Earlier Paper Research Articles

Mutating signed -exceptional sequences

AbstractWe establish some properties of $\tau$ -exceptional sequences for finite-dimensional algebras. In an earlier paper, we established a bijection between the set of ordered support $\tau$ -tilting modules and the set of complete signed $\tau$ -exceptional sequences. We describe the action of the symmetric group on the latter induced by its natural action on the former. Similarly, we describe the effect on a $\tau$ -exceptional sequence obtained by mutating the corresponding ordered support $\tau$ -tilting module via a construction of Adachi-Iyama-Reiten.

Outlier detection in cylindrical data based on Mahalanobis distance

Cylindrical data are bivariate data formed from the combination of circular and linear variables. Identifying outliers is a crucial step in any data analysis work. This paper proposes a new distribution-free procedure to detect outliers in cylindrical data using the Mahalanobis distance concept. The use of Mahalanobis distance incorporates the correlation between the components of the cylindrical distribution, which had not been accounted for in the earlier papers on outlier detection in cylindrical data. The threshold for declaring an observation to be an outlier can be obtained via parametric or non-parametric bootstrap, depending on whether the underlying distribution is known or unknown. The performance of the proposed method is examined via extensive simulations from the Johnson-Wehrly distribution. The proposed method is applied to two real datasets, and the outliers are identified in those datasets.

Increasing the friction stress decreases the size dependence of strength in a family of face-centered cubic high- and medium-entropy alloy micropillars

Size effects (‘smaller is stronger’) are important aspects of the mechanical behavior of materials. Experimentally, they are usually probed by performing compression tests on micropillars of different sizes (cross-sectional areas). To overcome limitations associated with comparing different crystal structures and to better handle the influence of melting points in different metals, single crystal face centered cubic (fcc) micropillars of equiatomic binary, ternary, and quaternary medium-entropy alloy (MEA) subsystems of the quinary CrMnFeCoNi high-entropy alloy (HEA) were tested. All eight alloys investigated were single-phase solid solutions having the fcc crystal structure. Their melting temperatures varied only over a narrow range (1189-1462 °C). They exhibit a size-dependent critical resolved shear stress (CRSS ∝ d-n, where d is the pillar diameter, n is a power law exponent). The results show that, all else being equal, size effects scale inversely with friction stress. In contrast, there is no systematic dependence on configurational entropy, contrary to speculations in some earlier papers that solid solution strengthening would increase as the number of alloying elements increases. ‘Bulk’ CRSS values were estimated by extrapolating the measured CRSS values of pillars with diameters of approximately 1-8 μm to larger pillar sizes of 30 μm. Good agreement was found with available CRSS values of bulk single crystals. It is concluded that it is possible to obtain bulk CRSS values more reliably from micropillar tests than from the Taylor factor corrected yield strengths of bulk polycrystals.

Proper Edge Colorings of Cartesian Products with Rainbow C_4-s

Related to the famous (7,4)-problem, in an earlier paper we introduced B-colorings. We call a proper edge coloring of a graph G a B-coloring if every 4-cycle of G is colored with four different colors. Let q_B(G) denote the smallest number of colors needed for a B-coloring of G. Here we look at q_B(G) for Cartesian products of paths and cycles. Our main result is that q_B(G) is equal to the chromatic index of G for grids, i.e. for Cartesian products of paths (apart from a few exceptions). This extends an earlier result for the case when G is the d-dimensional cube. Our main tool is a lemma which gives q_B(Gsquare H)le q_B(G)+q_B(H) if chi (G)le q_B(H), chi (H)le q_B(G), where chi (G) is the chromatic number of G.

Magnetic properties of V[formula omitted]MnGa, V[formula omitted]MnAl, V[formula omitted]FeGa and V[formula omitted]FeAl

The investigated materials belong to Heusler compounds and are similar in composition to titanium-based analogs, like Ti2MnAl, which was suspected of exhibiting Spin Gapless Semiconductor (SGS) or Weyl semimetal state in some earlier papers. The vanadium-based materials are not well known in earlier reports. We show the results of our XRD analysis of the synthesized samples, their magnetic properties, and their resistivity measured vs. temperature as well as magnetic field. Heusler compounds can crystallize in simple or inverted structures, here we try to resolve which one is more probable in these materials and whether the SGS state can exist in them or not. From our measurements it is clear that in these samples both of those crystal structures coexist, and they do not show signs of long range magnetic ordering. The ground state obtained from our ab-initio calculations should be magnetic for both structural models, which means that the disorder induced by the coexistence of those two structures at the same time eliminates the long-range magnetic ordering.

