshiro, Kayleigh; Schwarzkopf, Ran; Hara, Takeshi; Yoshioka, Hiroshi
2015-01-01
Objectives To create and evaluate normalized T1rho profiles of the entire femoral cartilage in healthy subjects with three-dimensional (3D) angle- and depth-dependent analysis. Methods T1rho images of the knee from 20 healthy volunteers were acquired on a 3.0-T unit. Cartilage segmentation of the entire femur was performed slice-by-slice by a board-certified radiologist. The T1rho depth/angle-dependent profile was investigated by partitioning cartilage into superficial and deep layers, and an...
A mechanism for the dependence of sunspot group tilt angles on cycle strength
Işık, Emre
2015-01-01
The average tilt angle of sunspot groups emerging throughout the solar cycle determines the net magnetic flux crossing the equator, which is correlated with the strength of the subsequent cycle. I suggest that a deep-seated, non-local process can account for the observed cycle-dependent changes in the average tilt angle. Motivated by helioseismic observations indicating cycle-scale variations in the sound speed near the base of the convection zone, I determined the effect of a thermally perturbed overshoot region on the stability of flux tubes and on the tilt angles of emerging flux loops. I found that 5-20 K of cooling is sufficient for emerging flux loops to reproduce the reported amplitude of cycle-averaged tilt angle variations, suggesting that it is a plausible effect responsible for the nonlinearity of the solar activity cycle.
International Nuclear Information System (INIS)
Simultaneous and continuous muon measurements in two opposite azimuthal directions under equal zenith angles demonstrated the importance of this method for cosmic ray diurnal variation investigations. Lately these measurements were extended by means of improved telescopes. The obtained cosmic ray diurnal variations were presented as intensity differential curves. Theoretical investigations connected the properties of these curves with some interplanetary spece parameters. The harmonics of these curves were interpreted physically. Some order difference curves were introduced. In earlier works some dependences between the parameters characterizing the first and the second harmonics of the differential intensity curves and the geomagnetic activity were found. Then all measurements were carried out under only one zenith angle. The results of investigations of similar dependences using data of simultaneous measurements under three different zenith angles are presented
Aspect angle dependence of backscatter intensity of 1-m auroral plasma waves
International Nuclear Information System (INIS)
The backscatter intensities of primary and secondary 1-m unstable plasma waves in the auroral E region have been measured as a function of magnetic aspect angle (α) for electric field values between 25 and 30 mV/m. The variation of the absorption A, measured in decibels, is of the form A = -IaCo cos2 α/(1 + Co cos2 α). The best fits to the observed attenuation yield parameter values of (Ia, Co) = (49.6, 530) and (48.8, 900) for primary and secondary waves, respectively. The backscatter intensity from primary waves has the same aspect angle dependence as the mean Doppler velocity aspect angle-dependence observed in previous auroral radar data sets (Nielsen, 1986). The observations suggest that the radar backscatter cross section of the primary waves maximizes a few kilometers higher in altitude than that of the secondary waves
Theoretical interpretation of angle- and polarization-dependent laser light absorption measurements
International Nuclear Information System (INIS)
It is shown that recently published observations of angle- and polarization-dependent absorption of intense laser light are consistent with computer simulations of resonance absorption in a steepened plasma profile, with the additional assumption of a modestly rippled critical surface. About 10% absorption seems to be due to mechanisms not addressed in the simulations
THE VIRIAL OF ANGLE-DEPENDENT POTENTIALS IN MOLECULAR-DYNAMICS SIMULATIONS
BEKKER, H; AHLSTROM, P
1994-01-01
It is proved that the scalar virial of potentials that only depend on angles is zero. This is proved for nonperiodic boundary conditions as well as periodic boundary condition (PBC) systems. This theory is tested on an molecular dynamics simulation of butane with PBC.
Campbell, Kaleb; Madkhaly, Samaya; de Medeiros, Dillon; Bali, Samir; Macklin Quantum Information Sciences Collaboration
2016-05-01
Progress toward undergraduate oriented experiments on image storage in room-temperature atomic vapor using Electromagnetically Induced Transparency is described. Using a scanning longitudinal magnetic field technique we diagnose and suppress stray magnetic fields and polarization impurity. We consider the pump-probe angular dependence of the EIT signal but at much smaller angles of less than a milliradian.
On the Origin of the Trigger-Angle Dependence of the Ridge Structure
Hama, Yogiro; Grassi, Frederique; Qian, Wei-Liang
2012-01-01
The origin of the trigger-angle dependence of the ridge structure in two-hadron long-range correlations, as observed at RHIC, is discussed as due to an interplay between the elliptic flow caused by the initial state global geometry and flow produced by fluctuations.
Angle dependence of signal intensity of a bovine tendon at spin echo sequence
International Nuclear Information System (INIS)
It has been reported that the signal intensity of dense collagen fibers markedly increases in some tissues on MRI, when collagen fibers are oriented at about 55deg against the static magnetic field. This angle is sometimes called the magic angle. The magic angle phenomenon is caused by magnetic dipolar-dipolar interaction between water protons. As this phenomenon has been reported to be related to the T2 relaxation rate only, the signal intensity may be influenced by the T2 relaxation rate at the spin echo (SE) sequence if other parameters are fixed. Information regarding the increasing ratio of signal intensity depending on the angle may be clinically important. A bovine tendon was rotated horizontally in a static magnetic field and images were obtained with SE or fast spin echo (FSE) sequences as follows: (a) SE (TR/TE=2000/15, 30, 45, 60), (b) SE (TR/TE=300, 500, 700/14), (c) FSE (TR/TE=3000/15, 105 eff., echo train length=14). By comparing the theoretical curves and data, it was confirmed that the signal intensity was related to the second power of the local magnetic field strength. The increasing ratio of signal intensity of the bovine tendon at 55deg (magic angle) compared with 0deg was about 3 times (TE=30). The most influential TE was about 20-40 msec. The increasing ratio of signal intensity did not depend on TR change or the FSE technique. (author)
Chen, Cong; Zhang, Ning; Li, Weizhong; Song, Yongchen
2015-12-15
Functional groups on silica surfaces under CO2 sequestration conditions are complex due to reactions among supercritical CO2, brine and silica. Molecular dynamics simulations have been performed to investigate the effects of hydroxyl functional groups on wettability. It has been found that wettability shows a strong dependence on functional groups on silica surfaces: silanol number density, space distribution, and deprotonation/protonation degree. For neutral silica surfaces with crystalline structure (Q(3), Q(3)/Q(4), Q(4)), as silanol number density decreases, contact angle increases from 33.5° to 146.7° at 10.5 MPa and 318 K. When Q(3) surface changes to an amorphous structure, water contact angle increases 20°. Water contact angle decreases about 12° when 9% of silanol groups on Q(3) surface are deprotonated. When the deprotonation degree increases to 50%, water contact angle decreases to 0. The dependence of wettability on silica surface functional groups was used to analyze contact angle measurement ambiguity in literature. The composition of silica surfaces is complicated under CO2 sequestration conditions, the results found in this study may help to better understand wettability of CO2/brine/silica system. PMID:26509282
Cardiac motion correction based on partial angle reconstructed images in x-ray CT
Energy Technology Data Exchange (ETDEWEB)
Kim, Seungeon; Chang, Yongjin; Ra, Jong Beom, E-mail: jbra@kaist.ac.kr [Department of Electrical Engineering, KAIST, Daejeon 305-701 (Korea, Republic of)
2015-05-15
Purpose: Cardiac x-ray CT imaging is still challenging due to heart motion, which cannot be ignored even with the current rotation speed of the equipment. In response, many algorithms have been developed to compensate remaining motion artifacts by estimating the motion using projection data or reconstructed images. In these algorithms, accurate motion estimation is critical to the compensated image quality. In addition, since the scan range is directly related to the radiation dose, it is preferable to minimize the scan range in motion estimation. In this paper, the authors propose a novel motion estimation and compensation algorithm using a sinogram with a rotation angle of less than 360°. The algorithm estimates the motion of the whole heart area using two opposite 3D partial angle reconstructed (PAR) images and compensates the motion in the reconstruction process. Methods: A CT system scans the thoracic area including the heart over an angular range of 180° + α + β, where α and β denote the detector fan angle and an additional partial angle, respectively. The obtained cone-beam projection data are converted into cone-parallel geometry via row-wise fan-to-parallel rebinning. Two conjugate 3D PAR images, whose center projection angles are separated by 180°, are then reconstructed with an angular range of β, which is considerably smaller than a short scan range of 180° + α. Although these images include limited view angle artifacts that disturb accurate motion estimation, they have considerably better temporal resolution than a short scan image. Hence, after preprocessing these artifacts, the authors estimate a motion model during a half rotation for a whole field of view via nonrigid registration between the images. Finally, motion-compensated image reconstruction is performed at a target phase by incorporating the estimated motion model. The target phase is selected as that corresponding to a view angle that is orthogonal to the center view angles of
Cardiac motion correction based on partial angle reconstructed images in x-ray CT
International Nuclear Information System (INIS)
Purpose: Cardiac x-ray CT imaging is still challenging due to heart motion, which cannot be ignored even with the current rotation speed of the equipment. In response, many algorithms have been developed to compensate remaining motion artifacts by estimating the motion using projection data or reconstructed images. In these algorithms, accurate motion estimation is critical to the compensated image quality. In addition, since the scan range is directly related to the radiation dose, it is preferable to minimize the scan range in motion estimation. In this paper, the authors propose a novel motion estimation and compensation algorithm using a sinogram with a rotation angle of less than 360°. The algorithm estimates the motion of the whole heart area using two opposite 3D partial angle reconstructed (PAR) images and compensates the motion in the reconstruction process. Methods: A CT system scans the thoracic area including the heart over an angular range of 180° + α + β, where α and β denote the detector fan angle and an additional partial angle, respectively. The obtained cone-beam projection data are converted into cone-parallel geometry via row-wise fan-to-parallel rebinning. Two conjugate 3D PAR images, whose center projection angles are separated by 180°, are then reconstructed with an angular range of β, which is considerably smaller than a short scan range of 180° + α. Although these images include limited view angle artifacts that disturb accurate motion estimation, they have considerably better temporal resolution than a short scan image. Hence, after preprocessing these artifacts, the authors estimate a motion model during a half rotation for a whole field of view via nonrigid registration between the images. Finally, motion-compensated image reconstruction is performed at a target phase by incorporating the estimated motion model. The target phase is selected as that corresponding to a view angle that is orthogonal to the center view angles of
Time dependent correlation between dihedral angles as probe for long range communication in proteins
Das, Amit; Ghosh, Mahua; Chakrabarti, J.
2016-02-01
We calculate the time dependent correlation functions (TDCF) between the dihedral angles of a protein calmodulin (CaM), an important protein involved in calcium ion binding in eukaryotic cells. The linker between the calcium binding domains of CaM shows structural changes due to calcium binding at far distances which enables the protein to function. We show that the TDCF between the dihedral angles in these regions are correlated temporally prior to ion binding which are lost upon ion binding. Thus the TDCFs connect the structural changes with ion binding, and can be useful to understand coupled phenomena in bio-macromolecules.
Characterization of angle – dependent Focal spot in a miniature X-ray tube
International Nuclear Information System (INIS)
Miniature x-ray tube can be used to obtain important images easily due to its small size and movability. Because the miniature x-ray tube discussed in this paper is a transmission type, it can emit x-rays in all directions, making it possible to take angle-dependent images. Focal spot is essential in an x-ray tube because it affects the quality of images taken by the x-ray tube. The size of the focal spot is equivalent to that of the x-ray generation region located at the x-ray tube target. If the size of focal spot is too large, images produced will be blurry. In other words, smaller focal spots produce clearer images. Currently common x-ray tubes have a relatively thick target, causing them to emit x-rays in one direction with uniform focal spot size. This type of x-ray produced is called reflection x-ray. However, unlike the conventional, miniature x-ray tubes, that this paper focuses on, have thin beryllium targets, allowing for both reflection x-ray and transmission x-ray to be generated at the targets. And since both types can affect the size of focal spots, these miniature x-ray tubes can emit x-rays, which is a crucial property when taking angle-dependent images. By measuring the physical characteristics of the focal spots, methods of improving the qualities of angle-dependent images can be determined. Thus, this experiment, which deals with measuring these physical characteristics will substantially help in the improvement of the qualities of angle-dependent images. The result was obtained by analyzing the image with procedure provided by EN-12543-5 Focal spots increase with increase in angle from 0 degree to 90 degrees
Magnetic aspect angle dependence of spectra from coherent radio aurora backscatter
International Nuclear Information System (INIS)
In 1981, a multiple path radar system was operated on the Canadian prairies with three 50-MHz transmitters and two receivers all separately located such as to establish six backscatter links. The radar beams illuminated the same scatter volume in the ionospheric E layer. Four of these links produced coherent backscatter signals from 3-m wavelength irregularities under different magnetic aspect angles ranging from 1.5 degree to 5.9 degree (reference height 110 km), but under almost identical drift flow angles. The radars were operated in the CW mode which yielded high time and spectral resolution but only moderate spatial resolution. In order to avoid confusion between spectral peaks from different locations within the backscatter volume, only single peaked spectra have been analyzed and compared. The Doppler shifts of both type I and type II spectra exhibit an aspect angle dependence which is much weaker than that predicted by existing linear and nonlinear theories
International Nuclear Information System (INIS)
We theoretically discuss the magnetic-field-angle dependence of the zero-energy density of states (ZEDOS) in superconductors. Point-node and line-node superconducting gaps on spherical and cylindrical Fermi surfaces are considered. The Doppler-shift (DS) method and the Kramer-Pesch approximation (KPA) are used to calculate the ZEDOS. Numerical results show that consequences of the DS method are corrected by the KPA.
Effect of Mono- and Multivalent Salts on Angle-dependent Attractions between Charged Rods
Lee, Kun-Chun; Borukhov, Itamar; Gelbart, William M.; Liu, Andrea J.; Stevens, Mark J.
2003-01-01
Using molecular dynamics simulations we examine the effective interactions between two like-charged rods as a function of angle and separation. In particular, we determine how the competing electrostatic repulsions and multivalent-ion-induced attractions depend upon concentrations of simple and multivalent salt. We find that with increasing multivalent salt the stable configuration of two rods evolves from isolated rods to aggregated perpendicular rods to aggregated parallel rods; at sufficie...
A. Tarantello; G. Martone; Bizzarri, B.; A. Caporossi
2012-01-01
To investigate the safety, the efficacy and stability of the AcrySof phakic angle-supported intraocular lens (IOL) (Alcon Laboratories, Inc., Fort Worth, TX) for correction of moderate-to-high myopia in adults. 12 patients (18 eyes) with moderate-to-high myopia underwent implantation of the AcrySof phakic angle-supported IOL. Best spectacle-corrected visual acuity (BSCVA), uncorrected distance visual acuity (UCVA), predictability and stability of mean manifest refraction spherical equivalent ...
View-angle-dependent AIRS Cloudiness and Radiance Variance: Analysis and Interpretation
Gong, Jie; Wu, Dong L.
2013-01-01
Upper tropospheric clouds play an important role in the global energy budget and hydrological cycle. Significant view-angle asymmetry has been observed in upper-level tropical clouds derived from eight years of Atmospheric Infrared Sounder (AIRS) 15 um radiances. Here, we find that the asymmetry also exists in the extra-tropics. It is larger during day than that during night, more prominent near elevated terrain, and closely associated with deep convection and wind shear. The cloud radiance variance, a proxy for cloud inhomogeneity, has consistent characteristics of the asymmetry to those in the AIRS cloudiness. The leading causes of the view-dependent cloudiness asymmetry are the local time difference and small-scale organized cloud structures. The local time difference (1-1.5 hr) of upper-level (UL) clouds between two AIRS outermost views can create parts of the observed asymmetry. On the other hand, small-scale tilted and banded structures of the UL clouds can induce about half of the observed view-angle dependent differences in the AIRS cloud radiances and their variances. This estimate is inferred from analogous study using Microwave Humidity Sounder (MHS) radiances observed during the period of time when there were simultaneous measurements at two different view-angles from NOAA-18 and -19 satellites. The existence of tilted cloud structures and asymmetric 15 um and 6.7 um cloud radiances implies that cloud statistics would be view-angle dependent, and should be taken into account in radiative transfer calculations, measurement uncertainty evaluations and cloud climatology investigations. In addition, the momentum forcing in the upper troposphere from tilted clouds is also likely asymmetric, which can affect atmospheric circulation anisotropically.
T1rho mapping of entire femoral cartilage using depth- and angle-dependent analysis
International Nuclear Information System (INIS)
To create and evaluate normalized T1rho profiles of the entire femoral cartilage in healthy subjects with three-dimensional (3D) angle- and depth-dependent analysis. T1rho images of the knee from 20 healthy volunteers were acquired on a 3.0-T unit. Cartilage segmentation of the entire femur was performed slice-by-slice by a board-certified radiologist. The T1rho depth/angle-dependent profile was investigated by partitioning cartilage into superficial and deep layers, and angular segmentation in increments of 4 over the length of segmented cartilage. Average T1rho values were calculated with normalized T1rho profiles. Surface maps and 3D graphs were created. T1rho profiles have regional and depth variations, with no significant magic angle effect. Average T1rho values in the superficial layer of the femoral cartilage were higher than those in the deep layer in most locations (p < 0.05). T1rho values in the deep layer of the weight-bearing portions of the medial and lateral condyles were lower than those of the corresponding non-weight-bearing portions (p < 0.05). Surface maps and 3D graphs demonstrated that cartilage T1rho values were not homogeneous over the entire femur. Normalized T1rho profiles from the entire femoral cartilage will be useful for diagnosing local or early T1rho abnormalities and osteoarthritis in clinical applications. (orig.)
T1rho mapping of entire femoral cartilage using depth- and angle-dependent analysis
Energy Technology Data Exchange (ETDEWEB)
Nozaki, Taiki; Kaneko, Yasuhito; Yu, Hon J.; Yoshioka, Hiroshi [University of California Irvine, Department of Radiological Sciences, Orange, CA (United States); Kaneshiro, Kayleigh [University of California Irvine, School of Medicine, Irvine, CA (United States); Schwarzkopf, Ran [University of California Irvine, Department of Orthopedic Surgery, Irvine, CA (United States); Hara, Takeshi [Gifu University Graduate School of Medicine, Department of Intelligent Image Information, Division of Regeneration and Advanced Medical Sciences, Gifu (Japan)
2016-06-15
To create and evaluate normalized T1rho profiles of the entire femoral cartilage in healthy subjects with three-dimensional (3D) angle- and depth-dependent analysis. T1rho images of the knee from 20 healthy volunteers were acquired on a 3.0-T unit. Cartilage segmentation of the entire femur was performed slice-by-slice by a board-certified radiologist. The T1rho depth/angle-dependent profile was investigated by partitioning cartilage into superficial and deep layers, and angular segmentation in increments of 4 over the length of segmented cartilage. Average T1rho values were calculated with normalized T1rho profiles. Surface maps and 3D graphs were created. T1rho profiles have regional and depth variations, with no significant magic angle effect. Average T1rho values in the superficial layer of the femoral cartilage were higher than those in the deep layer in most locations (p < 0.05). T1rho values in the deep layer of the weight-bearing portions of the medial and lateral condyles were lower than those of the corresponding non-weight-bearing portions (p < 0.05). Surface maps and 3D graphs demonstrated that cartilage T1rho values were not homogeneous over the entire femur. Normalized T1rho profiles from the entire femoral cartilage will be useful for diagnosing local or early T1rho abnormalities and osteoarthritis in clinical applications. (orig.)
Directory of Open Access Journals (Sweden)
Mohit Raghuwanshi
2013-02-01
Full Text Available Herein we numerically study the excitation angle-dependant far-field and near-field optical properties of vertical plasmonic nanowires arranged in an unconventional linear geometry: Fibonacci number chain. The first five numbers in the Fibonacci series (1, 1, 2, 3, 5 were mapped to the size of gold nanowires, and arranged in a linear chain to study their optical interactions, and compared them to conventional chain of vertical gold nanowires. By harnessing the radiative and evanescent coupling regimes in the geometry, we found a systematic variation in the far-field extinction and near-field confinement in the geometries. Our simulation studies revealed enhanced backscattered intensity in the far-field radiation pattern at excitation angles along the chain-length of Fibonacci geometry, which was otherwise absent for conventional chain of plasmonic nanowires. Such angular reconfiguration of optical fields in unconventional linear geometries can be harnessed for tunable on-chip plasmonics.
Directory of Open Access Journals (Sweden)
A.-P. Hyvärinen
2013-01-01
Full Text Available The Multi-Angle Absorption Photometer (MAAP is a widely-used instrument for aerosol black carbon (BC measurements. In this paper, we show correction methods for an artifact found to affect the instrument accuracy in environments characterized by high black carbon concentrations. The artifact occurs after a filter spot change – as BC mass is accumulated on a fresh filter spot, the attenuation of the light (raw signal is weaker than anticipated. This causes a sudden decrease, followed by a gradual increase in measured BC concentration. The artifact is present in the data when the BC concentration exceeds ~3 μg m^{−3} at the typical MAAP flow rate of 16.7 L min^{−1} or 1 m^{3} h^{−1}. The artifact is caused by erroneous dark counts in the photodetector measuring the transmitted light, in combination with an instrument internal averaging procedure of the photodetector raw signals. It was found that, in addition to the erroneous temporal response of the data, concentrations higher than 9 μg m^{−3} (at the flow rate of 16.7 L min^{−1} are underestimated by the MAAP. The underestimation increases with increasing BC accumulation rate. At a flow rate of 16.7 L min^{−1} and concentration of about 24 μg m^{−3} (BC accumulation rate ~0.4 μg min^{−1}, the underestimation is about 30%. There are two ways of overcoming the MAAP artifact. One method is by logging the raw signal of the 165° photomultiplier measuring the reflected light from the filter spot. As this signal is not affected by the artifact, it can be converted to approximately correct absorption and BC values. However, as the typical print formats of the MAAP do not give the reflected signal as an output, a semi-empirical correction method was developed based on laboratory experiments to correct for the results in the post-processing phase. The correction function was applied to three MAAP datasets from
Directory of Open Access Journals (Sweden)
A.-P. Hyvärinen
2012-09-01
Full Text Available The Multi-Angle Absorption Photometer (MAAP is a widely-used instrument for aerosol black carbon observations. In this paper, we show correction methods for an artifact found to affect the instrument accuracy in environments with high black carbon concentrations. The artifact occurs after a filter spot change – as BC mass is accumulated on a fresh filter spot, the attenuation of the light (raw signal is weaker than anticipated. This causes a sudden decrease, followed by a gradual increase in measured BC concentration. The artifact is present in the data when the BC concentration exceeds ∼3 μg m^{−3} at the typical MAAP flow rate of 16.7 l min^{−1} or 1 m^{3} h^{−1}. The artifact is caused by erroneous dark counts in the photo detector measuring the transmitted light, in combination with an instrument internal averaging procedure of the photo detector raw signals. It was found that in addition to the erroneous temporal response of the data, concentrations higher than 9 μg m^{−3} (at the flow rate of 16.7 l min^{−1} are underestimated by the MAAP. The underestimation increases with increasing BC accumulation rate. At a flow rate of 16.7 l min^{−1} and concentration of about 24 μg m^{−3} (BC accumulation rate ∼0.4 μg min^{−1}, the underestimation is about 30%. There are two ways of overcoming the MAAP artifact. One method is by logging the raw signal of the 165° photomultiplier measuring the reflected light from the filter spot. As this signal is not affected by the artifact, it can be converted to approximately correct absorption and BC values. However, as the typical print formats of the MAAP do not give the reflected signal as an output, a semi-empirical correction method was developed based on laboratory experiments to correct for the results in the post-processing phase. The correction function was applied to three MAAP datasets from Gual Pahari
The tunneling magnetoresistance current dependence on cross sectional area, angle and temperature
Energy Technology Data Exchange (ETDEWEB)
Zhang, Z. H., E-mail: zhaohui@physics.umanitoba.ca; Bai, Lihui; Hu, C.-M. [Department of Physics and Astronomy, University of Manitoba, Winnipeg, R3T 2N2 Canada (Canada); Hemour, S.; Wu, K. [École Polytechnique de Montréal, Montréal, H3T 1J4 Canada (Canada); Fan, X. L.; Xue, D. S. [The Key Lab for Magnetism and Magnetic Materials of Ministry of Education, Lanzhou University, Lanzhou 730000 (China); Houssameddine, D. [Everspin Technologies, 1347 N. Alma School Road, Chandler, Arizona 85224 (United States)
2015-03-15
The magnetoresistance of a MgO-based magnetic tunnel junction (MTJ) was studied experimentally. The magnetoresistance as a function of current was measured systematically on MTJs for various MgO cross sectional areas and at various temperatures from 7.5 to 290.1 K. The resistance current dependence of the MTJ was also measured for different angles between the two ferromagnetic layers. By considering particle and angular momentum conservation of transport electrons, the current dependence of magnetoresistance can be explained by the changing of spin polarization in the free magnetic layer of the MTJ. The changing of spin polarization is related to the magnetoresistance, its angular dependence and the threshold current where TMR ratio equals zero. A phenomenological model is used which avoid the complicated barrier details and also describes the data.
Electron mean free path from angle-dependent photoelectron spectroscopy of aerosol particles
Goldmann, Maximilian; West, Adam H C; Yoder, Bruce L; Signorell, Ruth
2015-01-01
We propose angle-resolved photoelectron spectroscopy of aerosol particles as an alternative way to determine the electron mean free path of low energy electrons in solid and liquid materials. The mean free path is obtained from fits of simulated photoemission images to experimental ones over a broad range of different aerosol particle sizes. The principal advantage of the aerosol approach is twofold. Firstly, aerosol photoemission studies can be performed for many different materials, including liquids. Secondly, the size-dependent anisotropy of the photoelectrons can be exploited in addition to size-dependent changes in their kinetic energy. These finite size effects depend in different ways on the mean free path and thus provide more information on the mean free path than corresponding liquid jet, thin film, or bulk data. The present contribution is a proof of principle employing a simple model for the photoemission of electrons and preliminary experimental data for potassium chloride aerosol particles.
Electron mean free path from angle-dependent photoelectron spectroscopy of aerosol particles
International Nuclear Information System (INIS)
We propose angle-resolved photoelectron spectroscopy of aerosol particles as an alternative way to determine the electron mean free path of low energy electrons in solid and liquid materials. The mean free path is obtained from fits of simulated photoemission images to experimental ones over a broad range of different aerosol particle sizes. The principal advantage of the aerosol approach is twofold. First, aerosol photoemission studies can be performed for many different materials, including liquids. Second, the size-dependent anisotropy of the photoelectrons can be exploited in addition to size-dependent changes in their kinetic energy. These finite size effects depend in different ways on the mean free path and thus provide more information on the mean free path than corresponding liquid jet, thin film, or bulk data. The present contribution is a proof of principle employing a simple model for the photoemission of electrons and preliminary experimental data for potassium chloride aerosol particles
Angle-resolved photoemission study of Si electronic structure: Boron concentration dependence
International Nuclear Information System (INIS)
The boron concentration dependence of the Si electronic structure of Si(1 0 0)2 x 1 surfaces were investigated by angle-resolved photoemission spectroscopy (ARPES). The ARPES spectra exhibit rigid shifts toward lower binding energy as the boron concentration increases. The band dispersion was obtained from fitting procedure, and it is found that the top of the valence band does not exceed the Fermi level even with a boron concentration 35 times larger than the critical concentration of the metal-insulator transition.
Wang, Zhuo; Li, Yang-Bo; Bai, Feng; Wang, Cheng-Wei; Zhao, Quan-Zhong
2016-07-01
Lubricated tribological properties of stainless steel were investigated by femtosecond laser surface texturing. Regular-arranged micro-grooved textures with different spacing and micro-groove inclination angles (between micro-groove path and sliding direction) were produced on AISI 304L steel surfaces by an 800 nm femtosecond laser. The spacing of micro-groove was varied from 25 to 300 μm, and the inclination angles of micro-groove were measured as 90° and 45°. The tribological properties of the smooth and textured surfaces with micro-grooves were investigated by reciprocating ball-on-flat tests against Al2O3 ceramic balls under starved oil lubricated conditions. Results showed that the spacing of micro-grooves significantly affected the tribological property. With the increase of micro-groove spacing, the average friction coefficients and wear rates of textured surfaces initially decreased then increased. The tribological performance also depended on the inclination angles of micro-grooves. Among the investigated patterns, the micro-grooves perpendicular to the sliding direction exhibited the lowest average friction coefficient and wear rate to a certain extent. Femtosecond laser-induced surface texturing may remarkably improve friction and wear properties if the micro-grooves were properly distributed.
Directory of Open Access Journals (Sweden)
Isham
2005-01-01
Full Text Available When the Earth's ionosphere is irradiated by a radiofrequency (RF electromagnetic wave of sufficiently high power density and tuned to match a natural E- or F-region plasma frequency, ionospheric magnetoionic wave modes may be excited and may generate RF electromagnetic sideband waves via nonlinear interactions. These secondary emissions, which may then escape from the ionosphere, have been termed stimulated electromagnetic emission or SEE. The frequency spectra of this radiation has been studied extensively, and a number of characteristic spectral features have been identified and in some cases related to particular plasma processes. The separation in frequency between the RF pump and the harmonics of the local electron gyrofrequency is critical in determining the amount of anomalous absorption suffered by the pump wave and the spectral properties of the stimulated sidebands. The pump can excite electrostatic waves which do not propagate away but can in some cases be observed via radio-wave scattering from the electron density fluctuations associated with them. These enhanced density fluctuations are created by processes commonly referred to as upper-hybrid and Langmuir turbulence. Langmuir turbulence has been the subject of 930-MHz scattering observations with antenna scanning through several pre-selected angles between the geographic and geomagnetic zenith directions, and a preference for pointing angles between the Spitze angle and geomagnetic field-aligned was identified. Other phenomena, such as the generation of enhanced electron temperatures and artificial aurora, have more recently been shown to have special behavior at similar angles, near but apparently not quite at field-aligned. In view of this evidence for angular structure in several pump-induced effects, in light of the rich variety of SEE phenomena strongly dependent on the geomagnetic field via the frequency interval between the pump and the gyrofrequency harmonics, and in
International Nuclear Information System (INIS)
The (π, π) shadow band (SB) in the La-based cuprate family (La214) was studied by angle-resolved photoemission spectroscopy over a wide doping range from x=0.01 to x=0.25. Unlike the well-studied case of the Bi-based cuprate family, an overall strong, monotonic doping dependence of the SB intensity at the Fermi level (EF) was observed. In contrast to a previous report for the presence of the SB only close to x=1/8, we found that it exists in a wide doping range, associated with a doping-independent (π, π) wave vector but a strongly doping-dependent intensity: it is strongest at x∼0.03 and systematically diminishes as the doping increases until it becomes negligible in the overdoped regime. This SB with the observed doping dependence of intensity can in principle be caused by the antiferromagnetic fluctuations or a particular form of low-temperature orthorhombic lattice distortion known to persist up to x∼0.21 in the system, with both being weakened with increasing doping. However, a detailed binding-energy-dependent analysis of the SB at x=0.07 does not appear to support the former interpretation, leaving the latter as a more plausible candidate, despite a challenge in quantitatively linking the doping dependences of the SB intensity and the magnitude of the lattice distortion. Our finding highlights the necessity for a careful and global consideration of the inherent structural complications for correctly understanding the cuprate Fermiology and its microscopic implication.
International Nuclear Information System (INIS)
We develop a theoretical description of Dynamic Nuclear Polarization (DNP) in solids under Magic Angle Spinning (MAS) to describe the magnetic field dependence of the DNP effect. The treatment is based on an efficient scheme for numerical solution of the Liouville-von Neumann equation, which explicitly takes into account the variation of magnetic interactions during the sample spinning. The dependence of the cross-effect MAS-DNP on various parameters, such as the hyperfine interaction, electron-electron dipolar interaction, microwave field strength, and electron spin relaxation rates, is analyzed. Electron spin relaxation rates are determined by electron paramagnetic resonance measurements, and calculations are compared to experimental data. Our results suggest that the observed nuclear magnetic resonance signal enhancements provided by MAS-DNP can be explained by discriminating between “bulk” and “core” nuclei and by taking into account the slow DNP build-up rate for the bulk nuclei
Future Constraints on Angle-Dependent Non-Gaussianity from Large Radio Surveys
Raccanelli, Alvise; Bartolo, Nicola; Bertacca, Daniele; Liguori, Michele; Matarrese, Sabino; Norris, Ray P; Parkinson, David
2015-01-01
We investigate how well future large-scale radio surveys could measure different shapes of primordial non-Gaussianity; in particular we focus on angle-dependent non-Gaussianity arising from primordial anisotropic sources, whose bispectrum has an angle dependence between the three wavevectors that is characterized by Legendre polynomials $\\mathcal{P}_L$ and expansion coefficients $c_L$. We provide forecasts for measurements of galaxy power spectrum, finding that Large-Scale Structure (LSS) data could allow measurements of primordial non-Gaussianity competitive or improving upon current constraints set by CMB experiments, for all the shapes considered. We argue that the best constraints will come from the possibility to assign redshift information to radio galaxy surveys, and investigate a few possible scenarios for the EMU and SKA surveys. A realistic (futuristic) modeling could provide constraints of $f_{\\rm NL}^{\\rm loc} \\approx 1 (0.5)$ for the local shape, $f_{\\rm NL}$ of $\\mathcal{O}(10) (\\mathcal{O}(1))$...
Multiplicity dependent and non-binomial efficiency corrections for particle number cumulants
Bzdak, Adam; Koch, Volker
2016-01-01
In this note we extend previous work on efficiency corrections for cumulant measurements [1,2]. We will discuss the limitations of the methods presented in these papers. Specifically we will consider multiplicity dependent efficiencies as well as a non-binomial efficiency distributions. We will discuss the most simple and straightforward methods to implement those corrections.
International Nuclear Information System (INIS)
The decrease in output parameters of polycrystalline silicon (CAST) solar cells with increasing angle of incidence has been investigated. The distribution of the surface photon, reflection losses and effective junction depth are modeled, by taking in the front surface recombination velocity< It is shown that that angle of incidence radiation is depended on the increase of the surface recombination velocity.(Author)
International Nuclear Information System (INIS)
Purpose: Dosimetry in computed tomography (CT) is increasingly based on Monte Carlo studies that define the dose in the patient (in mGy) as a function of air kerma (free in air) at isocenter (mGy). The accuracy of Monte Carlo studies depends in part on the accuracy of the characterization of the bow tie filter for a given CT scanner model. A simple method for characterizing the bow tie filter attenuation profile in CT scanners would therefore be very useful. The theory behind such a method is proposed. Methods: A measurement protocol is discussed mathematically and demonstrated using computer simulation. The proposed method requires the placement of a radiation monitor at the periphery of the CT field, and the time domain signal (kerma rate versus time) is measured with good temporal resolution (∼200 Hz or better) and with all other objects (e.g., patient couch) retracted from the field of view. Knowledge of the source to isocenter distance (or alternately, the isocenter to probe distance) is required. The stationary detector records the kerma rate versus time signal as the gantry rotates through several revolutions. From this temporal data, signal processing techniques are used to extract in-phase peaks, as well as out-of-phase kerma rate levels. From these data, the distance from isocenter to the probe can be determined (or, alternatively, the source to isocenter distance), and the angle-dependent bow tie filter attenuation can be computed. By measuring the angle-dependent bow tie filter attenuation at several kVp settings, the bow tie composition versus fan angle can be computed using basis decomposition techniques. Results: The simulations illustrated that with 2% added noise in the kerma rate versus time signal, the attenuation properties of a hypothetical two component (aluminum and polymethyl methacrylate) bow tie filter could be determined (r2>0.99). Although the computed basis material thicknesses were not exactly equal to the actual thicknesses, their
Analytical Model for Estimating the Zenith Angle Dependence of Terrestrial Cosmic Ray Fluxes
Sato, Tatsuhiko
2016-01-01
A new model called “PHITS-based Analytical Radiation Model in the Atmosphere (PARMA) version 4.0” was developed to facilitate instantaneous estimation of not only omnidirectional but also angular differential energy spectra of cosmic ray fluxes anywhere in Earth’s atmosphere at nearly any given time. It consists of its previous version, PARMA3.0, for calculating the omnidirectional fluxes and several mathematical functions proposed in this study for expressing their zenith-angle dependences. The numerical values of the parameters used in these functions were fitted to reproduce the results of the extensive air shower simulation performed by Particle and Heavy Ion Transport code System (PHITS). The angular distributions of ground-level muons at large zenith angles were specially determined by introducing an optional function developed on the basis of experimental data. The accuracy of PARMA4.0 was closely verified using multiple sets of experimental data obtained under various global conditions. This extension enlarges the model’s applicability to more areas of research, including design of cosmic-ray detectors, muon radiography, soil moisture monitoring, and cosmic-ray shielding calculation. PARMA4.0 is available freely and is easy to use, as implemented in the open-access EXcel-based Program for Calculating Atmospheric Cosmic-ray Spectrum (EXPACS). PMID:27490175
Currey, J D; Brear, K; Zioupos, P
1994-07-01
The successful modelling of the mechanical properties of mineralized tissues depends critically on the knowledge of the off-axis behaviour of individual unidirectional lamellae. Information on this is lacking. In this work we attempt to rectify the situation. Young's modulus, measured in bending and tension, and the tensile strength and ultimate strain to failure of the dentine of the narwhal Monodon monoceros, were determined on specimens that had almost unidirectional fibres, whose direction differed considerably from specimen to specimen. Modulus and strength decreased steadily with the degree of off-angle loading, falling to about 45% of maximum for modulus, and 35% of maximum for strength. Ultimate strain showed a less uniform behaviour, and remained remarkably high at large angles. Differences in mechanical behaviour were not related to the very small differences in mineral content measured between specimens. These findings have strong implications for modelling the anisotropic behaviour of bone, because dentine is very much like bone in most important respects. Predictions using classical composite theory are reasonably satisfactory, as long as the mineral crystals are assumed to be platelets, not rods. PMID:8063839
International Nuclear Information System (INIS)
An angle-dependent X-ray photoelectron spectroscopy (XPS) method used to measure the thickness of molecularly thin lubricants was developed. The method was built based on an island model of patched overlayer on a flat substrate by using the photoemission signal solely from the lubricant film. Typical molecularly thin Zdol films on the CHx overcoat of unused commercial magnetic disks were measured to verify the metrology. The lubricant thickness determined by the metrology was equal to the recent result by thermostatic high vacuum atomic force microscopy. The measured deduction in the thickness of the molecularly thin lubricant films, successively irradiated by the monochromatic source operated at 14 kV/250 W, was as low as 1 A during the first irradiation hour. XPS spectra showed that no hydrocarbons, water or oxygen were adsorbed over the Zdol outer surfaces in the tested XPS conditions. The inelastic mean free path (IMFP) of C 1s in Zdol or in CHx was found to be independent of take off angle (TOA) when TOA o. The IMFP of C 1s in Zdol was ∼63.5 A and the lubricant island thickness was ∼35 A
Analytical Model for Estimating the Zenith Angle Dependence of Terrestrial Cosmic Ray Fluxes.
Sato, Tatsuhiko
2016-01-01
A new model called "PHITS-based Analytical Radiation Model in the Atmosphere (PARMA) version 4.0" was developed to facilitate instantaneous estimation of not only omnidirectional but also angular differential energy spectra of cosmic ray fluxes anywhere in Earth's atmosphere at nearly any given time. It consists of its previous version, PARMA3.0, for calculating the omnidirectional fluxes and several mathematical functions proposed in this study for expressing their zenith-angle dependences. The numerical values of the parameters used in these functions were fitted to reproduce the results of the extensive air shower simulation performed by Particle and Heavy Ion Transport code System (PHITS). The angular distributions of ground-level muons at large zenith angles were specially determined by introducing an optional function developed on the basis of experimental data. The accuracy of PARMA4.0 was closely verified using multiple sets of experimental data obtained under various global conditions. This extension enlarges the model's applicability to more areas of research, including design of cosmic-ray detectors, muon radiography, soil moisture monitoring, and cosmic-ray shielding calculation. PARMA4.0 is available freely and is easy to use, as implemented in the open-access EXcel-based Program for Calculating Atmospheric Cosmic-ray Spectrum (EXPACS). PMID:27490175
2015-11-01
In the article by Heuslein et al, which published online ahead of print on September 3, 2015 (DOI: 10.1161/ATVBAHA.115.305775), a correction was needed. Brett R. Blackman was added as the penultimate author of the article. The article has been corrected for publication in the November 2015 issue. PMID:26490278
Entrance channel dependence of back angle yields: orbiting in 24Mg+16O reaction
International Nuclear Information System (INIS)
The back-angle yields of the oxygen and carbon particles from the 24Mg+16O reaction have been measured at E/sub Lab/(24Mg) = 79.5 MeV by using reverse kinematics. Comparison with data for the 28Si+12C reaction forming the same compound nucleus at the same excitation energy and with very similar spin distribution, demonstrates a strong entrance channel effect which is favoring the break-up into the entrance channel with large excitation energy. This result qualitatively supports the picture of the formation of a long-lived orbiting complex whose structure and decay are dependent on the entrance channel. The compound nucleus contribution has been inferred to be less than 15% of the measured oxygen cross-section. 9 references
Azimuthal angle- and scanning pitch-dependent colorization of metals by ultrashort laser pulses
Li, Yangbo; Qian, Jing; Bai, Feng; Wang, Zhuo; Wang, Chengwei; Fan, Wenzhong; Zhang, Yang; Zhao, Quanzhong
2016-04-01
We report the modification of optical properties of 304 stainless steel surfaces by femtosecond laser direct writing with different scanning pitches. Regularly arranged ripples with a spatial period of ~700 nm were obtained, rendering vivid structural colors when we illuminated the surface with white light. Diffraction spectra were generated to investigate the spectral properties of the structural colors. Results indicate that the diffraction maximum strongly depends on scanning pitch and azimuthal angle, but that the central wavelength is insensitive to both of them. The reflectance properties were also investigated. This study adds a new parameter, the scanning pitch, to the list of parameters in the production of controllable colorized metal, which may find a range of applications in color display, decoration, and so on.
Incident-angle dependent color tuning from a single plasmonic chip
International Nuclear Information System (INIS)
We report on a broad color tuning effect covering the visible range from a single plasmonic chip. By simply tilting the orientation of the designed plasmonic chip within a certain range, the photon–plasmon coupling interactions between the incident light and the plasmonic nanostructures on the chip can be finely tuned, resulting in an angle-dependent continuous color filtering effect. The physical mechanism of the device is investigated through the full-wave calculations, which provide important guidance for the design and optimization of the proposed devices. The broad color tuning from the demonstrated single chip will potentially benefit visualization and display technologies, and is particularly useful for the construction of reflection-based spatial light modulators. (paper)
Inclusion of temperature dependent shell corrections in Landau theory for hot rotating nuclei
Indian Academy of Sciences (India)
G Shanmugam; P Arumugam
2001-07-01
Landau theory used for studying hot rotating nuclei usually uses zero temperature Strutinsky smoothed total energy for the temperature dependent shell corrections. This is replaced in this work by the temperature dependent Strutinsky smoothed free energy. Our results show that this replacement has only marginal effect for temperatures greater than 1 MeV but plays signiﬁcant role at lower temperatures.
Angle dependent Fiber Bragg grating inscription in microstructured polymer optical fibers
DEFF Research Database (Denmark)
Bundalo, Ivan-Lazar; Nielsen, Kristian; Bang, Ole
2015-01-01
We report on an incidence angle influence on inscription of the Fiber Bragg Gratings in Polymethyl methacrylate (PMMA) microstructured polymer optical fibers. We have shown experimentally that there is a strong preference of certain angles, labeled Gamma K, over the other ones. Angles close to...... Marshall et al. (C)2015 Optical Society of America...
Paccola, Cleber Antonio Jansen
2015-01-01
The step-by-step preoperative planning for supracondylar opening wedge osteotomy of the femur for precise correction of the load axis of the lower limb using a fixed-angle implant (95° AO blade plate) is presented. The surgical technique and the use of a bone graft from the same site for filling in the defect are also presented.
Takemura, Akihiro; Togawa, Kumiko; Yokoi, Tomohiro; Ueda, Shinichi; Noto, Kimiya; Kojima, Hironori; Isomura, Naoki; Kumano, Tomoyasu
2016-07-01
In volumetric modulated arc therapy (VMAT) for prostate cancer, a positional and rotational error correction is performed according to the position and angle of the prostate. The correction often involves body leaning, and there is concern regarding variation in the dose distribution. Our purpose in this study was to evaluate the impact of body pitch rotation on the dose distribution regarding VMAT. Treatment plans were obtained retrospectively from eight patients with prostate cancer. The body in the computed tomography images for the original VMAT plan was shifted to create VMAT plans with virtual pitch angle errors of ±1.5° and ±3°. Dose distributions for the tilted plans were recalculated with use of the same beam arrangement as that used for the original VMAT plan. The mean value of the maximum dose differences in the dose distributions between the original VMAT plan and the tilted plans was 2.98 ± 0.96 %. The value of the homogeneity index for the planning target volume (PTV) had an increasing trend according to the pitch angle error, and the values of the D 95 for the PTV and D 2ml, V 50, V 60, and V 70 for the rectum had decreasing trends (p pitch angle error caused by body leaning had little effect on the dose distribution; in contrast, the pitch angle correction reduced the effects of organ displacement and improved these indexes. Thus, the pitch angle setup error in VMAT for prostate cancer should be corrected. PMID:26873139
Top mass dependent alpha_s^3 corrections to B-meson mixing in the MSSM
Virto, Javier
2011-01-01
We compute the top mass dependent NLO strong interaction matching conditions to the Delta F=2 effective Hamiltonian in the general MSSM. We study the relevance of such corrections, comparing its size with that of previously known NLO corrections in the limit mt->0, in scenarios with degeneracy, alignment, and hierarchical squarks. We find that, while these corrections are generally small, there are regions in the parameter space where the contributions to the Wilson coefficients C1 and C4 could partially overcome the expected suppression m_t/M_SUSY.
Dosimetric dependence on the collimator angle in prostate volumetric modulated arc therapy
Directory of Open Access Journals (Sweden)
Muhammad Isa
2014-12-01
Full Text Available Purpose: The purpose of this study is to investigate the dose-volume variations of planning target volume (PTV and organs-at-risk (OARs in prostate volumetric modulated arc therapy (VMAT when varying collimator angle. The collimator angle has the largest impact and is worth considering, so, its awareness is essential for a planner to produce an optimal prostate VMAT plan in a reasonable time frame. Methods: Single-arc VMAT plans at different collimator angles (0o, 15o, 30o, 45o, 60o, 75o and 90o were created systematically using a Harold heterogeneous pelvis phantom. The conformity index (CI, homogeneity index (HI, gradient index (GI, machine monitor units (MUs, dose-volume histogram and mean and maximum dose of the PTV were calculated and analyzed. On the other hand, the dose-volume histogram and mean and maximum doses of the OARs such as the bladder, rectum and femoral heads for different collimator angles were determined from the plans.Results: There was no significant difference, based on the planned dose-volume evaluation criteria, found in the VMAT optimizations for all studied collimator angles. A higher CI (0.53 and lower HI (0.064 were found in the 45o collimator angle. In addition, the 15o collimator angle provided a lower value of HI similar to the 45o collimator angle. Collimator angles of 75o and 90o were found to be good for rectum sparing, and collimator angles of 75o and 30o were found to be good for sparing of right and left femur, respectively. The PTV dose coverage for each plan was comparatively independent of the collimator angle. Conclusion: Our study indicates that the dosimetric results provide support and guidance to allow the clinical radiation physicists to make careful decisions in implementing suitable collimator angles to improve the PTV coverage and OARs sparing in prostate VMAT.
Nuclear level density formula with energy-dependent shell and pairing corrections
International Nuclear Information System (INIS)
A new phenomenological level density formula is based on the analytical expression of the single-particle state density. The main features of the proposed formula is the existence of not only the excitation-dependent shell correction energy but also the excitation-dependent pairing correction with the shell-pairing correlations (thus called SPC model), so far considered only by means of the microscopic Fermi-gas model, and no need of independent shell and pairing correction energy tables as often used for the previous formulas. At the ground states the shell and pairing corrections with the shell-pairing correlation terms are computed by using 6 constants for each shell, values of which are determined as to fit the empirical mass excess data. The analyses by using the observed s-wave neutron and proton resonance spacings of the mass range A=41-67 show that the prediction of the SPC model and its parameters will be superior to those of the previous models of the traditional Fermi-gas. This improvement seems to be due to the prescriptions of the excitation-dependent correction energies both for the shell and for the pairing effects. (author)
2016-02-01
In the article by Guessous et al (Guessous I, Pruijm M, Ponte B, Ackermann D, Ehret G, Ansermot N, Vuistiner P, Staessen J, Gu Y, Paccaud F, Mohaupt M, Vogt B, Pechère-Bertschi A, Martin PY, Burnier M, Eap CB, Bochud M. Associations of ambulatory blood pressure with urinary caffeine and caffeine metabolite excretions. Hypertension. 2015;65:691–696. doi: 10.1161/HYPERTENSIONAHA.114.04512), which published online ahead of print December 8, 2014, and appeared in the March 2015 issue of the journal, a correction was needed.One of the author surnames was misspelled. Antoinette Pechère-Berstchi has been corrected to read Antoinette Pechère-Bertschi.The authors apologize for this error. PMID:26763012
International Nuclear Information System (INIS)
A study is made of the corrections that are needed in the evaluation of the annual radiation dose, for use in TL/OSL-dating, via NaI(Tl) field gamma-ray spectrometry (monitoring of K, Th and U), calibrated via voluminous blocks that are simulating the Auger hole measuring conditions. Two cases are considered: the 'Heidelberg' granite calibration block, which was found to be 'quasi-infinite', and the 'Oxford' concrete calibration blocks, for which 'effective' concentrations of elements are reported so as to account for their 'non-infiniteness'. The calculations, via the software package ANGLE, are based on the concept of effective solid angles for Marinelli geometries. (author)
Directory of Open Access Journals (Sweden)
Mirica Karlovits
2015-03-01
Full Text Available Color-travel pigments, which exhibit much more extensive color change as well provide angle-dependent optical effect can be used in many industrial products. In present paper the multi-color effect pigment printed on three different foils with different background color (black, silver and transparent was investigated. The pigment was based on synthetically produced transparent silicon dioxide platelets coated with titanium dioxide. CIEL*a*b* values and reflection of prints were measured by multi-angle spectrophotometer at constant illumination at an angle of 45º and different viewing angles (-15º, 15°, 25º, 45º, 75º and 110º were used. The measurements of printed multi-color pigment showed that CIEL*a*b* color coordinates varied to great extents, depending on detection angles as well on color of the printing substrate. The study revealed that pigmnet printed on black background obtained significant change in color. The study has also shown that when viewing angle increases, the reflection curves decreases.
Time-dependent density-functional theory with self-interaction correction
Messud, J.; Dinh, P. M.; Reinhard, P.-G.; Suraud, E.
2007-01-01
We discuss an extension of time-dependent density-functional theory by a self-interaction correction (SIC). A strictly variational formulation is given taking care of the necessary constraints. A manageable and transparent propagation scheme using two sets of wavefunctions is proposed and applied to laser excitation with subsequent ionization of a dimer molecule.
Temperature Dependence Calibration and Correction of the DAMPE BGO Electromagnetic Calorimeter
Wei, Yifeng; Zhang, Yunlong; Wen, Sicheng; Wang, Chi; Li, Zhiying; Feng, Changqing; Wang, Xiaolian; Xu, Zizong; Huang, Guangshun; Liu, Shubin
2016-01-01
A BGO electromagnetic calorimeter (ECAL) is built for the DArk Matter Particle Explorer (DAMPE) mission. The effect of temperature on the BGO ECAL was investigated with a thermal vacuum experiment. The light output of a BGO crystal depends on temperature significantly. The temperature coefficient of each BGO crystal bar has been calibrated, and a correction method is also presented in this paper.
International Nuclear Information System (INIS)
The present study aims to investigate the dependences of ultrasonic properties on the propagation angle with respect to the trabecular alignment in 12 bovine femoral trabecular bone samples. The phase velocity and the attenuation coefficient of the fast wave measured at 0.5 MHz were found to decrease significantly with increasing angle and had their maximum values at 0 .deg. , i.e., for wave propagation in a direction parallel to the predominant trabecular alignment. The present study applied the angle-dependent Biot model by introducing anisotropy into the Biot model through the angle-dependent Young's, bulk, and shear moduli of the skeletal frame for trabecular bone to predict the measurements. Good agreement between the measurements and the prediction of the fast wave velocity suggests that the anisotropic fast wave velocity as a function of the propagation angle is mainly due to the variation in the elastic moduli of the skeletal frame with respect to the trabecular alignment.
An angle-dependent estimation of CT x-ray spectrum from rotational transmission measurements
Energy Technology Data Exchange (ETDEWEB)
Lin, Yuan, E-mail: yuan.lin@duke.edu; Samei, Ehsan [Carl E. Ravin Advanced Imaging Laboratories, Duke University Medical Center, Durham, North Carolina 27705 and Physics Department, Duke University, Durham, North Carolina 27708 (United States); Ramirez-Giraldo, Juan Carlos [Siemens Medical Solutions, Malvern, Pennsylvania 19355 (United States); Gauthier, Daniel J. [Physics Department, Duke University, Durham, North Carolina 27708 (United States); Stierstorfer, Karl [Siemens Healthcare, Forchheim 91301 (Germany)
2014-06-15
Purpose: Computed tomography (CT) performance as well as dose and image quality is directly affected by the x-ray spectrum. However, the current assessment approaches of the CT x-ray spectrum require costly measurement equipment and complicated operational procedures, and are often limited to the spectrum corresponding to the center of rotation. In order to address these limitations, the authors propose an angle-dependent estimation technique, where the incident spectra across a wide range of angular trajectories can be estimated accurately with only a single phantom and a single axial scan in the absence of the knowledge of the bowtie filter. Methods: The proposed technique uses a uniform cylindrical phantom, made of ultra-high-molecular-weight polyethylene and positioned in an off-centered geometry. The projection data acquired with an axial scan have a twofold purpose. First, they serve as a reflection of the transmission measurements across different angular trajectories. Second, they are used to reconstruct the cross sectional image of the phantom, which is then utilized to compute the intersection length of each transmission measurement. With each CT detector element recording a range of transmission measurements for a single angular trajectory, the spectrum is estimated for that trajectory. A data conditioning procedure is used to combine information from hundreds of collected transmission measurements to accelerate the estimation speed, to reduce noise, and to improve estimation stability. The proposed spectral estimation technique was validated experimentally using a clinical scanner (Somatom Definition Flash, Siemens Healthcare, Germany) with spectra provided by the manufacturer serving as the comparison standard. Results obtained with the proposed technique were compared against those obtained from a second conventional transmission measurement technique with two materials (i.e., Cu and Al). After validation, the proposed technique was applied to measure
An angle-dependent estimation of CT x-ray spectrum from rotational transmission measurements
International Nuclear Information System (INIS)
Purpose: Computed tomography (CT) performance as well as dose and image quality is directly affected by the x-ray spectrum. However, the current assessment approaches of the CT x-ray spectrum require costly measurement equipment and complicated operational procedures, and are often limited to the spectrum corresponding to the center of rotation. In order to address these limitations, the authors propose an angle-dependent estimation technique, where the incident spectra across a wide range of angular trajectories can be estimated accurately with only a single phantom and a single axial scan in the absence of the knowledge of the bowtie filter. Methods: The proposed technique uses a uniform cylindrical phantom, made of ultra-high-molecular-weight polyethylene and positioned in an off-centered geometry. The projection data acquired with an axial scan have a twofold purpose. First, they serve as a reflection of the transmission measurements across different angular trajectories. Second, they are used to reconstruct the cross sectional image of the phantom, which is then utilized to compute the intersection length of each transmission measurement. With each CT detector element recording a range of transmission measurements for a single angular trajectory, the spectrum is estimated for that trajectory. A data conditioning procedure is used to combine information from hundreds of collected transmission measurements to accelerate the estimation speed, to reduce noise, and to improve estimation stability. The proposed spectral estimation technique was validated experimentally using a clinical scanner (Somatom Definition Flash, Siemens Healthcare, Germany) with spectra provided by the manufacturer serving as the comparison standard. Results obtained with the proposed technique were compared against those obtained from a second conventional transmission measurement technique with two materials (i.e., Cu and Al). After validation, the proposed technique was applied to measure
Automatic correction scheme for the temperature dependent overlap function of CHM15k ceilometers
Haefele, Alexander; Poltera, Yann; Hervo, Maxime
2016-04-01
Imperfections in a lidar's overlap function lead to artefacts in the background, range and overlap corrected lidar signals. These artefacts can erroneously be interpreted as aerosol gradient or, in extreme cases, as cloud base leading to false cloud detection. A correct specification of the overlap function is hence crucial to use automatic elastic lidars (ceilometers) for the detection of the planetary boundary layer or low clouds. In this study an algorithm is presented to correct such artefacts. It is based on the assumption of a homogeneous boundary layer and a correct specification of the overlap function down to a minimum range, which must be situated within the boundary layer. The strength of the algorithm lies in a sophisticated quality check scheme which allows to reliably identify favorable atmospheric conditions. The algorithm has been applied to 2 years of data from a CHM15k ceilometer from Lufft. Backscatter signals corrected for background, range and overlap have been compared using the overlap function provided by the manufacturer and the one corrected with the presented algorithm. Differences between corrected and uncorrected signals reach up to 45% in the first 300m above ground. The amplitude of the correction turned out to be temperature dependent being larger for higher temperatures. A linear model of the correction as a function of the instrument's internal temperature has been derived from the experimental data. Case studies and a statistical analysis of the strongest gradient derived from corrected signals reveal that the temperature model is capable to correct overlap artefacts with high quality, in particular such due to diurnal variations. The presented correction method has the potential to significantly improve the detection of the boundary layer with gradient based methods because it removes false candidates and hence simplifies the attribution of the detected gradients to the planetary boundary layer. A particularly high benefit can be
Correction of a Depth-Dependent Lateral Distortion in 3D Super-Resolution Imaging.
