Symmetry Model Research Articles

Detection of grey zones in inter-rater agreement studies

BackgroundIn inter-rater agreement studies, the assessment behaviour of raters can be influenced by their experience, training levels, the degree of willingness to take risks, and the availability of clear guidelines for the assessment. When the assessment behaviour of raters differentiates for some levels of an ordinal classification, a grey zone occurs between the corresponding adjacent cells to these levels around the main diagonal of the table. A grey zone introduces a negative bias to the estimate of the agreement level between the raters. In that sense, it is crucial to detect the existence of a grey zone in an agreement table.MethodsIn this study, a framework composed of a metric and the corresponding threshold is developed to identify grey zones in an agreement table. The symmetry model and Cohen’s kappa are used to define the metric, and the threshold is based on a nonlinear regression model. A numerical study is conducted to assess the accuracy of the developed framework. Real data examples are provided to illustrate the use of the metric and the impact of identifying a grey zone.ResultsThe sensitivity and specificity of the proposed framework are shown to be very high under moderate, substantial, and near-perfect agreement levels for 3times 3 and 4 times 4 tables and sample sizes greater than or equal to 100 and 50, respectively. Real data examples demonstrate that when a grey zone is detected in the table, it is possible to report a notably higher level of agreement in the studies.ConclusionsThe accuracy of the proposed framework is sufficiently high; hence, it provides practitioners with a precise way to detect the grey zones in agreement tables.

A Novel Feature Descriptor for Hyperbola Recognition in GPR Images Based on Symmetry Model

A Novel Feature Descriptor for Hyperbola Recognition in GPR Images Based on Symmetry Model

The need for operando modelling of 27Al NMR in zeolites: the effect of temperature, topology and water.

Solid state (ss-) 27Al NMR is one of the most valuable tools for the experimental characterization of zeolites, owing to its high sensitivity and the detailed structural information which can be extracted from the spectra. Unfortunately, the interpretation of ss-NMR is complex and the determination of aluminum distributions remains generally unfeasible. As a result, computational modelling of 27Al ss-NMR spectra has grown increasingly popular as a means to support experimental characterization. However, a number of simplifying assumptions are commonly made in NMR modelling, several of which are not fully justified. In this work, we systematically evaluate the effects of various common models on the prediction of 27Al NMR chemical shifts in zeolites CHA and MOR. We demonstrate the necessity of operando modelling; in particular, taking into account the effects of water loading, temperature and the character of the charge-compensating cation. We observe that conclusions drawn from simple, high symmetry model systems such as CHA do not transfer well to more complex zeolites and can lead to qualitatively wrong interpretations of peak positions, Al assignment and even the number of signals. We use machine learning regression to develop a simple yet robust relationship between chemical shift and local structural parameters in Al-zeolites. This work highlights the need for sophisticated models and high-quality sampling in the field of NMR modelling and provides correlations which allow for the accurate prediction of chemical shifts from dynamical simulations.

Refractive symmetry analysis of fellow eyes

The biological structure of human body frequently exhibit symmetry. The hypothesis of refractive symmetry assumes that the two eyes of an individual should have homogeneous refractive properties. Optometry clinical management mostly rely upon meridional magnification effect, spatial distortion, and binocular spatial perception while prescribing refractive correction. Additionally, bilateral symmetry analysis approach has proven very informative for better diagnosis. This study was multi-centered, cross-sectional, analytical, and retrospective, where we studied refractive errors with conventional clinical notation using the sphere, cylinder, and axis. The collected data were scrutinized using the SPSS, Minitab Statistical Software. In inter-ocular symmetry analysis, if the numerical difference between both axes is zero, Equal Octant or Direct Symmetry is to be considered. While, with Mirror Octants or Mirror Symmetry or Enantiomorphism, the axes difference is not zero, but the portrayal of the figures are reverberatory. 53.23% and 70.15% of the cases rooted in the Equal Octant and Mirror Octant pattern respectively, within 15° of absolute symmetry. Analysis showed that age between 7 to 14 years has the lowest inter-ocular axis difference with both the models. The average difference in inter-ocular axis was significantly reduced in the isorule group compared to the anisorule group, as observed in both direct and mirror symmetry models. Interval plot shows a lower interval proximity for Mirror Octant, in compare to Equal Octant. We tracked down that isorule bilateral astigmatism dominates the study population. Whereas, Mirror Octant is more periodic than Equal Octant.

