scholarly journals Extremely Non-Auxetic Behavior of a Typical Auxetic Microstructure Due to Its Material Properties

Materials ◽  
2021 ◽  
Vol 14 (24) ◽  
pp. 7837
Author(s):  
Mikołaj Bilski ◽  
Krzysztof W. Wojciechowski ◽  
Tomasz Stręk ◽  
Przemysław Kędziora ◽  
James N. Grima-Cornish ◽  
...  
Keyword(s):  
Symmetry Axis ◽  
Common Belief ◽  
Two Dimensional ◽  
Upper Limit ◽  
The Monte Carlo Method ◽  
Isotropic Media ◽  
Thermodynamic Conditions ◽  
The Common ◽  
Auxetic Structure ◽  
The Ideal

The re-entrant honeycomb microstructure is one of the most famous, typical examples of an auxetic structure. The re-entrant geometries also include other members as, among others, the star re-entrant geometries with various symmetries. In this paper, we focus on one of them, having a 6-fold symmetry axis. The investigated systems consist of binary hard discs (two-dimensional particles with two slightly different sizes, interacting through infinitely repulsive pairwise potential), from which different structures, based on the mentioned geometry, were formed. To study the elastic properties of the systems, computer simulations using the Monte Carlo method in isobaric-isothermal ensemble with varying shape of the periodic box were performed. The results show that all the considered systems are isotropic and not auxetic—their Poisson’s ratio is positive in each case. Moreover, Poisson’s ratios of the majority of examined structures tend to +1 with increasing pressure, which is the upper limit for two-dimensional isotropic media, thus they can be recognized as the ideal non-auxetics in appropriate thermodynamic conditions. The results obtained contradict the common belief that the unique properties of metamaterials result solely from their microstructure and indicate that the material itself can be crucial.

scholarly journals Extreme Poisson’s Ratios of Honeycomb, Re-Entrant, and Zig-Zag Crystals of Binary Hard Discs

Symmetry ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1127
Author(s):  
Mikołaj Bilski ◽  
Paweł M. Pigłowski ◽  
Krzysztof W. Wojciechowski
Keyword(s):  
High Pressures ◽  
Symmetry Axis ◽  
Analytic Formula ◽  
2D Systems ◽  
Two Dimensional ◽  
A Value ◽  
Upper Limit ◽  
The Monte Carlo Method ◽  
Isotropic Pressure ◽  
Different Diameters

Two-dimensional (2D) crystalline structures based on a honeycomb geometry are analyzed by computer simulations using the Monte Carlo method in the isobaric-isothermal ensemble. The considered crystals are formed by hard discs (HD) of two different diameters which are very close to each other. In contrast to equidiameter HD, which crystallize into a homogeneous solid which is elastically isotropic due to its six-fold symmetry axis, the systems studied in this work contain artificial patterns and can be either isotropic or anisotropic. It turns out that the symmetry of the patterns obtained by the appropriate arrangement of two types of discs strongly influences their elastic properties. The Poisson’s ratio (PR) of each of the considered structures was studied in two aspects: (a) its dependence on the external isotropic pressure and (b) in the function of the direction angle, in which the deformation of the system takes place, since some of the structures are anisotropic. In order to accomplish the latter, the general analytic formula for the orientational dependence of PR in 2D systems was used. The PR analysis at extremely high pressures has shown that for the vast majority of the considered structures it is approximately direction independent (isotropic) and tends to the upper limit for isotropic 2D systems, which is equal to +1. This is in contrast to systems of equidiameter discs for which it tends to 0.13, i.e., a value almost eight times smaller.

Aristotle on the Sources of the Ethical Life

2019 ◽  
Author(s):  
Sylvia Berryman
Keyword(s):  
Virtue Ethics ◽  
Human Nature ◽  
Common Belief ◽  
Ethical Life ◽  
Metaphysical Grounding ◽  
Middle Way ◽  
The Common

This work challenges the common belief that Aristotle’s virtue ethics is founded on an appeal to human nature, an appeal that is thought to be intended to provide both substantive ethical advice and justification for the demands of ethics. It is argued that it is not Aristotle’s intent, but the view is resisted that Aristotle was blind to questions of the source or justification of his ethical views. Aristotle’s views are interpreted as a ‘middle way’ between the metaphysical grounding offered by Platonists and the scepticism or subjectivist alternatives articulated by others. The commitments implicit in the nature of action figure prominently in this account: Aristotle reinterprets Socrates’ famous paradox that no one does evil willingly, taking it to mean that a commitment to pursuing the good is implicit in the very nature of action. This approach is compared to constructivism in contemporary ethics.