Directory of Open Access Journals (Sweden)
Lina Carlini
Full Text Available Three-dimensional (3D localization-based super-resolution microscopy (SR requires correction of aberrations to accurately represent 3D structure. Here we show how a depth-dependent lateral shift in the apparent position of a fluorescent point source, which we term `wobble`, results in warped 3D SR images and provide a software tool to correct this distortion. This system-specific, lateral shift is typically > 80 nm across an axial range of ~ 1 μm. A theoretical analysis based on phase retrieval data from our microscope suggests that the wobble is caused by non-rotationally symmetric phase and amplitude aberrations in the microscope's pupil function. We then apply our correction to the bacterial cytoskeletal protein FtsZ in live bacteria and demonstrate that the corrected data more accurately represent the true shape of this vertically-oriented ring-like structure. We also include this correction method in a registration procedure for dual-color, 3D SR data and show that it improves target registration error (TRE at the axial limits over an imaging depth of 1 μm, yielding TRE values of < 20 nm. This work highlights the importance of correcting aberrations in 3D SR to achieve high fidelity between the measurements and the sample.
Verification of the MCNP (TM) Perturbation Correction Feature for Cross-Section Dependent Tallies
Energy Technology Data Exchange (ETDEWEB)
A. K. Hess; G. W. McKinney; J. S. Hendricks; L. L. Carter
1998-10-01
The Monte Carlo N-Particle Transport Code MCNP version 4B perturbation capability has been extended to cross-section dependent tallies and to the track-length estimate of Iqff in criticality problems. We present the complete theory of the MCNP perturbation capability including the correction to MCNP4B which enables cross-section dependent perturbation tallies. We also present the MCNP interface as an upgrade to the MCNP4B manual. Finally, we present test results demonstrating the validity of the perturbation capability in MCNP, particularly cross-section dependent problems.
Muskens, O.L.; Beek, van der T.; Lagendijk, A.
2011-01-01
The frequency correlations of light in complex photonic media are of interest as a tool for characterizing the dynamical aspects of light diffusion. We demonstrate here that the frequency correlation shows a pronounced angle dependence both in transmission and in reflection geometries. Using a broad
2002-01-01
The photo on the second page of the Bulletin n°48/2002, from 25 November 2002, illustrating the article «Spanish Visit to CERN» was published with a wrong caption. We would like to apologise for this mistake and so publish it again with the correct caption. The Spanish delegation, accompanied by Spanish scientists at CERN, also visited the LHC superconducting magnet test hall (photo). From left to right: Felix Rodriguez Mateos of CERN LHC Division, Josep Piqué i Camps, Spanish Minister of Science and Technology, César Dopazo, Director-General of CIEMAT (Spanish Research Centre for Energy, Environment and Technology), Juan Antonio Rubio, ETT Division Leader at CERN, Manuel Aguilar-Benitez, Spanish Delegate to Council, Manuel Delfino, IT Division Leader at CERN, and Gonzalo León, Secretary-General of Scientific Policy to the Minister.
Mikhailov, Eugeniy E.; Goda, Keisuke; Corbitt, Thomas; Mavalvala, Nergis
2005-01-01
We study the effects of frequency-dependent squeeze amplitude attenuation and squeeze angle rotation by electromagnetically induced transparency (EIT) on gravitational wave (GW) interferometers. We propose the use of low-pass, band-pass, and high-pass EIT filters, an S-shaped EIT filter, and an intra-cavity EIT filter to generate frequency-dependent squeezing for injection into the antisymmetric port of GW interferometers. We find that the EIT filters have several advantages over the previous...
Institute of Scientific and Technical Information of China (English)
李礼夫; 潘斌
2012-01-01
In order to improve the calculation accuracy of the angle of AFS, we integrate the kinematics property of vehicle to propose a correction model to improve the calculated result by the difference between values of the side slip angles of the front and rear wheels. And then,we establish a simulation model in the TESIS/veDYNA software to simulate and analyze. According to the simulation results,this method can correct the AFS angle by 17.21% to 29. 47%.%结合汽车的动力学特性,提出了利用前后车轮侧偏角之差来改善AFS转角计算精度的方法,建立了AFS转角修整模型,在此基础上,运用整车动力学仿真软件TESIS/veDYNA软件对该方法进行了仿真分析.仿真结果表明,该法对研究车型的AFS转角的修整率为17.21 ％～29.47％.
International Nuclear Information System (INIS)
The implantation of Cs atoms in silicon was investigated by dynamic computer simulations using the Monte-Carlo code T-DYN that takes into account the gradual change of the target composition due to the Cs irradiation. The incorporation of Cs atoms was studied for incidence angles ranging from 0 deg. to 85 deg. and for four impact energies (0.2, 0.5, 1 and 3 keV). The total implantation fluences were (1-2) x 1017 Cs/cm2, well above the values required to reach a stationary state. The steady-state Cs surface concentrations exhibit a pronounced dependence on impact angle and energy. At normal incidence, they vary between ∼0.57 (at 0.2 keV) and ∼0.18 (3 keV), but decrease with increasing incidence angle. Under equilibrium, the partial sputtering yield of Si exhibits the typical dependence on incidence angle, first increasing up to a maximum value (at ∼70 deg. - 75 deg.) and declining sharply for larger angles. For all irradiation conditions a strongly preferential sputtering of Cs as compared to Si atoms is found, increasing with decreasing irradiation energy (from 4.6 at 3 keV to 7.2 at 0.2 keV) and for nearer-normal incidence.
Energy Technology Data Exchange (ETDEWEB)
Gnaser, Hubert [Department of Physics, University of Kaiserslautern, D-67663 Kaiserslautern (Germany)], E-mail: gnaser@rhrk.uni-kl.de
2009-08-15
The implantation of Cs atoms in silicon was investigated by dynamic computer simulations using the Monte-Carlo code T-DYN that takes into account the gradual change of the target composition due to the Cs irradiation. The incorporation of Cs atoms was studied for incidence angles ranging from 0 deg. to 85 deg. and for four impact energies (0.2, 0.5, 1 and 3 keV). The total implantation fluences were (1-2) x 10{sup 17} Cs/cm{sup 2}, well above the values required to reach a stationary state. The steady-state Cs surface concentrations exhibit a pronounced dependence on impact angle and energy. At normal incidence, they vary between {approx}0.57 (at 0.2 keV) and {approx}0.18 (3 keV), but decrease with increasing incidence angle. Under equilibrium, the partial sputtering yield of Si exhibits the typical dependence on incidence angle, first increasing up to a maximum value (at {approx}70 deg. - 75 deg.) and declining sharply for larger angles. For all irradiation conditions a strongly preferential sputtering of Cs as compared to Si atoms is found, increasing with decreasing irradiation energy (from 4.6 at 3 keV to 7.2 at 0.2 keV) and for nearer-normal incidence.
López-Pascual, Juan; Cáceres, Magda Liliana; De Rosario, Helios; Page, Álvaro
2016-02-01
The reliability of joint rotation measurements is an issue of major interest, especially in clinical applications. The effect of instrumental errors and soft tissue artifacts on the variability of human motion measures is well known, but the influence of the representation of joint motion has not yet been studied. The aim of the study was to compare the within-subject reliability of three rotation formalisms for the calculation of the shoulder elevation joint angles. Five repetitions of humeral elevation in the scapular plane of 27 healthy subjects were recorded using a stereophotogrammetry system. The humerothoracic joint angles were calculated using the YX'Y" and XZ'Y" Euler angle sequences and the attitude vector. A within-subject repeatability study was performed for the three representations. ICC, SEM and CV were the indices used to estimate the error in the calculation of the angle amplitudes and the angular waveforms with each method. Excellent results were obtained in all representations for the main angle (elevation), but there were remarkable differences for axial rotation and plane of elevation. The YX'Y" sequence generally had the poorest reliability in the secondary angles. The XZ'Y' sequence proved to be the most reliable representation of axial rotation, whereas the attitude vector had the highest reliability in the plane of elevation. These results highlight the importance of selecting the method used to describe the joint motion when within-subjects reliability is an important issue of the experiment. This may be of particular importance when the secondary angles of motions are being studied. PMID:26787010
International Nuclear Information System (INIS)
The most commonly used methods of assessing the scoliotic deviation measure angles that are not clearly defined in relation to the anatomy of the patient. In order to give an anatomic basis for such measurements it is proposed to define the scoliotic deviation as the deviation the vertebral column makes with the sagittal plane. Both the Cobb and the Ferguson angles may be based on this definition. The present methods of measurement are then attempts to measure these angles. If the plane of these angles is parallel to the film, the measurement will be correct. Errors in the measurements may be incurred by the projection. A hypothetical projection, called a 'rectified orthogonal projection', is presented, which correctly represents all scoliotic angles in accordance with these principles. It can be constructed in practice with the aid of a computer and by performing measurements on two projections of the vertebral column; a scoliotic curve can be represented independent of the kyphosis and lordosis. (Auth.)
Correction to the MCNP trademark perturbation feature for cross-section dependent tallies
International Nuclear Information System (INIS)
The differential operator perturbation technique is a new feature of the Monte Carlo N-Particle Transport Code MCNP version 4B that will allow users to calculate the effects of cross-section data perturbations on tallies. The implementation of the differential operator perturbation technique in MCNP assumes that the tally is independent of any perturbed cross-section data, an assumption that may not be valid for some tallies. The authors provide derivations of both the first- and second-order corrected perturbations. In addition, the appropriate perturbation corrections are demonstrated so users may accurately calculate perturbation effects for any cross-section dependent tally. Finally, corrected perturbations from six example problems are compared to actual MCNP results
Angle-dependent magnetotransport in GaAs/InAs core/shell nanowires
Haas, Fabian; Wenz, Tobias; Zellekens, Patrick; Demarina, Nataliya; Rieger, Torsten; Lepsa, Mihail; Grützmacher, Detlev; Lüth, Hans; Schäpers, Thomas
2016-04-01
We study the impact of the direction of magnetic flux on the electron motion in GaAs/InAs core/shell nanowires. At small tilt angles, when the magnetic field is aligned nearly parallel to the nanowire axis, we observe Aharonov–Bohm type h/e flux periodic magnetoconductance oscillations. These are attributed to transport via angular momentum states, formed by electron waves within the InAs shell. With increasing tilt of the nanowire in the magnetic field, the flux periodic magnetoconductance oscillations disappear. Universal conductance fluctuations are observed for all tilt angles, however with increasing amplitudes for large tilt angles. We record this evolution of the electron propagation from a circling motion around the core to a diffusive transport through scattering loops and give explanations for the observed different transport regimes separated by the magnetic field orientation.
Komar, C M; Dorelli, J C; Glocer, A; Kuznetsova, M M
2013-01-01
A new, efficient, and highly accurate method for tracing magnetic separators in global magnetospheric simulations with arbitrary clock angle is presented. The technique is to begin at a magnetic null and iteratively march along the separator by finding where four magnetic topologies meet on a spherical surface. The technique is verified using exact solutions for separators resulting from an analytic magnetic field model that superposes dipolar and uniform magnetic fields. Global resistive magnetohydrodynamic simulations are performed using the three-dimensional BATS-R-US code with a uniform resistivity, in eight distinct simulations with interplanetary magnetic field (IMF) clock angles ranging from 0 (parallel) to 180 degrees (anti-parallel). Magnetic nulls and separators are found in the simulations, and it is shown that separators traced here are accurate for any clock angle, unlike the last closed field line on the Sun-Earth line that fails for southward IMF. Trends in magnetic null locations and the struc...
DEFF Research Database (Denmark)
Frederiksen, Thomas; Munuera, C.; Ocal, C.; Brandbyge, Mads; Paulsson, Magnus; Sanchez-Portal, D.; Arnau, A.
2009-01-01
Electronic transport mechanisms in molecular junctions are investigated by a combination of first-principles calculations and current−voltage measurements of several well-characterized structures. We study self-assembled layers of alkanethiols grown on Au(111) and form tunnel junctions by...... for the longer molecular chains. Our calculations confirm the observed trends and explain them as a result of two mechanisms, namely, a previously proposed intermolecular tunneling enhancement as well as a hitherto overlooked tilt-dependent molecular gate effect....... contacting the molecular layers with the tip of a conductive force microscope. Measurements done under low-load conditions permit us to obtain reliable tilt-angle and molecular length dependencies of the low-bias conductance through the alkanethiol layers. The observed dependence on tilt-angle is stronger...
1924-01-01
In experimenting with airfoil models in a wind tunnel, the magnitude of the forces acting on the model is affected by the fact that the air stream in which the model is suspended, has a restricted cross-section. In order to utilize the results for an airplane in an unlimited quantity of air, a correction must be made. The magnitude of this correction was determined by Prandtl by the application of his wing theory.
Impact of hadronic and nuclear corrections on global analysis of spin-dependent parton distributions
Energy Technology Data Exchange (ETDEWEB)
Jimenez-Delgado, Pedro [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Accardi, Alberto [Hampton University, Hampton, VA (United States); Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Melnitchouk, Wally [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States)
2014-02-01
We present the first results of a new global next-to-leading order analysis of spin-dependent parton distribution functions from the most recent world data on inclusive polarized deep-inelastic scattering, focusing in particular on the large-x and low-Q^2 regions. By directly fitting polarization asymmetries we eliminate biases introduced by using polarized structure function data extracted under nonuniform assumptions for the unpolarized structure functions. For analysis of the large-x data we implement nuclear smearing corrections for deuterium and 3He nuclei, and systematically include target mass and higher twist corrections to the g_1 and g_2 structure functions at low Q^2. We also explore the effects of Q^2 and W^2 cuts in the data sets, and the potential impact of future data on the behavior of the spin-dependent parton distributions at large x.
Temperature dependence calibration and correction of the DAMPE BGO electromagnetic calorimeter
Wei, Y. F.; Zhang, Z. Y.; Zhang, Y. L.; Wen, S. C.; Wang, C.; Li, Z. Y.; Feng, C. Q.; Wang, X. L.; Xu, Z. Z.; Huang, G. S.; Liu, S. B.
2016-07-01
A BGO electromagnetic calorimeter (ECAL) is built for the DArk Matter Particle Explorer (DAMPE) mission. The temperature effect on the BGO ECAL was investigated with a thermal vacuum experiment. The light output of a BGO crystal depends on temperature significantly, and the readout system is also affected by temperature. The temperature coefficient of each BGO detection unit has been calibrated, and a correction method is also presented in this paper.
Hashimoto, Yukio
2016-01-01
A numerical method to solve the TDHFB equations by using a hybrid basis of the two-dimensional harmonic oscillator eigenfunctions and one-dimensional Lagrange mesh with the Gogny effective interaction is applied to the head-on collisions of the superfluid nuclei ${}^{20}$O's. Taking the energies around the barrier top energy, the trajectories, pairing energies, and numbers of transferred nucleons are displayed. Their dependence on the relative gauge angle at the initial time is studied by taking typical sample points of the gauge angle. It turned out that the functional form of the flux of the neutrons across a section plane is proportional to the sine of the two times of the gauge angle.
Temperature dependent small-angle neutron scattering of CTABr-magnetic fluid emulsion
Indian Academy of Sciences (India)
V K Aswal; J V Joshi; P S Goyal; Rajesh Patel; R V Upadhyay; R V Mehta
2004-08-01
Small-angle neutron scattering studies have been carried out to check the structural integrity of citryltrimethylammonium bromide (CTABr) micelles in a magnetic fluid for different magnetic fluid concentrations at two different temperatures 303 and 333 K. It is found that the CTABr micelles grow with increasing magnetic fluid concentration and there is a decrease in the micellar size with increase in temperature.
Energy Technology Data Exchange (ETDEWEB)
Dooraghi, M.; Habte, A.; Reda, I.; Sengupta, M.; Gotseff, P.; Andreas, A.; Anderberg, M.
2014-03-01
This poster seeks to demonstrate the importance and application of an existing but unused approach that ultimately reduces the uncertainty of radiometric measurements. Current radiometric data is based on a single responsivity value that introduces significant uncertainty to the data, however, through using responsivity as a function of solar zenith angle, the uncertainty could be decreased by 50%.
Dossou, Kokou B
2015-01-01
Diffraction gratings are famous for their ability to exhibit, near a Wood anomaly, an arbitrarily large angular dispersion, e.g., with respect to the incidence angle or wavelength. For a diffraction grating under incidence by a plane wave at a fixed frequency, by rotating the incidence angle at a given angular velocity, the field propagated by a nonzero diffraction order will rotate at increasingly fast angular velocity as the incidence angle approaches the angle where Wood anomaly occurs. Such a fast rotating diffracted field has the potential to generate a substantial Doppler shift. Indeed, under the assumption of a grating with infinite extent, the expression for the instantaneous frequency shift perceived by an observer, who is looking into the light radiated by the diffraction order, is derived and it is in full agreement with the prediction from an interpretation based on the Doppler shift generated by a rotation of light sources. In particular the classical (non-relativistic) Doppler shift can take arb...
Apparent Contact Angle and Contact Angle Hysteresis on Liquid Infused Surfaces
Semprebon, Ciro; McHale, Glen; Kusumaatmaja, Halim
2016-01-01
We theoretically investigate the apparent contact angle and contact angle hysteresis of a droplet placed on a liquid infused surface. We show that the apparent contact angle is not uniquely defined by material parameters, but also has a strong dependence on the relative size between the droplet and its surrounding wetting ridge formed by the infusing liquid. We derive a closed form expression for the contact angle in the limit of vanishing wetting ridge, and compute the correction for small b...
Dykowski, Przemyslaw; Krynski, Jan
2015-04-01
The establishment of modern gravity control with the use of exclusively absolute method of gravity determination has significant advantages as compared to the one established mostly with relative gravity measurements (e.g. accuracy, time efficiency). The newly modernized gravity control in Poland consists of 28 fundamental stations (laboratory) and 168 base stations (PBOG14 - located in the field). Gravity at the fundamental stations was surveyed with the FG5-230 gravimeter of the Warsaw University of Technology, and at the base stations - with the A10-020 gravimeter of the Institute of Geodesy and Cartography, Warsaw. This work concerns absolute gravity determinations at the base stations. Although free of common relative measurement errors (e.g. instrumental drift) and effects of network adjustment, absolute gravity determinations for the establishment of gravity control require advanced corrections due to time dependent factors, i.e. tidal and ocean loading corrections, atmospheric corrections and hydrological corrections that were not taken into account when establishing the previous gravity control in Poland. Currently available services and software allow to determine high accuracy and high temporal resolution corrections for atmospheric (based on digital weather models, e.g. ECMWF) and hydrological (based on hydrological models, e.g. GLDAS/Noah) gravitational and loading effects. These corrections are mostly used for processing observations with Superconducting Gravimeters in the Global Geodynamics Project. For the area of Poland the atmospheric correction based on weather models can differ from standard atmospheric correction by even ±2 µGal. The hydrological model shows the annual variability of ±8 µGal. In addition the standard tidal correction may differ from the one obtained from the local tidal model (based on tidal observations). Such difference at Borowa Gora Observatory reaches the level of ±1.5 µGal. Overall the sum of atmospheric and
A deep-seated mechanism for cycle-dependent sunspot group tilt angles
Isik, Emre
2016-07-01
The cycle-averaged tilt angle of sunspot groups is an important quantity in determining the magnetic flux diffusing across the equator, which is highly correlated with the strength of the next cycle. This quantity has recently been reported to be anti-correlated with the strength of the solar cycle. I suggest that a deep-seated thermodynamic cycle can be responsible for the observed correlation. Motivated by helioseismic indications, I calculate the effect of cooling of the convective overshoot region on the stability and dynamics of thin, unstable flux tubes. I find that only 5-20 K of cooling in the layer can explain the observed range of tilt angle fluctuations among different cycles. This mechanism can play a role in the nonlinear saturation and amplitude fluctuations of the solar dynamo.
Moustapha Sané
2014-01-01
The aim of this work is to investigate a theoretical study of a vertical junction silicon solar cell capacitance under monochromatic illumination. By solving the continuity equation and using a one dimensional model in frequency modulation, we derive the analytical expressions of both excess minority carrier density and photovoltage. Based on these expressions, the solar cell capacitance was calculated; we then exhibited the effects of both temperature and incidence angle on the solar cell ca...
Nuclear Dependence in Weak Structure Functions and the Determination of Weak Mixing Angle
Athar, M Sajjad; Simo, I Ruiz; Vacas, M J Vicente
2013-01-01
We have studied nuclear medium effects in the weak structure functions $F^A_2(x)$ and $F^A_3(x)$ and in the extraction of weak mixing angle using Paschos Wolfenstein(PW) relation. We have modified the PW relation for nonisoscalar nuclear target. We have incorporated the medium effects like Pauli blocking, Fermi motion, nuclear binding energy, nucleon correlations, pion $\\&$ rho cloud contributions, and shadowing and antishadowing effects.
Mirica Karlovits
2014-01-01
Color-travel pigments, which exhibit much more extensive color change as well provide angle-dependent optical effect can be used in many industrial products. In present paper the multi-color effect pigment printed on three different foils with different background color (black, silver and transparent) was investigated. The pigment was based on synthetically produced transparent silicon dioxide platelets coated with titanium dioxide. CIEL*a*b* values and reflection of prints were measured by m...
Correcting direction-dependent gains in the deconvolution of radio interferometric images
Bhatnagar, S; Golap, K; Uson, Juan M
2008-01-01
Astronomical imaging using aperture synthesis telescopes requires deconvolution of the point spread function as well as calibration of instrumental and atmospheric effects. In general, such effects are time-variable and vary across the field of view as well, resulting in direction-dependent (DD), time-varying gains. Most existing imaging and calibration algorithms assume that the corruptions are direction independent, preventing even moderate dynamic range full-beam, full-Stokes imaging. We present a general framework for imaging algorithms which incorporate DD errors. We describe as well an iterative deconvolution algorithm that corrects known DD errors due to the antenna power patterns and pointing errors for high dynamic range full-beam polarimetric imaging. Using simulations we demonstrate that errors due to realistic primary beams as well as antenna pointing errors will limit the dynamic range of upcoming higher sensitivity instruments and that our new algorithm can be used to correct for such errors. We...
International Nuclear Information System (INIS)
We developed and validated a fast Monte Carlo simulation of PET acquisitions based on the SimSET program modeling accurately the propagation of gamma photons in the patient as well as the block-based PET detector. Comparison of our simulation with another well validated code, GATE, and measurements on two GE Discovery ST PET scanners showed that it models accurately energy spectra (errors smaller than 4.6%), the spatial resolution of block-based PET scanners (6.1%), scatter fraction (3.5%), sensitivity (2.3%) and count rates (12.7%). Next, we developed a novel scatter correction incorporating the energy and position of photons detected in list-mode. Our approach is based on the reformulation of the list-mode likelihood function containing the energy distribution of detected coincidences in addition to their spatial distribution, yielding an EM reconstruction algorithm containing spatial and energy dependent correction terms. We also proposed using the energy in addition to the position of gamma photons in the normalization of the scatter sinogram. Finally, we developed a method for estimating primary and scatter photons energy spectra from total spectra detected in different sectors of the PET scanner. We evaluated the accuracy and precision of our new spatio-spectral scatter correction and that of the standard spatial correction using realistic Monte Carlo simulations. These results showed that incorporating the energy in the scatter correction reduces bias in the estimation of the absolute activity level by ∼ 60% in the cold regions of the largest patients and yields quantification errors less than 13% in all regions. (author)
K. A. Mirzabekova
2015-01-01
Common pathogenic aspects of age-related macular degeneration (AMD) and primary open-angle glaucoma (POAG), i.e., the role of free radicals inducing oxidative damage of the retina and optic nerve, are discussed. Factors that activate free radical reactions as well as multilevel antioxidant protection system are reviewed. Data derived from studies on current antioxidants that are used to treat and prevent dry AMD and glaucomatous optic nerve damage are compared. Neuroprotection for glaucoma wi...
Characterizing time-dependent contact angles for sands hydrophobized with oleic and stearic acids
DEFF Research Database (Denmark)
Subedi, S; Kawamoto, K; Jayarathna, L;
2012-01-01
-frequency precipitation. A potential solution is to alter soil grain surfaces to become water repellent by mixing or coating the soil cover material with hydrophobic agents (HAs). In this study, hydrophobic CBs comprised of sands mixed with environmentally friendly HAs (oleic acid [OA] and stearic acid [SA]) were studied....... Water repellency (WR) characteristics for hydrophobized sand samples with different HA contents and representing different coating methods (mixing in and solvent aided) were measured. Initial contact angles (αi) for OA-coated samples sharply increased with increasing HA content and reached peak values...
Energy Technology Data Exchange (ETDEWEB)
Soda, Kazuo, E-mail: j45880a@cc.nagoya-u.ac.jp [Department of Quantum Engineering, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603 (Japan); Kondo, Hiroki; Yamaguchi, Kanta; Kato, Masahiko [Department of Quantum Engineering, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603 (Japan); Shiraki, Tatsuhito; Niwa, Ken; Kusaba, Keiji; Hasegawa, Masashi [Department of Crystalline Materials Science, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603 (Japan); Xeniya, Kozina; Ikenaga, Eiji [Japan Synchrotron Radiation Research Institute, 1-1-1, Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5198 (Japan)
2015-09-15
Highlights: • Nb hydrides in 10-GPa supercritical water are studied by photoelectron spectroscopy. • The hydride components of the Nb 3d core-level spectra are increased with the depth. • The bulk valence-band spectrum shows a split band due to the Nb–H bond formation. • The hydrides are formed in the bulk and their surfaces are covered with Nb oxides. - Abstract: Nb hydrides formation in 10-GPa supercritical water has been investigated by angle-dependent micro-beam hard X-ray photoemission spectroscopy. In the Nb 3d core-level spectra, Nb hydride components are found in the slightly high binding energy side of the metallic components, and the oxide ones are observed even though little oxides are recognized in X-ray diffraction patterns. Obtained emission-angle dependence of the Nb 3d core-level spectra of Nb hydride specimens shows that the Nb hydride components increase with the emission angle decreased i.e. the sampling depth increased, while the oxide ones decrease. The bulk valence-band spectrum is obtained by decomposing the measured valence-band spectra into a bulk and surface components with use of the emission-angle dependence of the core-level and valence-band spectra; it consists of two bands. This implies the Nb–H chemical bond formation and Nb in an oxidation state, consistent with reported band structure calculations and the observed core-level chemical shifts. Thus it is confirmed by valence-band and core-level photoelectron spectroscopy that the Nb hydrides are formed inside the specimen, irrespective to the well-known high oxidation ability of supercritical water.
International Nuclear Information System (INIS)
Purpose: Absorbed dose energy correction factors, used to convert the absorbed dose deposited in a LiF thermoluminescent dosimeter (TLD) into the clinically relevant absorbed dose to water, were obtained for both spherical volumetric sources and for the model 4140 HDR Yb-169 source. These correction factors have a strong energy dependence below 200 keV; therefore, spectral changes were quantified as Yb-169 photons traveled through both source material (Yb2O3) and water with the corresponding absorbed dose energy correction factors, f(r,θ), calculated as a function of location in a phantom. Methods: Using the MCNP5 Monte Carlo radiation transport simulation program, the Yb-169 spectrum emerging from spherical Yb2O3 sources (density 6.9 g/cm3) with radii between 0.2 and 0.9 mm were analyzed and their behavior compared against those for a point-source. The absorbed dose deposited to both LiF and H2O materials was analyzed at phantom depths of 0.1-10 cm for each source radius and the absorbed dose energy correction factor calculated as the ratio of the absorbed dose to water to that of LiF. Absorbed dose energy correction factors for the Model 4140 Yb-169 HDR brachytherapy source similarly were obtained and compared against those calculated for the Model M-19 Ir-192 HDR source. Results: The Yb-169 average spectral energy, emerging from Yb2O3 spherical sources 0.2-0.9 mm in radius, was observed to harden from 7% to 29%; as these photons traveled through the water phantom, the photon average energy softened by as much as 28% at a depth of 10 cm. Spectral softening was dependent on the measurement depth in the phantom. Energy correction factors were found to vary both as a function of source radius and phantom depth by as much as 10% for spherical Yb2O3 sources. The Model 4140 Yb-169 energy correction factors depended on both phantom depth and reference angle and were found to vary by more than 10% between depths of 1 and 10 cm and angles of 0 deg. and 180 deg. This was
Geng, Xu; Angal, Amit; Sun, Junqiang; Chen, Hongda; Wu, Aisheng; Li, Yonghong; Link, Daniel; Xiong, Xiaoxiong
2014-09-01
The MODerate resolution Imaging Spectroradiometer (MODIS) has 20 reflective solar bands (RSB), which are calibrated using a solar diffuser (SD) and near-monthly scheduled lunar observations via a space view (SV) port. The sensor responses observed at two different angles of incidence (AOI) from the SD and lunar measurements are used to track the on-orbit RSB gain changes as well as the response versus scan-angle (RVS) changes. The MODIS RSB have experienced wavelength dependent degradation since launch with the larger degradation observed at the shorter wavelengths. In addition to the SD and lunar observations, the MODIS Characterization Support Team (MCST) regularly monitors the response trending at multiple AOI over selected desert sites. In Collection 6 (C6), a new algorithm using the EV measurements from pseudoinvariant desert sites was developed to better characterize the MODIS scan-angle dependence and it led to a significant improvement in the long-term calibration consistency of the MODIS Level 1B (L1B) products. This approach is formulated for all RSB, and its application was recently extended to Terra band 10, leading to a significant improvement in the ocean-color products. This paper discusses the current status and performance of the on-orbit RVS characterization as applied in C6. Also, the various challenges and future improvement strategies associated with trending the EV response for the high-gain ocean bands are discussed.
Dong, Wan Jae; Lo, Nhat-Truong; Jung, Gwan Ho; Ham, Juyoung; Lee, Jong-Lam
2016-03-01
A distributed Bragg reflector (DBR) is conducted as a bottom reflector in see-through organic photovoltaics (OPVs) with an active layer of poly(3-hexylthiophene) and phenyl-C61-butyric acid methyl ester (P3HT:PCBM). The DBR consists of alternative layers of the high- and low-refractive index materials of Ta2O5 (n = 2.16) and SiO2 (n = 1.46). The DBR selectively reflects the light within a specific wavelength region (490 nm-630 nm) where the absorbance of P3HT:PCBM is maximum. The see-through OPVs fabricated on DBR exhibit efficiency enhancement by 31% compared to the device without DBR. Additionally, the angle-dependent transmittance of DBR is analysed using optical simulation and verified by experimental results. As the incident angle of light increases, peak of reflectance shifts to shorter wavelength and the bandwidth gets narrower. This unique angle-dependent optical properties of DBR allows the facile color change of see-through OPVs.
How important is self-consistency for the dDsC density dependent dispersion correction?
Energy Technology Data Exchange (ETDEWEB)
Brémond, Éric; Corminboeuf, Clémence, E-mail: clemence.corminboeuf@epfl.ch [Laboratory for Computational Molecular Design, Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne, CH-1015 Lausanne (Switzerland); Golubev, Nikolay [Laboratory for Computational Molecular Design, Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne, CH-1015 Lausanne (Switzerland); Department of Chemistry, M. V. Lomonosov Moscow State University, Moscow 119991 (Russian Federation); Steinmann, Stephan N., E-mail: sns25@duke.edu [Laboratory for Computational Molecular Design, Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne, CH-1015 Lausanne (Switzerland); Department of Chemistry, Duke University, Durham, North Carolina 27708 (United States)
2014-05-14
The treatment of dispersion interactions is ubiquitous but computationally demanding for seamless ab initio approaches. A highly popular and simple remedy consists in correcting for the missing interactions a posteriori by adding an attractive energy term summed over all atom pairs to standard density functional approximations. These corrections were originally based on atom pairwise parameters and, hence, had a strong touch of empiricism. To overcome such limitations, we recently proposed a robust system-dependent dispersion correction, dDsC, that is computed from the electron density and that provides a balanced description of both weak inter- and intramolecular interactions. From the theoretical point of view and for the sake of increasing reliability, we here verify if the self-consistent implementation of dDsC impacts ground-state properties such as interaction energies, electron density, dipole moments, geometries, and harmonic frequencies. In addition, we investigate the suitability of the a posteriori scheme for molecular dynamics simulations, for which the analysis of the energy conservation constitutes a challenging tests. Our study demonstrates that the post-SCF approach in an excellent approximation.
How important is self-consistency for the dDsC density dependent dispersion correction?
Brémond, Éric; Golubev, Nikolay; Steinmann, Stephan N; Corminboeuf, Clémence
2014-05-14
The treatment of dispersion interactions is ubiquitous but computationally demanding for seamless ab initio approaches. A highly popular and simple remedy consists in correcting for the missing interactions a posteriori by adding an attractive energy term summed over all atom pairs to standard density functional approximations. These corrections were originally based on atom pairwise parameters and, hence, had a strong touch of empiricism. To overcome such limitations, we recently proposed a robust system-dependent dispersion correction, dDsC, that is computed from the electron density and that provides a balanced description of both weak inter- and intramolecular interactions. From the theoretical point of view and for the sake of increasing reliability, we here verify if the self-consistent implementation of dDsC impacts ground-state properties such as interaction energies, electron density, dipole moments, geometries, and harmonic frequencies. In addition, we investigate the suitability of the a posteriori scheme for molecular dynamics simulations, for which the analysis of the energy conservation constitutes a challenging tests. Our study demonstrates that the post-SCF approach in an excellent approximation. PMID:24832324
How important is self-consistency for the dDsC density dependent dispersion correction?
International Nuclear Information System (INIS)
The treatment of dispersion interactions is ubiquitous but computationally demanding for seamless ab initio approaches. A highly popular and simple remedy consists in correcting for the missing interactions a posteriori by adding an attractive energy term summed over all atom pairs to standard density functional approximations. These corrections were originally based on atom pairwise parameters and, hence, had a strong touch of empiricism. To overcome such limitations, we recently proposed a robust system-dependent dispersion correction, dDsC, that is computed from the electron density and that provides a balanced description of both weak inter- and intramolecular interactions. From the theoretical point of view and for the sake of increasing reliability, we here verify if the self-consistent implementation of dDsC impacts ground-state properties such as interaction energies, electron density, dipole moments, geometries, and harmonic frequencies. In addition, we investigate the suitability of the a posteriori scheme for molecular dynamics simulations, for which the analysis of the energy conservation constitutes a challenging tests. Our study demonstrates that the post-SCF approach in an excellent approximation
Investigation of the zenith angle dependence of cosmic-ray muons at sea level
Indian Academy of Sciences (India)
Mehmet Bektasoglu; Halil Arslan
2013-05-01
Angular distribution of cosmic-ray muons at sea level has been investigated using the Geant4 simulation package. The model used in the simulations was tested by comparing the simulation results with the measurements made using the Berkeley Lab cosmic ray detector. Primary particles’ energy and fluxes were obtained from the experimental measurements. Simulations were run at each zenith angle starting from = 0° up to = 70° with 5° increment. The angular distribution of muons at sea level has been estimated to be in the form $I() = I(0^{°}) \\cos^{n}()$, where (0°) is the muon intensity at 0° and is a function of the muon momentum. The exponent = 1.95 ± 0.08 for muons with energies above 1 GeV is in good agreement, within error, with the values reported in the literature.
Prediction of the azimuth angle dependence of the quasimolecular anisotropy in heavy ion collisions
International Nuclear Information System (INIS)
Within the quasimolecular (MO) kinematic dipole model the authors predict a strong dependence of the anisotropy of the MO radiation on the orientation of the heavy ion scattering plane relative to the direction of the photon detection plane. (Auth.)
Yoo, Won-Gyu
2016-01-01
[Purpose] The purpose of this study was to investigate the effect of the difficulty level of a biofeedback device for postural correction on the orbicularis oculi and upper trapezius muscle activity and trunk flexion angle during computer work. [Subjects] Ten computer workers were included in this study. [Methods] The biofeedback tool used in this study provided visual and auditory feedback with regard to changes in trunk flexion angle under two different conditions during computer work: The first condition was when there was an increase of more than 10 degrees in a standard sitting posture. The second condition was when there was an increase of more than 20 degrees in the same posture. [Results] The trunk flexion angle showed no significant difference between conditions. The muscle activities of the orbicularis oculi and upper trapezius under condition 1 (high difficulty level) was significantly increased compared with those under condition 2 (low difficulty level). [Conclusion] This result showed that frequent feedback with greater sensitivity can trigger stress and lead to the outbreak of other illnesses. PMID:27065535
Chubykalo, O. A.; González, J.; Aragoneses, P.; Blanco, J. M.; Domínguez, L.; González, J. M.
1997-05-01
The small angle magnetization rotation (SAMR) method has been applied to the measurement of the torsional dependence of the saturation magnetostriction in a low-magnetostrictive amorphous Co-rich wire. The behaviour of the electric signal picked up from the sense coil has been investigated using experimental and numerical methods. The torsion introduces the first harmonic into the signal but the general formula for the measurement of the saturation magnetostriction remains valid. The conditions for the application of the method are discussed. The measurements of the saturation magnetostriction in the presence of an applied torsion have been carried out for as-quenched and annealed samples using different intensities of the annealing current. The magnetostriction coefficient, λs, depends linearly on the applied stress σ: λs = λs(0) + Aσ. The experimental dependence of the parameters λs(0) and A on the applied torsion and for different thermal treatments of the samples are also presented.
Directory of Open Access Journals (Sweden)
K. A. Mirzabekova
2015-01-01
Full Text Available Common pathogenic aspects of age-related macular degeneration (AMD and primary open-angle glaucoma (POAG, i.e., the role of free radicals inducing oxidative damage of the retina and optic nerve, are discussed. Factors that activate free radical reactions as well as multilevel antioxidant protection system are reviewed. Data derived from studies on current antioxidants that are used to treat and prevent dry AMD and glaucomatous optic nerve damage are compared. Neuroprotection for glaucoma will be considered soon as a basis for its treatment. B vitamins are generally included into therapeutic algorithms for glaucomatous optic neuropathy. While being metabolic therapeutics, they stimulate adaptive compensatory mechanisms and reduce the severity of various pathological processes, e.g., hypoxia, lipid peroxidation etc. Neurotrophic, antioxidant, and regenerative effects of B vitamins as wells as their involvement in metabolism, myelinsynthesis and other processes are of special importance for ophthalmologists. Currently, several vitamin and mineral supplements that differ in composition, dosage, and schedule are approved in Russia. SuperOptic, a biologically activeadditive, contains more free lutein (10 mg and zeaxanthin (500 μg as well as potent antioxidants (vitamin E and vitamin C, microelements (zinc and copper, and balanced vitamin B complex. These components play an important role in ocular health. SuperOptic can be recommended for the prevention and treatment of AMD and glaucomatous optic nerve damage.
International Nuclear Information System (INIS)
The dependence of the contact potential difference (CPD) reading on the ac driving amplitude in scanning Kelvin probe microscope (SKPM) hinders researchers from quantifying true material properties. We show theoretically and demonstrate experimentally that an ac driving amplitude dependence in the SKPM measurement can come from a systematic error, and it is common for all tip sample systems as long as there is a nonzero tracking error in the feedback control loop of the instrument. We further propose a methodology to detect and to correct the ac driving amplitude dependent systematic error in SKPM measurements. The true contact potential difference can be found by applying a linear regression to the measured CPD versus one over ac driving amplitude data. Two scenarios are studied: (a) when the surface being scanned by SKPM is not semiconducting and there is an ac driving amplitude dependent systematic error; (b) when a semiconductor surface is probed and asymmetric band bending occurs when the systematic error is present. Experiments are conducted using a commercial SKPM and CPD measurement results of two systems: platinum-iridium/gap/gold and platinum-iridium/gap/thermal oxide/silicon are discussed
A time dependent kinetic small angle neutron scattering study of a novel YFe phase
International Nuclear Information System (INIS)
Crystallization of amorphous Y67Fe33 into the YFe2 C15 Laves phase via a novel ‘YFe’ intermediate phase has been observed through to completion using time-resolved small angle neutron scattering (SANS). The nucleation and growth kinetics of the phase transformations have been studied at annealing temperatures below the crystallization temperatures for both the ‘YFe’ phase and the YFe2 phase. The SANS results agree with previously reported neutron diffraction and SANS data. At the annealing temperatures of 360, 370 and 380 ° C, changes in the scattering intensity I(Q) occur as a result of the contrast between the amorphous matrix and the nucleating and growing Y and ‘YFe’ phases. Critical scattering occurs during each of the isotherms, relating to the full crystallization of Y67Fe33, and extrapolation gives a crystallization temperature of 382 ° C. Beyond critical scattering, isotherms at 435, 450, and 465 ° C reveal the details of the continuing transformation of the ‘YFe’ intermediate phase into the YFe2 C15 Laves phase. (paper)
Pingali, Sai Venkatesh; O'Neill, Hugh M.; McGaughey, Joseph; Urban, Volker S.; Rempe, Caroline S.; Petridis, Loukas; Jeremy C Smith; Evans, Barbara R.; Heller, William T.
2011-01-01
Cellobiohydrolase I (Cel7A) of the fungus Trichoderma reesei (now classified as an anamorph of Hypocrea jecorina) hydrolyzes crystalline cellulose to soluble sugars, making it of key interest for producing fermentable sugars from biomass for biofuel production. The activity of the enzyme is pH-dependent, with its highest activity occurring at pH 4–5. To probe the response of the solution structure of Cel7A to changes in pH, we measured small angle neutron scattering of it in a series of solut...
Directory of Open Access Journals (Sweden)
Jyh Jian Chen
2014-03-01
Full Text Available Filling of liquid samples is realized in a microfluidic device with applications including analytical systems, biomedical devices, and systems for fundamental research. The filling of a disk-shaped polydimethylsiloxane (PDMS microchamber by liquid is analyzed with reference to microstructures with inlets and outlets. The microstructures are fabricated using a PDMS molding process with an SU-8 mold. During the filling, the motion of the gas-liquid interface is determined by the competition among inertia, adhesion, and surface tension. A single ramp model with velocity-dependent contact angles is implemented for the accurate calculation of surface tension forces in a three-dimensional volume-of-fluid based model. The effects of the parameters of this functional form are investigated. The influences of non-dimensional parameters, such as the Reynolds number and the Weber number, both determined by the inlet velocity, on the flow characteristics are also examined. An oxygen-plasma-treated PDMS substrate is utilized, and the microstructure is modified to be hydrophilic. Flow experiments are conducted into both hydrophilic and hydrophobic PDMS microstructures. Under a hydrophobic wall condition, numerical simulations with imposed boundary conditions of static and dynamic contact angles can successfully predict the moving of the meniscus compared with experimental measurements. However, for a hydrophilic wall, accurate agreement between numerical and experimental results is obvious as the dynamic contact angles were implemented.
Tsoukos, Athanasios; Bogdanis, Gregory C; Terzis, Gerasimos; Veligekas, Panagiotis
2016-08-01
Tsoukos, A, Bogdanis, GC, Terzis, G, and Veligekas, P. Acute improvement of vertical jump performance after isometric squats depends on knee angle and vertical jumping ability. J Strength Cond Res 30(8): 2250-2257, 2016-This study examined the acute effects of maximum isometric squats at 2 different knee angles (90 or 140°) on countermovement jump (CMJ) performance in power athletes. Fourteen national-level male track and field power athletes completed 3 main trials (2 experimental and 1 control) in a randomized and counterbalanced order 1 week apart. Countermovement jump performance was evaluated using a force-plate before and 15 seconds, 3, 6, 9, and 12 minutes after 3 sets of 3 seconds maximum isometric contractions with 1-minute rest in between, from a squat position with knee angle set at 90 or 140°. Countermovement jump performance was improved compared with baseline only in the 140° condition by 3.8 ± 1.2% on the 12th minute of recovery (p = 0.027), whereas there was no change in CMJ height in the 90° condition. In the control condition, there was a decrease in CMJ performance over time, reaching -3.6 ± 1.2% (p = 0.049) after 12 minutes of recovery. To determine the possible effects of baseline jump performance on subsequent CMJ performance, subjects were divided into 2 groups ("high jumpers" and "low jumpers"). The baseline CMJ values of "high jumpers" and "low jumpers" differed significantly (CMJ: 45.1 ± 2.2 vs. 37.1 ± 3.9 cm, respectively, p = 0.001). Countermovement jump was increased only in the "high jumpers" group by 5.4 ± 1.4% (p = 0.001) and 7.4 ± 1.2% (p = 0.001) at the knee angles of 90 and 140°, respectively. This improvement was larger at the 140° angle (p = 0.049). Knee angle during isometric squats and vertical jumping ability are important determinants of the acute CMJ performance increase observed after a conditioning activity. PMID:26808841
Correction of sound velocity depending on the temperature for unconsolidated marine sediment
Kim, Dae-Choul
2016-04-01
laboratory sound velocity measurements with systematic temperature change on unconsolidated marine sediment have been performed to establish the precise correction curves between temperature and the sound velocity. Piston and box core samples recovered from the East Sea and the South Sea of Korea were used for the measurement. The core samples were cooled (at temperature of nearly 0℃) and the temperature was gradually increased (from 0℃ to 30℃) to measure sound velocity depending on the changes in temperature. The sediment texture and physical properties (porosity, water content, and bulk density) were measured separately at the same depth. The rate of velocity increase for muddy, silty, and sandy sediment are about 2.63 m/s/℃, 2.74 m/s/℃, and 2.96 m/s/℃, respectively. This is similar to the velocity change rate, 2.97 m/s/℃ presented by Del Grosso (1952). The samples used in this research, however, have relatively higher porosity than those of Del Grosso (1952). Thus, the possibility of discrepancy is differences in water content which affect the sound velocity and measurement system. We used recently developed digital velocity measurement system using PXI based on LabVIEW. We suggest to employ this correction for the accurate in situ geoacoustic property from laboratory data particularly for the deep cold water sample such as the East Sea sediment that has very low bottom water temperature about 0℃. Keywords : in situ geoacoustic property, temperature correction, East Sea Acknowledgements: This research was supported by the Agency for Defense Development (UD14003DD) and by "Marine geological and geophysical mapping of the Korean seas" of the Korea Institute of Geoscience and Mineral Resources (KIGAM).
Energy Technology Data Exchange (ETDEWEB)
Shen, Z. X.
2011-08-15
The ({pi},{pi}) shadow band (SB) in La-based cuprate family (La214) was studied by angle-resolved photoemission spectroscopy (ARPES) over a wide doping range from x = 0.01 to x = 0.25. Unlike the well-studied case of the Bi-based cuprate family, an overall strong, monotonic doping dependence of the SB intensity at the Fermi level (E{sub F}) was observed. In contrast to a previous report for the presence of the SB only close to x = 1/8, we found it exists in a wide doping range, associated with a doping-independent ({pi},{pi}) wave vector but strongly doping-dependent intensity: It is the strongest at x {approx} 0.03 and systematically diminishes as the doping increases until it becomes negligible in the overdoped regime. This SB with the observed doping dependence of intensity can in principle be caused by the antiferromagnetic fluctuations or a particular form of low-temperature orthorhombic lattice distortion known to persist up to x {approx} 0.21 in the system, with both being weakened with increasing doping. However, a detailed binding energy dependent analysis of the SB at x = 0.07 does not appear to support the former interpretation, leaving the latter as a more plausible candidate, despite a challenge in quantitatively linking the doping dependences of the SB intensity and the magnitude of the lattice distortion. Our finding highlights the necessity of a careful and global consideration of the inherent structural complications for correctly understanding the cuprate Fermiology and its microscopic implication.
Boone, John M.
2009-01-01
Purpose: Dosimetry in computed tomography (CT) is increasingly based on Monte Carlo studies that define the dose in the patient (in mGy) as a function of air kerma (free in air) at isocenter (mGy). The accuracy of Monte Carlo studies depends in part on the accuracy of the characterization of the bow tie filter for a given CT scanner model. A simple method for characterizing the bow tie filter attenuation profile in CT scanners would therefore be very useful. The theory behind such a method is...
Wu, Dong L.; Gong, Jie
2011-01-01
Tropical anvil clouds play important roles in redistributing energy, water in the troposphere. Interacting with dynamics at a wide range of spatial and temporal scales, they can become organized internally and form structured cells, transporting momentum vertically and laterally. To quantify small-scale structures inside cirrus and anvils, we study view-dependence of the cloud-induced radiance from Atmospheric Infrared Sounder (AIRS) using channels near CO2 absorption line. The analysis of tropical eight-year (30degS-30degN, 2003-2010) data suggests that AIRS east-views observe 10% more anvil clouds than westviews during day (13:30 LST), whereas east-views and westviews observe equally amount of clouds at midnight (1 :30 LST). For entire tropical averages, AIRS oblique views observe more anvils than the nadir views, while the opposite is true for deep convective clouds. The dominance of cloudiness in the east-view cannot be explained by AIRS sampling and cloud microphysical differences. Tilted and banded anvil structures from convective scale to mesoscale are likely the cause of the observed view-dependent cloudiness, and gravity wave-cloud interaction is a plausible explanation for the observed structures. Effects of the tilted and banded cloud features need to be further evaluated and taken into account potentially in large-scale model parameterizations because of the vertical momentum transport through cloud wave breaking.
Djebbi, Ramzi
2013-08-19
Anisotropy is an inherent character of the Earth subsurface. It should be considered for modeling and inversion. The acoustic VTI wave equation approximates the wave behavior in anisotropic media, and especially it\\'s kinematic characteristics. To analyze which parts of the model would affect the traveltime for anisotropic traveltime inversion methods, especially for wave equation tomography (WET), we drive the sensitivity kernels for anisotropic media using the VTI acoustic wave equation. A Born scattering approximation is first derived using the Fourier domain acoustic wave equation as a function of perturbations in three anisotropy parameters. Using the instantaneous traveltime, which unwraps the phase, we compute the kernels. These kernels resemble those for isotropic media, with the η kernel directionally dependent. They also have a maximum sensitivity along the geometrical ray, which is more realistic compared to the cross-correlation based kernels. Focusing on diving waves, which is used more often, especially recently in waveform inversion, we show sensitivity kernels in anisotropic media for this case.
Comparison of Topographic Correction Methods
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Rudolf Richter
2009-07-01
Full Text Available A comparison of topographic correction methods is conducted for Landsat-5 TM, Landsat-7 ETM+, and SPOT-5 imagery from different geographic areas and seasons. Three successful and known methods are compared: the semi-empirical C correction, the Gamma correction depending on the incidence and exitance angles, and a modified Minnaert approach. In the majority of cases the modified Minnaert approach performed best, but no method is superior in all cases.
Strong spin-orbit coupling and Zeeman spin splitting in angle dependent magnetoresistance of Bi2Te3
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We have studied angle dependent magnetoresistance of Bi2Te3 thin film with field up to 9 T over 2–20 K temperatures. The perpendicular field magnetoresistance has been explained by the Hikami-Larkin-Nagaoka theory alone in a system with strong spin-orbit coupling, from which we have estimated the mean free path, the phase coherence length, and the spin-orbit relaxation time. We have obtained the out-of-plane spin-orbit relaxation time to be small and the in-plane spin-orbit relaxation time to be comparable to the momentum relaxation time. The estimation of these charge and spin transport parameters are useful for spintronics applications. For parallel field magnetoresistance, we have confirmed the presence of Zeeman effect which is otherwise suppressed in perpendicular field magnetoresistance due to strong spin-orbit coupling. The parallel field data have been explained using both the contributions from the Maekawa-Fukuyama localization theory for non-interacting electrons and Lee-Ramakrishnan theory of electron-electron interactions. The estimated Zeeman g-factor and the strength of Coulomb screening parameter agree well with the theory. Finally, the anisotropy in magnetoresistance with respect to angle has been described by the Hikami-Larkin-Nagaoka theory. This anisotropy can be used in anisotropic magnetic sensor applications.
