Статті в журналах: "Angle of coincidence"

1

Wehlitz, R., L. S. Pibida, J. C. Levin, and I. A. Sellin. "Angle-resolving electron-electron coincidence setup." Review of Scientific Instruments 70, no. 4 (April 1999): 1978–82. http://dx.doi.org/10.1063/1.1149697.

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2

Ikuhara, Yumi H., Shinji Kondoh, Koichi Kikuta, and Shin-ichi Hirano. "Microstructure characterization of one-directionally oriented ulexite." Journal of Materials Research 13, no. 3 (March 1998): 778–83. http://dx.doi.org/10.1557/jmr.1998.0099.

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Microstructures of ulexite were investigated by CTEM and low electron dose HREM. It was found that the longitudinal grains in ulexite were oriented to c-direction to form a bundle structure. There were a number of small-angle grain boundaries and stacking faults inside a grain in the ulexite. Cleavage microcracks and stacking faults were mostly introduced on the {010} of the ulexite. The high-angle grain boundaries mainly consisted of high coincidence boundaries, which was confirmed by a comparison of observed contact angles and calculated degree of coincidence at the boundaries. The light transmittance properties of the ulexite would depend on the defects such as stacking fault, small-angle grain boundary, and high-angle grain boundary.

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3

Cui, Zhaoliang, Rui He, Wanyu Wu, Fengtao Wang, and Liu Heng. "Effect of structural parameters and service conditions on the tilt angle of double row angular contact ball bearing." Proceedings of the Institution of Mechanical Engineers, Part K: Journal of Multi-body Dynamics 236, no. 1 (December 17, 2021): 168–81. http://dx.doi.org/10.1177/14644193211061002.

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In this paper, for double row angular contact ball bearing, a five-degrees-of-freedom bearing analysis model based on quasi-statics is proposed. This model is used to study the influence of structural parameters and service conditions on the tilt angle and limit tilt angle of the bearing. The results show that the radial clearance will increase the ultimate tilt angle. The coincidence degree between the roller and the inner raceway will reduce the ultimate tilt angle, but the coincidence degree between the roller and the outer raceway has the opposite effect. The increase in the external load of the bearing will increase the tilt angle. The moment load has the greatest effect on the tilt angle. The rotation speed of the bearing has no effect on the tilt angle. The coincidence degree between the roller and the raceway will reduce the tilt angle; furthermore, the influence of the coincidence degree between roller and different ring on the tilt angle is also different when different rings are fixed. The tilt angle will decrease with the increase of the initial contact angle, and this effect is more and more obvious. The fixation of different ring has no effect on this influence.

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4

Sun, Hongyan, and Stephen Pistorius. "Evaluation of the Feasibility and Quantitative Accuracy of a Generalized Scatter 2D PET Reconstruction Method." ISRN Biomedical Imaging 2013 (February 28, 2013): 1–11. http://dx.doi.org/10.1155/2013/943051.

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Scatter degrades the contrast and quantitative accuracy of positron emission tomography (PET) images, and most methods for estimating and correcting scattered coincidences in PET subtract scattered events from the measured data. Compton scattering kinematics can be used to map out the locus of possible scattering locations. These curved lines (2D) or surfaces (3D), which connect the coincidence detectors, encompass the surface (2D) or volume (3D) where the decay occurs. In the limiting case where the scattering angle approaches zero, the scattered coincidence approaches the true coincidence. Therefore, both true and scattered coincidences can be considered similarly in a generalized scatter maximum-likelihood expectation-maximization reconstruction algorithm. The proposed method was tested using list-mode data obtained from a GATE simulation of a Jaszczak-type phantom. For scatter fractions from 10% to 60%, this approach reduces noise and improves the contrast recovery coefficients by 0.5–3.0% compared with reconstructions using true coincidences and by 3.0–24.5% with conventional reconstruction methods. The results demonstrate that this algorithm is capable of producing images entirely from scattered photons, eliminates the need for scatter corrections, increases image contrast, and reduces noise. This could be used to improve diagnostic quality and/or to reduce patient dose and radiopharmaceutical cost.

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5

Chu, Wei-Kan. "Large angle coincidence spectrometry for neutron depth profiling." Radiation Effects and Defects in Solids 108, no. 1 (May 1989): 125–26. http://dx.doi.org/10.1080/10420158908217875.

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6

Havránek, V., V. Hnatowicz, J. Kvítek, J. Vacík, J. Hoffmann, and D. Fink. "Neutron depth profiling by large angle coincidence spectrometry." Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms 73, no. 4 (April 1993): 523–30. http://dx.doi.org/10.1016/0168-583x(93)95836-t.

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7

Golovin, A. V. "Angle-resolved ion–electron coincidence experiments in molecular photoionization." Journal of Electron Spectroscopy and Related Phenomena 96, no. 1-3 (November 1998): 117–26. http://dx.doi.org/10.1016/s0368-2048(98)00227-8.

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8

Bortoletto, Alexandre, and Roberto K. Saito. "Observing mutual events of the trans-Neptunian object Haumea and Namaka from Brazil." Proceedings of the International Astronomical Union 6, S269 (January 2010): 189–92. http://dx.doi.org/10.1017/s1743921310007404.

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AbstractBy pure coincidence, for the next few years the orbit of the satellite Namaka around the dwarf planet Haumea (formerly 2003 EL61) is nearly edge-on to our line-of-sight. This type of configuration does not last for long, because as Haumea travels around the sun in its 283 year orbit, we continuously see the Haumean system from different angles. It is only edge-on at the angle we see right now, and at the angle it will again be in 141 years – half of a Haumean year from now. In addition to being an interesting coincidence, the fact that the orbit of Namaka is nearly edge-on provides the opportunity to obtain an enormous amount of information about the Haumean system. We present measurements of the timing of these events observed from Laboratrio Nacional de Astrofsica (LNA), partner in an international campaign to observe these events from the most suitable mid-sized telescopes.

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9

Zhu, Yimei, H. Zhang, H. Wang та M. Suenaga. "Grain boundary in textured YBa2Cu3O7−δ superconductor". Journal of Materials Research 6, № 12 (грудень 1991): 2507–18. http://dx.doi.org/10.1557/jmr.1991.2507.

