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Source code authorship attribution is an important problem in practical applications such as plagiarism detection, software forensics, and copyright disputes. Recent studies show that existing methods for source code authorship attribution can be significantly affected by time evolution, leading to a decrease in attribution accuracy year by year. To alleviate the problem of Deep Learning (DL)-based source code authorship attribution degrading in accuracy due to time evolution, we propose a new framework called TimeDomain Adaptation (TimeDA) by adding new feature extractors to the original DL-based code attribution framework that enhances the learning ability of the original model on source domain features without requiring new or more source data. Moreover, we employ a centroid-based pseudo-labeling strategy using neighborhood clustering entropy for adaptive learning to improve the robustness of DL-based code authorship attribution. Experimental results show that TimeDA can significantly enhance the robustness of DL-based source code authorship attribution to time evolution, with an average improvement of 8.7% on the Java dataset and 5.2% on the C++ dataset. In addition, our TimeDA benefits from employing the centroid-based pseudo-labeling strategy, which significantly reduced the model training time by 87.3% compared to traditional unsupervised domain adaptive methods. [ABSTRACT FROM AUTHOR]

Partial discharge (PD) in cavities can lead to a breakdown in solid insulation and, therefore, indicate the onset of aging in electrical equipment. It is necessary to investigate the activity of single- and double-cavity PD under aging conditions, which is the focus of this study. The results obtained can be useful in monitoring the condition of insulation systems. The factors (pressure, effective work function, and charge decay time constant) that influence PD behaviour under different test conditions were permutated in a PD model. The simulation results agree with measurements obtained for the same applied voltage. The model can generate PD pulse distribution shapes similar to the measured PD of single and double cavities. Both turtle-like and rabbit-ear-like phase-resolved PD (PRPD) patterns were observed during the aging process of the samples in both double and single cavities. This study concludes that the identification of the PD pattern achieved in this work for closely coupled cavities is a step towards characterizing multiple defects phenomena through PD evolution patterns. [ABSTRACT FROM AUTHOR]

In this paper, in the classical framework, the lower bounds for the sensitivities of the generalized Lemaitre Tolman Bondi metric are evaluated. The calculated lower bounds via the linear dynamical systems L∂∂θ$L_{\frac{\partial }{\partial \theta }}$, L∂∂r$L_{\frac{\partial }{\partial r}}$, and L∂∂ϕ$L_{\frac{\partial }{\partial \phi }}$ are −ln2+ln|(ṘB)2−(R′)2|−2ln|B|$-\ln 2+\ln|{(\dot{R}B)}^{2}-{(R^{\prime })}^{2}|-2\ln|B|$, 2ln|Ḃ|−ln2$2\ln|\dot{B}|-\ln 2$ and −ln2−2ln|B|+ln|(Ṙ2B2−R′2)sin2θ−B2cos2θ|$-\ln 2-2\ln|B|+ \ln |(\dot{R}^{2}B^{2}-R^{\prime 2})\sin ^{2}\theta -B^{2}\cos ^{2}\theta|$ respectively. The sensitivities and the lower sensitivities via L∂∂t$L_{\frac{\partial }{\partial t}}$ are zero are also shown. In the quantum framework, the properties of the Einstein‐Vaz shells which are the final result of the quantum gravitational collapse arising from the Lemaitre Tolman Bondi discussed by Vaz in 2014 are analyzed. In fact, Vaz showed that continued collapse to a singularity can only be obtained if one combines two independent and entire solutions of the Wheeler‐DeWitt equation. Forbidding such a combination leads naturally to matter condensing on the Schwarzschild surface during quantum collapse. In that way, an entirely new framework for black holes (BHs) has emerged. The approach of Vaz was also consistent with Einstein's idea in 1939 of the localization of the collapsing particles within a thin spherical shell. Here, following an approach of oned of us (CC), we derive the BH mass and energy spectra via a Schrodinger‐like approach, by further supporting Vaz's conclusions that instead of a spacetime singularity covered by an event horizon, the final result of the gravitational collapse is an essentially quantum object, an extremely compact "dark star". This "gravitational atom" is held up not by any degeneracy pressure but by quantum gravity in the same way that ordinary atoms are sustained by quantum mechanics. Finally, the time evolution of the Einstein‐Vaz shells is discussed. In this paper, in the classical framework, the lower bounds for the sensitivities of the generalized Lemaitre Tolman Bondi metric are evaluated. In the quantum framework, the properties of the Einstein‐Vaz shells which are the final result of the quantum gravitational collapse arising from the Lemaitre Tolman Bondi discussed by Vaz in 2014 are analyzed. In fact, Vaz showed that continued collapse to a singularity can only be obtained if one combines two independent and entire solutions of the Wheeler‐DeWitt equation. Forbidding such a combination leads naturally to matter condensing on the Schwarzschild surface during quantum collapse. In that way, an entirely new framework for black holes (BHs) has emerged. The approach of Vaz was also consistent with Einstein's idea in 1939 of the localization of the collapsing particles within a thin spherical shell. Here, following an approach of oned of us (CC), we derive the BH mass and energy spectra via a Schrodinger‐like approach, by further supporting Vaz's conclusions that instead of a spacetime singularity covered by an event horizon, the final result of the gravitational collapse is an essentially quantum object, an extremely compact "dark star". This "gravitational atom" is held up not by any degeneracy pressure but by quantum gravity in the same way that ordinary atoms are sustained by quantum mechanics. Finally, the time evolution of the Einstein‐Vaz shells is discussed. [ABSTRACT FROM AUTHOR]

