Radial Deformation of Cylinders Due to Torsion

2012 ◽  
Vol 79 (6) ◽  
Author(s):  
Srikant Sekhar Padhee ◽  
Dineshkumar Harursampath
Keyword(s):  
Isotropic Material ◽  
Ad Hoc ◽  
Solid Mechanics ◽  
Transversely Isotropic ◽  
Analytic Solutions ◽  
Radial Deformation ◽  
Classical Literature ◽  
Cross Sectional ◽  
Closed Form Solutions ◽  
3D Elasticity

Classical literature on solid mechanics claims existence of radial deformation due to torsion but there is hardly any literature on analytic solutions capturing this phenomenon. This paper tries to solve this problem in an asymptotic sense using the variational asymptotic method (VAM). The method makes no ad hoc assumptions and hence asymptotic correctness is assured. The VAM splits the 3D elasticity problem into two parts: A 1D problem along the length of the cylinder which gives the twist and a 2D cross-sectional problem which gives the radial deformation. This enables closed form solutions, even for some complex problems. Starting with a hollow cylinder, made up of orthotropic but transversely isotropic material, the 3D problem has been formulated and solved analytically despite the presence of geometric nonlinearity. The general results have been specialized for particularly useful cases, such as solid cylinders and/or cylinders with isotropic material.

Asymptotic Approach to Oblique Cross-Sectional Analysis of Beams

2013 ◽  
Vol 81 (3) ◽  
Author(s):  
Anurag Rajagopal ◽  
Dewey H. Hodges
Keyword(s):  
Cross Section ◽  
Ad Hoc ◽  
Beam Theory ◽  
Reference Line ◽  
Cross Sectional ◽  
Cross Sectional Analysis ◽  
Variational Asymptotic ◽  
Validation Set ◽  
3D Elasticity ◽  
Sectional Analysis

Structural and aeroelastic analyses using beam theories by default choose a cross section that is perpendicular to the reference line. In several cases, such as swept wings with high AR, a beam theory that allows for the choice of a cross section that is oblique to the reference line may be more convenient. This work uses the variational asymptotic method (VAM) to develop such a beam theory. The problems addressed are the planar deformation of a strip and the full 3D deformation of a solid, prismatic, right-circular cylinder, both made of homogeneous, isotropic material. The motivation for choosing these problems is primarily the existence of 3D elasticity solutions, which comprise a complete validation set for all possible deformations and which are shown to be accurately captured by the current analysis. A secondary motivation was that the development and final results of the beam theory, i.e., the cross-sectional stiffness matrix and stress-strain-displacement recovery relations, are obtainable as closed-form analytical expressions. These results, coupled with the VAM-based beam analysis being devoid of ad hoc assumptions, culminate in what is expected to be of significance when formulating a general oblique cross-sectional analysis for beams with anisotropic material and initial curvature/twist, the detailed treatment of which will be alluded to in a later paper.

scholarly journals Prevalence of SARS-CoV-2 Infection at the University of Barcelona during the Third COVID-19 Pandemic Wave in Spain

2021 ◽  
Vol 18 (12) ◽  
pp. 6526
Author(s):  
Sebastián Videla ◽  
Aurema Otero ◽  
Sara Martí ◽  
M. Ángeles Domínguez ◽  
Nuria Fabrellas ◽  
...  
Keyword(s):  
Ad Hoc ◽  
Venous Blood ◽  
Herd Immunity ◽  
Cross Sectional Study ◽  
Rt Pcr ◽  
Igg Antibody ◽  
Cross Sectional ◽  
Total Prevalence ◽  
The University ◽  
The Impact

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic started in December 2019 and still is a major global health challenge. Lockdown measures and social distancing sparked a global shift towards online learning, which deeply impacted universities’ daily life, and the University of Barcelona (UB) was not an exception. Accordingly, we aimed to determine the impact of the SARS-CoV-2 pandemic at the UB. To that end, we performed a cross-sectional study on a sample of 2784 UB members (n = 52,529). Participants answered a brief, ad hoc, online epidemiological questionnaire and provided a nasal swab for reverse transcription polymerase chain reaction (RT-PCR) SARS-CoV-2 analysis and a venous blood sample for SARS-CoV-2 IgG antibody assay. Total prevalence of SARS-CoV-2 infection (positive RT-PCR or positive IgG) was 14.9% (95%CI 13.3 to 17.0%). Forty-four participants (1.6%, 95%CI: 1.2–2.1%) were positive for SARS-CoV-2 RT-PCR. IgG against SARS-CoV-2 was observed in 12.8% (95%CI: 11.6–14.1%) of participants. Overall, while waiting for population vaccination and/or increased herd immunity, we should concentrate on identifying and isolating new cases and their contacts.

scholarly journals How Does the Cause of Infantile Hemiparesis Influence Other Conditioning Factors? A Preliminary Study in a Spanish Population

Children ◽  
2021 ◽  
Vol 8 (5) ◽  
pp. 323
Author(s):  
Rocío Palomo-Carrión ◽  
Rita Pilar Romero-Galisteo ◽  
Helena Romay-Barrero ◽  
Inés Martínez-Galán ◽  
Cristina Lirio-Romero ◽  
...  
Keyword(s):  
Ad Hoc ◽  
Cross Sectional Study ◽  
Motor Dysfunction ◽  
Sensory Loss ◽  
Speech Impairments ◽  
Cross Sectional ◽  
Conditioning Factors ◽  
Age Of Diagnosis ◽  
The Mean ◽  
Preliminary Study