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The misorientations of over 200 pairs of adjacent grains separated by grain boundaries in textured YBa2Cu3O7−δ were measured using a transmission electron microscopy technique. The results indicate that there exist discrete preferred rotation angles and rotation axes. The existence of low-energy boundaries is inferred. The results are analyzed based on the Constrained Coincidence Site Lattice (CCSL) and O2-lattice theories and imply the applicability of such theories for the case of large-angle grain boundaries in a complex crystal structure such as YBa2Cu3O7−δ. The results of analysis also show that some boundaries are likely to be reduced in oxygen near the boundary to satisfy the constraint of the coincidence site lattice.

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10

Kirschner, J., O. M. Artamonov, and S. N. Samarin. "Angle Resolved Energy Correlated Coincidence Electron Spectroscopy of Solid Surfaces." Physical Review Letters 75, no. 12 (September 18, 1995): 2424–27. http://dx.doi.org/10.1103/physrevlett.75.2424.

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11

Lefevere, Yke, Jan H. M. Bijleveld, Martin Doets, Norbert Idskes, Thomas S. Bauer, Herbert Breuer, and Mahbubul A. Khandaker. "A liquid helium target for large solid angle coincidence experiments." Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 290, no. 1 (May 1990): 34–40. http://dx.doi.org/10.1016/0168-9002(90)90343-5.

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12

Wang, Kai, Xiangdong Jiao, Jialei Zhu, Changlei Shao, and Congwei Li. "Effect of nitrogen protection on weld metal microstructure and intergranular behavior of S32101 duplex stainless steel 15 m water depth hyperbaric laser underwater welding." Advances in Mechanical Engineering 14, no. 1 (January 2022): 168781402110729. http://dx.doi.org/10.1177/16878140211072943.

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In this study, 16-mm-thick S32101 duplex stainless steel were welded using hyperbaric underwater laser welding system in 0.15 MPa. The misorientation angle distribution of grain boundaries in the weld metal was analyzed using the electron backscatter diffraction technique. The ionic currents near the surface of metallography were measured by the Scanning Vibrating Electrode Technique (SVET) and performed to evaluate the intergranular corrosion (IGC) resistance based on corrosion current density. The volume fractions of ferrite and austenite and the grain boundary misorientation angle affect the IGC sensitivity of the welded joints. The relationship between the grain boundary misorientation angle of the austenite and corrosion resistance was analyzed. When the weld metal was shielded with nitrogen, and the volume fraction of austenite and the frequency of Σ3 coincidence site lattice boundary in the weld was increased. The misorientation angle distribution in the austenite and the frequency of Σ3 coincidence site lattice boundary influence the IGC resistance of the welded joints.

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13

MADHUSOODHANAN, T., SAMIT MANDAL, M. P. SATHYAVATHIAMMA, RAMANI, N. G. PUTTASWAMY, T. S. MUDHOLE, A. MANDAL, D. K. AVASTHI, S. K. DATTA та R. SHYAM. "WIDE-ANGLE α-t COINCIDENCE MEASUREMENT IN THE BREAKUP OF 7Li ON 27Al". International Journal of Modern Physics E 08, № 04 (серпень 1999): 347–54. http://dx.doi.org/10.1142/s0218301399000252.

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We have performed wide-angle in-plane coincidence measurements of the alpha particles and tritons emitted in the 48-MeV 7 Li projectile breakup reaction on 27 Al . The data have been analyzed using the post-form distorted-wave Born-approximation (DWBA) theory of breakup reactions where Coulomb and nuclear breakup as well as their interference terms are included. The theory is able to provide a good description of the experimental data particularly at large relative angles between the fragments. The interference between the Coulomb and nuclear breakup modes is found to be significant.

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14

Molodov, Dmitri A., Tatiana Gorkaya, and Günter Gottstein. "Observation of Stress-Driven Migration of Specific Planar Grain Boundaries in Al Bicrystals." Materials Science Forum 706-709 (January 2012): 2886–91. http://dx.doi.org/10.4028/www.scientific.net/msf.706-709.2886.

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Stress induced grain boundary migration was experimentally investigated in aluminum bicrystals. Migration of planar symmetrical <100> and <111> tilt boundaries under a shear stress was observed to be accompanied by a lateral translation of the adjacent grains. This coupling proved to be the typical migration mode for all investigated boundaries, no matter whether low-or high angle, low Σ CSL coincidence or non-coincidence boundary. The migration-shear coupling was also observed for asymmetrical tilt boundaries. Measurements of the temperature dependence of coupled boundary migration revealed that there is a specific misorientation dependence of the migration activation parameters. Contrary to expectations, a high angle Σ7 tilt boundary moved under an applied stress, but produced practically no shear during its migration.

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15

Eloeva, Fatima. "Woman at the Ball. “Anna in the Neck” by Anton Chekhov and “The Psychology of a Husband from Syros” by Emmanuel Roidis: An Attempt of Comparison." Literatūra 63, no. 2 (November 22, 2021): 54–69. http://dx.doi.org/10.15388/litera.2021.63.2.4.

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The paper presents the first attempt to compare two short stories – Anna in the Neck by Anton Chekhov and a well-known short story by the Greek author Emmanuel Roidis Psychology of a Husband from Syros. Both texts were published at the same time (in 1895) and are considered to be masterpieces. The initial motivation for such textual analysis became almost a complete coincidence between the plots of the two stories. A series of telling coincidences and contradictions observed between the analyzed stories require some kind of explanation which will allow us to view both texts from the different angle. The paper aims to determine the correlation between the writers’ biographies and the personality traits with the characteristics of the protagonists and the style of story telling.

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16

Ushigami, Y., T. Kubota, and N. Takahashi. "Mechanism of Orientation Selectivity During Grain Growth of Secondary Recrystallization in Fe-3%Si Alloy." Textures and Microstructures 32, no. 1-4 (January 1, 1999): 137–51. http://dx.doi.org/10.1155/tsm.32.137.