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Robust indices of regional and global cardiac function are a key factor in detection and treatment of heart disease as well as understanding of the fundamental mechanisms of a healthy heart. Myocardial elastography provides a noninvasive method for imaging and measuring displacement and strain of the myocardium for the early detection of cardiovascular disease. However, two-dimensional in-plane axial and lateral strains measured depend on the sonographic view used. This becomes especially critical in a clinical setting and may induce large variations in the measured strains, potentially leading to false diagnoses. A novel method in myocardial elastography is proposed for eliminating this view dependence by deriving the polar, principal and classified principal strains. The performance of the proposed methodology is assessed by employing 3D finite-element left-ventricular models of a control and an ischemic canine heart. Although polar strains are angle-independent, they are sensitive to the selected reference coordinate system, which requires the definition of a centroid of the left ventricle (LV). In contrast, principal strains derived through eigenvalue decomposition exhibit the inherent characteristic of coordinate system independence, offering view (i.e., angle and centroid)-independent strain measurements. Classified principal strains are obtained by assigning the principal components in the physical ventricular coordinate system. An extensive strain analysis illustrates the improvement in interpretation and visualization of the full-field myocardial deformation by using the classified principal strains, clearly depicting the ischemic and non-ischemic regions. Strain maps, independent of sonographic views and imaging planes, that can be used to accurately detect regional contractile dysfunction are demonstrated
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Purpose: To evaluate the angular dependence correction for Matrix Evolution 2D array detector in quality assurance of volumetric modulated arc therapy(VMAT). Methods: Total ten patients comprising of different sites were planned for VMAT and taken for the study. Each plan was exposed on Matrix Evolution 2D array detector with Omnipro IMRT software based on the following three different methods using 6MV photon beams from Elekta Synergy linear accelerator. First method, VMAT plan was delivered on Matrix Evolution detector as it gantry mounted with dedicated holder with build-up of 2.3cm. Second, the VMAT plan was delivered with the static gantry angle on to the table mounted setup. Third, the VMAT plan was delivered with actual gantry angle on Matrix Evolution detector fixed in Multicube phantom with gantry angle sensor and angular dependence correction were applied to quantify the plan quality. For all these methods, the corresponding QA plans were generated in TPS and the dose verification was done for both point and 2D fluence analysis with pass criteria of 3% dose difference and 3mm distance to agreement. Results: The measured point dose variation for the first method was observed as 1.58±0.6% of mean and SD with TPS calculated. For second and third method, the mean and standard deviation(SD) was observed as 1.67±0.7% and 1.85±0.8% respectively. The 2D fluence analysis of measured and TPS calculated has the mean and SD of 97.9±1.1%, 97.88±1.2% and 97.55±1.3% for first, second and third methods respectively. The calculated two-tailed Pvalue for point dose and 2D fluence analysis shows the insignificance with values of 0.9316 and 0.9015 respectively, among the different methods of QA. Conclusion: The qualitative evaluation of angular dependence correction for Matrix Evolution 2D array detector shows its competency in accuracy of quality assurance measurement of composite dose distribution of volumetric modulated arc therapy
Foran, Philip S; Boxall, Colin; Denison, Kieth R
2012-12-21
Transparent TiO(2) thin films were prepared on quartz substrates via a reverse micelle, sol-gel, spin-coating technique. The time dependence of the TiO(2) film photoinduced superhydrophilicity (PISH) was measured by goniometric observation of the contact angle, θ, of sessile water drops at the film surfaces. In these measurements, the TiO(2) substrate was illuminated by 315 nm light and drops were sequentially applied at a range of illumination times. Using a model for the wetting of heterogeneous surfaces derived by Israelachvili and Gee, these measurements were used to calculate the time dependence of f(2), the fractional surface coverage of the TiO(2) surface by adventitious contaminating organics (Israelachvili, J. N.; Gee, M. L. Contact angles on chemically heterogeneous surfaces. Langmuir 1989, 5, 288). Extending this model to include a Langmuir-Hinshelwood based kinetic analysis of f(2) as a function of time allowed for calculation of an expected value for θ immediately prior to illumination, that is, at illumination time t = 0. Such expected values of θ at t = 0 were calculated using two possible values of θ(1), the contact angle on a pristine unilluminated homogeneous TiO(2) surface: (i) θ(1) = 4° as suggested by, inter alia, Zubkov et al. (Zubkov, T.; Stahl, D.; Thompson, T. L.; Panayotov, D.; Diwald, O.; Yates, J. T. Ultraviolet Light-Induced Hydrophilicity Effect on TiO(2)(110)(1 × 1). Dominant Role of the Photooxidation of Adsorbed Hydrocarbons Causing Wetting by Water Droplets. J. Phys. Chem. B2005, 109, 15454); and (ii) where θ(1) = 25°, as suggested by Fujishima et al., representative of a more hydrophobic homogeneous TiO(2) surface that reconstructs upon exposure to ultraband gap illumination into a hydrophilic surface where θ(1) → 0° (Fujishima, A.; Zhang, X.; Tryk, D. A. TiO(2) photocatalysis and related surface phenomena Surf. Sci. Rep.2008, 63, 515). Analysis of data from our experiments and from selected literature sources
Kim, In-Hoo; Józkowicz, Alicja; Piedra, Pedro A.; Oka, Kazuhiro; Chan, Lawrence
2001-01-01
Ideally, somatic gene therapy should result in lifetime reversal of genetic deficiencies. However, to date, phenotypic correction of monogenic hyperlipidemia in mouse models by in vivo gene therapy has been short-lived and associated with substantial toxicity. We have developed a helper-dependent adenoviral vector (HD-Ad) containing the apolipoprotein (apo) E gene. A single i.v. injection of this vector completely and stably corrected the hypercholesterolemia in apoE-deficient mice, an effect...
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P. Bobik
2013-01-01
Full Text Available The cosmic rays differential intensity inside the heliosphere, for energy below 30 GeV/nuc, depends on solar activity and interplanetary magnetic field polarity. This variation, termed solar modulation, is described using a 2D (radius and colatitude Monte Carlo approach for solving the Parker transport equation that includes diffusion, convection, magnetic drift, and adiabatic energy loss. Since the whole transport is strongly related to the interplanetary magnetic field (IMF structure, a better understanding of his description is needed in order to reproduce the cosmic rays intensity at the Earth, as well as outside the ecliptic plane. In this work an interplanetary magnetic field model including the standard description on ecliptic region and a polar correction is presented. This treatment of the IMF, implemented in the HelMod Monte Carlo code (version 2.0, was used to determine the effects on the differential intensity of Proton at 1 AU and allowed one to investigate how latitudinal gradients of proton intensities, observed in the inner heliosphere with the Ulysses spacecraft during 1995, can be affected by the modification of the IMF in the polar regions.
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We study the one-loop correction in Transverse-Momentum-Dependent(TMD) factorization for Drell-Yan processes at small transverse momentum of the lepton pair. We adopt the so-called subtractive approach, in which one can systematically construct contributions for subtracting long-distance effects represented by diagrams. The perturbative parts are obtained after the subtraction. We find that the perturbative coefficients of all structure functions in TMD factorization at leading twist are the same. The perturbative parts can also be studied with scattering of partons instead of hadrons. In this way, the factorization of many structure functions can only be examined by studying the scattering of multi-parton states, where there are many diagrams. These diagrams have no similarities to those treated in the subtractive approach. As an example, we use existing results of one structure function responsible for Single-Spin-Asymmetry, to show that these diagrams in the scattering of multi-parton states are equivalent to those treated in the subtractive approach after using Ward identity
Subclass problem-dependent design for error-correcting output codes.
Escalera, Sergio; Tax, David M J; Pujol, Oriol; Radeva, Petia; Duin, Robert P W
2008-06-01
A common way to model multi-class classification problems is by means of Error-Correcting Output Codes (ECOC). Given a multi-class problem, the ECOC technique designs a code word for each class, where each position of the code identifies the membership of the class for a given binary problem. A classification decision is obtained by assigning the label of the class with the closest code. One of the main requirements of the ECOC design is that the base classifier is capable of splitting each sub-group of classes from each binary problem. However, we can not guarantee that a linear classifier model convex regions. Furthermore, non-linear classifiers also fail to manage some type of surfaces. In this paper, we present a novel strategy to model multi-class classification problems using sub-class information in the ECOC framework. Complex problems are solved by splitting the original set of classes into sub-classes, and embedding the binary problems in a problem-dependent ECOC design. Experimental results show that the proposed splitting procedure yields a better performance when the class overlap or the distribution of the training objects conceil the decision boundaries for the base classifier. The results are even more significant when one has a sufficiently large training size. PMID:18421109
Kontar, E.P.; MacKinnon, A.L.; Schwartz, R. A.; Brown, J. C.
2006-01-01
The observed hard X-ray (HXR) flux spectrum I(ε) from solar flares is a combination of primary bremsstrahlung photons Ip(ε) with a spectrally modified component from photospheric Compton backscatter of downward primary emission. The latter can be significant, distorting or hiding the true features of the primary spectrum which are key diagnostics for acceleration and propagation of high energy electrons and of their energy budget. For the first time in solar physics, we use a Green'...
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Full text: Short-term environment dose-rate assessments using real-time digital dosimeters within a Nuclear Medicine Department (NMD) are gaining more world-wide uses recently. In the past, conventional ion chamber-type survey-meters are used dominantly in environmental dose rates evaluation. Although it has suffered less gamma energy-dependency, but it is less sensitive in comparison with other digital dosimeters and more bulky in design that can hardly make it into a pocket size application. With modern electronic advancement and its shrinking in physical size, real-time personal dosimeter nowadays has gaining more popular to use a miniature G-M counter or a solid-state diode sensor, or even a NaI(Tl) scintillation device for ambient radiation monitoring. Radiation sensor operated in pulse-mode can never been used in doses or dose rates determination since each digital pulse has carried no energy information of the impinging gamma ray being interactive with, especially in the G-M counter or the diode sensor case. The raw count rates measured from a pulse-mode device are heavily dependent on the packaging of the sensor to make it less energy-sensitive. The doses or dose rates are then calculated by using a built-in conversion factor, based on a Cs-137 beam source calibration data conducted by various manufacturing vendors, to convert its raw counts into a so-called dose or dose-rate unit. In this study, we have focused our interests in the low energy response of the digital dosimeters from several brands currently for our in-house uses. Mainly, Tc-99m and I-131 in point sources and water phantoms detection configurations have been deployed to simulate our NMD outpatients for environment radiation monitoring purpose. The energy-dependent correction factors of the digital dosimeters will be evaluated by using calibrated Tc-99m or I-131 standard sources directly that has much lower gamma energy than the Cs-137 beam source of 661 keV. In the near future, we would
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Purpose: The purpose of this study is to investigate the dose-volume variations of planning target volume (PTV) and organs-at-risk (OARs) in prostate volumetric modulated arc therapy (VMAT) when using different collimator angles. It is because collimator angle awareness is essential for planner to produce an optimal prostate VMAT plan in a rational time. Methods: Single-arc VMAT plans at different collimator angles (0o, 15o, 30o, 45o, 60o, 75o and 90o) were created systematically using a Harold heterogeneous pelvis phantom. For each change of collimator angle, a new plan was re-optimized for that angle. The prescription dose was 78 Gy per 39 fractions. Conformity index (CI), homogeneity index (HI), gradient index, machine monitor unit, dose-volume histogram, the mean and maximum doses of the PTV were calculated and analyzed. On the other hand, dose-volume histogram, the mean and maximum doses of the OARs such as bladder, rectum and femoral heads for different collimator angles were determined from the plans. Results: There was no significance difference, based on the plan dose-volume evaluation criteria, found in the VMAT optimizations for all studied collimator angles. Higher CI and lower HI were found for the 45o collimator angle. In addition, the 15o collimator angle provided lower HI similar to the 45o collimator angle. The 75o and 90o collimator angle were found good for the rectum sparing, and the 75o and 30o collimator angle were found good for the right and left femur sparing, respectively. The PTV dose coverage for each plan was comparatively independent of the collimator angle. Conclusion: The dosimetric results in this study are useful to the planner to select different collimator angles to improve the PTV coverage and OAR sparing in prostate VMAT
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Khan, M; Rehman, J; Khan, M [The Islaimia University of Bahawalpur, Bahawalpur, Punjab (Pakistan); Chow, J [Princess Margaret Cancer Center, Toronto, ON (Canada)
2014-06-01
Purpose: The purpose of this study is to investigate the dose-volume variations of planning target volume (PTV) and organs-at-risk (OARs) in prostate volumetric modulated arc therapy (VMAT) when using different collimator angles. It is because collimator angle awareness is essential for planner to produce an optimal prostate VMAT plan in a rational time. Methods: Single-arc VMAT plans at different collimator angles (0o, 15o, 30o, 45o, 60o, 75o and 90o) were created systematically using a Harold heterogeneous pelvis phantom. For each change of collimator angle, a new plan was re-optimized for that angle. The prescription dose was 78 Gy per 39 fractions. Conformity index (CI), homogeneity index (HI), gradient index, machine monitor unit, dose-volume histogram, the mean and maximum doses of the PTV were calculated and analyzed. On the other hand, dose-volume histogram, the mean and maximum doses of the OARs such as bladder, rectum and femoral heads for different collimator angles were determined from the plans. Results: There was no significance difference, based on the plan dose-volume evaluation criteria, found in the VMAT optimizations for all studied collimator angles. Higher CI and lower HI were found for the 45o collimator angle. In addition, the 15o collimator angle provided lower HI similar to the 45o collimator angle. The 75o and 90o collimator angle were found good for the rectum sparing, and the 75o and 30o collimator angle were found good for the right and left femur sparing, respectively. The PTV dose coverage for each plan was comparatively independent of the collimator angle. Conclusion: The dosimetric results in this study are useful to the planner to select different collimator angles to improve the PTV coverage and OAR sparing in prostate VMAT.
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This paper studies the fault detection process (FDP) and fault correction process (FCP) with the incorporation of testing effort function and imperfect debugging. In order to ensure high reliability, it is essential for software to undergo a testing phase, during which faults can be detected and corrected by debuggers. The testing resource allocation during this phase, which is usually depicted by the testing effort function, considerably influences not only the fault detection rate but also the time to correct a detected fault. In addition, testing is usually far from perfect such that new faults may be introduced. In this paper, we first show how to incorporate testing effort function and fault introduction into FDP and then develop FCP as delayed FDP with a correction effort. Various specific paired FDP and FCP models are obtained based on different assumptions of fault introduction and correction effort. An illustrative example is presented. The optimal release policy under different criteria is also discussed
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The surface chemical compositions, atomic concentration percentage and layer thickness after 'high-temperature' single-step activation and 'high-low temperature' two-step activation were obtained using quantitative analysis of angle-dependent X-ray photoelectron spectroscopy (XPS). It was found that compared to single-step activation, the thickness of GaAs-O interface barrier had a remarkable decrease, the degree of As-O bond became much smaller and the Ga-O bond became dominating, and at the same time the thickness of (Cs, O) layer also had a deduction while the ratio of Cs to O had no change after two-step activation. The measured spectral response curves showed that a increase of 29% of sensitivity had been obtained after two-step activation. To explore the inherent mechanisms of influences of the evolution of GaAs(Cs, O) surface layers on photoemission, surface electric barrier models based on the experimental results were built. By calculation of electron escape probability it was found that the decrease of thickness of GaAs-O interface barrier and (Cs, O) layer is the main reasons, which explained why higher sensitivity is achieved after two-step activation than single-step activation
The In-Plane Anisotropy of WTe2 Investigated by Angle-Dependent and Polarized Raman Spectroscopy.
Song, Qingjun; Pan, Xingchen; Wang, Haifeng; Zhang, Kun; Tan, Qinghai; Li, Pan; Wan, Yi; Wang, Yilun; Xu, Xiaolong; Lin, Miaoling; Wan, Xiangang; Song, Fengqi; Dai, Lun
2016-01-01
Tungsten ditelluride (WTe2) is a semi-metallic layered transition metal dichalcogenide with a stable distorted 1T phase. The reduced symmetry of this system leads to in-plane anisotropy in various materials properties. We have systemically studied the in-plane anisotropy of Raman modes in few-layer and bulk WTe2 by angle-dependent and polarized Raman spectroscopy (ADPRS). Ten Raman modes are clearly resolved. Their intensities show periodic variation with sample rotating. We identify the symmetries of the detected modes by quantitatively analyzing the ADPRS results based on the symmetry selection rules. Material absorption effect on the phonon modes with high vibration frequencies is investigated by considering complex Raman tensor elements. We also provide a rapid and nondestructive method to identify the crystallographic orientation of WTe2. The crystallographic orientation is further confirmed by the quantitative atomic-resolution force image. Finally, we find that the atomic vibrational tendency and complexity of detected modes are also reflected in the shrinkage degree defined based on ADPRS, which is confirmed by corresponding density functional calculation. Our work provides a deep understanding of the interaction between WTe2 and light, which will benefit in future studies about the anisotropic physical properties of WTe2 and other in-plane anisotropic materials. PMID:27404226
Time-dependent corrections to effective rate and event statistics in Michaelis-Menten kinetics
Sinitsyn, N. A.; Nemenman, I.
2010-01-01
We generalize the concept of the geometric phase in stochastic kinetics to a noncyclic evolution. Its application is demonstrated on kinetics of the Michaelis-Menten reaction. It is shown that the nonperiodic geometric phase is responsible for the correction to the Michaelis-Menten law when parameters, such as a substrate concentration, are changing with time. We apply these ideas to a model of chemical reactions in a bacterial culture of a growing size, where the geometric correction qualita...
Hervo, Maxime; Poltera, Yann; Haefele, Alexander
2016-07-01
Imperfections in a lidar's overlap function lead to artefacts in the background, range and overlap-corrected lidar signals. These artefacts can erroneously be interpreted as an aerosol gradient or, in extreme cases, as a cloud base leading to false cloud detection. A correct specification of the overlap function is hence crucial in the use of automatic elastic lidars (ceilometers) for the detection of the planetary boundary layer or of low cloud. In this study, an algorithm is presented to correct such artefacts. It is based on the assumption of a homogeneous boundary layer and a correct specification of the overlap function down to a minimum range, which must be situated within the boundary layer. The strength of the algorithm lies in a sophisticated quality-check scheme which allows the reliable identification of favourable atmospheric conditions. The algorithm was applied to 2 years of data from a CHM15k ceilometer from the company Lufft. Backscatter signals corrected for background, range and overlap were compared using the overlap function provided by the manufacturer and the one corrected with the presented algorithm. Differences between corrected and uncorrected signals reached up to 45 % in the first 300 m above ground. The amplitude of the correction turned out to be temperature dependent and was larger for higher temperatures. A linear model of the correction as a function of the instrument's internal temperature was derived from the experimental data. Case studies and a statistical analysis of the strongest gradient derived from corrected signals reveal that the temperature model is capable of a high-quality correction of overlap artefacts, in particular those due to diurnal variations. The presented correction method has the potential to significantly improve the detection of the boundary layer with gradient-based methods because it removes false candidates and hence simplifies the attribution of the detected gradients to the planetary boundary layer. A
Hamann, Jan; Hannestad, Steen; Melchiorri, Alessandro; Wong, Yvonne Y. Y.
2008-07-01
We explore and compare the performances of two non-linear correction and scale-dependent biasing models for the extraction of cosmological information from galaxy power spectrum data, especially in the context of beyond-ΛCDM (CDM: cold dark matter) cosmologies. The first model is the well known Q model, first applied in the analysis of Two-degree Field Galaxy Redshift Survey data. The second, the P model, is inspired by the halo model, in which non-linear evolution and scale-dependent biasing are encapsulated in a single non-Poisson shot noise term. We find that while the two models perform equally well in providing adequate correction for a range of galaxy clustering data in standard ΛCDM cosmology and in extensions with massive neutrinos, the Q model can give unphysical results in cosmologies containing a subdominant free-streaming dark matter whose temperature depends on the particle mass, e.g., relic thermal axions, unless a suitable prior is imposed on the correction parameter. This last case also exposes the danger of analytic marginalization, a technique sometimes used in the marginalization of nuisance parameters. In contrast, the P model suffers no undesirable effects, and is the recommended non-linear correction model also because of its physical transparency.
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We explore and compare the performances of two non-linear correction and scale-dependent biasing models for the extraction of cosmological information from galaxy power spectrum data, especially in the context of beyond-ΛCDM (CDM: cold dark matter) cosmologies. The first model is the well known Q model, first applied in the analysis of Two-degree Field Galaxy Redshift Survey data. The second, the P model, is inspired by the halo model, in which non-linear evolution and scale-dependent biasing are encapsulated in a single non-Poisson shot noise term. We find that while the two models perform equally well in providing adequate correction for a range of galaxy clustering data in standard ΛCDM cosmology and in extensions with massive neutrinos, the Q model can give unphysical results in cosmologies containing a subdominant free-streaming dark matter whose temperature depends on the particle mass, e.g., relic thermal axions, unless a suitable prior is imposed on the correction parameter. This last case also exposes the danger of analytic marginalization, a technique sometimes used in the marginalization of nuisance parameters. In contrast, the P model suffers no undesirable effects, and is the recommended non-linear correction model also because of its physical transparency
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Mathew, D; Tanny, S; Parsai, E; Sperling, N [University of Toledo Medical Center, Toledo, OH (United States)
2015-06-15
Purpose: The current small field dosimetry formalism utilizes quality correction factors to compensate for the difference in detector response relative to dose deposited in water. The correction factors are defined on a machine-specific basis for each beam quality and detector combination. Some research has suggested that the correction factors may only be weakly dependent on machine-to-machine variations, allowing for determinations of class-specific correction factors for various accelerator models. This research examines the differences in small field correction factors for three detectors across two Varian Truebeam accelerators to determine the correction factor dependence on machine-specific characteristics. Methods: Output factors were measured on two Varian Truebeam accelerators for equivalently tuned 6 MV and 6 FFF beams. Measurements were obtained using a commercial plastic scintillation detector (PSD), two ion chambers, and a diode detector. Measurements were made at a depth of 10 cm with an SSD of 100 cm for jaw-defined field sizes ranging from 3×3 cm{sup 2} to 0.6×0.6 cm{sup 2}, normalized to values at 5×5cm{sup 2}. Correction factors for each field on each machine were calculated as the ratio of the detector response to the PSD response. Percent change of correction factors for the chambers are presented relative to the primary machine. Results: The Exradin A26 demonstrates a difference of 9% for 6×6mm{sup 2} fields in both the 6FFF and 6MV beams. The A16 chamber demonstrates a 5%, and 3% difference in 6FFF and 6MV fields at the same field size respectively. The Edge diode exhibits less than 1.5% difference across both evaluated energies. Field sizes larger than 1.4×1.4cm2 demonstrated less than 1% difference for all detectors. Conclusion: Preliminary results suggest that class-specific correction may not be appropriate for micro-ionization chamber. For diode systems, the correction factor was substantially similar and may be useful for class
Optical advantages of astigmatic aberration corrected heliostats
van Rooyen, De Wet; Schöttl, Peter; Bern, Gregor; Heimsath, Anna; Nitz, Peter
2016-05-01
Astigmatic aberration corrected heliostats adapt their shape in dependence of the incidence angle of the sun on the heliostat. Simulations show that this optical correction leads to a higher concentration ratio at the target and thus in a decrease in required receiver aperture in particular for smaller heliostat fields.
Novel scatter compensation of list-mode PET data using spatial and energy dependent corrections
Guérin, Bastien; Fakhri, Georges El
2010-01-01
With the widespread use of PET crystals with greatly improved energy resolution (e.g., 11.5% with LYSO as compared to 20% with BGO) and of list-mode acquisitions, the use of the energy of individual events in scatter correction schemes becomes feasible. We propose a novel scatter approach that incorporates the energy of individual photons in the scatter correction and reconstruction of list-mode PET data in addition to the spatial information presently used in clinical scanners. First, we rew...
Kitamura, N.; Seki, K.; Keika, K.; Nishimura, Y.; Hori, T.; Strangeway, R. J.; Lund, E. J.
2014-12-01
Recent satellite observations and simulations have clarified that plasma outflows play an important role in abrupt changes in the ion composition in the plasmasheet and ring current during geomagnetic storms. Statistical studies by Strangeway et al. [2005] and Brambles et al. [2011] indicated that fluxes of ion outflows are correlated well with soft electron precipitation (precipitating electron density and electron density in the loss cone), and DC and Alfvenic Poynting fluxes using the data obtained by the FAST satellite near the cusp region in the dayside during the 24-25 September 1998 geomagnetic storm. To evaluate the correlations for H+ and O+ ions separately, we performed statistical studies using the ion composition data in addition to the ion, electron, and field data obtained by the FAST satellite during January 1998 and January 1999. The longer dataset enables us to identify empirical formulas between outflowing O+ and H+ ion fluxes and precipitating electron densities, DC and Alfvenic Poynting fluxes in a wide solar zenith angle (SZA) range (45°-145°). These empirical formulas would be useful for global magnetospheric simulations as the boundary conditions. Under dark conditions, H+ ion fluxes increases with increasing precipitating electron density, but not as much as those do under sunlit conditions. The precipitating electron density that corresponds to the H+ ion flux of ~107 /cm2/s （mapped to 1000 km altitude） decreases with increasing SZA. This SZA dependence is less clear for O+ ions as compared with H+ ions. The empirical formulas between outflowing O+ and H+ ion fluxes and DC and Alfvenic Poynting fluxes are not so strongly affected by SZA. Under sunlit conditions, the flux O+ ions tends to be larger than that of H+ ions, while H+ ions tend to become dominant under dark conditions. Intense ion (especially O+ ion) outflow events (>108 /cm2/s mapped to 1000 km altitude) mostly occurred under sunlit conditions or near the terminator.
Experimental validation of gallium production and isotope-dependent positron range correction in PET
Fraile, L. M.; Herraiz, J. L.; Udías, J. M.; Cal-González, J.; Corzo, P. M. G.; España, S.; Herranz, E.; Pérez-Liva, M.; Picado, E.; Vicente, E.; Muñoz-Martín, A.; Vaquero, J. J.
2016-04-01
Positron range (PR) is one of the important factors that limit the spatial resolution of positron emission tomography (PET) preclinical images. Its blurring effect can be corrected to a large extent if the appropriate method is used during the image reconstruction. Nevertheless, this correction requires an accurate modelling of the PR for the particular radionuclide and materials in the sample under study. In this work we investigate PET imaging with 68Ga and 66Ga radioisotopes, which have a large PR and are being used in many preclinical and clinical PET studies. We produced a 68Ga and 66Ga phantom on a natural zinc target through (p,n) reactions using the 9-MeV proton beam delivered by the 5-MV CMAM tandetron accelerator. The phantom was imaged in an ARGUS small animal PET/CT scanner and reconstructed with a fully 3D iterative algorithm, with and without PR corrections. The reconstructed images at different time frames show significant improvement in spatial resolution when the appropriate PR is applied for each frame, by taking into account the relative amount of each isotope in the sample. With these results we validate our previously proposed PR correction method for isotopes with large PR. Additionally, we explore the feasibility of PET imaging with 68Ga and 66Ga radioisotopes in proton therapy.
Corrected mean-field models for spatially dependent advection-diffusion-reaction phenomena
Simpson, Matthew J.; Baker, Ruth E.
2011-05-01
In the exclusion-process literature, mean-field models are often derived by assuming that the occupancy status of lattice sites is independent. Although this assumption is questionable, it is the foundation of many mean-field models. In this work we develop methods to relax the independence assumption for a range of discrete exclusion-process-based mechanisms motivated by applications from cell biology. Previous investigations that focused on relaxing the independence assumption have been limited to studying initially uniform populations and ignored any spatial variations. By ignoring spatial variations these previous studies were greatly simplified due to translational invariance of the lattice. These previous corrected mean-field models could not be applied to many important problems in cell biology such as invasion waves of cells that are characterized by moving fronts. Here we propose generalized methods that relax the independence assumption for spatially inhomogeneous problems, leading to corrected mean-field descriptions of a range of exclusion-process-based models that incorporate (i) unbiased motility, (ii) biased motility, and (iii) unbiased motility with agent birth and death processes. The corrected mean-field models derived here are applicable to spatially variable processes including invasion wave-type problems. We show that there can be large deviations between simulation data and traditional mean-field models based on invoking the independence assumption. Furthermore, we show that the corrected mean-field models give an improved match to the simulation data in all cases considered.
Pintore, F; di Salvo, T; Guainazzi, M; D'Aì, A; Riggio, A; Burderi, L; Iaria, R; Robba, N R
2014-01-01
When the EPIC-pn instrument on board XMM-Newton is operated in Timing mode, high count rates (>100 cts/s) of bright sources may affect the calibration of the energy scale, resulting in a modification of the real spectral shape. The corrections related to this effect are then strongly important in the study of the spectral properties. Tests of these calibrations are more suitable in sources which spectra are characterised by a large number of discrete features. Therefore, in this work, we carried out a spectral analysis of the accreting Neutron Star GX 13+1, which is a dipping source with several narrow absorption lines and a broad emission line in its spectrum. We tested two different correction approaches on an XMM-Newton EPIC-pn observation taken in Timing mode: the standard Rate Dependent CTI (RDCTI or epfast) and the new, Rate Dependent Pulse Height Amplitude (RDPHA) corrections. We found that, in general, the two corrections marginally affect the properties of the overall broadband continuum, while hints...
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Játékos, Balázs, E-mail: jatekosb@eik.bme.hu; Ujhelyi, Ferenc; Lőrincz, Emőke; Erdei, Gábor
2015-01-01
SPADnet-I is a prototype, fully digital, high spatial and temporal resolution silicon photon counter, based on standard CMOS imaging technology, developed by the SPADnet consortium. Being a novel device, the exact dependence of photon detection probability (PDP) of SPADnet-I was not known as a function of angle of incidence, wavelength and polarization of the incident light. Our targeted application area of this sensor is next generation PET detector modules, where they will be used along with LYSO:Ce scintillators. Hence, we performed an extended investigation of PDP in a wide range of angle of incidence (0° to 80°), concentrating onto a 60 nm broad wavelength interval around the characteristic emission peak (λ=420 nm) of the scintillator. In the case where the sensor was optically coupled to a scintillator, our experiments showed a notable dependence of PDP on angle, polarization and wavelength. The sensor has an average PDP of approximately 30% from 0° to 60° angle of incidence, where it starts to drop rapidly. The PDP turned out not to be polarization dependent below 30°. If the sensor is used without a scintillator (i.e. the light source is in air), the polarization dependence is much less expressed, it begins only from 50°.
International Nuclear Information System (INIS)
On the base of a data base on the rocket profiles of electron density, measured by means of an electrostatic probe, is precised an empirical dependence of the elecron density of the lower ionosphere on the Sun zenits angle for day-time middle-latitude (49 deg N, 44 deg E) heliogeophysically nondisturbed conditions
International Nuclear Information System (INIS)
SPADnet-I is a prototype, fully digital, high spatial and temporal resolution silicon photon counter, based on standard CMOS imaging technology, developed by the SPADnet consortium. Being a novel device, the exact dependence of photon detection probability (PDP) of SPADnet-I was not known as a function of angle of incidence, wavelength and polarization of the incident light. Our targeted application area of this sensor is next generation PET detector modules, where they will be used along with LYSO:Ce scintillators. Hence, we performed an extended investigation of PDP in a wide range of angle of incidence (0° to 80°), concentrating onto a 60 nm broad wavelength interval around the characteristic emission peak (λ=420 nm) of the scintillator. In the case where the sensor was optically coupled to a scintillator, our experiments showed a notable dependence of PDP on angle, polarization and wavelength. The sensor has an average PDP of approximately 30% from 0° to 60° angle of incidence, where it starts to drop rapidly. The PDP turned out not to be polarization dependent below 30°. If the sensor is used without a scintillator (i.e. the light source is in air), the polarization dependence is much less expressed, it begins only from 50°
Hamann, Jan; Melchiorri, Alessandro; Wong, Yvonne Y Y
2008-01-01
We explore and compare the performances of two nonlinear correction and scale-dependent biasing models for the extraction of cosmological information from galaxy power spectrum data, especially in the context of beyond-LCDM cosmologies. The first model is the well known Q model, first applied in the analysis of 2dFGRS data. The second, the P model, is inspired by the halo model, in which nonlinear evolution and scale-dependent biasing are encapsulated in a single non-Poisson shot noise term. We find that while both models perform equally well in providing adequate correction for a range of galaxy clustering data in standard LCDM cosmology and in extensions with massive neutrinos, the Q model can give unphysical results in cosmologies containing a subdominant free-streaming dark matter whose temperature depends on the particle mass, e.g., relic thermal axions, unless a suitable prior is imposed on the correction parameter. This last case also exposes the danger of analytic marginalisation, a technique sometime...
Directory of Open Access Journals (Sweden)
A. Gobiet
2015-06-01
Full Text Available This study discusses the effect of empirical-statistical bias correction methods like quantile mapping (QM on the change signals of climate simulations. We show that QM regionally alters the mean temperature climate change signal (CCS derived from the ENSEMBLES multi-model dataset by up to 15%. Such modification is currently strongly discussed and is often regarded as deficiency of bias correction methods. However, an analytical analysis reveals that this modification corresponds to the effect of intensity-dependent model errors on the CCS. Such errors cause, if uncorrected, biases in the CCS. QM removes these intensity-dependent errors and can therefore potentially lead to an improved CCS. A similar analysis as for the multi-model mean CCS has been conducted for the variance of CCSs in the multi-model ensemble. It shows that this indicator for model uncertainty is artificially inflated by intensity-dependent model errors. Therefore, QM has also the potential to serve as an empirical constraint on model uncertainty in climate projections. However, any improvement of simulated CCSs by empirical-statistical bias correction methods can only be realized, if the model error characteristics are sufficiently time-invariant.
Samer Medawar; Peter H\\xe4ndel; Niclas Bj\\xf6rsell; Magnus Jansson
2010-01-01
The integral nonlinearity (INL) is used for the postcorrection of analog-digital converters (ADCs). An input-frequency-dependent INL model is developed for the postcorrection. The model consists of a static term that is dependent on the ADC output code and a dynamic term that has an additional dependence on the input frequency. The concept of ADC digital output postcorrection by INL is first introduced. The INL model is subtracted from the digital output for postcorrection. The static compens...
International Nuclear Information System (INIS)
Angle- and energy-dependent cross sections for electron emission were measured for 68-MeV/u Kr33+ ions impacting on H2. These results show, in accordance with our earlier observation, that interference effects are produced by the coherent emission of electrons from the two H atoms, in analogy with Young's two-slit experiment. Furthermore, the present results demonstrate that the observed oscillatory pattern varies with the electron observation angle, contrary to our earlier expectations but in agreement with recent theoretical predictions
Renormalization scheme-dependence of perturbative quantum chromodynamics corrections to quarkonia
International Nuclear Information System (INIS)
QCD radiative corrections to physical quantities are studied using Stevenson's principle of minimal sensitivity (PMS) to define the renormalization. We examine several naive potentials (Cornell group, power law and logarithmic), as well as the more sophisticated Richardson model in order to determine the spectra for the non-relativistic heavy charmonium and bottomonium systems. Predictions are made for the values of hyperfine splittings, leptonic and hadronic decay widths and E1 transition rates for these families of mesons. It is shown that good agreement with experimental data may be achieved by using a constant value of Λ/sub QCD/, which is determined by the PMS scheme and the potential model
Dellambra, E; Vailly, J; Pellegrini, G; Bondanza, S; Golisano, O; Macchia, C; Zambruno, G; Meneguzzi, G; De Luca, M
1998-06-10
Laminin-5 is composed of three distinct polypeptides, alpha3, beta3, and gamma2, which are encoded by three different genes, LAMA3, LAMB3, and LAMC2, respectively. We have isolated epidermal keratinocytes from a patient presenting with a lethal form of junctional epidermolysis bullosa characterized by a homozygous mutation of the LAMB3 gene, which led to complete absence of the beta3 polypeptide. In vitro, beta3-null keratinocytes were unable to synthesize laminin-5 and to assemble hemidesmosomes, maintained the impairment of their adhesive properties, and displayed a decrease of their colony-forming ability. A retroviral construct expressing a human beta3 cDNA was used to transduce primary beta3-null keratinocytes. Clonogenic beta3-null keratinocytes were transduced with an efficiency of 100%. Beta3-transduced keratinocytes were able to synthesize and secrete mature heterotrimeric laminin-5. Gene correction fully restored the keratinocyte adhesion machinery, including the capacity of proper hemidesmosomal assembly, and prevented the loss of the colony-forming ability, suggesting a direct link between adhesion to laminin-5 and keratinocyte proliferative capacity. Clonal analysis demonstrated that holoclones expressed the transgene permanently, suggesting stable correction of epidermal stem cells. Because cultured keratinocytes are used routinely to make autologous grafts for patients suffering from large skin or mucosal defects, the full phenotypic reversion of primary human epidermal stem cells defective for a structural protein opens new perspectives in the long-term treatment of genodermatoses. PMID:9650620
Directory of Open Access Journals (Sweden)
Carmen Alexandru
2013-09-01
Full Text Available For a number N of elastomeric elements grouped in parallel, but mounted at an angle alpha between the compression axis and the vertical axis, the total stiffness should be assessed accordingly. The vibration transmissibility will be determined for two borderline cases, so that intermediate values can be evaluated for an anti-vibration isolation techniques solution
Energy Technology Data Exchange (ETDEWEB)
Nobile, E. [Univ. di Trieste (Italy)
1996-10-01
A time-accurate, additive-correction multigrid method for the prediction of two-dimensional unsteady flows is presented in this article. The method makes use of the additive-correction multigrid strategy, which, originally proposed for steady-flow problems, is extended to the calculation of time-dependent and chaotic flows at high Reynolds or Rayleigh numbers. The numerical algorithm guarantees absolute, to machine accuracy, mass conservation at every time step, and it is characterized by second-order accuracy in space and time. In a companion article, the method is applied to the calculation of unsteady flow in cavities, i.e., the lid-driven cavity problem at high Reynolds number, and the buoyant flow in differentially heated cavities at high values of the Rayleigh number. Although the method has been implemented and tested for two-dimensional flows, it can also be extended to three-dimensional problems.
Theoretical study of band gap in CuAlO2: Pressure dependence and self-interaction correction
International Nuclear Information System (INIS)
By using first-principles calculations, we studied the energy gaps of delafossite CuAlO2: (1) pressure dependence and (2) self-interaction correction (SIC). Our simulation shows that CuAlO2 transforms from a delafossite structure to a leaning delafossite structure at 60 GPa. The energy gap of CuAlO2 increases through the structural transition due to the enhanced covalency of Cu 3d and O 2p states. We implemented a self-interaction correction (SIC) into first-principles calculation code to go beyond local density approximation and applied it to CuAlO2. The energy gap calculated within the SIC is close to experimental data while one calculated without the SIC is about 1 eV smaller than the experimental data.
International Nuclear Information System (INIS)
The constraint of a progressive decrease in residual renormalization scale dependence with increasing loop order is developed as a method for obtaining bounds on unknown higher-order perturbative corrections to renormalization-group-invariant quantities. This technique is applied to the inclusive semileptonic process b→uν-barll- (explicitly known to two-loop order) in order to obtain bounds on the three- and four-loop perturbative contributions that are not accessible via the renormalization group. Combining this technique with the principle of minimal sensitivity, we obtain an estimate for the perturbative contributions to Γ (b→uν-barll-) that incorporates theoretical uncertainty from as-yet-undetermined higher-order QCD corrections. (Letter-to-the-editor)
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A methodology is presented whereby the relationship between temperature and emissivity for fused quartz has been used to correct the temperature values of a quartz impingement plate detected by an SC3000 thermal imaging camera. The methodology uses an iterative method using the initial temperature (obtained by assuming a constant emissivity) to find the emissivity values which are then put into the thermal imaging software and used to find the subsequent temperatures, which are used to find the emissivities, and so on until converged. This method is used for a quartz impingement plate that has been heated under various flame conditions, and the results are compared. Radiation losses from the plate are also calculated, and it is shown that even a slight change in temperature greatly affects the radiation loss. It is a general methodology that can be used for any wall material whose emissivity is a function of temperature
Li, Z. W.
2012-05-01
The propagation delay when radar signals travel from the troposphere has been one of the major limitations for the applications of high precision repeat-pass Interferometric Synthetic Aperture Radar (InSAR). In this paper, we first present an elevation-dependent atmospheric correction model for Advanced Synthetic Aperture Radar (ASAR—the instrument aboard the ENVISAT satellite) interferograms with Medium Resolution Imaging Spectrometer (MERIS) integrated water vapour (IWV) data. Then, using four ASAR interferometric pairs over Southern California as examples, we conduct the atmospheric correction experiments with cloud-free MERIS IWV data. The results show that after the correction the rms differences between InSAR and GPS have reduced by 69.6 per cent, 29 per cent, 31.8 per cent and 23.3 per cent, respectively for the four selected interferograms, with an average improvement of 38.4 per cent. Most importantly, after the correction, six distinct deformation areas have been identified, that is, Long Beach–Santa Ana Basin, Pomona–Ontario, San Bernardino and Elsinore basin, with the deformation velocities along the radar line-of-sight (LOS) direction ranging from −20 mm yr−1 to −30 mm yr−1 and on average around −25 mm yr−1, and Santa Fe Springs and Wilmington, with a slightly low deformation rate of about −10 mm yr−1 along LOS. Finally, through the method of stacking, we generate a mean deformation velocity map of Los Angeles over a period of 5 yr. The deformation is quite consistent with the historical deformation of the area. Thus, using the cloud-free MERIS IWV data correcting synchronized ASAR interferograms can significantly reduce the atmospheric effects in the interferograms and further better capture the ground deformation and other geophysical signals.
2010-06-08
... Register on September 30, 1997, at 62 FR 51274, amending 38 CFR 3.503, by redesignating paragraphs (a... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF VETERANS AFFAIRS 38 CFR Part 21 Nonduplication; Pension, Compensation, and Dependency and Indemnity...
Robust and bias-corrected estimation of the coefficient of tail dependence
DEFF Research Database (Denmark)
Dutang, C.; Goegebeur, Y.; Guillou, A.
2014-01-01
We introduce a robust and asymptotically unbiased estimator for the coefficient of tail dependence in multivariate extreme value statistics. The estimator is obtained by fitting a second order model to the data by means of the minimum density power divergence criterion. The asymptotic properties ...... the estimator are investigated. The efficiency of our methodology is illustrated on a small simulation study and by a real dataset from the actuarial context. (C) 2014 Elsevier B.V. All rights reserved....
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Purpose: Many cell irradiation experiments with low-energy laser-driven ions rely on radiochromic films (RCF), because of their dose-rate independent response and superior spatial resolution. RCF dosimetry in low-energy ion beams requires a correction of the LET dependent film response. The relative efficiency (RE), the ratio of photon to proton dose that yields the same film darkening, is a measure for the film’s LET dependence. A direct way of RE determination is RCF irradiation with low-energy mono-energetic protons and hence, well-defined LET. However, RE is usually determined using high energy proton depth dose measurements where RE corrections require knowledge of the average LET in each depth, which can be either track (tLET) or dose (dLET) averaged. The appropriate LET concept has to be applied to allow a proper film response correction. Methods: Radiochromic EBT2 and EBT3 films were irradiated in clinical photon and proton beams. For each depth of the 200 MeV proton depth dose curve, tLET and dLET were calculated by special user routines from the Monte Carlo code FLUKA. Additional irradiations with mono-energetic low energy protons (4–20 MeV) serve as reference for the RE determination. Results: The difference of dLET and tLET increases with depth, with the dLET being almost twice as large as the tLET for the maximum depth. The comparison with mono-energetic measurements shows a good agreement of the RE for the dLET concept, while a considerably steeper drop in RE is observed when applying the tLET. Conclusion: RCF can be used as reference dosimeter for biomedical experiments with low-energy proton beams if appropriate LET corrections are applied. When using depth dose measurements from clinical proton accelerators for these corrections, the concept of dLET has to be applied. Acknowledgement: This work was funded by the DFG Cluster of Excellence ‘Munich-Centre for Advanced Photonics’ (MAP). This work was funded by the DFG Cluster of Excellence
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Reinhardt, S; Wuerl, M; Assmann, W; Parodi, K [Department of Medical Physics, Ludwig-Maximilians University Munich, Garching, DE (Germany); Greubel, C [Institut fuer Angewandte Physik und Messtechnik (LRT2), Universitaet der Bundeswehr, Neubiberg, DE (United States); Wilkens, J [Department of Radiation Oncology, Technical University Munich, Klinikum rechts der Isar, Munich, DE (Germany); Hillbrand, M [Rinecker Proton Therapy Center, Munich, DE (Germany); Mairani, A [Medical Physics Unit CNAO Foundation, Pavia (Italy)
2015-06-15
Purpose: Many cell irradiation experiments with low-energy laser-driven ions rely on radiochromic films (RCF), because of their dose-rate independent response and superior spatial resolution. RCF dosimetry in low-energy ion beams requires a correction of the LET dependent film response. The relative efficiency (RE), the ratio of photon to proton dose that yields the same film darkening, is a measure for the film’s LET dependence. A direct way of RE determination is RCF irradiation with low-energy mono-energetic protons and hence, well-defined LET. However, RE is usually determined using high energy proton depth dose measurements where RE corrections require knowledge of the average LET in each depth, which can be either track (tLET) or dose (dLET) averaged. The appropriate LET concept has to be applied to allow a proper film response correction. Methods: Radiochromic EBT2 and EBT3 films were irradiated in clinical photon and proton beams. For each depth of the 200 MeV proton depth dose curve, tLET and dLET were calculated by special user routines from the Monte Carlo code FLUKA. Additional irradiations with mono-energetic low energy protons (4–20 MeV) serve as reference for the RE determination. Results: The difference of dLET and tLET increases with depth, with the dLET being almost twice as large as the tLET for the maximum depth. The comparison with mono-energetic measurements shows a good agreement of the RE for the dLET concept, while a considerably steeper drop in RE is observed when applying the tLET. Conclusion: RCF can be used as reference dosimeter for biomedical experiments with low-energy proton beams if appropriate LET corrections are applied. When using depth dose measurements from clinical proton accelerators for these corrections, the concept of dLET has to be applied. Acknowledgement: This work was funded by the DFG Cluster of Excellence ‘Munich-Centre for Advanced Photonics’ (MAP). This work was funded by the DFG Cluster of Excellence
International Nuclear Information System (INIS)
Highlights: ► Multiphoton ionization is calculated by time-dependent density functional theory. ►Exchange-correlation potential is built by time-dependent Krieger-Li-Iafrate method. ► Integer discontinuity of the potential improves description of ionization. ► Probabilities of single ionization of Li and double ionization of Be are presented. - Abstract: In the framework of the time-dependent density functional theory, we have performed 3D calculations of multiphoton ionization of Li and Be atoms by strong near-infrared laser fields. The results for the intensity-dependent probabilities of single and double ionization are presented. We make use of the time-dependent Krieger-Li-Iafrate exchange-correlation potential with self-interaction correction (TD-KLI-SIC). Such a potential possesses an integer discontinuity which improves description of the ionization process. However, we have found that the discontinuity of the TD-KLI-SIC potential is not sufficient to reproduce characteristic feature of double ionization.
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Ablation rate dependence on laser fluence for copper subjected to oblique femtosecond laser irradiation has been determined experimentally in order to investigate processing induced by oblique irradiation. A difference of ablation rate between p-polarized and s-polarized oblique irradiation is clearly observed. Effective penetration depth is defined to explain the ablation rate dependence instead of using optical penetration depth, which is treated as a key value for determining the ablation rate in conventional theory. The effective penetration depth for copper is presented in simple formulas as a function of laser incidence angle for each polarization
Scarino, B. R.; Minnis, P.; Yost, C. R.; Chee, T.; Palikonda, R.
2015-12-01
Single-channel algorithms for satellite thermal-infrared- (TIR-) derived land and sea surface skin temperature (LST and SST) are advantageous in that they can be easily applied to a variety of satellite sensors. They can also accommodate decade-spanning instrument series, particularly for periods when split-window capabilities are not available. However, the benefit of one unified retrieval methodology for all sensors comes at the cost of critical sensitivity to surface emissivity (ɛs) and atmospheric transmittance estimation. It has been demonstrated that as little as 0.01 variance in ɛs can amount to more than a 0.5-K adjustment in retrieved LST values. Atmospheric transmittance requires calculations that employ vertical profiles of temperature and humidity from numerical weather prediction (NWP) models. Selection of a given NWP model can significantly affect LST and SST agreement relative to their respective validation sources. Thus, it is necessary to understand the accuracies of the retrievals for various NWP models to ensure the best LST/SST retrievals. The sensitivities of the single-channel retrievals to surface emittance and NWP profiles are investigated using NASA Langley historic land and ocean clear-sky skin temperature (Ts) values derived from high-resolution 11-μm TIR brightness temperature measured from geostationary satellites (GEOSat) and Advanced Very High Resolution Radiometers (AVHRR). It is shown that mean GEOSat-derived, anisotropy-corrected LST can vary by up to ±0.8 K depending on whether CERES or MODIS ɛs sources are used. Furthermore, the use of either NOAA Global Forecast System (GFS) or NASA Goddard Modern-Era Retrospective Analysis for Research and Applications (MERRA) for the radiative transfer model initial atmospheric state can account for more than 0.5-K variation in mean Ts. The results are compared to measurements from the Surface Radiation Budget Network (SURFRAD), an Atmospheric Radiation Measurement (ARM) Program ground
International Nuclear Information System (INIS)
The purpose of the study was to create detector element-specific angular correction factors for each detector of the MatriXX planar ion chamber array and compare them to vendor-default angular correction factors. Additionally, the impact of both factors on gamma index was quantified using two corrections. The correction factor of each element is determined irradiating the detector at different incidences by the ratio of the calculated expected dose to the MatriXX measured dose as a gantry angle function. To evaluate its impact, sixty-five pre-irradiated patient-specific dose validations were re-analyzed using the gamma index with: 3%/3 mm, 2%/2 mm, 1%/1 mm criteria. The factors for 6 MV were found to differ (7%) from the default ones for specific angles particularly for 85 degree centigrade to 95 degree centigrade. For 10 MV, differences (1.0%) existed when correction factors were created using various ROI's. Two corrections were proposed, absolute differences for 3%/3 mm, 2%/2 mm, and 1%/1 mm were up to 1.5%, 4.2% and 4.1% ( p < 0.01), respectively. Large differences in the default and specific factors were noted for 6 MV and lead to improvement of the absolute gamma index value of up to 4.2%. In general, gamma index value increases for patient specific dose validations when using device specific factors. (Author)
Hammermann, M; Brun, N; Klenin, K V; May, R.; Tóth, K; Langowski, J.
1998-01-01
Using small angle neutron scattering we have measured the static form factor of two different superhelical DNAs, p1868 (1868 bp) and pUC18 (2686 bp), in dilute aqueous solution at salt concentrations between 0 and 1.5 M Na+ in 10 mM Tris at 0% and 100% D2O. For both DNA molecules, the theoretical static form factor was also calculated from an ensemble of Monte Carlo configurations generated by a previously described model. Simulated and measured form factors of both DNAs showed the same behav...
International Nuclear Information System (INIS)
Compared to conventional ferrofluids, which contain mostly spherical particles, a dispersion of highly anisometric particles such as rods or chains is expected to give rise to an enhancement or modification of well-known ferrofluid properties. This contribution reports on the synthesis of a ferrofluid containing stable chains of iron nanoparticles and on its microstructural characterisation by means of transmission electron microscopy and small-angle X-ray scattering (SAXS). The SAXS measurements develop a pronounced anisotropy of the scattering pattern as a function of an increasing external magnetic field. Evaluation of the radially averaged SAXS curves in terms of basic scattering functions is discussed
Energy Technology Data Exchange (ETDEWEB)
Doebrich, F. [Universitaet des Saarlandes, Technische Physik, Geb. D2 2, 66041 Saarbruecken (Germany)]. E-mail: f.doebrich@nano.uni-saarland.de; Michels, A. [Universitaet des Saarlandes, Technische Physik, Geb. D2 2, 66041 Saarbruecken (Germany); Birringer, R. [Universitaet des Saarlandes, Technische Physik, Geb. D2 2, 66041 Saarbruecken (Germany)
2007-09-15
Compared to conventional ferrofluids, which contain mostly spherical particles, a dispersion of highly anisometric particles such as rods or chains is expected to give rise to an enhancement or modification of well-known ferrofluid properties. This contribution reports on the synthesis of a ferrofluid containing stable chains of iron nanoparticles and on its microstructural characterisation by means of transmission electron microscopy and small-angle X-ray scattering (SAXS). The SAXS measurements develop a pronounced anisotropy of the scattering pattern as a function of an increasing external magnetic field. Evaluation of the radially averaged SAXS curves in terms of basic scattering functions is discussed.
Energy Technology Data Exchange (ETDEWEB)
Palmans, H. [Ghent Univ. (Belgium). Dept. of Biomedical Physics; Verhaegen, F.
1995-12-01
In the last decade, several clinical proton beam therapy facilities have been developed. To satisfy the demand for uniformity in clinical (routine) proton beam dosimetry two dosimetry protocols (ECHED and AAPM) have been published. Both protocols neglect the influence of ion chamber dependent parameters on dose determination in proton beams because of the scatter properties of these beams, although the problem has not been studied thoroughly yet. A comparison between water calorimetry and ionisation chamber dosimetry showed a discrepancy of 2.6% between the former method and ionometry following the ECHED protocol. Possibly, a small part of this difference can be attributed to chamber dependent correction factors. Indications for this possibility are found in ionometry measurements. To allow the simulation of complex geometries with different media necessary for the study of those corrections, an existing proton Monte Carlo code (PTRAN, Berger) has been modified. The original code, that applies Mollire`s multiple scattering theory and Vavilov`s energy straggling theory, calculates depth dose profiles, energy distributions and radial distributions for pencil beams in water. Comparisons with measurements and calculations reported in the literature are done to test the program`s accuracy. Preliminary results of the influence of chamber design and chamber materials on dose to water determination are presented.
International Nuclear Information System (INIS)
In the last decade, several clinical proton beam therapy facilities have been developed. To satisfy the demand for uniformity in clinical (routine) proton beam dosimetry two dosimetry protocols (ECHED and AAPM) have been published. Both protocols neglect the influence of ion chamber dependent parameters on dose determination in proton beams because of the scatter properties of these beams, although the problem has not been studied thoroughly yet. A comparison between water calorimetry and ionisation chamber dosimetry showed a discrepancy of 2.6% between the former method and ionometry following the ECHED protocol. Possibly, a small part of this difference can be attributed to chamber dependent correction factors. Indications for this possibility are found in ionometry measurements. To allow the simulation of complex geometries with different media necessary for the study of those corrections, an existing proton Monte Carlo code (PTRAN, Berger) has been modified. The original code, that applies Mollire's multiple scattering theory and Vavilov's energy straggling theory, calculates depth dose profiles, energy distributions and radial distributions for pencil beams in water. Comparisons with measurements and calculations reported in the literature are done to test the program's accuracy. Preliminary results of the influence of chamber design and chamber materials on dose to water determination are presented
Bai, Yan; Cao, Changyong; Shao, Xi
2015-09-01
The low gain stage of VIIRS Day/Night Band (DNB) on Suomi-NPP is calibrated using onboard solar diffuser. The calibration is then transferred to the high gain stage of DNB based on the gain ratio determined from data collected along solar terminator region. The calibration transfer causes increase of uncertainties and affects the accuracy of the low light radiances observed by DNB at night. Since there are 32 aggregation zones from nadir to the edge of the scan and each zone has its own calibration, the calibration versus scan angle of DNB needs to be independently assessed. This study presents preliminary analysis of the scan-angle dependence of the light intensity from bridge lights, oil platforms, power plants, and flares observed by VIIRS DNB since 2014. Effects of atmospheric path length associated with scan angle are analyzed. In addition, other effects such as light changes at the time of observation are also discussed. The methodology developed will be especially useful for JPSS J1 VIIRS due to the nonlinearity effects at high scan angles, and the modification of geolocation software code for different aggregation modes. It is known that J1 VIIRS DNB has large nonlinearity across aggregation zones, and requires new aggregation modes, as well as more comprehensive validation.
Identification of the PLK2-dependent phosphopeptidome by quantitative proteomics [corrected].
Directory of Open Access Journals (Sweden)
Cinzia Franchin
Full Text Available Polo-like kinase 2 (PLK2 has been recently recognized as the major enzyme responsible for phosphorylation of α-synuclein at S129 in vitro and in vivo, suggesting that this kinase may play a key role in the pathogenesis of Parkinson's disease and other synucleinopathies. Moreover PLK2 seems to be implicated in cell division, oncogenesis, and synaptic regulation of the brain. However little is known about the phosphoproteome generated by PLK2 and, consequently the overall impact of PLK2 on cellular signaling. To fill this gap we exploited an approach based on in vitro kinase assay and quantitative phosphoproteomics. A proteome-derived peptide library obtained by digestion of undifferentiated human neuroblastoma cell line was exhaustively dephosphorylated by lambda phosphatase followed by incubation with or without PLK2 recombinant kinase. Stable isotope labeling based quantitative phosphoproteomics was applied to identify the phosphosites generated by PLK2. A total of 98 unique PLK2-dependent phosphosites from 89 proteins were identified by LC-MS/MS. Analysis of the primary structure of the identified phosphosites allowed the detailed definition of the kinase specificity and the compilation of a list of potential PLK2 targets among those retrieved in PhosphositePlus, a curated database of in cell/vivo phosphorylation sites.
