Статті в журналах: "Asymmetric profiles"

1

Deg, N., S.-L. Blyth, N. Hank, S. Kruger, and C. Carignan. "Systematically asymmetric: a comparison of H i profile asymmetries in real and simulated galaxies." Monthly Notices of the Royal Astronomical Society 495, no. 2 (May 18, 2020): 1984–2001. http://dx.doi.org/10.1093/mnras/staa1368.

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ABSTRACT We examine different measures of asymmetry for galaxy H i velocity profiles. We introduce the channel-by-channel asymmetry and the velocity-of-equality statistics to quantify profile asymmetries. Using a sample of simulated galaxies, we examine how these and the standard lopsidedness morphometric statistic depend on a variety of observational effects, including the viewing angle and inclination. We find that our newly introduced channel-by-channel asymmetry is less sensitive to the effects of viewing angle and inclination than other morphometrics. Applying our statistics to the WHISP (Westerbork H i survey of Irregular and SPiral galaxies) H i galaxy sample, we also find that the channel-by-channel asymmetry is a better indicator of visually classified asymmetric profiles. In addition, we find that the lopsidedness–velocity of equality space can be used to identify profiles with deep central dips without visual inspection.

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2

Manuwal, Aditya, Aaron D. Ludlow, Adam R. H. Stevens, Ruby J. Wright, and Aaron S. G. Robotham. "Drivers of asymmetry in synthetic H i emission-line profiles of galaxies in the eagle simulation." Monthly Notices of the Royal Astronomical Society 510, no. 3 (December 4, 2021): 3408–29. http://dx.doi.org/10.1093/mnras/stab3534.

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ABSTRACT We study the shapes of spatially integrated $\rm{H}\, \small {{I}}$ emission-line profiles of galaxies in the eagle simulation using three separate measures of the profile’s asymmetry. We show that the subset of eagle galaxies whose gas fractions and stellar masses are consistent with those in the xGASS survey also have similar $\rm{H}\, \small {{I}}$ line asymmetries. Central galaxies with symmetric $\rm{H}\, \small {{I}}$ line profiles typically correspond to rotationally supported $\rm{H}\, \small {{I}}$ and stellar discs, but those with asymmetric line profiles may or may not correspond to dispersion-dominated systems. Galaxies with symmetric $\rm{H}\, \small {{I}}$ emission lines are, on average, more gas rich than those with asymmetric lines, and also exhibit systematic differences in their specific star formation rates, suggesting that turbulence generated by stellar or AGN feedback may be one factor contributing to $\rm{H}\, \small {{I}}$ line asymmetry. The line asymmetry also correlates strongly with the dynamical state of a galaxy’s host dark matter halo: older, more relaxed haloes host more-symmetric galaxies than those hosted by unrelaxed ones. At fixed halo mass, asymmetric centrals tend to be surrounded by a larger number of massive subhaloes than their symmetric counterparts, and also experience higher rates of gas accretion and outflow. At fixed stellar mass, central galaxies have, on average, more symmetric $\rm{H}\, \small {{I}}$ emission lines than satellites; for the latter, ram pressure and tidal stripping are significant sources of asymmetry.

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3

Kulkarni, P., and D. Dutta. "An Investigation of Techniques for Asymmetry Rectification." Journal of Mechanical Design 117, no. 4 (December 1, 1995): 620–26. http://dx.doi.org/10.1115/1.2826730.

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This paper is concerned with symmetry and asymmetry in objects. Earlier studies on the subject have dealt with the detection of symmetry. We study the problem of asymmetry rectification, i.e., given an asymmetric profile, suggest geometric changes to make it symmetric. We have investigated two techniques for asymmetry rectification. This paper reports on the techniques and the results. First, we analyze the problem using skeleton representations and propose a simple algorithm for rectifying asymmetric convex profiles. Next, we outline an optimization scheme for the rectification of convex and nonconvex profiles, in 2D and 3D. Implemented examples are presented for both algorithms.

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4

Badel, Anne, Laëtitia Breuil, Pierre Laville, and Leslie Regad. "Exploration of the Structural Asymmetry Induced by the Intrinsic Flexibility of HIV-2 Protease." Symmetry 14, no. 2 (February 11, 2022): 362. http://dx.doi.org/10.3390/sym14020362.

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HIV-2 protease (PR2) is a homodimer targeted by drugs in the treatment of HIV-2 infections. This dimer is often considered symmetric. However, exploration of crystallographic structures showed that the two chains of PR2 exhibit different conformations. This study presents the first analysis of the structural asymmetry of PR2 induced by its intrinsic flexibility. We followed the structural asymmetry of PR2 throughout a molecular dynamics (MD) simulation of 1 microsecond. To do so, we quantified the global and local structural asymmetries of 1001 structures extracted from the MD simulation using the root mean square deviation (RMSD) between the two chains in each structure. We then analyzed the links between global and local asymmetry and PR2 flexibility. Our results showed that the global asymmetry of PR2 evolves over time and that it is not explained by the asymmetry of only one region of PR2. We noted that the most flexible regions of PR2 are the most asymmetric regions, revealing that the structural asymmetry of a region is induced by its intrinsic flexibility. Using multivariate analysis methods, we identified six asymmetric profiles varying from structures exhibiting weak asymmetry to structures with extreme asymmetry in at least eight different regions. The analysis of transitions between the different profiles in the MD simulation showed that two consecutive structures often exhibit similar asymmetric profiles, revealing small deformations. To conclude, this study provides insights which help to better understand PR2’s structure, dynamics, and deformations.

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5

Ida, T., H. Hibino, and H. Toraya. "Deconvolution of instrumental aberrations for synchrotron powder X-ray diffractometry." Journal of Applied Crystallography 36, no. 2 (March 15, 2003): 181–87. http://dx.doi.org/10.1107/s0021889802021131.