Infantile hemiparesis may be associated with significant morbidity and may have a profound impact on a child’s physical and social development. Infantile hemiparesis is associated with motor dysfunction as well as additional neurologic impairments, including sensory loss, mental retardation, epilepsy, and vision, hearing, or speech impairments. The objective of this study was to analyze the association between the cause of infantile hemiparesis and birth (gestational age), age of diagnosis, and associated disorders present in children with infantile hemiparesis aged 0 to 3 years. An observational and cross-sectional study was performed. A simple and anonymous questionnaire was created ad hoc for parents of children diagnosed with infantile hemiparesis aged between 0 and 3 years about the situation regarding the diagnosis of hemiparesis, birth, cause of hemiparesis, and presence of other associated disorders. Perinatal stroke (60.1%) was the most common cause of hemiparesis, and the most typical associated disorder was epilepsy (34.2%), with the second largest percentage in this dimension corresponding to an absence of associated disorders (20.7%). The most frequent birth was “no premature” (74.1%). The mean age of diagnosis of infantile hemiparesis was registered at 8 months (IQR: 0–36). Knowing the possible association between different conditioning factors and the cause of infantile hemiparesis facilitates the prevention of severe sequelae in children and family, implementing an early comprehensive therapeutic approach in children with infantile hemiparesis.

THE ANALYSIS OF DYNAMICAL RESPONSE OF TRANSVERSELY ISOTROPIC MATERIAL UNDER BLASTING LOAD

2008 ◽  
Vol 22 (09n11) ◽  
pp. 1443-1448
Author(s):  
YUE-XIU WU ◽  
QUAN-SHENG LIU
Keyword(s):  
Isotropic Material ◽  
Peak Velocity ◽  
Transversely Isotropic ◽  
Normal Direction ◽  
Dynamical Response ◽  
Transversely Isotropic Material ◽  
Peak Acceleration ◽  
Loading Direction ◽  
Blasting Load ◽  
Explosion Load

To understand the dynamic response of transversely isotropic material under explosion load, the analysis is done with the help of ABAQUS software and the constitutive equations of transversely isotropic material with different angle of isotropic section. The result is given: when the angle of isotropic section is settled, the velocity and acceleration of measure points decrease with the increasing distance from the explosion borehole. The velocity and acceleration in the loading direction are larger than those in the normal direction of the loading direction and their attenuation are much faster. When the angle of isotropic section is variable, the evolution curves of peak velocity and peak acceleration in the loading direction with the increasing angles are notching parabolic curves. They get their minimum values when the angle is equal to 45 degree. But the evolution curves of peak velocity and peak acceleration in the normal direction of the loading direction with the increasing angles are overhead parabolic curves. They get their maximum values when the angle is equal to 45 degree.

scholarly journals Could Emotional Intelligence Ability Predict Salary? A Cross-Sectional Study in a Multioccupational Sample

2021 ◽  
Vol 18 (3) ◽  
pp. 1322
Author(s):  
Martin Sanchez-Gomez ◽  
Edgar Breso ◽  
Gabriele Giorgi
Keyword(s):  
Emotional Intelligence ◽  
Interpersonal Relationships ◽  
Work Experience ◽  
Ad Hoc ◽  
Preliminary Evidence ◽  
Cross Sectional Study ◽  
Cross Sectional ◽  
Repair Capacity ◽  
Relevant Variable ◽  
Correlation And Regression Analysis

The study of emotional intelligence (EI) in work environments is a trending topic. However, few studies have examined the relationship between EI and salary. Therefore, the presented research aims to analyze the influence of EI on salary using a multioccupational sample. The participants were 785 subjects aged between 18 and 58 years (M = 39.41; SD = 10.95). EI ability was measured using the Mobile Emotional Intelligence Test (MEIT), while the salary was collected together with other sociodemographic variables in a questionnaire created ad hoc. After controlling for the age, gender, social class, educational level, and work experience variables, the results of correlation and regression analysis showed that participants with higher EI and emotional-repair capacity generally have higher salary. These findings provide preliminary evidence that EI is a relevant variable in achieving career success. The ability to channel and manage emotions could help employees develop stronger interpersonal relationships, leading to higher positions and greater financial compensation.

scholarly journals The Association between Dating Apps and Alcohol Consumption in an Italian Sample of Active Users, Former Users, and Non-Users

2021 ◽  
Vol 10 (7) ◽  
pp. 249
Author(s):  
Luca Flesia ◽  
Valentina Fietta ◽  
Carlo Foresta ◽  
Merylin Monaro
Keyword(s):  
Alcohol Consumption ◽  
Alcohol Use ◽  
Ad Hoc ◽  
Multiple Logistic Regression Analysis ◽  
Cross Sectional Study ◽  
Cross Sectional ◽  
Dating Apps ◽  
Regular Consumption ◽  
And Gender ◽  
The Relationship

To date, the relationship between alcohol use and dating app use has been investigated mostly in conjunction with sexual activities and in homosexual men. For this reason, the aim of this study was to explore the association between dating app use and alcohol consumption among the general population. A cross-sectional study was conducted including app users, non-users, and former users: 1278 respondents completed an online ad hoc questionnaire assessing dating app use, motivations for installing dating apps, alcohol use, and demographics. Multiple logistic regression analysis was run to investigate the association between dating app use, demographic features, and alcohol consumption. Whereas educational level, age, and gender significantly contributed to the regular consumption of alcohol, dating app use did not account for a significant amount of variance between regular and not regular drinkers. However, people who installed and used dating apps with the motivation of searching for sexual partners were more likely to be regular drinkers. Among the active users, heavy app users were less likely to drink regularly. The study indicates that underlying factors (sexual aspects, motives for using the apps) and the intensity of using the apps may mediate the relationship between dating app use and alcohol use.

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