Fermion mass formulation in the Modified Left-Right Symmetry Model

The Modified Left Right Symmetry Model is an extension of the Standard Model. This model introduces left-handed neutrinos to the right sector and a doublet scalar field to the left sector. This model cannot yet explain the mass generation of fermions and neutrinos. This study is theoretical research using the literature review method. Generating the masses of fermions (quark up-down) and electrons through spontaneous symmetry breaking in Yukawa's Lagrangian term produces a particle mass in the left sector, the same as the calculations in the Standard Model. The masses of fermions (up-down quarks) and electrons for the right sector produced in this study are much more massive than those of fermions (up-down quarks) and the left sector. The neutrino masses produced in this study are by following the Seesaw Mechanism. That is, if one neutrino mass is massive, then the other neutrino masses will be light.©2022 JNSMR UIN Walisongo. All rights reserved.

Symmetry and Symmetry Breaking in Science and Arts

In this review article, symmetry and symmetry breaking are considered as complementary principles in science and arts. It starts with symmetry and symmetry breaking in early world views of nature and art. Then, symmetries are definied as fundamental structures of mathematics. Mathematical models of symmetry and symmetry breaking are used to explain the emergence of space-time and matter in modern physics. Even molecular structures in chemistry are distinguished by mathematical symmetries. Their elegance and beauty seem to realize aesthetical categories in nature. In biological evolution, the question arises how symmetry breaking (e.g. molcular chirality) can be explained. In modern arts, symmetry and symmetry breaking are „hidden“ structures which can be found in music, painting, and architecture. In a philosophical outlook, symmetry and symmetry breaking are highlighted as regulative guiding ideas of research.

Symmetry and symmetry breaking in science and arts

In this review article, symmetry and symmetry breaking are considered as complementary principles in science and arts. It starts with symmetry and symmetry breaking in early world views of nature and art. Then, symmetries are definied as fundamental structures of mathematics. Mathematical models of symmetry and symmetry breaking are used to explain the emergence of space-time and matter in modern physics. Even molecular structures in chemistry are distinguished by mathematical symmetries. Their elegance and beauty seem to realize aesthetical categories in nature. In biological evolution, the question arises how symmetry breaking (e.g. molcular chirality) can be explained. In modern arts, symmetry and symmetry breaking are "hidden" structures which can be found in music, painting, and architecture. In a philosophical outlook, symmetry and symmetry breaking are highlighted as regulative guiding ideas of research. _______________________________________________________________________________________________________________________________________________________ This article is an extended version and English translation of my article "Symmetrie und Symmetriebrechung. Von der Urmaterie zu Kunst und Leben,“ in: Schriftenreihe der Heisenberg-Gesellschaft: Quanten 2 (ed. Konrad Kleinknecht), S. Hirzel Verlag, 9-59. An abridged version was presented in the EASA Colloquium Science meets Art (https://www.youtube.com/watch?v=nIUVNEQ7AR8 )

Orthogonal decomposition of symmetry model using sum-symmetry model for ordinal square contingency tables

Orthogonal decomposition of symmetry model using sum-symmetry model for ordinal square contingency tables

Electric Ferro-Axial Moment as Nanometric Rotator and Source of Longitudinal Spin Current

An electric ferro-axial moment, which is characterized by a nonzero expectation value of a time-reversal-even axial vector, exhibits distinct spatial-inversion and time-reversal properties from conventional ferroelectric, ferromagnetic, and ferro-magnetoelectric orders. Nevertheless, physical properties characteristic of the electric ferro-axial moment have been obscure owing to the absence of its conjugate electromagnetic fields. We theoretically investigate consequences of the presence of the ferro-axial moment on the basis of the symmetry and microscopic model analyses. We show that atomic-scale electric toroidal multipoles are the heart of the ferro-axial moment, which act as a nanometric rotator against external stimuli. Furthermore, we propose an intrinsic generation of a spin current parallel to an applied electric field in both metals and insulators. Our results not only provide a deep microscopic understanding of the role of the ferro-axial moment but also stimulate a new development for functional materials with use of the electric toroidal moment.