We investigated the time evolution of the symmetry of symbols constituting alphabets rooted in the Phoenician script. A diversity of quantitative measures of symmetry of graphemes appearing in Phoenician, Western Greek, Etruscan from Marsiliana, Archaic Etruscan, Neo-Etruscan, Euclidian Greek, Archaic and Classical Latin and Proto-Hebrew scripts, constituting the Phoenician script family, were calculated. The same measures were established for the Hebrew/Ashurit and English scripts. The Shannon-like measures of symmetry were computed. The Shannon diversity index was calculated. Our findings indicate that the Shannon diversity index increased with time in a monotonic way for the studied scripts. The diversity of symmetry groups inherent for addressed alphabets grows with time. We also introduced the symmetry factor of the alphabet. The symmetry factor quantifies the averaged level of symmetrization of the alphabet and the possible parsimony of graphical information necessary for the drawing of the entire set of graphemes constituting the alphabet. We found that the symmetry factor is decreased with time for the alphabets rooted in the Phoenician script. This means that the average level of symmetrization of the studied alphabet increases with time. The parsimony of graphical information necessary for writing graphemes is consequently increased with time. The values of the symmetry factor calculated for the addressed scripts are close to one another, with the pronounced exception of the Hebrew/Ashurit script. Our study supplies the arguments for the point of view, according to which the modern Hebrew/Ashurit script did not emerge from the Phoenician one. [ABSTRACT FROM AUTHOR]

Abstract Purposes The aim of this study is to investigate the time evolution of active caspase 3 within first 120 h in the rat lens after in vivo exposure to subthreshold dose of UVR-B. Methods Twenty three six-week-old female albino Sprague-Dawley rats were exposed to subthreshold dose (1 kJ/m2) of UVR-B unilaterally and sacrificed at 24, 41, 70 and 120 h after exposure. Lenses were enucleated and active caspase 3 was detected by Western Blot. The time evolution of active caspase 3 was then plotted as a function of relative mean difference in active caspase 3 between exposed and nonexposed lenses. Results There is expression of active caspase 3 in both exposed and nonexposed lenses but there is no difference in relative mean difference in active caspase 3 between exposed and nonexposed lenses in all four postexposure groups. Conclusions Exposure to subthreshold dose of UVR-B does not induce apoptosis in the rat lens in vivo within first 120 h though there is a non-significant increase of active caspase 3 at 120 h. Increase in sample size might reduce the variation level in expression of active caspase 3 in the rat lenses.

In this work, the quasinormal mode, greybody factors, and absorption cross section of de Sitter Reissner‐Nordström black hole surrounded by quintessence field in Rastall gravity are studied. The violation of energy‐momentum conservation has a non‐linear effect on the quasinormal modes. With an increase in the black hole charge, both real parts of quasinormal modes i.e. oscillation frequency of ring‐down Gravitational Waves (GWs) and damping or decay rate of GWs increase non‐linearly. A similar observation is made for the black hole structural parameter also, however in this case the variation is almost linear. The remnant mass of a black hole depends on different physical parameters of a black hole. In the case of greybody factors also, both parameters have similar impacts are observed. With an increase in these parameters, greybody factors decrease. Moreover, the null geodesics and the impact of Rastall gravity on the light trajectory are also investigated. Our study suggests that the presence of a surrounding quintessence field may shadow the existence of black hole charges in such black hole configurations. [ABSTRACT FROM AUTHOR]

In this paper, we consider a spin 1/2 particle includes the Proton and Neutron interacting with time variable magnetic field and solve non-relativistic Schrodinger-Pauli equation. The study of occupation probability as function of time with choice of different values in coefficients of magnetic field vector and the competition between these coefficients will have interesting results in NMR spectroscopy. [ABSTRACT FROM AUTHOR]

Purposes: The aim of this study is to investigate the time evolution of active caspase 3 within first 120 h in the rat lens after in vivo exposure to subthreshold dose of UVR-B. Methods: Twenty three six-week-old female albino Sprague-Dawley rats were exposed to subthreshold dose (1 kJ/m2) of UVR-B unilaterally and sacrificed at 24, 41, 70 and 120 h after exposure. Lenses were enucleated and active caspase 3 was detected by Western Blot. The time evolution of active caspase 3 was then plotted as a function of relative mean difference in active caspase 3 between exposed and nonexposed lenses. Results: There is expression of active caspase 3 in both exposed and nonexposed lenses but there is no difference in relative mean difference in active caspase 3 between exposed and nonexposed lenses in all four postexposure groups. Conclusions: Exposure to subthreshold dose of UVR-B does not induce apoptosis in the rat lens in vivo within first 120 h though there is a non-significant increase of active caspase 3 at 120 h. Increase in sample size might reduce the variation level in expression of active caspase 3 in the rat lenses. [ABSTRACT FROM AUTHOR]