Energy Technology Data Exchange (ETDEWEB)
Matoori, Simon [Paracelsus Medical University Salzburg, Department of Radiology, Salzburg (Austria); Hirslanden Clinic St. Anna, Clinical Research Group, Lucerne (Switzerland); Froehlich, Johannes M. [Hirslanden Clinic St. Anna, Clinical Research Group, Lucerne (Switzerland); ETH Zurich, Department of Chemistry and Applied Biosciences, Institute of Pharmaceutical Sciences, Zurich (Switzerland); Cantonal Hospital Winterthur, Department of Radiology, Winterthur (Switzerland); Breitenstein, Stefan [Cantonal Hospital Winterthur, Department of Surgery, Clinic for Visceral and Thoracic Surgery, Winterthur (Switzerland); Doert, Aleksis [Cantonal Hospital Winterthur, Department of Radiology, Winterthur (Switzerland); Pozdniakova, Viktoria [Stavanger University Hospital, Department of Radiology, Stavanger (Norway); Koh, Dow-Mu [Royal Marsden Hospital, Department of Radiology, Surrey, England (United Kingdom); Gutzeit, Andreas [Paracelsus Medical University Salzburg, Department of Radiology, Salzburg (Austria); Hirslanden Clinic St. Anna, Clinical Research Group, Lucerne (Switzerland); Cantonal Hospital Winterthur, Department of Radiology, Winterthur (Switzerland)
2016-06-15
To identify correlations of signal enhancements (SE) and SE normalized to reference tissues of the spleen, kidney, liver, musculus erector spinae (MES) and ductus hepatocholedochus (DHC) on hepatobiliary phase gadoxetate-enhanced MRI with patient age in non-cirrhotic patients. A heterogeneous cohort of 131 patients with different clinical backgrounds underwent a standardized 3.0-T gadoxetate-enhanced liver MRI between November 2008 and June 2013. After exclusion of cirrhotic patients, a cohort of 75 patients with no diagnosed diffuse liver disease was selected. The ratio of signal intensity 20 min post- to pre-contrast administration (SE) in the spleen, kidney, liver, MES and DHC, and the SE of the kidney, liver and DHC normalized to the reference tissues spleen or MES were compared to patient age. Patient age was inversely correlated with the liver SE normalized to the spleen and MES SE (both p < 0.001) and proportionally with the SE of the spleen (p = 0.043), the MES (p = 0.030) and the kidney (p = 0.022). No significant correlations were observed for the DHC (p = 0.347) and liver SE (p = 0.606). The age dependence of hepatic SE normalized to the enhancement in the spleen and MES calls for a cautious interpretation of these quantification methods. (orig.)
Tripathi, S.; Haque, S. Maidul; Rao, K. Divakar; Misal, J. S.; Pratap, C.; Sahoo, N. K.
2016-05-01
Experiments were carried out on Ta2O5 oxide thin films by asymmetric bipolar pulsed DC magnetron sputtering using a new hybrid combination of conventional (normal incidence) deposition and glancing angle deposition (GLAD) geometries. The films were prepared with varying O2 partial pressure. The ellipsometry characterization reveals a systematic variation in refractive index, which decreased from 2.2 in the normal films to an average 1.78 in the GLAD films. The bandgap of these GLAD films is slightly higher as compared to normal films. Overall transmission of the GLAD films is increased is by ~ 15 % implying a reduction in the refractive index for potential optical filtering device applications. The results were further supported by X-ray reflectivity measurements which show an effective double layer structure in GLAD consisting of layers with different densities of the same Ta2O5 material.
Institute of Scientific and Technical Information of China (English)
李兴隆; 王晓鸣; 姚文进; 吴巍
2014-01-01
To get the direction of correction force which leads to the higher impact-point accuracy of semi-active laser impulse terminal correction projectile(TCP),a new method of impact point prediction compensation added to the calculation of traditional firing phase angle was proposed. The target-orientation model of laser detector was established.The improved firing phase angle was deduced by analyzing the longitudinal and lateral correction capability by impulse forces.A 6-DOF traj ectory simulation was used to validate the proposed method.The results show that the average miss distance decreases from 19.9 m to 13.1 m,and the circular error probability decreases from 27.7m to 12.4m after the ballistic correction under the proposed firing phase angle compared with the traditional firing phase angle.The proposed method is effective,and it provides a theoretical basis for the design of control strategy of TCP.%为得到脉冲控制激光半主动末段修正弹落点精度更高的修正力作用方向,提出在传统点火相位计算基础上加入落点预测补偿,并通过建立激光探测器目标方位模型,结合脉冲力的纵向和横向修正能力的分析,推导出改进后的点火相位。采用六自由度弹道仿真进行验证,结果表明,采用文中点火相位进行弹道修正后,落点偏差明显减小,平均脱靶量从56.3 m减小到13.1 m,圆概率误差从48.1 m减小到12.4 m,证明了该方法的有效性,为末段修正弹控制策略的设计提供了理论依据。
Gau, Chia-Ling; Rosenblatt, Robin A; Cerullo, Vincenzo; Lay, Fides D; Dow, Adrienne C; Livesay, Justin; Brunetti-Pierri, Nicola; Lee, Brendan; Cederbaum, Stephen D; Grody, Wayne W; Lipshutz, Gerald S
2009-01-01
Neonatal gene therapy has the potential to ameliorate abnormalities before disease onset. Our gene knockout of arginase I (AI) deficiency is characterized by increasing hyperammonemia, neurological deterioration, and early death. We constructed a helper-dependent adenoviral vector (HDV) carrying AI and examined for correction of this defect. Neonates were administered 5 × 109 viral particles/g and analyzed for survival, arginase activity, and ammonia and amino acids levels. The life expectancy of arg−/− mice increased to 27 days while controls died at 14 days with hyperammonemia and in extremis. Death correlated with a decrease in viral DNA/RNA per cell as liver mass increased. Arginase assays demonstrated that vector-injected hepatocytes had ~20% activity of heterozygotes at 2 weeks of age. Hepatic arginine and ornithine in treated mice were similar to those of saline-injected heterozygotes at 2 weeks, whereas ammonia was normal. By 26 days, arginase activity in the treated arg−/− livers declined to <10%, and arginine and ornithine increased. Ammonia levels began increasing by day 25, suggesting the cause of death to be similar to that of uninjected arg−/− mice, albeit at a later time. These studies demonstrate that the AI deficient newborn mouse can be temporarily corrected and rescued using a HDV. PMID:19367256
International Nuclear Information System (INIS)
We show that certain one-loop corrections to superstring effective four-dimensional lagrangians, involving non-harmonic field-dependent renormalization of gauge couplings, can be consistently written in a standard N=1 supergravity form, preserving target-space duality. The preservation of target-space duality is due both to a four-dimensional Green-Schwarz mechanism and to local terms, coming from non-local chiral superfields, originated by mixed gauge-σ-model anomaly diagrams. In some models, the Green-Schwarz mechanism is sufficient to achieve complete anomaly cancellation. In more general models automorphic functions, generated by the integration over the heavy string modes, are required to preserve target-space duality. (orig.)
Smith, Simon E; Landorf, Karl B; Butterworth, Paul A; Menz, Hylton B
2012-01-01
The chevron and scarf osteotomies are commonly used for the surgical management of hallux valgus (HV). However, there is debate as to whether one osteotomy provides more 1-2 intermetatarsal (1-2 IMA) correction than the other. The objective of this systematic review and meta-analysis was to compare the effectiveness of 3 types of first metatarsal osteotomy for reducing the 1-2 IMA in HV correction: the chevron osteotomy, the long plantar arm (modified) chevron osteotomy, and the scarf osteotomy. A systematic search for eligible studies was performed of the following databases: Medline, Embase (Ovid), CINAHL (EBSCO Host), and The Cochrane Database of Systematic Reviews and Cochrane Central Register of Controlled Clinical Trials. Only English-language studies previous to May 2010 were included in the review. Additional hand and electronic content searches of relevant foot and orthopaedic journals were performed. Criteria for inclusion in this analysis included systematic reviews of randomized controlled trials, prospective and retrospective cohort studies, and case-control studies, as well as case-series studies involving the chevron, scarf, or long plantar arm chevron osteotomy of >20 participants with a minimum of 80% follow-up. Quality of evidence of the included studies was assessed with the Grading of Recommendations Assessment, Development and Evaluation system. All pooled analyses were based on a fixed effects model. There was a total of 1351 participants who underwent either a chevron (n = 1028), scarf (n = 300), or long plantar arm chevron osteotomy (n = 23). Only one study for the long plantar arm chevron group fitted the eligibility criteria for this review; however, it was not amenable to meta-analysis. The chevron osteotomy was associated with a mean reduction of 1-2 IMA from preoperative to postoperative of 5.33° (95% confidence interval, 5.12 to 5.54, p < .001), and the scarf osteotomy was associated with a mean reduction of 6.21° (95% confidence
Mapping of low flip angles in magnetic resonance
Energy Technology Data Exchange (ETDEWEB)
Balezeau, Fabien; Saint-Jalmes, Herve [LTSI, INSERM U642, Universite Rennes 1 (France); Eliat, Pierre-Antoine [PRISM, IFR 140, Universite Rennes 1 (France); Cayamo, Alejandro Bordelois, E-mail: fabien.balezeau@gmail.com [Centro De BiofIsika Medica, Universidad de Oriente, Santiago de Cuba (Cuba)
2011-10-21
Errors in the flip angle have to be corrected in many magnetic resonance imaging applications, especially for T1 quantification. However, the existing methods of B1 mapping fail to measure lower values of the flip angle despite the fact that these are extensively used in dynamic acquisition and 3D imaging. In this study, the nonlinearity of the radiofrequency (RF) transmit chain, especially for very low flip angles, is investigated and a simple method is proposed to accurately determine both the gain of the RF transmitter and the B1 field map for low flip angles. The method makes use of the spoiled gradient echo sequence with long repetition time (TR), such as applied in the double-angle method. It uses an image acquired with a flip angle of 90{sup 0} as a reference image that is robust to B1 inhomogeneity. The ratio of the image at flip angle alpha to the image at a flip angle of 90{sup 0} enables us to calculate the actual value of alpha. This study was carried out at 1.5 and 4.7 T, showing that the linearity of the RF supply system is highly dependent on the hardware. The method proposed here allows us to measure the flip angle from 1{sup 0} to 60{sup 0} with a maximal uncertainty of 10% and to correct T1 maps based on the variable flip angle method.
De Giovannini, U; Marques, M A L; Appel, H; Gross, E K U; Rubio, A
2012-01-01
We present a time-dependent density-functional method able to describe the photoelectron spectrum of atoms and molecules when excited by laser pulses. This computationally feasible scheme is based on a geometrical partitioning that efficiently gives access to photoelectron spectroscopy in time-dependent density-functional calculations. By using a geometrical approach, we provide a simple description of momentum-resolved photoe- mission including multi-photon effects. The approach is validated by comparison with results in the literature and exact calculations. Furthermore, we present numerical photoelectron angular distributions for randomly oriented nitrogen molecules in a short near infrared intense laser pulse and helium-(I) angular spectra for aligned carbon monoxide and benzene.
Wang, Xue-Dong; Zhang, Jie-Ni; Liu, Da-Wei; Lei, Fei-fei
2016-01-01
In the present report, we describe the successful use of miniscrews to achieve vertical control in combination with the conventional sliding MBT™ straight-wire technique for the treatment of a 26-year-old Chinese woman with a very high mandibular plane angle, deep overbite, retrognathic mandible with backward rotation, prognathic maxilla, and gummy smile. The patient exhibited skeletal Class II malocclusion. Orthodontic miniscrews were placed in the maxillary anterior and posterior segments to provide rigid anchorage and vertical control through intrusion of the incisors and molars. Intrusion and torque control of the maxillary incisors relieved the deep overbite and corrected the gummy smile, while intrusion of the maxillary molars aided in counterclockwise rotation of the mandibular plane, which consequently resulted in an improved facial profile. After 3.5 years of retention, we observed a stable, well-aligned dentition with ideal intercuspation and more harmonious facial contours. Thus, we were able to achieve a satisfactory occlusion, a significantly improved facial profile, and an attractive smile for this patient. The findings from this case suggest that nonsurgical correction using miniscrew anchorage is an effective approach for camouflage treatment of high-angle cases with skeletal Class II malocclusion. PMID:27478802
International Nuclear Information System (INIS)
Nucleon electric dipole moments originating from strong CP-violation are being calculated by several groups using lattice QCD. We revisit the finite volume corrections to the CP-odd nucleon matrix elements of the electromagnetic current, which can be related to the electric dipole moments in the continuum, in the framework of chiral perturbation theory up to next-to-leading order taking into account the breaking of Lorentz symmetry. A chiral extrapolation of the recent lattice results of both the neutron and proton electric dipole moments is performed, which results in dn=(−2.7±1.2)×10−16eθ0 cm and dp=(2.1±1.2)×10−16eθ0 cm
International Nuclear Information System (INIS)
We present molecular above-threshold ionization (MATI) spectra generated by ultrashort intense linearly and circularly polarized laser pulses from nonperturbative numerical solutions of the corresponding time-dependent Schroedinger equation in the molecular-ion H2+. It is found that high-order MATI spectra with maximum kinetic energy 32Up, where Up=I0/4meω02 is the ponderomotive energy at intensity I0 and frequency ω0, can be obtained in H2+ at great internuclear distances R for both linear and circular polarizations. Quasiclassical laser-induced collision models confirm that such high-order MATIs mainly result from a collision with neighboring ions of the ionized electron. Interference patterns in the high-order MATI spectra are critically sensitive to both the internuclear distance R of the molecules and the polarizations of the driving laser pulses. Moreover, with few-cycle laser pulses, the carrier-envelope phase sensitivity of MATI angular distributions is also investigated for varying internuclear distances R. At critical internuclear distances for charge-resonance-enhanced ionization, we also find that enhanced interference patterns occur.
Directory of Open Access Journals (Sweden)
Tausif Alam
Full Text Available Type 1 diabetes mellitus (T1DM is caused by immune destruction of insulin-producing pancreatic β-cells. Commonly used insulin injection therapy does not provide a dynamic blood glucose control to prevent long-term systemic T1DM-associated damages. Donor shortage and the limited long-term success of islet transplants have stimulated the development of novel therapies for T1DM. Gene therapy-based glucose-regulated hepatic insulin production is a promising strategy to treat T1DM. We have developed gene constructs which cause glucose-concentration-dependent human insulin production in liver cells. A novel set of human insulin expression constructs containing a combination of elements to improve gene transcription, mRNA processing, and translation efficiency were generated as minicircle DNA preparations that lack bacterial and viral DNA. Hepatocytes transduced with the new constructs, ex vivo, produced large amounts of glucose-inducible human insulin. In vivo, insulin minicircle DNA (TA1m treated streptozotocin (STZ-diabetic rats demonstrated euglycemia when fasted or fed, ad libitum. Weight loss due to uncontrolled hyperglycemia was reversed in insulin gene treated diabetic rats to normal rate of weight gain, lasting ∼1 month. Intraperitoneal glucose tolerance test (IPGT demonstrated in vivo glucose-responsive changes in insulin levels to correct hyperglycemia within 45 minutes. A single TA1m treatment raised serum albumin levels in diabetic rats to normal and significantly reduced hypertriglyceridemia and hypercholesterolemia. Elevated serum levels of aspartate transaminase, alanine aminotransferase, and alkaline phosphatase were restored to normal or greatly reduced in treated rats, indicating normalization of liver function. Non-viral insulin minicircle DNA-based TA1m mediated glucose-dependent insulin production in liver may represent a safe and promising approach to treat T1DM.
X-ray diffraction at Bragg angles around π/2
International Nuclear Information System (INIS)
X-ray diffraction at Bragg angles around π/2 is studied from the theoretical and experimental points of view. The proposed corrections to the dynamical theory in the θβ ≅ π/2 cases, has been reviewed showing the equivalence between two formalisms leading to a corrected expression for the dependence of the angular parameter y with the angle of incidence. An expression for y valid in the conventional and θ β ≅ π/2 cases has been obtained. A general expression for Bragg law and for energy resolution after a Bragg diffraction was also deduced. (author)
Energy Technology Data Exchange (ETDEWEB)
Dey, Rik, E-mail: rikdey@utexas.edu; Pramanik, Tanmoy; Roy, Anupam; Rai, Amritesh; Guchhait, Samaresh; Sonde, Sushant; Movva, Hema C. P.; Register, Leonard F.; Banerjee, Sanjay K. [Microelectronics Research Center, University of Texas at Austin, Austin, Texas 78758 (United States); Colombo, Luigi [Texas Instruments, Dallas, Texas 75243 (United States)
2014-06-02
We have studied angle dependent magnetoresistance of Bi{sub 2}Te{sub 3} thin film with field up to 9 T over 2–20 K temperatures. The perpendicular field magnetoresistance has been explained by the Hikami-Larkin-Nagaoka theory alone in a system with strong spin-orbit coupling, from which we have estimated the mean free path, the phase coherence length, and the spin-orbit relaxation time. We have obtained the out-of-plane spin-orbit relaxation time to be small and the in-plane spin-orbit relaxation time to be comparable to the momentum relaxation time. The estimation of these charge and spin transport parameters are useful for spintronics applications. For parallel field magnetoresistance, we have confirmed the presence of Zeeman effect which is otherwise suppressed in perpendicular field magnetoresistance due to strong spin-orbit coupling. The parallel field data have been explained using both the contributions from the Maekawa-Fukuyama localization theory for non-interacting electrons and Lee-Ramakrishnan theory of electron-electron interactions. The estimated Zeeman g-factor and the strength of Coulomb screening parameter agree well with the theory. Finally, the anisotropy in magnetoresistance with respect to angle has been described by the Hikami-Larkin-Nagaoka theory. This anisotropy can be used in anisotropic magnetic sensor applications.
International Nuclear Information System (INIS)
We examined using the phantom whether there would be the tendency of artifact generated by Multi Detector-row CT (MD-CT) and the angle dependence between artifact and the structure to a slice side. In addition whether it is artifact peculiar to MD-CT with use of Single Detector-row CT. Even if images are obtained by pith-up, to set the thin collimation is one of the methods reduce artifact. When we take clinical usefulness into consideration the images cannot be obtain by sufficient S/N ratio, duration of respiratory suspension and more thin-section. It is necessary to carry out further experiment and examinations obtain images into consideration. (author)
International Nuclear Information System (INIS)
Charge density wave (CDW) systems such as TbTe3 offer fascinating options for studying the correlation of electrons and the lattice. We investigate the ultrafast response of the charge density wave (CDW) phase in TbTe3 after femtosecond IR excitation using time- and angle-resolved photoemission. The time-dependent photoemission intensity at the Fermi level yields a characteristic time for the closing of the CDW bandgap. With increasing laser fluence the bandgap closes faster, pointing to an increasing slope of the excited potential energy surface. As function of electron momentum the amplitude of the response increases strongly at the position of the Fermi wave vector kF. These results vividly demonstrate that the CDW system is most susceptible to electronic excitations near kF and that these electronic perturbations drive collective excitations of the coupled electron-lattice system.
Hiramatsu, Ryo; Kubota, Hitoshi; Tsunegi, Sumito; Tamaru, Shingo; Yakushiji, Kay; Fukushima, Akio; Matsumoto, Rie; Imamura, Hiroshi; Yuasa, Shinji
2016-05-01
Out-of-plane (OP) precession in spin torque oscillators having an in-plane (IP) magnetized free layer and a perpendicularly magnetized reference layer was studied. The bias voltage (V B) and magnetic field angle (θ) dependence of the OP precession were investigated. The absolute values of the critical magnetic fields (H\\text{B}\\text{c - } and H\\text{B}\\text{c + }) between which OP precession is excited increased as V B increased and as θ changed from the IP to the OP direction. The IP components of H\\text{B}\\text{c +/- } converged to a constant value regardless of θ. This result indicates that excitation of OP precession is suppressed entirely by the IP component of the magnetic field, and the contribution of the OP component can be ignored. The experimentally observed precession behavior was successfully modeled by macrospin simulations.
Operational multi-angle hyperspectral remote sensing for feature detection
Bostater, Charles R.; Brooks, Donald K.
2013-10-01
Remote sensing results of land and water surfaces from airborne and satellite platforms are dependent upon the illumination geometry and the sensor viewing geometry. Correction of pushbroom hyperspectral imagery can be achieved using bidirectional reflectance factors (BRF's) image features based upon their multi-angle hyperspectral signatures. Ground validation of features and targets utilize non-imaging sensors such as hemispherical goniometers. In this paper, a new linear translation based hyperspectral imaging goniometer system is described. Imagery and hyperspectral signatures obtained from a rotation stage platform and the new linear non-hemispherical goniometer system shows applications and a multi-angle correction approach for multi-angle hyperspectral pushbroom imagery corrections. Results are presented in a manner in order to describe how ground, vessel and airborne based multi-angle hyperspectral signatures can be applied to operational hyperspectral image acquisition by the calculation of hyperspectral anisotropic signature imagery. The results demonstrate the analysis framework from the systems to water and coastal vegetation for exploitation of surface and subsurface feature or target detection based using the multi-angle radiative transfer based BRF's. The hyperspectral pushbroom multi-angle analysis methodology forms a basis for future multi-sensor based multi-angle change detection algorithms.
Dootz, Rolf; Pfohl, Thomas
2011-01-01
DNA interactions with polycations are not only important for our understanding of chromatin compaction but also for characterizing DNA-binding proteins involved in transcription, replication and repair. DNA is known to form several types of liquid-crystalline phases depending, among other factors, on polycation structure and charge density. Theoretical studies and simulations have predicted the wrapping of DNA around spherical positively charged polycations. As a potential mimic of the histone octamer or other DNA wrapping proteins, poly(amido amine) generation 6 (PAMAM6) dendrimers have been chosen for our study. The self-assembly of DNA induced by PAMAM6 has been investigated using small angle X-ray scattering (SAXS) in order to reveal the assemblies' structure dependence on the pH of the environment and on dendrimers concentration. We demonstrate that at pH 8.5 dense phases are formed and characterized by a 2D-columnar hexagonal lattice which is transformed into a 3D hexagonal lattice with increasing dendr...
Energy Technology Data Exchange (ETDEWEB)
Han, Yun; Hou, Guangjin; Suiter, Christopher L.; Ahn, Jinwoo; Byeon, In-Ja L.; Lipton, Andrew S.; Burton, Sarah D.; Hung, Ivan; Gorkov, Peter L.; Gan, Zhehong; Brey, William W.; Rice, David M.; Gronenborn, Angela M.; Polenova, Tatyana E.
2013-11-27
Maturation of HIV-1 virus into an infectious virion requires cleavage of the Gag polyprotein into its constituent domains and formation of a conical capsid core that encloses viral RNA and a small complement of proteins for replication. The final step of this process is the cleavage of the SP1 peptide from the CA-SP1 maturation intermediate, which triggers the condensation of the CA protein into a conical capsid. The mechanism of this step, including the conformation of the SP1 peptide in CA-SP1, is under intense debate. In this report, we examine the tubular assemblies of CA and the CA-SP1 maturation intermediate using Magic Angle Spinning NMR spectroscopy. At the magnetic fields of 19.9 T and above, tubular CA and CA-SP1 assemblies yield outstanding-quality 2D and 3D MAS NMR spectra, which are amenable to resonance assignments and detailed structural characterization. Dipolar- and scalar-based correlation experiments unequivocally indicate that SP1 peptide is in a random coil conformation and mobile in the assembled CA-SP1. Analysis of two sequence variants reveals that remarkably, the conformation of SP1 tail, of the functionally important CypA loop, and of the loop preceding helix 8 are sequence dependent and modulated by the residue variations at distal sites. These findings challenge the role of SP1 as a conformational switch in the maturation process and establish sequence-dependent conformational plasticity in CA.
Podzharenko, Volodymyr A.; Kulakov, Pavlo I.
2001-06-01
The photo-electric angle transmitter of rotation is offered, at which the output voltage is linear function of entering magnitude. In a transmitter the linear phototransducer is used on the basis of pair photo diode -- operating amplifier, which output voltage is linear function of the area of an illuminated photosensitive stratum, and modulator of a light stream of the special shape, which ensures a linear dependence of this area from an angle of rotation. The transmitter has good frequent properties and can be used for dynamic measurements of an angular velocity and angle of rotation, in systems of exact drives and systems of autocontrol.
Xia, Jing; Li, Xuan-Ze; Huang, Xing; Mao, Nannan; Zhu, Dan-Dan; Wang, Lei; Xu, Hua; Meng, Xiang-Min
2016-01-01
Anisotropic layered semiconductors have attracted significant interest due to the huge possibility of bringing new functionalities to thermoelectric, electronic and optoelectronic devices. Currently, most reports on anisotropy have concentrated on black phosphorus and ReS2, less effort has been contributed to other layered materials. In this work, two-dimensional (2D) orthorhombic SnS flakes on a large scale have been successfully synthesized via a simple physical vapor deposition method. Angle-dependent Raman spectroscopy indicated that the orthorhombic SnS flakes possess a strong anisotropic Raman response. Under a parallel-polarization configuration, the peak intensity of Ag (190.7 cm-1) Raman mode reaches the maximum when incident light polarization is parallel to the armchair direction of the 2D SnS flakes, which strongly suggests that the Ag (190.7 cm-1) mode can be used to determine the crystallographic orientation of the 2D SnS. In addition, temperature-dependent Raman characterization confirmed that the 2D SnS flakes have a higher sensitivity to temperature than graphene, MoS2 and black phosphorus. These results are useful for the future studies of the optical and thermal properties of 2D orthorhombic SnS.Anisotropic layered semiconductors have attracted significant interest due to the huge possibility of bringing new functionalities to thermoelectric, electronic and optoelectronic devices. Currently, most reports on anisotropy have concentrated on black phosphorus and ReS2, less effort has been contributed to other layered materials. In this work, two-dimensional (2D) orthorhombic SnS flakes on a large scale have been successfully synthesized via a simple physical vapor deposition method. Angle-dependent Raman spectroscopy indicated that the orthorhombic SnS flakes possess a strong anisotropic Raman response. Under a parallel-polarization configuration, the peak intensity of Ag (190.7 cm-1) Raman mode reaches the maximum when incident light polarization
International Nuclear Information System (INIS)
With the STARE radar system it is possible to measure, with high spatial and temporal resolution the electron drift velocity V/sub D/ and the relative amplitude of electron density fluctuations of 1-m wavelength in the auroral electrojet. These density fluctuations are generated by the combined effects of the two-stream and the gradient drift instabilities. We have determined the angular dependence of the backscatter intensity (which is proportional to the square of the amplitude of the density fluctuations) on the angle theta betweeen the electron drift direction and the direction from the scattering volume to the radar in the plane perpendicular to the magnetic field. We find a fluctuation minimum for theta = 900 and an increase towards theta = 00 over the whole velocity range up to 1000 m/s. This increase is small for velocities below the ion acoustic velocity C/sub N/ but reaches over 20 dB gain in the backscatter intensity (corresponding to a density fluctuation more than 10 times as great) for higher velocities. We explain that the backscatter is caused mainly by two-stream instability in the range cos theta>C/sub S//V/sub d/ and by secondary gradient drift instability elsewhere
Wang, Fen; Zhang, Xin; Lin, Ying; Wang, Lei; Zhu, Jianfeng
2016-02-24
Vividly structurally colored pigments produced by employing materials with high indices of refraction such as ZnS, TiO2, or ZrO2 have attracted great attention recently. Generally, pigments with high refractive index based on three-dimensional ordered macroporous (3DOM) structures were prepared by a colloidal crystal template method. However, the preparation of 3DOM structures is time-consuming. Moreover, it will also lead to iridescent colors. In this work, structurally colored pigments based on carbon-modified core-shell nanospheres of ZnS@SiO2 were prepared by a homogeneous deposition method, followed by a modified Stöber method and a calcination process. Compared with conventional method, the pigments prepared in our work shows high color saturation, enhanced stability and low angle dependent. Typical paints composed of pigments and ethanol could be spray coated on any substrates without limitation. These core-shell structural coloration pigments have potential applications for displays, colorimetric sensors, and pigments. PMID:26824514
Energy Technology Data Exchange (ETDEWEB)
Pingali, Sai Venkatesh [ORNL; O' Neill, Hugh Michael [ORNL; McGaughey, Joseph [ORNL; Urban, Volker S [ORNL; Rempe, Caroline S [ORNL; Petridis, Loukas [ORNL; Smith, Jeremy C [ORNL; Evans, Barbara R [ORNL; Heller, William T [ORNL
2011-01-01
Cellobiohydrolase I (Cel7A) of the fungus Trichoderma reesei (now classified as an anamorph of Hypocrea jecorina) hydrolyzes crystalline cellulose to soluble sugars, making it of key interest for producing fermentable sugars from biomass for biofuel production. The activity of the enzyme is pH-dependent, with its highest activity occurring at pH 4 5. To probe the response of the solution structure of Cel7A to changes in pH, we measured small angle neutron scattering of it in a series of solutions having pH values of 7.0, 6.0, 5.3, and 4.2. As the pH decreases from 7.0 to 5.3, the enzyme structure remains well defined, possessing a spatial differentiation between the cellulose binding domain and the catalytic core that only changes subtly. At pH 4.2, the solution conformation of the enzyme changes to a structure that is intermediate between a properly folded enzyme and a denatured, unfolded state, yet the secondary structure of the enzyme is essentially unaltered. The results indicate that at the pH of optimal activity, the catalytic core of the enzyme adopts a structure in which the compact packing typical of a fully folded polypeptide chain is disrupted and suggest that the increased range of structures afforded by this disordered state plays an important role in the increased activity of Cel7A through conformational selection.
Atmospheric correction algorithm with multidirectional POLDER data
Mitomi, Yasushi; Fukushima, Hajime; Takamura, Tamio
2002-01-01
The atmospheric correction in ocean color remote sensing ins the most significant technique to retrieve the water leaving radiances, which are less than 10 percent of the satellite radiances, and its main errors are occurred by the estimation errors of the aerosol property and quantity which are highly variable in both space and time. In this study, our main purpose is to develop the advanced atmospheric correction method by using multi-viewing satellite data. POLDER onboard ADEOS can acquire multi-direction reflectance up to 14 viewing angles. In order to evaluate the validity of the multi-angle algorithm, we tired to test the algorithm with POLDER data. Results of comparisons with OCTS algorithm show that this algorithm with 3 or 4 angles POLDER data is available to estimate the aerosol properties because it is not affected form the errors depend on the band ratio.
JPSS-1 VIIRS prelaunch RSB/DNB RVS characterization and water vapor correction
Lee, Shihyan; Cao, Changyong
2015-09-01
The accuracy of pre-launch VIIRS response versus scan angle (RVS) characterization is vitally important to the quality of calibrated radiance products. The RVS correct the optical system's scan angle dependency with respect to the calibrator scan angle. In this document, we describe the methodology used in JPSS-1 RSB RVS characterization and the efficacy of MODTRAN5 in water vapor correction. The RVS is characterized using a 2nd order polynomial fit over the measured scan angles. The results show high fitting accuracy for all bands except for M9 due to water vapor absorption. To improve M9 RVS, MODTRAN®5 is used to correction water vapor absorption variation during the RVS measurements. This correction greatly reduced M9 RVS characterization uncertainty with a RVS that is up to 0.4% difference compared with RVS prior to water vapor correction.
International Nuclear Information System (INIS)
To analyse the frequency of re-planning and its variability dependent on the IGRT correction strategy and on the modification of the dosimetric criteria for re-planning for the spinal cord in head and neck IG-IMRT. Daily kV-control-CTs of six head and neck patients (=175 CTs) were analysed. All volumes of interest were re-contoured using deformable image registration. Three IGRT correction strategies were simulated and the resulting dose distributions were computed for all fractions. Different sets of criteria with varying dose thresholds for re-planning were investigated. All sets of criteria ensure equivalent target coverage of both CTVs, but vary in the tolerance threshold of the spinal cord. The variations of the D95 and D2 in respect to the planned values ranged from -7% to +3% for both CTVs, and -2% to +6% for the spinal cord. Despite different correction vectors of the three IGRT strategies, the dosimetric differences were small. The number of fractions not requiring re-planning varied between 0% and 11% dependent on the applied IGRT correction strategy. In contrast, this number ranged between 32% and 70% dependent on the dosimetric thresholds, even though these thresholds were only gently modified. The more precise the planned dose needs to be maintained over the treatment course, the more frequently re-planning is required. The influence of different IGRT correction strategies, even though geometrically notable, was found to be of only limited relevance for the re-planning frequency. In contrast, the definition and modification of thresholds for re-planning have a major impact on the re-planning frequency
International Nuclear Information System (INIS)
The variety of corrective actions which have been attempted at many radioactive waste disposal sites points to less than ideal performance by present-day standards at many closed and presently-operating sites. In humid regions, most of the problems have encompassed some kind of water intrusion into the buried waste. In arid regions, the problems have centered on trench subsidence and intrusion by plant roots and animals. It is overwhelmingly apparent that any protective barrier for the buried waste, whether for water or biological intrusion, will depend on stable support from the underlying burial trenches. Trench subsidence must be halted, prevented, or circumscribed in some manner to assure this necessary long-term support. Final corrective actions will differ considerably from site to site, depending on unique geological, pedological, and meteorological environments. In the meantime, many of the shorter-term corrective actions described in this chapter can be implemented as immediate needs dictate
Institute of Scientific and Technical Information of China (English)
王学滨; 姚再兴; 潘一山
2004-01-01
The inclination angle of shear band is analyzed considering heterogeneity of rock material when a single shear band is formed in the center of specimen under triaxial compression. The analytical solution of post-peak axial stress-axial strain curve is deduced using the assumption that the total post-peak deformation is composed of entire uniform elastic deformation and localized shear plastic deformation dependent on the thickness of shear band. The obtained solution shows that the post-peak stiffness is related to the inclination angle of shear band,confining pressure,thickness of shear band and elastic modulus,etc. Using the solution,the expression for the inclination angle of shear band can be presented easily and it is dependent on constitutive parameters of rock material and geometry parameters of rock specimen. Larger dilation angle or loading rate leads to increment of the inclination angle. In addition,the inclination angle increases with the thickness of the shear band,which cannot be explained or forecasted by other existing solutions,such as Coulomb inclination,Roscoe inclination and Arthur inclination,etc.
Institute of Scientific and Technical Information of China (English)
吕海江; 闫新虎; 叶云秀; 蒋一; 张沛; 叶秋健
2007-01-01
Due to the change of the hardware and high voltage during the small angle GDH experiment datatakeing, the CO2 gas threshold Cherenkov detector on HRS at Hall-A in Jefferson Jlab(JLab) was calibrated for seven times. The ADC signals of the single photo-electron peak for all ten PMTs were scaled to two hundred.The electrons could be separated from π by the detector after the calibration correction.%在JLab的A大厅上的小角度GDH实验中,因为实验过程中硬件条件的变化,对位于高分辨谱仪上的CO2阈契仑柯夫探测器进行了多次刻度修正,并得到7套修正系数.单光电峰在阈契仑柯夫探测器的10个PMT中的信号响应均被调整到两百.通过对在该探测器中的信号响应的判断,本底π粒子可以被有效的去除.
The hole overlap correction and fission fragment detection efficiency in Makrofol
International Nuclear Information System (INIS)
Efficiency measurements for an SSNTD fission fragment detector have been analysed using the hole overlap correction of James et al. It is found that the measured efficiencies can be corrected, as required, to constant values which are independent of the fragment density. In the analysis the hole overlap probability is treated as a free parameter. Its dependence on fragment angle is established and examined in terms of increasing hole area with decreasing angle between the fragment and the foil. (author)
Directory of Open Access Journals (Sweden)
Shapovalov V.V. (Jr.
2015-05-01
Full Text Available Established that the use of psychoactive substances may lead to premature death. The most commonly used psychoactive substance is alcohol. The authors had previously been justified and suggested for implementation in the practice of medicine cupping method alcoholic tremor in the structure of withdrawal symptoms in alcohol dependence. The article presents an analysis of drugs for the pharmaceutical correction of the alcoholic tremor in the structure of withdrawal symptoms, which are included in the patent of the pharmaceutical correction for the alcohol dependence. According to the international ATC classification included 5 ATC codes clinical and pharmacological groups: "A", "B", "C», «N», «S». The analysis found that in circulation in the pharmaceutical market of Ukraine for the pharmacotherapy of alcohol dependence are mainly domestic remedies (23 pharmaceutical manufacturer that provide the range of nosology at 88.0%. The next step in the analysis was to determine the types of dosage forms used for the pharmacotherapy of alcohol dependence. Found that the dosage means presented in the form of injection solutions and infusion (36.0%, powders for the preparation of solution (suspension for ingestion (36.0% in the form of tablets or capsules (28.0%. At the last stage analyzed registration certificates and found that the registration for the medicines for pharmacotherapy of alcohol dependence are 2015 four international nonproprietary names (8 drugs until 2019 in 4 international nonproprietary names (11 drugs.
Rotondi, Renata; Varini, Elisa
2016-04-01
The long-term recurrence of strong earthquakes is often modelled by the stationary Poisson process for the sake of simplicity, although renewal and self-correcting point processes (with non-decreasing hazard functions) are more appropriate. Short-term models mainly fit earthquake clusters due to the tendency of an earthquake to trigger other earthquakes; in this case, self-exciting point processes with non-increasing hazard are especially suitable. In order to provide a unified framework for analyzing earthquake catalogs, Schoenberg and Bolt proposed the SELC (Short-term Exciting Long-term Correcting) model (BSSA, 2000) and Varini employed a state-space model for estimating the different phases of a seismic cycle (PhD Thesis, 2005). Both attempts are combinations of long- and short-term models, but results are not completely satisfactory, due to the different scales at which these models appear to operate. In this study, we split a seismic sequence in two groups: the leader events, whose magnitude exceeds a threshold magnitude, and the remaining ones considered as subordinate events. The leader events are assumed to follow a well-known self-correcting point process named stress release model (Vere-Jones, J. Phys. Earth, 1978; Bebbington & Harte, GJI, 2003, Varini & Rotondi, Env. Ecol. Stat., 2015). In the interval between two subsequent leader events, subordinate events are expected to cluster at the beginning (aftershocks) and at the end (foreshocks) of that interval; hence, they are modeled by a failure processes that allows bathtub-shaped hazard function. In particular, we have examined the generalized Weibull distributions, a large family that contains distributions with different bathtub-shaped hazard as well as the standard Weibull distribution (Lai, Springer, 2014). The model is fitted to a dataset of Italian historical earthquakes and the results of Bayesian inference are shown.
Helble, Tyler A; D'Spain, Gerald L; Campbell, Greg S; Hildebrand, John A
2013-11-01
This paper demonstrates the importance of accounting for environmental effects on passive underwater acoustic monitoring results. The situation considered is the reduction in shipping off the California coast between 2008-2010 due to the recession and environmental legislation. The resulting variations in ocean noise change the probability of detecting marine mammal vocalizations. An acoustic model was used to calculate the time-varying probability of detecting humpback whale vocalizations under best-guess environmental conditions and varying noise. The uncorrected call counts suggest a diel pattern and an increase in calling over a two-year period; the corrected call counts show minimal evidence of these features. PMID:24181982
Excited States of DNA Base Pairs Using Long-Range Corrected Time-Dependent Density Functional Theory
Jensen, Lasse; Govind, Niranjan
2009-08-01
In this work, we present a study of the excitation energies of adenine, cytosine, guanine, thymine, and the adenine-thymine (AT) and guanine-cytosine (GC) base pairs using long-range corrected (LC) density functional theory. We compare three recent LC functionals, BNL, CAM-B3LYP, and LC-PBE0, with B3LYP and coupled cluster results from the literature. We find that the best overall performance is for the BNL functional based on LDA. However, in order to achieve this good agreement, a smaller attenuation parameter is needed, which leads to nonoptimum performance for ground-state properties. B3LYP, on the other hand, severely underestimates the charge-transfer (CT) transitions in the base pairs. Surprisingly, we also find that the CAM-B3LYP functional also underestimates the CT excitation energy for the GC base pair but correctly describes the AT base pair. This illustrates the importance of retaining the full long-range exact exchange even at distances as short as that of the DNA base pairs. The worst overall performance is obtained with the LC-PBE0 functional, which overestimates the excitations for the individual bases as well as the base pairs. It is therefore crucial to strike a good balance between the amount of local and long-range exact exchange. Thus, this work highlights the difficulties in obtained LC functionals, which provides a good description of both ground- and excited-state properties.
Whiteman, D. N.; Cadirola, M.; Venable, D.; Calhoun, M.; Miloshevich, L; Vermeesch, K.; Twigg, L.; Dirisu, A.; Hurst, D.; Hall, E.; Jordan, A.; Voemel, H.
2012-01-01
The MOHAVE-2009 campaign brought together diverse instrumentation for measuring atmospheric water vapor. We report on the participation of the ALVICE (Atmospheric Laboratory for Validation, Interagency Collaboration and Education) mobile laboratory in the MOHAVE-2009 campaign. In appendices we also report on the performance of the corrected Vaisala RS92 radiosonde measurements during the campaign, on a new radiosonde based calibration algorithm that reduces the influence of atmospheric variability on the derived calibration constant, and on other results of the ALVICE deployment. The MOHAVE-2009 campaign permitted the Raman lidar systems participating to discover and address measurement biases in the upper troposphere and lower stratosphere. The ALVICE lidar system was found to possess a wet bias which was attributed to fluorescence of insect material that was deposited on the telescope early in the mission. Other sources of wet biases are discussed and data from other Raman lidar systems are investigated, revealing that wet biases in upper tropospheric (UT) and lower stratospheric (LS) water vapor measurements appear to be quite common in Raman lidar systems. Lower stratospheric climatology of water vapor is investigated both as a means to check for the existence of these wet biases in Raman lidar data and as a source of correction for the bias. A correction technique is derived and applied to the ALVICE lidar water vapor profiles. Good agreement is found between corrected ALVICE lidar measurments and those of RS92, frost point hygrometer and total column water. The correction is offered as a general method to both quality control Raman water vapor lidar data and to correct those data that have signal-dependent bias. The influence of the correction is shown to be small at regions in the upper troposphere where recent work indicates detection of trends in atmospheric water vapor may be most robust. The correction shown here holds promise for permitting useful upper
Whiteman, D. N.; Cadirola, M.; Venable, D.; Calhoun, M.; Miloshevich, L.; Vermeesch, K.; Twigg, L.; Dirisu, A.; Hurst, D.; Hall, E.; Jordan, A.; Vömel, H.
2012-11-01
The MOHAVE-2009 campaign brought together diverse instrumentation for measuring atmospheric water vapor. We report on the participation of the ALVICE (Atmospheric Laboratory for Validation, Interagency Collaboration and Education) mobile laboratory in the MOHAVE-2009 campaign. In appendices we also report on the performance of the corrected Vaisala RS92 radiosonde measurements during the campaign, on a new radiosonde based calibration algorithm that reduces the influence of atmospheric variability on the derived calibration constant, and on other results of the ALVICE deployment. The MOHAVE-2009 campaign permitted the Raman lidar systems participating to discover and address measurement biases in the upper troposphere and lower stratosphere. The ALVICE lidar system was found to possess a wet bias which was attributed to fluorescence of insect material that was deposited on the telescope early in the mission. Other sources of wet biases are discussed and data from other Raman lidar systems are investigated, revealing that wet biases in upper tropospheric (UT) and lower stratospheric (LS) water vapor measurements appear to be quite common in Raman lidar systems. Lower stratospheric climatology of water vapor is investigated both as a means to check for the existence of these wet biases in Raman lidar data and as a source of correction for the bias. A correction technique is derived and applied to the ALVICE lidar water vapor profiles. Good agreement is found between corrected ALVICE lidar measurments and those of RS92, frost point hygrometer and total column water. The correction is offered as a general method to both quality control Raman water vapor lidar data and to correct those data that have signal-dependent bias. The influence of the correction is shown to be small at regions in the upper troposphere where recent work indicates detection of trends in atmospheric water vapor may be most robust. The correction shown here holds promise for permitting useful upper
Misra, A
2000-01-01
The axial-gauge boson propagator contains 1/(n.k)^p-type singularities. These singularities have generally been treated by inventing prescriptions for them. We propose an alternative procedere for treating these singularities in the path-integral formalism using the known way of treating the 1/k^{2n}-type singularities in Lorentz-type gauges. For this purpose we use a finite field-dependent BRS transformation that inerpolates between the Lorentz and axial-type gauges. We arrive at the \\epsilon-dependent tree propagator in axial-type gauges.
International Nuclear Information System (INIS)
Measurements of mechanical properties by instrumented indentation rely heavily upon the relationship between the unloading contact stiffness, Su, the projected contact area, Ac, and the reduced modulus, Er. This relationship is written in the form Su = 2βEr(Ac/π)1/2, where β is a correction factor that depends on the material properties, the geometry of the indenter and also the penetration depth. Most of the time a constant value of β is used in experimental measurements, either 1.0 or a value around 1.05, which is not correct since β strongly depends on the penetration depth as demonstrated by finite element calculations (FEC) on purely elastic materials and also experimentally on the fused quartz, which is the usual sample used for calibration of the contact area function. Here, the dependence of β on the penetration depth and tip blunting is studied by FEC in the case of elastic–plastic materials generally encountered in engineering. The consequence of not taking into account the influence of β on hardness and elastic modulus measurements is also investigated.
Energy Technology Data Exchange (ETDEWEB)
Fischer, Stephan
2011-07-01
factors on the performance used up to now can be neglected. Depending on the collector type the incoming irradiance under a given angle of incidence as well as the diffuse irradiance show different impacts on the thermal performance of solar thermal collectors. This is taken into account by a new and general numerical model of the incidence angle modifier. The second part introduces a model based test procedure for solar thermal collectors. This test procedure and the numerical model described in part one enable the detailed description of the thermal performance of solar thermal collectors. The test procedures is applied to a flat plate collector, an evacuated tubular collector, a CPC collector and a parabolic through collector. By repeatedly testing the same collector and by conducting a detailed measurement uncertainty analysis it is shown that the procedure leads to reliable results. The third part introduces an additional numerical model, taking into account the heat transfer between the absorber and the collector fluid. Based on this numerical model a test and evaluation procedure is introduced that allows the use of measured data when the heat flux from absorber to fluid is reversed for evaluation. Using such data which can be gained e.g. during heat loss measurements without solar irradiance leads to a reduction of the test duration between 30 to 50% without a loss in accuracy. The procedure is demonstrated using a flat plate collector and an evacuated tubular collector. Finally the content and results of the thesis are summarised and rated. (orig.)
International Nuclear Information System (INIS)
Tamm-Dancoff and random-phase approximations are formulated in the canonical Hartree-Fock-Bogoliubov quasi-particle basis and adopted to compute the E1 response in Ca isotopes using an intrinsic Hamiltonian composed of a Vlowk potential, deduced from the CD-Bonn nucleon-nucleon interaction, corrected with phenomenological density dependent and spin-orbit terms. Attention is focused on the evolution of the dipole strength distribution, including the low-lying transitions associated to the pygmy resonance, in going from the N = Z 40Ca to Ca isotopes with neutron excess.
Royston, John; Amar, Jacques G
2009-10-01
The scaling of the monomer and island densities, island-size distribution (ISD), and capture-number distribution (CND) as a function of the fraction of occupied sites (coverage) and ratio D(h)/F of the monomer hopping rate D(h) to the (per site) monomer creation rate F are studied for the case of irreversible nucleation and growth of fractal islands in three dimensions (d=3) . We note that our model is a three-dimensional analog of submonolayer growth in the absence of island relaxation and may also be viewed as a simplified model of the early stages of vacancy cluster nucleation and growth under irradiation. In contrast to results previously obtained for point-islands in d=3 , for which mean-field behavior corresponding to a CND which is independent of island size was observed, our results indicate that for fractal islands the scaled CND increases approximately linearly with island size in the asymptotic limit of large D(h)/F . In addition, while the peak height of the scaled ISD for fractal islands appears to diverge with increasing D(h)/F , the dependence on D(h)/F is much weaker than for point-islands in d=3 . The results of a self-consistent rate-equation calculation for the coverage and D(h)/F dependence of the average island and monomer densities are also presented and good agreement with simulation results is obtained. For the case of point-islands, the value of the exponent chi describing the D(h)/F dependence of the island density at fixed coverage, e.g., N(sat) approximately (D(h)/F)-chi , is in good agreement with the value (chi=1/3) expected for irreversible growth. However, for both compact and fractal islands in d=3 , our results indicate that the value of chi (chi approximately 0.42) is significantly larger. In order to explain this behavior, an analytical expression [e.g., chi=d(f)/(3d(f)-2) ] for the dependence of chi on island fractal dimension d(f) in d=3 is derived and found to give reasonable agreement with our simulation and rate
Estimation of velocity vector angles using the directional cross-correlation method
DEFF Research Database (Denmark)
Kortbek, Jacob; Jensen, Jørgen Arendt
2006-01-01
A method for determining both velocity magnitude and angle in any direction is suggested. The method uses focusing along the velocity direction and cross-correlation for finding the correct velocity magnitude. The angle is found from beamforming directional signals in a number of directions and...... then select the angle with the highest normalized correlation between directional signals. The approach is investigated using Field II simulations and data from the experimental ultrasound scanner RASMUS and a circulating flow rig with a parabolic flow having a peak velocity of 0.3 m/s. A 7 MHz linear...... estimated with a high precision. The angle estimation performance is highly dependent on the choice of the time ktprf Tprf (correlation-time) between signals to correlate. One performance example is given with a fixed value of ktprf for all flow angles. The angle estimation on measured data for flow at 60...
Kataev, A. L.; Molokoedov, V. S.
2016-08-01
Recently the four-loop perturbative QCD contributions to the relations between pole and running masses of charm, bottom and top quarks were evaluated in the overline{MS} scheme with identical numerical error bars. In this work the flavour dependence of the O(αs4) correction to these asymptotic series is obtained in the semi-analytical form with the help of the least squares method. The numerical structure of the corresponding asymptotic perturbative relations between pole and running c -, b - and t -quark masses is considered and the theoretical errors of the O(αs4) contributions are discussed. The explicit dependence for these relations on the renormalization scale μ2 and the flavour number nl is presented.
Energy Technology Data Exchange (ETDEWEB)
Lu, Siyuan; Hwang, Youngdeok; Khabibrakhmanov, Ildar; Marianno, Fernando J.; Shao, Xiaoyan; Zhang, Jie; Hodge, Bri-Mathias; Hamann, Hendrik F.
2015-07-15
With increasing penetration of solar and wind energy to the total energy supply mix, the pressing need for accurate energy forecasting has become well-recognized. Here we report the development of a machine-learning based model blending approach for statistically combining multiple meteorological models for improving the accuracy of solar/wind power forecast. Importantly, we demonstrate that in addition to parameters to be predicted (such as solar irradiance and power), including additional atmospheric state parameters which collectively define weather situations as machine learning input provides further enhanced accuracy for the blended result. Functional analysis of variance shows that the error of individual model has substantial dependence on the weather situation. The machine-learning approach effectively reduces such situation dependent error thus produces more accurate results compared to conventional multi-model ensemble approaches based on simplistic equally or unequally weighted model averaging. Validation over an extended period of time results show over 30% improvement in solar irradiance/power forecast accuracy compared to forecasts based on the best individual model.
Rate of occurrence of dayside Pc 3,4 pulsations: The L-value dependence of the IMF cone angle effect
International Nuclear Information System (INIS)
The normalized rate of occurrence of dayside Pc 3,4 pulsations from L = 2.4 to 4.3 has a strong enhancement for low cone angles of the interplanetary magnetic field. When the angle of the IMF to the earth sun line, theta/sub BX/, in 150 or less the occurrence rate is 7-8 times the average rate at L = 2.4 to 2.8 and 2.2 to 3.5 times the average rate at L = 4 to 4.3. These waves disappear when the IMF is nearly at right angles to the sun-earth-line. This absence of pulsations occurs over the widest range of angles at lowest L-values. These observations are consistent with a source originating in the waves upstream of the subsolar bow shock which are transported by convection to the magnetopause where they couple to oscillations of magnetospheric field lines. Since the index of refraction of the magnetospheric plasma decreases with decreasing radial distance, except at the plasmapause, inward propagating waves should be refracted away from the radial direction. Thus, to reach low L-values the waves should couple near the stagnation point and propagate nearly radially inwards. Upstream waves should be convected to the stagnation point for only a limited range of theta/sub BX/. However, to reach higher L-values the coupling may be at later local times where cross streamline propagation can bring waves from a larger range of theta/sub BX/. The streamline geometry and its connection to the foreshock region is illustrated for a variety of IMF orientations using a simple approximation to the magnetosheath flow field
Teo, L P
2013-01-01
We derive analytically the asymptotic behavior of the Casimir interaction between a sphere and a plate when the distance between them, $d$, is much smaller than the radius of the sphere, $R$. The leading order and next-to-leading order terms are derived from the exact formula for the Casimir interaction energy. They are found to depend nontrivially on the dielectric functions of the objects. As expected, the leading order term coincides with that derived using the proximity force approximation. The result on the next-to-leading order term complements that found by Bimonte, Emig and Kardar [Appl. Phys. Lett. \\textbf{100}, 074110 (2012)] using derivative expansion. Numerical results are presented when the dielectric functions are given by the plasma model or the Drude model, with the plasma frequency (for plasma and Drude models) and relaxation frequency (for Drude model) given respectively by 9eV and 0.035eV, the conventional values used for gold metal. It is found that if plasma model is used instead of Drude...
Adare, A.; Afanasiev, S.; Aidala, C.; Ajitanand, N. N.; Akiba, Y; Al-Bataineh, H.; Alexander, J.; Aoki, K.; Aramaki, Y.; Atomssa, E. T.; Averbeck, R.; Awes, T. C.; Azmoun, B.; Babintsev, V.; Bai, M.
2014-01-01
Charged-pion-interferometry measurements were made with respect to the 2$^{\\rm nd}$- and 3$^{\\rm rd}$-order event plane for Au$+$Au collisions at $\\sqrt{s_{_{NN}}}=200$ GeV. A strong azimuthal-angle dependence of the extracted Gaussian-source radii was observed with respect to both the 2$^{\\rm nd}$- and 3$^{\\rm rd}$-order event planes. The results for the 2$^{\\rm nd}$-order dependence indicate that the initial eccentricity is reduced during the medium evolution, but not reversed in the final ...
Sulic, Desanka; Sreckovic, Vladimir; Mihajlov, A. A.
2016-07-01
The focus of this work is on the extraction of D-region electron density that is induced by the intensive X-ray flux under different solar zenith angle. The sensitivity of Very Low and Low Frequency (VLF and LF) propagation in the lower ionosphere makes it an ideal probe for remotely sensing the ambient state and localized perturbations of the ionosphere. The basis of this work is amplitude and phase data acquired by monitoring DHO/23.40 kHz and NSC/45.90 kHz radio signals during the period of ascending and maximum of the solar cycle 24. All the data were recorded at Belgrade station (44.85 ^{0} N, 20.38 ^{0} E) by AWESOME system. DHO-BEL and NSC-BEL are short paths with distances of 1300 and 953 km, respectively. These paths are in the same time zone. The diurnal amplitude and phase variations on VLF/LF radio signal against time vary in characteristic ways that are caused by solar zenith angles over path. Two amplitude minima are observed when sunrise and sunset terminators reach the middle of the propagation path. During daytime condition there are two amplitude minima (in morning and afternoon) developed under solar zenith angles χ ˜80 ^{0} over short path. In this study we considered amplitude and phase perturbations on VLF/LF radio signal induced by solar X-ray flares under solar zenith angles which are close with timings of amplitude minima during daytime under normal ionospheric condition. We expected and estimated differences in amplitude and phase perturbations on DHO/23.40 kHz and NSC/45.90 kHz radio signals induced by solar X-ray flares which occurrences are under solar zenith angles χ ≤ 80 ^{0}. The observations include solar flares with magnitudes in the range from C2 (I_{X} = 2 10^{-6} Wm^{-2} of X-ray flux in the band at 0.1 - 0.8 nm) to X2.1 (I_{X} = 2.1 10^{-4} Wm^{-2}) class. For example on 11 March 2015 occurred X2.1 class flare with maximum of intensity at 16:22 UT, when solar angle was χ = 81^{0} at Belgrade. One day before, under normal
Energy Technology Data Exchange (ETDEWEB)
Sim, Adelene Y.L.; Lipfert, Jan; Herschlag, Daniel; Doniach, Sebastian
2012-07-06
Short single-stranded nucleic acids are ubiquitous in biological processes and understanding their physical properties provides insights to nucleic acid folding and dynamics. We used small angle x-ray scattering to study 8-100 residue homopolymeric single-stranded DNAs in solution, without external forces or labeling probes. Poly-T's structural ensemble changes with increasing ionic strength in a manner consistent with a polyelectrolyte persistence length theory that accounts for molecular flexibility. For any number of residues, poly-A is consistently more elongated than poly-T, likely due to the tendency of A residues to form stronger base-stacking interactions than T residues.
Russell, C. T.; Luhmann, J. G.; Odera, T. J.; Stuart, W. F.