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A method to remove the effects of instrumental aberrations from the whole powder diffraction pattern measured with a high-resolution synchrotron powder diffractometer is presented. Two types of asymmetry in the peak profiles caused by (i) the axial-divergence aberration of the diffractometer (diffractometer aberration) and (ii) the aberration of the monochromator and focusing optics on the beamline (beamline aberration) are both taken into account. The method is based on the whole-pattern deconvolution by Fourier technique combined with the abscissa-scale transformation appropriate for each instrumental aberration. The experimental powder diffraction data of LaB6(NIST SRM660) measured on beamline BL-4B2at the Photon Factory in Tsukuba have been analysed by the method. The formula of the scale transformation for the diffractometer aberration hasa prioribeen derived from the instrumental function with geometric parameters of the optics. The strongly deformed experimental peak profiles at low diffraction angles have been transformed to sharp peak profiles with less asymmetry by the deconvolution of the diffractometer aberration. The peak profiles obtained by the deconvolution of the diffractometer aberration were modelled by an asymmetric model profile function synthesized by the convolution of the extended pseudo-Voigt function and an asymmetric component function with an empirical asymmetry parameter, which were linearly dependent on the diffraction angle. Fairly symmetric peak profiles have been obtained by further deconvolution of the empirically determined asymmetric component of the beamline aberration.

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6

STRITE, DANIEL, PAUL J. MASSMAN, NORMA COOKE, and RACHELLE S. DOODY. "Neuropsychological asymmetry in Alzheimer's disease: Verbal versus visuoconstructional deficits across stages of dementia." Journal of the International Neuropsychological Society 3, no. 5 (September 1997): 420–27. http://dx.doi.org/10.1017/s1355617797004207.

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The incidence of clinically apparent asymmetric profiles of neuropsychological deficits in Alzheimer's disease (AD) patients similar to those reported in the PET literature is currently unclear. This study investigated lateral neuropsychological asymmetry using principal component factor analysis in a sample of 153 patients diagnosed with probable AD. Using factor scores, patients were classified into groups exhibiting asymmetric or symmetric profiles of neuropsychological deficits. In the analysis of lateral asymmetry, 27.5% of patients were classified as asymmetric (10% verbally and 17% visuospatially). Consistent with reports of continued asymmetry beyond the mild dementia stage, asymmetry was exhibited in the mild, moderate, and severely demented groups. These findings of neuropsychological asymmetry across stages of dementia are consistent with the picture of significant neuropsychological heterogeneity in AD that has been emerging in the decade. (JINS, 1997, 3, 420–427.)

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7

Watts, Adam B., Chris Power, Barbara Catinella, Luca Cortese, and Adam R. H. Stevens. "Global H i asymmetries in IllustrisTNG: a diversity of physical processes disturb the cold gas in galaxies." Monthly Notices of the Royal Astronomical Society 499, no. 4 (October 15, 2020): 5205–19. http://dx.doi.org/10.1093/mnras/staa3200.

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ABSTRACT Observations of the cold neutral atomic hydrogen (H i) in and around disc galaxies have revealed that spatial and kinematic asymmetries are common place, and are reflected in the global H i spectra. We use the TNG100 box from the IllustrisTNG suite of cosmological simulations to study the conditions under which these asymmetries may arise in current theoretical galaxy formation models. We find that more than 50 per cent of the sample has at least a 10 per cent difference in integrated flux between the high- and low-velocity half of the spectrum, thus the typical TNG100 galaxy has an H i profile that is not fully symmetric. We find that satellite galaxies are a more asymmetric population than centrals, consistent with observational results. Using halo mass as a proxy for environment, this trend appears to be driven by the satellite population within the virial radius of haloes more massive than 1013 M⊙, typical of medium/large groups. We show that, while the excess of H i asymmetry in group satellites is likely driven by ram pressure, the bulk of the asymmetric H i profiles observed in TNG100 are driven by physical processes able to affect both the central and satellite populations. Our results highlight how asymmetries are not driven solely by environment, and multiple physical processes can produce the same asymmetric shape in global H i spectra.

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8

Rao, K. Sreenivasa, G. E. Babu, P. Ravi kumar, M. Anusha, A. Saiprashad, and P. Kiran Babu. "Validation and Profile Modification of a Spur Gear to Improve the Gear Tooth Strengths." International Journal of Innovative Research in Computer Science & Technology 10, no. 4 (July 26, 2022): 218–21. http://dx.doi.org/10.55524/ijircst.2022.10.4.27.

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The idea of using asymmetric tooth forms has gained momentum in gearing design. Similar to symmetric basic rack gears, tooth action parameters are established in the first stage. The second stage involves calculating the unified generating basic rack for a set of mated gears. In some cases, it is possible to determine the features of specific fundamental rack tooth profiles for each gear in a transmission. Gearings with asymmetrical profiles have the advantage of having a higher-pressure angle than operational profiles (as a result of a lower pressure angle than non-operating profiles) and the possibility for a considerable improvement in the face contact ratio. In this study, symmetric and asymmetric tooth profiles will be compared using the finite element analysis tool Ansys. Asymmetric (different pressure angle) and symmetric (different pressure angle) tooth profiles will be designed and built in the 3D modelling software CATIA. The designs made with different materials will go through structural examination (mild steel and EN 32 steel).

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9

Fuhrmeister, B., S. Czesla, J. H. M. M. Schmitt, S. V. Jeffers, J. A. Caballero, M. Zechmeister, A. Reiners, et al. "The CARMENES search for exoplanets around M dwarfs." Astronomy & Astrophysics 615 (July 2018): A14. http://dx.doi.org/10.1051/0004-6361/201732204.

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Stellar activity is ubiquitously encountered in M dwarfs and often characterised by the Hα line. In the most active M dwarfs, Hα is found in emission, sometimes with a complex line profile. Previous studies have reported extended wings and asymmetries in the Hα line during flares. We used a total of 473 high-resolution spectra of 28 active M dwarfs obtained by the CARMENES (Calar Alto high-Resolution search for M dwarfs with Exo-Earths with Near-infrared and optical Echelle Spectrographs) spectrograph to study the occurrence of broadened and asymmetric Hα line profiles and their association with flares, and examine possible physical explanations. We detected a total of 41 flares and 67 broad, potentially asymmetric, wings in Hα. The broadened Hα lines display a variety of profiles with symmetric cases and both red and blue asymmetries. Although some of these line profiles are found during flares, the majority are at least not obviously associated with flaring. We propose a mechanism similar to coronal rain or chromospheric downward condensations as a cause for the observed red asymmetries; the symmetric cases may also be caused by Stark broadening. We suggest that blue asymmetries are associated with rising material, and our results are consistent with a prevalence of blue asymmetries during the flare onset. Besides the Hα asymmetries, we find some cases of additional line asymmetries in He I D3, Na I D lines, and the He I line at 10 830 Å taken all simultaneously thanks to the large wavelength coverage of CARMENES. Our study shows that asymmetric Hα lines are a rather common phenomenon in M dwarfs and need to be studied in more detail to obtain a better understanding of the atmospheric dynamics in these objects.