We investigated the time evolution of the symmetry of symbols constituting alphabets rooted in the Phoenician script. A diversity of quantitative measures of symmetry of graphemes appearing in Phoenician, Western Greek, Etruscan from Marsiliana, Archaic Etruscan, Neo-Etruscan, Euclidian Greek, Archaic and Classical Latin and Proto-Hebrew scripts, constituting the Phoenician script family, were calculated. The same measures were established for the Hebrew/Ashurit and English scripts. The Shannon-like measures of symmetry were computed. The Shannon diversity index was calculated. Our findings indicate that the Shannon diversity index increased with time in a monotonic way for the studied scripts. The diversity of symmetry groups inherent for addressed alphabets grows with time. We also introduced the symmetry factor of the alphabet. The symmetry factor quantifies the averaged level of symmetrization of the alphabet and the possible parsimony of graphical information necessary for the drawing of the entire set of graphemes constituting the alphabet. We found that the symmetry factor is decreased with time for the alphabets rooted in the Phoenician script. This means that the average level of symmetrization of the studied alphabet increases with time. The parsimony of graphical information necessary for writing graphemes is consequently increased with time. The values of the symmetry factor calculated for the addressed scripts are close to one another, with the pronounced exception of the Hebrew/Ashurit script. Our study supplies the arguments for the point of view, according to which the modern Hebrew/Ashurit script did not emerge from the Phoenician one.

Partial discharge (PD) in cavities can lead to a breakdown in solid insulation and, therefore, indicate the onset of aging in electrical equipment. It is necessary to investigate the activity of single- and double-cavity PD under aging conditions, which is the focus of this study. The results obtained can be useful in monitoring the condition of insulation systems. The factors (pressure, effective work function, and charge decay time constant) that influence PD behaviour under different test conditions were permutated in a PD model. The simulation results agree with measurements obtained for the same applied voltage. The model can generate PD pulse distribution shapes similar to the measured PD of single and double cavities. Both turtle-like and rabbit-ear-like phase-resolved PD (PRPD) patterns were observed during the aging process of the samples in both double and single cavities. This study concludes that the identification of the PD pattern achieved in this work for closely coupled cavities is a step towards characterizing multiple defects phenomena through PD evolution patterns.

To study the time evolution of high-energy electron radiation in circularly polarized intense laser pulses in detail, a model of the interaction between the high-energy single electron and intense laser pulses is constructed based on the Lagrangian equation and the electron energy equation. Through simulation, this article vividly displays the evolution process of radiation in the spatial, frequency and time domain. By modulating the interaction time between the laser and electron and referring to the spatial distribution image of energy, the value and direction of the maximum radiation energy per unit solid angle are calculated. In addition, in specific directions, this paper discusses the effects of interaction duration on the energy frequency distribution and the power variation pattern. The results prove that the maximum radiation energy per unit solid angle will appear when the interaction time comes to about 450 fs, which is also the boundary moment when the frequency and time spectrum no longer change obviously. Therefore, by modifying the duration of the electron–laser interaction, it is possible to produce the electron radiation with desired characteristics more precisely. [ABSTRACT FROM AUTHOR]

The conditional probability interpretation of quantum gravity has been criticized for violating the constraints of the theory and also not giving the correct expression for the propagator. We have shown that following Page’s proposal of constructing an appropriate projector for the stationary state of a closed system, we can arrive at the correct expression for the propagator by using conditional probability rule. Also, it is shown that a unitary evolution of states of a subsystem at local level may be a consequence of non-unitary projection of appropriate states at global level. [ABSTRACT FROM AUTHOR]

Surrogate models driven by sizeable datasets and scientific machine-learning methods have emerged as an attractive microstructure simulation tool with the potential to deliver predictive microstructure evolution dynamics with huge savings in computational costs. Taking 2D and 3D grain growth simulations as an example, we present a completely overhauled computational framework based on graph neural networks with not only excellent agreement to both the ground truth phase-field methods and theoretical predictions, but enhanced accuracy and efficiency compared to previous works based on convolutional neural networks. These improvements can be attributed to the graph representation, both improved predictive power and a more flexible data structure amenable to adaptive mesh refinement. As the simulated microstructures coarsen, our method can adaptively adopt remeshed grids and larger timesteps to achieve further speedup. The data-to-model pipeline with training procedures together with the source codes are provided.

We mainly study the ground state of the hydrogen atom in terms of the second kind of Legendre functions. We use a special self-adjoint transformation of the Schrödinger equation to obtain a self-adjoint operator and wave functions based on the second kind of Legendre functions without discontinuity. The projection of this wave function in terms of the complete set of the usual hydrogen atom solutions indicates the presence of a continuum. It is possible to infer that the normal hydrogen atom is weakly unstable in the presence of electromagnetic field, matter, or even quantum vacuum fluctuations due to the coupling with the continuum of the second solution. We discuss that the second solution behavior could be responsible for triggering the formation of chemical bonds. We also studied the temporal evolution of the second solution probability density, which shows an intricate structure. [ABSTRACT FROM AUTHOR]

