Effect of longitudinal deformation on wave propagation in truss core sandwich panel

2020 ◽  
pp. 095745652096488
Author(s):  
Sun Liang ◽  
Xiao Yougang
Keyword(s):  
Transverse Direction ◽  
Sandwich Panel ◽  
Sandwich Panels ◽  
Theoretical Models ◽  
The Other ◽  
Full Model ◽  
Longitudinal Deformation ◽  
Compressive Wave ◽  
High Frequencies ◽  
Truss Core

The longitudinal deformation has been ignored by most previous study on vibroacoustic behaviours of truss core sandwich panels. This paper investigates its effect by developing two theoretical models. One, named as full model, considers both flexural and longitudinal deformation of face sheets while the other, named as flexural model, incorporates only flexural deformation. By comparing free characteristic waves obtained from two models, one find that flexural model ignore two waves, that is, a compressive wave and a global flexural one. The ignored waves cause vibration in transverse direction even at high frequencies, and thus result in vibration peaks under forced vibration. Therefore the flexural model would underestimate the vibration response, and the longitudinal deformation of face sheets cannot be ignored during dynamic analysis of the sandwich panels.

The Problem of the Typology of Rationality in Muslim Culture

2019 ◽  
Vol 62 (6) ◽  
pp. 88-99
Author(s):  
Andrey A. Lukashev
Keyword(s):  
Modern Philosophy ◽  
Theoretical Basis ◽  
Theoretical Models ◽  
The Other ◽  
Common Denominator ◽  
Islamic Culture ◽  
The Common ◽  
Per Se ◽  
The One ◽  
Muslim Culture

The typology of rationality is one of major issues of modern philosophy. In an attempt to provide a typology to Oriental materials, a researcher faces additional problems. The diversity of the Orient as such poses a major challenge. When we say “Oriental,” we mean several cultures for which we cannot find a common denominator. The concept of “Orient” involves Arabic, Indian, Chinese, Turkish and other cultures, and the only thing they share is that they are “non-Western.” Moreover, even if we focus just on Islamic culture and look into rationality in this context, we have to deal with a conglomerate of various trends, which does not let us define, with full confidence, a common theoretical basis and treat them as a unity. Nevertheless, we have to go on trying to find common directions in thought development, so as to draw conclusions about types of rationality possible in Islamic culture. A basis for such a typology of rationality in the context of the Islamic world was recently suggested in A.V. Smirnov’s logic of sense theory. However, actual empiric material cannot always fit theoretical models, and the cases that do not fit the common scheme are interesting per se. On the one hand, examination of such cases gives an opportunity to specify certain provisions of the theory and, on the other hand, to define the limits of its applicability.

scholarly journals A numerical study of the impact perforation of sandwich panels with graded hollow sphere cores

2021 ◽  
Vol 13 (4) ◽  
pp. 168781402110094
Author(s):  
Ibrahim Elnasri ◽  
Han Zhao
Keyword(s):  
Boundary Conditions ◽  
Hollow Sphere ◽  
Sandwich Panel ◽  
Numerical Study ◽  
Sandwich Panels ◽  
Hopkinson Bar ◽  
Core Density ◽  
The Core ◽  
The Impact ◽  
Force Displacement

In this study, we numerically investigate the impact perforation of sandwich panels made of 0.8 mm 2024-T3 aluminum alloy skin sheets and graded polymeric hollow sphere cores with four different gradient profiles. A suitable numerical model was conducted using the LS-DYNA code, calibrated with an inverse perforation test, instrumented with a Hopkinson bar, and validated using experimental data from the literature. Moreover, the effects of quasi-static loading, landing rates, and boundary conditions on the perforation resistance of the studied graded core sandwich panels were discussed. The simulation results showed that the piercing force–displacement response of the graded core sandwich panels is affected by the core density gradient profiles. Besides, the energy absorption capability can be effectively enhanced by modifying the arrangement of the core layers with unclumping boundary conditions in the graded core sandwich panel, which is rather too hard to achieve with clumping boundary conditions.

Mechanical and thermal insulate behaviors of pultruded GFRP truss-core sandwich panels filled with EPS mortar

2021 ◽  
Vol 21 (2) ◽  
Author(s):  
Sensen Li ◽  
Bei Zhang ◽  
Dapeng Yang ◽  
He Wang ◽  
Yang Liu ◽  
...  
Keyword(s):  
Sandwich Panels ◽  
Truss Core

PROBING AWAY SIDE JET MODIFICATION WITH THREE PARTICLE CORRELATIONS

2007 ◽  
Vol 16 (07n08) ◽  
pp. 1982-1987
Author(s):  
◽  
N. N. AJITANAND
Keyword(s):  
Spatial Distribution ◽  
Correlation Functions ◽  
Theoretical Models ◽  
The Other ◽  
Experimental Investigations ◽  
Powerful Method ◽  
Particle Correlation ◽  
Low Viscosity ◽  
Jet Modification ◽  
Rhic Data

Recent experimental investigations have focussed on the abnormal spatial distribution of away side jet fragments as signals of significant medium induced effects. A variety of theoretical models including recent string-theory based efforts have supported the notion of Mach Cone like effects in the low viscosity QGP fluid. However, the presence of significant flow fields may deflect the fragmentation direction producing a significantly differing type of jet topology from that of the Mach cone. Three particle correlation functions constitute a powerful method whereby the predominance of one or the other type of mechanism can be differentiated. In this work the use of such an approach will be demonstrated via simulations and the results of its application to RHIC data will be presented.