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Selective growth of {110}〈001〉 grains in the temperature gradient annealing has been studied in Fe–3%Si alloy. As grains grow, the average deviation angle from the ideal {110}〈001〉 orientation becomes smaller and orientation distribution changes corresponding to that of coincidence grains in the matrix. Secondary recrystallization temperature depends on the orientation of secondary recrystallized grain and sharper {110} 〈001〉 grains grow preferentially at lower temperatures.These phenomena are explained by modified Hillert's model of grain growth. Interfacial energy of coincidence boundary is lower than that of general boundary. Therefore, sharper {110}〈001〉 grains, which have higher frequency of coincidence grains in the primary recrystallized matrix, suffer lower pinning effect from the second phase particles and thus grow preferentially at lower temperatures.

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17

Hansford, G. M. "Phase-targeted X-ray diffraction." Journal of Applied Crystallography 49, no. 5 (September 1, 2016): 1561–71. http://dx.doi.org/10.1107/s1600576716011936.

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A powder X-ray diffraction (XRD) method to enhance the signal of a specific crystalline phase within a mixture is presented for the first time. Specificity to the targeted phase relies on finding coincidences in the ratios of crystal d spacings and the ratios of elemental characteristic X-ray energies. Such coincidences can be exploited so that the two crystal planes diffract through the same scattering angle at two different X-ray energies. An energy-resolving detector placed at the appropriate scattering angle will detect a significantly enhanced signal at these energies if the target mineral or phase is present in the sample. When implemented using high scattering angles, for example 2θ > 150°, the method is tolerant to sample morphology and distance on the scale of ∼2 mm. The principle of the method is demonstrated experimentally using Pd Lα1 and Pd Lβ1 emission lines to enhance the diffraction signal of quartz. Both a pure quartz powder pellet and an unprepared mudstone rock specimen are used to test and develop the phase-targeted method. The technique is further demonstrated in the sensitive detection of retained austenite in steel samples using a combination of In Lβ1 and Ti Kβ emission lines. For both these examples it is also shown how the use of an attenuating foil, with an absorption edge close to and above the higher-energy characteristic X-ray line, can serve to isolate to some degree the coincidence signals from other fluorescence and diffraction peaks in the detected spectrum. The phase-targeted XRD technique is suitable for implementation using low-cost off-the-shelf components in a handheld or in-line instrument format.

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18

Vacik, Jiri, Vladimir Hnatowicz, and Ulli Köster. "Study of Neutron Induced Reactions on 7Be Using Large Angle Coincidence Spectroscopy." Physics Procedia 66 (2015): 520–23. http://dx.doi.org/10.1016/j.phpro.2015.05.068.

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19

Nedjadi, Youcef, Claude Bailat, Yvan Caffari, and François Bochud. "Standardisation of 18F by a coincidence method using full solid angle detectors." Applied Radiation and Isotopes 68, no. 7-8 (July 2010): 1309–13. http://dx.doi.org/10.1016/j.apradiso.2010.01.008.

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20

Freitas, Benedito Viana, Izabel Cristina Vieira De Oliveira, Pedrita Mara do Espírito Santo Souza, Heloíza Viana Freitas de Melo, Pedro César Fernandes dos Santos, and Raquel Soares Melo Leite Mouzinho. "Tratamento de má oclusão de Classe III subdivisão com mordida cruzada posterior unilateral através da técnica multiloop edgewise archwire (MEAW) – relato de caso." Orthodontic Science and Practice 14, no. 56 (2021): 58–66. http://dx.doi.org/10.24077/2021;1456-5866.

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The aim of this study was to report a clinical case of treatment of Class III subdivision malocclusion with unilateral posterior crossbite using the Multiloop Edgewise Archwire (MEAW) technique. A 19-year-old male patient reported mandibular prognathism as the main complaint. He had Angle Class III malocclusion, unilateral posterior crossbite on the right side, top bite in the anterior region, non-coincident midlines and facial asymmetry. Due to the patients refusal of surgical treatment, dentoalveolar orthodontic compensation was proposed. The MEAW technique associated with 3/16” intermaxillary elastics were used. At the end of the treatment, a Class I occlusal relationship between canines and molars, correction of the unilateral posterior crossbite and coincidence between the midlines was obtained. The MEAW technique was effective in correcting Class III subdivision malocclusion and unilateral posterior crossbite.

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21

Mu, Y. X., G. Q. Zhou, X. Zhou, J. Gao, and X. Y. Peng. "HPR AND OPK ANGLE ELEMENT CONVERSION METHOD BASED ON AIRBORNE LIDAR ALIGNMENT AXIS ERROR CALIBRATION." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLII-3/W10 (February 7, 2020): 71–75. http://dx.doi.org/10.5194/isprs-archives-xlii-3-w10-71-2020.

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Abstract. This paper mainly uses manual calibration technology to check the elements Yaw, Pitch and Roll (YPR) in the LiDAR DGPS/IMU system and obtained the error value. Combined with the error angle, the external azimuth angle elements Kappa, Omega and Phi required by photogrammetry are obtained. The paper points out that the placement angle error will have a serious impact on the LiDAR foot position. Therefore, this paper puts forward a method to check the placement angle of the steeple roof and flat straight highway, and gives the design scheme of the optimized route to reduce the number of flights. This paper focuses on the specific process of YPR calibration, and gives a mathematical calibration model based on the influence of attitude angles Yaw, Pitch and Roll on the LiDAR foot during the flight. The placement angle error is obtained after the calibration, and the error angle matrix is used to convert the elements YPR and OPK. After checking and error correction, the point cloud obtained from adjacent airlines have achieved better coincidence effect. The experimental results show that the theory and method of YPR element calibration are correct and feasible, which simplifies the conversion process of YPR and OPK. Compared with the traditional calibration method that requires control points, this method can greatly improve the efficiency and reliability of the inspection.

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22

Szilner, Suzana, Lorenzo Corradi, Giovanni Pollarolo, Giulia Colucci, Petra Čolović, Enrico Fioretto, Franco Galtarossa, et al. "Recent studies of heavy ion transfer reactions using large solid angle spectrometers." EPJ Web of Conferences 223 (2019): 01064. http://dx.doi.org/10.1051/epjconf/201922301064.