The study of entanglement propagation in the dynamics of quantum multibody systems is an important problem in non-equilibrium physics. This paper optimizes the magnetic field to maximize the entanglement entropy and studies its influence on the entanglement propagation properties of quantum states. On the quantum Ising chain with the nearest neighbor coupling, the magnetic field obtained by variational optimization is applied to maximize the entanglement entropy of the final state and improve the entanglement growth rate in the ballistic transport region. At the same time, the entanglement entropy of the short chain can reach the entanglement saturation value of the long chain under a fixed magnetic field. When the chain length is increased, the saturation value of entanglement entropy increases, but the growth rate is almost the same. Specifically, by controlling the magnetic field, the entanglement growth rate of Heisenberg antiferromagnetic chain with only the nearest neighbor interaction can be increased to the same rate as that of the system with long-range interaction. The research in this paper reveals the ability of magnetic field to control entanglement propagation in non-equilibrium process, which can be applied to quantum control and information processing in the future. [ABSTRACT FROM AUTHOR]

The present work is aimed at assessing the change in time of flood risk as a consequence of landscape modifications. The town of San Donà di Piave (Italy) is taken as a representative case study because, as most parts of the North Italy floodplains, it was strongly urbanized and anthropized in the last several decades. As a proxy for flood risk, we use flood damage to residential buildings. The analysis is carried out at the local scale, accounting for changes to single buildings; GIS data such as high-resolution topography, technical maps, and aerial images taken over time are used to track how the landscape evolves over time, both in terms of urbanized areas and of hydraulically relevant structures (e.g., embankments). Flood hazard is determined using a physics-based, finite element hydrodynamic code that models in a coupled way the flood routing within the Piave River, the formation of levee failures, and the flooding of adjacent areas. The expected flood damage to residential buildings is estimated using an innovative method, recently proposed in the literature, which allows estimating how the damage evolves during a single flood event. The decade-scale change in the expected flood damage reveals the detrimental effect of urbanization, with flood risk growing at the pace of a fraction of urbanized areas. The within-event time evolution of the flood damage, i.e., how it progresses in the course of past or recent flood events, reflects changes in the hydrodynamic process of flooding. The general methodology used in the present work can be viewed as a promising technique to analyze the effects on the flood risk of past landscape evolution and, more importantly, a valuable tool toward an improved, well-informed, and sustainable land planning. [ABSTRACT FROM AUTHOR]

Most simulations of capacitively coupled radiofrequency cold-plasma discharges (RF-CCP) are focused on the steady state, but the initial discharge time is important for understanding the ignition process and the behavior of pulsed discharges. In this work, the time evolution of an RF-CCP Ar discharge was simulated, considering a pressure of 66.6 Pa, a distance between the electrodes of 20 mm, and RF (13.56 MHz) bias amplitudes in range 100–400 V, and the discharge evolution was observed for the first 2 μs. A 1d3v (1 dimension for particle positions and 3 dimensions for particle velocities) electrostatic particle in cell with montecarlo collisions (PIC-MCC) model was used, with separated particle weights for electrons and ions that varied with the particle density. During the simulations, the time evolution of the electron density, mean electron energy, Debye length, Debye number, and plasma frequency were observed. The spatial distribution of electric potential and the electron energy distribution function were also monitored. A transition between two regimes was observed; the first was characterized by strong oscillation of the mean electron energy and an exponential increase of the mean plasma density with time, while in the second the mean electron energy was lower, and the plasma density increased linearly. The time required for the transition between the two regimes increased as the RF amplitude was raised from 100 to 250 V, then decreased with a further increase of the RF amplitude to 300 and 350 V.

The objective of the research is to develop a new family of geopolymeric materials and to use an experimental methodology to characterize the mechanical behavior of the materials obtained by alkaline activation of metakaolin using a compound activator. The researchers also intend to study the unknown time evolution of the modulus of elasticity and the influence of the composition of the aggregates on the strength of the material. Like the material's strength, the results have a direct influence on structural safety evaluations. For the analysis of the mechanical properties of the mixtures, different types of tests were carried out: Flexural and compression tests on parallelepipeds and compression tests on cylinders were performed to assess the main strength characteristics of metakaolin-based geopolymers. Regarding the aggregate composition, the results show that the correction of the aggregate particle size line did not improve the mechanical properties. From about 400 h of curing, at ambient temperatures, the mechanical properties of the geopolymeric material are almost invariable. The highest value of the elastic modulus of elasticity occurs around 420 h, at about 18 GPa. The modulus of elasticity is independent of test load rate as per standards, and 1.7‰ strain was observed during maximum compressive stresses in the rupture tests. Also, the secant modulus values at 60% and 80% of maximum stress are within 12% of the value at 40% of maximum stress. [ABSTRACT FROM AUTHOR]

Quantum interference effects appearing in mesoscopic heterostructures have been extensively studied in static conditions over the last decades. It is interesting to examine the dynamics of these phenomena and get insight into the process of the formation of interference patterns. In this work, we analyze the time required for the formation of Fano-like resonances in a double quantum dot system. We examined the time evolution of conductance upon establishing an abrupt connection between quantum dots. Asymmetric Fano lines are characterized by the close coexistence of resonant enhancement and resonant suppression. Therefore, we pay particular attention to voltages, which in the static case, correspond to both these features. Our research shows that the analyzed resonances are characterized by two time scales: (i) the first one related to charge oscillations between subsystems and mostly governed by the interdot coupling constant and the relative position of energy levels of quantum dots, and (ii) the second one associated to the electron scattering on a continuum of states and responsible for the relaxation. We also show that the time required for achieving a static solution is different for voltages corresponding to local minima and local maxima. [ABSTRACT FROM AUTHOR]