Prediction of Sound Transmission Loss for Finite Sandwich Panels Based on a Test Procedure on Beam Elements

2013 ◽  
Vol 135 (6) ◽  
Author(s):  
Zhongchang Qian ◽  
Daoqing Chang ◽  
Bilong Liu ◽  
Ke Liu
Keyword(s):  
Sandwich Panel ◽  
Transmission Loss ◽  
Test Procedure ◽  
Sandwich Panels ◽  
Sound Transmission ◽  
Expansion Method ◽  
Bending Stiffness ◽  
Sound Transmission Loss ◽  
Modal Expansion ◽  
Beam Elements

An approach on the prediction of sound transmission loss for a finite sandwich panel with honeycomb core is described in the paper. The sandwich panel is treated as orthotropic and the apparent bending stiffness in two principal directions is estimated by means of simple tests on beam elements cut from the sandwich panel. Utilizing orthotropic panel theory, together with the obtained bending stiffness in two directions, the sound transmission loss of simply-supported sandwich panel is predicted by the modal expansion method. Simulation results indicated that dimension, orthotropy, and loss factor may play important roles on sound transmission loss of sandwich panel. The predicted transmission loss is compared with measured data and the agreement is reasonable. This approach may provide an efficient tool to predict the sound transmission loss of finite sandwich panels.

scholarly journals Breach of Contact: An Intercultural Reading of China Miéville's 'The City and The City'

2014 ◽  
Vol 11 (2) ◽  
Author(s):  
Barbara Elizabeth Hanna ◽  
Peter Cowley
Keyword(s):  
Theoretical Models ◽  
The Other ◽  
Intercultural Training ◽  
The Novel ◽  
Intercultural Encounters ◽  
Training Courses ◽  
City States ◽  
City Relations ◽  
The City ◽  
Two Populations

China Miéville’s 2009 'Weird' detective novel The City and The City is a tale of two city states, culturally distinct, between which unpoliced contact is forbidden. While residents of each city can learn about the other’s history, geography, politics, see photographs and watch news footage of the other city, relations between the two are tightly monitored and any direct contact requires a series of protocols, some of which might seem reasonable, or at least familiar: entry permits, international mail, international dialing codes, intercultural training courses. What complicates these apparently banal measures is the relative positioning of the two cities, each one around, within, amongst the other. The two populations live side by side, under a regime which requires ostentatious and systematic disregard or 'unnoticing' of the other in any context but a tightly regulated set of encounters. For all that interculturality is endemic to everyday life in the 21st century, what is striking is that critical and popular uptake of this novel so frequently decries the undesirability, the immorality even, of the cultural separation between the two populations, framing it as an allegory of unjust division within a single culture, and thus by implication endorsing the erasure of intercultural difference. We propose an alternative reading which sees this novel as exploring the management of intercultural encounters, and staging the irreducibility of intercultural difference. We examine how the intercultural is established in the novel, and ask how it compares to its representations in prevalent theoretical models, specifically that of the Third Place.

scholarly journals PAKARTOJIMAS IR NIHILIZMAS

Problemos ◽  
2013 ◽  
Vol 84 ◽  
pp. 46-59
Author(s):  
Rita Šerpytytė
Keyword(s):  
Theoretical Models ◽  
The Other ◽  
Philosophical Tradition ◽  
Western Tradition ◽  
Other Hand ◽  
Text Fragment ◽  
Western Philosophical Tradition ◽  
Universal Structure ◽  
The One

