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We perform molecular dynamics simulations of a binary mixture of water and trehalose with the TIP4P/Ice water model. We analyze the slow dynamics of trehalose molecules in the mildly supercooled region for concentrations of 3.66 and 18.57 wt. %. We previously studied the dynamics of water in the same mixtures. Supercooled TIP4P/Ice water solvating trehalose molecules was found to follow the Mode Coupling Theory (MCT) and to undergo a transition from a fragile to a strong behavior for both concentrations. Here, we show that also the dynamics of trehalose molecules follows the MCT and displays a fragile to strong crossover (FSC). The results show that trehalose in binary mixtures with water shares with it the dynamical behavior typical of glass forming liquids. Moreover, the FSC for trehalose structural relaxation times is found to occur at temperatures close to those previously obtained for water in the same solutions, showing that the dynamics of the solute is strongly coupled to that of the solvent. We also perform a MCT test showing that the trehalose dynamics obeys the MCT time–temperature superposition principle and that the exponents derived from the theory and the ones obtained from fitting procedure of the relaxation times are comparable, confirming that trehalose molecules in supercooled water solutions follow the MCT of glassy dynamics. Moreover, as predicted by the theory, trehalose particles have MCT parameters comparable to those of water in the same mixtures. This is an important result, given that MCT was originally formulated for monoatomic particles. [ABSTRACT FROM AUTHOR]

In this study, we discuss the observation of spin-wave interference generated by magnetic oscillators. We employ micromagnetic simulations for two coherent spin-Hall nanowire oscillators positioned nearby, horizontally or vertically. The two nanowires produce circular waves with short wavelengths on the order of 100 nm, which interfere with each other. In the horizontal configuration, the spin waves exhibit constructive and destructive fringes, indicating amplification or cancellation of the amplitudes, respectively. The synchronization of spin waves in the current geometry of the two nanowires is facilitated by the combination of dipolar fields and propagating spin waves. Additionally, the vertical alignment results in standing spin waves characterized by multiple antinodes and nodes. These observations are interpreted using a wave model that incorporates the superposition principle for each case. [ABSTRACT FROM AUTHOR]

We perform molecular dynamics simulations of TIP4P/Ice water in solution with trehalose for 3.65 and 18.57 wt. % concentrations and of bulk TIP4P/Ice water at ambient pressure, to characterize the structure and dynamics of water in a sugar aqueous solution in the supercooled region. We find here that TIP4P/Ice water in solution with trehalose molecules follows the Mode Coupling Theory and undergoes a fragile to strong transition up to the highest concentration investigated, similar to the bulk. Moreover, we perform a Mode Coupling Theory test, showing that the Time Temperature Superposition principle holds for both bulk TIP4P/Ice water and for TIP4P/Ice water in the solutions and we calculate the exponents of the theory. The direct comparison of the dynamical results for bulk water and water in the solutions shows upon cooling along the isobar a fastening of water dynamics for lower temperatures, T < 240 K. We found that the counter-intuitive behavior for the low temperature solutions can be explained with the diffusion anomaly of water leading us to the conclusion that the fastening observed below T = 240 K in water dynamics is only fictitious, due to the fact that the density of water molecules in the solutions is higher than the density of the bulk at the same temperature and pressure. This result should be taken into account in experimental investigations which are often carried out at constant pressure. [ABSTRACT FROM AUTHOR]

The lack of photons in electromagnetic spectrum region of 400–450 nm, termed cyan gap among other photoluminescence (PL) coverage issues, confines the full-visible- spectrum white light's overall capability for color rendering in part of previously studied single-component phosphors. Herein, we have mechanistically investigated that a Ce3+ incorporated silicate oxyapatite Sr 2 La 8 (SiO 4) 6 O 2 (SLS) phosphor, via a facile sol-combustion synthesis under low temperature, shows efficient cyan PL with broad full width at half maxima (fwhm, ∼90 nm) and high quantum yield (QY, ∼46.3 %) as a result of tendentious dual-site occupations and parity-allowed 4f1 ↔ 5d transitions of Ce3+, based on a combination of steady/transient-state spectroscopy and theoretical calculations. According to the principle of color superposition, the color-tunable PL, including the white emission with low coordinated color temperature (CCT) and high color rendering index (CRI), is realized by further codoping the characteristic green/red line emissions from Tb3+ and Sm3+ ions in the SLS: Ce. The low PL QY (∼32.7 %) from the monodoped Tb or Sm, due to its forbidden 4f-4f transitions, is cleverly alleviated via cascade-connected energy transfer (ET) from Ce → Tb → Sm. The direct ET from Ce → Sm is hardly occurred because of the metal-mental charge transfer (MMCT) effect. Finally, a prototype pc- w LED assembled via a remote 'capping' packaging strategy and using only the stably composition-optimized white-emitting SLS: Ce/Tb/Sm demonstrates attractive performance of the designed device (CCT 4243 K, CRI (R a) 87, CIE (0.365, 0.381), and LE 76 lm⋅W−1 under 120 mA) and the phosphor is promising for high-quality of light. The designed high-quality pc- w LED via the SLS: Ce/Tb/Sm phosphor and a UV LED chip by remote 'capping' packaging method. [Display omitted] [ABSTRACT FROM AUTHOR]

Within the manufacturing industry, hole flanging is an essential process for forming local features in sheet metal. To enhance the flanging height, the diameter of the prefabricated hole should be reduced. However, the undersized diameter of the hole may result in a crack during the flanging process. Combining the electropermanent magnet (EPM) technique with the stamping process, a composite flanging method with incremental feed is proposed to improve sheet forming performance based on the superposition principle of magnetic circuits. Through a symmetric flanging model, the thickness distribution, contour, and forming height of flanging zones are simulated, measured, and found to be reasonably consistent with related theories. The results show that the built model is suitable for investigating flanging deformation behavior. Flanging processing was performed on 304 stainless steel plates with various laser cutting predrilled hole radii. Under various increment rates, the flanging inclination angle is measured and compared through finite element method (FEM) and experiment. Furthermore, when the plate thickness ratio to the prefabricated hole diameter is 0.11, the limit circular hole flanging coefficient can reach 2.22, which is an improvement of 4.83% compared to the traditional flanging process. [ABSTRACT FROM AUTHOR]

The integration of analytical functions into machine learning-based engine models represents a significant advancement in predictive performance and operational efficiency. This paper focuses on the development of hybrid approaches to model engine combustion and temperature indices and on the synergistic effects of combining traditional analytical methods with modern machine learning techniques (such as artificial neural networks) to enhance the accuracy and robustness of such models. The main innovative contribution of this paper is the integration of analytical functions to improve the extrapolation capabilities of the data-driven models. In this work, it is demonstrated that the integrated models achieve superior predictive accuracy and generalization performance across dynamic engine operating conditions, with respect to purely neural network-based models. Furthermore, the analytical corrective functions force the output of the complete model to follow a physical trend and to assume consistent values also outside the domain of values assumed by the input features during the training procedure of the neural networks. This study highlights the potential of this integrative approach based on the implementation of the effects superposition principle. Such an approach also allows us to solve one of the intrinsic issues of data-driven modeling, without increasing the complexity of the training data's collection and pre-processing. [ABSTRACT FROM AUTHOR]