Fibration theorems à la Milnor for analytic maps with non-isolated singularities

AbstractWe study the topology of real analytic maps in a neighborhood of a (possibly non-isolated) critical point. We prove fibration theorems à la Milnor for real analytic maps with non-isolated critical values. Here we study the situation for maps with arbitrary critical set. We use the concept of d-regularity introduced in an earlier paper for maps with an isolated critical value. We prove that this is the key point for the existence of a Milnor fibration on the sphere in the general setting. Plenty of examples are discussed along the text, particularly the interesting family of functions $$(f,g):{\mathbb {R}}^n \rightarrow {\mathbb {R}}^2$$ ( f , g ) : R n → R 2 of the type $$\begin{aligned} (f,g) = \left( \sum _{i=1}^n a_i x_i^p, \sum _{i=1}^n b_i x_i^q \right) , \end{aligned}$$ ( f , g ) = ∑ i = 1 n a i x i p , ∑ i = 1 n b i x i q , where $$a_i, b_i \in {\mathbb {R}}$$ a i , b i ∈ R are constants in generic position and $$p,q \ge 2$$ p , q ≥ 2 are integers.

Twisted GGP problems and conjectures

In a series of three earlier papers, we considered a family of restriction problems for classical groups (over local and global fields) and proposed precise answers to these problems using the local and global Langlands correspondence. These restriction problems were formulated in terms of a pair $W \subset V$ of orthogonal, Hermitian, symplectic, or skew-Hermitian spaces. In this paper, we consider a twisted variant of these conjectures in one particular case: that of a pair of skew-Hermitian spaces $W = V$.

A statistical analysis of the second ‘pop-in’ behaviour of the spherical-tip nanoindentation of Zr-based bulk metallic glasses

Statistical analyses of the shear stresses, τy, at which the first ‘pop-ins’ occur during the spherical tip nanoindentation of a wide variety of materials is often conducted to understand the micromechanisms of incipient plasticity. In an earlier paper, we reported such a study on data generated on several different Zr-based bulk metallic glasses (BMGs) using a wide range of experimental variables, such as the tip radius, Ri, loading rate, P˙, and structural state of the glass. In the present work, we analyse the second pop-in stress, τ2, data employing the expectation maximization algorithm in conjunction with the Akaike Information Criterion to examine which of the single and mixed (bimodal) versions of the Gaussian, Lognormal and Weibull (both 2 and 3 parameter) statistical models best describes the stochasticity of τ2. Results show that the 3-parameter Weibull distribution also captures the stochasticity of τ2, just as it does for τy. For datasets of τ2 that are generated with larger Ri and P˙, the bimodal 3-parameter Weibull distribution is a better descriptor of the dispersion. While Weibull exponent, m, of τ2 datasets is marginally higher than that of τy, their kernel density estimates (KDEs) are similar. However, there is a relative shift of the KDEs of τ2 to smaller values compared to that of τy. From mechanistic arguments, τ2 is determined as the stress to nucleate a second shear band over a previously formed shear band and its stochasticity is attributed solely to the mechanical heterogeneity of the material within it. On this basis, the average shear strength of the shear band is estimated to be ∼8–11% and 15–17% lower than the strength of the undeformed BMG in the as cast condition and structurally relaxed conditions, respectively. This study provides an understanding of how plasticity develops in BMGs during nanoindentation.

Universal Chern number statistics in random matrix fields

We investigate the probability distribution of Chern numbers (quantum Hall conductance integers) for a parametric version of the GUE random matrix ensemble, which is a model for a chaotic or disordered system. The numerically-calculated single-band Chern number statistics agree well with predictions based on an earlier study [O. Gat and M. Wilkinson, SciPost Phys., 10, 149, (2021)] of the statistics of the quantum adiabatic curvature, when the parametric correlation length is small. However, contrary to an earlier conjecture, we find that the gap Chern numbers are correlated, and that the correlation is weak but slowly-decaying. Also, the statistics of weighted sums of Chern numbers differs markedly from predictions based upon the hypothesis that gap Chern numbers are uncorrelated. All our results are consistent with the universality hypothesis described in the earlier paper, including in the previously unstudied regime of large correlation length, where the Chern statistics is highly non-Gaussian.