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We present selected results recently obtained in the study of heavy ion transfer reactions at energies close to the Coulomb barrier by employing the large solid angle magnetic spectrometer PRISMA. We discuss the production of neutron-rich heavy nuclei via multinucleon transfer processes and the related effects of secondary processes, in particular nucleon evaporation, studied in a high resolution kinematic coincidence experiment. We also present the recent results in the studies of neutron-neutron correlations for closed shell and superfluid systems.

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23

Frawley, A. D., L. H. Wright, R. C. Kline, E. P. Gavathas, and L. C. Dennis. "A large solid angle, high stopping power Bragg curve spectrometer for coincidence measurements." Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 306, no. 3 (September 1991): 512–23. http://dx.doi.org/10.1016/0168-9002(91)90045-r.

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24

Zheng, Wenjie, Shanxin Ruan, Yue Yang, Lin He, and Shiyi Chen. "Image-based modelling of the skin-friction coefficient in compressible boundary-layer transition." Journal of Fluid Mechanics 875 (July 26, 2019): 1175–203. http://dx.doi.org/10.1017/jfm.2019.535.

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We develop a model of the skin-friction coefficient based on scalar images in the compressible, spatially evolving boundary-layer transition. The images are extracted from a passive scalar field by a sliding window filter on the streamwise and wall-normal plane. The multi-scale and multi-directional geometric analysis is applied to characterize the averaged inclination angle of spatially evolving filtered component fields at different scales ranging from a boundary-layer thickness to several viscous length scales. In general, the averaged inclination angles increase along the streamwise direction, and the variation of the angles for large-scale structures is smaller than that for small-scale structures. Inspired by the coincidence of the increasing averaged inclination angle and the rise of the skin-friction coefficient, we propose a simple image-based model of the skin-friction coefficient. The model blends empirical formulae of the skin-friction coefficient in laminar and fully developed turbulent regions using the normalized averaged inclination angle of scalar structures at intermediate and small scales. The model prediction calculated from scalar images is validated by the results from the direct numerical simulation at two Mach numbers, 2.25 and 6, and the relative error can be less than 15 %.

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25

Zheng, Hongyu, and Shuo Yang. "Research on race car steering geometry considering tire side slip angle." Proceedings of the Institution of Mechanical Engineers, Part P: Journal of Sports Engineering and Technology 234, no. 1 (September 9, 2019): 72–87. http://dx.doi.org/10.1177/1754337119872417.

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The steering trapezoid designed according to the Ackermann steering geometry potentially causes excessive tire wear and affects the steering performance due to the large tire deformation resulting from large lateral acceleration. To address these problems, this article introduces a design method for a race car steering system that considers the tire side slip angles to optimize the target steering angle relation. First, a racing path was planned by genetic algorithm according to the given race track and race car driver characteristics. Next, the objective function of the ideal steering angle relation was constructed by introducing the Ackermann correction coefficient and establishing the modified Ackermann steering geometry model, considering the tire side slip angle. Then, a data acquisition experiment was designed, and the Ackermann correction coefficient was identified by the proposed simulation algorithm. Finally, the coincidence degree of wheel steering centers was defined as the evaluation index, which can be used to describe and evaluate the performance of the coordination for wheels’ movement. Simulation results show that the design method of the steering system effectively improves the handling stability of the race car and reduces the tire leaning-grind.

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26

Latifi, Kujtim, Eduardo G. Moros, Geoffrey Zhang, Louis Harrison, and Vladimir Feygelman. "A Method to Determine the Coincidence of MRI-Guided Linac Radiation and Magnetic Isocenters." Technology in Cancer Research & Treatment 18 (January 1, 2019): 153303381987798. http://dx.doi.org/10.1177/1533033819877986.

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To assure accurate treatment delivery on any image-guided radiotherapy system, the relative positions and walkout of the imaging and radiation isocenters must be periodically verified and kept within specified tolerances. In this work, we first validated the multiaxis ion chamber array as a tool for finding the radiation isocenter position of a magnetic resonance–guided linear accelerator. The treatment couch with the array on it was shifted in 0.2-mm increments and the reported beam center position was plotted against that shift and fitted to a straight line, in both X and Y directions. From the goodness-of-fit and intercepts of the regression lines, the accuracy and precision were conservatively estimated at 0.2 and 0.1 mm, respectively. This holds true whether the array is irradiated from the front or from the back, which allows efficient collecting the data from the 4 cardinal gantry angles with just 2 array positions. The average isocenter position agreed to within at most 0.4 mm along any cardinal axis with the linac vendor’s film-based procedure, and the maximum walkout radii were 0.32 mm and 0.53 mm, respectively. The magnetic resonance imaging isocenter walkout as a function of gantry angle was studied with 2 different phantoms, one employing a single fiducial at the center and another extracting the rigid displacement values from the distortion map fit of 523 fiducials dispersed over a large volume. The results were close between the 2 phantoms and demonstrated variation in the magnetic resonance imaging isocenter location as high as 1.3 mm along a single axis in the transverse plane. Verification of the magnetic resonance imaging isocenter location versus the gantry angle should be a part of quality assurance for magnetic resonance-guided linear accelerators.

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27

Kłosowski, Ł., M. Piwiński, D. Dziczek, K. Wiśniewska, and S. Chwirot. "Magnetic angle changer—a new device allowing extension of electron–photon coincidence measurements to arbitrarily large electron scattering angles." Measurement Science and Technology 18, no. 12 (November 1, 2007): 3801–10. http://dx.doi.org/10.1088/0957-0233/18/12/015.

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28

Becker, U. "Angle-resolved electron–electron and electron–ion coincidence spectroscopy: new tools for photoionization studies." Journal of Electron Spectroscopy and Related Phenomena 112, no. 1-3 (November 2000): 47–65. http://dx.doi.org/10.1016/s0368-2048(00)00202-4.

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29

Векман, А. В., та Б. Ф. Демьянов. "Базовые элементы структуры границ зерен наклона. Часть I. Ось разориентации [100]". Физика твердого тела 62, № 12 (2020): 1997. http://dx.doi.org/10.21883/ftt.2020.12.50201.397.