The stratigraphic principle of superposition assumes that sediments at surface are youngest. And yet, patches of older preserved landscapes continue to be identified in the regions formerly covered by the Laurentide Ice Sheet. Two gravel pits, at the edge of the western Hudson Bay Lowland near the geographic centre of the North American Ice Sheet Complex, reveal additional patches where older glacial and nonglacial sediment is preserved. These sites expose 1–4 m of a darker, highly overconsolidated, clayier till, and 0–2 m of a lighter, less consolidated, sandier till over glaciofluvial and post-glacial gravels and sands; the waning stages of deposition occurred at 214 ± 22 ka (1σ minimum age model quartz grain optical age estimates, n = 2). This was during the latter end of the cool Marine Isotope Stage (MIS) 7-d (within 1σ range) or near the end of MIS-8 (within 2σ range). Next followed a warmer period similar to, or warmer than, present day with higher precipitation; inferred from pollen and macrofossils deposited in nonglacial low-energy floodplain or pond sediments. Our study highlights the need to accurately date Quaternary sediments, given that the shallowest nonglacial sediments at both gravel pits were deposited during an old (MIS 7) interglacial; there is likely no record of the youngest interglacial (MIS 5). Preservation of older sediment also means that in Quaternary stratigraphy, disjoint regional nonglacial "organic marker beds" should not automatically be considered correlative. Identification of similar "old" patches, together with till stratigraphy and composition, is essential to accurately model glacial sediment transport over time. [ABSTRACT FROM AUTHOR]

In order to bridge the gap between the effects of superposition of unequal amplitude waves on superimposed waves, this paper investigates the effects of variable amplitude superimposed waves on piezoelectric actuators. The generation mechanism of traveling waves is explored from the principle of superposition of waves. A mathematical model of the piezoelectric beam is established based on the Euler-Bernoulli beam theory and the Lagrange equation. It is the first time that the effects of variable amplitude superimposed waves on motion performance are investigated from both theoretical and experimental perspectives. The effects of variable amplitude waves on kinematic performance are tested by changing different excitation frequencies, different positions and different loadings. The relationship between the amplitude ratio A and the motion performance is given. It is shown that there is an approximately linear negative correlation between the amplitude ratio and the motion performance when the amplitude ratio A = 1–2.4. This study provides a new idea for the generation of traveling waves and provides a reference for the design and application of piezoelectric actuators. [ABSTRACT FROM AUTHOR]

Lactose hydrolyzed skim milk powder has the potential to become a staple value-added ingredient in snack and frozen foods because 70% of the population suffers from lactose intolerance. However, the flow behavior of lactose hydrolyzed skim milk concentrates and their resulting products need to be understood. The aim of this study was to compare two rheological modeling methods and determine which method is best for predicting rheological behavior in lactose hydrolyzed and unhydrolyzed skim milk concentrates and reconstituted powder samples. The two methods compared are the combined temperature-concentration multiple-linear regression model and the shear rate-temperature-concentration superposition principle master curve model. Prior to fitting the data to the two models, the effect of temperature was determined via the Arrhenius relationship and the effect of concentration was determined via the Exponential relationship. The combined temperature-concentration method resulted in a single logarithmic model for each concentrate type which yields the consistency coefficient at any temperature and concentration input. The master curve method resulted in a single Power law type model for each concentrate type that describes the overall rheological behavior of the samples. When the predicted consistency coefficients from each method were compared to the raw data, both the master curve (r = 0.973, P < 0.0001) and the combined (r = 0.940, P < 0.0001) methods showed a strong correlation to the raw data. When the results were examined by concentrate type, the master curve model had a stronger fit (P < 0.01) for the reconstituted samples compared to the combined model which did not show a statistically significant correlation to the raw data (P < 0.075). The results of this study indicate that the master curve method is superior for predicting the rheological behavior of concentrated milk samples prepared from varying methods within our tested ranges. [ABSTRACT FROM AUTHOR]

The converse flexoelectric effect can be applied to control thin-shell structures. In this paper, the vibration control of a conical shell with multiple flexoelectric actuators is studied. In order to investigate the actuation performance of the flexoelectric patch, this study analyzes the electric field gradient, modal forces, and displacement of a conical shell driven by the flexoelectric patch and their relationships with the design parameters. In the physical model, the AFM probe is positioned on the upper surface of the flexoelectric patch to create a high-intensity non-uniform electric field within the flexoelectric actuator. In turn, generates internal stress in the flexoelectric actuator patch through the converse flexoelectric effect. The case study shows that the high-intensity non-uniform electric field generated by the AFM probe has nearly zero contribution to the electric field in areas far from the contact point. As a result, the stress generated by the converse flexoelectric effect primarily concentrates near the AFM probe, with the size and shape of the flexoelectric patches having minimal influence on the actuation. Based on the assumption of small deformation and linear displacement, considering the vibration control of multiple flexoelectric actuators on the truncated conical shell, the lateral displacement results controlled by multiple flexoelectric actuators can be calculated by the superposition principle. When multiple flexoelectric actuators work together, the same flexoelectric actuator in different positions may induce opposite lateral displacements at a specific point on the surface of the truncated conical shell. This can result in the cancellation of vibrational displacements produced by the flexoelectric actuators. Approximate optimal distribution positions for the multi-channel flexoelectric actuators were determined through experimental simulations. In this study, the superior vibration suppression capabilities of multi-channel flexoelectric actuators are highlighted through a comparative analysis with single-channel configurations, demonstrating their effectiveness in controlling complex vibration modes in conical shell structures. [ABSTRACT FROM AUTHOR]

In this work, numerous rogue wave solution strategy (MRWSS) agreeing to the Hirota bilinear hypothesis is utilized. The said strategy to build different soliton wave solutions for the generalized Hirota-Satsuma-Ito (GHSI) condition is considered. These numerous soliton wave solutions incorporate first-order, second-order, third-order, and fourth-order waves solutions and so on, which are all depending on the starting theory of chosen capacities. For the lump solution with one most extreme or least esteem, the properties of the Hessian lattice are examined. Besides, the arrangements are contained the lump-two kink arrangements, cross-kink wave arrangements, periodic wave arrangements, and periodic-kink wave arrangements. The various classes of arrangements are gotten. We make utilize of the direct superposition procedure to find out N-soliton wave arrangements to the said condition. The appropriateness and viability of the obtained arrangements is detailed through the reenactment comes about within the shape of 3-D, density, and 2-D charts. The gotten comes about in this work are anticipated to open modern viewpoints for the traveling wave theory. [ABSTRACT FROM AUTHOR]