Estimating the time evolution of a local scour hole downstream of submerged weirs can help determine the maximum scour depth and length and is essential to designing submerged weir foundations. In the current study, artificial neural networks with a backpropagation learning algorithm were used to estimate the temporal variation of scour profiles downstream of submerged weirs under clear water conditions. Physical factors, such as the flow condition, weir size, and sediment characteristics, are general scour considerations. Two sets of data combinations, namely original and non-dimensional data, were utilized in developing the backpropagation network (BPN) model. Using the data combinations and a trial-and-error method, the appropriate number of hidden neurons in the model architecture was determined. The results indicated that using non-dimensional variables as inputs in estimating the time evolution of scour holes downstream of a submerged weir is more suitable for the BPN model. Comparisons of the prediction results of the BPN model and an empirical regression formula revealed that the BPN model was more accurate and more direct in predicting the temporal variation of the local scour hole profile. In addition, sensitivity analysis showed that the dimensionless time exerted the most significant impact on the time evolution of the non-dimensional scour hole profile. • Non-dimensional datasets of parameters are better than dimensional datasets for predicting scour process with BPN model. • An accurate and direct method is developed using BPN model to predict the scour evolution downstream of submerged weirs. • The scour time is found to be the most influential parameter on scour profiles according to sensitivity analysis. [ABSTRACT FROM AUTHOR]

The security problem of IoT became more and more serious with its rapid development.Considering that the current IoT security situation awareness system lacks generality and excessively relies on expert knowledge, a IoT security situation awareness method based on improved D-S evidence theory was proposed in this paper.Fuzzy Gaussian membership function was used to calculate the vulnerability information membership matrix, which was normalized as evidence distribution matrix.The improved Topsis method was used to measure the evidence credibility.In order to fully restrain the credibility of conflicting evidence and improve the credibility of mutually supporting evidence, local credibility between two evidence was aggregated and the expected positive and negative solution vectors were improved according to the situation assessment scenario.And the weighted average method was used for vulnerability information fusion, to obtain the result of situational assessment.The result of situational awareness was fused with the time discount and high-risk vulnerability information discount evidence theory.At the same time, the IoT vulnerability information at different moments was considered comprehensively, the evidence was adaptively and dynamically weighted with the ratio information of high-risk vulnerability.The experimental results show that in the fusion of different numbers of evidence bodies and four common conflicting evidence, the improved Topsis method has higher fusion probability on credible proposition.In the aspect of situation assessment, the risk degree of current system is accurately assessed.And in the aspect of situational awareness, this discount evidence theory can predict the probability of high risk and critical risk, which is more effective than the traditional D-S evidence theory.According to this theory, a IoT security situational awareness method process was proposed, which would be used to guide engineering practice.In the future, the relationship between vulnerabilities can be considered and richer information between vulnerabilities can be extracted for vulnerability exploiting, so that the result of situation assessment is more accurate and reasonable.On the other hand, for situational awareness, game theory can be adopted in the process of dynamic game between the attacker and defender.

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We analyse the behaviour of thin composite plates whose material properties vary periodically in-plane and possess a high degree of contrast between the individual components. Starting from the equations of three-dimensional linear elasticity that describe soft inclusions embedded in a relatively stiff thin-plate matrix, we derive the corresponding asymptotically equivalent two-dimensional plate equations. Our approach is based on recent results concerning decomposition of deformations with bounded scaled symmetrised gradients. Using an operator-theoretic approach, we calculate the limit resolvent and analyse the associated limit spectrum and effective evolution equations. We obtain our results under various asymptotic relations between the size of the soft inclusions (equivalently, the period) and the plate thickness as well as under various scaling combinations between the contrast, spectrum, and time. In particular, we demonstrate significant qualitative differences between the asymptotic models obtained in different regimes. [ABSTRACT FROM AUTHOR]

Physicists are increasingly beginning to take seriously the possibility of laws outside the traditional time-evolution paradigm; yet many popular definitions of determinism are still predicated on a time-evolution picture, making them manifestly unsuited to the diverse range of research programmes in modern physics. In this article, we use a constraint-based framework to set out a generalization of determinism which does not presuppose temporal evolution, distinguishing between strong, weak and delocalised holistic determinism. We discuss some interesting consequences of these generalized notions of determinism, and we show that this approach sheds new light on the long-standing debate surrounding the nature of objective chance. [ABSTRACT FROM AUTHOR]

