scholarly journals Strategic Damping Placement in Viscoelastic Bandgap Structures: Dissecting the Metadamping Phenomenon in Multiresonator Metamaterials

2020 ◽  
Vol 88 (2) ◽  
Author(s):  
A. Aladwani ◽  
M. Nouh
Keyword(s):  
Wave Attenuation ◽  
Polymeric Composite ◽  
Cell Models ◽  
One Dimensional ◽  
Relaxation Parameters ◽  
Hereditary Theory ◽  
Host Structure ◽  
The Individual ◽  
Theory Of Viscoelasticity ◽  
Unique Ability

Abstract Energy dissipation in polymeric composite metamaterials requires special mathematical models owing to the viscoelastic nature of their constituents, namely, the polymeric matrix, bonding agent, and local resonators. Unlike traditional composites, viscoelastic metamaterials possess a unique ability to exhibit strong wave attenuation while retaining high stiffness as a result of the “metadamping” phenomenon attributed to local resonances. The objective of this work is to investigate viscoelastic metadamping in one-dimensional multibandgap metamaterials by combining the linear hereditary theory of viscoelasticity with the Floquet-Bloch theory of wave propagation in infinite elastic media. Important distinctions between metamaterial and phononic unit cell models are explained based on the free wave approach with wavenumber-eliminated damping-frequency band structures. The developed model enables viscoelastic metadamping to be investigated by varying two independent relaxation parameters describing the viscoelasticity level in the host structure and the integrated resonators. The dispersion mechanics within high damping regimes and the effects of boundary conditions on the damped response are detailed. The results reveal that in a multiresonator cell, strategic damping placement in the individual resonators plays a profound role in shaping intermediate dispersion branches and dictating the primary and secondary frequency regions of interest, within which attenuation is most required.

Perceived Mutual Understanding (PMU)

2019 ◽  
Vol 35 (1) ◽  
pp. 98-108 ◽  
Author(s):  
Michael J. Burtscher ◽  
Jeannette Oostlander
Keyword(s):  
Mutual Understanding ◽  
Team Cognition ◽  
Internal Reliability ◽  
Confirmatory Factor Analyses ◽  
Team Processes ◽  
One Dimensional ◽  
Item Parameters ◽  
Three Samples ◽  
Confirmatory Factor ◽  
The Individual

Abstract. Team cognition plays an important role in predicting team processes and outcomes. Thus far, research has focused on structured cognition while paying little attention to perceptual cognition. The lack of research on perceptual team cognition can be attributed to the absence of an appropriate measure. To address this gap, we introduce the construct of perceived mutual understanding (PMU) as a type of perceptual team cognition and describe the development of a respective measure – the PMU-scale. Based on three samples from different team settings ( NTotal = 566), our findings show that the scale has good psychometric properties – both at the individual as well as at the team-level. Item parameters were improved during a multistage process. Exploratory as well as confirmatory factor analyses indicate that PMU is a one-dimensional construct. The scale demonstrates sufficient internal reliability. Correlational analyses provide initial proof of construct validity. Finally, common indicators for inter-rater reliability and inter-rater agreement suggest that treating PMU as a team-level construct is justified. The PMU-scale represents a convenient and versatile measure that will potentially foster empirical research on perceptual team cognition and thereby contribute to the advancement of team cognition research in general.

An Analysis of Coupled Multicomponent Diffusion in Interstitial Tissue

1994 ◽  
Vol 116 (2) ◽  
pp. 164-171 ◽  
Author(s):  
P. D. Schreuders ◽  
K. R. Diller ◽  
J. J. Beaman ◽  
H. M. Paynter
Keyword(s):  
Multicomponent Diffusion ◽  
Frequency Parameter ◽  
Interstitial Tissue ◽  
Specific System ◽  
Species Concentration ◽  
One Dimensional ◽  
Jump Distance ◽  
Local Species ◽  
The Individual ◽  
Graph Form

A one-dimensional multicomponent kinetic model was developed to simulate the interstitial diffusion of macromolecules in a three component system, consisting of water, the macromolecule and the interstitial matrix. Movement of the individual components was modeled as occurring in finite jumps between discrete low energy wells along paths defined in terms of species occupation. The flow rate was expressed as a function of the local species concentration, the jump distance, and a kinetic frequency parameter. The model, implemented in pseudo-bond graph form, was examined by fitting it to data obtained for the transport of fluorescein tagged dextran to determine the kinetic constants for that specific system.