The objective of this research is to address the rut problems in asphalt pavements and to resist the permanent plastic deformation with the increasing heavy traffic loads. In this paper, a new type materials of high modulus asphalt was developed by incorporating styrene–butadiene–styrene (SBS) and zinc oxide nanoparticles (nano ZnO) with an (EME)-type high modulus modifier, guided by the synergistic effects and the preparation methods of High-speed shear. The basic road performance, mechanical response and thermal stability of the new high modulus asphalt materials were analysed through basic physical indicator tests, dynamic shear rheometer tests, thermogravimetric analysis (TGA), the time–temperature superposition principle, the Refutas model, and the Christensen-Andersen-Marasteanu model. The optimal results demonstrate that the optimal blend ratio of the developed asphalt is 12% EME/8% SBS/1.5% ZnO. Under this composition, the road performance indicator values of softening point, penetration and ductility of the modified asphalt met the standard requirements. The dynamic shear rheometer tests demonstrates that the inclusion of SBS and nano ZnO considerably enhanced the shear resistance and recovery deformation capacity of EME, effectively improving the high-temperature deformation resistance of asphalt. Furthermore,the Refutas and the Christensen-Andersen-Marasteanu model fitting results showed that adding SBS and nano ZnO considerably improved the temperature sensitivity of the EME types high modulus modified asphalt and exhibiting low frequency sensitivity. Compared to PR Module-type high modulus modifier(PRM),TGA reveals that the maximum thermal weight loss of EME-SBS-ZnO decreased by 3.5441%, indicating better thermal stability and the major character of SBS,EME and asphalt is physical reaction. Moreover, EME-nano ZnO-SBS high modulus asphalt at 64 °C shows Jnr-diff = 9.5% and passes the "E" extreme traffic grade. Additionally, its cost is 4.67% lower than that of the PRM high modulus modified asphalt, presenting considerable economic benefits. [ABSTRACT FROM AUTHOR]

Vegetation communities can drastically influence the hydrodynamic characteristics of the overland flow, change the overland flow resistance mechanism, and regulate soil erosion. To investigate the effect of grass-shrub vegetation and litter combinations on overland flow resistance, simulated rainfall experiments were carried out. The experiments involved a 15° gradient slope, five rainfall intensities (I = 60–120 mm h−1), five grass-shrub coverages (Cgs), and six litter volumes (Cl). The results showed that the mean values of form resistance under Cgs = 15%–75% ranged from 0.195 to 1.775, and the mean values of form resistance under Cl = 5–25 g m−2 ranged from 0.609 to 2.160. The form resistance of grass-shrub slopes with the addition of litter was 1.82–12.47 times higher than that under a single grass-shrub cover. The order of magnitude of the factors influencing the slope form resistance coefficients of the grass-shrub + litter was Cl > Cgs > Cl × Cgs > I. With varying vegetation kinds and coverage rates, I had diverse effects on form resistance. The resistance superposition principle does not hold under combined vegetation cover conditions. The degree of difference (Δ f form ) in form resistance was inversely proportional to I and directly proportional to Cl. Through dimensional and multiple nonlinear regression analyses, a general model for calculating form resistance was established (Adj. R2 = 0.99, NSE = 0.97). Theoretically, the results of this study can be used to evaluate soil and water conservation during vegetation community succession and restoration. [ABSTRACT FROM AUTHOR]

In this article, the propagation and scattering of Rayleigh wave from an interfacial crack in a bilayer structure, a viscoelastic waveguide layer attached to a piezoelectric substrate, have been examined. The Principle of Superposition is used to formulate the problem. The Fourier transform method and stiffness matrix formulation have been used to arrive at singular integral equations. These singular integral equations are then reduced to a system of linear algebraic equations by applying the Gauss-Jacobi quadrature technique. A parametric study has been examined for phase velocity, attenuation, and dynamic stress intensity factor of mode-I and mode-II at both crack-tip. [ABSTRACT FROM AUTHOR]

The paper presents the design of a Customised Homocentric Fresnel Collector (CHFC) based on the principle of superposition and the longest wavelength of the visible spectrum. A bottom-to-top approach is proposed that uses an individually designed homocentric prism based on visible light at a wavelength of 740 nm. The homocentric prism of the CHFC follows a uniform height method with varying pitch. An area focus is achieved on the plastic optical fibre (POF) bundle inlet without employing any secondary optical element. The CHFC achieves a uniform distribution of concentrated visible spectrum radiation from the Sun with a significant reduction in the hotspot problem. Comparison of the CHFC versus a mid-wavelength-based Fresnel lens shows that the CHFC delivers 9.24% more visible spectrum radiation on the POF bundle inlet. The simulated optical efficiency of the CHFC is 90.6%. Numerical analysis of a CHFC-based daylighting system shows that 331 lm (efficiency of 39.4%) can be delivered via a 10 m long fibre bundle made up of 32 POF each of 1 mm diameter. Experimental observations demonstrated that the maximum temperature recorded on the POF bundle entrance is 56.8°C during peak direct normal illuminance conditions. Note that the spectral distribution of the radiation emerging from the POF differs from the incident sunlight spectrum because of the transmission characteristics of the optical components used in the CHFC testbed. [ABSTRACT FROM AUTHOR]

The dynamic response of a double-layered circular region under anti-plane linear loads is investigated using the complex function method. The scattering wave functions for each layer are provided, and the total wave field functions for each layer are formulated through the superposition principle. By establishing an infinite linear equation system with unknown coefficients based on the boundary conditions, finite term truncation is performed to obtain the dynamic stress concentration coefficient of the circular hole defect. Furthermore, a specific example is presented to discuss both the validity of the theory and numerical results regarding this factor. [ABSTRACT FROM AUTHOR]

The objective of this study is to investigate the stability of plane strain rectangular tunnels under the effects of soil cohesion, surcharge loading, and soil unit weight. The novelty of the study is to extend Terzaghi's bearing capacity equation approach for determining three tunnel stability factors (Nc, Ns, and Nγ) that can be used to evaluate a tunnel's stability. These stability factors, functions of the coverdepth ratio (H/D), width-to-height ratio (B/D), and drained friction angle (ϕ), are employed in conjunction with the principle of superposition to assess the overall stability of a tunnel. To achieve this objective, the study employs finite-element limit analysis (FELA) with adaptive meshing techniques to ensure accurate calculations and address any disparities between the upper bound and lower bound solutions. The analysis elucidates the failure mechanisms of the tunnel and validates the results by comparing them with prior research. In addition, closed-form equations are developed to facilitate the calculation of these stability factors using machine learning methods, consisting of artificial neural network and support vector machine. The research is expected to provide valuable insights into the stability of rectangular tunnels, particularly in scenarios involving soil cohesion, surcharge loading, and varying soil unit weights. The combination of traditional geotechnical principles with modern FELA numerical methods and machine learning predictive models promises to offer a comprehensive and practical approach for tunnel stability analysis. [ABSTRACT FROM AUTHOR]