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The computer simulation methods have been applied to calculate structure and energy of symmetric tilt grain boundaries with the misorientation axis [100]. The calculations have been carried out with the use of the structural-vacancy model previously developed by the authors. The misorientation angles of grain boundaries of common type have varied from 0º up to 90º while the increment has amounted 1º. The reverse density of coincidence sites in special grain boundaries has amounted Σ ≤ 53. The calculations have been carried out with the use of the Morse pair potential and the Cleri-Rosato many-body potential. It is shown that the dependence of the energy of grain boundaries on the misorientation angle when calculated with different potentials has a similar form, and their structure does not depend on the choice of potential and is in good agreement with high-resolution electron microscopic images. Only one special grain boundary is distinguished on the energy curve which is Σ5(013). It has been found that the structure grain boundaries may be represented by a limited number of atomic groups that have been named basic structural units. The structure of low-angle grain boundaries with the misorientation angle less than 8º is described by alternation of basic structural units of D types and ideal crystal, while the structure of low-angle grain boundaries with the misorientation angle ranging from 8º up to 13º is described by alternation of structural units of C and D types, from 14º up to 23º – B and C types. High-angle grain boundaries in the range of misorientation angles from 24º up to 37º contain only of basic structural units of B types, from 38º to 50º – A and B, more than 50º – only A.

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30

Lee, Ken C., and Uwe Erb. "Grain boundaries and coincidence site lattices in the corneal nanonipple structure of the Mourning Cloak butterfly." Beilstein Journal of Nanotechnology 4 (May 2, 2013): 292–99. http://dx.doi.org/10.3762/bjnano.4.32.

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In this study the highly ordered corneal nanonipple structure observed on the Mourning Cloak butterfly (Nymphalis antiopa) is analyzed with a particular emphasis on the high-angle grain-boundary-like defects that are observed between individual nanonipple crystals. It is shown that these grain boundaries are generated by rows of topological coordination defects, which create very specific misorientations between adjacent crystals. These specific orientations form coincidence site lattices, which (i) have unit cells larger than the unit cell in each individual crystal and (ii) extend from one crystal to the next, effectively creating order over areas larger than the individual crystals. A comparison to similar coincidence site lattices in engineering materials is made and the importance of such arrangements in terms of nipple packing density, corneal lens curvature and potential optical properties is discussed.

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31

Zherebtsov, Sergey V., Egor A. Kudryavtsev, and Gennady A. Salishchev. "Mechanisms of Microstructure Refinement in Titanium during “abc” Deformation at 400°C." Materials Science Forum 667-669 (December 2010): 439–44. http://dx.doi.org/10.4028/www.scientific.net/msf.667-669.439.

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Mechanical behavior and microstructure evolution of commercial pure titanium during successive compressions of samples along three orthogonal directions (or so-called “abc” deformation) at 400°C and strain rate 10-3s-1 were studied. The cumulative S- curve demonstrates a steady state flow stage following the intensive strengthening. The microstructure evolution of titanium during first increments of “abc” deformation is associated with twinning and shear deformation. Further deformation results in microstructure refinement due to transformation of coincidence site lattice twin boundaries to high-angle arbitrary ones and formation of high-angle deformation induced boundaries. Another mechanism of new grains formation is continuous dynamic recrystallization.

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32

Ryde, Lena, W. Bevis Hutchinson, and Tomoji Kumano. "Grain Boundaries with High Misorientation and Low Mobility." Materials Science Forum 467-470 (October 2004): 739–44. http://dx.doi.org/10.4028/www.scientific.net/msf.467-470.739.

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Island grains have been studied in iron samples that had been treated by critical-strainannealing and in commercial silicon iron alloy sheets after incomplete secondary recrystallisation. Such islands remain behind because their boundaries have such a low mobility that the grains cannot shrink away in the time available during annealing. Misorientations of these islands in relation to the grains surrounding them were measured using EBSD. Similar results were observed in both materials. A small number of low angle boundaries were found and also many twin boundaries. The most remarkable observation, however, was the presence of many general high angle boundaries that did not correspond to any evident coincidence relation.

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33

Li, Guo Ping, Yan Bin Gao, Ting Jun Wang, and Lian Wu Guan. "Error Auto-Compensation Methods of Improved Single-Axial Rotation INS." Advanced Materials Research 791-793 (September 2013): 1046–49. http://dx.doi.org/10.4028/www.scientific.net/amr.791-793.1046.

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An Auto-Compensation of inertial navigation system (INS) based on improved single-axis rotation has been proposed in the paper. Inertial Measurement Unit (IMU) is tilt mounted, e.g. neither perpendicularly, nor coaxially, with the rotation axis. Analysis and derivation show that this angle arrangement of IMU can restrain the expansion of the system errors caused by IMU. Simulations demonstrated the coincidence of the theoretical analysis and the system performances

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34

Ii, Seiichiro, Motoki Hishida, Naoki Takata, Kenichi Ikeda, Hideharu Nakashima, and Nobuhiro Tsuji. "Grain Boundary Structures of ARB Processed Aluminum." Materials Science Forum 584-586 (June 2008): 716–21. http://dx.doi.org/10.4028/www.scientific.net/msf.584-586.716.

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Grain boundary structures in the commercial purity aluminum (1100Al) highly deformed by the accumulative roll bonding (ARB) process was observed by using conventional transmission electron microscopy (CTEM) and high resolution transmission electron microscopy (HRTEM). In the low angle grain boundary with a tilt angle (2θ) of 2.1o consisted of the periodic dislocations array, the interval of those dislocations could be explained by the dislocation model for grain boundary. However, the dense dislocation region locally existed at the vicinity of the low angle boundary. On the other hand, we also observed the high angle grain boundary of which the common axis and 2θ was <110> and 125.9o, respectively. In this grain boundary, we could describe the boundary configuration in terms of the combination of the kite-shaped structure unit characterized by Σ11 coincidence boundary with the 2θ of 129.52o around <110> and the additional dislocations to compensate the difference of the actual and geometrically coincided one.

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35

Chen, H., Y. X. Chen, Q. S. Wei, and Y. S. Shi. "Effect of Gravity on Repose Angle and Contact Forces of Particulate Pile Composed of Non-monodispersed Particles." International Journal of Aerospace Engineering 2019 (February 4, 2019): 1–10. http://dx.doi.org/10.1155/2019/8513149.