EVENT MANAGEMENT IN SOCIAL ENTREPRENEURSHIP: A BIBLIOMETRIC ANALYSIS

Social entrepreneurship is a growing phenomenon that is currently attracting much public attention due to its potential to reduce social problems and improve people's well-being. Events hosted by social entrepreneurs may present vital chances for venues to enhance the event's goal and happiness. This study aims to (1) examine event management and social entrepreneurship while focusing on the relationships, dimensions, and context-specific functions that each play, and (2) identify the link between social entrepreneurship and event management so that it can be used to construct future theories. This study uses VOSviewer to visualize how event management and social entrepreneurship were meant from numerous earlier papers using bibliometric analysis. The findings of this study will contribute to our understanding of how event management may be used in social entrepreneurship to increase behavioral intention and improve event experiences. For further research, the recommendations listed below are provided. Researchers may also develop new theories and event management literature to further the discussion and research on this subject.

Microplastic–Pharmaceuticals Interaction in Water Systems

Microplastics, MPs, in aquatic environments pose serious threats when associated with other pollutants, such as pharmaceuticals, PHs. This review is a continuation of an earlier paper on the role of MPs as containers and carriers of heavy metals, HMs, persistent organic pollutants, POPs, pharmaceuticals, PHs, and personal care products, PCPs, in marine environments and published in the Journal of Marine Science and Engineering. The current effort aims to elucidate the most recent data on the interaction and association of MPs with PHs and the ecotoxicological implications on food webs. This review focuses on the nature of the interaction from different perspectives, such as the hydrophobicity and hydrophilicity of the polymer and drug, the polymer surface, and the rate of weathering. The effects of environmental conditions, such as mechanical stress, photodegradation, pH, salinity, dissolved organic matter, and gastrointestinal features of marine biota, were reported. This review reports on experimental laboratory, mathematical, and field data on MPs’ carrier and accumulation role in PHs and their release and ecotoxicological effects on water bodies. From the survey of the data, it emerges that the nature of the interaction and the effects on biota are very complex and variable, and perhaps only a systematic mechanic approach of data collection with a statistical approach using big data and deep learning will contribute in the future to clarify.

A review and analysis of errors in post‐stack time‐shift interpretation

AbstractThis study complements two earlier papers on the interpretation and estimation of post‐stack time‐shifts that detail the most popular measurement methods to date. In this current work, the focus is on describing the magnitude and identifying the origin of the uncertainty present in these time‐shift values. We also consider how the underlying assumptions behind conventional time‐shift estimation methods can contribute to the inadequate resolution of the subsurface time‐lapse changes. The various errors fall into three broad categories: (1) those related to intrinsic data limits that cannot be avoided; (2) those associated with seismic measurement methods that can be corrected with some effort; and finally (3) those that arise due to approximations to the wave physics made during the design or implementation of the methods. In the first category are limitations due to sampling rate and signal‐to‐noise ratio, and wavelet interferences resulting from the narrow band nature of the seismic data and the heterogeneous nature of the geology itself. The effects produce errors of typically a fraction of a millisecond, but exceptionally in 4D data with poor repeatability up to 1 ms. In the second category are acquisition and processing errors. These are usually of the order of a few milliseconds but can reach up to 10s of milliseconds and are, therefore, essential to correct. It is possible to correct the effects of tides and seawater variations in marine acquisition if these changes are monitored and measured. Navigation and timing are identified as issues to consider carefully. For land data, daily and seasonal near‐surface variations are still problematic, and source and sensors must be buried to deliver interpretable time‐shifts. The impact of choices made during processing can be significant but is specific to the workflow and dataset and thus cannot be generically assessed. However, the effects from residual multiples can be identified and treated. Of moderate importance is the third category of errors, which consists of four items. Of these, the effect of lateral image shifts and amplitude effects are judged to play a minor role. Deviation from the assumption of vertical ray‐paths during post‐stack analysis appears to be of concern only for reservoirs with noticeably dipping structures and strong contrasts. The effect of pre‐stack variations on the post‐stack measurements remains a topic to be more thoroughly examined, and the conclusion is unclear. Finally, it is apparent that uncertainties in all categories are strongly dependent on the field setting and geographical location.