Optical computing harnesses the speed of light to perform vector-matrix operations efficiently. It leverages interference, a cornerstone of quantum computing algorithms, to enable parallel computations. In this work, we interweave quantum computing with classical structured light by formulating the process of photonic matrix multiplication using quantum mechanical principles such as state superposition and subsequently demonstrate a well-known algorithm, namely, Deutsch–Jozsa's algorithm. This is accomplished by elucidating the inherent tensor product structure within the Cartesian transverse degrees of freedom of light, which is the main resource for optical vector-matrix multiplication. To this end, we establish a discrete basis using localized Gaussian modes arranged in a lattice formation and demonstrate the operation of a Hadamard gate. Leveraging the reprogrammable and digital capabilities of spatial light modulators, coupled with Fourier transforms by lenses, our approach proves adaptable to various algorithms. Therefore, our work advances the use of structured light for quantum information processing. [ABSTRACT FROM AUTHOR]

Quantum computers accelerate many algorithms based on the superposition principle of quantum mechanics. The Grover algorithm provides significant performance to malicious users attacking symmetric key systems. Since the performance of attacks using quantum computers depends on the efficiency of the quantum circuit of the encryption algorithms, research research on the implementation of quantum circuits is essential. This paper presents a new framework to construct quantum circuits of substitution boxes (S-boxes) using system modeling. We model the quantum circuits of S-boxes using two layers: Toffoli and linear layers. We generate vector spaces based on the values of qubits used in the linear layers and apply them to find quantum circuits. The framework finds the circuit by matching elements of vector spaces generated from the input and output of a given S-box, using the forward search or the meet-in-the-middle strategy. We developed a tool to apply this framework to 4-bit S-boxes. While the 4-bit S-box quantum circuit construction tool LIGHTER-R only finds circuits that can be implemented with four qubits, the proposed tool achieves the circuits with five qubits. The proposed tool can find quantum circuits of 4-bit odd permutations based on the controlled NOT, NOT, and Toffoli gates, whereas LIGHTER-R is unable to perform this task in the same environment. We expect this technique to become a critical step toward optimizing S-box quantum circuits. [ABSTRACT FROM AUTHOR]

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This study demonstrates a novel, single‐step, and low‐energy ultrasonic approach to fabricate lightweight, high‐performance flax fiber‐reinforced composites enhanced by nanotitanium dioxide coating and fly ash hollow cenospheres. This innovative approach leads to a remarkable 23% weight reduction compared with conventional composites, making it ideal for the applications demanding both lightweight and superior mechanical properties. Through dynamic mechanical testing, it is found that the composites' viscoelastic behavior, including storage modulus and damping factor, is significantly influenced by both frequency and temperature. By applying time–temperature superposition principles, the composite's dynamic properties are comprehensively characterized across a wider frequency range. A modified fractional calculus Huet–Sayegh model accurately captures the observed viscoelastic behavior. The combined effect of nanotitanium dioxide coating, which strengthens the fiber–matrix interface, and the inclusion of rigid fly ash hollow cenospheres results in significant improvements in both storage modulus (10% increase at room temperature) and peak loss factor (80% increase) compared with uncoated flax fiber‐reinforced composites. The nanocoating and cenospheres' rigid shells contribute to enhanced stiffness, while the cenospheres' hollow structure provides efficient energy dissipation mechanisms, leading to an improved damping performance. This ultrasonic approach offers a promising and sustainable method for synthesizing natural fiber nanocomposites with superior viscoelastic properties. [ABSTRACT FROM AUTHOR]

The paper provides new experimental evidence for vulnerable artifacts on the dependence of failure strain on the loading rate corresponding to typical environmental loads lasting between hours and months. Animal glue-based ground was chosen for this study as an easily available, hygroscopic and brittle material as well as due to its abundance in collections and its relevance when discussing the risk of mechanical damage to objects. Gesso specimens were tested using dynamic mechanical analysis and tensile testing at different frequencies, under a variety of loading rates and temperatures. The time-temperature superposition principle was used to predict the material response to slow deformations (lasting hours to months) that are otherwise inaccessible on laboratory timescales. The results demonstrate that brittle materials such as animal glue-based grounds do not benefit from longer cycles of applied loads as failure strain is not time-dependent within the investigated timescale. [ABSTRACT FROM AUTHOR]

Principle of quantum superposition permits a photon to interfere with itself. As per the principle of causality, a photon must pass through the double-slit prior to its detection on the screen to exhibit interference. In this paper, a double-slit quantum interference experiment with reversible detection of Einstein–Podolsky–Rosen quantum entangled photons is presented. Where a photon is first detected on a screen without passing through a double-slit, while the second photon is propagating towards the double-slit. A detection event on the screen cannot affect the second photon with any signal propagating at the speed of light, even after its passage through the double-slit. After the detection of the first photon on the screen, the second photon is either passed through the double-slit or diverted towards a stationary photon detector. Therefore, the question of whether the first photon carries the which-path information of the second photon in the double-slit is eliminated. No single photon interference is exhibited by the second photon, even if another screen is placed after the double-slit. [ABSTRACT FROM AUTHOR]

This study focuses on the failure analysis of a hypocycloid-type crack within a thermo-elastic material. Employing the conformal mapping method, analytical continuation theorem, and principle of superposition, the explicit general solution for stress intensity factors (SIFs) associated with an arbitrary-edged hypocycloid-type crack is determined analytically under the influence of remote homogeneous heat flux and mechanical load. The superposition method combines stress functions and SIFs for two distinct loading conditions. The outcomes of the normalized SIFs are affected by the magnitude and orientation of the heat flux and mechanical load. A full-field stress distribution is provided to account for variations in SIFs. Certain combinations of loads lead to maximum SIF values, rendering the system highly vulnerable to damage, while two specific scenarios inhibit crack propagation, thereby reducing the risk of structural failure. [ABSTRACT FROM AUTHOR]

In the existing analytical solutions for tunnels, the tectonic stress boundary conditions caused by faults are often overlooked. This study presents an analytical solution that considers the tectonic stress field in the surrounding rock of a near-fault tunnel, taking into account the crack model of faults. The tectonic stress field is derived, and the regularized boundary conditions are obtained to determine the principal stress states and the range of field. The stress constants of the boundary conditions are calculated using the superposition principle. To effectively solve the analytical functions, the Riemann–Hilbert method is adopted, incorporating the tectonic stress boundary condition. Subsequently, an analytical solution for the stress concentration near the tunnel is obtained and validated through numerical simulations. The influence of fault angles and distances on the degree of stress concentration around the tunnel is analyzed. The results reveal that the stress concentration without faults follows a similar trend as the scaling rate of the tunnel. However, due to the influence of tectonic stress, the stress concentration degree in different regions exhibits asynchronous variations with increasing fault dips. Moreover, the stress concentration degree decreases with increasing distances in each region of the tunnel boundary. Highlights: This study provides a general solution to the stress field of a near-fault tunnel. The new understanding should help to improve predictions of the effect of tectonic stress boundary conditions. A crack calculation model is established for analyzing the tectonic stress field, which is the potential function of the coordinates. The tectonic stress boundary conditions of the tunnel are established based on the principal stress state of the equivalent disturbance stress field. The constants of the tectonic stress boundary condition can be superimposed with the in situ stress to obtain the complete stress boundary condition. The Riemann–Hilbert method is applied to solve the analytical function effectively. The stress field can be obtained to describe the mechanical behavior of the tunnel near fault accordingly. This thesis has provided a deeper insight into the degree of stress concentration K in the near-fault tunnel. K is influenced by the scaling rate of the tunnel type, as well as the dip and distance of the fault. [ABSTRACT FROM AUTHOR]

