Deformed Shape Analysis of Elastic Shell of Circular Soft Robot

Abstract The scattering of plane steady-state sound waves from a viscous fluid-filled thin cylindrical shell weak- ened by a long linear slit and submerged in an ideal fluid is studied. For the description of vibrations of elastic objects the Kirchhoff-Love shell-theory approximation is used. An exact solution of this problem is obtained in the form of series with cylindrical harmonics. The numerical analysis is carried out for a steel shell filled with oil and immersed in seawater. The modules and phases of the scattering amplitudes versus the dimensionless wavenumber of the incident sound wave as well as directivity patterns of the scattered field are investigated taking into consideration the orientation of the slit on the elastic shell surface. The plots obtained show a considerable influence of the slit and viscous fluid filler on the diffraction process.

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Intermittent Failures in High Pin Count Packaging

ISTFA 2006: Conference Proceedings from the 32nd International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa2006p0109 ◽

2006 ◽

Author(s):

Ramesh Varma ◽

Richard Brooks ◽

Ronald Twist ◽

James Arnold ◽

Cleston Messick

Keyword(s):

Failure Analysis ◽

Shape Analysis ◽

State Of The Art ◽

Process Variation ◽

High Reliability ◽

Temperature Cycling ◽

Assembly Process ◽

System Failures ◽

Industrial Grade ◽

Corrective Actions

Abstract In a prequalification effort to evaluate the assembly process for the industrial grade high pin count devices for use in a high reliability application, one device exhibited characteristics that, without corrective actions and/or extensive screening, may lead to intermittent system failures and unacceptable reliability. Five methodologies confirmed this conclusion: (1) low post-decapsulation wire pull results; (2) bond shape analysis showed process variation; (3) Failure Analysis (FA) using state of the art equipment determined the root causes and verified the low wire pull results; (4) temperature cycling parts while monitoring, showed intermittent failures, and (5) parts tested from other vendors using the same techniques passed all limits.

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Deformation-based Statistical Shape Analysis of the Corpus Callosum in Mild Cognitive Impairment and Alzheimer’s Disease

Current Alzheimer Research ◽

10.2174/1567205015666180813145935 ◽

2018 ◽

Vol 15 (12) ◽

pp. 1151-1160 ◽

Cited By ~ 1

Author(s):

Zihan Jiang ◽

Huilin Yang ◽

Xiaoying Tang

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Cognitive Impairment ◽

Mild Cognitive Impairment ◽

Corpus Callosum ◽

Shape Analysis ◽

Disease Assessment ◽

Statistical Shape Analysis ◽

Superior Part ◽

Statistical Shape

Objective: In this study, we investigated the influence that the pathology of Alzheimer’s disease (AD) exerts upon the corpus callosum (CC) using a total of 325 mild cognitive impairment (MCI) subjects, 155 AD subjects, and 185 healthy control (HC) subjects. Method: Regionally-specific morphological CC abnormalities, as induced by AD, were quantified using a large deformation diffeomorphic metric curve mapping based statistical shape analysis pipeline. We also quantified the association between the CC shape phenotype and two cognitive measures; the Mini Mental State Examination (MMSE) and the Alzheimer’s Disease Assessment Scale-Cognitive Behavior Section (ADAS-cog). To identify AD-relevant areas, CC was sub-divided into three subregions; the genu, body, and splenium (gCC, bCC, and sCC). Results: We observed significant shape compressions in AD relative to that in HC, mainly concentrated on the superior part of CC, across all three sub-regions. The HC-vs-MCI shape abnormalities were also concentrated on the superior part, but mainly occurred on bCC and sCC. The significant MCI-vs-AD shape differences, however, were only detected in part of sCC. In the shape-cognition association, significant negative correlations to ADAS-cog were detected for shape deformations at regions belonging to gCC and sCC and significant positive correlations to MMSE at regions mainly belonging to sCC. Conclusion: Our results suggest that the callosal shape deformation patterns, especially those of sCC, linked tightly to the cognitive decline in AD, and are potentially a powerful biomarker for monitoring the progression of AD.

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Determination of the Accurate Values of the Rate Constant and Thermodynamic Parameters for the Rotation About the C(sp2)-C(aryl) Bond; Adamantan-1-yl 3-Bromo-2,4,6-trimethylphenyl Ketone

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19980955 ◽

1998 ◽

Vol 63 (7) ◽

pp. 955-966

Author(s):

Eva Přibylová ◽

Miroslav Holík

Keyword(s):

Thermodynamic Parameters ◽

Shape Analysis ◽

Rate Constants ◽

Line Shape ◽

Microsoft Excel ◽

Hindered Rotation ◽

H Nmr ◽

Line Shape Analysis ◽

Coalescence Temperature

Four programs for the 1H NMR line shape analysis: two commercial - Winkubo (Bruker) and DNMR5 (QCPE 165) and two written in our laboratory - Newton (in Microsoft Excel) and Simtex (in Matlab) have been tested in order to get highly accurate rate constants of the hindered rotation about a single bond. For this purpose four testing criteria were used, two of them were also developed by us. As supplementary determinations the rate constants obtained for the coalescence temperature and for the thermal racemization of chromatographically separated enantiomers were used which fitted well the temperature dependence of the rate constants determined by the line shape analysis. As a test compound adamantan-1-yl 3-bromo-2,4,6-trimethylphenyl ketone was prepared and studied. It was shown that supermodified simplex method used in our algorithm (Simtex), though time consuming, gives the most accurate values of the rate constants and consequently the calculated thermodynamic parameters Ea, ∆H≠, and ∆S≠ lay in relatively narrow confidence intervals.

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