Introduction

2017 ◽  
Author(s):  
Erika Fischer-Lichte
Keyword(s):  
Middle Class ◽  
Social Group ◽  
Family Values ◽  
Court Culture ◽  
Common Root ◽  
New Family ◽  
The Common ◽  
German Court ◽  
The Ideal

The introduction ‘Philhellenism and Theatromania’ retraces the emergence of these two phenomena in the German middle class. The year 1755 marks a watershed in this regard: it saw the publication of J. J. Winckelmann’s treatise Reflections on the Painting and Sculpture of the Greeks and the premiere of G. E. Lessing’s first domestic tragedy Miß Sara Sampson. Both share the common root and motivation once and for all to banish Frenchified German court culture. While Winckelmann’s treatise praised the ‘noble simplicity’ and ‘quiet greatness’ of the Greek masterpieces, Lessing’s play advocated new family values and the ideal of ‘naturalness’ as the true virtues of the middle class. The merging of Philhellenism as the cult of beauty with theatromania as the quest for identifying in a social group and as an individual provided the basic condition for staging Greek tragedies.

scholarly journals From Norms to Facts: The Realization of Rights in Common and Civil Private Law

2011 ◽  
Vol 56 (1) ◽  
pp. 77-114 ◽  
Author(s):  
Helge Dedek
Keyword(s):  
Legal System ◽  
Deep Structure ◽  
Common Law ◽  
Social Reality ◽  
Judicial Decision Making ◽  
Legal Traditions ◽  
The United Kingdom ◽  
The Common ◽  
Legal Concepts ◽  
The Ideal

Every legal system that ties judicial decision making to a body of preconceived norms has to face the tension between the normative formulation of the ideal and its approximation in social reality. In the parlance of the common law, it is, more concretely, the remedy that bridges the gap between the ideal and the real, or, rather, between norms and facts. In the common law world—particularly in the United Kingdom and the Commonwealth—a lively discourse has developed around the question of how rights relate to remedies. To the civilian legal scholar—used to thinking within a framework that strictly categorizes terms like substance and procedure, subjective right, action, and execution—the concept of remedy remains a mystery. The lack of “remedy” in the vocabulary of the civil law is more than just a matter of attaching different labels to functional equivalents, it is the expression of a different way of thinking about law. Only if a legal system is capable of satisfactorily transposing the abstract discourse of the law into social reality does the legal machinery fulfill its purpose: due to the pivotal importance of this translational process, the way it is cast in legal concepts thus allows for an insight into the deep structure of a legal culture, and, convergence notwithstanding, the remaining epistemological differences between the legal traditions of the West. A mixed jurisdiction must reflect upon these differences in order to understand its own condition and to define its future course.

scholarly journals Two-Dimensional Materials with Giant Optical Nonlinearities near the Theoretical Upper Limit

ACS Nano ◽  
2021 ◽  
Vol 15 (4) ◽  
pp. 7155-7167
Author(s):  
Alireza Taghizadeh ◽  
Kristian S. Thygesen ◽  
Thomas G. Pedersen
Keyword(s):  
Optical Nonlinearities ◽  
Two Dimensional ◽  
Upper Limit ◽  
Two Dimensional Materials

scholarly journals Understanding Urban Commercial Vehicle Driver Behaviors and Decision Making

2021 ◽  
pp. 036119812110035
Author(s):  
Giacomo Dalla Chiara ◽  
Klaas Fiete Krutein ◽  
Andisheh Ranjbari ◽  
Anne Goodchild
Keyword(s):  
Commercial Vehicle ◽  
Operating Time ◽  
Common Belief ◽  
Policy Makers ◽  
Factors Affecting ◽  
Urban Freight ◽  
The Road ◽  
Commercial Drivers ◽  
The Common ◽  
Printed Materials

As e-commerce and urban deliveries spike, cities grapple with managing urban freight more actively. To manage urban deliveries effectively, city planners and policy makers need to better understand driver behaviors and the challenges they experience in making deliveries. In this study, we collected data on commercial vehicle (CV) driver behaviors by performing ridealongs with various logistics carriers. Ridealongs were performed in Seattle, Washington, covering a range of vehicles (cars, vans, and trucks), goods (parcels, mail, beverages, and printed materials), and customer types (residential, office, large and small retail). Observers collected qualitative observations and quantitative data on trip and dwell times, while also tracking vehicles with global positioning system devices. The results showed that, on average, urban CVs spent 80% of their daily operating time parked. The study also found that, unlike the common belief, drivers (especially those operating heavier vehicles) parked in authorized parking locations, with only less than 5% of stops occurring in the travel lane. Dwell times associated with authorized parking locations were significantly longer than those of other parking locations, and mail and heavy goods deliveries generally had longer dwell times. We also identified three main criteria CV drivers used for choosing a parking location: avoiding unsafe maneuvers, minimizing conflicts with other users of the road, and competition with other commercial drivers. The results provide estimates for trip times, dwell times, and parking choice types, as well as insights into why those decisions are made and the factors affecting driver choices.