Local model dynamics for two qubits

The density matrix model described in an earlier paper “Model Dynamics for Quantum Computing” is applied to the case of two qubits. The earlier paper provided a density matrix dynamics with unitary time-dependent gates including qubit energy splitting, entropy constraints, external bath and noise effects. The Lindblad formulation as extended by Beretta was adopted in designing this model. Visualization was provided by examining the time-evolution of the polarization vector. In this paper, the same ideas are applied to two-qubit systems, where there are now 15 time-dependent observables; namely, six polarization vectors (P→A,P→B), and nine spin-correlations (T↔). These time-dependent observables provide ready visualization of two qubit dynamics. Special emphasis is placed on the CNOT gate, which is implemented following recent outstanding developments in using silicon-based dots. By invoking a different splitting for each qubit, plus a spin–spin interaction and a carefully designed Rabi oscillation, a CNOT gate is generated. Careful analysis of the time-dependence of these aspects provides insight into CNOT dynamics. The model can be used to ascertain the sensitivity and efficacy of such a CNOT gate when subject to external environmental effects such as noise disturbances, and noise compensation, using the single-system formulation of steepest-entropy-ascent (SEA) non-equilibrium quantum thermodynamics, suitable to model controlled-gate implementations as long as the two qubits remain localized and effectively behave as a single physical four-level system. The role of careful timing in constructing an efficient CNOT gate is illustrated. The formation of Bell states and the evolution of entanglement including noise, bath and entropy considerations are examined. Extensions to the two-qubit swap, and to the three-qubit Toffoli gate dynamics are outlined. It is also shown that a simple Lindblad form can be used to introduce weak and distinct qubit noise pulses. A simple scheme for noise compensation is designed to increase purity and decrease entropy, without invocation of quantum correction methodology. It is based on using the preexisting entanglement of the environment with the quantum system and carefully designed non-Hermitian Lindblad pulses.

Societal Impacts of Open Government Data Use

The purpose of this research is to investigate the impacts of Open Government Data (OGD) use on the societal-economic sphere and to identify possible gaps in the literature between its several categories. Therefore, this paper led to a deliberate literature study of the OGD research that primarily collected on empirical earlier papers. We systematically reviewed 88 reputable articles connected with the societal impacts of OGD use utilising Scopus Gateway from 2012 to 2022. We followed the Prefered Reporting Items for Systematic Review and Meta-Analysis (PRISMA) Protocol, and several software tools such as Mendeley, Publish or Perish, and VOSViewer to support the literature review process. This research provides several essential statistical views related to the social impact in the OGD field using Altmetric. The result shows that there were 26 categories of the OGD used for the societal consequences, with 8 main keywords most frequently used by the authors. Additionally, the highest number of authors who contributed to the discussion of social impact data, especially on the issue of open government, was 19, recorded in 2012. A number of topics overwhelmed the discussion of social impacts, namely, open government, citizen engagement, socio-economic value, and transparency in the period of 2015 and 2017.

Beyond the Divide: A Century of Canadian Mosque Design

Muslim immigrants first pray in each other homes, and later in the basement of churches and rented premises. They progress to buying an existing building and repurpose it to serve as a mosque. Finally, the fledgling community raises the funds to buy land and build a mosque that reflects both their native nostalgia and aspirations as new Canadians. A century of mosque-building by Muslim immigrants to Canada is such an expatriate phenomenon. However, the “Divide” in the title refers not to crossing the oceans but to another telling subtitle from the author’s ear-lier paper with the same title: “Women’s Spaces in Canadian Mosques.” The two subtitles, one documentary (book) and the other didactic (paper), vie for the reader’s attention, crossing the genre divide.

Further results on outer independent 2-rainbow dominating functions of graphs

Let G = (V(G), E(G)) be a graph. A function f : V(G) → ℙ({1, 2}) is a 2-rainbow dominating function if for every vertex v with f(v) = ∅, f(N(v)) = {1, 2}. An outer-independent 2-rainbow dominating function (OI2RD function) of G is a 2-rainbow dominating function f for which the set of all v 2208 V(G) with f(v) = ∅ is independent. The outer independent 2-rainbow domination number (OI2RD number) γoir2(G) is the minimum weight of an OI2RD function of G. In this paper, we first prove that n/2 is a lower bound on the OI2RD number of a connected claw-free graph of order n and characterize all such graphs for which the equality holds, solving an open problem given in an earlier paper. In addition, a study of this parameter for some graph products is carried out. In particular, we give a closed (resp. an exact) formula for the OI2RD number of rooted (resp. corona) product graphs and prove upper bounds on this parameter for the Cartesian product and direct product of two graphs.

STUDY ON EARLY SCREENING OF GANODERMA DISEASE SUSCEPTIBILITY/TOLERANCE IN PRE-NURSERY POT-TRAY SYSTEM - PART 2 (RELATIONSHIP OF SCREENED OIL PALM PROGENY TOWARDS GANODERMA TOLERANCE AND LIGNOCELLULOSIC CONTENT)

Screening of Ganoderma disease tolerant oil palm progenies may provide a practical solution towards basal stem rot, a major disease affecting the oil palm industries of Malaysia and Indonesia. Through the method developed in an earlier paper (part 1), Ganoderma tolerant oil palm planting material was successfully identified among different oil palm progenies through pre-nursery pot-tray system. In this study, reported in the present paper (part 2), the root lignocellulosic content of 35-week-old control seedlings from 19 progenies tested in the earlier paper (part 1) were determined. Based on the results, the summation of cellulose, hemicellulose and lignin contents had a significant correlation (p < 0.05) with average days from first symptom to confirmed death (DTD) whereas cellulose was seen to be weakly correlated with average days from inoculation to first symptom (DTFS) at p-value < 0.10. However, lignin content in roots were not significantly correlated with any of the parameters used to characterise tolerance and resistance of inoculated plants in Ganoderma tolerance. The present result indicates that the lignin content of healthy control seedlings planted without Ganoderma inoculation is not a dependable parameter to characterise the tolerance of a progeny towards Ganoderma. Keywords: Ganoderma disease, root lignocellulosic content, correlation.