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10

Almeida, J. Sánchez, and B. W. Lites. "Asymmetric Stokes Q, U and V Line Profiles Observed in Sunspots." International Astronomical Union Colloquium 141 (1993): 177–79. http://dx.doi.org/10.1017/s0252921100029031.

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AbstractWe present a systematic description of the asymmetric shapes the Stokes line profiles exhibit in sunspots. These asymmetries seem to be caused by gradients of both magnetic field and velocity in the photospheres of sunspots.

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11

Bostan, Viorel, Marin Guţu, and Valeriu Odainâi. "Aerodynamic efficiency enhancement for asymmetric profiles." MATEC Web of Conferences 178 (2018): 06022. http://dx.doi.org/10.1051/matecconf/201817806022.

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This paper presents a solution for enhancement of aerodynamic efficiency for asymmetric airfoils. In order to increase the lift and reduce the drag forces for a blade segment, a groove was created on its surface. There were carried out experiments consisting in the analysis of two asymmetric airfoil segments of the same type in the wind tunnel. One segment was designed with the groove and the other without it. The optimum location of the groove was determined by means of CFD analysis. Simulation results were compared to test results and the CFD analysis model was validated.

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12

Zhu, Zhangqin, Jia Zhu, Hanqin Qin, Chong Wang, and Zhongfu Ye. "Exponential Polynomial Fitting for Fibre Spectrum CCD Profiles." Publications of the Astronomical Society of Australia 27, no. 3 (2010): 290–95. http://dx.doi.org/10.1071/as09075.

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AbstractA fibre spectrum profile fitting method based on the least-squares method is presented in this article. For each spectrum of one fibre in spatial orientation, two exponential functions are employed to approximate the profile. Experiments are performed with both simulated profiles and observed profiles to demonstrate the effectiveness of the algorithm. Specially, the proposed method has a better performance for profiles that are asymmetric or composed of multi-Gaussian functions.

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13

Leung, P. T., and Thomas F. George. "Surface distortions of asymmetric line profiles." Chemical Physics Letters 134, no. 4 (March 1987): 375–78. http://dx.doi.org/10.1016/0009-2614(87)87156-7.

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14

Ivanov, Lyuben D. "On Introducing” Section Modulus for Asymmetric Bending” of Stiffeners." Marine Technology and SNAME News 45, no. 01 (January 1, 2008): 9–20. http://dx.doi.org/10.5957/mt1.2008.45.1.9.

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ABSTRACT A new geometric property of shipbuilding structural profiles is introduced to consider asymmetric bending. This is the so-called section modulus for asymmetric bending, which allows for determining the total bending stresses in the structural profile for any angle of the attached plate and any angle of the plane of the applied load. As for symmetric bending, the major assumption behind the developed procedure for calculating the section modulus for asymmetric bending is that the structural profile works as a unit, that is, independently.

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15

Marlin, S., R. Douglas, and M. Cynader. "Position-specific adaptation in complex cell receptive fields of the cat striate cortex." Journal of Neurophysiology 69, no. 6 (June 1, 1993): 2209–21. http://dx.doi.org/10.1152/jn.1993.69.6.2209.

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1. Responses of complex cells in cat striate cortex were studied with flashed light slit stimuli. The responses to slits flashed in different positions in the receptive field were assessed quantitatively before and after periods of prolonged stimulation of one small region of the receptive field. This type of prolonged stimulation resulted in reduced responsivity over a limited zone within the complex cell receptive field. 2. The adaptation-induced responsivity decrement was generally observed in both the ON and OFF response profiles but could also be restricted to one or the other. In general, the magnitude of the response decrements was greatest in the ON response profiles. The adaptation-induced response decrement did not necessarily spread throughout the receptive field but was restricted to a small region surrounding the adapted receptive field position (RFP). Adaptation spread equally widely across the ON and OFF response profiles despite the smaller adaptation effects in the OFF profile. 3. The adaptation effects from repeated stimulation at a single RFP did not spread symmetrically across the receptive field, and a given cell's preferred direction of motion indicated the direction of the asymmetric spread of the adaptation. RFPs that would be stimulated by a light slit originating at the point of adaptation and moving in the preferred direction (preferred side) showed greater adaptation-induced response decrements than did RFPs that would be stimulated by a light slit moving in the opposite direction from the point of adaptation (nonpreferred side). There was significant enhancement of responses at some RFPs on the non-preferred side of the point of adaptation. This asymmetric spread of adaptation could be caused by adaptation of inhibitory connections that contribute to complex cell direction selectivity. 4. The asymmetry of adaptation was significantly different for the ON and OFF response profiles. The asymmetric spread of adaptation for the ON response profile was similar to that observed previously in simple cells with greater decrements in the preferred direction side of the point of adaptation. However, the OFF response profiles showed less directional asymmetry in the spread of adaptation and showed greater decrements at RFPs in the nonpreferred direction side of the point of adaptation. 5. The similarity between the spread of adaptation in simple and complex cells suggests that the adaptation in these cells is occurring through a common mechanism. The directional asymmetry of the spread of adaptation is likely due to a local postsynaptic mechanism of adaptation rather than presynaptic transmitter depletion.

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16

Levine, Lyle E., Peter Geantil, Bennett C. Larson, Jonathan Z. Tischler, Michael E. Kassner, and Wenjun Liu. "Validating classical line profile analyses using microbeam diffraction from individual dislocation cell walls and cell interiors." Journal of Applied Crystallography 45, no. 2 (March 15, 2012): 157–65. http://dx.doi.org/10.1107/s0021889812001616.