Scour processes caused by plunging jets are particularly important in hydraulic engineering because of the connected risk of structural failure. Therefore, many investigations have been conducted on this topic, focusing on jet‐induced scour under constant flow discharge (i.e., steady case). Yet, to the best of the authors' knowledge, no studies have analyzed the scour mechanism under variable jet discharge (i.e., unsteady case) and clear‐water conditions. Following recent theoretical advancements on scour phenomena for steady cases based on the phenomenological theory of turbulence, we address in this study the general validity of such an approach for time‐dependent (i.e., unsteady) jet inflow conditions, in non‐cohesive soils. Results show that scour evolution is consistent with that obtained for steady jet flows. In particular, they confirm the existence of two distinct phases—developing and developed—and indicate that the transition time between the two phases does not depend on the jet inflow characteristics. Once again, this study confirms that the phenomenological theory of turbulence is a valid tool for all jet‐driven scour problems. Plain Language Summary: Localized scour processes occurring in correspondence with hydraulic structures in non‐cohesive soils are often associated with plunging jets. To limit the risk of failure of the structure, the evolution of the scour geometry should be carefully predicted. In the last decades, several empirical formulae have been proposed. Despite their successful application to specific structures, these tools appear to be reliable only under limited ranges of hydraulic conditions and geometric configurations. Therefore, the development of theoretical models is welcomed. To date, the theoretical analysis of scour evolution is essentially limited to steady flow conditions. Our analysis is herein focused on jet‐driven scour processes under variable discharge and clear‐water conditions. We conducted unprecedented tests allowing us to corroborate the applicability of our recent theoretical model based on the phenomenological theory of turbulence to the unsteady case. In so doing, we show that the scour mechanism exhibits similar features under both constant and variable flow discharges and provide insights into the effect of different inflow conditions. This study conclusively shows that the adopted approach represents a general and reliable tool to address such challenging phenomena. Key Points: The scour mechanism caused by a jet impinging on a granular bed was analyzed under variable jet discharge and clear‐water conditionScour evolution is consistent with that under steady flow conditionsThe phenomenological theory of turbulence was found to be a valid tool for all jet‐driven scour problems [ABSTRACT FROM AUTHOR]

Nanoplastics, as an emerging pollutant in the environment, have the potential to adsorb various macromolecules onto the surface to form protein corona that may change the physicochemical properties and environmental fate of themselves, which deepens the uncertainty of their environmental hazards. Hence, in present study, we investigated the interaction between polystyrene nanoplastics and urease that forms protein corona over time in different conditions with atomic force microscopy, zeta potential, hydrodynamic diameter, and infrared spectroscopy. According to our results, polystyrene nanoplastics adsorbed urease and formed hard corona, changing the secondary structure of urease, and that the physicochemical properties of protein corona changed and stabilized over time. We concluded that even in a single-protein system, a dynamic process where protein molecules simultaneously adsorb onto and desorb from the surface of nanoplastics runs through the entire interaction. And we found that the formation and evolution of protein corona were governed by various interlinked factors (e.g., pH and nanoplastic surface modification types) instead of dominated by individual factor. This study aims to improve the knowledge about the formation of nanoplastic-protein corona and thus provide a reference for better evaluation of their environmental risk. • Urease formed hard corona around polystyrene nanoplastics that evolves over time. • A dynamic process runs through the interaction of nanoplastics with single-protein. • Surface modifications affects the formation of protein corona along with pH. • The secondary structure of proteins changed either reversibly or irreversibly. [ABSTRACT FROM AUTHOR]

Backward erosion piping (BEP) is a complex degradation mechanism in geotechnical flood protection infrastructure (GFPI) that is still relatively less understood, particularly when considering its time-dependent features. This manuscript presents a novel dual random lattice modeling approach for three-dimensional simulation of BEP, with a focus on its evolution over time. The key novelty of this presented framework is twofold: (1) we propose and incorporate a novel constitutive relationship for computation of time-dependent soil erosion based on the theory of rate processes, and (2) we devise an algorithm for calculation of coupled degradation of the dual lattices for accurate computation of 3-D hydraulic gradients. The constitutive relationship was developed from fundamental granular physics, and brings the potential to provide deeper fundamental physical understanding of the phenomenon. The capabilities of the modeling framework are investigated by comparison with available laboratory experiments which illustrates good agreement in the spatial advancement of piping erosion, pipe progression speeds, as well as the evolution of local gradients. To the best knowledge of the authors, the presented model is the first to be able to capture all of the aforementioned features when simulating BEP. [ABSTRACT FROM AUTHOR]

We present an overview of four challenging research areas in multiscale physics and engineering as well as four data science topics that may be developed for addressing these challenges. We focus on multiscale spatiotemporal problems in light of the importance of understanding the accompanying scientific processes and engineering ideas, where "multiscale" refers to concurrent, non-trivial and coupled models over scales separated by orders of magnitude in either space, time, energy, momenta, or any other relevant parameter. Specifically, we consider problems where the data may be obtained at various resolutions; analyzing such data and constructing coupled models led to open research questions in various applications of data science. Numeric studies are reported for one of the data science techniques discussed here for illustration, namely, on approximate Bayesian computations. [ABSTRACT FROM AUTHOR]

Wine is one of the oldest foodstuffs known in the world. It is one of the foodstuffs that is consumed not just for its benefits from nutritional point of view but also for its properties, linked with psychological impact. The local communities developed during centuries their own approaches related with wine and this way there are hundreds of different local assortments characterized by particular properties. This is the main aspect that allows us to conclude that wine is one of the most EMBEDDED food systems in Europe. Its production, presentation, certification and consumption are under national and European special regulations that provide food safety, intellectual properties rights, sustainable development and protection of local heritage even from an ethical point of view. [ABSTRACT FROM AUTHOR]