This paper presents robust input shaping commands with first-order actuators utilizing a classical robust input shaper for practical applications in input shaping technology. An ideal input shaping command can deviate due to actuator dynamics so that the modified command has a detrimental effect on the performance of oscillation reduction in feedforward control applications. A zero-vibration-derivative (ZVDF) shaper with first-order actuators is analytically proposed using a phasor–vector approach, an exponential function for the approximation of the dynamic response of first-order actuators and the usage of the ZVD shaper. In addition, an equivalent transformation is utilized based on the superposition principle for the convenient inclusion of first-order actuator dynamics and is applied to the individual segment input command. The residual deflection and robustness of the proposed robust input shaping commands are numerically evaluated and compared with those of a conventional ZVD shaper with respect to the parameter uncertainties of flexible systems and actuators. The robust input shaping commands that are possible with first-order actuators are experimentally validated, presenting a better robustness and residual deflection reduction performance than the classical ZVD shaper on a mini bridge crane. [ABSTRACT FROM AUTHOR]

The L-shaped partially encased steel–concrete composite (PEC) stub column, composed of profile steel, concrete, and transverse links, tends to occupy less space than the rectangle-shaped PEC column when used as side or corner columns. In this study, an axial compression test involving three L-shaped PEC stub columns was conducted to investigate the influence of critical factors on axial compression performance. The test results indicated that the axial compression capacity can be effectively enhanced with an increase in material strength. Furthermore, finite element (FE) analysis was carried out with parameters such as material strength, steel thickness, transverse link spacing, transverse link diameter, transverse link distribution, and longitudinal rebar diameter. The results revealed that the primary failure modes of L-shaped PEC columns were concrete spalling and local buckling of the flange. Additionally, it was found that the increase in steel strength, steel thickness, and transverse link diameter, as well as the decrease in transverse link spacing, significantly improved the axial compression capacity and concrete confinement effect. However, an increase in concrete strength diminished the concrete confinement effect. Additionally, the accuracy of the axial compression capacity calculation methods in the Eurocode 4 and T/CECS719-2010 specifications for L-shaped PEC stub columns was verified. Finally, a calculation method based on the superposition principle incorporating the concrete confinement effect was proposed, and validated by comparing with experimental and FE results. Overall, this study could provide a theoretical basis for the engineering application of L-shaped PEC columns. [ABSTRACT FROM AUTHOR]

Wheel polygons pose a threat to the safety of train operations due to wheel fatigue, necessitating online identification. The online identification of wheel polygons predominantly relies on the axle box vertical nx (n-multiple integer of axle rotation frequency) signals generated by wheel polygons. The low-order vertical nx signals are easy coupling to other faults like axle cracks, leading to errors in wheel polygon identification. A signal decoupling method is crucial for removing the crack components from the vertical nx signal to obtain more accurate identification results for low-order wheel polygons. Employing principles of signal superposition for different faults, this article proposes a method to decouple the wheel polygon nx signal from the vertical nx signal by subtracting the crack-related portion. This method has been validated through an ABAQUS + SIMPACK online rigid-flexible coupling model, indicating that it significantly improves the accuracy of wheel polygon identification. The 1x amplitude of the decoupled signal decreased by 60.78%, and the 2x amplitude decreased by 55.79%. [ABSTRACT FROM AUTHOR]

Fracture geometries and drainage radius are essential parameters for developing a reasonable development plan for a single fractured well. However, owing to fracture hits, the complex fracture geometries bring challenges for parameter estimations. This paper establishes a well testing based model for a finite-conductivity fractured vertical well in radial composite reservoirs with dynamic supply and fracture networks. Based on the successive steady-state method, the point source function, pressure superposition principle, and boundary element method are used to solve the reservoir model, and the methods of discrete fracture and pressure superposition are used to solve the fracture model. By introducing the rate-normalized pseudopressure and material balance time, the variable fluid flux is equivalent to the constant fluid flux. The drainage radius value and fracture geometries are solved by fitting the log-log curves of pressure response, and case studies are performed. The results show that the drainage radius increases with the increase of production time and finally tends to a specific value, and it has an excellent exponential relationship with time. Also, the fracture geometries of the typical well are multiple-radial fracture networks. Through the study of dynamic drainage radius, the controlled reserves of single wells in unconventional gas reservoirs can be better determined, and it can also provide a theoretical basis for fracture evaluation, productivity prediction, and enhanced recovery study of the same type of tight gas reservoir. [ABSTRACT FROM AUTHOR]

Elastomer O-ring seals are used in many technical applications and their requirements are becoming increasingly challenging for high-pressure applications like hydrogen storage systems. We analyze the performance of such seals at low temperatures and highlight the essential effects of primary leakage. Linear viscoelastic material modeling is described and defined with the help of Dynamic Mechanical Thermal Analysis (DMTA), Time-Temperature Superposition Principle (TTSP), and the shift function of Williams-Landel-Ferry (WLF) by assuming thermo-rheological simple material behavior. Numerical calculations and experimental validation are done for strain-rate dependent uniaxial tensile tests, Temperature Retraction (TR), Compression Set (CS), and specific leakage tests with O-rings. Thanks to Finite Element Analysis (FEA) it is possible to identify the most significant influences on the sealing tightness. Thermal shrinkage and the increasingly limited recovery of elastomer O-rings are mainly responsible for primary leakage at low temperatures and can be enforced by time-temperature dependent stress relaxation and manufacturing tolerances. • The elastomer material 80FVMQ 567 was characterized via several material tests. • Linear viscoelastic material modeling was described in detail (WLF, TTSP, Prony) and implemented in the simulation. • Finite element simulations were validated with key O-Ring experiments at different temperatures. • The generation of primary leakage could be shown with numerical analyses and experiments. • The essential effects of primary leakage were identified and segregated with Finite Element Analyses and experiments. [ABSTRACT FROM AUTHOR]

In this study, the Time-Temperature-Crystallinity Superposition Principle (TTCSP) was applied to determine the viscoelastic behavior of Thermo-rheological Complex Materials (TCM), specifically Carbon fibre/Poly-Ether-Ketone-Ketone (CF/PEKK) composites. The study investigated the effects of various parameters on the viscoelastic behavior of the composites, such as the degree of crystallinity after different melting temperatures, relaxation, and crystallization times. The TTCSP was utilized on the relaxation data to generate great-grand master curves for the degree of crystallinity for different laminate lay-ups. Hot press forming was employed to manufacture samples under different processing conditions, including various melting and cold crystallization temperatures. Differential Scanning Calorimetry (DSC) was employed to calculate the degree of crystallinity of CF/PEKK composites, while the Dynamic Mechanical Analyzer (DMA) was used to obtain the relaxation data. The generated great-grand master curves proved effective in predicting the relaxation behavior of the composites consolidated using single and double hold cycles at different melting temperatures and crystallization times, respectively. The great-grand master curves presented in this study can serve as valuable tool to calibrate key viscoelastic and/or thermo-viscoelastic material models for aerospace-grade CF/PEKK composites. These models are crucial for simulations aimed at predicting residual stresses and process-induced deformations during the thermoforming process. [ABSTRACT FROM AUTHOR]