1983-01-01
When the angle of the IMF to the earth sun line is 15 deg or less, the occurrence rate of dayside Pc 3,4 pulsations in 7-8 times the average at L values of 2.4-2.8, and 2.2-3.5 times the average at L of 4-4.3. These waves disappear when the IMF is nearly at right angles to the sun-earth line. Such observations are consistent with a source originating in the waves upstream of the subsolar bow shock, which are transported by convection to the magnetopause. There, they couple to oscillations of magnetospheric field lines. Because the magnetospheric plasma's index of refraction decreases with radial distance except at the plasmapause, inwardly propagating waves should be refracted away from the radial direction. To reach low L values, the waves should therefore couple near the stagnation point and propagate nearly radially inwards. The streamline geometry and its connection to the foreshock region is illustrated for various IMF orientations, using a simple approximation to the magnetosheath flow field.
International Nuclear Information System (INIS)
Based on an experimental investigation of the recombination effect in plane parallel chambers, a relation is deduced that allows the correction to be calculated from the electrode spacing and from the dose per pulse. It is shown that the uncertainties caused by the application of the Boag formula for volume recombination (recommended in the International Code of Practice TRS-381) amount to not more than about 0.1% for conventional beams. Calculated recombinations are compared with experimental results concerning the dependence of the response of various commercial plane parallel chambers on the polarizing voltage. Since it cannot be excluded that particular chambers collect a non-negligible amount of charge from regions outside the designated collecting volume or that the effective polarizing voltage is reduced by poor contacts, it seems advisable to experimentally check the chambers before use and before application of the analytical relations. (author)
Gao, Shouting; Li, Xiaofan
2011-06-01
Effects of time-dependent large-scale forcing, solar zenith angle, and sea surface temperature on time-mean rainfall during the Tropical Ocean Global Atmosphere Coupled Ocean-Atmosphere Response Experiment (TOGA COARE) are examined through a partitioning analysis of a series of sensitivity cloud-resolving model experiment data based on surface rainfall budget. The model is forced by time-dependent large-scale forcing (LSF), solar zenith angle (SZA), and sea surface temperature (SST) in the control experiment and is forced only by either time-dependent LSF, SZA, or SST while others are replaced with their time averages in the sensitivity experiments. The rainfall associated with water vapor divergence and local atmospheric drying and hydrometeor loss/convergence has the largest contribution to total rainfall among eight rainfall types. The largest rainfall contribution is increased in the simulations where either time-dependent LSF, SZA, or SST is replaced with its average, whereas it is decreased in the simulation where COARE-derived large-scale vertical velocity is replaced with zero vertical velocity. The contribution of the rainfall associated with water vapor convergence to total rainfall is decreased in the simulations with time-mean LSF, SZA, and SST, whereas it is increased in the simulation without large-scale vertical velocity.
Adare, A; Afanasiev, S; Aidala, C; Ajitanand, N N; Akiba, Y; Al-Bataineh, H; Alexander, J; Aoki, K; Aramaki, Y; Atomssa, E T; Averbeck, R; Awes, T C; Azmoun, B; Babintsev, V; Bai, M; Baksay, G; Baksay, L; Barish, K N; Bassalleck, B; Basye, A T; Bathe, S; Baublis, V; Baumann, C; Bazilevsky, A; Belikov, S; Belmont, R; Bennett, R; Berdnikov, A; Berdnikov, Y; Bickley, A A; Bok, J S; Boyle, K; Brooks, M L; Buesching, H; Bumazhnov, V; Bunce, G; Butsyk, S; Camacho, C M; Campbell, S; Chen, C-H; Chi, C Y; Chiu, M; Choi, I J; Choudhury, R K; Christiansen, P; Chujo, T; Chung, P; Chvala, O; Cianciolo, V; Citron, Z; Cole, B A; Connors, M; Constantin, P; Csanád, M; Csörgő, T; Dahms, T; Dairaku, S; Danchev, I; Das, K; Datta, A; David, G; Denisov, A; Deshpande, A; Desmond, E J; Dietzsch, O; Dion, A; Donadelli, M; Drapier, O; Drees, A; Drees, K A; Durham, J M; Durum, A; Dutta, D; Edwards, S; Efremenko, Y V; Ellinghaus, F; Engelmore, T; Enokizono, A; En'yo, H; Esumi, S; Fadem, B; Fields, D E; Finger, M; Finger, M; Fleuret, F; Fokin, S L; Fraenkel, Z; Frantz, J E; Franz, A; Frawley, A D; Fujiwara, K; Fukao, Y; Fusayasu, T; Garishvili, I; Glenn, A; Gong, H; Gonin, M; Goto, Y; Granier de Cassagnac, R; Grau, N; Greene, S V; Grosse Perdekamp, M; Gunji, T; Gustafsson, H-Å; Haggerty, J S; Hahn, K I; Hamagaki, H; Hamblen, J; Han, R; Hanks, J; Hartouni, E P; Haslum, E; Hayano, R; He, X; Heffner, M; Hemmick, T K; Hester, T; Hill, J C; Hohlmann, M; Holzmann, W; Homma, K; Hong, B; Horaguchi, T; Hornback, D; Huang, S; Ichihara, T; Ichimiya, R; Ide, J; Ikeda, Y; Imai, K; Inaba, M; Isenhower, D; Ishihara, M; Isobe, T; Issah, M; Isupov, A; Ivanischev, D; Jacak, B V; Jia, J; Jin, J; Johnson, B M; Joo, K S; Jouan, D; Jumper, D S; Kajihara, F; Kametani, S; Kamihara, N; Kamin, J; Kang, J H; Kapustinsky, J; Karatsu, K; Kawall, D; Kawashima, M; Kazantsev, A V; Kempel, T; Khanzadeev, A; Kijima, K M; Kim, B I; Kim, D H; Kim, D J; Kim, E; Kim, E-J; Kim, S H; Kim, Y-J; Kinney, E; Kiriluk, K; Kiss, A; Kistenev, E; Kochenda, L; Komkov, B; Konno, M; Koster, J; Kotchetkov, D; Kozlov, A; Král, A; Kravitz, A; Kunde, G J; Kurita, K; Kurosawa, M; Kwon, Y; Kyle, G S; Lacey, R; Lai, Y S; Lajoie, J G; Lebedev, A; Lee, D M; Lee, J; Lee, K; Lee, K B; Lee, K S; Leitch, M J; Leite, M A L; Leitner, E; Lenzi, B; Li, X; Liebing, P; Linden Levy, L A; Liška, T; Litvinenko, A; Liu, H; Liu, M X; Love, B; Luechtenborg, R; Lynch, D; Maguire, C F; Makdisi, Y I; Malakhov, A; Malik, M D; Manko, V I; Mannel, E; Mao, Y; Masui, H; Matathias, F; McCumber, M; McGaughey, P L; Means, N; Meredith, B; Miake, Y; Mignerey, A C; Mikeš, P; Miki, K; Milov, A; Mishra, M; Mitchell, J T; Mohanty, A K; Morino, Y; Morreale, A; Morrison, D P; Moukhanova, T V; Murata, J; Nagamiya, S; Nagle, J L; Naglis, M; Nagy, M I; Nakagawa, I; Nakamiya, Y; Nakamura, T; Nakano, K; Newby, J; Nguyen, M; Niida, T; Nouicer, R; Nyanin, A S; O'Brien, E; Oda, S X; Ogilvie, C A; Oka, M; Okada, K; Onuki, Y; Oskarsson, A; Ouchida, M; Ozawa, K; Pak, R; Pantuev, V; Papavassiliou, V; Park, I H; Park, J; Park, S K; Park, W J; Pate, S F; Pei, H; Peng, J-C; Pereira, H; Peresedov, V; Peressounko, D Yu; Pinkenburg, C; Pisani, R P; Proissl, M; Purschke, M L; Purwar, A K; Qu, H; Rak, J; Rakotozafindrabe, A; Ravinovich, I; Read, K F; Reygers, K; Riabov, V; Riabov, Y; Richardson, E; Roach, D; Roche, G; Rolnick, S D; Rosati, M; Rosen, C A; Rosendahl, S S E; Rosnet, P; Rukoyatkin, P; Ružička, P; Sahlmueller, B; Saito, N; Sakaguchi, T; Sakashita, K; Samsonov, V; Sano, S; Sato, T; Sawada, S; Sedgwick, K; Seele, J; Seidl, R; Semenov, A Yu; Seto, R; Sharma, D; Shein, I; Shibata, T-A; Shigaki, K; Shimomura, M; Shoji, K; Shukla, P; Sickles, A; Silva, C L; Silvermyr, D; Silvestre, C; Sim, K S; Singh, B K; Singh, C P; Singh, V; Slunečka, M; Soltz, R A; Sondheim, W E; Sorensen, S P; Sourikova, I V; Sparks, N A; Stankus, P W; Stenlund, E; Stoll, S P; Sugitate, T; Sukhanov, A; Sziklai, J; Takagui, E M; Taketani, A; Tanabe, R; Tanaka, Y; Tanida, K; Tannenbaum, M J; Tarafdar, S; Taranenko, A; Tarján, P; Themann, H; Thomas, T L; Todoroki, T; Togawa, M; Toia, A; Tomášek, L; Torii, H; Towell, R S; Tserruya, I; Tsuchimoto, Y; Vale, C; Valle, H; van Hecke, H W; Vazquez-Zambrano, E; Veicht, A; Velkovska, J; Vértesi, R; Vinogradov, A A; Virius, M; Vrba, V; Vznuzdaev, E; Wang, X R; Watanabe, D; Watanabe, K; Watanabe, Y; Wei, F; Wei, R; Wessels, J; White, S N; Winter, D; Wood, J P; Woody, C L; Wright, R M; Wysocki, M; Xie, W; Yamaguchi, Y L; Yamaura, K; Yang, R; Yanovich, A; Ying, J; Yokkaichi, S; You, Z; Young, G R; Younus, I; Yushmanov, I E; Zajc, W A; Zhang, C; Zhou, S; Zolin, L
2014-06-01
Charged-pion-interferometry measurements were made with respect to the second- and third-order event plane for Au+Au collisions at sqrt[s_{NN}]=200 GeV. A strong azimuthal-angle dependence of the extracted Gaussian-source radii was observed with respect to both the second- and third-order event planes. The results for the second-order dependence indicate that the initial eccentricity is reduced during the medium evolution, which is consistent with previous results. In contrast, the results for the third-order dependence indicate that the initial triangular shape is significantly reduced and potentially reversed by the end of the medium evolution, and that the third-order oscillations are largely dominated by the dynamical effects from triangular flow. PMID:24949761
Adare, A; Aidala, C; Ajitanand, N N; Akiba, Y; Al-Bataineh, H; Alexander, J; Aoki, K; Aramaki, Y; Atomssa, E T; Averbeck, R; Awes, T C; Azmoun, B; Babintsev, V; Bai, M; Baksay, G; Baksay, L; Barish, K N; Bassalleck, B; Basye, A T; Bathe, S; Baublis, V; Baumann, C; Bazilevsky, A; Belikov, S; Belmont, R; Bennett, R; Berdnikov, A; Berdnikov, Y; Bickley, A A; Bok, J S; Boyle, K; Brooks, M L; Buesching, H; Bumazhnov, V; Bunce, G; Butsyk, S; Camacho, C M; Campbell, S; Chen, C -H; Chi, C Y; Chiu, M; Choi, I J; Choudhury, R K; Christiansen, P; Chujo, T; Chung, P; Chvala, O; Cianciolo, V; Citron, Z; Cole, B A; Connors, M; Constantin, P; Csanád, M; Csörgő, T; Dahms, T; Dairaku, S; Danchev, I; Das, K; Datta, A; David, G; Denisov, A; Deshpande, A; Desmond, E J; Dietzsch, O; Dion, A; Donadelli, M; Drapier, O; Drees, A; Drees, K A; Durham, J M; Durum, A; Dutta, D; Edwards, S; Efremenko, Y V; Ellinghaus, F; Engelmore, T; Enokizono, A; En'yo, H; Esumi, S; Fadem, B; Fields, D E; Finger, M; Jr., \\,; Fleuret, F; Fokin, S L; Fraenkel, Z; Frantz, J E; Franz, A; Frawley, A D; Fujiwara, K; Fukao, Y; Fusayasu, T; Garishvili, I; Glenn, A; Gong, H; Gonin, M; Goto, Y; de Cassagnac, R Granier; Grau, N; Greene, S V; Perdekamp, M Grosse; Gunji, T; Gustafsson, H -Å; Haggerty, J S; Hahn, K I; Hamagaki, H; Hamblen, J; Han, R; Hanks, J; Hartouni, E P; Haslum, E; Hayano, R; He, X; Heffner, M; Hemmick, T K; Hester, T; Hill, J C; Hohlmann, M; Holzmann, W; Homma, K; Hong, B; Horaguchi, T; Hornback, D; Huang, S; Ichihara, T; Ichimiya, R; Ide, J; Ikeda, Y; Imai, K; Inaba, M; Isenhower, D; Ishihara, M; Isobe, T; Issah, M; Isupov, A; Ivanischev, D; Jacak, B V; Jia, J; Jin, J; Johnson, B M; Joo, K S; Jouan, D; Jumper, D S; Kajihara, F; Kametani, S; Kamihara, N; Kamin, J; Kang, J H; Kapustinsky, J; Karatsu, K; Kawall, D; Kawashima, M; Kazantsev, A V; Kempel, T; Khanzadeev, A; Kijima, K M; Kim, B I; Kim, D H; Kim, D J; Kim, E; Kim, E -J; Kim, S H; Kim, Y -J; Kinney, E; Kiriluk, K; Kiss, Á; Kistenev, E; Kochenda, L; Komkov, B; Konno, M; Koster, J; Kotchetkov, D; Kozlov, A; Král, A; Kravitz, A; Kunde, G J; Kurita, K; Kurosawa, M; Kwon, Y; Kyle, G S; Lacey, R; Lai, Y S; Lajoie, J G; Lebedev, A; Lee, D M; Lee, J; Lee, K; Lee, K B; Lee, K S; Leitch, M J; Leite, M A L; Leitner, E; Lenzi, B; Li, X; Liebing, P; Levy, L A Linden; Liška, T; Litvinenko, A; Liu, H; Liu, M X; Love, B; Luechtenborg, R; Lynch, D; Maguire, C F; Makdisi, Y I; Malakhov, A; Malik, M D; Manko, V I; Mannel, E; Mao, Y; Masui, H; Matathias, F; McCumber, M; McGaughey, P L; Means, N; Meredith, B; Miake, Y; Mignerey, A C; Mikeš, P; Miki, K; Milov, A; Mishra, M; Mitchell, J T; Mohanty, A K; Morino, Y; Morreale, A; Morrison, D P; Moukhanova, T V; Murata, J; Nagamiya, S; Nagle, J L; Naglis, M; Nagy, M I; Nakagawa, I; Nakamiya, Y; Nakamura, T; Nakano, K; Newby, J; Nguyen, M; Niida, T; Nouicer, R; Nyanin, A S; O'Brien, E; Oda, S X; Ogilvie, C A; Oka, M; Okada, K; Onuki, Y; Oskarsson, A; Ouchida, M; Ozawa, K; Pak, R; Pantuev, V; Papavassiliou, V; Park, I H; Park, J; Park, S K; Park, W J; Pate, S F; Pei, H; Peng, J -C; Pereira, H; Peresedov, V; Peressounko, D Yu; Pinkenburg, C; Pisani, R P; Proissl, M; Purschke, M L; Purwar, A K; Qu, H; Rak, J; Rakotozafindrabe, A; Ravinovich, I; Read, K F; Reygers, K; Riabov, V; Riabov, Y; Richardson, E; Roach, D; Roche, G; Rolnick, S D; Rosati, M; Rosen, C A; Rosendahl, S S E; Rosnet, P; Rukoyatkin, P; Ružička, P; Sahlmueller, B; Saito, N; Sakaguchi, T; Sakashita, K; Samsonov, V; Sano, S; Sato, T; Sawada, S; Sedgwick, K; Seele, J; Seidl, R; Semenov, A Yu; Seto, R; Sharma, D; Shein, I; Shibata, T -A; Shigaki, K; Shimomura, M; Shoji, K; Shukla, P; Sickles, A; Silva, C L; Silvermyr, D; Silvestre, C; Sim, K S; Singh, B K; Singh, C P; Singh, V; Slunečka, M; Soltz, R A; Sondheim, W E; Sorensen, S P; Sourikova, I V; Sparks, N A; Stankus, P W; Stenlund, E; Stoll, S P; Sugitate, T; Sukhanov, A; Sziklai, J; Takagui, E M; Taketani, A; Tanabe, R; Tanaka, Y; Tanida, K; Tannenbaum, M J; Tarafdar, S; Taranenko, A; Tarján, P; Themann, H; Thomas, T L; Todoroki, T; Togawa, M; Toia, A; Tomášek, L; Torii, H; Towell, R S; Tserruya, I; Tsuchimoto, Y; Vale, C; Valle, H; van Hecke, H W; Vazquez-Zambrano, E; Veicht, A; Velkovska, J; Vértesi, R; Vinogradov, A A; Virius, M; Vrba, V; Vznuzdaev, E; Wang, X R; Watanabe, D; Watanabe, K; Watanabe, Y; Wei, F; Wei, R; Wessels, J; White, S N; Winter, D; Wood, J P; Woody, C L; Wright, R M; Wysocki, M; Xie, W; Yamaguchi, Y L; Yamaura, K; Yang, R; Yanovich, A; Ying, J; Yokkaichi, S; You, Z; Young, G R; Younus, I; Yushmanov, I E; Zajc, W A; Zhang, C; Zhou, S; Zolin, L
2014-01-01
Charged-pion-interferometry measurements were made with respect to the 2$^{\\rm nd}$- and 3$^{\\rm rd}$-order event plane for Au$+$Au collisions at $\\sqrt{s_{_{NN}}}=200$ GeV. A strong azimuthal-angle dependence of the extracted Gaussian-source radii was observed with respect to both the 2$^{\\rm nd}$- and 3$^{\\rm rd}$-order event planes. The results for the 2$^{\\rm nd}$-order dependence indicate that the initial eccentricity is reduced during the medium evolution, but not reversed in the final state, which is consistent with previous results. In contrast, the results for the 3$^{\\rm rd}$-order dependence indicate that the initial triangular shape is significantly reduced and potentially reversed by the end of the medium evolution, and that the 3$^{\\rm rd}$-order oscillations are largely dominated by the dynamical effects from triangular flow.
Institute of Scientific and Technical Information of China (English)
Li Yong-Qing; Li Jian; Ma Feng-Cai
2006-01-01
Collisional quantum interference (CQI) on the intramolecular rotational energy transfer is observed in an experiment with a static cell, and the integral interference angles are measured. To obtain more accurate information, an experiment with a molecular beam is carried out, and thereby the relationship between the differential interference angle and the scattering angle is obtained. Based on the first-Born approximation of time-dependent perturbation theory,the theoretical model of CQI is developed in an atom-diatom system in the condition of the molecular beam, with the long-range interaction potential taken into account. The method of measuring correctly the differential interference angle is presented. The tendencies of the differential interference angle changing with the impact parameter and relative velocity are discussed. The theoretical model presented here is important for understanding or performing the experiment in the molecular beam.
OPTIMIZATION OF TILT ANGLE FOR PHOTOVOLTAIC ARRAY
Ashok Kumar; N.S.Thakur,; Rahul Makade,; Maneesh Kumar Shivhar
2011-01-01
The performance of a solar radiation conversion system is affected by its tilt angle with the horizontal plane, thus photovoltaic array need to be tilted at the correct angle to maximize the performance of the System, This paper deals with the determination of optimum tilt angle for solar PV array in order to maximize incident solar irradiance. The model starts by calculating the monthly averaged daily solar irradiation components (direct, diffuse, ground- eflected) absorbed by the solar PV a...
Fissel, Laura M; Angilè, Francesco E; Ashton, Peter; Benton, Steven; Devlin, Mark J; Dober, Bradley; Fukui, Yasuo; Galitzki, Nicholas; Gandilo, Natalie N; Klein, J R; Li, Zhi-Yun; Korotkov, Andrei L; Martin, Peter G; Matthews, Tristan G; Moncelsi, Lorenzo; Nakamura, Fumitaka; Netterfield, C Barth; Novak, Giles; Pascale, Enzo; Poidevin, Frédérick; Santos, Fabio P; Savini, Giorgio; Scott, Douglas; Shariff, Jamil A; Soler, Juan D; Thomas, Nicholas E; Tucker, Carole E; Tucker, Gregory S; Ward-Thompson, Derek
2015-01-01
We present results for Vela C obtained during the 2012 flight of the Balloon-borne Large Aperture Submillimeter Telescope for Polarimetry (BLASTPol). We mapped polarized intensity across almost the entire extent of this giant molecular cloud, in bands centered at 250, 350, and 500 {\\mu}m. In this initial paper, we show our 500 {\\mu}m data smoothed to a resolution of 2.5 arcminutes (approximately 0.5 pc). We show that the mean level of the fractional polarization p and most of its spatial variations can be accounted for using an empirical three-parameter power-law fit, p = p_0 N^(-0.4) S^(-0.6), where N is the hydrogen column density and S is the polarization-angle dispersion on 0.5 pc scales. The decrease of p with increasing S is expected because changes in the magnetic field direction within the cloud volume sampled by each measurement will lead to cancellation of polarization signals. The decrease of p with increasing N might be caused by the same effect, if magnetic field disorder increases for high colum...
The Belle Collaboration; Kusaka, A.; Wang, C. C.; Ishino, H.
2007-01-01
We present a measurement of CP asymmetry using a time-dependent Dalitz plot analysis of B0 --> pi+pi-pi0 decays based on a 414/fb data sample containing 449M BB pairs. The data was collected on the $\\Upsilon$(4S) resonance with the Belle detector at the KEKB asymmetric energy e+e- collider. Combining our analysis with information on charged B decay modes, we perform a full Dalitz and isospin analysis and obtain a constraint on the CKM angle $\\phi_2$, 68 deg. < $\\phi_2$ < 95 deg. as the 68.3% ...
Casida, Mark E.; Jamorski, Christine; Casida, Kim C.; Salahub, Dennis R.
1998-03-01
This paper presents an evaluation of the performance of time-dependent density-functional response theory (TD-DFRT) for the calculation of high-lying bound electronic excitation energies of molecules. TD-DFRT excitation energies are reported for a large number of states for each of four molecules: N2, CO, CH2O, and C2H4. In contrast to the good results obtained for low-lying states within the time-dependent local density approximation (TDLDA), there is a marked deterioration of the results for high-lying bound states. This is manifested as a collapse of the states above the TDLDA ionization threshold, which is at -ɛHOMOLDA (the negative of the highest occupied molecular orbital energy in the LDA). The -ɛHOMOLDA is much lower than the true ionization potential because the LDA exchange-correlation potential has the wrong asymptotic behavior. For this reason, the excitation energies were also calculated using the asymptotically correct potential of van Leeuwen and Baerends (LB94) in the self-consistent field step. This was found to correct the collapse of the high-lying states that was observed with the LDA. Nevertheless, further improvement of the functional is desirable. For low-lying states the asymptotic behavior of the exchange-correlation potential is not critical and the LDA potential does remarkably well. We propose criteria delineating for which states the TDLDA can be expected to be used without serious impact from the incorrect asymptotic behavior of the LDA potential.
Fissel, Laura M.; Ade, Peter A. R.; Angilè, Francesco E.; Ashton, Peter; Benton, Steven J.; Devlin, Mark J.; Dober, Bradley; Fukui, Yasuo; Galitzki, Nicholas; Gandilo, Natalie N.; Klein, Jeffrey; Korotkov, Andrei L.; Li, Zhi-Yun; Martin, Peter G.; Matthews, Tristan G.; Moncelsi, Lorenzo; Nakamura, Fumitaka; Netterfield, Calvin B.; Novak, Giles; Pascale, Enzo; Poidevin, Frédérick; Santos, Fabio P.; Savini, Giorgio; Scott, Douglas; Shariff, Jamil A.; Diego Soler, Juan; Thomas, Nicholas E.; Tucker, Carole E.; Tucker, Gregory S.; Ward-Thompson, Derek
2016-06-01
We present results for Vela C obtained during the 2012 flight of the Balloon-borne Large Aperture Submillimeter Telescope for Polarimetry. We mapped polarized intensity across almost the entire extent of this giant molecular cloud, in bands centered at 250, 350, and 500 μm. In this initial paper, we show our 500 μm data smoothed to a resolution of 2.‧5 (approximately 0.5 pc). We show that the mean level of the fractional polarization p and most of its spatial variations can be accounted for using an empirical three-parameter power-law fit, p \\propto {{\\boldsymbol{N}}}-0.45 {{\\boldsymbol{S}}}-0.60, where N is the hydrogen column density and S is the polarization-angle dispersion on 0.5 pc scales. The decrease of p with increasing S is expected because changes in the magnetic field direction within the cloud volume sampled by each measurement will lead to cancellation of polarization signals. The decrease of p with increasing N might be caused by the same effect, if magnetic field disorder increases for high column density sightlines. Alternatively, the intrinsic polarization efficiency of the dust grain population might be lower for material along higher density sightlines. We find no significant correlation between N and S. Comparison of observed submillimeter polarization maps with synthetic polarization maps derived from numerical simulations provides a promising method for testing star formation theories. Realistic simulations should allow for the possibility of variable intrinsic polarization efficiency. The measured levels of correlation among p, N, and S provide points of comparison between observations and simulations.
Critical angle laser refractometer
International Nuclear Information System (INIS)
A simple laser refractometer based on the detection of the critical angle for liquids is presented. The calibrated refractometer presents up to 0.000 11 of uncertainty when the refractive index is in the range between 1.300 00 and 1.340 00. The experimental setup is easy to construct and the material needed is available at most optics laboratories. The calibration method is simple and can be used in other devices. The refractive index measurements in aqueous solutions of sodium chloride were carried out to test the device and a linear dependence between the refractive index and the salt concentration was found
Energy Technology Data Exchange (ETDEWEB)
Cantero, E.D. [Centro Atomico Bariloche and Instituto Balseiro, Comision Nacional de Energia Atomica, 8400 S.C. Bariloche (Argentina); Consejo Nacional de Investigaciones Cientificas y Technicas (Argentina); Lantschner, G.H.; Arista, N.R. [Centro Atomico Bariloche and Instituto Balseiro, Comision Nacional de Energia Atomica, 8400 S.C. Bariloche (Argentina)
2011-12-15
We have performed measurements of energy-angle distributions for low energy (E < 10 keV) hydrogen ions transmitted through thin amorphous carbon foils. The applicability of standard potentials for the description of the multiple scattering is tested by making comparisons of the experimental results with theoretical calculations using the model of Sigmund and Winterbon on a broad angular scale. The angular dependence of the energy loss for protons and deuterons is analyzed using the three-components model of Fama et al., that separately considers the contribution of elastic and inelastic mechanisms and the roughness effect. Additionally, the velocity dependence of the stopping power and the possible existence of isotopic and molecular effects in the energy loss is investigated by measurements with H{sup +}, D{sup +}, H{sub 2}{sup +} and D{sub 2}{sup +} beams of velocities between 0.15 and 0.6 a.u. Among other things the results show first that the angular distributions can be very well described with the multiple scattering formalism of Sigmund and Winterbon, secondly that the multiple scattering process follows the energy-angle scaling law: E*{Theta} equals constant, and thirdly that no isotopic effect (H{sup +} vs D{sup +}) is observed in the stopping cross-sections measured in the forward direction, which corresponds to inelastic energy loss
International Nuclear Information System (INIS)
A long-range corrected (LC) time-dependent density functional theory (TDDFT) incorporating relativistic effects with spin-orbit couplings is presented. The relativistic effects are based on the two-component zeroth-order regular approximation Hamiltonian. Before calculating the electronic excitations, we calculated the ionization potentials (IPs) of alkaline metal, alkaline-earth metal, group 12 transition metal, and rare gas atoms as the minus orbital (spinor) energies on the basis of Koopmans' theorem. We found that both long-range exchange and spin-orbit coupling effects are required to obtain Koopmans' IPs, i.e., the orbital (spinor) energies, quantitatively in DFT calculations even for first-row transition metals and systems containing large short-range exchange effects. We then calculated the valence excitations of group 12 transition metal atoms and the Rydberg excitations of rare gas atoms using spin-orbit relativistic LC-TDDFT. We found that the long-range exchange and spin-orbit coupling effects significantly contribute to the electronic spectra of even light atoms if the atoms have low-lying excitations between orbital spinors of quite different electron distributions.
Institute of Scientific and Technical Information of China (English)
薛凌云; 孙世荣
2016-01-01
The coordinate rotation digital compute (CORDIC ) algorithm is widely used in magnetic rotary encoder ,because of the noise and non‐orthogonal signal caused by encoder manufacturing and installation process , classic CORDIC algorithm has a big output angle error . This paper uses MATLAB simulation to produce the rotating magnetic field signals with noise signal . Firstly the signals should be processed by the mean value filter ,next according to the feature that angle error curve approximates the sine and cosine functions ,using CORDIC algorithm to process the value of the input signal ,and then shift the phase and again using the CORDIC algorithm to process the value of the input signal , finally deal with the difference between the results of two CORDIC algorithm processing .The simulation results show that the output angle error is between ‐0 .25°to 0 .25° ,so it effectively reduced the angle detection error ,and improved the angle detection accuracy .%CORDIC 算法在磁旋转编码器中被广泛使用，但受编码器制造与安装工艺所带来的噪声和信号非正交性的影响，经典 CORDIC 算法存在较大输出角度误差．采用 MATLAB 模拟产生含噪旋转磁场信号，首先对信号进行均值滤波，再根据角度误差曲线近似于正余弦函数的特点，对输入信号值运用 CORDIC 算法处理，然后对输入信号值移相后再运用 CORDIC 算法处理，并对两次CORDIC 算法结果进行差值处理，最终获得磁编码器输出角度值．仿真结果表明，输出角度的误差在－0．25°～0．25°之间，有效减少了角度检测误差，提高了角度检测精度．
Citalopram associated with acute angle-closure glaucoma: case report
Directory of Open Access Journals (Sweden)
Hassan Sabit
2005-10-01
Full Text Available Abstract Background Acute angle-closure glaucoma is a rare complication in patients receiving anti-depressant treatment. In the following case, we report the development of acute angle closure glaucoma in a patient who overdosed on Citalopram, an antidepressant, and discuss the possible etiological mechanisms for the condition. Case presentation We report a 54 year old, Caucasian lady, with depression and alcohol dependence syndrome, who developed acute angle-closure glaucoma after an overdose of Citalopram, along with alcohol. She was treated with medications and had bilateral Yag laser iridotomies to correct the glaucoma and has made complete recovery. In this case, the underlying cause for glaucoma appears to be related to the ingestion of Citalopram. Conclusion The patho-physiological basis for acute angle closure glaucoma in relation to antidepressant medications remains unclear. The authors suggest Citalopram may have a direct action on the Iris or Ciliary body muscle through serotonergic or anti-cholinergic mechanisms or both. This case highlights the importance of the awareness of the underlying risks, which may predispose an individual to develop acute angle-closure glaucoma, and reminds the clinicians the significance of history taking and examination of the eye before and after starting anti-depressants. This area needs to be further researched.
Recoil corrected bag model calculations for semileptonic weak decays
International Nuclear Information System (INIS)
Recoil corrections to various model results for strangeness changing weak decay amplitudes have been developed. It is shown that the spurious reference frame dependence of earlier calculations is reduced. The second class currents are generally less important than obtained by calculations in the static approximation. Theoretical results are compared to observations. The agreement is quite good, although the values for the Cabibbo angle obtained by fits to the decay rates are somewhat to large
Perception of perspective angles
Erkelens, C.J.
2015-01-01
We perceive perspective angles, that is, angles that have an orientation in depth, differently from what they are in physical space. Extreme examples are angles between rails of a railway line or between lane dividers of a long and straight road. In this study, subjects judged perspective angles bet
Kusaka, A; Ishino, H
2007-01-01
We present a measurement of CP asymmetry using a time-dependent Dalitz plot analysis of B0 --> pi+pi-pi0 decays based on a 414/fb data sample containing 449M BB pairs. The data was collected on the $\\Upsilon$(4S) resonance with the Belle detector at the KEKB asymmetric energy e+e- collider. Combining our analysis with information on charged B decay modes, we perform a full Dalitz and isospin analysis and obtain a constraint on the CKM angle $\\phi_2$, 68 deg. < $\\phi_2$ < 95 deg. as the 68.3% confidence interval for the $\\phi_2$ solution consistent with the standard model (SM). A large SM-disfavored region also remains.
He, Junfeng; Zhang, Wentao; Bok, Jin Mo; Mou, Daixiang; Zhao, Lin; Peng, Yingying; He, Shaolong; Liu, Guodong; Dong, Xiaoli; Zhang, Jun; Wen, J S; Xu, Z J; Gu, G D; Wang, Xiaoyang; Peng, Qinjun; Wang, Zhimin; Zhang, Shenjin; Yang, Feng; Chen, Chuangtian; Xu, Zuyan; Choi, H-Y; Varma, C M; Zhou, X J
2013-09-01
High-resolution laser-based angle-resolved photoemission measurements have been carried out on Bi2Sr2CaCu2O(8+δ) (Bi2212) superconductors to investigate momentum dependence of electron coupling with collective excitations (modes). Two coexisting energy scales are clearly revealed over a large momentum space for the first time in the superconducting state of the overdoped Bi2212 superconductor. These two energy scales exhibit distinct momentum dependence: one keeps its energy near 78 meV over a large momentum space while the other changes its energy from ∼40 meV near the antinodal region to ∼70 meV near the nodal region. These observations provide a new picture on momentum evolution of electron-boson coupling in Bi2212 that electrons are coupled with two sharp modes simultaneously over a large momentum space in the superconducting states. Their unusual momentum dependence poses a challenge to our current understanding of electron-mode-coupling and its role for high-temperature superconductivity in cuprate superconductors. PMID:25166699
International Nuclear Information System (INIS)
The purpose of this study was to evaluate the effect of megavoltage photon beam attenuation (PBA) by couch tops and to propose a method for correction of PBA. Four series of phantom measurements were carried out. First, PBA by the exact couch top (ECT, Varian) and Imaging Couch Top (ICT, BrainLAB) was evaluated using a water-equivalent phantom. Second, PBA by Type-S system (Med-Tec), ECT and ICT was compared with a spherical phantom. Third, percentage depth dose (PDD) after passing through ICT was measured to compare with control data of PDD. Forth, the gantry angle dependency of PBA by ICT was evaluated. Then, an equation for PBA correction was elaborated and correction factors for PBA at isocenter were obtained. Finally, this method was applied to a patient with hepatoma. PBA of perpendicular beams by ICT was 4.7% on average. With the increase in field size, the measured values became higher. PBA by ICT was greater than that by Type-S system and ECT. PBA increased significantly as the angle of incidence increased, ranging from 4.3% at 180 deg to 11.2% at 120 deg. Calculated doses obtained by the equation and correction factors agreed quite well with the measured doses between 120 deg and 180 deg of angles of incidence. Also in the patient, PBA by ICT was corrected quite well by the equation and correction factors. In conclusion, PBA and its gantry angle dependency by ICT were observed. This simple method using the equation and correction factors appeared useful to correct the isocenter dose when the PBA effect cannot be corrected by a treatment planning system. (author)
Pulsar Binary Birthrates with Spin-Opening Angle Correlations
O'Shaughnessy, Richard
2009-01-01
Empirical birthrate estimates for pulsar binaries depend on the fraction of sky subtended by the pulsar beam: the pulsar beaming fraction. This fraction depends on both the pulsar's opening angle and the misalignment angle between its spin and magnetic axes. Previous estimates use the average value for only two pulsars, i.e. PSRs B1913+16 and B1534+12. We explore how birthrate predictions depend on assumptions about opening angle and alignment, using empirically-motivated distributions to define an effective beaming correction factor, f_{b,eff}. For most known pulsars, we expect f_{b,eff} to be less than 6. We also calculate f_{b,eff} for PSRs J0737-3039A and J1141-6545, applying the currently available constraints for their beam geometry. Our median posterior birthrate predictions for tight PSR-NS binaries, wide PSR-NS binaries, and tight PSR-WD binaries are 89/Myr, 0.84/Myr, and 34/Myr, respectively. For pulsars with spin period between 10 ms and 100 ms, we marginalized our posterior birthrate distribution ...
Flight Calibration of the LROC Narrow Angle Camera
Humm, D. C.; Tschimmel, M.; Brylow, S. M.; Mahanti, P.; Tran, T. N.; Braden, S. E.; Wiseman, S.; Danton, J.; Eliason, E. M.; Robinson, M. S.
2016-04-01
Characterization and calibration are vital for instrument commanding and image interpretation in remote sensing. The Lunar Reconnaissance Orbiter Camera Narrow Angle Camera (LROC NAC) takes 500 Mpixel greyscale images of lunar scenes at 0.5 meters/pixel. It uses two nominally identical line scan cameras for a larger crosstrack field of view. Stray light, spatial crosstalk, and nonlinearity were characterized using flight images of the Earth and the lunar limb. These are important for imaging shadowed craters, studying ˜1 meter size objects, and photometry respectively. Background, nonlinearity, and flatfield corrections have been implemented in the calibration pipeline. An eight-column pattern in the background is corrected. The detector is linear for DN = 600--2000 but a signal-dependent additive correction is required and applied for DNdetector temperature and dark level was developed to command dark level offset. This avoids images with a cutoff at DN=0 and minimizes quantization error in companding. Absolute radiometric calibration is derived from comparison of NAC images with ground-based images taken with the Robotic Lunar Observatory (ROLO) at much lower spatial resolution but with the same photometric angles.
Aad, Georges; Abbott, Brad; Abdallah, Jalal; Abdel Khalek, Samah; Abdinov, Ovsat; Aben, Rosemarie; Abi, Babak; Abolins, Maris; AbouZeid, Ossama; Abramowicz, Halina; Abreu, Henso; Abulaiti, Yiming; Acharya, Bobby Samir; Adamczyk, Leszek; Adams, David; Addy, Tetteh; Adelman, Jahred; Adomeit, Stefanie; Adye, Tim; Aefsky, Scott; Aguilar-Saavedra, Juan Antonio; Agustoni, Marco; Ahlen, Steven; Ahmad, Ashfaq; Ahsan, Mahsana; Aielli, Giulio; Åkesson, Torsten Paul Ake; Akimoto, Ginga; Akimov, Andrei; Alam, Muhammad Aftab; Albert, Justin; Albrand, Solveig; Alconada Verzini, Maria Josefina; Aleksa, Martin; Aleksandrov, Igor; Alessandria, Franco; Alexa, Calin; Alexander, Gideon; Alexandre, Gauthier; Alexopoulos, Theodoros; Alhroob, Muhammad; Aliev, Malik; Alimonti, Gianluca; Alio, Lion; Alison, John; Allbrooke, Benedict; Allison, Lee John; Allport, Phillip; Allwood-Spiers, Sarah; Almond, John; Aloisio, Alberto; Alon, Raz; Alonso, Alejandro; Alonso, Francisco; Altheimer, Andrew David; Alvarez Gonzalez, Barbara; Alviggi, Mariagrazia; Amako, Katsuya; Amaral Coutinho, Yara; Amelung, Christoph; Ammosov, Vladimir; Amor Dos Santos, Susana Patricia; Amorim, Antonio; Amoroso, Simone; Amram, Nir; Anastopoulos, Christos; Ancu, Lucian Stefan; Andari, Nansi; Andeen, Timothy; Anders, Christoph Falk; Anders, Gabriel; Anderson, Kelby; Andreazza, Attilio; Andrei, George Victor; Anduaga, Xabier; Angelidakis, Stylianos; Anger, Philipp; Angerami, Aaron; Anghinolfi, Francis; Anisenkov, Alexey; Anjos, Nuno; Annovi, Alberto; Antonaki, Ariadni; Antonelli, Mario; Antonov, Alexey; Antos, Jaroslav; Anulli, Fabio; Aoki, Masato; Aperio Bella, Ludovica; Apolle, Rudi; Arabidze, Giorgi; Aracena, Ignacio; Arai, Yasuo; Arce, Ayana; Arfaoui, Samir; Arguin, Jean-Francois; Argyropoulos, Spyridon; Arik, Engin; Arik, Metin; Armbruster, Aaron James; Arnaez, Olivier; Arnal, Vanessa; Artamonov, Andrei; Artoni, Giacomo; Arutinov, David; Asai, Shoji; Asbah, Nedaa; Ask, Stefan; Åsman, Barbro; Asquith, Lily; Assamagan, Ketevi; Astalos, Robert; Astbury, Alan; Atkinson, Markus; Atlay, Naim Bora; Auerbach, Benjamin; Auge, Etienne; Augsten, Kamil; Aurousseau, Mathieu; Avolio, Giuseppe; Axen, David; Azuelos, Georges; Azuma, Yuya; Baak, Max; Bacci, Cesare; Bach, Andre; Bachacou, Henri; Bachas, Konstantinos; Backes, Moritz; Backhaus, Malte; Backus Mayes, John; Badescu, Elisabeta; Bagiacchi, Paolo; Bagnaia, Paolo; Bai, Yu; Bailey, David; Bain, Travis; Baines, John; Baker, Oliver Keith; Baker, Sarah; Balek, Petr; Balli, Fabrice; Banas, Elzbieta; Banerjee, Swagato; Banfi, Danilo; Bangert, Andrea Michelle; Bansal, Vikas; Bansil, Hardeep Singh; Barak, Liron; Baranov, Sergei; Barber, Tom; Barberio, Elisabetta Luigia; Barberis, Dario; Barbero, Marlon; Bardin, Dmitri; Barillari, Teresa; Barisonzi, Marcello; Barklow, Timothy; Barlow, Nick; Barnett, Bruce; Barnett, Michael; Baroncelli, Antonio; Barone, Gaetano; Barr, Alan; Barreiro, Fernando; Barreiro Guimarães da Costa, João; Bartoldus, Rainer; Barton, Adam Edward; Bartsch, Valeria; Basye, Austin; Bates, Richard; Batkova, Lucia; Batley, Richard; Battistin, Michele; Bauer, Florian; Bawa, Harinder Singh; Beale, Steven; Beau, Tristan; Beauchemin, Pierre-Hugues; Beccherle, Roberto; Bechtle, Philip; Beck, Hans Peter; Becker, Anne Kathrin; Becker, Sebastian; Beckingham, Matthew; Becks, Karl-Heinz; Beddall, Andrew; Beddall, Ayda; Bedikian, Sourpouhi; Bednyakov, Vadim; Bee, Christopher; Beemster, Lars; Beermann, Thomas; Begel, Michael; Belanger-Champagne, Camille; Bell, Paul; Bell, William; Bella, Gideon; Bellagamba, Lorenzo; Bellerive, Alain; Bellomo, Massimiliano; Belloni, Alberto; Beloborodova, Olga; Belotskiy, Konstantin; Beltramello, Olga; Benary, Odette; Benchekroun, Driss; Bendtz, Katarina; Benekos, Nektarios; Benhammou, Yan; Benhar Noccioli, Eleonora; Benitez Garcia, Jorge-Armando; Benjamin, Douglas; Bensinger, James; Benslama, Kamal; Bentvelsen, Stan; Berge, David; Bergeaas Kuutmann, Elin; Berger, Nicolas; Berghaus, Frank; Berglund, Elina; Beringer, Jürg; Bernard, Clare; Bernat, Pauline; Bernhard, Ralf; Bernius, Catrin; Bernlochner, Florian Urs; Berry, Tracey; Bertella, Claudia; Bertolucci, Federico; Besana, Maria Ilaria; Besjes, Geert-Jan; Bessidskaia, Olga; Besson, Nathalie; Bethke, Siegfried; Bhimji, Wahid; Bianchi, Riccardo-Maria; Bianchini, Louis; Bianco, Michele; Biebel, Otmar; Bieniek, Stephen Paul; Bierwagen, Katharina; Biesiada, Jed; Biglietti, Michela; Bilbao De Mendizabal, Javier; Bilokon, Halina; Bindi, Marcello; Binet, Sebastien; Bingul, Ahmet; Bini, Cesare; Bittner, Bernhard; Black, Curtis; Black, James; Black, Kevin
2013-01-01
Measurements of the variation of inclusive jet suppression as a function of relative azimuthal angle, $\\Delta\\phi$, with respect to the elliptic event plane provide insight into the path-length dependence of jet quenching. ATLAS has measured the $\\Delta\\phi$ dependence of jet yields in 0.14 nb$^{-1}$ of $\\sqrt{s_{NN}}$= 2.76 TeV Pb+Pb collisions at the LHC for jet transverse momenta $p_T$ > 45 GeV in different collision centrality bins using an underlying event subtraction procedure that accounts for elliptic flow. The variation of the jet yield with Delta phi was characterized by the parameter, $v_2^{jet}$, and the ratio of out-of-plane ($\\Delta\\phi ~ \\pi/2$) to in-plane ($\\Delta\\phi ~ 0$) yields. Non-zero $v_2^{jet}$ values were measured in all centrality bins for $p_T$ < 160 GeV. The jet yields are observed to vary by as much as 20% between in-plane and out-of-plane directions.
Institute of Scientific and Technical Information of China (English)
王智方; 胡侦明; 郝杰; 陈林; 汪礼军; 张晓军; 甘强; 何斌
2014-01-01
背景：研究认为单纯椎管减压治疗退行性腰椎侧凸并椎管狭窄难以获得长期疗效，因为单纯减压被视为一种医源性的腰椎失稳，从而加重腰椎畸形。 目的：分析腰后路减压、矫形固定、融合治疗退行性腰椎侧凸并椎管狭窄，半年随访矫正角度评价。 方法：退行性腰椎侧凸并椎管狭窄患者23例均采用腰后路减压、矫形固定、融合治疗。采用症状目测类比评估表、Oswestry功能障碍指数评分表、SF-36调查问卷、腰椎冠状位Cobb角对患者治疗前和末次随访时生活质量变化情况及矫正角度进行评价。 结果与结论：患者随访均超过6个月。Cobb 角治疗前平均(23.94±11.4)°，治疗后平均(10.28±6.93)°；治疗后末次随访患者平均目测类比评分显著低于治疗前(P OBJECTIVE:To analyze the effectiveness of posterior decompression, fixation and fusion in the treatment of degenerative lumbar scoliosis with stenosis and to evaluate corrective angle during half-year fol ow-up. METHODS:A total of 23 cases of degenerative lumbar scoliosis with stenosis underwent posterior decompression, fixation and fusion. Visual Analogue Scale, Oswestry disability index, 36-Item Short-Form Health Survey scale and the Cobb angle on the lumbar coronal film were used to assess the changes in quality of life and corrective angle before treatment and during final fol ow-up. RESULTS AND CONCLUSION:Al patients were fol owed up for at least 6 mouths. Mean Cobb angles were (23.94±11.4)° pretreatment and (10.28±6.93)° posttreatment. Mean Visual Analogue Scale scores were significantly lower posttreatment than pretreatment (P<0.05). Oswestry disability index scores were significantly lower posttreatment than pretreatment (P<0.05). The excellent and good rate of Oswestry disability index score was 83.33%. The eight scaled scores of 36-Item Short-Form Health Survey scale were significantly higher posttreatment
Directory of Open Access Journals (Sweden)
Denise Nicodemo
2007-10-01
facial changes in 29 patients, from both genres, between 17 and 46 years old, with indication of surgical treatment, in the preoperative (during orthodontic preparation and in the postoperative (six months after the surgery periods. METHODS: Questionnaires, applied during interviews, with questions based on the proposal by Grossbart & Sarwer were used. The technique of content analysis was used, in which the reason for choosing corrective surgery were represented in Category 1 (C1; fantasies related to the results of the corrective surgery (preoperative and performance (postoperative in Category 2 (C2; and expectations and satisfaction of the results of the corrective surgery in Category 3 (C3. The answers were grouped in the subcategories: aesthetics (SC1, functional (SC2, social situations (SC3, self-esteem (SC4 and professional (SC5. RESULTS: the results showed that the patients looked for corrective surgery for functional reasons (34.5%, aesthetics (30.9% and social (29.1%; wished to improve his/her social situation (40% and the aesthetics (32%, with the fulfillment of these wishes after the surgery. As for the expectations, 49.4% of the patients hoped to improve the functional aspect followed by aesthetics (26.9%; social situations (11.2% and self-esteem (6.7%. In all aspects the patients were very satisfied because of improvements in their diction, aesthetics, beauty, and the return to life without discrimination. CONCLUSIONS: It can be concluded that the patients looked for the corrective surgery with the motivation to improve their functional and aesthetics aspects, they fantasized to improve their social relations and appearance; and hoped, in a realistic way, that the corrective surgery would repaired the function and aesthetics - which are the objectives of the orthognathic surgery.
International Nuclear Information System (INIS)
Quantification accuracy and partial volume effect (PVE) of the Siemens Inveon PET scanner were evaluated. The influence of transmission source activities (40 and 160 MBq) on the quantification accuracy and the PVE were determined. Dynamic range, object size and PVE for different sphere sizes, contrast ratios and positions in the field of view (FOV) were evaluated. The acquired data were reconstructed using different algorithms and correction methods. The activity level of the transmission source and the total emission activity in the FOV strongly influenced the attenuation maps. Reconstruction algorithms, correction methods, object size and location within the FOV had a strong influence on the PVE in all configurations. All evaluated parameters potentially influence the quantification accuracy. Hence, all protocols should be kept constant during a study to allow a comparison between different scans. (paper)
International Nuclear Information System (INIS)
We report on the inter-layer oscillatory conductance of the two-dimensional organic superconductor (BEDO-TTF)2ReO4H2O measured in static and pulsed magnetic fields of up to 15 and 52 T, respectively. In agreement with previous in-plane studies, two Shubnikov-de Haas oscillation series linked to the two electron and the hole orbits are observed. The influence of the magnitude and orientation of the magnetic field with respect to the conducting plane is studied in the framework of the conventional two- and three-dimensional Lifshits-Kosevich (LK) model. Deviations of the data from this model are observed in low fields strongly tilted with respect to the normal to the conducting plane. In this latter case, the observed behaviour is consistent with an unexplained lowering of the cyclotron effective mass. At high magnetic field, the oscillatory data could have been compatible with the occurrence of a magnetic breakdown orbit built from the hole and electron orbits. However, the increase of the cyclotron effective mass, linked to the electron orbits, as the magnetic field increases above ∝12 T is consistent with a field-induced phase transition. In the lower field range, where the conventional LK model holds, the analysis of the angle dependence of the oscillations amplitude suggests significant renormalisation of the effective Lande factor. (orig.)
Adachi, I; Arinstein, K; Aulchenko, V; Aushev, T; Bakich, A M; Balagura, V; Barberio, E; Bedny, I; Belous, K S; Bitenc, U; Bondar, A; Bozek, A; Brako, M; Browder, T E; Chang, P; Chao, Y; Chen, A; Chen, W T; Cheon, B G; Chistov, R; Cho, I S; Choi, S K; Choi, Y; Dalseno, J; Dash, M; Eidelman, S; Gabyshev, N; Golob, B; Haba, J; Hara, K; Hayasaka, K; Hayashii, H; Hazumi, M; Heffernan, D; Hoshi, Y; Hou, W S; Hyun, H J; Iijima, T; Inami, K; Ishikawa, A; Ishino, H; Itoh, R; Iwasaki, M; Iwasaki, Y; Kah, D H; Kang, J H; Kawai, H; Kawasaki, T; Kichimi, H; Kim, H O; Kim, S K; Kim, Y J; Kinoshita, K; Korpar, S; Krian, P; Krokovny, P; Kumar, R; Kuo, C C; Kuzmin, A; Kwon, Y J; Lee, J S; Lee, M J; Lee, z S E; Lesiak, T; Limosani, A; Lin, S W; Liu, Y; Liventsev, D; Mandl, F; Matyja, A; McOnie, S; Medvedeva, T; Miyabayashi, K; Miyake, H; Miyata, H; Miyazaki, Y; Mizuk, R; Moloney, G R; Nakano, E; Nakao, M; Nishida, S; Nitoh, O; Noguchi, S; Nozaki, T; Ogawa, S; Ohshima, T; Okuno, S; Ozaki, H; Pakhlova, G; Park, C W; Park, H; Peak, L S; Pestotnik, R; Piilonen, L E; Sahoo, H; Sakai, Y; Schneider, O; Schwanda, C; Schwartz, A J; Senyo, K; Sevior, M E; Shapkin, M; Shen, C P; Shibuya, H; Shwartz, B; Singh, J B; Somov, A; Stani, S; Stari, M; Sumiyoshi, T; Suzuki, S; Suzuki, S Y; Takasaki, F; Tamai, K; Tamura, N; Tanaka, M; Teramoto, Y; Tikhomirov, I; Trabelsi, K; Uehara, S; Ueno, K; Uglov, T; Unno, Y; Uno, S; Urquijo, P; Varner, G; Varvell, K E; Vervink, K; Villa, S; Wang, C H; Wang, M Z; Wang, P; Wang, X L; Watanabe, Y; Won, E; Yamashita, Y; Zhang, Z P; Zhulanov, V; Zupanc, A; Zyukova, O
2007-01-01
We present the results of a time-dependent Dalitz plot analysis of B0 --> pi+ pi- pi0 decays based on a 414/fb data sample that contains 449 x 10^6 BB pairs. The data was collected on the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric energy e+e- collider. Combining our analysis with information on charged B decay modes, we perform a full Dalitz and isospin analysis and obtain a constraint on the quark mixing angle phi_2, 68deg. rho+-(770) pi-+ and B0 --> rho0(770) pi0 are measured to be (22.6 +- 1.1[stat.] +- 4.4 [syst.]) x 10^{-6} and (3.0 +- 0.5 [stat.] +- 0.7 [syst.]) x 10^{-6}, respectively. These are the first branching fraction measurements of the process B0 --> rho(770)pi with the lowest resonance rho(770) explicitly separated from the radial excitations.
Pitch angle of galactic spiral arms
International Nuclear Information System (INIS)
One of the key parameters that characterizes spiral arms in disk galaxies is a pitch angle that measures the inclination of a spiral arm to the direction of galactic rotation. The pitch angle differs from galaxy to galaxy, which suggests that the rotation law of galactic disks determines it. In order to investigate the relation between the pitch angle of spiral arms and the shear rate of galactic differential rotation, we perform local N-body simulations of pure stellar disks. We find that the pitch angle increases with the epicycle frequency and decreases with the shear rate and obtain the fitting formula. This dependence is explained by the swing amplification mechanism.
Ocular Biometry in Angle Closure
Directory of Open Access Journals (Sweden)
Mohammad Reza Razeghinejad
2013-01-01
Full Text Available Purpose: To compare ocular biometric parameters in primary angle closure suspects (PACS, primary angle closure glaucoma (PACG and acute primary angle closure (APAC. Methods: This cross-sectional study was performed on 113 patients including 33 cases of PACS, 45 patients with PACG and 35 subjects with APAC. Central corneal thickness (CCT, axial length (AL, anterior chamber depth (ACD and lens thickness (LT were measured with an ultrasonic biometer. Lens-axial length factor (LAF, relative lens position, corrected ACD (CACD and corrected lens position were calculated. The parameters were measured bilaterally but only data from the right eyes were compared. In the APAC group, biometric parameters were also compared between affected and unaffected fellow eyes. Logistic regression analysis was performed to identify risk factors. Results: No statistically significant difference was observed in biometric parameters between PACS and PACG eyes, or between affected and fellow eyes in the APAC group (P>0.05 for all comparisons. However, eyes with APAC had thicker cornea (P=0.001, thicker lens (P<0.0001, shallower ACD (P=0.009, shallower CACD (P=0.003 and larger LAF (P<0.0001. Based on ROC curve analysis, lower ACD, and larger LT, LAF and CCT values were associated with APAC. In the APAC group, LAF (P<0.0001 and CCT (P=0.001 were significant risk factors. Conclusion: This study revealed no significant difference in biometric characteristics in eyes with PACS and PACG. However, larger LAF and CCT were predictive of APAC.
Energy Technology Data Exchange (ETDEWEB)
Mora Melendez, R.; Seguro Fernandez, A.; Iborra Oquendo, M.; Urena Llinares, A.