A Robust and Anonymous Three-Factor Authentication Scheme Based ECC for Smart Home Environments

With the rapid development of the Internet of Things (IoT) industry, the smart home is fully integrated with people’s shelter and transportation, which facilitates people’s daily life. A smart home without a security authentication mechanism will inevitably cause a series of security threats. This is essentially a problem of symmetry model worth solving. In fact, researchers have designed various authentication schemes to verify the identity of users and to ensure smart devices can be legally accessed through authorization in the smart home. In 2021, Yu proposed a three-factor anonymous authentication scheme for smart homes using lightweight symmetric encryption primitives and stated that their scheme is resistant to various known security attacks. However, after careful analysis, we found that Yu’s scheme needs further improvement in node capture attack and offline password guessing attack and that forward security cannot be guaranteed. Therefore, we first design a robust three-factor anonymous authentication scheme for smart homes based on asymmetric encryption Elliptic Curve Cryptography (ECC). Then, we perform formal and informal security analysis in which the formal analysis tools include Burrows-Abadi-Needham (BAN) logic and Scyther simulation tool to prove that the proposed scheme can achieve user anonymity, untraceability, and session key forward security. Meanwhile, mutual authentication is performed, and the scheme is resistant to all known attacks described in this article. Finally, a performance comparison is made in terms of efficiency, which shows that our scheme can have certain advantages with those newly designed schemes, achieve a delicate balance in performance and safety, and is more practical for the real smart home environment.

Personalized Relationships-Based Knowledge Graph for Recommender Systems with Dual-View Items

The knowledge graph has received a lot of interest in the field of recommender systems as side information because it can address the sparsity and cold start issues associated with collaborative filtering-based recommender systems. However, when incorporating entities from a knowledge graph to represent semantic information, most current KG-based recommendation methods are unaware of the relationships between these users and items. As such, the learned semantic information representation of users and items cannot fully reflect the connectivity between users and items. In this paper, we present the PRKG-DI symmetry model, a Personalized Relationships-based Knowledge Graph for recommender systems with Dual-view Items that explores user-item relatedness by mining associated entities in the KG from user-oriented entity view and item-oriented entity view to augment item semantic information. Specifically, PRKG-DI utilizes a heterogeneous propagation strategy to gather information on higher-order user-item interactions and an attention mechanism to generate the weighted representation of entities. Moreover, PRKG-DI provides a score feature as a filter for individualized relationships to evaluate users’ potential interests. The empirical results demonstrate that our approach significantly outperforms several state-of-the-art baselines by 1.6%, 2.1%, and 0.8% on AUC, and 1.8%, 2.3%, and 0.8% on F1 when applied to three real-world scenarios for music, movie, and book recommendations, respectively.

StarMap: a user-friendly workflow for Rosetta-driven molecular structure refinement.

Cryogenic electron microscopy (cryo-EM) data represent density maps of macromolecular systems at atomic or near-atomic resolution. However, building and refining 3D atomic models by using data from cryo-EM maps is not straightforward and requires significant hands-on experience and manual intervention. We recently developed StarMap, an easy-to-use interface between the popular structural display program ChimeraX and Rosetta, a powerful molecular modeling engine. StarMap offers a general approach for refining structural models of biological macromolecules into cryo-EM density maps by combining Monte Carlo sampling with local density-guided optimization, Rosetta-based all-atom refinement and real-space B-factor calculations in a straightforward workflow. StarMap includes options for structural symmetry, local refinements and independent model validation. The overall quality of the refinement and the structure resolution is then assessed via analytical outputs, such as magnification calibration (pixel size calibration) and Fourier shell correlations. Z-scores reported by StarMap provide an easily interpretable indicator of the goodness of fit for each residue and can be plotted to evaluate structural models and improve local residue refinements, as well as to identify flexible regions and potentially functional sites in large macromolecular complexes. The protocol requires general computer skills, without the need for coding expertise, because most parts of the workflow can be operated by clicking tabs within the ChimeraX graphical user interface. Time requirements for the model refinement depend on the size and quality of the input data; however, this step can typically be completed within 1 d. The analytical parts of the workflow are completed within minutes.