Performance Prediction for Automotive Turbocharger Compressors

1975 ◽  
Vol 189 (1) ◽  
pp. 557-565 ◽  
Author(s):  
A. Whitfield ◽  
F. J. Wallace
Keyword(s):  
Performance Prediction ◽  
Flow Analysis ◽  
Compressor Stage ◽  
Thermodynamic Models ◽  
Flow Rates ◽  
Design Point ◽  
One Dimensional ◽  
Dimensional Flow ◽  
Performance Map ◽  
The Individual

A procedure to predict the complete performance map of turbocharger centrifugal compressors is presented. This is based on a one-dimensional flow analysis using existing published loss correlations that were available and thermodynamic models to describe the incidence loss and slip factor variation at flow rates which differ from the design point. To predict the losses within the complete compressor stage using a one-dimensional flow procedure, it is necessary to introduce a number of empirical parameters. The uncertainty associated with these empirical parameters is assessed by studying the effect of varying them upon the individual losses and upon the overall predicted performance.

scholarly journals Time-resolved observation of spin-charge deconfinement in fermionic Hubbard chains

Science ◽  
2020 ◽  
Vol 367 (6474) ◽  
pp. 186-189 ◽  
Author(s):  
Jayadev Vijayan ◽  
Pimonpan Sompet ◽  
Guillaume Salomon ◽  
Joannis Koepsell ◽  
Sarah Hirthe ◽  
...  
Keyword(s):  
Degrees Of Freedom ◽  
Spatial Separation ◽  
Real Space ◽  
Quantum Gas ◽  
Interacting Particles ◽  
Time Resolved ◽  
One Dimensional ◽  
Quantum Numbers ◽  
Charge Correlations ◽  
The Individual

Elementary particles carry several quantum numbers, such as charge and spin. However, in an ensemble of strongly interacting particles, the emerging degrees of freedom can fundamentally differ from those of the individual constituents. For example, one-dimensional systems are described by independent quasiparticles carrying either spin (spinon) or charge (holon). Here, we report on the dynamical deconfinement of spin and charge excitations in real space after the removal of a particle in Fermi-Hubbard chains of ultracold atoms. Using space- and time-resolved quantum gas microscopy, we tracked the evolution of the excitations through their signatures in spin and charge correlations. By evaluating multipoint correlators, we quantified the spatial separation of the excitations in the context of fractionalization into single spinons and holons at finite temperatures.

Stage-specific changes in cytoplasmic protein synthesis in Entomophaga aulicae protoplasts

1989 ◽  
Vol 35 (3) ◽  
pp. 373-378
Author(s):  
Richard A. Nolan
Keyword(s):  
Protein Synthesis ◽  
Developmental Stages ◽  
Late Fusion ◽  
One Dimensional ◽  
Early Fusion ◽  
Specific Proteins ◽  
Fungal Protoplasts ◽  
General Protein ◽  
The Individual ◽  
Synthesis Stage

The patterns of protein synthesis associated with three sequential stages in protoplast morphogenesis (spindle-shaped, early fusion sphere, and late fusion sphere protoplasts) of the fungus Entomophaga aulicae were studied using both one-dimensional gels with general protein staining and two-dimensional gels with [35S]methionine protein labelling and fluorography. A total of 332 proteins were observed with 63.5% (211) common to all three developmental stages. Of the individual totals, 3.3% (8 out of 245), 7.3% (22 out of 301), and 4.5% (13 out of 286) of the proteins were unique to the spindle-shaped, early fusion sphere, and late fusion sphere protoplasts, respectively. The molecular mass and pI distribution profiles for early fusion sphere protoplast proteins are discussed.Key words: protein synthesis, stage-specific proteins, fungal protoplasts, Entomophaga aulicae.

scholarly journals Claims Reserving in Continuous Time; A Nonparametric Bayesian Approach

1996 ◽  
Vol 26 (2) ◽  
pp. 139-164 ◽  
Author(s):  
Svend Haastrup ◽  
Elja Arjas
Keyword(s):  
Bayesian Approach ◽  
Posterior Distribution ◽  
Continuous Time ◽  
Marked Point ◽  
Marked Point Process ◽  
Nonparametric Bayesian ◽  
Occurrence Time ◽  
One Dimensional ◽  
The Individual ◽  
Reporting Delay

AbstractOccurrences and developments of claims are modelled as a marked point process. The individual claim consists of an occurrence time, two covariates, a reporting delay, and a process describing partial payments and settlement of the claim. Under certain likelihood assumptions the distribution of the process is described by 14 one-dimensional components. The modelling is nonparametric Bayesian. The posterior distribution of the components and the posterior distribution of the outstanding IBNR and RBNS liabilities are found simultaneously. The method is applied to a portfolio of accident insurances.