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Dislocation structures in deformed metals produce broad asymmetric diffraction line profiles. During analysis, these profiles are generally separated into two nearly symmetric subprofiles corresponding to diffraction by dislocation cell walls and cell interiors. These subprofiles are then interpreted using complex models of dislocation-based line broadening. Until now, it has not been possible to test the many assumptions that are made in such an analysis. Here, depth-resolved microbeam diffraction was used to measure diffraction line profiles from numerous individual dislocation cell walls and cell interiors in a heavily deformed Cu single crystal. Summing these profiles directly constructed the cell-interior and cell-wall subprofiles that have been approximated in the line profile analysis literature for the past 30 years. Direct comparison between the reconstructed subprofiles and the macroscopic asymmetric line profile from the same sample allows the first direct tests of many of the assumptions that have been used for interpreting these X-ray measurements.

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17

Abdullah, Mohammad Qasim, and Mohammed Abdulaal Kadum. "Stress Concentration factor Analysis of Helical Gear Drives with Asymmetric Teeth Profiles." Journal of Engineering 24, no. 5 (May 1, 2018): 14. http://dx.doi.org/10.31026/j.eng.2018.05.02.

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This study investigates the influence of asymmetric involute teeth profiles for helical gears on the bending stress. Theoretically, bending stress has been estimated in spur involute gears which have symmetric teeth profile by based on the Lewis, 1892 equation. Later, this equation is developed by, Abdullah, 2012. to determine the effect of an asymmetric tooth profile for the spur gear on the bending stress. And then these equations are applied with stress concentration factor once for symmetric and once other for asymmetric teeth profile. In this paper, the bending stresses for various types of helical gear with various types of asymmetric teeth profile are calculated numerically for defined the stress concentration factor. The numerical solution based on the finite element method technique which that done by using the software simulation SolidWorks 2016. The results of this study indicate that the helical gear drive with asymmetric teeth profile having 'loaded side pressure angle' of ( ) and 'unloaded side pressure angle' of ( ) is better than a helical gear with standard teeth profile having pressure angle of ( ) from the regarding of tooth bending strength. Also, notes that the great enhancement in the results of maximum tooth bending stress for modified involute of tooth profile compared with the standard teeth profile. In addition to, predict the equation of stress concentration factor which is a function of both unloaded side pressure angle and helix angle and then it used with Abdullah equation for to determine the nominal stresses in the root fillet.

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18

Tang, C. C., P. A. Lynch, R. W. Cheary, and S. M. Clark. "Anin situmethod for the study of strain broadening using synchrotron X-ray diffraction." Journal of Applied Crystallography 40, no. 4 (July 13, 2007): 642–49. http://dx.doi.org/10.1107/s0021889807016299.

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A tensonometer for stretching metal foils has been constructed for the study of strain broadening in X-ray diffraction line profiles. This device, which is designed for use on powder diffractometers and was tested on Station 2.3 at Daresbury Laboratory, allowsin situmeasurements to be performed on samples under stress. It can be used for data collection in either transmission or reflection modes using either symmetric or asymmetric diffraction geometries. As a test case, measurements were carried out on an 18 µm-thick copper foil experiencing strain levels of up to 5% using both symmetric reflection and symmetric transmission diffraction. All the diffraction profiles displayed peak broadening and asymmetry which increased with strain. The measured profiles were analysed by the fundamental-parameters approach using theTOPASpeak-fitting software. All the observed broadened profiles were modelled by convoluting a refineable diffraction profile, representing the dislocation and crystallite size broadening, with a fixed instrumental profile predetermined using high-quality LaB6reference powder. The deconvolution process yielded `pure' sample integral breadths and asymmetry results which displayed a strong dependence on applied strain and increased almost linearly with applied strain. Assuming crystallite size broadening in combination with dislocation broadening arising from f.c.c.a/2〈110〉{111} dislocations, the variation of mechanical property with strain has been extracted. The observation of both peak asymmetry and broadening has been interpreted as a manifestation of a cellular structure with cell walls and cell interiors possessing high and low dislocation densities.

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19

Cvetanov, Genadi, and Tsanko Karadzhov. "GEOMETRIC SYNTHESIS OF INVOLUTE PLANETARY GEARS WITH CONNECTED GEAR WHEELS OF TYPE 2K-H." ENVIRONMENT. TECHNOLOGIES. RESOURCES. Proceedings of the International Scientific and Practical Conference 3 (June 16, 2021): 49–53. http://dx.doi.org/10.17770/etr2021vol3.6643.

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Based on the basic law of flat interlocking, the paper considers a possibility of increasing the gear ratio of low module involute cylindrical planetary gears by using asymmetric tooth profile for the purposes of measuring devices. An example of the synthesis of such reduction gearing by optimal choice of asymmetry between the profiles and Possibility of generation III is presented. Also presented is a planar matching of the unconditional existence areas in the field of independent coefficients of instrument displacement by the straight optimization method and pre-set qualitative indicators of the gearing.

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20

De Martin, Andrea, Giovanni Jacazio, and Massimo Sorli. "Optimization of Gerotor Pumps with Asymmetric Profiles through an Evolutionary Strategy Algorithm." Machines 7, no. 1 (March 1, 2019): 17. http://dx.doi.org/10.3390/machines7010017.

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Gerotor pumps are widely used for fuel and lubricating oil distribution, since they provide an economic and compact solution for low-pressure fluid systems. Made of two internally coupled gears, their behavioral and operative performances are strictly tied to their geometrical designs. Traditionally, the external gear features circular lobes that give origin to a cycloidal profile for the internal rotor. In this paper, the use of profiles based on asymmetric lobes made of elliptic arcs is further explored and expanded. At first, a complete mathematical framework describing the pump geometry and its dynamic behavior is provided, while algorithms used to compute a selected number of performance indexes are presented and when possible, verified. Hence, a single-objective optimization procedure is applied to the traditional cycloidal profile, in order to minimize each of the following quantities: the flow rate irregularity, the expected wear rate, and the estimated rotor mass. Finally, a multi-objective optimization process based on evolutionary strategy is employed, to obtain several asymmetric profiles minimizing the combination of two or more performance indexes. The results are hence compared, and the merits associated with the use of asymmetric lobes are presented.