Optimization of COMPASS-U Support Structure

The global support structure for Compass Upgrade (COMPASS-U) employs many bolted and pinned components to improve the manufacturability of the whole structures. This is a departure from other designs used for highly loaded tokamaks, like Alcator C-Mod which used large forgings. Modeling of the numerous connections and interfaces was a challenge. This article will describe how to optimize the C-frame support structure with the goal to eliminate differential displacements at those interfaces and, importantly, minimize toroidal mutual displacement at the sliding joint of the toroidal field (TF) coils. The global support structure consists of 16 C-frames, and it can be simplified as a 1/8th cyclic symmetry model due to the eight vertical rods mounting that connect bottom CS and PF1-3 assemblies to the C-frames. Structure variants with different connection webs between two neighboring C-frames have been analyzed. The preloading of bolts can be split into several preload substeps to simulate the real assembly process of the COMPASS-U support structure. The TF crown and the wedge plate can be further improved to become a solid part to better hold the TF coils.

Simulating continuous symmetry models with discrete ones

Especially in one dimension, models with discrete and continuous symmetries display different physical properties, starting from the existence of long-range order. In this work, we that, by adding topological frustration, an antiferromagnetic $XYZ$ spin chain, characterized by a discrete local symmetry, develops a region in parameter space that mimics the features of models with continuous symmetries. For instance, frustration closes the mass gap and we describe a continuous crossover between ground states with different quantum numbers, a finite (Fermi) momentum for low energy states, and the disappearance of the finite order parameter. Moreover, we observe nontrivial ground-state degeneracies, nonvanishing chirality, and a singular foliation of the ground-state fidelity. Across the boundary between this chiral region and the rest of the phase diagram, any discontinuity in the energy derivatives vanishes in the thermodynamic limit.

On singularity points in elastic orthorhombic media

The analysis of singularity points in anisotropic models of low symmetry is very important for seismic modelling and seismic data processing. Ray tracing: the group velocity vector dramatically changes the orientation in vicinity of singularity point. Seismic amplitudes: the relative geometrical spreading of seismic wave tends to zero in singularity point. Seismic wave polarization: the polarization vectors dramatically change in vicinity of singularity point. Multiarrival: one of the waves has triplication associated with singularity point, another wave has a lacuna.The singularity points are considered for elastic anisotropic model with orthorhombic symmetry. The conditions for the presence of singularity points are derived depending on location of these points, in symmetry plane and in-between the symmetry planes. The explicit equations for images of the singularity points in group velocity domain are derived. The conditions for different types of degeneracy of these images are defined. We also perform the analysis of interaction of the group velocity images of different singularity points.

Parsimonious Bivariate T-distribution Type Symmetry Models for Square Contingency Tables

For square contingency tables with ordered categories, Iki, Ishihara and Tomizawa (2013) considered the t-distribution type symmetry model and Iki, Okada and Tomizawa (2018) extended this model. These models are appropriate for a square contingency table if it is reasonable to assume an underlying bivariate t-distribution having any degrees of freedom. This study proposes three kinds of parsimonious models for these models. Additionally, this paper provides the decompositions of the parsimonious symmetry model using the proposed model. Some simulation studies based on bivariate t-distribution show the performances of the proposed models.

Study on Combustion Kinetic Characteristics of Lignite and Semi-coking Dust.