Distributive FCP extensions

We are dealing with extensions of commutative rings [Formula: see text] whose chains of the poset [Formula: see text] of their subextensions are finite (i.e. [Formula: see text] has the FCP property) and such that [Formula: see text] is a distributive lattice, that we call distributive FCP extensions. Note that the lattice [Formula: see text] of a distributive FCP extension is finite. This paper is the continuation of our earlier papers where we studied catenarian and Boolean extensions. Actually, for an FCP extension, the following implications hold: Boolean [Formula: see text] distributive [Formula: see text] catenarian. A comprehensive characterization of distributive FCP extensions actually remains a challenge, essentially because the same problem for field extensions is not completely solved. Nevertheless, we are able to exhibit a lot of positive results for some classes of extensions. A main result is that an FCP extension [Formula: see text] is distributive if and only if [Formula: see text] is distributive, where [Formula: see text] is the integral closure of [Formula: see text] in [Formula: see text]. A special attention is paid to distributive field extensions.

Hegel’s Bellicis View of War. Mature Works

In “The Phenomenology of Spirit” and “Philosophy of Right”, Hegel gives a detailed specification of the theses about the war that were claimed in earlier papers and manuscripts, but his position is not fundamentally changed. In the “The Phenomenology of Spirit” Hegel advocates governments’ need and right to initiate a war from time to time in order to prevent both the isolation and atomization, and let individuals feel the death. As in the past, the war, as Hegel says, has a moment of ethical life. In the “Philosophy of Right” Hegel introduces final deliberations about war that rely on ideas of his earlier paper about natural law even more than in the “The Phenomenology of Spirit”. Hegel emphasizes the ethical role of sacrifice in the war and expresses opinions critical of not an abstract perpetual peace but a concrete philosophical project of Kant. Due to Hegel, Kant’s perpetual peace does not resemble a perpetual deception, since the required union of states is elusive and none except the world spirit in the world history can be a praetor. In line with Heraclitus, Hegel maintains that wars underlie the nature of things. I contribute to the discussions of Hegel scholars if Hegel’s philosophy glorifies a war or not as follows: I substitute the term “glorification” with the term “bellicisme” that suits better to measured, not snobbish and deprived of certain historical implications Hegel’s theses about reasonableness, necessity, the ethicality of war and ethicality of perpetual peace illness.

Machine learning-enhanced search for a vectorlike singlet B quark decaying to a singlet scalar or pseudoscalar

The presence of a new decay mode relaxes the current mass exclusion limits on vectorlike quarks considerably. We consider the case of a weak-singlet vectorlike $B$ quark that can decay to a singlet scalar or pseudoscalar $\Phi$. In an earlier paper [A. Bhardwaj et al., Roadmap to explore vectorlike quarks decaying to a new scalar or pseudoscalar, Phys. Rev. D, 106 (2022) 095014; arXiv:2203.13753], we mapped the possibilities to explore such setups at the LHC. We showed that it is possible for a $B$ quark to decay into $\Phi$ and the $\Phi$ to dominantly decay to a pair of gluons or $b$ quark(s) without fine-tuning the parameters. In this paper, we present a collider search strategy to look for the pair production of singlet $B$ quarks. If both $B$ quarks decay into $b\Phi$ pairs, the final state is fully hadronic: $B{B}\to(b\Phi)({b}\Phi)\to (bgg)({b}gg)/(bb{b})({b}b{b})$, which is very challenging to probe. Therefore, we consider a simpler mixed decay specific to the singlet $B$ case, $BB\to(b\Phi)(tW)$ with a lepton in the final state, to achieve the best sensitivity at the high-luminosity LHC. We use a deep neural network with a weighted cross-entropy loss to separate the signal from the huge SM background. Our analysis shows that large areas of the $M_{B}-M_{\Phi}$ parameter space are discoverable through this signature. We show how the discovery and exclusion regions scale with the branching ratio in the new decay mode. We also estimate the reach in the inclusive monolepton channel with the same network model.