Straipsnio tikslas yra atskleisti Vakarų filosofijos tradicijoje savitai įsitvirtinusios patyrimo struktūros, įvardijamos pakartojimu, nihilistinę prasmę. Šioje hermeneutinėje analizėje, viena vertus, re­miamasi tam tikra nihilizmo samprata, numatančia du nihilizmo teorinius modelius – nihilizmą, parem­tą Überwindung teorija, ir nihilizmą, paremtą différance idėja. Kita vertus, remiamasi tam tikru („onto-teologiniu“) pretekstu Vakarų mąstymo tradicijoje atpažįstant pakartojimo struktūrą – Pauliaus Laiško efeziečiams Ef. I, 10 teksto fragmentu, laikomu paradigmine pakartojimo struktūros išsklaida. Herme­neutinė analizė projektuojama į Kierkegaardo ir Agambeno filosofiją, atskirus jų mąstyme atpažįstamus pakartojimo invariantus atskleidžiant kaip minėto Pauliaus Laiško fragmento eksplozijos atvejus. Ke­liamas klausimas, kas yra pakartojimas, kur slypi jo negatyvumas ir kaip pasirodo jo nihilistinė prasmė? Kaip šioje negatyvumo ir nihilizmo atskleistyje „tarpininkauja“ différance? Straipsnyje parodoma, jog skirtis kaip neigimo judesys, atstovaujantis nihilistinei logikai, gali būti traktuojamas ir vien formaliai, ir realiai. Skirties kaip realaus neigimo traktavimas Kierkegaardo ir Agambeno mąstyme atitinka pačios patirties struktūros – pakartojimo – ontologinį (tikrovišką) įšaknytumą.Pagrindiniai žodžiai: pakartojimas, nihilizmas, différance, negatyvumas, laikasPakartojimas ir nihilizmasRita Šerpytytė   AbstractThe purpose of this article is to reveal the nihilistic sense of an experiential structure, which has been distinctively rooted in Western philosophical tradition. On the one hand, this hermeneutical analysis will be based on a certain conception of nihilism presupposing two theoretical models of nihilism – nihilism, which refers to the theory of Überwindung, and nihilism associated with the idea of différance. On the other hand, it builds upon a certain (the so-called “onto-theological”) pretext, which might be used for recognition of the structure of repetition in Western tradition of thinking, – i.e. the fragment of a text from St. Paul’s Letter to the Ephesians Eph. I, 10 – the paradigmatic passage proposing this universal structure of repetition. Focused both on philosophy of Kierkegaard and Agamben, hermeneutical analysis will aim to disclose the separate invariants of such repetition as cases of explosion of the mentioned text fragment. The question is raised – what is repetition? Where does its negativity lie? How does its nihilistic sense appear? How does the différance mediate in this process of revealing of negativity and nihilism? The article argues that difference, as a motion of negation representing nihilistic logic, can be treated both in merely formal and in a realistic way. The treating of différance as real denying in Kierkegaard’s and Agamben’s thinking corresponds to the ontological rootedness of the very structure of experience – repetition.Keywords: repetition, nihilism, différance, negativity, time

scholarly journals A model-based method for detecting persistent cultural change using panel data

2020 ◽  
Author(s):  
Stephen Vaisey ◽  
Kevin Kiley
Keyword(s):  
Panel Data ◽  
Cultural Change ◽  
Structural Equation ◽  
Cultural Beliefs ◽  
Local Environment ◽  
Theoretical Models ◽  
The Other ◽  
Equation Modeling ◽  
Survey Responses ◽  
Close Fit

Kiley and Vaisey (2020) recently published a method for assessing whether survey respondents appear to be changing their beliefs between waves or whether they instead appear to be repeating fixed responses with temporary local influences. This question is important because these processes reflect very different theoretical models of the evolution of “personal culture.” That is, if cultural beliefs are primarily public and responsive to external discourse, we should observe more updating as people respond to changes in their local environment. On the other hand, if cultural beliefs are primarily something learned early, then “settled dispositions” should be relatively resilient to change. In this paper, we build on Kiley and Vaisey (2020) and introduce an alternative method for distinguishing between cases where respondents appear be actively updating their responses and situations where respondents’ responses appear to be settled. This method, based on structural equation modeling, provides a close fit to the theoretical models outlined in Kiley and Vaisey (2020) and provides even stronger support for their claim that most survey responses reflect settled dispositions developed prior to adulthood.

A vibration-based identification of elastic properties of stitched sandwich panels

2018 ◽  
Vol 53 (5) ◽  
pp. 579-592 ◽  
Author(s):  
Nan Li ◽  
Mabrouk Ben Tahar ◽  
Zoheir Aboura ◽  
Kamel Khellil
Keyword(s):  
Elastic Properties ◽  
Transverse Direction ◽  
Sandwich Panel ◽  
Low Cost ◽  
Element Model ◽  
Vibration Test ◽  
Structural Application ◽  
Sensibility Analysis ◽  
The Cost ◽  
Non Destructive

Stitched sandwich becomes popular in structural application owing to its better performance in the transverse direction with respect to classical sandwich structure and relatively low-cost additional stitching process. The identification of its elastic properties is essential for offering a tailored structure for specific applications. A non-destructive identification method based on vibration test is proposed to obtain these parameters. The number of parameters is firstly reduced by a sensibility analysis. The retained parameters are identified by minimizing the cost function which indicates the gap between measured frequencies from vibration test and calculated frequencies from a finite element model. This method is applied to a stitched sandwich panel and its elastic properties are successfully identified.

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