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Evaluating the repose angle of granular materials under different kinds of gravitational conditions is essential for in situ resource exploration on surfaces of other Earth-like planets in the next decades. The forming process of particulate pile under different kinds of gravitational accelerations was simulated by three-dimensional discrete element method (DEM), where the particulate piles composed of normally distributed particles and lognormally distributed particles were considered, respectively. The effects of gravity on the repose angle and contact forces of the particulate pile were investigated. The results show that, for particulate pile composed of normally or lognormally distributed particles, the effect of gravity force on the repose angle is ignorable. For particles with a certain kind of size distribution, the distribution functions of normalized contact forces in the particulate pile under different gravity accelerations show to be in mutual coincidence. No obvious effect of the particle size distribution on the relation between the gravity acceleration and repose angle is observed.

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36

Kłosowski, Ł., M. Piwiski, D. Dziczek, K. Wiśniewska, M. Zubek, and S. Chwirot. "Coincidence investigation of inelastic electron–atom collisions with magnetic selection of scattering angle – feasibility study." European Physical Journal Special Topics 144, no. 1 (May 2007): 173–77. http://dx.doi.org/10.1140/epjst/e2007-00123-x.

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37

Balpardo, C., M. E. Capoulat, D. Rodrigues, and P. Arenillas. "Standardization of 241Am by digital coincidence counting, liquid scintillation counting and defined solid angle counting." Applied Radiation and Isotopes 68, no. 7-8 (July 2010): 1358–61. http://dx.doi.org/10.1016/j.apradiso.2009.12.010.

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38

Watanabe, Tadao, Kouichi Obara та Sadahiro Tsurekawa. "In-Situ Observations on Interphase Boundary Migration and Grain Growth during α/γ Phase Transformation in Iron Alloys". Materials Science Forum 467-470 (жовтень 2004): 819–24. http://dx.doi.org/10.4028/www.scientific.net/msf.467-470.819.

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In-situ observations of a/g phase transformation were made to study the effect of grain boundary microstructure of the generation of a new phase and the migration of a/g interphase boundaries in an Iron-4.2at.%Cr alloy. It was found that triple junctions with more random boundaries could be the primary nucleation sites, while triple junctions with low angle and low S coincidence boundaries did not play a role as preferential sites. The migration of a/g interphase boundaries during heating across the transformation temperature showed the two stage behaviour characterized first by a stage with a migration velocity of 0.33-0.75µm/s and secondly a stage with 3.7-7.6 µm/s. It was also found that abnormal grain growth and a high density of S3 coincidence boundaries could occur in the a/bcc phase after cycling of a/g/ a phase transformation.

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39

Saitoh, Ken-ichi, Kohei Kuramitsu, Tomohiro Sato, Masanori Takuma, and Yoshimasa Takahashi. "Molecular Dynamics Study on Deformation Mechanism of Grain Boundaries in Magnesium Crystal: Based on Coincidence Site Lattice Theory." Journal of Materials 2018 (August 6, 2018): 1–10. http://dx.doi.org/10.1155/2018/4153464.

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As for magnesium (Mg) alloys, it has been noted that they are inferior to plastic deformation, but improvement in the mechanical properties by further refinement of grain size has been recently suggested. It means the importance of atomistic view of polycrystalline interface of Mg crystal. In this study, to discuss the deformation mechanism of polycrystalline Mg, atomistic grain boundary (GB) models by using coincidence site lattice (CSL) theory are constructed and are simulated for their relaxed and deformatted structures. First, GB structures in which the axis of rotation is in [11¯00] direction are relaxed at 10 Kelvin, and the GB energies are evaluated. Then, the deformation mechanism of each GB model under uniaxial tensile loading is observed by using the molecular dynamics (MD) method. The present MD simulations are based on embedded atom method (EAM) potential for Mg crystal. As a result, we were able to observe atomistically a variety of GB structures and to recognize significant difference in deformation mechanism between low-angle GBs and high-angle GBs. A close scrutiny is made on phenomena of dislocation emission processes peculiar to each atomistic local structure in high-angle GBs.

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40

Chen, Dun, Guoyu Li, Xiaodong Zhao, Wei Ma, Zhiwei Zhou, Yanhu Mu, Zejin Lai, and Tuo Chen. "Experimental Study on the Anisotropy and Non-coaxiality of Frozen Standard Sand under Different Principal Stress Directions." Geofluids 2022 (May 14, 2022): 1–15. http://dx.doi.org/10.1155/2022/1585324.

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Owing to the limitations of the apparatus, the influence of its principal stress direction on the anisotropic behavior and non-coaxiality of frozen soil has not been fully considered in previous studies. At a temperature of -10°C, a series of hollow cylinder tests for frozen standard sand (FSS) was conducted under different directional angles of major principal stress and mean principal stresses in this study. The experimental results indicate that the stress-strain-strength anisotropy and non-coaxiality of the FSS are highly dependent on the principal stress direction. The stress components of the FSS vary linearly with increasing shear stress at different directional angles of the major principal stress and mean principal stresses. With a linear increase in shear stress, the strain components of the FSS exhibited a nonlinear increasing trend. The FSS strength gradually decreased as the directional angle of the major principal stress and the mean principal stresses in the test range increased. Under the different principal stress directions, the non-coaxiality of the FSS, non-coincidence of the direction of the principal strain increment and the principal stress direction, were observed. The directions of the principal strain increment and principal stress gradually tended to be coaxial as shear stress increased. Although the non-coaxial angle of the FSS increased gradually with an increase in the directional angles of the major principal stress, it did not change with the change in the mean principal stress. The non-coaxial angle of the FSS was observed to be as large as 35° in the early stage of shearing under different mean principal stresses.

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41

Pastukhov, Vladimir I., Sergey S. Khvostov, and Mikhail L. Lobanov. "Effect of Grain Boundaries Type on Carbides Precipitates in Tempered Martensite." Materials Science Forum 946 (February 2019): 368–73. http://dx.doi.org/10.4028/www.scientific.net/msf.946.368.