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21

Yang, Yang, Zhibo Jiang, Zhiwei Chen, Yiping Ao, and Shuling Yu. "In Search of Infall Motion in Molecular Clumps. III. HCO+ (1-0) and H13CO+ (1-0) Mapping Observations toward Confirmed Infall Sources." Astrophysical Journal 922, no. 2 (November 26, 2021): 144. http://dx.doi.org/10.3847/1538-4357/ac22ab.

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Abstract The study of infall motion helps us to understand the initial stages of star formation. In this paper, we use the IRAM 30 m telescope to make mapping observations of 24 infall sources confirmed in previous work. The lines we use to track gas infall motions are HCO+ (1-0) and H13CO+ (1-0). All 24 sources show HCO+ emissions, while 18 sources show H13CO+ emissions. The HCO+ integrated intensity maps of 17 sources show clear clumpy structures; for the H13CO+ line, 15 sources show clumpy structures. We estimated the column density of HCO+ and H13CO+ using the RADEX radiation transfer code, and the obtained [HCO+]/[H2] and [H13CO+]/[HCO+] of these sources are about 10−11–10−7 and 10−3–1, respectively. Based on the asymmetry of the line profile of the HCO+, we distinguish these sources: 19 sources show blue asymmetric profiles, and the other sources show red profiles or symmetric peak profiles. For eight sources that have double-peaked blue line profiles and signal-to-noise ratios greater than 10, the RATRAN model is used to fit their HCO+ (1-0) lines, and to estimate their infall parameters. The mean V in of these sources is 0.3–1.3 km s−1, and the M ̇ in is about 10−3–10−4 M ⊙ yr−1, which is consistent with the results of intermediate or massive star formation in previous studies. The V in estimated from the Myers model is 0.1–1.6 km s−1, and the M ̇ in is within 10−3–10−5 M ⊙ yr−1. In addition, some identified infall sources show other star-forming activities, such as outflows and maser emissions. Especially for those sources with a double-peaked blue asymmetric profile, most of them have both infall and outflow evidence.

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Boryga, Marek, Paweł Kołodziej, and Krzysztof Gołacki. "The Use of Asymmetric Polynomial Profiles for Planning a Smooth Trajectory." Applied Sciences 12, no. 23 (November 30, 2022): 12284. http://dx.doi.org/10.3390/app122312284.

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This paper presents planning of smooth trajectories using the asymmetric profiles of displacement, velocity, acceleration and jerk of described higher degree polynomials. The presented way of determination of polynomial and asymmetry coefficients as well as motion time includes the procedure at both constraints of single kinematic quantities, i.e., velocity, acceleration, jerk and introducing a few constraints simultaneously. Moreover, the paper presents a method of planning trajectories with intermediate points consisting in concatenation of the analyzed polynomials. The proposed method of trajectory planning was compared to that of using the S-curve. The results in the form of kinematic quantity courses are presented graphically. The discussed method guarantees continuity of displacement, velocity, acceleration and jerk. It can be used for planning trajectories of various technical objects (e.g., manipulators, mobile robots, CNC machine tools, optical disk drives, autonomous vehicles, etc.).

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23

Coyle, R. A. "Numerical Calculation of Axial Divergence Profiles." Advances in X-ray Analysis 35, A (1991): 611–16. http://dx.doi.org/10.1154/s0376030800009320.

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AbstractThe diffractometer instrumental profiles convoluted by Alexander from aberration profiles calculated using the methods developed Easterbrook, Pike and Wilson include two profiles which are not amenable to exact analytical solution. These two profiles are generated by the axial divergence and flat specimen aberrations. Using ray tracing techniques the exact profiles of these two aberrations have been computed for the Philips PW1050 and Scintag DA5 diffractometers. sample profiles at 2θ = 28°, 90° and 152° have been convoluted with the third asymmetric profile, that due to specimen transparency, and plots of the resultant profiles are shown. Shifts of the centroids and the peaks of the profiles from the true Bragg angle have also been computed and plotted over the range 2θ = 0°-180°.

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24

Ungár, T., I. Groma, and M. Wilkens. "Asymmetric X-ray line broadening of plastically deformed crystals. II. Evaluation procedure and application to [001]-Cu crystals." Journal of Applied Crystallography 22, no. 1 (February 1, 1989): 26–34. http://dx.doi.org/10.1107/s0021889888009720.

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In paper I [Groma, Ungár & Wilkens (1988). J. Appl. Cryst. 21, 47–53] a theory was developed to interpret the asymmetric X-ray line broadening of plastically deformed crystals. It was shown that the dislocation structure can be described by five distinct parameters, namely the dislocation density, the mean quadratic spatial fluctuation of the dislocation density, the effective outer cut-off radius, the dipole polarization and the spatial fluctuation of the dipole polarization of the dislocation structure. In this paper a procedure is developed to evaluate these parameters from the Fourier transform of the line profiles. The theory and this procedure are tested by applying it to the asymmetric line profiles of tensile-deformed Cu single crystals orientated for ideal multiple slip. The asymmetry of these profiles is assigned to the dipole polarization of the dislocation cell structure and is directly correlated to residual long-range internal stresses. It is shown that the data can be interpreted in terms of the quasi-composite model of the dislocation cell structure developed earlier for the same material.

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Groma, I., and G. Monnet. "Analysis of asymmetric broadening of X-ray diffraction peak profiles caused by randomly distributed polarized dislocation dipoles and dislocation walls." Journal of Applied Crystallography 35, no. 5 (September 18, 2002): 589–93. http://dx.doi.org/10.1107/s0021889802010695.

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The problem of asymmetric X-ray diffraction peak broadening caused by dislocations is investigated. The leading term responsible for the asymmetry of the intensity distribution is calculated for randomly distributed polarized dipoles and dipole walls. It is found that the polarization structure of a dislocation ensemble can be determined from the diffraction order dependence of the profile asymmetry.

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Yardley, S. L., D. H. Brooks, and D. Baker. "Widespread occurrence of high-velocity upflows in solar active regions." Astronomy & Astrophysics 650 (June 2021): L10. http://dx.doi.org/10.1051/0004-6361/202141131.