2013-07-01
The main objective of our study is to find correction factors dependent on the 2D array incidence angles, and to give account of the phenomenon, allowing the Planner to faithfully reproduce data and curves measured experimentally. (Author)
International Nuclear Information System (INIS)
No prospective studies have evaluated the effects of correction of iron deficiency anemia on insulin resistance in non-diabetic premenopausal women with iron deficiency anemia. All patients were treated with oral iron preparations. Insulin resistance was calculated with the Homeostasis Model Assessment formula. All patients were dichotomized by the median for age and BMI to assess how the relationship between iron deficiency anemia and insulin resistance was affected by the age and BMI. Although the fasting glucose levels did not change meaningfully, statistically significant decreases were found in fasting insulin levels following anemia treatment both in the younger age (= 40 years) and the high BMI (>-27Kg/m) subgroups. Post-treatment fasting insulin levels were positively correlated both with BMI (r=0.386, P=0.004) and post-treatment hemoglobin levels. (r=0.285, P=0.036). Regression analysis revealed that the factors affecting post-treatment insulin levels were BMI (P=0.001) and post-treatment hemoglobin levels (p=0.030). Our results show that following he correction of iron deficiency anemia, insulin levels and HOMA scores decrease in younger and lean non-diabetic premenopausal women. (author)
Bera, Prasanta
2015-01-01
Recent literature has seen an ongoing discussion on the limiting mass of strongly magnetized white dwarfs, since such objects may prove to be a source of over-luminous type-Ia supernovae. In an earlier paper, we have presented the mass-radius relation of white dwarfs with a strong poloidal magnetic field in Newtonian gravity. The inclusion of effects such as general relativistic gravity and many-body corrections to the equation of state can alter the mass-radius relation and the maximum mass. In this work we estimate the extent to which these effects may modify the earlier results. We find that the general relativistic effects tend to reduce the maximum mass by about 2% and many-body corrections by another additional $\\sim$2%, for an assumed carbon composition. We also explore field geometries that are purely toroidal or a mixture of poloidal and toroidal and find that the limiting mass of such equilibrium configurations can be substantially higher than in the case of a purely poloidal field.
Izard, Véronique; O'Donnell, Evan; Spelke, Elizabeth S.
2014-01-01
Preschool children can navigate by simple geometric maps of the environment, but the nature of the geometric relations they use in map reading remains unclear. Here, children were tested specifically on their sensitivity to angle. Forty-eight children (age 47:15-53:30 months) were presented with fragments of geometric maps, in which angle sections…
Relativistic corrections to stopping powers
International Nuclear Information System (INIS)
Relativistic corrections to the nonrelativistic Bethe-Bloch formula for the stopping power of matter for charged particles are traditionally computed by considering close collisions separately from distant collisions. The close collision contribution is further divided into the Mott correction appropriate for very small impact parameters, and the Bloch correction, computed for larger values. This division of the region of close collisions leads to a very cumbersome result if one generalizes the original Bloch procedure to relativistic energies. The authors avoid the resulting poorly specified scattering angle theta/sub o/ that divides the Mott and Bloch correction regimes by using the procedure suggested by Lindhard and applied by Golovchenko, Cox and Goland to determine the Bloch correction for relativistic velocities. 25 references, 2 figures
International Nuclear Information System (INIS)
The question of optimal projection angles has recently become of interest in the field of reconstruction from projections. Here, studies are concentrated on the n x n pixel space, where literative algorithms such as ART and direct matrix techniques due to Katz are considered. The best angles are determined in a Gauss--Markov statistical sense as well as with respect to a function-theoretical error bound. The possibility of making photon intensity a function of angle is also examined. Finally, the best angles to use in an ART-like algorithm are studied. A certain set of unequally spaced angles was found to be preferred in several contexts. 15 figures, 6 tables
International Nuclear Information System (INIS)
The application of a non-destructive method for characterization of electronic structure of an ultra-thin SnO1
Energy Technology Data Exchange (ETDEWEB)
Krzywiecki, Maciej, E-mail: Maciej.Krzywiecki@polsl.pl [Max-Planck-Institut für Eisenforschung GmbH, Max-Planck-Str. 1, 40237 Düsseldorf (Germany); Institute of Physics–CSE, Silesian University of Technology, Konarskiego 22B, 44-100 Gliwice (Poland); Sarfraz, Adnan; Erbe, Andreas [Max-Planck-Institut für Eisenforschung GmbH, Max-Planck-Str. 1, 40237 Düsseldorf (Germany)
2015-12-07
The application of a non-destructive method for characterization of electronic structure of an ultra-thin SnO{sub 1
QCD corrections to triboson production
Lazopoulos, Achilleas; Melnikov, Kirill; Petriello, Frank
2007-07-01
We present a computation of the next-to-leading order QCD corrections to the production of three Z bosons at the Large Hadron Collider. We calculate these corrections using a completely numerical method that combines sector decomposition to extract infrared singularities with contour deformation of the Feynman parameter integrals to avoid internal loop thresholds. The NLO QCD corrections to pp→ZZZ are approximately 50% and are badly underestimated by the leading order scale dependence. However, the kinematic dependence of the corrections is minimal in phase space regions accessible at leading order.
Relationship Between Differential Interference Angle and Parameter of Experiment in Molecular Beam
Institute of Scientific and Technical Information of China (English)
LI Yong-Qing; LI Jian; MA Feng-Cai
2006-01-01
Collisional quantum interference (CQI) was observed in the intramolecular rotational energy transfer in the experiment of the static cell, and the integral interference angles were measured. To observe more precise information, the experiment in the molecular beam should be taken, from which the relationship between the differential interference angle and the scattering angle can be obtained. In this paper, the theoretical model of CQI is described in an atom-diatom system in the condition of the molecular beam, based on the first-Born approximation of time-dependent perturbation theory, taking into accounts the long-range interaction potential. The method of observing and measuring correctly the differential interference angle is presented. The changing tendency of the differential interference angle with the impact parameter and relative velocity is discussed. The changing tendencies of the differential interference angle with the parameter of experiment in the molecular beam, including the impact parameter and the velocity are discussed. This theoretical model is important to understand or perform the experiment in the molecular beam.
Lateral angle: a method for sexing using the petrous bone
DEFF Research Database (Denmark)
Norén, Anna; Lynnerup, Niels; Czarnetzki, Alfred;
2005-01-01
very fragmented skeletal remains or cremated bones, where the petrous bone may still be readily recognizable. The method was tested using a forensic sample of 113 petrous bones with known sex. Intra- and interobserver testing was also performed. We found a statistically significant difference in angle......We report on the results of applying the so-called lateral angle method for sex determination on skeletal remains. The lateral angle denotes the angle of the internal auditory canal in relation to the medial surface of the petrous part of the temporal bone. The method involves making a small cast...... size between males and females (mean angle size of males, 39.3 degrees ; mean angle size of females, 48.2 degrees ; P < 0.001). There was no bilateral difference in angle size. In blind trials, 83.2% of petrous bones were assigned to the correct sex. We also tested the lateral angle method against an...
van Goor, H; Stuiver, B
1998-01-01
Due to a lack of pertinent data, little is known about nonresponse in substantive, generally "dependent" variables and its consequences. However, in a study on policy performance of Dutch municipalities, we were fortunately able to gather performance data fur respondents and nonrespondents from inde
Neutrino Mixing Angles in Sequential Dominance to NLO and NNLO
Antusch, S; King, S F
2010-01-01
Neutrinos with hierarchical masses and two large mixing angles may naturally originate from sequential dominance (SD). Within this framework we present analytic expressions for the neutrino mixing angles including the next-to-leading order (NLO) and next-to-next-to-leading order (NNLO) corrections arising from the second lightest and lightest neutrino masses. The analytic results for neutrino mixing angles in SD presented here, including the NLO and NNLO corrections, are applicable to a wide class of models and may provide useful insights when confronting the models with data from high precision neutrino experiments. We also point out that for special cases of SD corresponding to form dominance (FD) the NLO and NNLO corrections both vanish. For example we study tri-bimaximal (TB) mixing via constrained sequential dominance (CSD) which involves only a NNLO correction and tri-bimaximal-reactor (TBR) mixing via partially constrained sequential dominance (PCSD) which involves a NLO correction suppressed by the sm...
Are lepton flavor mixings in the democratic mass matrix stable against quantum corrections?
Haba, N; Okamura, N; Suzuki, T
2000-01-01
We investigate whether the lepton flavor mixing angles in the so-called democratic type of mass matrix are stable against quantum corrections or not in the minimal supersymmetric standard model with dimension five operator which induces neutrino mass matrix. By taking simple breaking patterns of $S_3{}_L \\times S_3{}_R$ or $O(3)_L \\times O(3)_R$ flavor symmetries and the scale where democratic textures are induced as $O(10^{13})$ GeV, we find that the stability of the lepton flavor mixing angles in the democratic type of mass matrix against quantum corrections depends on the solar neutrino solutions. The maximal flavor mixing of the vacuum oscillation solution is spoiled by the quantum corrections in the experimental allowed region of $\\tan \\beta$. The large angle MSW solution is spoiled by the quantum corrections in the region of $\\tan \\beta > 10$. The condition of $\\tan \\beta \\leq 10$ is needed in order to obtain the suitable mass squared difference of the small angle MSW solution. These strong constraints ...
PROCEEDINGS OF THE WORKSHOP ON LHC INTERACTION REGION CORRECTION SYSTEMS
International Nuclear Information System (INIS)
The Workshop on LHC Interaction Region Correction Systems was held at Brookhaven National Laboratory, Upton, New York, on 6 and 7 May 1999. It was attended by 25 participants from 5 institutions. The performance of the Large Hadron Collider (LHC) at collision energy is limited by the field quality of the interaction region quadrupoles and dipoles. In three sessions the workshop addressed the field quality of the these magnets, reviewed the principles and efficiency of global and local correction schemes and finalized a corrector layout. The session on Field Quality Issues, chaired by J. Strait (FNAL), discussed the progress made by KEK and FNAL in achieving the best possible field quality in the interaction region quadrupoles. Results of simulation studies were presented that assess the effects of magnetic field errors with simulation studies. Attention was given to the uncertainties in predicting and measuring field errors. The session on Global Correction, chaired by J.-P. Koutchouk (CERN), considered methods of reducing the nonlinear detuning or resonance driving terms in the accelerator one-turn map by either sorting or correcting. The session also discussed the crossing angle dependence of the dynamic aperture and operational experience from LEP. The session on Local Correction, chaired by T. Taylor (CERN), discussed the location, strength and effectiveness of multipole correctors in the interaction regions for both proton and heavy ion operation. Discussions were based on technical feasibility considerations and dynamic aperture requirements. The work on linear corrections in the interaction regions was reviewed
PROCEEDINGS OF THE WORKSHOP ON LHC INTERACTION REGION CORRECTION SYSTEMS
Energy Technology Data Exchange (ETDEWEB)
FISCHER,W.; WEI,J.
1999-09-02
The Workshop on LHC Interaction Region Correction Systems was held at Brookhaven National Laboratory, Upton, New York, on 6 and 7 May 1999. It was attended by 25 participants from 5 institutions. The performance of the Large Hadron Collider (LHC) at collision energy is limited by the field quality of the interaction region quadrupoles and dipoles. In three sessions the workshop addressed the field quality of the these magnets, reviewed the principles and efficiency of global and local correction schemes and finalized a corrector layout. The session on Field Quality Issues, chaired by J. Strait (FNAL), discussed the progress made by KEK and FNAL in achieving the best possible field quality in the interaction region quadrupoles. Results of simulation studies were presented that assess the effects of magnetic field errors with simulation studies. Attention was given to the uncertainties in predicting and measuring field errors. The session on Global Correction, chaired by J.-P. Koutchouk (CERN), considered methods of reducing the nonlinear detuning or resonance driving terms in the accelerator one-turn map by either sorting or correcting. The session also discussed the crossing angle dependence of the dynamic aperture and operational experience from LEP. The session on Local Correction, chaired by T. Taylor (CERN), discussed the location, strength and effectiveness of multipole correctors in the interaction regions for both proton and heavy ion operation. Discussions were based on technical feasibility considerations and dynamic aperture requirements. The work on linear corrections in the interaction regions was reviewed.
Phase angle measurement techniques
Energy Technology Data Exchange (ETDEWEB)
Madge, R.; Fischer, D.
1996-01-01
Real-time measure of the power transfer across a transmission line was discussed. Phase angle measurement techniques, algorithms and applications relevant to power utilities were assessed. Phase-based applications compute the voltage angle difference between two stations, thereby allowing for power transfer calculations and power system control applications. A list of phase angle measurement applications was provided. It includes frequency measurement, state estimation, adaptive relaying, power system control, system restoration, real power flow monitoring and stability assessment, reactive power requirements monitoring, HVDC modulation, subsynchronous resonance, sequence of event recording, and loss reduction and fault location. The optimum timing requirement was determined for each application. Among the timing systems available today, the Global Positioning System (GPS), supported by powerful computers and other custom hardware, is the only tool that can provide the accuracy and coverage needed by today`s power system applications. Commercially available equipment for phase angle measurements was also reviewed. 30 refs., 32 tabs., 5 figs.
Mueller, Christian; Torrez, Daniel; Braag, Sofia; Martino, Ashley; Clarke, Tracy; Campbell-Thompson, Martha; Flotte, Terence R
2008-01-01
Recently, we have developed a model of airway inflammation in a CFTR knockout mouse utilizing Aspergillus fumigatus crude protein extract (Af-cpe) to mimic allergic bronchopulmonary aspergillosis (ABPA) 1, an unusual IgE-mediated hypersensitivity syndrome seen in up to 15% of cystic fibrosis (CF) patients and rarely elsewhere. We hypothesized that replacement of CFTR via targeted gene delivery to airway epithelium would correct aberrant epithelial cytokine signaling and ameliorate the ABPA phenotype in CFTR-deficient (CFTR 489X - /-, FABP-hCFTR + / +) mice. CFTR knockout mice underwent intra-tracheal (IT) delivery of recombinant adeno-associated virus serotype 5 (rAAV5Delta-264CFTR) or rAAV5-GFP at 2.58 x 10(12) viral genomes/mouse. All mice were then sensitized with two serial injections (200 microg) of crude Af antigen via the intra-peritoneal (IP) route. Untreated mice were sensitized without virus exposure. Challenges were performed 2 weeks after final sensitization, using a 0.25% solution containing Aspergillus fumigatus crude protein extract delivered by inhalation on three consecutive days. The rAAV5Delta-264CFTR-treated mice had lower total serum IgE levels (172513 ng/ml +/- 1312) than rAAV5-GFP controls (26 892 ng/ml +/- 3715) (p = 0.037) and non-treated, sensitized controls (24 816 +/- 4219 ng/ml). Serum IgG1 levels also were lower in mice receiving the CFTR vector. Interestingly, splenocytes from rAAV5Delta-264CFTR-treated mice secreted less IL-13, INFg, TNFa, RANTES and GM-CSF after ConA stimulation. Gene therapy with rAAV5Delta-264CFTR attenuated the hyper-IgE response in this reproducible CF mouse model of ABPA, with systemic effects also evident in the cytokine response of stimulated splenocytes. PMID:18023072
Angular dose dependency of MatriXX and its calibration
International Nuclear Information System (INIS)
Objective: To characterize angular dependency of MatriXX and develop a method for its calibration in order to verify treatment plan with original gantry angles. Methods: Absolute dose calibration was carried with thimble ionization chamber on the linear accelerator, so as to make sure 1 MU=1 cGy at the depth of maximum dose (dmax). A MatriXX was put into a Mutlicube phantom, and the ionization chamber matrix was calibrated with absolute dose. In order to determine a correction factor CF as a function of gantry angle θ, open beam fields of 10 cm×10 cm size were irradiated for gantry angles θ=0°-180° (every 5°) and every 1°for lateral angles θ in the range of 85°-95°. CF was defined as the ratio of the dose measured with ionization chamber and the dose from MatriXX. Results: Relatively large discrepancies in response to posterior VS, anterior fields for MatriXX detectors (up to 10%) were found during the experiment and relatively large variability of response as a function of gantry angle. The pass rate of treatment plan in lateral beams was lower than that of other beams. The isodose distribution of corrected MatriXX matched well with the outcome from the treatment planning system. Conclusions: The angular dose dependency of MatriXX must be considered when it is used to verify the treatment plan with original gantry angles. (authors)
Analysis of factors affecting angle ANB.
Hussels, W; Nanda, R S
1984-05-01
Cephalometric analyses based on angular and linear measurements have obvious fallacies, which have been discussed in detail by Moyers and Bookstein. However, the clinical application of such an analysis by the orthodontic profession in treatment planning is widely accepted. Variations of angle ANB are commonly used to determine relative jaw relationships in most of the cephalometric evaluations. Several authors, including points A and B influences angle ANB, as does rotational growth of the upper and lower jaws. In addition, the authors point out that growth in a vertical direction (distance N to B) and an increase of the dental height (distance A to B) may contribute to changes in angle ANB. For a Class I relation (Wits = 0 mm), a mathematical formula has been developed which enables the authors to study the geometric influence of angle ANB caused by the following four effects: (1) rotation of the jaws and/or occlusal plane relative to the anterior cranial base; (2) anteroposterior position of N relative to point B, (3) vertical growth (distance N to B); (4) increase in dental height (distance A to B). It was observed that, contrary to the common belief that an ANB angle of 2 +/- 3.0 degrees is considered normal for a skeletal Class I relation, the calculated values of angle ANB will vary widely with changes in these four controlling factors under the same skeletal Class I conditions (Wits = 0 mm). Therefore, in a case under consideration, angle ANB must be corrected for these geometric effects in order to get a proper perspective of the skeletal discrepancy. This is facilitated by comparing the measured ANB angle with the corresponding ANB angle calculated by a formula for a Class I relationship. The corresponding calculated angle ANB can be taken from the tables which are based upon the formula using the same values for SNB, omega (angle between occlusal plane and anterior cranial base), b (which is distance N to B) and a (dental height measured as perpendicular
Wear, Keith; Liu, Yunbo; Gammell, Paul M; Maruvada, Subha; Harris, Gerald R
2015-01-01
Nonlinear acoustic signals contain significant energy at many harmonic frequencies. For many applications, the sensitivity (frequency response) of a hydrophone will not be uniform over such a broad spectrum. In a continuation of a previous investigation involving deconvolution methodology, deconvolution (implemented in the frequency domain as an inverse filter computed from frequency-dependent hydrophone sensitivity) was investigated for improvement of accuracy and precision of nonlinear acoustic output measurements. Timedelay spectrometry was used to measure complex sensitivities for 6 fiber-optic hydrophones. The hydrophones were then used to measure a pressure wave with rich harmonic content. Spectral asymmetry between compressional and rarefactional segments was exploited to design filters used in conjunction with deconvolution. Complex deconvolution reduced mean bias (for 6 fiber-optic hydrophones) from 163% to 24% for peak compressional pressure (p+), from 113% to 15% for peak rarefactional pressure (p-), and from 126% to 29% for pulse intensity integral (PII). Complex deconvolution reduced mean coefficient of variation (COV) (for 6 fiber optic hydrophones) from 18% to 11% (p+), 53% to 11% (p-), and 20% to 16% (PII). Deconvolution based on sensitivity magnitude or the minimum phase model also resulted in significant reductions in mean bias and COV of acoustic output parameters but was less effective than direct complex deconvolution for p+ and p-. Therefore, deconvolution with appropriate filtering facilitates reliable nonlinear acoustic output measurements using hydrophones with frequency-dependent sensitivity. PMID:25585399
Directory of Open Access Journals (Sweden)
Cleber Antonio Jansen Paccola
2010-01-01
Full Text Available É apresentado o planejamento pré-operatório passo a passo da osteotomia de abertura supracondiliana do fêmur para a correção precisa do eixo de carga do membro inferior usando um implante de ângulo fixo (placa lâmina AO 95º. Também é apresentada a técnica cirúrgica e a utilização de enxerto ósseo do próprio local para o preenchimento da falha.The pre-operative planning is presented in a step by step fashion and the surgical technique of the lateral open wedge supracondylar femoral osteotomy for correction of the valgus knee using a fixed angle implant (95º AO angled blade plate. A surgical method for filling in the defect using an autologous bone graft is also presented.
Tounsi, R.; Markiewicz, E.; Haugou, G.; Chaari, F.; Zouari, B.
2016-05-01
The combined effect of the loading angle (ψ) and the in-plane orientation angle (β) on the dynamic enhancement of aluminium alloy honeycombs is investigated. Experimental results are analysed on the crushing surfaces (initial peak and average crushing forces). A significant effect of the loading angle is reported. The dynamic enhancement rate depends on the loading angle until a critical loading angle (ψcritical). Beyond, a negative dynamic enhancement rate is observed. Concerning the in-plane orientation angle β effect, it depends on the loading angle ψ under quasi-static conditions. Under dynamic conditions, a significant effect is reported independently of the loading angle ψ. Therefore, the dynamic enhancement rate depends on the combined effects of ψ and β angles. A global analysis of the buckling mechanisms allowed us to explain the combined effect of ψ and β angles on the initial peak force. The collapse mechanisms analysis explain the negative dynamic enhancement rate for large loading angles.
Foreign Body Embedded in Anterior Chamber Angle
Shmuel Graffi; Beatrice Tiosano; Ran Ben Cnaan; Jonathan Bahir; Modi Naftali
2012-01-01
Introduction. We present a case of a metallic foreign body embedded in the anterior chamber angle. After standing in close proximity to a construction worker breaking a tile, a 26-year-old woman using soft contact lens for the correction of mild myopia presented to emergency department for evaluation of a foreign body sensation of her right eye. Methods and Results. Diagnosis was confirmed by gonioscopic examination and a noncontrast CT scan of head and orbits. The foreign body was removed by...
Critical Assessment of Correction Methods for Fisheye Lens Distortion
Liu, Y.; Tian, C.; Huang, Y.
2016-06-01
A fisheye lens is widely used to create a wide panoramic or hemispherical image. It is an ultra wide-angle lens that produces strong visual distortion. The distortion modeling and estimation of the fisheye lens are the crucial step for fisheye lens calibration and image rectification in computer vision and close-range photography. There are two kinds of distortion: radial and tangential distortion. Radial distortion is large for fisheye imaging and critical for the subsequent image processing. Although many researchers have developed calibration algorithms of radial distortion of fisheye lens, quantitative evaluation of the correction performance has remained a challenge. This is the first paper that intuitively and objectively evaluates the performance of five different calibration algorithms. Upto- date research on fisheye lens calibration is comprehensively reviewed to identify the research need. To differentiate their performance in terms of precision and ease-using, five methods are then tested using a diverse set of actual images of the checkerboard that are taken at Wuhan University, China under varying lighting conditions, shadows, and shooting angles. The method of rational function model, which was generally used for wide-angle lens correction, outperforms the other methods. However, the one parameter division model is easy for practical use without compromising too much the precision. The reason is that it depends on the linear structure in the image and requires no preceding calibration. It is a tradeoff between correction precision and ease-using. By critically assessing the strengths and limitations of the existing algorithms, the paper provides valuable insight and guideline for future practice and algorithm development that are important for fisheye lens calibration. It is promising for the optimal design of lens correction models that are suitable for the millions of portable imaging devices.
Two-loop electroweak fermionic corrections to sin2θbantibeff
International Nuclear Information System (INIS)
We present the first calculation of the two-loop electroweak fermionic correction to the flavour-dependent effective weak-mixing angle for bottom quarks, sin2Θbantibeff. For the evaluation of the missing two-loop vertex diagrams, two methods are employed, one based on a semi-numerical Bernstein-Tkachov algorithm and the second on asymptotic expansions in the large top-quark mass. A third method based on dispersion relations is used for checking the basic loop integrals. We find that for small Higgs-boson mass values, MH ∝100 GeV, the correction is sizable, of order O(10-4). (orig.)
DEFF Research Database (Denmark)
Miles, James Edward; Frederiksen, Jane V.; Jensen, Bente Rona;
2012-01-01
: Pelvic limbs from red foxes (Vulpes vulpes). METHODS: Q angles were measured on hip dysplasia (HD) and whole limb (WL) view radiographs of each limb between the acetabular rim, mid-point (Q1: patellar center, Q2: femoral trochlea), and tibial tuberosity. Errors of 0.5-2.0 mm at measurement landmarks...
1994-01-01
The Large Angle Magnetic Suspension Test Fixture (LAMSTF) is a 5 degree-of -freedom repulsive force magnetic suspension system designed to study the control of objects over large magnetic gaps. A digital control algorithm uses 6 sets of laser-sheet sensors and 5 control coils to position a cylinder 3' above the plane of electromagnetics
DEFF Research Database (Denmark)
Morgan, Jeannie; Lynnerup, Niels; Hoppa, R.D.
2013-01-01
measurements taken from computed tomography (CT) scans. Previous reports have observed that the lateral angle size in females is significantly larger than in males. The method was applied to an independent series of 77 postmortem CT scans (42 males, 35 females) to validate its accuracy and reliability. The...
Optical fibre angle sensor used in MEMS
International Nuclear Information System (INIS)
There is a need for displacement and angle measurements in many movable MEMS structures. The use of fibre optical sensors helps to measure micrometre displacements and small rotation angles. Advantages of this type of transducers are their simple design, high precision of processing, low costs and ability of a non-contact measurement. The study shows an analysis of a fibre-optic intensity sensor used for MEMS movable structure rotation angle measurement. An intensity of the light in the photodetector is basically dependent on a distance between a reflecting surface and a head surface of the fibre transmitting arm, and the deflection angle. Experimental tests were made for PMMA 980/1000 plastic fibres, ΘNA=33°. The study shows both analytical and practical results. It proves that calculated and experimental characteristics for the analysed transducers are similar.
Confinement Correction to Mercury Intrusion Capillary Pressure of Shale Nanopores
Wang, Sen; Javadpour, Farzam; Feng, Qihong
2016-02-01
We optimized potential parameters in a molecular dynamics model to reproduce the experimental contact angle of a macroscopic mercury droplet on graphite. With the tuned potential, we studied the effects of pore size, geometry, and temperature on the wetting of mercury droplets confined in organic-rich shale nanopores. The contact angle of mercury in a circular pore increases exponentially as pore size decreases. In conjunction with the curvature-dependent surface tension of liquid droplets predicted from a theoretical model, we proposed a technique to correct the common interpretation procedure of mercury intrusion capillary pressure (MICP) measurement for nanoporous material such as shale. Considering the variation of contact angle and surface tension with pore size improves the agreement between MICP and adsorption-derived pore size distribution, especially for pores having a radius smaller than 5 nm. The relative error produced in ignoring these effects could be as high as 44%—samples that contain smaller pores deviate more. We also explored the impacts of pore size and temperature on the surface tension and contact angle of water/vapor and oil/gas systems, by which the capillary pressure of water/oil/gas in shale can be obtained from MICP. This information is fundamental to understanding multiphase flow behavior in shale systems.
Confinement Correction to Mercury Intrusion Capillary Pressure of Shale Nanopores
Wang, Sen; Javadpour, Farzam; Feng, Qihong
2016-01-01
We optimized potential parameters in a molecular dynamics model to reproduce the experimental contact angle of a macroscopic mercury droplet on graphite. With the tuned potential, we studied the effects of pore size, geometry, and temperature on the wetting of mercury droplets confined in organic-rich shale nanopores. The contact angle of mercury in a circular pore increases exponentially as pore size decreases. In conjunction with the curvature-dependent surface tension of liquid droplets predicted from a theoretical model, we proposed a technique to correct the common interpretation procedure of mercury intrusion capillary pressure (MICP) measurement for nanoporous material such as shale. Considering the variation of contact angle and surface tension with pore size improves the agreement between MICP and adsorption-derived pore size distribution, especially for pores having a radius smaller than 5 nm. The relative error produced in ignoring these effects could be as high as 44%—samples that contain smaller pores deviate more. We also explored the impacts of pore size and temperature on the surface tension and contact angle of water/vapor and oil/gas systems, by which the capillary pressure of water/oil/gas in shale can be obtained from MICP. This information is fundamental to understanding multiphase flow behavior in shale systems. PMID:26832445
Confinement Correction to Mercury Intrusion Capillary Pressure of Shale Nanopores.
Wang, Sen; Javadpour, Farzam; Feng, Qihong
2016-01-01
We optimized potential parameters in a molecular dynamics model to reproduce the experimental contact angle of a macroscopic mercury droplet on graphite. With the tuned potential, we studied the effects of pore size, geometry, and temperature on the wetting of mercury droplets confined in organic-rich shale nanopores. The contact angle of mercury in a circular pore increases exponentially as pore size decreases. In conjunction with the curvature-dependent surface tension of liquid droplets predicted from a theoretical model, we proposed a technique to correct the common interpretation procedure of mercury intrusion capillary pressure (MICP) measurement for nanoporous material such as shale. Considering the variation of contact angle and surface tension with pore size improves the agreement between MICP and adsorption-derived pore size distribution, especially for pores having a radius smaller than 5 nm. The relative error produced in ignoring these effects could be as high as 44%--samples that contain smaller pores deviate more. We also explored the impacts of pore size and temperature on the surface tension and contact angle of water/vapor and oil/gas systems, by which the capillary pressure of water/oil/gas in shale can be obtained from MICP. This information is fundamental to understanding multiphase flow behavior in shale systems. PMID:26832445
Abelleira, J L; Bhat, C; Cornelis, K; De Maria, R; Fartoukh, S; Giachino, R; Holzer, E B; Lamont, M; Mastoridis, T; Macpherson, A; Papotti, G; Pieloni, T; Roncarolo, F; Roy, G; Salvachua, B; Valuch, D; Zimmermann, F; Ohmi, K
2012-01-01
Two high brightness bunches per beam were collided at injection energy with varying spectrometer strength in IP8 so that the corresponding Piwinski angle changed from about 1.2–1.3 to 0.2. One of the two bunches colliding in IP8 also collided in IPs 1 and 5, increasing its tune spread. A Piwinski angle of 1.2 is the biggest value ever achieved in a hadron collider. The goal of this experiemnt had been to investigate the influence of this parameter on the luminosity lifetime, beam lifetime and emittance growth rate. Due to technical problems and unavailability of luminosity signals from CMS this goal was only partially accomplished.
Nundy, Surajit; Lotto, Beau; Coppola, David; Shimpi, Amita; Purves, Dale
2000-01-01
Although it has long been apparent that observers tend to overestimate the magnitude of acute angles and underestimate obtuse ones, there is no consensus about why such distortions are seen. Geometrical modeling combined with psychophysical testing of human subjects indicates that these misperceptions are the result of an empirical strategy that resolves the inherent ambiguity of angular stimuli by generating percepts of the past significance of the stimulus rather than the geometry of its re...
Angle states in quantum mechanics
de la Torre, A. C.; Iguain, J. L.
1998-12-01
Angle states and angle operators are defined for a system with arbitrary angular momentum. They provide a reasonable formalization of the concept of angle provided that we accept that the angular orientation is quantized. The angle operator is the generator of boosts in angular momentum and is, almost everywhere, linearly related to the logarithm of the shift operator. Angle states for fermions and bosons behave differently under parity transformation.
Self-correction coil: operation mechanism of self-correction coil
International Nuclear Information System (INIS)
We discuss here the operation mechanism of self-correction coil with a simple model. At the first stage, for the ideal self-correction coil case we calculate the self-inductance L of self-correction coil, the mutual inductance M between the error field coil and the self-correction coil, and using the model the induced curent in the self-correction coil by the external magnetic error field and induced magnetic field by the self-correction coil. And at the second stage, we extend this calculation method to non-ideal self-correction coil case, there we realize that the wire distribution of self-correction coil is important to get the high enough self-correction effect. For measure of completeness of self-correction effect, we introduce the efficiency eta of self-correction coil by the ratio of induced magnetic field by the self-correction coil and error field. As for the examples, we calculate L, M and eta for two cases; one is a single block approximation of self-correction coil winding and the other is a two block approximation case. By choosing the adequate angles of self-correction coil winding, we can get about 98% efficiency for single block approximation case and 99.8% for two block approximation case. This means that by using the self-correction coil we can improve the field quality about two orders
Self-correction coil: Operation mechanism of self-correction coil
Hosoyama, K.
1983-06-01
The operation mechanism of self-correction coil is extended with a simple model. For the ideal self-correction coil case, The self-inductance L of the self-correction coil is calculated. This calculation method is extended to a non-ideal self-correction coil case. For measure of completeness of self-correction coil is measured by the ratio of induced magnetic field by the self-correction coil and error field. Examples are L, M and N calculated for two cases; one is a single block approximation of self-correction coil winding and the other is a two block approximation case. By choosing the adequate angles of self-correction coil winding, one can get about 98% efficiency for single block approximation case and 99.8% for two block approximation case.
Institute of Scientific and Technical Information of China (English)
王磊; 祁荣; 康全明; 刘利民; 陈华; 王凯
2014-01-01
BACKGROUND:Simple spinal decompression for lumbar degeneration-induced lumbar scoliosis spinal stenosis is difficult to obtain long-term efficacy. Because simple decompression is considered an iatrogenic lumbar instability, and can aggravate lumbar deformity. Posterior lumbar pedicle screw fixation combined with decompression and fusion obtained good curative effects in patients. OBJECTIVE:To investigate the clinical efficacy of posterior decompression, internal fixation, and bone graft fusion with posterior pedicle screw system in the treatment of degenerative lumbar scoliosis with stenosis. METHODA retrospective analysis was performed in 18 patients with degenerative lumbar scoliosis with stenosis who received surgical treatment from February 2009 to November 2012. These patients consisted of 6 males and 12 females, with a mean age of 62.2 years (range, 48-80 years). They had lumbar scoliosis with a mean Cobb angle of 28.6° and underwent posterior decompression, internal fixation, and bone graft fusion. RESULTS AND CONCLUSION:Al the 18 patients achieved satisfactory fol ow-up. The mean fol ow-up was 22 months. Al patients were satisfied with treatment outcomes and had improved quality of life. The mean correction angle was 13.7° (range, 6.0°-28.4°) after operation. There was no failure of internal fixation, and no infected cases were found. These data inducated that posterior decompression, internal fixation, and bone graft fusion is one of the effective methods for treating degenerative lumbar scoliosis with stenosis.%背景：腰椎退变导致腰椎侧凸性椎管狭窄患者单纯椎管减压难以获得长期疗效，因为单纯减压被视为一种医源性的腰椎失稳，从而加重腰椎畸形，选用腰椎后路椎弓根螺钉固定，结合减压植骨融合治疗此类患者取得了良好的疗效。 目的：评价采用后路椎弓根螺钉系统后路减压、内固定、植骨融合治疗退行性腰椎侧凸性椎管狭窄的临
Cerebellopontine angle Hodgkin's disease
International Nuclear Information System (INIS)
Intracranial Hodgkin's disease is a rare site of involvement, and even more rare is its presentation as a cerebellopontine angle mass. It can be difficult to diagnose especially when recurrent tumors occur because both CT and lumbar puncture have been shown to have a relatively low yield. Gadolinium-enhanced MRI is more sensitive. It is concluded that while the imaging findings can be non-specific, the rapid response to therapy (steroids) may provide a clue to diagnosis. Copyright (1999) Blackwell Science Pty Ltd
Radiative corrections to Bose condensation
Energy Technology Data Exchange (ETDEWEB)
Gonzalez, A. (Academia de Ciencias de Cuba, La Habana. Inst. de Matematica, Cibernetica y Computacion)
1985-04-01
The Bose condensation of the scalar field in a theory behaving in the Coleman-Weinberg mode is considered. The effective potential of the model is computed within the semiclassical approximation in a dimensional regularization scheme. Radiative corrections are shown to introduce certain ..mu..-dependent ultraviolet divergences in the effective potential coming from the Many-Particle theory. The weight of radiative corrections in the dynamics of the system is strongly modified by the charge density.
Indian Academy of Sciences (India)
Mrinal Kumar Das; Mahadev Patgiri; N Nimai Singh
2005-12-01
We briefly outline the two popular approaches on radiative corrections to neutrino masses and mixing angles, and then carry out a detailed numerical analysis for a consistency check between them in MSSM. We find that the two approaches are nearly consistent with a discrepancy factor of 4.2% with running vacuum expectation value (VEV) (13% for scale-independent VEV) in mass eigenvalues at low-energy scale but the predictions on mixing angles are almost consistent. We check the stability of the three types of neutrino models, i.e., hierarchical, inverted hierarchical and degenerate models, under radiative corrections, using both approaches, and find consistent conclusions. The neutrino mass models which are found to be stable under radiative corrections in MSSM are the normal hierarchical model and the inverted hierarchical model with opposite CP parity. We also carry out numerical analysis on some important conjectures related to radiative corrections in the MSSM, viz., radiative magnification of solar and atmospheric mixings in the case of nearly degenerate model having same CP parity (MPR conjecture) and radiative generation of solar mass scale in exactly two-fold degenerate model with opposite CP parity and non-zero 3 (JM conjecture). We observe certain exceptions to these conjectures. We find a new result that both solar mass scale and 3 can be generated through radiative corrections at low energy scale. Finally the effect of scale-dependent vacuum expectation value in neutrino mass renormalisation is discussed.
Holographic thermalization with Weyl corrections
Dey, Anshuman; Mahapatra, Subhash; Sarkar, Tapobrata
2016-01-01
We consider holographic thermalization in the presence of a Weyl correction in five dimensional AdS space. We first obtain the Weyl corrected black brane solution perturbatively, up to first order in the coupling. The corresponding AdS-Vaidya like solution is then constructed. This is then used to numerically analyze the time dependence of the two point correlation functions and the expectation values of rectangular Wilson loops in the boundary field theory, and we discuss how the Weyl correction can modify the thermalization time scales in the dual field theory. In this context, the subtle interplay between the Weyl coupling constant and the chemical potential is studied in detail.
Variable angle correlation spectroscopy
International Nuclear Information System (INIS)
In this dissertation, a novel nuclear magnetic resonance (NMR) technique, variable angle correlation spectroscopy (VACSY) is described and demonstrated with 13C nuclei in rapidly rotating samples. These experiments focus on one of the basic problems in solid state NMR: how to extract the wealth of information contained in the anisotropic component of the NMR signal while still maintaining spectral resolution. Analysis of the anisotropic spectral patterns from poly-crystalline systems reveal information concerning molecular structure and dynamics, yet in all but the simplest of systems, the overlap of spectral patterns from chemically distinct sites renders the spectral analysis difficult if not impossible. One solution to this problem is to perform multi-dimensional experiments where the high-resolution, isotropic spectrum in one dimension is correlated with the anisotropic spectral patterns in the other dimensions. The VACSY technique incorporates the angle between the spinner axis and the static magnetic field as an experimental parameter that may be incremented during the course of the experiment to help correlate the isotropic and anisotropic components of the spectrum. The two-dimensional version of the VACSY experiments is used to extract the chemical shift anisotropy tensor values from multi-site organic molecules, study molecular dynamics in the intermediate time regime, and to examine the ordering properties of partially oriented samples. The VACSY technique is then extended to three-dimensional experiments to study slow molecular reorientations in a multi-site polymer system
Variable angle correlation spectroscopy
Energy Technology Data Exchange (ETDEWEB)
Lee, Y K [Univ. of California, Berkeley, CA (United States)
1994-05-01
In this dissertation, a novel nuclear magnetic resonance (NMR) technique, variable angle correlation spectroscopy (VACSY) is described and demonstrated with {sup 13}C nuclei in rapidly rotating samples. These experiments focus on one of the basic problems in solid state NMR: how to extract the wealth of information contained in the anisotropic component of the NMR signal while still maintaining spectral resolution. Analysis of the anisotropic spectral patterns from poly-crystalline systems reveal information concerning molecular structure and dynamics, yet in all but the simplest of systems, the overlap of spectral patterns from chemically distinct sites renders the spectral analysis difficult if not impossible. One solution to this problem is to perform multi-dimensional experiments where the high-resolution, isotropic spectrum in one dimension is correlated with the anisotropic spectral patterns in the other dimensions. The VACSY technique incorporates the angle between the spinner axis and the static magnetic field as an experimental parameter that may be incremented during the course of the experiment to help correlate the isotropic and anisotropic components of the spectrum. The two-dimensional version of the VACSY experiments is used to extract the chemical shift anisotropy tensor values from multi-site organic molecules, study molecular dynamics in the intermediate time regime, and to examine the ordering properties of partially oriented samples. The VACSY technique is then extended to three-dimensional experiments to study slow molecular reorientations in a multi-site polymer system.
International Nuclear Information System (INIS)
The authors have made the first measurement of the double-inclusive B/(bar B) energy distribution in e+e- annihilations, using a sample of 400,000 hadronic Z0-decay events recorded in the SLD experiment at SLAC between 1996 and 1998. The small and stable SLC beam spot and the CCD-based vertex detector were used to reconstruct B/(bar B)-decay vertices with high efficiency and purity, and to provide precise measurements of the kinematic quantities used to calculate the B energies in this novel technique. They measured the B/(bar B) energies with good efficiency and resolution over the full kinematic range. They measured moments of the scaled energies of the B and (bar B) hadrons vs. the opening angle between them. By comparing these results with perturbative QCD predictions they tested the ansatz of factorization in heavy-quark production. A recent next-to-leading order calculation reproduces the data
Abe, K
2004-01-01
We have made the first measurement of the double-inclusive B/Bbar energy distribution in e+e- annihilations, using a sample of 400,000 hadronic Z0 decay events recorded in the SLD experiment at SLAC between 1996 and 1998. The small and stable SLC beam spot and the CCD-based vertex detector were used to reconstruct B/Bbar decay vertices with high efficiency and purity, and to provide measurements of the kinematic quantities used to calculate the B energies in this novel technique. We measured the B/Bbar energies with good efficiency and resolution over the full kinematic range. We measured moments of the scaled energies of the B and Bbar hadrons vs. the opening angle between them. By comparing these results with perturbative QCD predictions we tested the ansatz of factorisation in heavy-quark production. A recent next-to-leading order calculation reproduces the data.
International Nuclear Information System (INIS)
We have made the first measurement of the double-inclusive B/B energy distribution in e+e- annihilations, using a sample of 400,000 hadronic Z0-decay events recorded in the SLD experiment at SLAC between 1996 and 1998. The small and stable SLC beam spot and the CCD-based vertex detector were used to reconstruct B/B-decay vertices with high efficiency and purity, and to provide precise measurements of the kinematic quantities used to calculate the B energies in this novel technique. We measured the B/B energies with good efficiency and resolution over the full kinematic range. We measured moments of the scaled energies of the B and B hadrons vs. the opening angle between them. By comparing these results with perturbative QCD predictions we tested the ansatz of factorisation in heavy-quark production. A recent next-to-leading order calculation reproduces the data. (orig.)
Institute of Scientific and Technical Information of China (English)
李震宇; 杨军; 梁毅; 邢孟道
2015-01-01
斜视成像是弹载合成孔径雷达（Synthetic Aperture Radar ，SAR）的一种重要工作模式，从实际应用出发，弹载 SAR 为实现快视成像常采用子孔径处理。由于在大斜视模式下，距离方位严重耦合，常规算法成像处理的第1步是采用时域校正距离走动的方法来消除距离方位的耦合，这会带来方位相位随方位位置空变问题，造成方位无法统一处理，影响方位聚焦深度。文中详细分析了弹载 SAR 大前斜瞬时斜距模型，针对子孔径数据，提出一种基于高次相位滤波的方位空变校正新方法，实现方位统一聚焦处理。点目标仿真数据处理验证了文中所提方法的有效性和实用性。%Squinted imaging is one of the most important modes in the missile‐borne synthetic aperture radar ( SAR) . Usually , from the view of practical applications , the missile‐borne SAR adopts subaperture processing in order to implement quick look imaging . In the highly squint mode , the echo signal couples greatly between range and azimuth , so traditional algorithms perform the linear range walk correction in the azimuth time domain firstly to mitigate greatly the range‐azimuth coupling , which causes the problem of position dependent azimuth phase , resulting in the azimuth uniform processing disabled and impacting the azimuth depth of focus (DOF) . Based on the deep analysis of the instantaneous slant range model in the highly squint missile‐borne SAR , this paper proposes high‐order phase filtering to correct azimuth‐dependence for implementing the identical azimuth‐focusing processing . Simulation results validate the effectiveness of the proposed algorithm .
Santocchia, Attilio
2009-01-01
Many physics measurements in CMS will rely on the precise reconstruction of Jets. Correction of the raw jet energy measured by the CMS detector will be a fundamental step for most of the analysis where hadron activity is investigated. Jet correction plans in CMS have been widely studied for different conditions: at stat-up simulation tuned on test-beam data will be used. Then data-driven methods will be available and finally, simulation tuned on collision data will give us the ultimate procedure for calculating jet corrections. Jet transverse energy is corrected first for pile-up and noise offset; correction for the response of the calorimeter as a function of jet pseudorapidity relative to the barrel comes afterwards and correction for the absolute response as a function of transverse momentum in the barrel is the final standard sub-correction applied. Other effects like flavour and parton correction will be optionally applied on the Jet $E_T$ depending on the measurement requests. In this paper w...
Angle performance on optima MDxt
International Nuclear Information System (INIS)
Angle control on medium current implanters is important due to the high angle-sensitivity of typical medium current implants, such as halo implants. On the Optima MDxt, beam-to-wafer angles are controlled in both the horizontal and vertical directions. In the horizontal direction, the beam angle is measured through six narrow slits, and any angle adjustment is made by electrostatically steering the beam, while cross-wafer beam parallelism is adjusted by changing the focus of the electrostatic parallelizing lens (P-lens). In the vertical direction, the beam angle is measured through a high aspect ratio mask, and any angle adjustment is made by slightly tilting the wafer platen prior to implant. A variety of tests were run to measure the accuracy and repeatability of Optima MDxt’s angle control. SIMS profiles of a high energy, channeling sensitive condition show both the cross-wafer angle uniformity, along with the small-angle resolution of the system. Angle repeatability was quantified by running a channeling sensitive implant as a regular monitor over a seven month period and measuring the sheet resistance-to-angle sensitivity. Even though crystal cut error was not controlled for in this case, when attributing all Rs variation to angle changes, the overall angle repeatability was measured as 0.16° (1σ). A separate angle repeatability test involved running a series of V-curves tests over a four month period using low crystal cut wafers selected from the same boule. The results of this test showed the angle repeatability to be <0.1° (1σ).
Pitch Perfect: How Fruit Flies Control their Body Pitch Angle
Whitehead, Samuel C; Canale, Luca; Cohen, Itai
2015-01-01
Flapping insect flight is a complex and beautiful phenomenon that relies on fast, active control mechanisms to counter aerodynamic instability. To directly investigate how freely-flying D. melanogaster control their body pitch angle against such instability, we perturb them using impulsive mechanical torques and film their corrective maneuvers with high-speed video. Combining experimental observations and numerical simulation, we find that flies correct for pitch deflections of up to 40 degrees in 29 +/- 8 ms by bilaterally modulating their wings' front-most stroke angle in a manner well-described by a linear proportional-integral (PI) controller. Flies initiate this corrective process after only 10 +/- 2 ms, indicating that pitch stabilization involves a fast reflex response. Remarkably, flies can also correct for very large-amplitude pitch perturbations--greater than 150 degrees--providing a regime in which to probe the limits of the linear-response framework. Together with previous studies regarding yaw an...
A note on the correction of ocean floor depths for sediment loading
Le Douaran, Sylvie; Parsons, Barry
1982-06-01
The measured physical properties of sediments recovered in a number of deep-sea drill holes in the North Atlantic have been used to derive expressions for the correction to basement depths required to account for loading by sediments. The average density and porosity over a given thickness of sediment show an approximate linear dependence on sediment thickness. This behavior can be explained as primarily the result of compaction. If the compaction of the sediments is neglected in correcting basement depths for sediment loading, errors of a few hundred meters in the corrected depths can be made. A sediment loading correction based on the observed variation of density with depth can give corrected depths to better than 100 m, with remaining uncertainties due to variability in sediment properties and rebound effects on the measured densities. A relation between sediment thickness and vertical travel time was obtained from sonic velocity measurements on samples from drill holes, sonobuoy wide-angle reflection experiments, and direct correlation of seismic reflectors with downhole lithology. The sediment loading correction can then be expressed directly in terms of the vertical travel time measured along seismic reflection profiles. The loading correction obtained here for the North Atlantic may not be applicable in areas with different sedimentary environments. When direct measurements of physical properties in drill holes are not available in such areas, it is shown that it is preferable to assume a compaction curve for the appropriate lithology rather than to use observed seismic velocities together with a velocity-density relationship.
Citalopram associated with acute angle-closure glaucoma: case report
Hassan Sabit; Thirumalai Srinivasa; Croos Robert; Davis Jane
2005-01-01
Abstract Background Acute angle-closure glaucoma is a rare complication in patients receiving anti-depressant treatment. In the following case, we report the development of acute angle closure glaucoma in a patient who overdosed on Citalopram, an antidepressant, and discuss the possible etiological mechanisms for the condition. Case presentation We report a 54 year old, Caucasian lady, with depression and alcohol dependence syndrome, who developed acute angle-closure glaucoma after an overdos...
Research of the Pressure Angle for Whole Cycloidal Gears
Institute of Scientific and Technical Information of China (English)
LIU Ling-tao; WANG Jian-hua
2011-01-01
The working profile of whole cycloidal gear is made up of epicycloid and hypocycloid entirely, according to the theory of meshing of gears and the properties of the cycloid, deals with the derivation of the pressure angle formula for the whole cycloidal gear in theory, and reveals changes of the pressure angle of whole cycloidal gear through examples, finds the application relationships between the pressure angle and other design parameters of the whole cycloidal gear, proves the possibility that the whole cycloidal gear can be used in internal parallel move gear mechanism, also provides theoretic fundament for designing internal parallel move whole cycloidal gear correctly.
Heterodyne Interferometer Angle Metrology
Hahn, Inseob; Weilert, Mark A.; Wang, Xu; Goullioud, Renaud
2010-01-01
A compact, high-resolution angle measurement instrument has been developed that is based on a heterodyne interferometer. The common-path heterodyne interferometer metrology is used to measure displacements of a reflective target surface. In the interferometer setup, an optical mask is used to sample the measurement laser beam reflecting back from a target surface. Angular rotations, around two orthogonal axes in a plane perpendicular to the measurement- beam propagation direction, are determined simultaneously from the relative displacement measurement of the target surface. The device is used in a tracking telescope system where pitch and yaw measurements of a flat mirror were simultaneously performed with a sensitivity of 0.1 nrad, per second, and a measuring range of 0.15 mrad at a working distance of an order of a meter. The nonlinearity of the device is also measured less than one percent over the measurement range.
Small angles Bhabha scattering: two loop approximation
International Nuclear Information System (INIS)
The elastic and inelastic cross sections for small angles e+e- scattering at high energies are considered. We prove that all the diagrams with two or more virtual photons in scattering channel may be omitted when calculating the radiative corrections with accuracy of the order 0.1%. It is the consequence of the generalized eikonal representation for elastic and inelastic amplitudes. We take into account the processes of single and double bremsstrahlung in the same and opposite directions and the pair production processes. Basing on this calculations we construct the combined formula for the inclusive scattering electron and positron cross section in terms of the structure functions. 15 refs.; 10 figs
Lam, C N C; Wu, R; Li, D; Hair, M L; Neumann, A W
2002-02-25
Two types of experiments were used to study the behavior of both advancing and receding contact angles, namely the dynamic one-cycle contact angle (DOCA) and the dynamic cycling contact angle (DCCA) experiments. For the preliminary study, DOCA measurements of different liquids on different solids were performed using an automated axisymmetric drop shape analysis-profile (ADSA-P). From these experimental results, four patterns of receding contact angle were observed: (1) time-dependent receding contact angle; (2) constant receding contact angle; (3) 'stick/slip'; (4) no receding contact angle. For the purpose of illustration, results from four different solid surfaces are shown. These solids are: FC-732-coated surface; poly(methyl methacrylate/n-butyl methacrylate) [P(MMA/nBMA)]; poly(lactic acid) (DL-PLA); and poly(lactic/glycolic acid) 50/50 (DL-PLGA 50/50). Since most of the surfaces in our studies exhibit time dependence in the receding contact angle, a more extended study was conducted using only FC-732-coated surfaces to better understand the possible causes of decreasing receding contact angle and contact angle hysteresis. Contact angle measurements of 21 liquids from two homologous series (i.e. n-alkanes and 1-alcohols) and octamethylcyclotetrasiloxane (OCMTS) on FC-732-coated surfaces were performed. It is apparent that the contact angle hysteresis decreases with the chain length of the liquid. It was found that the receding contact angle equals the advancing angle when the alkane molecules are infinitely large. These results strongly suggest that the chain length and size of the liquid molecule could contribute to contact angle hysteresis phenomena. Furthermore, DCCA measurements of six liquids from the two homologous series on FC-732-coated surfaces were performed. With these experimental results, one can construe that the time dependence of contact angle hysteresis on relatively smooth and homogeneous surfaces is mainly caused by liquid retention
Burrows, P N
2004-01-01
The have made the first measurement of the double-inclusive B/(bar B) energy distribution in e sup + e sup - annihilations, using a sample of 400,000 hadronic Z sup 0 -decay events recorded in the SLD experiment at SLAC between 1996 and 1998. The small and stable SLC beam spot and the CCD-based vertex detector were used to reconstruct B/(bar B)-decay vertices with high efficiency and purity, and to provide precise measurements of the kinematic quantities used to calculate the B energies in this novel technique. They measured the B/(bar B) energies with good efficiency and resolution over the full kinematic range. They measured moments of the scaled energies of the B and (bar B) hadrons vs. the opening angle between them. By comparing these results with perturbative QCD predictions they tested the ansatz of factorization in heavy-quark production. A recent next-to-leading order calculation reproduces the data.
International Nuclear Information System (INIS)
A new SN formulation has been developed which is effective at preserving the behavior of a coupled fine-mesh transport solver on a coarse, pin homogenized Cartesian mesh. The method uses angle- and energy-dependent correction factors and a modified formulation for the diamond difference equations, called corrected diamond difference (CDD). An extension of the CDD method from previous work includes a new cross section correction step. It is shown that the new CDD approach is equivalent in two-dimensional problems in theory and practice. The CDD method is then applied to several three-dimensional benchmark cases using one-way 2-D/3-D coupling, and is shown to provide more accurate results as compared to the previous CDD formulation and diamond difference alone. (author)
Czech Academy of Sciences Publication Activity Database
Aad, G.; Abajyan, T.; Abbott, B.; Böhm, Jan; Chudoba, Jiří; Gallus, Petr; Gunther, Jaroslav; Havránek, Miroslav; Hejbal, Jiří; Jakoubek, Tomáš; Kepka, Oldřich; Kupčo, Alexander; Kůs, Vlastimil; Lokajíček, Miloš; Lysák, Roman; Marčišovský, Michal; Mikeštíková, Marcela; Myška, Miroslav; Němeček, Stanislav; Růžička, Pavel; Schovancová, Jaroslava; Šícho, Petr; Staroba, Pavel; Svatoš, Michal; Taševský, Marek; Tic, Tomáš; Vrba, Václav; Zeman, Martin
2013-01-01
Roč. 111, č. 15 (2013), "152301-1"-"152301-19". ISSN 0031-9007 R&D Projects: GA MŠk(CZ) LG13009 Institutional support: RVO:68378271 Keywords : jet * transverse momentum * jet * quenching * path length * dependence * ATLAS * underlying event * CERN LHC Coll * elliptic flow Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 7.728, year: 2013
Hologram production and representation for corrected image
Jiao, Gui Chao; Zhang, Rui; Su, Xue Mei
2015-12-01
In this paper, a CCD sensor device is used to record the distorted homemade grid images which are taken by a wide angle camera. The distorted images are corrected by using methods of position calibration and correction of gray with vc++ 6.0 and opencv software. Holography graphes for the corrected pictures are produced. The clearly reproduced images are obtained where Fresnel algorithm is used in graph processing by reducing the object and reference light from Fresnel diffraction to delete zero-order part of the reproduced images. The investigation is useful in optical information processing and image encryption transmission.
