93 research outputs found
NASTRAN data deck generation on the PC
Using two commercial programs an application was developed to aid in generating a run-ready NASTRAN data deck on the PC. Macros are used to access relevant reference material and card files while editing the deck. The application can be easily customized to suit individual or group needs
Finite Element Modeling of Ultrasonic Inspection of Weldments
High performance weldments for critical service applications require 100% inspection. Balanced against the adaptability of the ultrasonic method for automated inspection are the difficulties encountered with nonhomogeneous and anisotropic materials. This research utilizes crystals and bicrystals of nickel to model austenitic weld metal, where the anisotropy produces scattering and mode conversion, making detection and measurement of actual defects difficult.
Well characterized samples of Ni are produced in a levitation zone melting facility. Crystals in excess of 25 mm diameter and length are large enough to permit ultrasonic measurements of attenuation, wave speed, and spectral content. At the same time, the experiments are duplicated as finite element models for comparison purposes.
Finite element models permit easy description of boundary conditions, geometry, and loading. Direct integration of the wave equation is done with the Newmark-Beta and Wilson-Theta Methods. The usual problem with the large number of degress of freedom can be alleviated with the use of Guyan reduction.
Two-dimensional comparisons showing mode conversion and a plate with a flaw are made. The continued development of this computational tool should increase understanding of quantitative ultrasonic inspection
Co-rotational Formulation for Bonded Joint Finite Elements
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/97052/1/AIAA2012-1449.pd
To which world regions does the valenceâdominance model of social perception apply?
Over the past 10 years, Oosterhof and Todorovâs valenceâdominance model has emerged as the most prominent account of
how people evaluate faces on social dimensions. In this model, two dimensions (valence and dominance) underpin social
judgements of faces. Because this model has primarily been developed and tested in Western regions, it is unclear whether
these findings apply to other regions. We addressed this question by replicating Oosterhof and Todorovâs methodology across
11 world regions, 41 countries and 11,570 participants. When we used Oosterhof and Todorovâs original analysis strategy,
the valenceâdominance model generalized across regions. When we used an alternative methodology to allow for correlated
dimensions, we observed much less generalization. Collectively, these results suggest that, while the valenceâdominance
model generalizes very well across regions when dimensions are forced to be orthogonal, regional differences are revealed
when we use different extraction methods and correlate and rotate the dimension reduction solution.C.L. was supported by the Vienna Science and Technology Fund (WWTF VRG13-007);
L.M.D. was supported by ERC 647910 (KINSHIP); D.I.B. and N.I. received funding from
CONICET, Argentina; L.K., F.K. and Ă. Putz were supported by the European Social
Fund (EFOP-3.6.1.-16-2016-00004; âComprehensive Development for Implementing
Smart Specialization Strategies at the University of PĂ©csâ). K.U. and E. Vergauwe were
supported by a grant from the Swiss National Science Foundation (PZ00P1_154911 to E.
Vergauwe). T.G. is supported by the Social Sciences and Humanities Research Council
of Canada (SSHRC). M.A.V. was supported by grants 2016-T1/SOC-1395 (Comunidad
de Madrid) and PSI2017-85159-P (AEI/FEDER UE). K.B. was supported by a grant
from the National Science Centre, Poland (number 2015/19/D/HS6/00641). J. Bonick
and J.W.L. were supported by the Joep Lange Institute. G.B. was supported by the Slovak
Research and Development Agency (APVV-17-0418). H.I.J. and E.S. were supported
by a French National Research Agency âInvestissements dâAvenirâ programme grant
(ANR-15-IDEX-02). T.D.G. was supported by an Australian Government Research
Training Program Scholarship. The Raipur Group is thankful to: (1) the University
Grants Commission, New Delhi, India for the research grants received through its
SAP-DRS (Phase-III) scheme sanctioned to the School of Studies in Life Science;
and (2) the Center for Translational Chronobiology at the School of Studies in Life
Science, PRSU, Raipur, India for providing logistical support. K. Ask was supported by
a small grant from the Department of Psychology, University of Gothenburg. Y.Q. was
supported by grants from the Beijing Natural Science Foundation (5184035) and CAS
Key Laboratory of Behavioral Science, Institute of Psychology. N.A.C. was supported
by the National Science Foundation Graduate Research Fellowship (R010138018). We
acknowledge the following research assistants: J. Muriithi and J. Ngugi (United States
International University Africa); E. Adamo, D. Cafaro, V. Ciambrone, F. Dolce and E.
Tolomeo (Magna GrĂŠcia University of Catanzaro); E. De Stefano (University of Padova);
S. A. Escobar Abadia (University of Lincoln); L. E. Grimstad (Norwegian School of
Economics (NHH)); L. C. Zamora (Franklin and Marshall College); R. E. Liang and R.
C. Lo (Universiti Tunku Abdul Rahman); A. Short and L. Allen (Massey University, New
Zealand), A. AteĆ, E. GĂŒneĆ and S. Can Ăzdemir (BoÄaziçi University); I. Pedersen and T.
Roos (Ă
bo Akademi University); N. Paetz (Escuela de ComunicaciĂłn MĂłnica Herrera);
J. Green (University of Gothenburg); M. Krainz (University of Vienna, Austria); and B.
Todorova (University of Vienna, Austria). The funders had no role in study design, data
collection and analysis, decision to publish or preparation of the manuscript.https://www.nature.com/nathumbehav/am2023BiochemistryGeneticsMicrobiology and Plant Patholog
A new 6-node shear-deformable triangular plate/shell element for the analysis of spinning composite pretwisted plates
Hearing Outcomes after Partial Translabyrinthine Petrous Apicectomy for Petroclival Meningiomas
Objective:
Although various surgical approaches are currently used to achieve access to petroclival meningiomas (PMs), each approach has an associated risk of postoperative deterioration of cochlear function. The purpose of this study is to review our experience with the partial translabyrinthine petrous apicectomy (PTLPA) approach to PM, as well as of the use of intraoperative brainstem auditory-evoked response (BAER) in PM as a predictive tool for auditory outcomes.
Design:
Retrospective case review over a 15-year period (1995 to 2010).
Setting:
Tertiary academic referral center.
Participants:
Patients with petroclival meningioma (PM) treated with partial translabyrinthine petrous apicectomy (PTLPA) with documented pre- and postoperative cochlear nerve assessment.
Main Outcome Measures:
Pre- and postoperative hearing function and intraoperative BAER.
Results:
Seventy-two PMs were treated surgically during the time period. Six patients underwent PTLPA. All were female. Five lesions were located on the right and one on the left. Mean age was 53 years. All patients had serviceable hearing preoperatively. All patients had subtotal resections via the PTLPA approach. Three patients (50%) maintained serviceable hearing postoperatively. Intraoperative BAER tracings were available in three cases. Two patients had significant decline in their wave V latencies intraoperatively. Of these two patients, one patient developed unserviceable hearing postoperatively, while the other retained serviceable hearing. The third patient had negligible changes in BAER tracings but unserviceable hearing postoperatively.
Conclusion:
The PTLPA approach for petroclival meningiomas is a useful tool in skull base surgery. It affords similar exposure to facilitate extirpation to its more ablative counterpart (e.g., translabyrinthine) while allowing for equal preservation of auditory function likened to the traditional approaches (e.g., retrosigmoid and retrolabyrinthine approaches) in which exposure may be inadequate. Our experience with intraoperative BAER tracings suggests that further experience with this tool is necessary to determine its predictive value for hearing conservation
The use of displacement threshold for switching frequency strategy for structural vibration mitigation
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