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Aims. We performed a systematic study of 12 active regions (ARs) with a broad range of areas, magnetic fluxes, and associated solar activity in order to determine whether there are upflows present at the AR boundaries and, if these upflows exist, whether there is a high-speed asymmetric blue wing component present in them. Methods. To identify the presence and locations of the AR upflows, we derive relative Doppler velocity maps by fitting a Gaussian function to Hinode/EIS Fe XII 192.394 Å line profiles. To determine whether there is a high-speed asymmetric component present in the AR upflows, we fit a double Gaussian function to the Fe XII 192.394 Å mean spectrum that is computed in a region of interest situated in the AR upflows. Results. Upflows are observed at both the eastern and western boundaries of all ARs in our sample, with average upflow velocities ranging between −5 and −26 km s−1. A blue wing asymmetry is present in every line profile. The intensity ratio between the minor high-speed asymmetric Gaussian component compared to the main component is relatively small for the majority of regions; however, in a minority of cases (8/30) the ratios are large and range between 20 and 56 %. Conclusions. These results suggest that upflows and the high-speed asymmetric blue wing component are a common feature of all ARs.

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Negishi, Nobuyuki, Masatoshi Miyake, Keigo Takeda, and Masaru Hori. "Mechanism of asymmetric etched profiles in trimming process." Japanese Journal of Applied Physics 57, no. 10 (September 3, 2018): 106201. http://dx.doi.org/10.7567/jjap.57.106201.

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Kargin, P. A. "Prospects for involute transmissions with asymmetric tooth profiles." Russian Engineering Research 35, no. 1 (January 2015): 3–7. http://dx.doi.org/10.3103/s1068798x15010128.

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Narang, Aradhana, and A. J. Shaiju. "Evolutionary Stability of Polymorphic Profiles in Asymmetric Games." Dynamic Games and Applications 9, no. 4 (February 13, 2019): 1126–42. http://dx.doi.org/10.1007/s13235-019-00302-6.

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Sorge, S., and S. Günter. "Simulation of shifted and asymmetric hydrogen line profiles." European Physical Journal D 12, no. 2 (October 2000): 369–75. http://dx.doi.org/10.1007/s100530070033.

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Zhu, X., P. Predecki, M. Eatough, and R. Goebner. "Residual Stress Depth Profiling on Ground and on Polished Surfaces of an Al2O3/SiC(w) Composite." Advances in X-ray Analysis 39 (1995): 371–80. http://dx.doi.org/10.1154/s0376030800022783.

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This study uses the asymmetric grazing incidence x-ray diffraction (GIXD) method and related z-profile retrieval techniques to study the near surface residual stress depth proflles on ground and on polished surfaces of hot-pressed Al2O2SiC(w) composite specimen. The z-profiles of stress components σ11, σ22 and σ33 of the Al2O3 matrix were obtained by using the numerical inversion method as well as the inverse Laplace method. Both τ- and z-profiles of residual stresses are presented.

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Menezes, Lidiane Teles de, Paulo Henrique Ferreira de Araujo Barbosa, Abraão Souza Costa, Anderson Castro Mundim, Gabrielly Craveiro Ramos, Clarissa Cardoso dos Santos Couto Paz, and Emerson Fachin Martins. "Baropodometric technology used to analyze types of weight-bearing during hemiparetic upright position." Fisioterapia em Movimento 25, no. 3 (September 2012): 583–94. http://dx.doi.org/10.1590/s0103-51502012000300014.

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INTRODUCTION: Although baropodometric analysis has been published since the 1990s, only now it is found a considerable number of studies showing different uses in the rehabilitation. OBJECTIVE: To amplify the use of this technology, this research aimed to analyze baropodometric records during upright position of subjects with hemiparesis, describing a way to define weight-bearing profiles in this population. METHOD: 20 healthy subjects were matched by gender and age with 12 subjects with chronic spastic hemiparesis. This control group was formed to establish the limits of symmetry during weight-bearing distribution in the hemiparesis group. Next, hemiparesis group was submitted to procedures to measure baropodometric records used to provide variables related to the weight-bearing distribution, the arch index and the displacements in the center of pressure (CoP). Data were used to compare differences among kinds of weight-bearing distribution (symmetric, asymmetric toward non-paretic or paretic foot) and coordination system for CoP displacements. RESULTS: Hemiparesis group was compounded by eight symmetrics, eight asymmetrics toward non-paretic foot and four asymmetric toward paretic foot. Significant differences in the weight-bearing distributions between non-predominantly and predominantly used foot did not promote differences in the other baropodometric records (peak and mean of pressure, and support area). Mainly in the asymmetry toward non-paretic foot it was observed significant modifications of the baropodometric records. CONCLUSION: Baropodometric technology can be used to analyze weight-bearing distribution during upright position of subjects with hemiparesis, detecting different kinds of weight-bearing profiles useful to therapeutic programs and researches involving subjects with this disability.

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Cordero, Patricio, Dino Risso, and Rodrigo Soto. "Effect of the vibration profile on shallow granular systems." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 373, no. 2056 (December 13, 2015): 20150116. http://dx.doi.org/10.1098/rsta.2015.0116.

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We describe the collective behaviour of a system of many inelastic spherical particles inside a box which is being periodically vibrated. The box is shallow, with large horizontal dimensions, while the height is less than two particle diameters. The vibrations are not symmetric: the time the box is moving up is, in general, different from the time it is moving down. The limit cycles of isolated grains are largely affected by the asymmetry of the vibration mode, increasing the size in phase space of the chaotic regions. When many grains are placed in the box, the phase separation between dense, solid-like regions, coexisting with fluid-like regions takes place at smaller global densities for asymmetric vibration profiles. Besides, the order parameter of the transition takes larger values when asymmetric forcing is used.

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Ida, T., and K. Kimura. "Effect of sample transparency in powder diffractometry with Bragg–Brentano geometry as a convolution." Journal of Applied Crystallography 32, no. 5 (October 1, 1999): 982–91. http://dx.doi.org/10.1107/s0021889899008894.