The rheological properties of a polyamide (PA) resin with low crystallinity were modified by melt-mixing it with a small amount of an alternative α-olefin–maleic anhydride copolymer as a reactive compound. Because PA has a low melting point, rheological characterization was performed over a wide temperature range. Owing to the reaction between PA and the alternative α-olefin–maleic anhydride copolymer, the blend sample behaved as a long-chain branched polymer in the molten state. The thermo-rheological complexity was obvious owing to large flow activation energy values in the low modulus region, i.e., the rheological time–temperature superposition principle was not applicable. The primary normal stress difference under steady shear was greatly increased in the wide shear rate range, leading to a large swell ratio at the capillary extrusion. Furthermore, strain hardening in the transient elongational viscosity, which is responsible for favorable processability, was clear. Because this is a simple modification method, it will be widely employed to modify the rheological properties of various polyamide resins. [ABSTRACT FROM AUTHOR]

Due to high energy density, clean combustion products and abundant resources, natural gas hydrates (NGHs) have been regarded as an important clean energy source with the potential for large-scale development and utilization. However, pilot tests in NGHs show that their production rates are far below commercial needs. Multilateral well technology may lead to a solution to this problem because it can dramatically expand the drainage area of production wells. This paper presents the practical rate transient analysis for multilateral horizontal wells in NGHs. In developing solution to the diffusivity equation of multilateral horizontal wells in NGHs, the superposition principle and reciprocity are applied. We wrote the governing equation in cylindrical coordinates to describe the NGH flow process. We used the moving boundaries and dissociation coefficients to model the solid-to-gas transition process in hydrates. To obtain solutions for flow in hydrate reservoirs, we used Laplace transforms and the Stehfest numerical inversion method. Superposition principle and Gaussian elimination are applied to obtain the desired solution for multilateral horizontal wells. We validated our proposed model with a commercial numerical simulator. By performing sensitivity analyses, effects on production behavior of the number of branches, dissociation coefficient, radius of the region with dissociated hydrate, and dispersion ratio are determined. A synthetic case study is conducted to show the typical production behaviors. [ABSTRACT FROM AUTHOR]

This paper considered the groundwater head fluctuation induced by tide and pumping in the coastal multi-layered aquifer system. The multi-layered aquifer system comprises an unconfined aquifer, an upper confined aquifer, and a lower confined aquifer. An aquiclude exists between each two aquifers. All the layers terminate at the coastline. The new analytical solutions describing groundwater head variation in the coastal multi-confined aquifer system are derived. Superposition principle and image methods are used for the derivation of the analytical solutions. Analytical solutions of different situations of without considering pumping, of without considering tidal effect, and of N-layered confined aquifers are also derived. The impacts of the parameters of the initial phase shift of tide, pumping rate, position of the pumping well, storage coefficient, and transmissivity on the groundwater head fluctuation are discussed. The analytical solutions are applied with application examples in fitting field observations and parameter estimations. The estimated values of the hydraulic conductivities in the upper and lower confined aquifers are within the range of the values obtained from the field experiments. The fitted results of the analytical solutions capture the main characteristics of groundwater head fluctuation affected by the tide and groundwater pumping. The study of groundwater head fluctuation in the coastal zone is helpful to understand the mechanism of seawater intrusion under the influence of tide and groundwater pumping. [ABSTRACT FROM AUTHOR]

To enhance the functionality of a constant-torque flexure hinge (CTFH), a bidirectional double-arc constant-torque flexure hinge (BD-CTFH) is proposed. The BD-CTFH exhibits characteristics such as a bidirectional constant-torque output and sufficient proportion of constant-torque output. The primary objective of this study is to establish a pseudo-rigid-body model of the BD-CTFH (BD-PRBM) to accurately determine the constant-torque output performance. In addition, a comprehensive analysis of the torque-angle characteristics of the BD-CTFH is conducted through finite element analysis (FEA), theoretical calculations, and experimental testing. The results indicate that the discrepancy between the theoretical and FEA results is within 2 %, confirming the accuracy of the BD-PRBM. Moreover, the average deviation between the experimental and theoretical results is within 5 %, further validating its accuracy. Finally, through preloading tests, it is verified that the BD-CTFH exhibits a constant-torque region of 12–36° (and -12–-36°). • The novel flexure hinge (BD-CTFH) incorporates double-arc segments for the first time. • The BD-CTFH has the characteristic of bidirectional constant-torque output. • The PRBM of BD-CTFH (BD-PRBM) is established. • Preload of BD-CTFH is carried out to enlarge the proportion of constant-torque. [ABSTRACT FROM AUTHOR]

It is common to use very high electric fields (E) to defibrillate hearts, which can damage cardiomyocytes, showing the importance of developing methods that can decrease the E applied in defibrillation protocols. We used COMSOL Multiphysics software to model, simulate, and analyze the application of an E in an isolated heart with monodirectional and multidirectional stimuli, using 2 pairs of electrodes and the superposition principle as a way to decrease the E applied and reduce the required number of stimulation electrodes. When applying an E of 3 V/cm in the 0°, 30°, and 60° directions, individually in the stimulation chamber, E was equal to 3.2 V/cm and its phases were equal to 0°, 30°, and 60°, respectively, validating the superposition principle. We observed a reduction up to 31.8% in | E | when applying a multidirectional stimulus when comparing to the monodirectional stimulus, in order to stimulate the same area of the heart. For the same amount of stimuli directions, we obtained up to 11.7% reduction of | E |, just by modifying the directions of the applied stimuli. In the simulation developed in this work, the superposition principle was validated in a stimulation chamber. For the same stimulated area, the multidirectional E has been always lower than the monodirectional. We observed that, in order to decrease the intensity of E, both the number of applied stimuli and their directions were relevant issues. [ABSTRACT FROM AUTHOR]