The general Lie group and similarity solutions for the one-dimensional Vlasov–Maxwell equations

1985 ◽  
Vol 33 (2) ◽  
pp. 219-236 ◽  
Author(s):  
Dana Roberts
Keyword(s):  
Lie Group ◽  
Maxwell Equations ◽  
Transformation Group ◽  
Spatial Dimension ◽  
Similarity Solutions ◽  
One Dimensional ◽  
Special Cases ◽  
General Similarity ◽  
The One ◽  
The Individual

The general Lie point transformation group and the associated reduced differential equations and similarity forms for the solutions are derived here for the coupled (nonlinear) Vlasov–Maxwell equations in one spatial dimension. The case of one species in a background is shown to admit a larger group than the multi-species case. Previous exact solutions are shown to be special cases of the above solutions, and many of the new solutions are found to constrain the form of the distribution function much more than, for example, the BGK solutions do. The individual generators of the Lie group are used to find the possible subgroups. Finally, a simple physical argument is given to show that the asymptotic solution (t→∞) for a one-species, one-dimensional plasma is one of the general similarity solutions.

2-D AUTOMATIC COMPOSITION OF NODAL VALUES FROM NUMERICAL MODEL USING SCRIPT PROGRAMMING

2013 ◽  
Vol 62 (1) ◽  
Author(s):  
Rudi Heriansyah
Keyword(s):  
Finite Element ◽  
Numerical Modeling ◽  
Numerical Model ◽  
Finite Difference ◽  
Two Dimensional ◽  
Commercial Software ◽  
One Dimensional ◽  
Automatic Composition ◽  
The Individual ◽  
Individual Nodes

There are many commercial software to perform numerical modeling based on finite element (FEM) and finite difference (FDM) methods. It is often a requirement to the designer, that the values of the individual nodes in the numerical model are known. Usually, these softwares provide two methods to achieve this; firstly, by clicking directly onto the nodes of interest and secondly, by saving or exporting the whole nodal values to an external file. The former way is appropriate for models with small number of nodes, but as the number of nodes increases, it is no longer an efficient or effective way. Through the latter method, all nodal values are obtained, however the values are one-dimensional, and in some cases, only certain nodal values are required for presentation. In this paper, an algorithm for automatic composition of nodal values obtained from the second method mentioned above. The composed nodal values will be in two-dimensional form as this is the format used for uniform shaped model (square or rectangular). Since numerical softwares usually have facilities to save the data in a spreadsheet format, the proposed algorithm is implemented in this environment by using spreadsheet script programming.

scholarly journals Longitudinal wave propagation in a one-dimensional quasi-periodic waveguide

2019 ◽  
Vol 475 (2231) ◽  
pp. 20190392
Author(s):  
Vladislav S. Sorokin
Keyword(s):  
Wave Propagation ◽  
Wave Attenuation ◽  
Periodic Structures ◽  
Low Frequency ◽  
Periodic Waveguide ◽  
One Dimensional ◽  
Vibration Attenuation ◽  
Direct Separation ◽  
Longitudinal Wave Propagation ◽  
Spatial Modulations

The paper deals with the analysis of wave propagation in a general one-dimensional (1D) non-uniform waveguide featuring multiple modulations of parameters with different, arbitrarily related, spatial periods. The considered quasi-periodic waveguide, in particular, can be viewed as a model of pure periodic structures with imperfections. Effects of such imperfections on the waveguide frequency bandgaps are revealed and described by means of the method of varying amplitudes and the method of direct separation of motions. It is shown that imperfections cannot considerably degrade wave attenuation properties of 1D periodic structures, e.g. reduce widths of their frequency bandgaps. Attenuation levels and frequency bandgaps featured by the quasi-periodic waveguide are studied without imposing any restrictions on the periods of the modulations, e.g. for their ratio to be rational. For the waveguide featuring relatively small modulations with periods that are not close to each other, each of the frequency bandgaps, to the leading order of smallness, is controlled only by one of the modulations. It is shown that introducing additional spatial modulations to a pure periodic structure can enhance its wave attenuation properties, e.g. a relatively low-frequency bandgap can be induced providing vibration attenuation in frequency ranges where damping is less effective.

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