Color corrected Fresnel lens for solar concentration
International Nuclear Information System (INIS)
A new linear convex Fresnel lens with its groove side down is described. The design philosophy is similar to the highly concentrating two focal Fresnel lens but including a correction for chromatic aberration. A solar concentration ratio as high as 80 is achieved. For wide acceptance angles the concentration nears the theoretical maximum. (author)
Drosg, Manfred
2016-01-01
Estimated cross sections for neutron production from triton bombardment of gold are deduced from measurements of triton interactions with gas targets that used gold as a triton beam stop material. Differential cross sections for production of neutrons from 5.97-, 7.47-, 10.45-, 16.41- and 19.14-MeV tritons on 197Au were evaluated. Corrections for the neutron interaction in gold, in the target structure and in the air of the flight path were obtained by means of a Monte Carlo technique. Uncorrelated scale uncertainties range from 24 to 41% whereas those of double differential cross sections range from 0.2 to 5%. Based on these cross section data, calculation of neutron yield at 0o from fully stopped tritons at 20.22 MeV agree with an independent measurement. Least-squares fits with a gamma distribution model indicate an anisotropy in the high energy portion of the neutron spectra. Legendre polynomial fits of differential cross sections are reported. All neutron cross section data are made available through the...
QCD corrections to tri-boson production
Lazopoulos, A; Petriello, F J; Lazopoulos, Achilleas; Melnikov, Kirill; Petriello, Frank
2007-01-01
We present a computation of the next-to-leading order QCD corrections to the production of three Z bosons at the LHC. We calculate these corrections using a completely numerical method that combines sector decomposition to extract infrared singularities with contour deformation of the Feynman parameter integrals to avoid internal loop thresholds. The NLO QCD corrections to pp -> ZZZ are approximately 50%, and are badly underestimated by the leading order scale dependence. However, the kinematic dependence of the corrections is minimal in phase space regions accessible at leading order.
Beyond the small-angle approximation for MBR anisotropy from seeds
International Nuclear Information System (INIS)
In this paper we give a general expression for the energy shift of massless particles traveling through the gravitational field of an arbitrary matter distribution as calculated in the weak field limit in an asymptotically flat space-time. It is not assumed that matter is nonrelativistic. We demonstrate the surprising result that if the matter is illuminated by a uniform brightness background that the brightness pattern observed at a given point in space-time (modulo a term dependent on the observer's velocity) depends only on the matter distribution on the observer's past light cone. These results apply directly to the cosmological MBR anisotropy pattern generated in the immediate vicinity of an object such as a cosmic string or global texture. We apply these results to cosmic strings, finding a correction to previously published results in the small-angle approximation. We also derive the full-sky anisotropy pattern of a collapsing texture knot
Small angle neutron scattering
Directory of Open Access Journals (Sweden)
Cousin Fabrice
2015-01-01
Full Text Available Small Angle Neutron Scattering (SANS is a technique that enables to probe the 3-D structure of materials on a typical size range lying from ∼ 1 nm up to ∼ a few 100 nm, the obtained information being statistically averaged on a sample whose volume is ∼ 1 cm3. This very rich technique enables to make a full structural characterization of a given object of nanometric dimensions (radius of gyration, shape, volume or mass, fractal dimension, specific area… through the determination of the form factor as well as the determination of the way objects are organized within in a continuous media, and therefore to describe interactions between them, through the determination of the structure factor. The specific properties of neutrons (possibility of tuning the scattering intensity by using the isotopic substitution, sensitivity to magnetism, negligible absorption, low energy of the incident neutrons make it particularly interesting in the fields of soft matter, biophysics, magnetic materials and metallurgy. In particular, the contrast variation methods allow to extract some informations that cannot be obtained by any other experimental techniques. This course is divided in two parts. The first one is devoted to the description of the principle of SANS: basics (formalism, coherent scattering/incoherent scattering, notion of elementary scatterer, form factor analysis (I(q→0, Guinier regime, intermediate regime, Porod regime, polydisperse system, structure factor analysis (2nd Virial coefficient, integral equations, characterization of aggregates, and contrast variation methods (how to create contrast in an homogeneous system, matching in ternary systems, extrapolation to zero concentration, Zero Averaged Contrast. It is illustrated by some representative examples. The second one describes the experimental aspects of SANS to guide user in its future experiments: description of SANS spectrometer, resolution of the spectrometer, optimization of
Small angle neutron scattering
International Nuclear Information System (INIS)
Small Angle Neutron Scattering (SANS) is a technique that enables to probe the 3-D structure of materials on a typical size range lying from about 1 nm up to a few 100 nm, the obtained information being statistically averaged on a sample whose volume is ∼ 1 cm3. This very rich technique enables to make a full structural characterization of a given object of nano-metric dimensions (radius of gyration, shape, volume or mass, fractal dimension, specific area... ) through the determination of the form factor as well as the determination of the way objects are organized within in a continuous media, and therefore to describe interactions between them, through the determination of the structure factor. The specific properties of neutrons (possibility of tuning the scattering intensity by using the isotopic substitution, sensitivity to magnetism, negligible absorption, low energy of the incident neutrons) make it particularly interesting in the fields of soft matter, biophysics, magnetic materials and metallurgy. In particular, the contrast variation methods allow to extract some information that cannot be obtained by any other experimental techniques. This course is divided in two parts. The first one is devoted to the description of the principle of SANS: basics (formalism, coherent scattering/incoherent scattering, notion of elementary scatterer), form factor analysis (I(q→0), Guinier regime, intermediate regime, Porod regime, polydisperse system), structure factor analysis (2. Virial coefficient, integral equations, characterization of aggregates), and contrast variation methods (how to create contrast in an homogeneous system, matching in ternary systems, extrapolation to zero concentration, Zero Averaged Contrast). It is illustrated by some representative examples. The second one describes the experimental aspects of SANS to guide user in its future experiments: description of SANS spectrometer, resolution of the spectrometer, optimization of spectrometer
EVALUATION OF NECK SHAFT ANGLE OF FEMUR ON DRY BONES
Directory of Open Access Journals (Sweden)
Radha
2015-04-01
Full Text Available BACKGROUND: Evaluation of the neck shaft angle of femur helps to understand clinical relevance in bio mechanics of the hip joint. It helps for the better treatment of different pathological conditions of hip and femur and also to design prosthesis. Femoral neck shaft angle is important to convey the information regarding the race to which they belong. Hence the present study was under taken to determine the neck shaft angle of femur in humans. OBJECTIVE: 1. To correct the different types of deformity and to have a normal good walking Mechanism. 2. To know the recent methodology and attempt to evaluate the range of normal Angles of femora and their sex differences. METHODS: ANTHROPOMETRIC: 100 Adult dry bones were studied and analyzed . The neck shaft angle of femur was measured by tracing outlines of contours of all femora. RESULTS: The neck shaft angle of the femur have revealed that there is no much difference in between males and females. There was slightly higher 0.2° in females. INTERPRETATION & CONCLUSION: There was no significant gender difference in neck shaft angle. The Knowledge of knowing the neck shaft angle helps to understand the Biomechanics of the hip joint and also for better treatment of pathological condition of hip and femur.
To a question of determining the mining boundary angle in subsidence
Sedlák Vladimír; Novák Josef
2004-01-01
The mining boundary angle, as one of the basic parameters of subsidence, is used a lot of methods at prediction calculation of movements and deformations. The mining boundary angle is used at determining so called the pillar angles at the protected pillar of warehouses on the earth surface. This mining boundary angle together with the mining depth characterises the subsidence measure on the earth surface. The mining boundary angle depends upon geological, hydrogeological relations and deforma...
Directory of Open Access Journals (Sweden)
M. Collaud Coen
2009-07-01
Full Text Available The aerosol light absorption coefficient is an essential parameter involved in atmospheric radiation budget calculations. The Aethalometer (AE has the great advantage of measuring the aerosol light absorption coefficient at several wavelengths, but the derived absorption coefficients are systematically too high when compared to reference methods. Up to now, four different correction algorithms of the AE absorption coefficients have been proposed by several authors. A new correction scheme based on these previously published methods has been developed, which accounts for the optical properties of the aerosol particles embedded in the filter. All the corrections have been tested on six datasets representing different aerosol types and loadings and include multi-wavelength AE and white-light AE. All the corrections have also been evaluated through comparison with a Multi-Angle Absorption Photometer (MAAP for four datasets lasting between 6 months and five years. The modification of the wavelength dependence by the different corrections is analyzed in detail. The performances and the limits of all AE corrections are determined and recommendations are given.
Directory of Open Access Journals (Sweden)
M. Collaud Coen
2010-04-01
Full Text Available The aerosol light absorption coefficient is an essential parameter involved in atmospheric radiation budget calculations. The Aethalometer (AE has the great advantage of measuring the aerosol light absorption coefficient at several wavelengths, but the derived absorption coefficients are systematically too high when compared to reference methods. Up to now, four different correction algorithms of the AE absorption coefficients have been proposed by several authors. A new correction scheme based on these previously published methods has been developed, which accounts for the optical properties of the aerosol particles embedded in the filter. All the corrections have been tested on six datasets representing different aerosol types and loadings and include multi-wavelength AE and white-light AE. All the corrections have also been evaluated through comparison with a Multi-Angle Absorption Photometer (MAAP for four datasets lasting between 6 months and five years. The modification of the wavelength dependence by the different corrections is analyzed in detail. The performances and the limits of all AE corrections are determined and recommendations are given.
Energy Technology Data Exchange (ETDEWEB)
Akeroyd, A.G., E-mail: a.g.akeroyd@soton.ac.uk [School of Physics and Astronomy, University of Southampton Highfield, Southampton SO17 1BJ (United Kingdom); Particle Physics Department, Rutherford Appleton Laboratory, Chilton, Didcot, Oxon OX11 0QX (United Kingdom); Moretti, S., E-mail: S.Moretti@soton.ac.uk [School of Physics and Astronomy, University of Southampton Highfield, Southampton SO17 1BJ (United Kingdom); Particle Physics Department, Rutherford Appleton Laboratory, Chilton, Didcot, Oxon OX11 0QX (United Kingdom); Sugiyama, Hiroaki, E-mail: sugiyama@cc.kyoto-su.ac.jp [Maskawa Institute for Science and Culture, Kyoto Sangyo University, Kyoto 603-8555 (Japan)
2014-01-20
In the Higgs Triplet Model and the neutrinophilic Two-Higgs-Doublet Model the observed neutrinos obtain mass from a vacuum expectation value which is much smaller than the vacuum expectation value of the Higgs boson in the Standard Model. Both models contain a singly charged Higgs boson (H{sup ±}) whose Yukawa coupling is directly related to the neutrino mass (i.e. a “neutrinophilic charged Higgs”). The partial decay widths of H{sup ±} into a charged lepton and a neutrino (H{sup ±}→ℓ{sup ±}ν) depend identically on the neutrino masses and mixings in the two models. We quantify the impact of the recent measurement of sin{sup 2}2θ{sub 13}, which plays a crucial role in determining the magnitude of the branching ratio of H{sup ±}→e{sup ±}ν for the case of a normal neutrino mass ordering if the lightest neutrino mass m{sub 0}<10{sup −3} eV. We also discuss the sizeable dependence of H{sup ±}→μ{sup ±}ν and H{sup ±}→τ{sup ±}ν on sin{sup 2}θ{sub 23}, which would enable information to be obtained on sin{sup 2}θ{sub 23} and the sign of Δm{sub 31}{sup 2} if these decays are measured. Such information would help neutrino oscillation experiments to determine the CP-violating phase δ.
Testing Ionospheric Faraday Rotation Corrections in CASA
Kooi, Jason E.; Moellenbrock, George
2015-04-01
The Earth’s ionosphere introduces direction- and time-dependent effects over a range of physical and temporal scales and so is a major source for unmodeled phase offsets for low frequency radioastronomical observations. Ionospheric effects are often the limiting factor to making sensitive radioastronomical measurements to probe the solar corona or coronal mass ejections at low frequencies (Array (VLA), did not previously have the capability to mitigate ionospheric effects. This algorithm uses GPS-based global ionosphere maps to mitigate the first and second order ionospheric effects (dispersion delay and Faraday rotation, respectively). We investigated several data centers as potential sources for global ionospheric models and chose the International Global Navigation Satellite System Service data product because data from other sources are generally too sparse to use without additional interpolation schemes. This implementation of ionospheric corrections in CASA has been tested on several sets of VLA observations and all of them showed a significant reduction of the dispersion delay. In order to rigorously test CASA’s ability to mitigate ionospheric Faraday rotation, we made VLA full-polarization observations of the standard VLA phase calibrators J0359+5057 and J0423+4150 in August 2014, using L band (1 - 2 GHz), S band (2 - 4 GHz), and C band (4 - 6 GHz) frequencies in the D array configuration. The observations were 4 hours in duration, beginning near local sunrise. In this paper, we give a general description of how these corrections are implemented as well as discussion of the code’s ability to mitigate the ionospheric effects present in these test observations over a range of times and elevation angles. This work was supported at the University of Iowa by grant ATM09-56901.
International Nuclear Information System (INIS)
Full text: In order to obtain meaningful analytical information from an X-Ray Fluorescence spectrometer, it is necessary to correlate measured intensity values with sample concentrations. The ability to do this to a desired level of precision depends on taking care of a number of variables which influence measured intensity values. These variables include: the sample, which needs to be homogeneous, flat and critically thick to the analyte lines used for measurement; the spectrometer, which needs to perform any mechanical movements in a highly reproducible manner; the time taken to measure an analyte line, and the software, which needs to take care of detector dead-time, the contribution of background to the measured signal, the effects of line overlaps and matrix (absorption and enhancement) effects. This presentation will address commonly used correction procedures for matrix effects and their relative success in achieving their objective. Copyright (2002) Australian X-ray Analytical Association Inc
A general Lorentz correction for single-crystal diffractometers
International Nuclear Information System (INIS)
A single-crystal Lorentz correction is derived for the case of a general scan through an out-of-plane reflection on a four-circle diffractometer with relaxed sample-to-detector collimation. When the Lorentz correction is expressed in terms of the incremental steps in the Eulerian setting angles, structure amplitudes observed by different scan trajectories, for example, some angular in real space and others linear in reciprocal space, are put on a common scale, and errors due to known missetting of the angles or rounding off of the angles are avoided. (orig.)
Vorobyev, V; Aihara, H; Asner, D M; Aushev, T; Ayad, R; Badhrees, I; Bahinipati, S; Bakich, A M; Behera, P; Bhardwaj, V; Bhuyan, B; Biswal, J; Bobrov, A; Bondar, A; Bozek, A; Bračko, M; Browder, T E; Červenkov, D; Chekelian, V; Chen, A; Cheon, B G; Chilikin, K; Chistov, R; Cho, K; Chobanova, V; Choi, Y; Cinabro, D; Danilov, M; Dash, N; Di Carlo, S; Doležal, Z; Drásal, Z; Drutskoy, A; Dutta, D; Eidelman, S; Epifanov, D; Farhat, H; Fast, J E; Ferber, T; Fulsom, B G; Gaur, V; Gabyshev, N; Garmash, A; Goldenzweig, P; Greenwald, D; Haba, J; Hayasaka, K; Hayashii, H; Hou, W -S; Inami, K; Inguglia, G; Ishikawa, A; Itoh, R; Iwasaki, Y; Jacobs, W W; Jaegle, I; Joffe, D; Joo, K K; Julius, T; Kang, K H; Kiesling, C; Kim, D Y; Kim, H J; Kim, J B; Kim, K T; Kim, S H; Kinoshita, K; Kodyš, P; Kotchetkov, D; Križan, P; Krokovny, P; Kumar, R; Kumita, T; Kwon, Y -J; Lange, J S; Li, C H; Li, H; Li, L; Li, Y; Libby, J; Liventsev, D; Lubej, M; Masuda, M; Matsuda, T; Matvienko, D; Miyabayashi, K; Miyata, H; Mizuk, R; Mohanty, G B; Moll, A; Moon, H K; Mussa, R; Nakao, M; Nanut, T; Nath, K J; Nayak, M; Negishi, K; Nishida, S; Ogawa, S; Okuno, S; Pakhlov, P; Pakhlova, G; Pal, B; Park, C -S; Park, C W; Park, H; Paul, S; Pedlar, T K; Pestotnik, R; Petrič, M; Piilonen, L E; Rauch, J; Ritter, M; Sakai, Y; Sandilya, S; Sanuki, T; Savinov, V; Schlüter, T; Schneider, O; Schnell, G; Schwanda, C; Schwartz, A J; Seino, Y; Senyo, K; Sevior, M E; Shebalin, V; Shen, C P; Shibata, T -A; Shiu, J -G; Shwartz, B; Simon, F; Sokolov, A; Solovieva, E; Starič, M; Strube, J F; Sumiyoshi, T; Takizawa, M; Tenchini, F; Trabelsi, K; Uchida, M; Uglov, T; Uno, S; Urquijo, P; Usov, Y; Van Hulse, C; Vanhoefer, P; Varner, G; Varvell, K E; Vinokurova, A; Wang, C H; Wang, M -Z; Wang, P; Watanabe, Y; Williams, K M; Won, E; Yamaoka, J; Yamashita, Y; Yashchenko, S; Yelton, J; Zhang, Z P; Zhilich, V; Zhukova, V; Zhulanov, V; Zupanc, A
2016-01-01
We report a measurement of the CP violation parameter $\\varphi_1$ obtained in a time-dependent analysis of $B^0\\to\\overline{D}{}^{(*)0}h^0$ decays followed by $\\overline{D}{}^0\\to K_S^0\\pi^+\\pi^-$ decay. A model-independent measurement is performed using the binned Dalitz plot technique. The measured value is $\\varphi_1 = 11.7^{\\circ}\\pm7.8^{\\circ}({\\rm stat.})\\pm 2.1^{\\circ}({\\rm syst.})$. Treating $\\sin{2\\varphi_1}$ and $\\cos{2\\varphi_1}$ as independent parameters, we obtain $\\sin{2\\varphi_1} = 0.43\\pm 0.27({\\rm stat.})\\pm 0.08({\\rm syst.})$ and $\\cos{2\\varphi_1} = 1.06\\pm 0.33({\\rm stat.})^{+0.21}_{-0.15}({\\rm syst.})$. The results are obtained with a full data sample of $772 \\times 10^6 B\\overline{B}$ pairs collected near the $\\Upsilon(4S)$ resonance with the Belle detector at the KEKB asymmetric-energy $e^+e^-$ collider.
Spinning angle optical calibration apparatus
Beer, Stephen K.; Pratt, II, Harold R.
1991-01-01
An optical calibration apparatus is provided for calibrating and reproducing spinning angles in cross-polarization, nuclear magnetic resonance spectroscopy. An illuminated magnifying apparatus enables optical setting an accurate reproducing of spinning "magic angles" in cross-polarization, nuclear magnetic resonance spectroscopy experiments. A reference mark scribed on an edge of a spinning angle test sample holder is illuminated by a light source and viewed through a magnifying scope. When the "magic angle" of a sample material used as a standard is attained by varying the angular position of the sample holder, the coordinate position of the reference mark relative to a graduation or graduations on a reticle in the magnifying scope is noted. Thereafter, the spinning "magic angle" of a test material having similar nuclear properties to the standard is attained by returning the sample holder back to the originally noted coordinate position.
Fermions tunnelling with quantum gravity correction
liu, Zhen-Yu
2014-01-01
Quantum gravity correction is truly important to study tunnelling process of black hole. Base on the generalized uncertainty principle, we investigate the influence of quantum gravity and the result tell us that the quantum gravity correction accelerates the evaporation of black hole. Using corrected Dirac equation in curved spacetime and Hamilton-Jacobi method, we address the tunnelling of fermions in a 4-dimensional Schwarzschild spacetime. After solving the equation of motion of the spin 1/2 field, we obtain the corrected Hawking temperature. It turns out that the correction depends not only on the mass of black hole but aslo on the mass of emitted fermions. In our calculation, the quantum gravity correction accelerates the increasing of Hawking temperature during the radiation explicitly. This correction leads to the increasing of the evaporation of black hole.
Fermions Tunnelling with Quantum Gravity Correction
International Nuclear Information System (INIS)
Based on the generalized uncertainty principle (GUP), we investigate the correction of quantum gravity to Hawking radiation of black hole by utilizing the tunnelling method. The result tells us that the quantum gravity correction retards the evaporation of black hole. Using the corrected covariant Dirac equation in curved spacetime, we study the tunnelling process of fermions in Schwarzschild spacetime and obtain the corrected Hawking temperature. It turns out that the correction depends not only on the mass of black hole but also on the mass of emitted fermions. In our calculation, the quantum gravity correction slows down the increase of Hawking temperature during the radiation explicitly. This correction leads to the remnants of black hole and avoids the evaporation singularity. (general)
Experimental and computational studies of film cooling with compound angle injection
Energy Technology Data Exchange (ETDEWEB)
Goldstein, R.J.; Eckert, E.R.G.; Patankar, S.V. [Univ. of Minnesota, Minneapolis, MN (United States)] [and others
1995-10-01
The thermal efficiency of gas turbine systems depends largely on the turbine inlet temperature. Recent decades have seen a steady rise in the inlet temperature and a resulting reduction in fuel consumption. At the same time, it has been necessary to employ intensive cooling of the hot components. Among various cooling methods, film cooling has become a standard method for cooling of the turbine airfoils and combustion chamber walls. The University of Minnesota program is a combined experimental and computational study of various film-cooling configurations. Whereas a large number of parameters influence film cooling processes, this research focuses on compound angle injection through a single row and through two rows of holes. Later work will investigate the values of contoured hole designs. An appreciation of the advantages of compound angle injection has risen recently with the demand for more effective cooling and with improved understanding of the flow; this project should continue to further this understanding. Approaches being applied include: (1) a new measurement system that extends the mass/heat transfer analogy to obtain both local film cooling and local mass (heat) transfer results in a single system, (2) direct measurement of three-dimensional turbulent transport in a highly-disturbed flow, (3) the use of compound angle and shaped holes to optimize film cooling performance, and (4) an exploration of anisotropy corrections to turbulence modeling of film cooling jets.
Energy Technology Data Exchange (ETDEWEB)
Gold, S.
2005-07-01
The aim of this work was to examine, by use of XMCD-effect and additional measurements with SQUID-magnetometer, spin moments and hysteresis loops, but also to clarify the intrinsic properties like magnetocrystalline anisotropy, magnetic dipole term, and the nearly quenched orbital moment. The XMCD-measurements were done at the Cr L{sub 2,3}- and the O K-edge. The results for CrO{sub 2} show a strong dependence of the orbital, the sum of spin moment and magnetic dipole term, and the magnetocrystalline anisotropy energy from the angle between rutile a- and c-axis. Even more than the complete orbital moment, two separable and different spectral features show strong alterations of the different orbital moments. In a second part of this work the temperature dependence was investigated. The aim was to clarify the origin of the orbital moment, dipole term, and MAE in dependence of the spin moment and compare the results to different theoretical models. The extracted orbital moments and the magnetic dipole term show the same temperature dependence as the spin moment. In the following a dependence of the squared measured spin moment could be found for the MAE. For the first time the magnetic dipole term could be identified as the reason of the magnetocrystalline anisotropy energy. A strong Cr-O hybridisation was found, which shows in a similar structure and temperature dependence of the orbital moments for Cr L{sub 2,3} and the XMCD effect at O-K edge. (orig.)
Going round the bend: Persistent personal biases in walked angles.
Jetzschke, Simon; Ernst, Marc O; Moscatelli, Alessandro; Boeddeker, Norbert
2016-03-23
For navigation through our environment, we can rely on information from various modalities, such as vision and audition. This information enables us for example to estimate our position relative to the starting position, or to integrate velocity and acceleration signals from the vestibular organ and proprioception to estimate the displacement due to self-motion. To better understand the mechanisms that underlie human navigation we analysed the performance of participants in an angle-walking task in the absence of visual and auditory signals. To this end, we guided them along paths of different lengths and asked them to turn by an angle of ±90°. We found significant biases in turn angles, i.e. systematic deviations from the correct angle and that these were characteristic for individual participants. Varying path length, however, had little effect on turn accuracy and precision. To check whether this idiosyncrasy was persistent over time and present in another type of walking task, we performed a second experiment several weeks later. Here, the same participants were guided to walk angles with varying amplitude. We then asked them to judge whether they had walked an angle larger or smaller than 90° in a two-alternative forced-choice paradigm. The personal bias was highly correlated between the two experiments even though they were conducted weeks apart. The presence of a persistent bias in walked angles in the absence of external directional cues indicates a possible error component for navigation, which is surprisingly time stable and idiosyncratic. PMID:26854843
A study of images of Projective Angles of pulmonary veins
Energy Technology Data Exchange (ETDEWEB)
Wang Jue [Beijing Anzhen Hospital, Beijing (China); Zhaoqi, Zhang [Beijing Anzhen Hospital, Beijing (China)], E-mail: zhaoqi5000@vip.sohu.com; Yu Wei; Miao Cuilian; Yan Zixu; Zhao Yike [Beijing Anzhen Hospital, Beijing (China)
2009-09-15
Aims: In images of magnetic resonance and computed tomography (CT) there are visible angles between pulmonary veins and the coronary, transversal or sagittal section of body. In this study these angles are measured and defined as Projective Angles of pulmonary veins. Several possible influential factors and characters of distribution are studied and analyzed for a better understanding of this imaging anatomic character of pulmonary veins. And it could be the anatomic base of adjusting correctly the angle of the central X-ray of the angiography of pulmonary veins undergoing the catheter ablation of atrial fibrillation (AF). Method: Images of contrast enhanced magnetic resonance angiography (CEMRA) and contrast enhanced computer tomography (CECT) of the left atrium and pulmonary veins of 137 health objects and patients with atrial fibrillation (AF) are processed with the technique of post-processing, and Projective Angles to the coronary and transversal sections are measured and analyzed statistically. Result: Project Angles of pulmonary veins are one of real and steady imaging anatomic characteristics of pulmonary veins. The statistical distribution of variables is relatively concentrated, with a fairly good representation of average value. It is possible to improve the angle of the central X-ray according to the average value in the selective angiography of pulmonary veins undergoing the catheter ablation of AF.
Local Correction of Boolean Functions
Alon, Noga
2011-01-01
A Boolean function f over n variables is said to be q-locally correctable if, given a black-box access to a function g which is "close" to an isomorphism f_sigma of f, we can compute f_sigma(x) for any x in Z_2^n with good probability using q queries to g. We observe that any k-junta, that is, any function which depends only on k of its input variables, is O(2^k)-locally correctable. Moreover, we show that there are examples where this is essentially best possible, and locally correcting some k-juntas requires a number of queries which is exponential in k. These examples, however, are far from being typical, and indeed we prove that for almost every k-junta, O(k log k) queries suffice.
Dancing droplets: Contact angle, drag, and confinement
Benusiglio, Adrien; Cira, Nate; Prakash, Manu
2015-11-01
When deposited on a clean glass slide, a mixture of water and propylene glycol forms a droplet of given contact angle, when both pure liquids spread. (Cira, Benusiglio, Prakash: Nature, 2015). The droplet is stabilized by a gradient of surface tension due to evaporation that induces a Marangoni flow from the border to the apex of the droplets. The apparent contact angle of the droplets depends on both their composition and the external humidity as captured by simple models. These droplets present remarkable properties such as lack of a large pinning force. We discuss the drag on these droplets as a function of various parameters. We show theoretical and experimental results of how various confinement geometries change the vapor gradient and the dynamics of droplet attraction.
Determination of the antetorsional angle at the femur via axial computer tomography
International Nuclear Information System (INIS)
The antetorsional angle was determined in several patient as well as in an isolated femoral bone by means of computer tomography. A comparison with Rippsteins method shows good correlation, taking different definitions of the antetorsional angle into consideration. Due to a mathematical correction method, the CT determination method is independent of the positioning of the patient. (orig.) 891 MG/orig. 892 MB
Pitch perfect: how fruit flies control their body pitch angle.
Whitehead, Samuel C; Beatus, Tsevi; Canale, Luca; Cohen, Itai
2015-11-01
Flapping insect flight is a complex and beautiful phenomenon that relies on fast, active control mechanisms to counter aerodynamic instability. To directly investigate how freely flying Drosophila melanogaster control their body pitch angle against such instability, we perturbed them using impulsive mechanical torques and filmed their corrective maneuvers with high-speed video. Combining experimental observations and numerical simulation, we found that flies correct for pitch deflections of up to 40 deg in 29±8 ms by bilaterally modulating their wings' front-most stroke angle in a manner well described by a linear proportional-integral (PI) controller. Flies initiate this corrective process only 10±2 ms after the perturbation onset, indicating that pitch stabilization involves a fast reflex response. Remarkably, flies can also correct for very large-amplitude pitch perturbations--greater than 150 deg--providing a regime in which to probe the limits of the linear-response framework. Together with previous studies regarding yaw and roll control, our results on pitch show that flies' stabilization of each of these body angles is consistent with PI control. PMID:26385332
Full Text Available ... Jaw Surgery Download Download the ebook for further information Corrective jaw, or orthognathic, surgery is performed by ... your treatment. Correction of Common Dentofacial Deformities The information provided here is not intended as a substitute ...
NWS Corrections to Observations
National Oceanic and Atmospheric Administration, Department of Commerce — Form B-14 is the National Weather Service form entitled 'Notice of Corrections to Weather Records.' The forms are used to make corrections to observations on forms...
Alpha emitters activity measurement using the defined solid angle method
International Nuclear Information System (INIS)
The defined solid angle counting method can reach a very high accuracy, specially for heavy ions as alpha particles emitted by a radioactive source. The activity measurement of such sources with a relative uncertainty of the order of 0.01% is investigated. Such an accuracy is available only under suitable conditions: the radiation emitted by the source must be isotropic and all the particles emitted in the effective solid angle must be detected. The efficiency detection value must be equal to unity and phenomena such as absorption or scattering must be null. It is shown that corrections often become necessary. All parameters which can influence the measurements are studied
Foreign Body Embedded in Anterior Chamber Angle
Directory of Open Access Journals (Sweden)
Shmuel Graffi
2012-01-01
Full Text Available Introduction. We present a case of a metallic foreign body embedded in the anterior chamber angle. After standing in close proximity to a construction worker breaking a tile, a 26-year-old woman using soft contact lens for the correction of mild myopia presented to emergency department for evaluation of a foreign body sensation of her right eye. Methods and Results. Diagnosis was confirmed by gonioscopic examination and a noncontrast CT scan of head and orbits. The foreign body was removed by an external approach without utilizing a magnet. The patient's final outcome was favorable. Discussion. The above is a rare clinical situation, which is impossible to detect on slit-lamp examination without a gonioscopic view. Proper imaging and a specific management are mandatory in order to achieve favorable outcome.
Institute of Scientific and Technical Information of China (English)
Dr. Grace Zhang
2000-01-01
Error correction is an important issue in foreign language acquisition. This paper investigates how students feel about the way in which error correction should take place in a Chinese-as-a foreign-language classroom, based on empirical data of a large scale. The study shows that there is a general consensus that error correction is necessary. In terms of correction strategy, the students preferred a combination of direct and indirect corrections, or a direct only correction. The former choice indicates that students would be happy to take either so long as the correction gets done.Most students didn't mind peer correcting provided it is conducted in a constructive way. More than halfofthe students would feel uncomfortable ifthe same error they make in class is corrected consecutively more than three times. Taking these findings into consideration, we may want to cncourage peer correcting, use a combination of correction strategies (direct only if suitable) and do it in a non-threatening and sensitive way. It is hoped that this study would contribute to the effectiveness of error correction in a Chinese language classroom and it may also have a wider implication on other languages.
Calculations of the Wigner angle
International Nuclear Information System (INIS)
Two new methods to determine Wigner's angle in special relativity are presented. The first one consists in calculating the angle between the compositions u-bar x ν-bar and ν-bar x u-bar of the two non-collinear velocities u-bar and ν-bar. In another method we introduce a generalization in the complex plane of Einstein's addition law of parallel velocities. (author)
A Global Correction to PPMXL Proper Motions
Vickers, John J; Grebel, Eva K
2016-01-01
In this paper we notice that extragalactic sources seem to have non-zero proper motions in the PPMXL proper motion catalog. We collect a large, all-sky sample of extragalactic objects and fit their reported PPMXL proper motions to an ensemble of spherical harmonics in magnitude shells. A magnitude dependent proper motion correction is thus constructed. This correction is applied to a set of fundamental radio sources, quasars, and is compared to similar corrections to assess its utility. We publish, along with this paper, code which may be used to correct proper motions in the PPMXL catalog over the full sky which have 2 Micron All Sky Survey photometry.
Diamond, Jonathan S; Nashed, Joseph Y; Johansson, Roland S; Wolpert, Daniel M; Flanagan, J Randall
2015-07-22
Numerous studies have shown that people are adept at learning novel object dynamics, linking applied force and motion, when performing reaching movements with hand-held objects. Here we investigated whether the control of rapid corrective arm responses, elicited in response to visual perturbations, has access to such newly acquired knowledge of object dynamics. Participants first learned to make reaching movements while grasping an object subjected to complex load forces that depended on the distance and angle of the hand from the start position. During a subsequent test phase, we examined grip and load force coordination during corrective arm movements elicited (within ∼150 ms) in response to viewed sudden lateral shifts (1.5 cm) in target or object position. We hypothesized that, if knowledge of object dynamics is incorporated in the control of the corrective responses, grip force changes would anticipate the unusual load force changes associated with the corrective arm movements so as to support grasp stability. Indeed, we found that the participants generated grip force adjustments tightly coupled, both spatially and temporally, to the load force changes associated with the arm movement corrections. We submit that recently learned novel object dynamics are effectively integrated into sensorimotor control policies that support rapid visually driven arm corrective actions during transport of hand held objects. Significance statement: Previous studies have demonstrated that the motor system can learn, and make use of, internal models of object dynamics to generate feedforward motor commands. However, it is not known whether such internal models are incorporated into rapid, automatic arm movement corrections that compensate for errors that arise during movement. Here we demonstrate, for the first time, that internal models of novel object dynamics are integrated into rapid corrective arm movements made in response to visuomotor perturbations that, importantly, do
Large optical field enhancement for nanotips with large opening angles
Thomas, Sebastian; Lemell, Christoph; Burgdörfer, Joachim; Hommelhoff, Peter
2014-01-01
We theoretically investigate optical near-fields at nanometric tips. We systematically study the dependence of field enhancement on the shape, size, and material of the tip. We confirm a strong dependence of the field enhancement factor on the radius of curvature. In addition, we find a remarkably strong increase of field enhancement with increasing opening angle of the nanotips. For gold and tungsten nanotips in the experimentally relevant parameter range (radius of curvature $\\geq 5\\,$nm at 800 nm laser wavelength), we obtain field enhancement factors of up to ${\\sim}35$ (Au) and ${\\sim}12$ (W) for wide opening angles. We confirm this strong dependence on the opening angle for many other materials studying the dependence of the field enhancement at nanotips on the dielectric response function. For dielectrics, the increase in field enhancement is traced back to the electrostatic force of the induced surface charge at the tip shank. For metals, the plasmonic response strongly increases the field enhancement ...
On gravitational and thermal corrections to vacuum decay
Salvio, Alberto; Tetradis, Nikolaos; Urbano, Alfredo
2016-01-01
We reconsider gravitational corrections to vacuum decay, confirming and simplifying earlier results and extending them allowing for a non-minimal coupling of the Higgs to gravity, finding that leading-order gravitational corrections suppress the vacuum decay rate. Furthermore, we find minor corrections to thermal vacuum decay in the SM adding one-loop corrections to the Higgs kinetic term, two-loop corrections to the Higgs potential and allowing for time-dependent bounces.
Scattering Angle Dependence of Weak Mixing Angle at Noncommutative Mass Poles
Shio, C.
2001-01-01
There have been comments on the starting paper, hep-th/0106074, which point out unclear motivation and definitions on noncommutative momentum introduced. This paper is withdrawn by the author for more clear presentation.
Apparent dynamic contact angle of an advancing gas--liquid meniscus
International Nuclear Information System (INIS)
The steady motion of an advancing meniscus in a gas-filled capillary tube involves a delicate balance of capillary, viscous, and intermolecular forces. The limit of small capillary numbers Ca (dimensionless speeds) is analyzed here with a matched asymptotic analysis that links the outer capillary region to the precursor film in front of the meniscus through a lubricating film. The meniscus shape in the outer region is constructed and the apparent dynamic contact angle Θ that the meniscus forms with the solid surface is derived as a function of the capillary number, the capillary radius, and the Hamaker's constant for intermolecular forces, under conditions of weak gas--solid interaction, which lead to fast spreading of the precursor film and weak intermolecular forces relative to viscous forces within the lubricating film. The dependence on intermolecular forces is very weak and the contact angle expression has a tight upper bound tan Θ=7.48 Ca1/3 for thick films, which is independent of the Hamaker constant. This upper bound is in very good agreement with existing experimental data for wetting fluids in any capillary and for partially wetting fluids in a prewetted capillary. Significant correction to the Ca1/3 dependence occurs only at very low Ca, where the intermolecular forces become more important and tan Θ diverges slightly from the above asymptotic behavior toward lower values
Correction of broadband snow albedo measurements affected by unknown slope and sensor tilts
Weiser, Ursula; Olefs, Marc; Schöner, Wolfgang; Weyss, Gernot; Hynek, Bernhard
2016-04-01
Geometric effects induced by the underlying terrain slope or by tilt errors of the radiation sensors lead to an erroneous measurement of snow or ice albedo. Consequently, artificial diurnal albedo variations in the order of 1-20 % are observed. The present paper proposes a general method to correct tilt errors of albedo measurements in cases where tilts of both the sensors and the slopes are not accurately measured or known. We demonstrate that atmospheric parameters for this correction model can either be taken from a nearby well-maintained and horizontally levelled measurement of global radiation or alternatively from a solar radiation model. In a next step the model is fitted to the measured data to determine tilts and directions of sensors and the underlying terrain slope. This then allows us to correct the measured albedo, the radiative balance and the energy balance. Depending on the direction of the slope and the sensors a comparison between measured and corrected albedo values reveals obvious over- or underestimations of albedo. It is also demonstrated that differences between measured and corrected albedo are generally highest for large solar zenith angles.
Diphotons, New Vacuum Angles, and Strong CP
Draper, Patrick
2016-01-01
The Standard Model contains a well-understood, natural, spin-0 diphoton resonance: the $\\pi^0$. Numerous studies have pointed out that the hint of a new diphoton resonance at 750 GeV could be a pion analog, identified with the pseudo-Nambu-Goldstone boson of a chiral symmetry spontaneously broken by new strong dynamics at the TeV scale. These "hypercolor" models are generically expected to violate parity through a topological angle $\\tilde\\theta$. We discuss the physics of $\\tilde\\theta$ and its impact on the phenomenology of the new sector. We also describe some of the theoretical implications of a nonzero $\\tilde\\theta$. In particular, $\\tilde\\theta$ can generate an ${\\cal O}(1)$ threshold correction to the QCD vacuum angle $\\theta$ near the TeV scale, sharply constraining ultraviolet solutions to the strong CP problem. Alternatively, finding that $\\tilde\\theta$ is small may be interpreted as evidence in favor of UV solutions to strong CP, particularly those based on spontaneously broken P or CP symmetries.
Active limited-angle tomographic phase microscope
Kuś, Arkadiusz; Krauze, Wojciech; Kujawińska, Małgorzata
2015-11-01
We demonstrate an active, holographic tomography system, working with limited angle of projections, realized by optical-only, diffraction-based beam steering. The system created for this purpose is a Mach-Zehnder interferometer modified to serve as a digital holographic microscope with a high numerical aperture illumination module and a spatial light modulator (SLM). Such a solution is fast and robust. Apart from providing an elegant solution to viewing angle shifting, it also adds new capabilities of the holographic microscope system. SLM, being an active optical element, allows wavefront correction in order to improve measurement accuracy. Integrated phase data captured with different illumination scenarios within a highly limited angular range are processed by a new tomographic reconstruction algorithm based on the compressed sensing technique: total variation minimization, which is applied here to reconstruct nonpiecewise constant samples. Finally, the accuracy of full measurement and the proposed processing path is tested for a calibrated three-dimensional micro-object as well as a biological object-C2C12 myoblast cell.
Diphotons, new vacuum angles, and strong CP
Draper, Patrick; McKeen, David
2016-04-01
The Standard Model contains a well-understood, natural, spin-0 diphoton resonance: the π 0. Numerous studies have pointed out that the hint of a new diphoton resonance at 750 GeV could be a pion analog, identified with the pseudo-Nambu-Goldstone boson of a chiral symmetry spontaneously broken by new strong dynamics at the TeV scale. These "hypercolor" models are generically expected to violate parity through a topological angle tilde{θ} . We discuss the physics of tilde{θ} and its impact on the phenomenology of the new sector. We also describe some of the theoretical implications of a nonzero tilde{θ} . In particular, tilde{θ} can generate an O(1) threshold correction to the QCD vacuum angle θ near the TeV scale, sharply constraining ultraviolet solutions to the strong CP problem. Alternatively, finding that tilde{θ} is small may be interpreted as evidence in favor of UV solutions to strong CP, particularly those based on spontaneously broken P or CP symmetries.
Radiative Corrections to Democratic Lepton Mixing
Mei, J; Mei, Jianwei; Xing, Zhi-Zhong
2005-01-01
A new ansatz of democratic lepton mixing is proposed at the GUT scale and the radiative corrections to its phenomenological consequences are calculated at the electroweak scale. We demonstrate that it is possible to obtain the experimentally favored results for both neutrino masses and lepton flavor mixing angles from this ansatz, provided the neutrino Yukawa coupling matrix takes a specific nontrivial pattern. The seesaw threshold effects play a significant role in the running of relevant physical quantities.
Path Integral Solution for an Angle-Dependent Anharmonic Oscillator
Institute of Scientific and Technical Information of China (English)
S.Haouat
2012-01-01
We have given a straightforward method to solve the problem of noncentral anharmonic oscillator in three dimensions. The relative propagator is presented by means of path integrals in spherical coordinates. By making an adequate change of time we are able to separate the angular motion from the radial one. The relative propagator is then exactly calculated. The energy spectrum and the corresponding wave functions are obtained.
Control of Angular Intervals for Angle-Multiplexed Holographic Memory
Kinoshita, Nobuhiro; Muroi, Tetsuhiko; Ishii, Norihiko; Kamijo, Koji; Shimidzu, Naoki
2009-03-01
In angle-multiplexed holographic memory, the full width at half maximum of the Bragg selectivity curves is dependent on the angle formed between the medium and incident laser beams. This indicates the possibility of high density and high multiplexing number by varying the angular intervals between adjacent holograms. We propose an angular interval scheduling for closely stacking holograms into medium even when the angle range is limited. We obtained bit error rates of the order of 10-4 under the following conditions: medium thickness of 1 mm, laser beam wavelength of 532 nm, and angular multiplexing number of 300.
Measurement of the angle of superficial tension by images
Yanez M., Javier; Alonso R., Sergio
2006-02-01
When a liquid is deposited on a surface, this one form a certain angle with respect to the surface, where depending on its value, it will conclude that so hard it is his adhesion with the surface. By means of the analysis of images we looked for to measure this angle of superficial tension. In order to make this measurement, we propose a technique by means of projective transformations and one method of regression to estimation parameters to conic fitting.
Neoclassical Pitch-Angle Scattering of Runaway Electrons
Liu, Jian; Qin, Hong
2015-01-01
It is discovered that the tokamak field geometry generates a pitch-angle scattering effect for runaway electrons. This neoclassical pitch-angle scattering is much stronger than the collisional scattering and invalidates the gyro-center model for runaway electrons. As a result, the energy limit of runaway electrons is found to be larger than the prediction of the gyro-center model and to depend heavily on the background magnetic field.
Correct Linearization of Einstein's Equations
Directory of Open Access Journals (Sweden)
Rabounski D.
2006-06-01
Full Text Available Regularly Einstein's equations can be reduced to a wave form (linearly dependent from the second derivatives of the space metric in the absence of gravitation, the space rotation and Christoffel's symbols. As shown here, the origin of the problem is that one uses the general covariant theory of measurement. Here the wave form of Einstein's equations is obtained in the terms of Zelmanov's chronometric invariants (physically observable projections on the observer's time line and spatial section. The obtained equations depend on solely the second derivatives even if gravitation, the space rotation and Christoffel's symbols. The correct linearization proves: the Einstein equations are completely compatible with weak waves of the metric.
Low angle neutron data acquisition system for molecular biology
International Nuclear Information System (INIS)
The low angle spectrometer system utilizing a 2-dimensional position sensitive counter was designed to accommodate a variety of experiments in molecular biology requiring good low angle resolution. Biological structures requiring low angle analysis techniques fall into two groups: non-ordered systems (proteins or protein complexes in solution) and ordered systems with large spacings like muscle, collagen, and membranes. For structural investigations into such systems, data are ideally needed to a low scattering angle of 0.20 at 4.5 A or a minimum Q of 0.005 A-1 (Q = theta . 2π/lambda). Depending on the type of structure, data often extend to the high angle region, say 300. Apart from the low angle requirements, the spectrometer has to have good resolution to resolve diffraction peaks from samples with crystal spacings up to 1000 A or even larger. While it is desirable to build a spectrometer to such scattering conditions, given reactor conditions might not permit this and compromises have to be made between flux, resolution and lowest angle. The low angle spectrometer described here was designed to be used at the HFBR neutron beam pipe working at approximately 4.2 A or at the H4 satellite station working at 2.4 A
Wake angle for surface gravity waves on a finite depth fluid
Pethiyagoda, Ravindra; McCue, Scott W.; Moroney, Timothy J.
2015-01-01
Linear water wave theory suggests that wave patterns caused by a steadily moving disturbance are contained within a wedge whose half-angle depends on the depth-based Froude number $F_H$. For the problem of flow past an axisymmetric pressure distribution in a finite-depth channel, we report on the apparent angle of the wake, which is the angle of maximum peaks. For moderately deep channels, the dependence of the apparent wake angle on the Froude number is very different to the wedge angle, and...
Off-level corrections for gravity meters
Niebauer, T. M.; Blitz, Thomas; Constantino, Andy
2016-04-01
Gravity meters must be aligned with the local gravity at any location on the surface of the earth in order to measure the full amplitude of the gravity vector. The gravitational force on the sensitive component of the gravity meter decreases by the cosine of the angle between the measurement axis and the local gravity vector. Most gravity meters incorporate two horizontal orthogonal levels to orient the gravity meter for a maximum gravity reading. In order to calculate a gravity correction it is often necessary to estimate the overall angular deviation between the gravity meter and the local gravity vector using two measured horizontal tilt meters. Typically this is done assuming that the two horizontal angles are independent and that the product of the cosines of the horizontal tilts is equivalent to the cosine of the overall deviation. These approximations, however, break down at large angles. This paper derives analytic formulae to transform angles measured by two orthogonal tilt meters into the vertical deviation of the third orthogonal axis. The equations can be used to calibrate the tilt sensors attached to the gravity meter or provide a correction for a gravity meter used in an off-of-level condition.
Modulation of cross polarization in motionally averaged solids by Variable Angle Spinning NMR
Espinosa, Catalina A.; Thureau, Pierre; Shapiro, Rebecca A.; Litvak, Ilya M.; Martin, Rachel W.
2011-01-01
In systems where the dipolar couplings are partially averaged by molecular motion, cross-polarization is modulated by sample spinning. The cross-polariation efficiency in Variable Angle Spinning (VAS) and Switched Angle Spinning (SAS) experiments on mobile samples is therefore strongly dependent on the spinning angle. We describe simulations and experimental measurements of these effects over a range of spinning angles from 0° to 90°.
Large-angle Bhabha scattering at LEP 1
Beenakker, Wim; Passarino, Giampiero
1998-04-01
A critical assessment is given of the theoretical uncertainty in the predicted cross-sections for large-angle Bhabha scattering at LEP 1, with or without t-channel subtraction. To this end a detailed comparison is presented of the results obtained with the programs ALIBABA and TOPAZ0. Differences in the implementation of the radiative corrections and the effect of missing higher-order terms are critically discussed. © 1998
Large-Angle Bhabha Scattering at LEP 1
Wim BeenakkerLeiden Univ.; Giampiero Passarino(Dipartimento di Fisica Teorica, Università di Torino, Italy)
1997-01-01
A critical assessment is given of the theoretical uncertainty in the predicted cross-sections for large-angle Bhabha scattering at LEP 1, with or without t-channel subtraction. To this end a detailed comparison is presented of the results obtained with the programs ALIBABA and TOPAZ0. Differences in the implementation of the radiative corrections and the effect of missing higher-order terms are critically discussed.
Large-Angle Bhabha Scattering at LEP 1
Beenakker, W; Beenakker, Wim; Passarino, Giampiero
1998-01-01
A critical assessment is given of the theoretical uncertainty in the predicted cross-sections for large-angle Bhabha scattering at LEP 1, with or without t-channel subtraction. To this end a detailed comparison is presented of the results obtained with the programs ALIBABA and TOPAZ0. Differences in the implementation of the radiative corrections and the effect of missing higher-order terms are critically discussed.
Frequency scaling for angle gathers
Zuberi, M. A H
2014-01-01
Angle gathers provide an extra dimension to analyze the velocity after migration. Space-shift and time shift-imaging conditions are two methods used to obtain angle gathers, but both are reasonably expensive. By scaling the time-lag axis of the time-shifted images, the computational cost of the time shift imaging condition can be considerably reduced. In imaging and more so Full waveform inversion, frequencydomain Helmholtz solvers are used more often to solve for the wavefields than conventional time domain extrapolators. In such cases, we do not need to extend the image, instead we scale the frequency axis of the frequency domain image to obtain the angle gathers more efficiently. Application on synthetic data demonstrate such features.
Orientation angle and the adhesion of single gecko setae.
Hill, Ginel C; Soto, Daniel R; Peattie, Anne M; Full, Robert J; Kenny, T W
2011-07-01
We investigated the effects of orientation angle on the adhesion of single gecko setae using dual-axis microelectromechanical systems force sensors to simultaneously detect normal and shear force components. Adhesion was highly sensitive to the pitch angle between the substrate and the seta's stalk. Maximum lateral adhesive force was observed with the stalk parallel to the substrate, and adhesion decreased smoothly with increasing pitch. The roll orientation angle only needed to be roughly correct with the spatular tuft of the seta oriented grossly towards the substrate for high adhesion. Also, detailed measurements were made to control for the effect of normal preload forces. Higher normal preload forces caused modest enhancement of the observed lateral adhesive force, provided that adequate contact was made between the seta and the substrate. These results should be useful in the design and manufacture of gecko-inspired synthetic adhesives with anisotropic properties, an area of substantial recent research efforts. PMID:21288955
Experimental investigation of synthetic aperture flow angle estimation
DEFF Research Database (Denmark)
Oddershede, Niels; Jensen, Jørgen Arendt
2005-01-01
Currently synthetic aperture flow methods can find the correct velocity magnitude, when the flow direction is known. To make a fully automatic system, the direction should also be estimated. Such an approach has been suggested by Jensen (2004) based on a search of the highest cross-correlation as a...... function of velocity and angle. This paper presents an experimental investigation of this velocity angle estimation method based on a set of synthetic aperture flow data measured using our RASMUS experimental ultrasound system. The measurements are performed for flow angles of 60, 75, and 90 deg. with...... respect to the axial direction, and for constant velocities with a peak of 0.1 m/s and 0.2 m/s. The implemented synthetic aperture imaging method uses virtual point sources in front of the transducer, and recursive imaging is used to increase the data rate. A 128 element linear array transducer is used...
Systematic variations in divergence angle
Okabe, Takuya
2012-01-01
Practical methods for quantitative analysis of radial and angular coordinates of leafy organs of vascular plants are presented and applied to published phyllotactic patterns of various real systems from young leaves on a shoot tip to florets on a flower head. The constancy of divergence angle is borne out with accuracy of less than a degree. It is shown that apparent fluctuations in divergence angle are in large part systematic variations caused by the invalid assumption of a fixed center and/or by secondary deformations, while random fluctuations are of minor importance.
Defocus and twofold astigmatism correction in HAADF-STEM
Energy Technology Data Exchange (ETDEWEB)
Rudnaya, M.E., E-mail: m.rudnaya@tue.nl [CASA, Department of Mathematics and Computer Science, Eindhoven University of Technology, PO Box 513, 5600 MB Eindhoven (Netherlands); Van den Broek, W. [EMAT, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp (Belgium); Doornbos, R.M.P. [Embedded Systems Institute, PO Box 513, 5600 MB Eindhoven (Netherlands); Mattheij, R.M.M.; Maubach, J.M.L. [CASA, Department of Mathematics and Computer Science, Eindhoven University of Technology, PO Box 513, 5600 MB Eindhoven (Netherlands)
2011-07-15
A new simultaneous autofocus and twofold astigmatism correction method is proposed for High Angle Annular Dark Field Scanning Transmission Electron Microscopy (HAADF-STEM). The method makes use of a modification of image variance, which has already been used before as an image quality measure for different types of microscopy, but its use is often justified on heuristic grounds. In this paper we show numerically that the variance reaches its maximum at Scherzer defocus and zero astigmatism. In order to find this maximum a simultaneous optimization of three parameters (focus, x- and y-stigmators) is necessary. This is implemented and tested on a FEI Tecnai F20. It successfully finds the optimal defocus and astigmatism with time and accuracy, compared to a human operator. -- Research highlights: {yields} A new simultaneous defocus and astigmatism correction method is proposed. {yields} The method does not depend on the image Fourier transform. {yields} The method does not require amorphous area of the sample. {yields} The method is tested numerically as well, as for the real-world application.
Defocus and twofold astigmatism correction in HAADF-STEM
International Nuclear Information System (INIS)
A new simultaneous autofocus and twofold astigmatism correction method is proposed for High Angle Annular Dark Field Scanning Transmission Electron Microscopy (HAADF-STEM). The method makes use of a modification of image variance, which has already been used before as an image quality measure for different types of microscopy, but its use is often justified on heuristic grounds. In this paper we show numerically that the variance reaches its maximum at Scherzer defocus and zero astigmatism. In order to find this maximum a simultaneous optimization of three parameters (focus, x- and y-stigmators) is necessary. This is implemented and tested on a FEI Tecnai F20. It successfully finds the optimal defocus and astigmatism with time and accuracy, compared to a human operator. -- Research highlights: → A new simultaneous defocus and astigmatism correction method is proposed. → The method does not depend on the image Fourier transform. → The method does not require amorphous area of the sample. → The method is tested numerically as well, as for the real-world application.
Diophantine Correct Open Induction
Raffer, Sidney
2010-01-01
We give an induction-free axiom system for diophantine correct open induction. We relate the problem of whether a finitely generated ring of Puiseux polynomials is diophantine correct to a problem about the value-distribution of a tuple of semialgebraic functions with integer arguments. We use this result, and a theorem of Bergelson and Leibman on generalized polynomials, to identify a class of diophantine correct subrings of the field of descending Puiseux series with real coefficients.
INS as a probe of inter-monomer angles in polymers
Eijck, L V; Grozema, F C; Schepper, I M D; Kearley, G J
2002-01-01
The angle between monomers in conjugated polymers plays an important role in their conductivity. The vibrational spectrum is sensitive to this angle and can be used to probe the distribution of angles in poorly crystalline systems. We show that the INS spectrum is correctly calculated for bithiophene and shows the molecule to be planar in the solid - in agreement with crystallographic measurements. Poor agreement between observed and calculated spectra in the 700-cm sup - sup 1 region may be due to dynamic coupling, but this does not detract from the angle-sensitivity of the spectra. (orig.)
Angle measurement error and compensation for decentration rotation of circular gratings
Institute of Scientific and Technical Information of China (English)
CHEN Xi-jun; WANG Zhen-huan; ZENG Qing-shuang
2010-01-01
As the geometric center of circular grating does not coincide with the rotation center,the angle measurement error of circular grating is analyzed.Based on the moire fringe equations in decentration condition,the mathematical model of angle measurement error is derived.It is concluded that the deeentration between the centre of circular grating and the center of revolving shaft leads to the first-harmonic error of angle measurement.The correctness of the result is proved by experimental data.The method of error compensation is presented,and the angle measurement accuracy of the circular grating is effectively improved by the error compensation.
DEFF Research Database (Denmark)
Dalskov, Erik K.; Jensen, Hans Jørgen Aa; Oddershede, Jens
1997-01-01
an underestimation of the frequency dependence if scaling or addition is applied. There does not seem to be a simple way to infer anything about the validity of scaling or addition for β∥ from either the lower lying excitations and their intensities or from the frequency dependence of the dipole...