Modulating 2D Heterointerface with g-C3N4 Meshes: A Suitable Hetero-Layered Architecture for High-Power and Long-Life Energy Storage

2021 ◽  
Author(s):  
Yunping Wu ◽  
Wei Wei ◽  
Tianyi Ding ◽  
Sheng Chen ◽  
Rui Zhai ◽  
...  
Keyword(s):  
Energy Storage ◽  
High Power ◽  
2D Materials ◽  
Two Dimensional ◽  
Energy Storage Devices ◽  
Storage Devices ◽  
Efficient Energy ◽  
Layered Architecture ◽  
The Common ◽  
Long Life

Two-dimensional (2D) heterostructures combine the advantageous features of different 2D materials and represent advanced electrode architectures for development of efficient energy storage devices. However, the common 2D heterostructures made by...

scholarly journals Chimera Spectrum Diagnostics for Peptides Using Two-Dimensional Partial Covariance Mass Spectrometry

Molecules ◽  
2021 ◽  
Vol 26 (12) ◽  
pp. 3728
Author(s):  
Taran Driver ◽  
Nikhil Bachhawat ◽  
Leszek J. Frasinski ◽  
Jonathan P. Marangos ◽  
Vitali Averbukh ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Peptide Sequence ◽  
Two Dimensional ◽  
Peptide Ions ◽  
Finite Mass ◽  
Protein Database ◽  
Spectra Analysis ◽  
Fragment Ions ◽  
Single Precursor ◽  
The Common

The rate of successful identification of peptide sequences by tandem mass spectrometry (MS/MS) is adversely affected by the common occurrence of co-isolation and co-fragmentation of two or more isobaric or isomeric parent ions. This results in so-called `chimera spectra’, which feature peaks of the fragment ions from more than a single precursor ion. The totality of the fragment ion peaks in chimera spectra cannot be assigned to a single peptide sequence, which contradicts a fundamental assumption of the standard automated MS/MS spectra analysis tools, such as protein database search engines. This calls for a diagnostic method able to identify chimera spectra to single out the cases where this assumption is not valid. Here, we demonstrate that, within the recently developed two-dimensional partial covariance mass spectrometry (2D-PC-MS), it is possible to reliably identify chimera spectra directly from the two-dimensional fragment ion spectrum, irrespective of whether the co-isolated peptide ions are isobaric up to a finite mass accuracy or isomeric. We introduce ‘3-57 chimera tag’ technique for chimera spectrum diagnostics based on 2D-PC-MS and perform numerical simulations to examine its efficiency. We experimentally demonstrate the detection of a mixture of two isomeric parent ions, even under conditions when one isomeric peptide is at one five-hundredth of the molar concentration of the second isomer.

scholarly journals Composite hollow truss with multiple vierendeel panels

2013 ◽  
Vol 66 (4) ◽  
pp. 431-438
Author(s):  
Augusto Ottoni Bueno da Silva ◽  
Newton de Oliveira Pinto Júnior ◽  
João Alberto Venegas Requena
Keyword(s):  
Bearing Capacity ◽  
Failure Modes ◽  
Three Dimensional ◽  
Analytical Calculation ◽  
Two Dimensional ◽  
Shear Forces ◽  
Vertical Displacements ◽  
New System ◽  
The Ideal

The aim of this study was to evaluate through analytical calculation, two-dimensional elastic modeling, and three-dimensional plastic modeling, the bearing capacity and failure modes of composite hollow trusses bi-supported with a 15 meter span, varying the number of central Vierendeel panels. The study found the proportion span/3 - span/3 - span/3, as the ideal relationship for the truss - Vierendeel - truss lengths, because by increasing the proportion of the length occupied by the central Vierendeel panels, the new system loses stiffness and no longer supports the load stipulated in the project. Furthermore, they can start presenting excessive vertical displacements and insufficient resistance to external shear forces acting on the panels.

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