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The effect of transparency and finite thickness of the sample on the peak profile in powder diffractometry with Bragg–Brentano geometry is treated as a convolution with an asymmetric aberration function. The formula of the aberration function and a practical method for numerical calculation of the convolution are proposed. The model function for the total profile is given by triple convolution of the pseudo-Voigt function with asymmetric functions based on vertical (axial) divergence, horizontal (equatorial) divergence and sample transparency. The validity of the model profile function is examined by fitting the CuKα X-ray diffraction profile of diluted lanthanum hexaboride (LaB6) standard samples (SRM660) of 0.5 mm thickness, the transparency of which is varied by mixing with different amounts of starch; all the parameters that may affect the shape of the profile function are treated as fixed parameters. Even in the case of heavily distorted profiles of highly transparent samples with the inverse linear absorption coefficients μ−1= 0.34 and 1.19 mm, experimental profiles are fairly well reproduced by the model function, typically within several % inRfactor. It is also demonstrated that the lattice constants of the transparent samples are precisely evaluated by applying this model function.

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Vergados, J. D. "Asymmetric Velocity Distributions from Halo Density Profiles in the Eddington Approach." Advances in High Energy Physics 2015 (2015): 1–11. http://dx.doi.org/10.1155/2015/374061.

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We show how to obtain the energy distributionf(E)in our vicinity starting from WIMP density profiles in a self-consistent way by employing the Eddington approach and adding reasonable angular momentum dependent terms in the expression of the energy. We then show how we can obtain the velocity dispersions and the asymmetry parameterβin terms of the parameters describing the angular momentum dependence. From this expression, forf(E), we proceed to construct an axially symmetric WIMP a velocity distribution, which, for a gravitationally bound system, automatically has a velocity upper bound and is characterized by the same asymmetriyβ. This approach is tested and clarified by constructing analytic expressions in a simple model, with adequate structure. We then show how such velocity distributions can be used in determining the event rates, including modulation, in both the standard and the directional WIMP searches.

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Narang, Aradhana, and A. J. Shaiju. "Globally Strong Uninvadable Sets of Profiles in Asymmetric Games." International Game Theory Review 22, no. 01 (December 6, 2019): 1950014. http://dx.doi.org/10.1142/s0219198919500142.

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The concept of a globally strong uninvadable set of profiles is studied for asymmetric evolutionary games. After establishing a general result concerning weak [Formula: see text]-limit points of the replicator dynamics trajectories, we prove that globally strong uninvadable sets are weak attracting.

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37

Deng, Xiaohe, Lin Hua, and Xinghui Han. "Research on the Design and Modification of Asymmetric Spur Gear." Mathematical Problems in Engineering 2015 (2015): 1–13. http://dx.doi.org/10.1155/2015/897257.

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A design method for the geometric shape and modification of asymmetric spur gear was proposed, in which the geometric shape and modification of the gear can be obtained directly according to the rack-cutter profile. In the geometric design process of the gear, a rack-cutter with different pressure angles and fillet radius in the driving side and coast side was selected, and the generated asymmetric spur gear profiles also had different pressure angles and fillets accordingly. In the modification design of the gear, the pressure angle modification of rack-cutter was conducted firstly and then the corresponding modified involute gear profile was obtained. The geometric model of spur gears was developed using computer-aided design, and the meshing process was analyzed using finite element simulation method. Furthermore, the transmission error and load sharing ratio of unmodified and modified asymmetric spur gears were investigated. Research results showed that the proposed gear design method was feasible and desired spur gear can be obtained through one time rapid machining by the method. Asymmetric spur gear with better transmission characteristic can be obtained via involute modification.

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Pesin, Alexander, Mikhail Chukin, Alexey Korchunov, and D. O. Pustovoytov. "Finite Element Modeling of Shear Strain in Rolling with Velocity Asymmetry in Multi-Roll Calibers." Key Engineering Materials 622-623 (September 2014): 912–18. http://dx.doi.org/10.4028/www.scientific.net/kem.622-623.912.

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Severe plastic deformation is now recognized the most efficient way of producing ultrafine grained metals and alloys. At the present time a lot of severe plastic deformation methods have been proposed and developed. They differ in the deformation schemes. Unlike such severe plastic deformation methods as high pressure torsion and equal-channel angular pressing, rolling with the velocity asymmetry is a continuous process. It helps to solve the problem of the limited length of manufactured bars with semi ultrafine structure. Rolling process with roll velocity asymmetry generates high shear strain necessary for obtaining ultrafine structures of the processed material. A new process of asymmetric rolling of profiles in multi-roll passes has been developed. This process can be used for production of high-strength profiles such as circles, hexagons, wire rods, etc. Compression of the bar in multi-roll passes can be done not only from two, as usual, but from three or four sides. In case of a multi-crimped bar, a uniform compression scheme with large hydrostatic pressure is created in the deformation zone. It enhances the ductility of the material and allows increasing the strain intensity. Simulation in DEFORM 3DTM proved that the process of asymmetric rolling in multi-roll calibers allows to obtain higher values of shear strain and strain effective.

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39

Naito, Ryo, and Tomohiro Fukui. "Numerical Study of the Effects of Asymmetric Velocity Profiles in a Curvilinear Channel on Migration of Neutral Buoyant Particle." Fluids 8, no. 2 (February 16, 2023): 69. http://dx.doi.org/10.3390/fluids8020069.

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The microstructure and suspended particle behavior should be considered when studying the flow properties exhibited by particle suspension. In addition, particle migration, also known as Segré–Silberberg effects, alters the microstructure of the suspension and significantly affects the viscosity properties of the suspension. Therefore, particle behavior with respect to the changes in mechanical factors should be considered to better understand suspension. In this study, we investigated the particle behavior in asymmetric velocity profiles with respect to the channel center numerically using the lattice Boltzmann method and a two-way coupling scheme. Our findings confirmed that the final equilibrium position of particles in asymmetric velocity profiles converged differently between the outer and inner wall sides with respect to the channel center. This indicates that the mechanical equilibrium position of particles can be changed by asymmetric velocity profiles. In addition, centrifugal force acting on the particles is also important in the study of equilibrium position. These results suggest that the microstructure and viscosity characteristics of a suspension in a pipe could be handled by changes in velocity profiles.

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Cao, Renshui, Hang Bai, Hui Cao, Yazhao Zhang, and Yonggang Meng. "Mixed Lubrication Analysis of Tapered Roller Bearings and Crowning Profile Optimization Based on Numerical Running-In Method." Lubricants 11, no. 3 (February 24, 2023): 97. http://dx.doi.org/10.3390/lubricants11030097.