In order to master the combustion kinetic characteristics of semi-coking dust in the early pyrolysis stage of lignite combustion explosion, a vacuum tube furnace was used to prepare semi-coking dust with different pyrolysis degrees, and the experimental samples were studied by a synchronous differential thermal analyzer. By means of theoretical analysis, the reaction mechanism of lignite and semi-coking dust was revealed. The results show that when the final pyrolysis temperature rises to 920 °C, the percentage of volatile matter decreases by 94.6%. The reaction in this process also causes the original pores to be cross-linked and collapsed, and a large number of new pores are generated, and the original pore structure is significantly enlarged. With the increase of the final temperature of pyrolysis, the ignition temperature (Tb) of the dust increased from 354 to 455 °C, the fastest reaction temperature (Tc) increased from 399 to 495 °C, and the ember temperature (Td) increased from 558 to 658 °C. The maximum combustion rate decreased by 65.97%, and the average combustion rate decreased by 84.67%. The apparent activation energy increased by 4.7 times from 45.219 to 257.665 kJ/mol, and the combustion kinetics of semi-coke became worse. The thermal reaction of lignite and semi-coking dust conforms to the diffusion mechanism of the three-dimensional spherical symmetry model. The research results provide a new idea for discussing the mechanism of coal dust explosion and the development of explosion suppression technology.

Discrete Dynamic Model of a Disease-Causing Organism Caused by 2D-Quantum Tsallis Entropy

Many aspects of the asymmetric organ system are controlled by the symmetry model (R&L) of the disease-causing organism pathway, but sensitive matters like somites and limb buds need to be shielded from its influence. Because symmetric and asymmetric structures develop from similar or nearby matters and utilize many of the same signaling pathways, attaining symmetry is made more difficult. On this note, we aim to generalize some important measurements in view of the 2D-quantum calculus (q-calculus, q-analogues or q-disease), including the dimensional of fractals and Tsallis entropy (2D-quantum Tsallis entropy (2D-QTE)). The process is based on producing a generalization of the maximum value of the Tsallis entropy in view of the quantum calculus. Then by considering the maximum 2D-QTE, we design a discrete system. As an application, by using the 2D-QTE, we depict a discrete dynamic system that is afflicted with a disease-causing organism (DCO). We look at the system’s positive and maximum solutions. Studies are done on equilibrium and stability. We will also develop a novel design for the fundamental reproductive ratio based on the 2D-QTE.

Nonlinear nonreciprocal transport in antiferromagnets free from spin-orbit coupling

We theoretically propose a realization of a nonlinear nonreciprocal transport in antiferromagnets without relying on the relativistic spin-orbit coupling. Through the symmetry and microscopic model analyses, we show that a local spin scalar chirality to induce an asymmetric band modulation becomes a source of a Drude-type nonlinear transport, while an electric polarization induced by a collinear spin configuration in a triangle unit leads to a Berry-curvature-dipole-type nonlinear transport. We demonstrate that 120$^\circ$ antiferromagnetic ordering on a triangular lattice and a breathing kagome lattice in an external magnetic field are typical examples. Our results open a new direction of designing and engineering functional materials with showing rich parity-violating transport phenomena by spontaneous magnetic phase transitions.

Impact of Information Asymmetry on the Operation of Green Closed-Loop Supply Chain under Government Regulation

Recycling subsidy and carbon tax policies are ways to achieve energy and environmental sustainability. The implementation of these policies has changed the operating environment of traditional closed-loop supply chains, while the privacy of relevant information increases the difficulty of decision-making. Under the background, this paper considers the green closed-loop supply chain (GCLSC) under the hybrid policy of recycling subsidy and carbon tax where the manufacturer is in charge of recycling and the retailer invests in green marketing. Taking green marketing cost coefficient as the retailer’s private information, this paper explores the influence of information asymmetry on optimal decisions and performance of the GCLSC. By constructing game models of information symmetry and asymmetry, the optimal decisions, economic and environmental performance, and social welfare are provided. Combined with numerical analysis, the influence of uncertainty of the manufacturer’s estimation, subsidies and carbon tax on the GCLSC is proposed. The results indicate that the uncertainty in the manufacturer’s estimation can improve the social welfare under certain conditions, but it cannot reduce carbon emissions. Recycling subsidy and carbon tax policies oppositely affect the manufacturer’s optimal decisions and carbon emissions. Information asymmetry is beneficial to the retailer. However, less uncertainty in estimation is not always better for the manufacturer. The manufacturer needs to proactively adopt strategies to stimulate the retailer’s information sharing.