Academic literature on the topic 'GR workbench'

This research work was performed to interpret the fabrication and mechanical characteristics of LM6/B4C and LM6/B4C/Gr aluminium matrix composites. The aluminium matrix composites were manufactured by reinforcing B4C particles with varying wt % of 3, 5, 7 using stir casting technique. LM6/B4C 7% composite was made hybrid by adding 2% Graphite into it. The presence of graphite in such composites provide the self-lubricating effect, replacing conventional sliding contacts (bearings, sheaves, pistons, pulleys) with them. This also helps to reduce the lubricating oil and fuel consumption along with environmental benefits reducing energy wastage in industrial and automotive components. The properties of the composites were collated with the base alloy to analyse the enhancement in mechanical characteristics that had been transmitted by the reinforcement particles to the composites. The specimen microstructure was inspected using an optical microscope to ensure the uniform distribution of reinforcement particles in the matrix. The piston was modelled in CREO and using ANSYS 14.5 workbench static structural analysis of LM6 alloy, LM6/B4C composite and LM6/B4C/Gr hybrid aluminium composites are executed. Compared to LM6 alloy, better static structural properties were obtained in composites and hybrid composite.

Background and Hypothesis: Autism Spectrum Disorder (ASD) is a common neurodevelopmental disorder with a prevalence of 2.76% among children ages 3-17 in the United States1. Some studies have linked total brain volume overgrowth or gyrification changes to ASD2,3,4. However, few have attempted to relate specific growth patterns to ASD. We hypothesize that regional differences in brain growth in subjects aged 12-24 months will correlate with diagnoses from the Autism Diagnostic Observation Schedule (ADOS). Project Methods: The subjects for this study came from the Infant Brain Imaging Study (IBIS)5. The CIVET pipeline was used to segment T1-weighted magnetic resonance images (MRIs) into surfaces using a non-linear classification method5,6,7. CIVET quality control outputs were used for validation and to select parameters for the tasks along with previous recommendations5,8. Analysis of Functional NeuroImages (AFNI) was used to convert the CIVET output format, and Connectome Workbench was used to calculate surface curvature. Using cortical reconstructions and surface curvatures from 12- and 24-month brains, anatomically-constrained Multimodal Surface Matching (aMSM) was applied to achieve point correspondence and generate individual cortical growth maps9,10. Results: Within the IBIS database, we found 38 individuals with ASD and 121 controls with T1weighted scans at both 12 and 24-month time points. Once individual growth maps have been generated for all subjects, Permutation Analysis of Linear Models (PALM)11 will be used to determine statistically significant differences in the cortical growth patterns of ASD versus control groups. Conclusion and Potential Impact: Research on autism may benefit from longitudinal studies of growth, as opposed to analysis of structural differences at later ages4. We concentrate on cortical growth before 24 months, which may serve as an earlier marker of ASD, when abnormal brain growth can be seen yet social deficits are not fully established5. [1] Zablotsky B, Black LI, Blumberg SJ. Estimated Prevalence of Children With Diagnosed Developmental Disabilities in the United States, 2014–2016. NCHS Data Brief 2017. https://www.cdc.gov/nchs/data/databriefs/db291.pdf (accessed April 29, 2019). [2] Libero LE, Schaer M, Li DD, Amaral DG, Nordahl CW. A Longitudinal Study of Local Gyrification Index in Young Boys With Autism Spectrum Disorder. Cereb Cortex. 2019;29(6):2575-87. [3] Raznahan A, Toro R, Daly E, Robertson D, Murphy C, Deeley Q, et al. Cortical anatomy in autism spectrum disorder: an in vivo MRI study on the effect of age. Cereb Cortex. 2010;20(6):1332-40. [4] Duret P, Samson F, Pinsard B, Barbeau EB, Bore A, Soulieres I, et al. Gyrification changes are related to cognitive strengths in autism. Neuroimage Clin. 2018;20:415-23. [5] Hazlett HC, Gu H, Munsell BC, Kim SH, Styner M, Wolff JJ, et al. Early brain development in infants at high risk for autism spectrum disorder. Nature. 2017;542(7641):348-51. [6] Shaw P, Malek M, Watson B, Sharp W, Evans A, Greenstein D. Development of cortical surface area and gyrification in attentiondeficit/hyperactivity disorder. Biol Psychiatry. 2012;72(3):191-7. [7] Ad-Dab’bagh, Y., Einarson, D., Lyttelton, O., Muehlboeck, J.-S., Mok, K., Ivanov, O., Vincent, R.D., Lepage, C., Lerch, J., Fombonne, E., and Evans, A.C. (2006). The CIVET Image-Processing Environment: A Fully Automated Comprehensive Pipeline for Anatomical Neuroimaging Research. In Proceedings of the 12th Annual Meeting of the Organization for Human Brain Mapping, M. Corbetta, ed. (Florence, Italy, NeuroImage). http://www.bic.mni.mcgill.ca/users/yaddab/Yasser-HBM2006-Poster.pdf [8] Shaw P, Kabani NJ, Lerch JP, Eckstrand K, Lenroot R, Gogtay N, et al. Neurodevelopmental trajectories of the human cerebral cortex. J Neurosci. 2008;28(14):3586-94. [9] Garcia KE, Robinson EC, Alexopoulos D, Dierker DL, Glasser MF, Coalson TS, et al. Dynamic patterns of cortical expansion during folding of the preterm human brain. Proc Natl Acad Sci U S A. 2018;115(12):3156-61. [10] Robinson EC, Garcia K, Glasser MF, Chen Z, Coalson TS, Makropoulos A, et al. Multimodal surface matching with higher-order smoothness constraints. Neuroimage. 2018;167:453-65. [11] Winkler AM, Ridgway GR, Webster MA, Smith SM, Nichols TE. Permutation inference for the general linear model. NeuroImage, 2014;92:381-397 (Open Access)

A numerical raytracer is developed for determining the optical appearance of distant objects in the curved spactimes of General Relativity. This raytracer employs the GRworkbench software to directly integrate the geodesic equation for light, using general techniques that could be applied to any asymptotically flat spacetime solution. The raytracer is used to investigate the appearance of the celestial sky around Kerr-Newman black holes with arbitrary electric charge and angular momentum. The results of this raytracer are compared with previous literature concerning the uncharged static Schwarzschild black hole geometry.