This study emphasizes the influential role of rheology in decoding the viscoelastic properties of pressure-sensitive adhesives (PSAs) vital to predicting key application features such as shear, tack, and peel, depending on the flow characteristics of PSAs during bonding and debonding processes. By applying the principle of time–temperature superposition (TTS), we extend the scope of our frequency analysis, surpassing the technical constraints of the available apparatus. Our exploration aims to uncover the general correlations between PSAs' viscoelastic properties and their performance in end-use applications. Initially, the adhesive performance and viscoelastic properties of a UV-crosslinkable styrene-butadiene-styrene (SBS) model adhesive prior and subsequent to UV irradiation were examined. The subsequent crosslinking reaction increased cohesive strength and heat resistance, although tack and peel strength observed a substantial decline. We successfully demonstrated these effects by logging the viscoelastic properties, specifically the storage modulus G′ at lower frequencies, which mirrors the shear strength at higher temperatures and the shift in the tan δ peak to represent each PSA's tack. These correlations were partially reflected in three commercial UV crosslinkable acrylic PSA products, although the effect of UV irradiation was less distinctive. This study also revealed the challenges in predicting tack and peel strength, which result from a complex interplay of bonding and debonding processes. Our findings reinforce the necessity for more sophisticated analysis techniques and models that can accurately predict the end-use performance of PSAs across different physical structures and chemical compositions. Further research is needed to develop these predictive models, which may reduce the need for labor-intensive testing under real-life conditions. [ABSTRACT FROM AUTHOR]

Downburst is a hazardous strong wind commonly encountered in thunderstorm weather. Influenced by ambient wind, the downdraft often accompanies horizontal movement while descending. Based on the impinging jet model, this study employs the large eddy simulation method to conduct computational fluid dynamics numerical simulations of stationary and moving downbursts. The evolution process, time-varying wind speed, and wind profile characteristics of the two types of wind fields are compared. This study also discusses the influence of η—which represents the ratio of the storm traveling speed (Vtr) to the jet velocity (Vjet)—on the wind field structure and verifies the applicability of the vector superposition principle in the simulation of the moving downburst. The results show the following: The wind speed and direction time histories obtained from the numerical simulation of moving downbursts have good consistency with the actual wind field records. The movement of the storm causes the near-surface wind field to lose its central symmetry, resulting in a bow-shaped distribution of extreme wind speeds at the storm's leading edge. As η increases, the non-central symmetry of the wind field becomes more pronounced, the maximum horizontal wind speed at the storm's leading edge gradually moves closer to the storm's center, peak wind speeds gradually increase, and the wind speed distribution at the storm's trailing edge shows the opposite trend. The vector superposition principle is not entirely applicable in the simplified analysis of moving downburst, causing significant errors when η is larger than 0.1. [ABSTRACT FROM AUTHOR]

Copyright of Atomic Energy Science & Technology is the property of Editorial Board of Atomic Energy Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The law of superposition underpins first-order linear pharmacokinetic relationships. Most drugs, therefore, after a single dose can be described by first-order or linear processes, which can be superposed to understand multiple-dose regimen behavior. However, there are a number of situations where drugs could display behaviors after multiple dosing that leads to capacity-limited or saturation non-linear kinetics and the law of superposition is overruled. This review presents a practical guide to understand the equations and calculations for single and multiple-dosing regimens after intravenous and oral administration. It also provides the pharmaceutical basis for saturation in ADME processes and the consequent changes in the area under the concentration–time curve, which represents drug exposure that can lead to the modulation of efficacy and/or toxic effects. The pharmacokineticist must implicitly understand the principles of superposition, which are a central tenet of drug behavior and disposition during drug development. [ABSTRACT FROM AUTHOR]

It was discussed that the research progress and technical achievements had been obtained in the field of residual stress measurement and control of high-grade and large-diameter welded pipe for oil and gas transportation in China. (1) The layout scheme of measuring points and the requirements of spaces between measuring points, hole depth, etc., for residual stress measurement of welded pipe using hole drilling strain-gage method were proposed. On which, the residual stress measurement technology for welded pipe was proposed. (2) The measurement results indicate that the characteristics and distribution of residual stress of SAWH pipes with different grades and sizes were quite different. In general, the residual stress of SAWH pipe was highest, followed by JCOE pipe and UOE pipe. After the ring splitting test, SAWH pipe section usually had relative displacement in circumferential, axial and radial directions, and the degree of deformation varies greatly; But SAWL pipe section usually only occurs circumferential opening, without axial and radial stagger, and the circumferential opening of JCOE pipe was usually larger than that of UOE pipe. (3) Based on the mechanical analysis of the complex deformation of SAWH pipe after the ring splitting test and the superposition principle of elastic mechanics, a prediction model of the residual stress of the high-grade and large-diameter welded pipe suitable for SAWH pipe was established, which overcame the deficiency of the existing prediction models of the residual stress of the welded pipe only considering the circumferential deformation. (4) The key forming parameters affecting the residual stress of SAWH pipe were analyzed and determined as the reduction and forming angle. Combined with the finite element simulation analysis, field adjustment and residual stress analysis, the forming technology and residual stress control technology of low residual stress SAWH pipe were developed. [ABSTRACT FROM AUTHOR]

Deep multilayered reservoirs are usually developed using multilayered fracturing techniques; however, the non-uniform placement of proppant causes uneven distribution of fracture conductivity. This study introduces a semi- analytical well test model for hydraulically fractured wells in multilayered reservoirs, accounting for varying fracture conductivity within the hydraulic fracture. The model is built upon the point source function, boundary element method, Duhamel theorem, and pressure superposition principle. Verification tests are conducted to ensure calculation accuracy. Sensitivity analysis is performed on key parameters, encompassing the transmissibility factor, storativity factor, fracture extension, and fracture conductivity. The findings indicate that 1) Increased heterogeneity among layers correlates with amore pronounced pressure drop; 2) Poorly- propped fracture conductivity influences the duration of bilinear flow, becoming negligible after linear flow; 3) The model's applicability extends to other multilayered reservoirs (e.g., carbonate reservoirs) with minor adjustments. Lastly, a case study from Xinjiang oilfield is presented to demonstrate that the proposed method can derive reservoir and fracture properties for each layer individually. This study contributes to a deeper understanding of the potential of pressure data in characterizing multilayered reservoirs. [ABSTRACT FROM AUTHOR]

A mathematical approach is proposed to apply strain-driven (εD) and stress-driven (σD) two-phase local/nonlocal integral models (TPNIMs) with discontinuity of variable fields. The equivalently differential form together with constitutive boundary conditions and constitutive continuity conditions is derived explicitly. Compare to constitutive boundary conditions, constitutive continuity conditions have one more integral item, and the discontinuity plays no role on differential constitutive relation and constitutive boundary conditions. εD- and σD-TPNIMs are applied to formulate the Mode I and II fracture problem of double cantilever Euler-Bernoulli microbeams subjected symmetric and anti-symmetrical end moment and force loads. It is found that constitutive continuity conditions play no role on Mode I fracture problem since that the flexible deformation disappears for intact microbeam under symmetry loads. The bending deflections under different loads are solved analytically, and the energy release rate (ERR) and stress intensity factor (SIF) are derived explicitly. On the basis of the superposition principle, SIF for edge-cracked Euler-Bernoulli microbeams subjected generally end moment and force can be calculated. The influence of nonlocal parameters and the intact microbeam length on the size-dependent fracture behavior is investigated numerically. The obtained results can explain the superior fracture performance of nanomaterials. [ABSTRACT FROM AUTHOR]