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Different types of carbide phases and regions of their precipitation in tempered martensite of austenitic steel have been investigated with orientation microscopy (EBSD) and electron microprobe analysis. The steel structure consisted of large grains of high-temperature ferrite (~ 15%), without visible mesostructured, and martensite packages with a great number of low-angle boundaries. High-angle boundary spectrum with the most prominent coincidence site lattice (CSL) boundaries, Σ3, Σ11, Σ25b, Σ33с Σ41с, is typical for martensite. This spectrum, resulted from austenite transformation by shear mechanism according to orientation relationships (OR), intermediate between Kurdjumov-Sachs (K-S) and Nishiyama-Wassermann (N-W). In the structure two types of carbide precipitates were observed: large MC [~ NbC] along the boundaries of former austenite grains, and dispersed M23C6 [~ (W,Mo)2(Cr,Fe)21C6] predominantly along the boundaries in martensite packages. It has been shown that under martensite tempering M23C6 precipitation was mainly at high-angle intergranular boundaries. Carbide almost did not precipitate at low-angle and special CSL Σ3 boundaries. A few carbides were detected at special CSL boundaries, Σ11, Σ25b, Σ33с Σ41с.

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42

Timofeev, Lev, and Anatoly Ivanov. "EAS detection by wide-angle cherenkov telescopes at the Yakutsk array." EPJ Web of Conferences 208 (2019): 08015. http://dx.doi.org/10.1051/epjconf/201920808015.

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A proposed new method for measuring the Cherenkov light from extensive air showers (EAS) of cosmic rays (CR), which allows to determine not only the primary particle energy and angle of arrival, but also the parameters of the shower in the atmosphere - the maximum depth and “age”. For measurements, it is proposed to use Cherenkov light produced by EAS in a ground network of wide-angle telescopes, which are separated from each other by a distance 100-300 m depending on the total number of telescopes operating in coincidence, acting autonomously, or includes a detector of the charged components, radio waves, etc. as part of the EAS. The energy measurement and CR angle of arrival, data on the depth of the maximum and the associated mass of the primary particle generating the EAS is particularly important in the study of galactic cosmic rays for E> 1014 eV, where currently there are no direct measurements of the maximum depth of the EAS.

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43

Nomura, Miki, Sing-Yun Lee, and James B. Adams. "Vacancy diffusion along twist grain boundaries in copper." Journal of Materials Research 6, no. 1 (January 1991): 1–4. http://dx.doi.org/10.1557/jmr.1991.0001.

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Vacancy diffusion along two different high-angle twist grain boundaries (Σ5 and Σ13) was studied using the Embedded Atom Method (EAM). Vacancy formation energies in all the possible sites were calculated and found to be directly related to the degree of coincidence with the neighboring crystal planes. Optimal migration paths and migration energies were determined and found to be very low. The activation energies for self-diffusion at the boundaries were found to be less than half of the bulk value.

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44

Sajedi, S., L. Bläckberg, S. Majewski, and H. Sabet. "Limited-angle TOF-PET for intraoperative surgical applications: proof of concept and first experimental data." Journal of Instrumentation 17, no. 01 (January 1, 2022): T01002. http://dx.doi.org/10.1088/1748-0221/17/01/t01002.

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Abstract The intraoperative gamma probe (IPG) based on single gamma-ray detection remains the current gold standard modality for sentinel lymph node identification and tumor removal in cancer patients. However, IPGs do not meet the <5% false negative rate (FNR) requirement, a key metric suggested by the American Society of Clinical Oncology (ASCO). We aim to reduce FNR by using time of flight (TOF) PET detector technology in limited angle geometry system by using only two detector panels in coincidence. For proof of concept, we used two Hamamatsu TOF PET detector modules (C13500-4075YC-12) featuring 12× 12 arrays of 4.14× 4.14× 20 mm3 LFS crystal pixels with 4.2 mm pitch and coupled one-one to silicon photomultiplier (SiPM) pixels. The measured detector coincidence timing resolution (CTR) was 271 ps FWHM for the whole detector. We 3D printed lesion phantom containing spheres 2–10 mm in diameter, representing lymph nodes, and placed it inside a 10-liter warm background water phantom. Experimental results showed that with subminute data acquisition, 6 mm diameter spheres could be identified in the image when a lesion phantom with a 10:1 activity ratio to background was used. The simulation results were in good agreement with the experimental data by resolving 6 mm diameter spherical lesions with a 60 second acquisition time in a 25 cm deep background water phantom with a 10:1 activity ratio. As expected, the image quality improved as the CTR improved in the simulation and with decreasing background water phantom depth or increasing lesion-to-background activity ratio in the experiment. With the results presented here, we concluded that using a limited angle TOF PET detector system is a major step forward for intraoperative applications in that lesion detectability is beyond what conventional gamma- and NIR-based probes could achieve.

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45

Nomura, Miki, and James B. Adams. "Self-diffusion along twist grain boundaries in Cu." Journal of Materials Research 7, no. 12 (December 1992): 3202–12. http://dx.doi.org/10.1557/jmr.1992.3202.

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In a previous paper we studied vacancy diffusion in two high-angle twist grain boundaries in Cu, using the EAM. In this paper, we discuss vacancy diffusion along four additional twist grain boundaries, from 8.8–43.6°. Vacancy formation energies in all the possible sites were calculated (0.14–1.42 eV) and found to be directly related to the degree of coincidence with the neighboring crystal planes. The optimal migration paths were found to coincide with the screw dislocations which comprise the boundary. Vacancy migration energies were found to be low (0.02–0.52 eV). The activation energies for self-diffusion at the boundaries were found to be less than half of the bulk value, in general agreement with experiment. Calculated diffusion rates, δD, for medium-high angle twist grain boundaries were in reasonable agreement with experimental data for polycrystalline material. Diffusion rates were found to decrease with increasing twist angle, in contrast with two sets of conflicting experimental data.

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46

Alekseev, V. A., V. G. Kostin, A. V. Usoltseva, V. P. Usoltsev, and S. I. Yuran. "Expanding of Excimer Laser Photoablation’s Functionality in Ophthalmology." Devices and Methods of Measurements 12, no. 3 (October 15, 2021): 175–82. http://dx.doi.org/10.21122/2220-9506-2021-12-3-175-182.