We present methods and insights for the design of CO 2 capture, transport, and storage systems for industrial facilities with a case study focus on Louisiana. Our analytical framework includes (1) evaluating the scale and concentration of capturable CO 2 emissions at individual facilities for the purpose of estimating the cost of CO 2 capture retrofits that utilize various energy supply sources to meet parasitic demands; (2) screening to identify potential CO 2 storage sites and estimate their capacities, injectivities, and costs; and (3) designing cost-minimized trucking or pipeline infrastructure connecting CO 2 capture plants with storage sites, considering existing land uses, demographics, and a variety of social and environmental justice factors. Estimated levelized costs of capture at Louisiana's 190 industrial facilities range from below $50/tCO 2 to above $500/tCO 2 , depending on facility-specific features. We identified 98 potential storage sites with storage costs ranging from $8 to $17/tCO 2 . We find that in most situations, pipelines are the least-costly mode of CO 2 transport. When industrial facilities in a region share pipelines, aggregate pipeline mileage and average transport costs are dramatically lower than without sharing. Shared pipeline networks designed to avoid disadvantaged communities require right-of-way areas compared to those for networks that transect such communities, but result in 25% higher average per-tonne transport cost.

Emergency information release during public health emergencies is a governance measure to slow down the spread of the epidemic and guide the public in scientific protection. Because of the uncertainty and life-cycle characteristics of public health emergencies, emergency information release represents the process of time dynamics. At present, it is an inevitable trend to establish a collaborative mechanism for emergency information release of public health emergencies to improve the release efficiency and respond to public demand. To determine time evolution characteristics of organizational collaboration in emergency information release, this study took the response to COVID-19 from the central government of China as an example and conducted research based on social network analysis. Based on information from COVID-19-related press conferences held by China's central government, the emergency information release collaborative networks (EIRCNs), and Emergency Organizations-Emergency Information Release Matters (EOs-EIRMs) 2-mode network were constructed. With the time evolution, the tightness, convergence, stability, and connectivity of EIRCNs in public health emergencies presented the process of lowering and then raising. At different stages, the core emergency organization (EO) nodes in EIRCNs continued to maintain a certain degree of activity. Their dynamic processes showed the characteristics of diversification rather than homogeneity. The time evolution of emergency information release matters (EIRMs) reflected the dynamic adjustment of the government's prevention and control measures and responded to the diversification of the public's understanding and protection needs during different stages of the COVID-19 pandemic. The study further examined the driving factors and implementation mechanism of the time evolution characteristics of the collaborative mode of emergency information release. The implementation of EIRMs at different stages had different resource requirements, which were usually achieved by introducing new EOs (Adding resource increment) or increasing the collaborative frequencies among EOs (Activating resource stock). In addition, further research prospects and feasibility interpretation were proposed.

The present work is aimed at assessing the change in time of flood risk as a consequence of landscape modifications. The town of San Donà di Piave (Italy) is taken as a representative case study because, as most parts of the North Italy floodplains, it was strongly urbanized and anthropized in the last several decades. As a proxy for flood risk, we use flood damage to residential buildings. The analysis is carried out at the local scale, accounting for changes to single buildings; GIS data such as high-resolution topography, technical maps, and aerial images taken over time are used to track how the landscape evolves over time, both in terms of urbanized areas and of hydraulically relevant structures (e.g., embankments). Flood hazard is determined using a physics-based, finite element hydrodynamic code that models in a coupled way the flood routing within the Piave River, the formation of levee failures, and the flooding of adjacent areas. The expected flood damage to residential buildings is estimated using an innovative method, recently proposed in the literature, which allows estimating how the damage evolves during a single flood event. The decade-scale change in the expected flood damage reveals the detrimental effect of urbanization, with flood risk growing at the pace of a fraction of urbanized areas. The within-event time evolution of the flood damage, i.e., how it progresses in the course of past or recent flood events, reflects changes in the hydrodynamic process of flooding. The general methodology used in the present work can be viewed as a promising technique to analyze the effects on the flood risk of past landscape evolution and, more importantly, a valuable tool toward an improved, well-informed, and sustainable land planning.

Open quantum systems are, in general, described by a density matrix that is evolving under transformations belonging to a dynamical semigroup. They can obey the Franke–Gorini–Kossakowski–Lindblad–Sudarshan (FGKLS) equation. We exhaustively study the case of a Hilbert space of dimension 2. First, we find final fixed states (called pointers) of an evolution of an open system, and we then obtain a general solution to the FGKLS equation and confirm that it converges to a pointer. After this, we check that the solution has physical meaning, i.e., it is Hermitian, positive and has trace equal to 1, and find a moment of time starting from which the FGKLS equation can be used—the range of applicability of the semigroup symmetry. Next, we study the behavior of a solution for a weak interaction with an environment and make a distinction between interacting and non-interacting cases. Finally, we prove that there cannot exist oscillating solutions to the FGKLS equation, which would resemble the behavior of a closed quantum system. [ABSTRACT FROM AUTHOR]

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The main scope of this study is a critical comparison of data coming from different regions in the world, where significant outbreaks of the Covid-19 pandemic took place, accounting for age differences among the considered samples. Scaling laws are derived, driving interpretations of the death toll in the analyzed clusters.