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Tapered roller bearings (TRBs) are widely used in heavy-load rotating machinery. One of the technical problems in TRBs is the existence of sharp spikes of the contact pressure in the vicinity of the two ends of the tapered rollers. To suppress the pressure spikes at the roller ends, a straight roller profile is crowned in cylindrical and tapered roller bearings. However, compared to cylindrical roller bearings, there are few studies on the profile modification of TRBs in the literature, and most of the publications on the EHD analysis of tapered rollers focused on a single roller, using traditional profiles such as logarithmic profiles, dub-off profiles and chamfer profiles. By using the numerical running-in method proposed and used in crowning profiles of cylindrical rollers by the authors, this paper provides the first ever asymmetric optimized profile solution for all TRBs rather than for just a single roller. The results show that the optimized profile has the best performance in smoothing contact pressure distribution in the axial direction compared with the conventional logarithmic profile and is a useful profile form with respect to the elimination of sharp pressure spikes. In addition, considering the effect of temperature and mixed lubrication, this paper analyzes the influences of different axial profiles under radial load (Fr), rotation speed (N) and standard deviation of roughness (Rq) conditions.

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lemmi, C. C., Juan M. Simon, and J. O. Ratto. "Synthesis of asymmetric profiles from a double grating interferometer." Applied Optics 25, no. 18 (September 15, 1986): 3171. http://dx.doi.org/10.1364/ao.25.003171.

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42

Zhang, Jun, Stephen Childress, and Albert Libchaber. "Non-Boussinesq effect: Asymmetric velocity profiles in thermal convection." Physics of Fluids 10, no. 6 (June 1998): 1534–36. http://dx.doi.org/10.1063/1.869672.

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Ida, Takashi. "An efficient method for calculating asymmetric diffraction peak profiles." Review of Scientific Instruments 69, no. 11 (November 1998): 3837–39. http://dx.doi.org/10.1063/1.1149220.

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44

Schivell, J., and C. E. Bush. "Analysis of highly asymmetric radiation loss profiles in TFTR." Review of Scientific Instruments 57, no. 8 (August 1986): 2081–83. http://dx.doi.org/10.1063/1.1138745.

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45

Gabriel, A. H., J. P. Connerade, S. Thiery, and P. Boumier. "Application of Fano profiles to asymmetric resonances in helioseismology." Astronomy & Astrophysics 380, no. 2 (December 2001): 745–49. http://dx.doi.org/10.1051/0004-6361:20011450.

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46

Regan, B. C., Brian Zutter, William A. Hubbard, Shaul Aloni, and Matthew Mecklenburg. "Asymmetric Temperature Profiles in Joule-Heated in Aluminum Nanowires." Microscopy and Microanalysis 22, S3 (July 2016): 772–73. http://dx.doi.org/10.1017/s1431927616004712.

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47

Mohr, Erich, Ulrike M. Mann, Robert S. Miletich, Margaret Sampson, Terry E. Goldberg, J. David Crimes, and Thomas N. Chase. "Neuropsychological and Glucose Metabolic Profiles in Asymmetric Parkinson’s Disease." Canadian Journal of Neurological Sciences / Journal Canadien des Sciences Neurologiques 19, no. 2 (May 1992): 163–69. http://dx.doi.org/10.1017/s0317167100042207.

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ABSTRACT:Patients with predominantly unilateral parkinsonian signs may provide a unique opportunity to evaluate the cerebral representation of cognitive functions characteristically affected in idiopathic Parkinson’s disease. Twenty hemiparkinsonian patients (ten left and ten right) and 10 healthy controls, matched for age and education, were studied with neuropsychological tests and positron emission tomography. Both right and left hemiparkinsonians evidenced impairments in visuospatial and verbal episodic memory function, but had no deficits in executive abilities, compared to controls. None of the neuropsychological test scores distinguished right from left hemiparkinsonians. Glucose metabolic profiles were identical for the three groups in all cortical areas assessed; in the subcortex however, lenticular hypermetabolism contralateral to the predominant side of motor involvement was evident in the left hemiparkinsonian group. Correlational analysis revealed that higher glucose metabolic rates in the basal ganglia of these hemiparkinsonians were associated with lower visuospatial test scores. In frontal and parietal cortex, decreasing glucose metabolism was positively associated with neurobehavioral function; in temporal cortex, measures of attention and memory decreased with increasing glucose metabolic rates.

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Kargin, P. A. "Transition curve of involute gear teeth with asymmetric profiles." Russian Engineering Research 31, no. 3 (March 2011): 200–202. http://dx.doi.org/10.3103/s1068798x11030129.

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49

Toraya, H., and J. Yoshino. "Profiles in asymmetric diffraction with pseudo-parallel-beam geometry." Journal of Applied Crystallography 27, no. 6 (December 1, 1994): 961–66. http://dx.doi.org/10.1107/s0021889894006345.

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50

Duanmu, M., K. Li, R. L. Horne, P. G. Kevrekidis, and N. Whitaker. "Linear and nonlinear parity-time-symmetric oligomers: a dynamical systems analysis." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 371, no. 1989 (April 28, 2013): 20120171. http://dx.doi.org/10.1098/rsta.2012.0171.

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In the present work, we focus on the cases of two-site (dimer) and three-site (trimer) configurations, i.e. oligomers, respecting the parity-time ( ) symmetry, i.e. with a spatially odd gain–loss profile. We examine different types of solutions of such configurations with linear and nonlinear gain/loss profiles. Solutions beyond the linear -symmetry critical point as well as solutions with asymmetric linearization eigenvalues are found in both the nonlinear dimer and trimer. The latter feature is absent in linear -symmetric trimers, while both of them are absent in linear -symmetric dimers. Furthermore, nonlinear gain/loss terms enable the existence of both symmetric and asymmetric solution profiles (and of bifurcations between them), while only symmetric solutions are present in the linear -symmetric dimers and trimers. The linear stability analysis around the obtained solutions is discussed and their dynamical evolution is explored by means of direct numerical simulations. Finally, a brief discussion is also given of recent progress in the context of -symmetric quadrimers.

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