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One of the significant weaknesses of excimer laser-based vision correction devices is the difficulty of achieving a required change in the refractive properties of the cornea to sharply focus the image on the retina with distance from the working area (ablation zone) center to the periphery due to a change in the laser beam incidence angle. The study is aimed at improving the quality of laser action on the eye cornea by introducing an optical corrective system into the existing excimer laser vision correction equipment, ensuring the coincidence of the direction of the laser beam incidence on the corneal surface with the normal.It has been shown that the greater the reflection coefficient, the lower the absorbed energy, and the shallower the laser radiation penetration and ablation depths, which reduces the laser action opportunities and quality. When using excimer laser vision correction devices, it has been proposed to change the angle of the laser beam incidence on the cornea with a distance from the working area (ablation zone) center to the periphery during the surgery by introducing an optical corrective system based on a lightweight controllable and movable mirror, which allows achieving the coincidence of the direction of the laser beam incidence on the corneal surface with the normal.The studies have shown that the coincidence of the laser beam incidence on the corneal surface at any point with the normal when using a priori data on the specifics of the patient's eye allows expanding the functional opportunities of excimer laser photoablation, i. e., expand the ablation zone by 30 % and eliminate the possibility of errors caused by the human factor. The technique proposed can be used for excimer laser vision correction according to PRK, LASIK, Femto-LASIK, and other methods. To implement this approach, a patented excimer laser vision correction unit has been proposed with a PCcontrolled optical shaping system comprising galvo motor platforms and galvo mirrors installed on them.

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47

Chen, L., G. J. Yuan, J. G. Xu, F. Guo, and N. Pang. "Effect of Trench Aspect Ratio on Microstructure and Texture in Damascene Cu Interconnects." Materials Science Forum 706-709 (January 2012): 2605–10. http://dx.doi.org/10.4028/www.scientific.net/msf.706-709.2605.

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The effect of trench aspect ratio and line spacing on microstructure and texture in annealed damascene Cu interconnects has been investigated. The X-ray diffraction (XRD) and electron backscatter diffraction (EBSD) analyses of Cu lines, showed a preferred {111} orientation and the trenches reduce the proportion of high-angle grain boundaries and increase the fraction of coincidence site lattice (CSL) grain boundaries, comparing with the Cu blanket film. In addition, both trench aspect ratio and line spacing can largely affect the microstructure and texture in annealed damascene Cu interconnects.

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48

NEKRASOV, M. L. "MODIFIED PERTURBATION THEORY FOR ANGULAR DISTRIBUTION IN W-PAIR PRODUCTION." Modern Physics Letters A 27, no. 32 (October 11, 2012): 1250195. http://dx.doi.org/10.1142/s0217732312501957.

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We examine the capabilities of the modified perturbation theory (MPT) for description of W-pair production and decay in e+ e- annihilation. In a model with Dyson-resummed propagators of unstable particles, we calculate even and odd contributions to the distribution in the cosine of the W- production angle relative to the e- beam. On comparing the results of calculations in the NNLO approximation of MPT with the exact results in the model, a coincidence of outcomes at the ILC energies is detected at the per-mille level.

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49

Padmanabhan, Preethi, Chao Zhang, and Edoardo Charbon. "Modeling and Analysis of a Direct Time-of-Flight Sensor Architecture for LiDAR Applications." Sensors 19, no. 24 (December 11, 2019): 5464. http://dx.doi.org/10.3390/s19245464.

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Direct time-of-flight (DTOF) is a prominent depth sensing method in light detection and ranging (LiDAR) applications. Single-photon avalanche diode (SPAD) arrays integrated in DTOF sensors have demonstrated excellent ranging and 3D imaging capabilities, making them promising candidates for LiDARs. However, high background noise due to solar exposure limits their performance and degrades the signal-to-background noise ratio (SBR). Noise-filtering techniques based on coincidence detection and time-gating have been implemented to mitigate this challenge but 3D imaging of a wide dynamic range scene is an ongoing issue. In this paper, we propose a coincidence-based DTOF sensor architecture to address the aforementioned challenges. The architecture is analyzed using a probabilistic model and simulation. A flash LiDAR setup is simulated with typical operating conditions of a wide angle field-of-view (FOV = 40 ° ) in a 50 klux ambient light assumption. Single-point ranging simulations are obtained for distances up to 150 m using the DTOF model. An activity-dependent coincidence is proposed as a way to improve imaging of wide dynamic range targets. An example scene with targets ranging between 8–60% reflectivity is used to simulate the proposed method. The model predicts that a single threshold cannot yield an accurate reconstruction and a higher (lower) reflective target requires a higher (lower) coincidence threshold. Further, a pixel-clustering scheme is introduced, capable of providing multiple simultaneous timing information as a means to enhance throughput and reduce timing uncertainty. Example scenes are reconstructed to distinguish up to 4 distinct target peaks simulated with a resolution of 500 ps. Alternatively, a time-gating mode is simulated where in the DTOF sensor performs target-selective ranging. Simulation results show reconstruction of a 10% reflective target at 20 m in the presence of a retro-reflective equivalent with a 60% reflectivity at 5 m within the same FOV.

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50

Cai, Shan Le, and Yan Wei Cai. "Study on Free Shaving for Worm Type Shaving Cutter of Open Groove." Advanced Materials Research 591-593 (November 2012): 377–80. http://dx.doi.org/10.4028/www.scientific.net/amr.591-593.377.

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In order to solve the problem of tooth concave error appeared in the shaving course of non-modification disk-shaped shaving cutter, the worm type shaving cutter of open groove is studied. Firstly, the basic structure of the shaving cutter and the manufacturing process will be introduced in detail. The angle of front cutting edge is -30 ° or 30 °, and then the coincidence degree is approximately equal to 2, when the tool cut the gear in the direction of the oblique angle. Secondly, the tooth profile precision will be able to be achieved though circular grinding method based on both sides of the worm. Finally, the free shaving principle is discussed by analyzing the shaving movement, the drive speed and the cutting speed. According to the shaving gear experiment, the results show that the tooth precisions reach to the 6 grades.

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