Large debris transported by flood affects scour features at bridge piers and increases the risks of structural failure. Geometric characteristics of the debris and the relative position of the pier with respect to the river bank are important parameters for the scour process. The interaction between the water flow and debris accumulation increases the shear stress, turbulence and consequently enhances the scour depth at the pier. This paper aims at analyzing such effects on scour evolution at bridge piers. To this end, two series of tests were carried out under clear water condition with different debris geometries and percentage blockage ratios. Experimental evidences showed that the pier position only influences scour evolution and equilibrium morphology for low water depths. Conversely, its effect becomes negligible for scour at bridge piers with debris accumulation and higher water depths. Useful practical relationships have been derived, with satisfactory prediction capability of the scour evolution for all the tested configurations.

The metric graph model is suggested for description of elastic vibration in a network of rods under the assumption that the rod lengths vary in time. A single rod and star-like graph are considered. Influence of the length variation law on the vibration distribution is investigated. For high-frequency length variation one observes a fast transition to high-frequency amplitude distribution.

The objective of the research is to develop a new family of geopolymeric materials and to use an experimental methodology to characterize the mechanical behavior of the materials obtained by alkaline activation of metakaolin using a compound activator. The researchers also intend to study the unknown time evolution of the modulus of elasticity and the influence of the composition of the aggregates on the strength of the material. Like the material’s strength, the results have a direct influence on structural safety evaluations. For the analysis of the mechanical properties of the mixtures, different types of tests were carried out: Flexural and compression tests on parallelepipeds and compression tests on cylinders were performed to assess the main strength characteristics of metakaolin-based geopolymers. Regarding the aggregate composition, the results show that the correction of the aggregate particle size line did not improve the mechanical properties. From about 400 h of curing, at ambient temperatures, the mechanical properties of the geopolymeric material are almost invariable. The highest value of the elastic modulus of elasticity occurs around 420 h, at about 18 GPa. The modulus of elasticity is independent of test load rate as per standards, and 1.7‰ strain was observed during maximum compressive stresses in the rupture tests. Also, the secant modulus values at 60% and 80% of maximum stress are within 12% of the value at 40% of maximum stress.

A large number of work safety accidents have exposed that accident has Domino Effect or Avalanche Effect: the chain reaction in system will be triggered when one critical node in system is disturbed, which will finally have an impact on large parts of the system. Exploring the interrelationships of elements on accident chain is very essential for studying the blocked mechanism of the accident. An improved model of dynamic of accident spreading in networks is proposed after analysing Complex Network theory and STDP mechanism. The model has the ability of independent learning of network edge weight, and finally achieves the purpose of strengthening causality and weakening non-causality. We can abstract three kinds of ideal structure networks from a large number of realistic work safety accidents: the random networks, the scale-free networks and small-word networks. This model is simulated and analysed on the three networks, respectively. The process of time dynamic evolution of accident spreading and edge weight is analysed. The simulation results are consistent with the characteristic of actual work safety accident, which indicate that the model can effectively simulate the process of accident spreading dynamics of actual work safety accident and the process of edge weights evolution. [ABSTRACT FROM AUTHOR]

A new methodology is proposed to study turbulent axisymmetric plume behaviour based on the analysis of dye forced plume images. The methodology is based on the plume geometrical information deduced from the frames and allows us to obtain measurements in all the axial and radial extensions of the plume (vertical and radial profiles) and its use in a sequence of consecutive frames allows the analysis of the time evolution of the vertical and radial measurements. The time evolution of the vertical and radial measurements allows us to study the spreading rate coefficient in detail. We define the concept of the local spreading rate (β l o c a l) and its maximum value frequently used in the studies reported in the literature and named here the classical spreading rate (β c l a s s i c). As a case study, two experiments were carried out, with two values of Atwood number (0.001 and 0.01) and a fixed source distance H o (2 cm). The results confirm the variability of the spreading rate with distance from the source (axial evolution) and show a complex time evolution depending on the z-coordinate. In addition, an asymptotic trend was observed but the asymptotic behaviour was not a constant value also depending on the z-coordinate. This methodological approach has the advantage of being noninvasive and easily exportable and requires only the recording of fluid flows (for example, volcanic plumes). Generally, it is not possible to directly control and/or measure a real fluid flow (a geophysical or pollution flow) and the only thing that can be done is its recording and analysis it, which our method allows. [Display omitted] [ABSTRACT FROM AUTHOR]

A large number of work safety accidents have exposed that accident has Domino Effect or Avalanche Effect: the chain reaction in system will be triggered when one critical node in system is disturbed, which will finally have an impact on large parts of the system. Exploring the interrelationships of elements on accident chain is very essential for studying the blocked mechanism of the accident. An improved model of dynamic of accident spreading in networks is proposed after analysing Complex Network theory and STDP mechanism. The model has the ability of independent learning of network edge weight, and finally achieves the purpose of strengthening causality and weakening non-causality. We can abstract three kinds of ideal structure networks from a large number of realistic work safety accidents: the random networks, the scale-free networks and small-word networks. This model is simulated and analysed on the three networks, respectively. The process of time dynamic evolution of accident spreading and edge weight is analysed. The simulation results are consistent with the characteristic of actual work safety accident, which indicate that the model can effectively simulate the process of accident spreading dynamics of actual work safety accident and the process of edge weights evolution. [ABSTRACT FROM AUTHOR]