• A semi-analytical method is adopted for arbitrary fluid-conveying spatial pipeline. • The actual flexible-bracket clamp stiffness is considered. • Virtual springs are used for the straight-curved connection. In-depth research is imperative for complex spatial pipelines with fluid-structure interaction. A comprehensive and universal three-dimensional semi-analytical modeling method is first established for complex fluid-conveying spatial pipelines under the base excitation with arbitrary connections and configurations under different boundary conditions. The virtual spring technology is used to connect the straight and curved pipeline segments with spatial angles and simulate boundary conditions. For a thorough analysis, the actual stiffness of the bracket-clamp system is experimentally measured for the first time. The multi-level coupling dynamic model of part, component, and system levels under actual boundary conditions is established. An efficient method for solving the fluid-structure coupling pipeline system dynamics considering the base excitation is proposed based on energy method. The mid-plane displacement function of the Fourier series is introduced and solved using the principle of modal superposition. Hammer impact modal experiments, ANSYS software and vibration response experiments are performed on spatial pipelines supported by flexible bracket-clamps; the numerical and experimental results support the semi-analytical results. The degenerate model is verified with the simple plane pipelines in other references, and the errors are less than 5 %. The proposed method exhibits broad applicability and generalizability, making it suitable for various configurations and boundary conditions. [ABSTRACT FROM AUTHOR]

• This manuscript firstly establishes a half vehicle-pavement-continuous beam bridge (VPCB) coupled system analytical model. • It is innovatively that the bridge and vehicle initial conditions are considered into analytical model. • The pavement road surface local deterioration is simulated by increasing the local roughness level of the road surface. At present, the highway bridge field is in a period of vigorous development, and the application of continuous beam bridges is becoming more extensive, so the related safety research is particularly important. However, there are few studies on the vehicle-bridge coupled interaction of continuous beam bridges, and the influence of pavement is not considered. In order to ensure that the theoretical research can better serve the engineering practice, it is urgent to establish a more refined and more complex vehicle-bridge coupled model. In this paper, a vehicle-pavement-continuous beam bridge (VPCB) coupled system model is established. A half-vehicle model is adopted, the pavement is simulated by a continuous and uniform spring damper, and the bridge is a three-span continuous beam bridge. The motion equation of VPCB system is established and deduced using D 'Alembert principle and modal superposition method. The dynamic responses of VPCB system are calculated by Newmark- β method. Here, the continuous beam bridge mode functions are fitted based on the modal vector of the continuous beam calculated by the finite element model. The correctness of the method is verified by existing literatures. The effects of bridge pavement, vehicle speed, bridge second span length, the pavement equivalent spring stiffness coefficient k p and damping coefficient c p , road roughness on VPCB system are studied. The results show that the pavement can reduce the bridge dynamic amplification factor (DAF) and the vehicle acceleration to improve the ride comfort. The dynamic responses of the vehicle and the bridge contain each other's natural frequencies. The responses of VPCB system increase with the vehicle velocity, the vehicle responses are more affected than the bridge responses. The pavement equivalent stiffness and damping coefficient has little effect on the system. The responses of vehicle and bridge increase with the increase of the bridge second span length. When the vehicle travels each span of the three-span continuous beam bridge, the time history curve of the pavement deformation under the tire resembles a sine wave. When the local roughness level of the road surface increases, the system responses at the deteriorated position suddenly increases, and the responses of the subsequent position will also be affected. The larger the roughness grade, the more obvious the responses increase. The effect on the system responses of the whole pavement damage is more significant than the local pavement damage. [ABSTRACT FROM AUTHOR]

In this paper, an optically reconfigurable coded metasurface based on photosensitive silicon material for generating multi-channel, multi-mode vortex beams in the terahertz band is proposed. The top layer of the proposed metasurface is a skeletonized metal ring with eight photosensitive silicon patches equidistantly filled in the middle; the bottom structure is a metal plate for reflecting electromagnetic waves. The coding process of the eight photosensitive silicon patches and the use of a spatially structured light source for aligned irradiation can realize the reflection phase reconstruction and form a 3-bit reconfigurable metasurface. Based on the principle of coded metasurface convolution and the principle of superposition, the phase distributions of 3-bit metasurface arrays for single-channel and multi-channel vortex beams are calculated. Under the excitation of a right circularly polarized plane wave, a vertically reflected +1 order vortex wave, a +2 order vortex wave reflected in the tilted direction, +2 and +3 order vortex waves in two directions, and vortex beams carrying orbital angular momentum of orders −2, +1, +2, and +3 in four different directions, respectively, are generated. Our work provides a new way to design a programmable and reconfigurable metasurface, and the designed novel optically controlled reconfigurable metasurface is potentially valuable in the fields of dynamic imaging, terahertz communication, and so on. [ABSTRACT FROM AUTHOR]

In recent years, there has been an increased interest in understanding and predicting the weather using weather station data with Spatial-Temporal Graph Neural Networks (STGNN). However, it has large prediction errors as a result of the inherent non-linearities and the influence of dynamic spatio-temporal auto-correlation. Using a continuously-varying graph topology chronologically, while embedding domain knowledge to enforce validity, can effectively resolve the issue, but the implementation of such concept constitutes an interdisciplinary challenge for researchers. A Dynamic Graph Former (DGFormer) model is proposed to address this challenge. It combines a topology learner through a deep generative layer with domain knowledge enhancement inserted into the STGNN structure, where the derived physics-guided method allows for an efficient integration with the earth system. For capture of the optimal topology, we merge a node-embedding-based similarity metric learning and the superposition principle as physical assistants into the dynamic graph module. We evaluate our model with a real-world weather dataset on short-term (12 hours) and medium-range (360 hours) prediction tasks. DGFormer achieves outstanding performance with obvious improvements by up to 34.84% at short-term prediction and by up to 23.25% at medium-range prediction compared with the state-of-the-art methods. We also conducted detailed analyses for cities in three regions and visualized the dynamic graph, revealing the characteristics, advantages, and graph visualization of our model. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Drainage & Irrigation Machinery Engineering / Paiguan Jixie Gongcheng Xuebao is the property of Editorial Department of Drainage & Irrigation Machinery Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The purpose of this paper is to test the performance of the recently proposed weighted superposition attraction-repulsion algorithms (WSA and WSAR) on unconstrained continuous optimization test problems and constrained optimization problems. WSAR is a successor of weighted superposition attraction algorithm (WSA). WSAR is established upon the superposition principle from physics and mimics attractive and repulsive movements of solution agents (vectors). Differently from the WSA, WSAR also considers repulsive movements with updated solution move equations. WSAR requires very few algorithm-specific parameters to be set and has good convergence and searching capability. Through extensive computational tests on many benchmark problems including CEC’2015 and CEC’2020 performance of the WSAR is compared against WSA and other metaheuristic algorithms. It is statistically shown that the WSAR algorithm is able to produce good and competitive results in comparison to its predecessor WSA and other metaheuristic algorithms. [ABSTRACT FROM AUTHOR]