Corrections to measurements of pion capture ratios
International Nuclear Information System (INIS)
The authors conclude that the electromagnetic corrections to the C/O pion capture ratios deduced from the summed intensities of pionic Balmer series are small, and much less than their experimental errors. The magnitude of the correction due to nuclear absorption depends on the initial angular momentum distribution which in turn depends on molecular structure. The dependence of the capture ratios on molecular structure has raised serious questions about the effect on dose calculations for pion radiotherapy and on the definition of tissue equivalence for pions. (U.K.)
Discovering the Inscribed Angle Theorem
Roscoe, Matt B.
2012-01-01
Learning to play tennis is difficult. It takes practice, but it also helps to have a coach--someone who gives tips and pointers but allows the freedom to play the game on one's own. Learning to act like a mathematician is a similar process. Students report that the process of proving the inscribed angle theorem is challenging and, at times,…
Contactless angle detection using permalloy
Eijkel, Kees J.; Rijk, Rolf
1988-01-01
An overview is given of measurements on angle detectors. The detectors consist of a pair of planar-Hall elements opposite to a rotatable magnet. The measurements are performed on a number of planar-Hall elements of different shape and size, and show good agreement with a previously described theoret
Limbus Impact on Off-angle Iris Degradation
Energy Technology Data Exchange (ETDEWEB)
Karakaya, Mahmut [ORNL; Barstow, Del R [ORNL; Santos-Villalobos, Hector J [ORNL; Thompson, Joseph W [ORNL; Bolme, David S [ORNL; Boehnen, Chris Bensing [ORNL
2013-01-01
The accuracy of iris recognition depends on the quality of data capture and is negatively affected by several factors such as angle, occlusion, and dilation. Off-angle iris recognition is a new research focus in biometrics that tries to address several issues including corneal refraction, complex 3D iris texture, and blur. In this paper, we present an additional significant challenge that degrades the performance of the off-angle iris recognition systems, called the limbus effect . The limbus is the region at the border of the cornea where the cornea joins the sclera. The limbus is a semitransparent tissue that occludes a side portion of the iris plane. The amount of occluded iris texture on the side nearest the camera increases as the image acquisition angle increases. Without considering the role of the limbus effect, it is difficult to design an accurate off-angle iris recognition system. To the best of our knowledge, this is the first work that investigates the limbus effect in detail from a biometrics perspective. Based on results from real images and simulated experiments with real iris texture, the limbus effect increases the hamming distance score between frontal and off-angle iris images ranging from 0.05 to 0.2 depending upon the limbus height.
Spelling Correction in Context
Pinot, Guillaume; Enguehard, Chantal
2005-01-01
International audience Spelling checkers, frequently used nowadays, do not allow to correct real-word errors. Thus, the erroneous replacement of dessert by desert is not detected. We propose in this article an algorithm based on the examination of the context of words to correct this kind of spelling errors. This algorithm uses a training on a raw corpus.
Derivative corrections from noncommutativity
International Nuclear Information System (INIS)
We show that an infinite subset of the higher-derivative α' corrections to the DBI and Chern-Simons actions of ordinary commutative open-string theory can be determined using noncommutativity. Our predictions are compared to some lowest order α' corrections that have been computed explicitly by Wyllard (hep-th/0008125), and shown to agree. (author)
RESEARCH OF BASIFACIAL CONTOURING SCULPTURE BY MANDIBULAR ANGLE OSTECTOMY
Institute of Scientific and Technical Information of China (English)
FANG Jian-lin; DAI Chuan-chang; ZHU Guo-xian; ZHANG Ying; JIN Yu-qing; WANG Wei; QI Chuan-liang
2006-01-01
Objective Mandibular angle ostectomy is usually applied to the facial contouring sculpture.We evaluated the various techniques in order to enhance the precision and avoid unnecessary damage. Methods Before operation the area and quantity resected bone were designed according to facial measurement, mandible pantomography and orthophoria and lateral localized radiograph of skull. The Incises of mandibular angle ostectomy included intraoral, retroauricular or intraoral associated with retroauricular. Howerer, the sagittal resection of mandible outer table was necessary in all intraoral incise. Results Single mandibular angle ostectomy was not satisfactory for the patients having mandible hypertrophy with over-width basifacial contouring. Mandibular angle ostectomy combined with the sagittal resection of outer table of mandibular angle were required. Good symmetry and ap pearance were gained in 206 cases. One case had facial paralysis. Two patients occured mandibular fracture during the operation. Three cases complicated angled deformity at mandible body. Conclusion Reduction mandibuloplasty should be selected depends on varied types of mandibular angle hypertrophy before operation.
van Roekeghem, Ambroise; Richard, Pierre; Shi, Xun; Wu, Shangfei; Zeng, Lingkun; Saparov, Bayrammurad; Ohtsubo, Yoshiyuki; Qian, Tian; Sefat, Athena S.; Biermann, Silke; Ding, Hong
2016-06-01
We present a study of the tetragonal to collapsed-tetragonal transition of CaFe2As2 using angle-resolved photoemission spectroscopy and dynamical mean field theory-based electronic structure calculations. We observe that the collapsed-tetragonal phase exhibits reduced correlations and a higher coherence temperature due to the stronger Fe-As hybridization. Furthermore, a comparison of measured photoemission spectra and theoretical spectral functions shows that momentum-dependent corrections to the density functional band structure are essential for the description of low-energy quasiparticle dispersions. We introduce those using the recently proposed combined "screened exchange + dynamical mean field theory" scheme.
International Nuclear Information System (INIS)
QCD corrections to order αs in the soft-gluon approximation to angular distributions of decay charged leptons in the process e+ e- → t t-bar, followed by semileptonic decay of t or t-bar, are obtained in the e+e- centre-of-mass frame. As compared to distributions in the top rest frame, these have the advantage that they would allow direct comparison with experiment without the need to reconstruct the top rest frame. The results also do not depend on the choice of a spin quantization axis for t or t-bar. Analytic expression for the triple distribution in the polar angle of t and polar and azimuthal angles of the lepton is obtained. Analytic expression is also derived for the distribution in the charged-lepton polar angle. Numerical values are discussed for √s = 400, 800 and 1500 GeV. (author)
Rindani, S D
2002-01-01
QCD corrections to order alpha_s in the soft-gluon approximation to angular distributions of decay charged leptons in the process e+e- -> t tbar followed by semileptonic decay of t or tbar, are obtained in the e+e- centre-of-mass frame. As compared to distributions in the top rest frame, these have the advantage that they would allow direct comparison with experiment without the need to reconstruct the top rest frame. The results also do not depend on the choice of a spin quantization axis for t or tbar. Analytic expression for the triple distribution in the polar angle of t and polar and azimuthal angles of the lepton is obtained. Analytic expression is also derived for the distribution in the charged-lepton polar angle. Numerical values are discussed for total c.m. energies of 400 GeV, 800 GeV and 1500 GeV.
Indian Academy of Sciences (India)
Saurabh D Rindani
2002-04-01
QCD corrections to order in the soft-gluon approximation to angular distributions of decay charged leptons in the process $e^{+}e^{-}→ t\\overline{t}$, followed by semileptonic decay of or $\\overline{t}$, are obtained in the $e^{+} e^{-}$ centre-of-mass frame. As compared to distributions in the top rest frame, these have the advantage that they would allow direct comparison with experiment without the need to reconstruct the top rest frame. The results also do not depend on the choice of a spin quantization axis for or $\\overline{t}$. Analytic expression for the triple distribution in the polar angle of and polar and azimuthal angles of the lepton is obtained. Analytic expression is also derived for the distribution in the charged-lepton polar angle. Numerical values are discussed for $\\sqrt{s} = 400$, 800 and 1500 GeV.
Scattering-angle based filtering of the waveform inversion gradients
Alkhalifah, Tariq Ali
2014-11-22
Full waveform inversion (FWI) requires a hierarchical approach to maneuver the complex non-linearity associated with the problem of velocity update. In anisotropic media, the non-linearity becomes far more complex with the potential trade-off between the multiparameter description of the model. A gradient filter helps us in accessing the parts of the gradient that are suitable to combat the potential non-linearity and parameter trade-off. The filter is based on representing the gradient in the time-lag normalized domain, in which the low scattering angle of the gradient update is initially muted out in the FWI implementation, in what we may refer to as a scattering angle continuation process. The result is a low wavelength update dominated by the transmission part of the update gradient. In this case, even 10 Hz data can produce vertically near-zero wavenumber updates suitable for a background correction of the model. Relaxing the filtering at a later stage in the FWI implementation allows for smaller scattering angles to contribute higher-resolution information to the model. The benefits of the extended domain based filtering of the gradient is not only it\\'s ability in providing low wavenumber gradients guided by the scattering angle, but also in its potential to provide gradients free of unphysical energy that may correspond to unrealistic scattering angles.
Wake angle for surface gravity waves on a finite depth fluid
Pethiyagoda, Ravindra; Moroney, Timothy J
2015-01-01
Linear water wave theory suggests that wave patterns caused by a steadily moving disturbance are contained within a wedge whose half-angle depends on the depth-based Froude number $F_H$. For the problem of flow past an axisymmetric pressure distribution in a finite-depth channel, we report on the apparent angle of the wake, which is the angle of maximum peaks. For moderately deep channels, the dependence of the apparent wake angle on the Froude number is very different to the wedge angle, and varies smoothly as $F_H$ passes through the critical value $F_H=1$. For shallow water, the two angles tend to follow each other more closely, which leads to very large apparent wake angles for certain regimes.
Optimum projection angle for attaining maximum distance in a soccer punt kick.
Linthorne, Nicholas P; Patel, Dipesh S
2011-01-01
To produce the greatest horizontal distance in a punt kick the ball must be projected at an appropriate angle. Here, we investigated the optimum projection angle that maximises the distance attained in a punt kick by a soccer goalkeeper. Two male players performed many maximum-effort kicks using projection angles of between 10° and 90°. The kicks were recorded by a video camera at 100 Hz and a 2 D biomechanical analysis was conducted to obtain measures of the projection velocity, projection angle, projection height, ball spin rate, and foot velocity at impact. The player's optimum projection angle was calculated by substituting mathematical equations for the relationships between the projection variables into the equations for the aerodynamic flight of a soccer ball. The calculated optimum projection angles were in agreement with the player's preferred projection angles (40° and 44°). In projectile sports even a small dependence of projection velocity on projection angle is sufficient to produce a substantial shift in the optimum projection angle away from 45°. In the punt kicks studied here, the optimum projection angle was close to 45° because the projection velocity of the ball remained almost constant across all projection angles. This result is in contrast to throwing and jumping for maximum distance, where the projection velocity the athlete is able to achieve decreases substantially with increasing projection angle and so the optimum projection angle is well below 45°. Key pointsThe optimum projection angle that maximizes the distance of a punt kick by a soccer goalkeeper is about 45°.The optimum projection angle is close to 45° because the projection velocity of the ball is almost the same at all projection angles.This result is in contrast to throwing and jumping for maximum distance, where the optimum projection angle is well below 45° because the projection velocity the athlete is able to achieve decreases substantially with increasing
Supracondylar Osteotomy in Valgus Knee: Angle Blade Plate Versus Locking Compression Plate
Kazemi, Seyyed Morteza; Minaei, Reza; Safdari, Farshad; Keipourfard, Ali; Forghani, Rozhin; Mirzapourshafiei, Alemeh
2016-01-01
Background: There are few studies comparing the biomechanical properties of angled blade plate and locking compression plates in supracondylar osteotomy. In the current randomized study, we prospectively compared the clinical and radiological outcomes of supracondylar osteotomy using these two plates. Methods: Forty patients with valgus knee malalignment were randomly assigned to two equal numbered groups: angled blade plate and locking compression plates. All of the patients underwent medial closing wedge supracondylar osteotomy and were followed for one year. Before and after the operation the valgus angle and mechanical lateral distal femoral angle were compared between groups. Also, the rate of complications were compared. Results: After the operation, the mean valgus angle and mechanical lateral distal femoral angle improved significantly in the two groups (P<0.001). Although, the preoperative amount of the valgus angle and mechanical lateral distal femoral angle were the same, at the last visit the valgus angle (5.4±2.1 versus 3.1±1.8; P=0.032) and mechanical lateral distal femoral angle (87.6±2 versus 89.7±3.2; P=0.041) were significantly lower and higher in the angled blade plate group, respectively. Nonunion occurred in four patients (20%) in the locking compression plates group (P=0.35). Conclusion: Based on having a larger valgus angle and mechanical lateral distal femoral angle correction in the angled blade plate group and considerable rate of nonunion in the locking compression plate group, the authors recommend using the angled blade plate for fixation of medial closing wedge supracondylar osteotomy for patients with valgus malalignment. However, more long-term studies are required. PMID:26894215
Disorders of the cerebellopontine angle
International Nuclear Information System (INIS)
Disorders of the cerebellopontine angle may present by symptoms like vertigo, hearing problems, affection of the trigeminal or facial nerve. Ipsilateral ataxia and contralateral hemiparesis develop in case of a rather large tumor in this region and display an involvement of the cerebellum and/or brainstem. However, some of these typical symptoms are not recognized by the patient. Thus, in case of a suspicion of a disorder of the cerebellopontine angle the relevant functions have to be tested clinically. In addition, electrophysiology can confirm dysfunction of these cranial nerves. Mainstay of the therapy should be the treatment of the underlying cause. Nevertheless, not seldom it is necessary to treat symptoms like vertigo or facial pain. (orig.)
DEFF Research Database (Denmark)
Jespersen, Søren Kragh; Wilhjelm, Jens Erik; Sillesen, Henrik
1998-01-01
This paper reports on a scanning technique, denoted multi-angle compound imaging (MACI), using spatial compounding. The MACI method also contains elements of frequency compounding, as the transmit frequency is lowered for the highest beam angles in order to reduce grating lobes. Compared to...... conventional B-mode imaging MACI offers better defined tissue boundaries and lower variance of the speckle pattern, resulting in an image with reduced random variations. Design and implementation of a compound imaging system is described, images of rubber tubes and porcine aorta are shown and effects on...... visualization are discussed. The speckle reduction is analyzed numerically and the results are found to be in excellent agreement with existing theory. An investigation of detectability of low-contrast lesions shows significant improvements compared to conventional imaging. Finally, possibilities for improving...
Determination of velocity vector angles using the directional cross-correlation method
DEFF Research Database (Denmark)
Kortbek, Jacob; Jensen, Jørgen Arendt
A method for determining both velocity magnitude and angle in any direction is suggested. The method uses focusing along the velocity direction and cross-correlation for finding the correct velocity magnitude. The angle is found from beamforming directional signals in a number of directions and...... then select the angle with the highest normalized correlation between directional signals. The approach is investigated using Field II simulations and data from the experimental ultrasound scanner RASMUS and with a parabolic flow having a peak velocity of 0.3 m/s. A 7 MHz linear array transducer is...... ( correlation-time ) between signals to correlate, and a proper choice varies with flow angle and flow velocity. One performance example is given with a fixed value of k tprf for all flow angles. The angle estimation on measured data for flow at 60 ◦ to 90 ◦ , yields a probability of valid estimates between 68...
International Nuclear Information System (INIS)
The design, functioning, and main calibration, characteristics of a wide-angle detector, capable of recording electrons with energies >= 8 keV and insensitive to u.v. solar radiation are described. A description of the sensor (electron trap) and its electronics in the analog (DEGAFOC) and counting (DEGAFOI) modes is given. Examples of telemetry recordings, illustrating the operation of the detector are included. (Auth.)
Method for Automated Bone Shape Correction within Bone Distraction Procedure
Blynskiy, F. Yu
2016-01-01
The method for automated bone shape correction within bone distraction procedure is presented. High precision deformation angle measurement is provided by the software for X- Ray images processing. Special BDC v.1.0.1. application is designed. The purpose of the BDC is modeling of the bone geometry structure to calculate the appropriate distraction forces. The correction procedure control is realized by the hardware of the distraction system.
Analysis and design of wide-angle foveated optical systems
Curatu, George
2009-12-01
The development of compact imaging systems capable of transmitting high-resolution images in real-time while covering a wide field-of-view (FOV) is critical in a variety of military and civilian applications: surveillance, threat detection, target acquisition, tracking, remote operation of unmanned vehicles, etc. Recently, optical foveated imaging using liquid crystal (LC) spatial light modulators (SLM) has received considerable attention as a potential approach to reducing size and complexity in fast wide-angle lenses. The fundamental concept behind optical foveated imaging is reducing the number of elements in a fast wide-angle lens by placing a phase SLM at the pupil stop to dynamically compensate aberrations left uncorrected by the optical design. In the recent years, considerable research and development has been conducted in the field of optical foveated imaging based on the LC SLM technology, and several foveated optical systems (FOS) prototypes have been built. However, most research has been focused so far on the experimental demonstration of the basic concept using off-the-shelf components, without much concern for the practicality or the optical performance of the systems. Published results quantify only the aberration correction capabilities of the FOS, often claiming diffraction-limited performance at the region of interest (ROI). However, these results have continually overlooked diffraction effects on the zero-order efficiency and the image quality. The research work presented in this dissertation covers the methods and results of a detailed theoretical research study on the diffraction analysis, image quality, design, and optimization of fast wide-angle FOSs based on the current transmissive LC SLM technology. The amplitude and phase diffraction effects caused by the pixelated aperture of the SLM are explained and quantified, revealing fundamental limitations imposed by the current transmissive LC SLM technology. As a part of this study, five
Holographic Thermalization with Weyl Corrections
Dey, Anshuman; Sarkar, Tapobrata
2015-01-01
We consider holographic thermalization in the presence of a Weyl correction in five dimensional AdS space. We numerically analyze the time dependence of the two point correlation functions and the expectation values of rectangular Wilson loops in the boundary field theory. The subtle interplay between the Weyl coupling constant and the chemical potential is studied in detail. An outcome of our analysis is the appearance of a swallow tail behaviour in the thermalization curve, and we give evidence that this might indicate distinct physical situations relating to different length scales in the problem.
High order QED corrections in Z physics
International Nuclear Information System (INIS)
In this thesis a number of calculations of higher order QED corrections are presented, all applying to the standard LEP/SLC processes e+e-→ f-bar f, where f stands for any fermion. In cases where f≠ e-, νe, the above process is only possible via annihilation of the incoming electron positron pair. At LEP/SLC this mainly occurs via the production and the subsequent decay of a Z boson, i.e. the cross section is heavily dominated by the Z resonance. These processes and the corrections to them, treated in a semi-analytical way, are discussed (ch. 2). In the case f = e- (Bhabha scattering) the process can also occur via the exchange of a virtual photon in the t-channel. Since the latter contribution is dominant at small scattering angles one has to exclude these angles if one is interested in Z physics. Having excluded that region one has to recalculate all QED corrections (ch. 3). The techniques introduced there enables for the calculation the difference between forward and backward scattering, the forward backward symmetry, for the cases f ≠ e-, νe (ch. 4). At small scattering angles, where Bhabha scattering is dominated by photon exchange in the t-channel, this process is used in experiments to determine the luminosity of the e+e- accelerator. hence an accurate theoretical description of this process at small angles is of vital interest to the overall normalization of all measurements at LEP/SLC. Ch. 5 gives such a description in a semi-analytical way. The last two chapters discuss Monte Carlo techniques that are used for the cases f≠ e-, νe. Ch. 6 describes the simulation of two photon bremsstrahlung, which is a second order QED correction effect. The results are compared with results of the semi-analytical treatment in ch. 2. Finally ch. 7 reviews several techniques that have been used to simulate higher order QED corrections for the cases f≠ e-, νe. (author). 132 refs.; 10 figs.; 16 tabs
OPTIMUM PROJECTION ANGLE FOR ATTAINING MAXIMUM DISTANCE IN A SOCCER PUNT KICK
Directory of Open Access Journals (Sweden)
Nicholas P. Linthorne
2011-03-01
Full Text Available To produce the greatest horizontal distance in a punt kick the ball must be projected at an appropriate angle. Here, we investigated the optimum projection angle that maximises the distance attained in a punt kick by a soccer goalkeeper. Two male players performed many maximum-effort kicks using projection angles of between 10° and 90°. The kicks were recorded by a video camera at 100 Hz and a 2 D biomechanical analysis was conducted to obtain measures of the projection velocity, projection angle, projection height, ball spin rate, and foot velocity at impact. The player's optimum projection angle was calculated by substituting mathematical equations for the relationships between the projection variables into the equations for the aerodynamic flight of a soccer ball. The calculated optimum projection angles were in agreement with the player's preferred projection angles (40° and 44°. In projectile sports even a small dependence of projection velocity on projection angle is sufficient to produce a substantial shift in the optimum projection angle away from 45°. In the punt kicks studied here, the optimum projection angle was close to 45° because the projection velocity of the ball remained almost constant across all projection angles. This result is in contrast to throwing and jumping for maximum distance, where the projection velocity the athlete is able to achieve decreases substantially with increasing projection angle and so the optimum projection angle is well below 45°.
... Prenatal Baby Bathing & Skin Care Breastfeeding Crying & Colic Diapers & Clothing Feeding & Nutrition Preemie Sleep Teething & Tooth Care Toddler Preschool Gradeschool Teen Young Adult Healthy Children > Ages & Stages > Baby > Preemie > Corrected Age ...
Attitudinally correct nomenclature
Cook, A C; Anderson, R. H.
2002-01-01
For half a century, inappropriate terms have been used to describe the various parts of the heart in a clinical context. Does the cardiological community have the fortitude to correct these mistakes?.
Nested Quantum Annealing Correction
Vinci, Walter; Albash, Tameem; Lidar, Daniel A.
2015-01-01
We present a general error-correcting scheme for quantum annealing that allows for the encoding of a logical qubit into an arbitrarily large number of physical qubits. Given any Ising model optimization problem, the encoding replaces each logical qubit by a complete graph of degree $C$, representing the distance of the error-correcting code. A subsequent minor-embedding step then implements the encoding on the underlying hardware graph of the quantum annealer. We demonstrate experimentally th...
Internal Extinction in Spiral Galaxies. Inclination Dependence
Magris, G. C.; Bruzual, G. A.
1987-05-01
. Kent (1986) finds that the surface brightness profiles (r) of spiral galaxies have a weak dependence, if any, on the inclination e with respect to the line of sight. This author also finds a correlation between the MIL ratio and the inclination of a galaxy. The lack of dependence of (r) in , = cos 8 indicates that the disk of these galaxies is optically thick ( .>l), due to the presence of dust grains. For an optically thick system o(r) a + 2.5 log . The cosecant law : 1.086 (Holmberg, 1975) does not explain the observed behaviour of a(r) with . 8ru'ual, Magris and Calvet (1986) solved the radiative transfer equation for a mixture of stars and dispersive dust grains distributed homogeneously in a plane parallel configuration, taking into account the wavelenght dependence of the albedo and , as well as the redistribution in angle of photons scattered by dust grains. The transfer equation is solved for the dimensionless intensity ?( , ) I( , )/I*, where 1* is the intensity emerging from the dust free configuration. The solution, CA -2.5 log (r..=0, ) , includes the correction to the galaxy magnitude due to the excess number 0+ stellar sources along the line o+ sigth (cc -i) with respect to the =I case (face on galaxy). For optically thick systems, does not depend on . The luminosity of a disk galaxy observed with inclination ,q 1 given in our model by L cc , from which log(M/L) = const + (.4 8.N( )'. with G.N . ) = -2.5 log( ). The constant is determined from the mass- luminosity. ratio of a dust free system. In terms of the correction (3(N) we can explain Kent's observations with values of between .3 and 4. These values are consistent with the observation of . -independent surface brightness profiles mentioned above. From this analysis we conclude that the correction terms of Bruzual, Magris and Calvet (1986), which take into account the dispersive properties of interstellar dust, can explain the behaviour of ar) and MIL with galaxy inclination. These correction
Energy Technology Data Exchange (ETDEWEB)
Chong, Le Roy [Changi General Hospital, Department of Radiology, Singapore (Singapore); Too, Chow Wei [Singapore General Hospital, Department of Diagnostic Radiology, Singapore (Singapore)
2014-03-15
To compare acetabular version angle measurements of CT scans in the prone and reformatted supine positions. CT acetabular version angle measurements have previously been done in the prone position to correct for pelvic tilt. With the advent of multidetector CT, recent studies have evaluated acetabular version angles measured in the supine position. To our knowledge, a comparison between these two approaches has not been performed. Case series in which consecutive CT urography studies of 49 adult patients performed in both prone and supine positions were retrospectively reviewed, and acetabular version angles of both hips measured. Retrospective review of 49 consecutive CT urography studies performed in both prone and supine positions was done, and acetabular version angles of both hips were measured. Two radiologists measured the acetabular version angles independently. Multiplanar reformation of the supine CT images was performed to compensate for pelvic tilt and rotation prior to angle measurements. There was excellent interobserver agreement between the two readers (ICC = 0.90). Acetabular version angle measurements from the prone CT images were larger compared to reformatted supine images (24.0 and 21.3 , respectively, p < 0.0001), with greater angles found in women. There was strong correlation between supine and prone acetabular version angle measurements with a Pearson correlation coefficient of 0.743. Acetabular version angles measured from prone and reformatted supine CT images show strong correlation but are significantly different with larger angles obtained from the former and in women; clinical implications of these findings may require further study in other to determine the best method of version angle measurement. CT acetabular version angle measurement is also reliable with excellent interobserver correlation. (orig.)
Static and Dynamic Contact Angles of Immersed Ferrofluid Droplets
Chatterjee, Souvick; Bhowmik, Dipanwita; Mukhopadhyay, Achintya; Ganguly, Ranjan
2013-11-01
Ferrofluid plug driven micro-pumps are useful for manipulating micro-volume of liquids by providing remote actuation using a localized magnetic field gradient. Inside a microchannel, the ferrofluid experiences combined actions of different relevant body forces. While the pressure, viscous and magnetic forces can be estimated using established techniques, the surface tension force requires information about the contact angle between the ferrofluid and glass capillary wall. We address this phenomenon through experimental characterization of static and dynamic contact angles of oil based ferrofluid (EFH3) droplets on glass surface immersed in pure or surfacted distilled water. The equilibrium static contact angle is found to significantly reduce in presence of a magnetic field. Dynamic contact angles are measured through high-speed imaging as the ferrofluid droplets slide along an inclined glass surface. Variation of contact angle hysteresis, which falls outside the Hoffmann Tanner equation for this case, is also investigated as a function of contact line velocity. A strong dependence is found between the contact angle hysteresis and the wetting time. Findings of the work is useful for designing ferrofluid plug-driven microfluidic plugs for different lab-on-a-chip applications.
Angle-Resolved Plasmonic Properties of Single Gold Nanorod Dimers
Institute of Scientific and Technical Information of China (English)
Jian Wu; Xuxing Lu; Qiannan Zhu; Junwei Zhao; Qishun Shen; Li Zhan; Weihai Ni
2014-01-01
Through wet-chemical assembly methods, gold nanorods were placed close to each other and formed a dimer with a gap distance*1 nm, and hence degenerated plasmonic dipole modes of individual nanorods coupled together to produce hybridized bonding and antibonding resonance modes. Previous studies using a condenser for illumination result in averaged signals over all excitation angles. By exciting an individual dimer obliquely at different angles, we demonstrate that these two new resonance modes are highly tunable and sensitive to the angle between the excitation polarization and the dimer orientation, which follows cos2u dependence. Moreover, for dimer structures with various structure angles, the resonance wavelengths as well as the refractive index sensitivities were found independent of the structure angle. Cal-culated angle-resolved plasmonic properties are in good agreement with the measurements. The assembled nanostructures investigated here are important for fundamental researches as well as potential applications when they are used as building blocks in plasmon-based optical and optoelectronic devices.
Operating experience with main blowers with variable blade angles
Energy Technology Data Exchange (ETDEWEB)
Bogatov, I.V.; Spivak, V.A.
1986-05-01
Efficiency of blowers used for ventilation in underground coal mines in the USSR in many cases is below the statistical efficiency level. Efficiency of 30% of blowers does not exceed 60%. New design of blower blades developed and tested in the USSR is an easy and economic way for increasing blower efficiency. Each blade consists of 2 sections: a stationary section and a section with a variable-incidence angle. The incidence angle depends on local conditions and requirements for ventilation. During performance tests of VTsZ-32 blowers in the PKAA mine an angle of blade incidence of 20 or 30 degrees was used. This guaranteed air pressure of 6,000 Pa and air output of 120 m/sup 3//s. Increased blade incidence angle was used in summer and during periods of increased methane emission. In winter angle of blade incidence was reduced to 10 degrees, blower output ranged from 80 to 90 m/sup 3//s, air pressure declined to 3,800 Pa. Using blower blades with variable-incidence angle reduced energy consumption, ventilation cost and investment.
Applying Contact Angle to a 2D Multiphase Smoothed Particle Hydrodynamics Model
Farrokhpanah, Amirsaman; Mostaghimi, Javad
2016-01-01
Equilibrium contact angle of liquid drops over horizontal surfaces has been modeled using Smoothed Particle Hydrodynamics (SPH). The model is capable of accurate implementation of contact angles to stationary and moving contact lines. In this scheme, the desired value for stationary or dynamic contact angle is used to correct the profile near the triple point. This is achieved by correcting the surface normals near the contact line and also interpolating the drop profile into the boundaries. Simulations show that a close match to the chosen contact angle values can be achieved for both stationary and moving contact lines. This technique has proven to reduce the amount of nonphysical shear stresses near the triple point and to enhance the convergence characteristics of the solver.
Adamczyk, L; Agakishiev, G; Aggarwal, M M; Ahammed, Z; Alekseev, I; Alford, J; Aparin, A; Arkhipkin, D; Aschenauer, E C; Averichev, G S; Banerjee, A; Bellwied, R; Bhasin, A; Bhati, A K; Bhattarai, P; Bielcik, J; Bielcikova, J; Bland, L C; Bordyuzhin, I G; Bouchet, J; Brandin, A V; Bunzarov, I; Burton, T P; Butterworth, J; Caines, H; S'anchez, M Calder'on de la Barca; campbell, J M; Cebra, D; Cervantes, M C; Chakaberia, I; Chaloupka, P; Chang, Z; Chattopadhyay, S; Chen, J H; Chen, X; Cheng, J; Cherney, M; Christie, W; Codrington, M J M; Contin, G; Crawford, H J; Das, S; De Silva, L C; Debbe, R R; Dedovich, T G; Deng, J; Derevschikov, A A; di Ruzza, B; Didenko, L; Dilks, C; Dong, X; Drachenberg, J L; Draper, J E; Du, C M; Dunkelberger, L E; Dunlop, J C; Efimov, L G; Engelage, J; Eppley, G; Esha, R; Evdokimov, O; Eyser, O; Fatemi, R; Fazio, S; Federic, P; Fedorisin, J; Feng,; Filip, P; Fisyak, Y; Flores, C E; Fulek, L; Gagliardi, C A; Garand, D; Geurts, F; Gibson, A; Girard, M; Greiner, L; Grosnick, D; Gunarathne, D S; Guo, Y; Gupta, S; Gupta, A; Guryn, W; Hamad, A; Hamed, A; Haque, R; Harris, J W; He, L; Heppelmann, S; Hirsch, A; Hoffmann, G W; Hofman, D J; Horvat, S; Huang, H Z; Huang, X; Huang, B; Huck, P; Humanic, T J; Igo, G; Jacobs, W W; Jang, H; Jiang, K; Judd, E G; Kabana, S; Kalinkin, D; Kang, K; Kauder, K; Ke, H W; Keane, D; Kechechyan, A; Khan, Z H; Kikola, D P; Kisel, I; Kisiel, A; Klein, S R; Koetke, D D; Kollegger, T; Kosarzewski, L K; Kotchenda, L; Kraishan, A F; Kravtsov, P; Krueger, K; Kulakov, I; Kumar, L; Kycia, R A; Lamont, M A C; Landgraf, J M; Landry, K D; Lauret, J; Lebedev, A; Lednicky, R; Lee, J H; Li, X; Li, W; Li, Z M; Li, Y; Li, C; Lisa, M A; Liu, F; Ljubicic, T; Llope, W J; Lomnitz, M; Longacre, R S; Luo, X; Ma, L; Ma, R; Ma, G L; Ma, Y G; Magdy, N; Majka, R; Manion, A; Margetis, S; Markert, C; Masui, H; Matis, H S; McDonald, D; Meehan, K; Minaev, N G; Mioduszewski, S; Mohanty, B; Mondal, M M; Morozov, D A; Mustafa, M K; Nandi, B K; Nasim, Md; Nayak, T K; Nigmatkulov, G; Nogach, L V; Noh, S Y; Novak, J; Nurushev, S B; Odyniec, G; Ogawa, A; Oh, K; Okorokov, V; Olvitt, D L; Page, B S; Pan, Y X; Pandit, Y; Panebratsev, Y; Pawlak, T; Pawlik, B; Pei, H; Perkins, C; Peterson, A; Pile, P; Planinic, M; Pluta, J; Poljak, N; Poniatowska, K; Porter, J; Posik, M; Poskanzer, A M; Pruthi, N K; Putschke, J; Qiu, H; Quintero, A; Ramachandran, S; Raniwala, R; Raniwala, S; Ray, R L; Ritter, H G; Roberts, J B; Rogachevskiy, O V; Romero, J L; Roy, A; Ruan, L; Rusnak, J; Rusnakova, O; Sahoo, N R; Sahu, P K; Sakrejda, I; Salur, S; Sandacz, A; Sandweiss, J; Sarkar, A; Schambach, J; Scharenberg, R P; Schmah, A M; Schmidke, W B; Schmitz, N; Seger, J; Seyboth, P; Shah, N; Shahaliev, E; Shanmuganathan, P V; Shao, M; Sharma, M K; Sharma, B; Shen, W Q; Shi, S S; Shou, Q Y; Sichtermann, E P; Sikora, R; Simko, M; Skoby, M J; Smirnov, N; Smirnov, D; Solanki, D; Song, L; Sorensen, P; Spinka, H M; Srivastava, B; Stanislaus, T D S; Stock, R; Strikhanov, M; Stringfellow, B; Sumbera, M; Summa, B J; Sun, Y; Sun, Z; Sun, X M; Sun, X; Surrow, B; Svirida, D N; Szelezniak, M A; Takahashi, J; Tang, A H; Tang, Z; Tarnowsky, T; Tawfik, A N; Thomas, J H; Timmins, A R; Tlusty, D; Tokarev, M; Trentalange, S; Tribble, R E; Tribedy, P; Tripathy, S K; Trzeciak, B A; Tsai, O D; Ullrich, T; Underwood, D G; Upsal, I; Van Buren, G; van Nieuwenhuizen, G; Vandenbroucke, M; Varma, R; Vasiliev, A N; Vertesi, R; Videbæk, F; Viyogi, Y P; Vokal, S; Voloshin, S A; Vossen, A; Wang, Y; Wang, F; Wang, H; Wang, J S; Wang, G; Webb, J C; Webb, G; Wen, L; Westfall, G D; Wieman, H; Wissink, S W; Witt, R; Wu, Y F; Xiao, Z; Xie, W; Xin, K; Xu, Z; Xu, Q H; Xu, N; Xu, H; Xu, Y F; Yang, Y; Yang, C; Yang, S; Yang, Q; Ye, Z; Yepes, P; Yi, L; Yip, K; Yoo, I -K; Yu, N; Zbroszczyk, H; Zha, W; Zhang, J B; Zhang, X P; Zhang, S; Zhang, J; Zhang, Z; Zhang, Y; Zhang, J L; Zhao, F; Zhao, J; Zhong, C; Zhou, L; Zhu, X; Zoulkarneeva, Y; Zyzak, M
2015-01-01
The acceptance-corrected dielectron excess mass spectra, where the known hadronic sources have been subtracted from the inclusive dielectron mass spectra, are reported for the first time at mid-rapidity $|y_{ee}|<1$ in minimum-bias Au+Au collisions at $\\sqrt{s_{NN}}$ = 19.6 and 200 GeV. The excess mass spectra are consistently described by a model calculation with a broadened $\\rho$ spectral function for $M_{ee}<1.1$ GeV/$c^{2}$. The integrated dielectron excess yield at $\\sqrt{s_{NN}}$ = 19.6 GeV for $0.4
Directory of Open Access Journals (Sweden)
L. Adamczyk
2015-11-01
Full Text Available The acceptance-corrected dielectron excess mass spectra, where the known hadronic sources have been subtracted from the inclusive dielectron mass spectra, are reported for the first time at mid-rapidity |yee|<1 in minimum-bias Au+Au collisions at sNN=19.6 and 200 GeV. The excess mass spectra are consistently described by a model calculation with a broadened ρ spectral function for Mee<1.1 GeV/c2. The integrated dielectron excess yield at sNN=19.6 GeV for 0.4
Small angle scattering and polymers
International Nuclear Information System (INIS)
The determination of polymer structure is a problem of interest for both statistical physics and industrial applications. The average polymer structure is defined. Then, it is shown why small angle scattering, associated with isotopic substitution, is very well suited to the measurement of the chain conformation. The corresponding example is the old, but pedagogic, measurement of the chain form factor in the polymer melt. The powerful contrast variation method is illustrated by a recent determination of the concentration profile of a polymer interface. (author) 12 figs., 48 refs
Opening Angles of Collapsar Jets
Mizuta, Akira; Ioka, Kunihito
2013-01-01
We investigate the jet propagation and breakout from the stellar progenitor for gamma-ray burst (GRB) collapsars by performing two-dimensional relativistic hydrodynamic simulations and analytical modeling. We find that the jet opening angle is given by $\\theta_j \\sim 1/5 \\Gamma_{0}$, and infer the initial Lorentz factor of the jet at the central engine, $\\Gamma_0$, is a few for existing observations of $\\theta_j$. The jet keeps the Lorentz factor low inside the star by converging cylindricall...
Small angle scattering and polymers
Energy Technology Data Exchange (ETDEWEB)
Cotton, J.P. [Laboratoire Leon Brillouin (LLB) - Centre d`Etudes de Saclay, 91 - Gif-sur-Yvette (France)
1996-12-31
The determination of polymer structure is a problem of interest for both statistical physics and industrial applications. The average polymer structure is defined. Then, it is shown why small angle scattering, associated with isotopic substitution, is very well suited to the measurement of the chain conformation. The corresponding example is the old, but pedagogic, measurement of the chain form factor in the polymer melt. The powerful contrast variation method is illustrated by a recent determination of the concentration profile of a polymer interface. (author) 12 figs., 48 refs.
Multitemporal evaluation of topographic correction methods using multispectral synthetic images
Directory of Open Access Journals (Sweden)
I. Sola
2014-06-01
Full Text Available This paper presents a multitemporal evaluation of topographic correction (TOC methods based on synthetically generated images in order to evaluate the influence of solar angles on the performance of TOC methods. These synthetic images represent the radiance an optical sensor would receive for different periods of the year considering the real topography (SR image, and considering the relief completely horizontal (SH image. The comparison between the corrected image obtained applying a TOC method to a SR image and the SH image of the same area, i.e. considered the ideal correction, allows assessing the performance of each TOC algorithm, quantitatively measured through the Structural Similarity Index (SSIM.
Screening corrections to the Rutherford cross section
International Nuclear Information System (INIS)
Differential cross sections for elastic p-Au scattering were measured in the energy range between 0.2 and 0.8 MeV for scattering angles from 300 to 1500 in order to determine corrections to the Rutherford cross section due to the screening of the nuclear charge by the atomic electrons. Furthermore, differential cross sections have been calculated in the weakly screening region using various screening functions. A simple analytical expression has been derived for the representation of both experimental and theoretical results. (orig.)
Calculation of small angle multiple scattering and the application in proton beam tomography
International Nuclear Information System (INIS)
This paper discuss an expression for the determination of the multiple scattering angle when the energy loss is not considered, from the small angle multiple scattering. Also, it is discussed a correction for the standard formula of the multiple scattering angle presented by Rossi. The values of these correction factor were obtained for protons and alpha particles and heavy ions. These results show that the correction factor is important for protons and alpha particles, but irrelevant for heavy ions with mass number at the interval of 12 to 40 a mu. The angles of scattering angle and lateral displacement were calculated for a proton beam resting on on targets with homogeneous material such as water, which has great applicability for comparison with biological systems, wi the energy interval ranging from 180 to 250 MeV, which is the interest region for tomography with proton beams (pCT). From the results it became evident that for protons, the correction of energy in each space for gross targets must be considered. This work is part of a study which try perform a formalism for reconstruction of images obtained through a prototype of proton beam tomography
Hybrid scatter correction for CT imaging
International Nuclear Information System (INIS)
The purpose of this study was to develop and evaluate the hybrid scatter correction algorithm (HSC) for CT imaging. Therefore, two established ways to perform scatter correction, i.e. physical scatter correction based on Monte Carlo simulations and a convolution-based scatter correction algorithm, were combined in order to perform an object-dependent, fast and accurate scatter correction. Based on a reconstructed CT volume, patient-specific scatter intensity is estimated by a coarse Monte Carlo simulation that uses a reduced amount of simulated photons in order to reduce the simulation time. To further speed up the Monte Carlo scatter estimation, scatter intensities are simulated only for a fraction of all projections. In a second step, the high noise estimate of the scatter intensity is used to calibrate the open parameters in a convolution-based algorithm which is then used to correct measured intensities for scatter. Furthermore, the scatter-corrected intensities are used in order to reconstruct a scatter-corrected CT volume data set. To evaluate the scatter reduction potential of HSC, we conducted simulations in a clinical CT geometry and measurements with a flat detector CT system. In the simulation study, HSC-corrected images were compared to scatter-free reference images. For the measurements, no scatter-free reference image was available. Therefore, we used an image corrected with a low-noise Monte Carlo simulation as a reference. The results show that the HSC can significantly reduce scatter artifacts. Compared to the reference images, the error due to scatter artifacts decreased from 100% for uncorrected images to a value below 20% for HSC-corrected images for both the clinical (simulated data) and the flat detector CT geometry (measurement). Compared to a low-noise Monte Carlo simulation, with the HSC the number of photon histories can be reduced by about a factor of 100 per projection without losing correction accuracy. Furthermore, it was sufficient to
Improving gated cardiac scanning using limited-angle reconstruction technique
International Nuclear Information System (INIS)
Selected phases of the cardiac cycle can be imaged by the method of gated cardiac scanning using whole body scanners. However, since there is no synchronization between the random heart beats and the CT machine, the output will have gaps in the angular coverage of each scan. The missing projections in these gaps result in artifacts in the reconstructed images. In this paper, the technique of limited-angle reconstruction is employed to fill in the missing projections to remove the artifacts. The object is transformed back and forth between the object space and the projection space, being corrected in each step by the constraints of the finite spatial extent and of the upper and lower bounds of the object in the object space, and the known projections in the projection space. It is found that by using the proposed algorithm the rms errors of the limited-angle images are reduced to a level comparable to those of the complete-angle images. The same iteration algorithm can also be used to reduce the fan beam scanning angle from 360 degree to 180 degree without sacrificing much image quality
Combined surgical management of mandibular angle prominence and microgenia
International Nuclear Information System (INIS)
Chin play a very important role in facial aesthetics. Different deformities of volume and of position may occur at this level and it is the microgenia one of the more frequent. Treatment options include the use of silicone, alloplasty materials and autologous bone graft. Authors report the use of the bone removed from mandibular angle to increase the chin. This is the case of a white female patient aged 18 seen by the Orthognathics Multidisciplinary Staff of 'V. I. Lenin' Hospital due to its uncommon face width. The corresponding physical examination as well as the complementary ones diagnosed a bilateral prominence of mandibular angle associated with a microgenia. Surgery carried out was of remodeling type of both mandibular angles and genioplasty of height increase and a discrete advancement using the bone removed from the gonion. There were satisfactory aesthetic results without evidence of bone reabsorption. We conclude that use of autologous graft of mandibular angle is an effective treatment alternative for correction of microgenia. (author)
Measurement of the CKM angle $\\gamma$ at LHCb
Gersabeck, M
2009-01-01
The precise measurement of the CKM unitarity triangle angle $\\gamma$ is a key goal of the LHCb physics programme. The uncertainty on $\\gamma$, the currently least-well known of the three angles, will be reduced dramatically. Complementary measurements will be made in tree-level processes, and modes where loop diagrams play an important role. The tree-level measurements will cover time-integrated as well as time- dependent measurements in both the $B^0_d$ and the $B^0_s$ sectors. The ensemble of these measurements will provide a powerful test of whether new physics phases contribute to heavy-flavour transitions.
Angle of Arrival Detection with Fifth Order Phase Operators
Khmou, Youssef
2015-01-01
In this paper, a fifth order propagator operators are proposed for estimating the Angles Of Arrival (AOA) of narrowband electromagnetic waves impinging on antenna array when its number of sensors is larger than the number of radiating sources. The array response matrix is partitioned into five linearly dependent phases to construct the noise projector using five different propagators from non diagonal blocks of the spectral matrice of the received data; hence, five different estimators are proposed to estimate the angles of the sources. The simulation results proved the performance of the proposed estimators in the presence of white noise comparatively to high resolution eigen based spectra.
Small-angle neutron-scattering experiments
International Nuclear Information System (INIS)
A brief introduction to small-angle scattering (SAS) is given. Initial results obtained using the AERE small-angle diffractometer are presented for four materials of interest: doped uranium dioxide, nitrided steel, graphite and alumina. (U.K.)
The Complex Angle in Normed Spaces
International Nuclear Information System (INIS)
We consider a generalized angle in complex normed vector spaces. Its definition corresponds to the definition of the well known Euclidean angle in real inner product spaces. Not surprisingly it yields complex values as 'angles'. This 'angle' has some simple properties, which are known from the usual angle in real inner product spaces. But to do ordinary Euclidean geometry real angles are necessary. We show that even in a complex normed space there are many pure real valued 'angles'. The situation improves yet in inner product spaces. There we can use the known theory of orthogonal systems to find many pairs of vectors with real angles, and to do geometry which is based on the Greeks 2000 years ago
An Angle Criterion for Riesz Bases
DEFF Research Database (Denmark)
Lindner, Alexander M; Bittner, B.
We present a characterization of Riesz bases in terms ofthe angles between certain finite dimensional subspaces. Correlationsbetween the bounds of the Riesz basis and the size of the angles arederived....
Model Correction Factor Method
DEFF Research Database (Denmark)
Christensen, Claus; Randrup-Thomsen, Søren; Morsing Johannesen, Johannes
1997-01-01
of the model correction factor method, is that in simpler form not using gradient information on the original limit state function or only using this information once, a drastic reduction of the number of limit state evaluation is obtained together with good approximations on the reliability. Methods......The model correction factor method is proposed as an alternative to traditional polynomial based response surface techniques in structural reliability considering a computationally time consuming limit state procedure as a 'black box'. The class of polynomial functions is replaced by a limit...... statebased on an idealized mechanical model to be adapted to the original limit state by the model correction factor. Reliable approximations are obtained by iterative use of gradient information on the original limit state function analogously to previous response surface approaches. However, the strength...
Correction of vignetting and distortion errors induced by two-axis light beam steering
Gao, Liang; Tkaczyk, Tomasz S.
2012-01-01
A mirror facet’s angle correction approach is presented for eliminating pupil plane distortions and sub-field image vignetting in the image mapping spectrometry (IMS). The two-axis light reflection problem on the image mapper is solved and a rigorous analytical solution is provided. The cellular fluorescence imaging experiment demonstrates that, with an angle-corrected image mapper, the acquired image quality of spectral channels has been significantly improved compared to previous IMS images...
Atmospheric Reentry Dispersion Correction Ascent Phase Guidance for a Generic Reentry Vehicle
Directory of Open Access Journals (Sweden)
Avinash Chander
2013-05-01
Full Text Available Launch vehicle explicit guidance mechanism depends on the estimation of the desired burnout conditions and driving the vehicle to achieve these conditions. The accuracy of the vehicle at the target point depends on how tightly these conditions are achieved and what is the strategy used to define the trajectory. It has been observed inthe literature that most of the guidance mechanisms during reentry use vacuum guidance equations that is durin greentry the atmospheric effects are not considered. In order to achieve minimum miss distance at the target point theat mospheric effects are to be considered during the guided phase and appropriate corrections should be executed,otherwise depending on the reentry flight path angle and ballistic coefficient the errors can be as high as tens of nautical miles. In this paper, the authors develop a novel approach to these vacuum guided launch vehicle problems.The paper elaborates how to calculate a prior the reentry dispersion during the ascent phase guidance and provide guidance corrections such that the terminal conditions are achieved with higher accuracy.Defence Science Journal, 2013, 63(3, pp.233-241, DOI:http://dx.doi.org/10.14429/dsj.63.3733
Contact angle and film pressure: study of a talc surface.
Douillard, J M; Zajac, J; Malandrini, H; Clauss, F
2002-11-15
Talc samples in both sheet and powder form are studied by adsorption calorimetry and adsorption isotherm techniques. A model is used to determine the solid surface energy, the solid surface tension and the dispersive, acidic, and basic components of these terms. These results are introduced in an approximate equation relating adsorption to contact angle data. Experimental contact angles are in correct agreement with this approach. The Neumann equation of state is used to fit the data and discussed. It appears as a numerical form of the general equation taking into account gas adsorption and film pressure. Behaviors of talc in contact with liquids do not appear very different whether the solid is in sheet or powder form. PMID:12505082
Scattering angle base filtering of the inversion gradients
Alkhalifah, Tariq Ali
2014-01-01
Full waveform inversion (FWI) requires a hierarchical approach based on the availability of low frequencies to maneuver the complex nonlinearity associated with the problem of velocity inversion. I develop a model gradient filter to help us access the parts of the gradient more suitable to combat this potential nonlinearity. The filter is based on representing the gradient in the time-lag normalized domain, in which low scattering angles of the gradient update are initially muted. The result are long-wavelength updates controlled by the ray component of the wavefield. In this case, even 10 Hz data can produce near zero wavelength updates suitable for a background correction of the model. Allowing smaller scattering angle to contribute provides higher resolution information to the model.
The qualitative criterion of transient angle stability
Lyu, R; Xue, Y.; Xue, F; Wu, Qiuwei; Yang, Guangya; Zhou, H; Ju, P.
2015-01-01
In almost all the literatures, the qualitative assessment of transient angle stability extracts the angle information of generators based on the swing curve. As the angle (or angle difference) of concern and the threshold value rely strongly on the engineering experience, the validity and robust of these criterions are weak. Based on the stability mechanism from the extended equal area criterion (EEAC) theory and combining with abundant simulations of real system, this paper analyzes the crit...
Explicit angle structures for veering triangulations
Futer, David
2010-01-01
Agol recently introduced the notion of a veering triangulation, and showed that such triangulations naturally arise as layered triangulations of fibered hyperbolic 3-manifolds. We prove, by a constructive argument, that every veering triangulation admits positive angle structures, recovering a result of Hodgson, Rubinstein, Segerman, and Tillmann. Our construction leads to explicit lower bounds on the smallest angle in this positive angle structure, and to information about angled holonomy of the boundary tori.
Azimuth and angle gathers from wave equation imaging in VTI media
Alkhalifah, Tariq Ali
2009-01-01
Angles in common-image angle domain gathers refer to the scattering angle at the reflector and provide a natural access to analyzing migration velocities and amplitudes. In the case of anisotropic media, the importance of angle gathers is enhanced by the need to properly estimate multiple anisotropic parameters for a proper representation of the medium. We extract angle gathers for each downward-continuation step from converting offset-space-frequency planes into angle-space planes simultaneously with applying the imaging condition in a transversely isotropic (VTI) medium. The analytic equations, though cumbersome, are exact within the framework of the acoustic approximation. They are also easily programmable and show that angle gather mapping in the case anisotropic media differs from its isotropic counterpart, difference depending mainly on the strength of anisotropy.
International Nuclear Information System (INIS)
For the practical application of the method proposed by J. Bryant, the authors carried out a series of small corrections, related with the bottom, the dead time of the detectors and channels, with the resolution time of the coincidences, with the accidental coincidences, with the decay scheme and with the gamma efficiency of the beta detector beta and the beta efficiency beta of the gamma detector. The calculation of the correction formula is presented in the development of the present report, being presented 25 combinations of the probability of the first existent state at once of one disintegration and the second state at once of the following disintegration. (Author)
Directory of Open Access Journals (Sweden)
Kim,Eugene
2009-12-01
Full Text Available Conventionally, the carrying angle of the elbow is measured using simple two-dimensional radiography or goniometry, which has questionable reliability. This study proposes a novel method for estimating carrying angles using computed tomography that can enhance the reliability of the angle measurement. Data of CT scans from 25 elbow joints were processed to build segmented three-dimensional models. The cross-sectional centerlines of the ulna and the humerus were traced from the 3D models, and the angle between 2 vectors formed from the centerlines of the humerus and the ulna was defined as the "three-dimensional carrying angle." These angles were compared with those measured by simple radiograph. Two cases of angular deformity were underwent surgery based on this preoperative surgical planning, and the postoperative 3D carrying angles were evaluated using the proposed method. The mean value of the calculated three-dimensional carrying angle was 20.7 degrees +/-3.61, while it was 16.3 degrees +/-3.21 based on simple radiography without statistical difference. Based on the 3D carrying angle estimations, 2 surgical cases of cubitus deformities were planned by comparison with the normal contra-lateral elbow. Postoperative angle estimations confirmed that the corrected angles were nearly identical to the planned angles for both cases. The results of this study showed that the carrying angle can be accurately estimated using three-dimensional CT and that the proposed method is useful in evaluating deformities of the elbow with high reliability.
Atmospheric Error Correction of the Laser Beam Ranging
Directory of Open Access Journals (Sweden)
J. Saydi
2014-01-01
Full Text Available Atmospheric models based on surface measurements of pressure, temperature, and relative humidity have been used to increase the laser ranging accuracy by ray tracing. Atmospheric refraction can cause significant errors in laser ranging systems. Through the present research, the atmospheric effects on the laser beam were investigated by using the principles of laser ranging. Atmospheric correction was calculated for 0.532, 1.3, and 10.6 micron wavelengths through the weather conditions of Tehran, Isfahan, and Bushehr in Iran since March 2012 to March 2013. Through the present research the atmospheric correction was computed for meteorological data in base of monthly mean. Of course, the meteorological data were received from meteorological stations in Tehran, Isfahan, and Bushehr. Atmospheric correction was calculated for 11, 100, and 200 kilometers laser beam propagations under 30°, 60°, and 90° rising angles for each propagation. The results of the study showed that in the same months and beam emission angles, the atmospheric correction was most accurate for 10.6 micron wavelength. The laser ranging error was decreased by increasing the laser emission angle. The atmospheric correction with two Marini-Murray and Mendes-Pavlis models for 0.532 nm was compared.
Study of tip loss corrections using CFD rotor computations
Shen, W. Z.; Zhu, W. J.; Sørensen, J. N.
2014-12-01
Tip loss correction is known to play an important role for engineering prediction of wind turbine performance. There are two different types of tip loss corrections: tip corrections on momentum theory and tip corrections on airfoil data. In this paper, we study the latter using detailed CFD computations for wind turbines with sharp tip. Using the technique of determination of angle of attack and the CFD results for a NordTank 500 kW rotor, airfoil data are extracted and a new tip loss function on airfoil data is derived. To validate, BEM computations with the new tip loss function are carried out and compared with CFD results for the NordTank 500 kW turbine and the NREL 5 MW turbine. Comparisons show that BEM with the new tip loss function can predict correctly the loading near the blade tip.
Study of tip loss corrections using CFD rotor computations
International Nuclear Information System (INIS)
Tip loss correction is known to play an important role for engineering prediction of wind turbine performance. There are two different types of tip loss corrections: tip corrections on momentum theory and tip corrections on airfoil data. In this paper, we study the latter using detailed CFD computations for wind turbines with sharp tip. Using the technique of determination of angle of attack and the CFD results for a NordTank 500 kW rotor, airfoil data are extracted and a new tip loss function on airfoil data is derived. To validate, BEM computations with the new tip loss function are carried out and compared with CFD results for the NordTank 500 kW turbine and the NREL 5 MW turbine. Comparisons show that BEM with the new tip loss function can predict correctly the loading near the blade tip
30 CFR 56.19037 - Fleet angles.
2010-07-01
... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Fleet angles. 56.19037 Section 56.19037 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND... Sheaves § 56.19037 Fleet angles. Fleet angles on hoists installed after November 15, 1979, shall not...