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Within electrical distribution networks, substation constraints management requires that aggregated power demand from residential users is kept within suitable bounds. Efficiency of substation constraints management can be measured as the reduction of constraints violations w.r.t. unmanaged demand. Home batteries hold the promise of enabling efficient and user-oblivious substation constraints management. Centralized control of home batteries would achieve optimal efficiency. However, it is hardly acceptable by users, since service providers (e.g., utilities or aggregators) would directly control batteries at user premises. Unfortunately, devising efficient hierarchical control strategies, thus overcoming the above problem, is far from easy. We present a novel two-layer control strategy for home batteries that avoids direct control of home devices by the service provider and at the same time yields near-optimal substation constraints management efficiency. Our simulation results on field data from 62 households in Denmark show that the substation constraints management efficiency achieved with our approach is at least 82% of the one obtained with a theoretical optimal centralized strategy.

Three-dimensional Integrated Circuits (3D-ICs) is a cutting-edge design methodology of placing the circuitry vertically aiming for a high-speed and energy-efficient system with the smallest design area. In this paper, a novel 3D neuromorphic system is proposed and analyzed, which utilizes the fabricated two-layer memristor as the electronic synapses in a spiking neural network (SNN). The two-layer structure of the memristors leads to a significant improvement in the design area (2×), power consumption (1.48 ×), and latency (2.58×), compared to the traditional one-layer configuration. Meanwhile, the heat dissipation layers are added to our memristors reducing 30% cycle-to-cycle switching variation. Our memristive synapses are utilized for storing the exported weights of the SNNs that have threshold function as the activation function. The proposed neuromorphic system is evaluated using a hardware-software co-design approach importing the weights of SNNs into NeuroSIM. The simulation results demonstrate the significant improvement of memristive synapses on design area, power consumption, and latency, compared with the SRAM (Static Random-access Memory) and other state-of-the-art memristive synapses (10% to 66%).

A crucial problem of neural networks is to select an architecture that strikes appropriate tradeoffs between underfitting and overfitting. This work shows that L1 regularizations for two-layer neural networks can control the generalization error and sparsify the input dimension. In particular, with an appropriate L1 regularization on the output layer, the network can produce a tight statistical risk. Moreover, an appropriate L1 regularization on the input layer leads to a risk bound that does not involve the input data dimension. The results also indicate that training a wide neural network with a suitable regularization provides an alternative bias-variance tradeoff to selecting from a candidate set of neural networks. Our analysis is based on a new integration of dimension-based and norm-based complexity analysis to bound the generalization error.

To better understand the self-regulated learning process in online learning environments, this research applied a data mining method, the two-layer hidden Markov model (TL-HMM), to explore the patt...

Safety-critical situations in road traffic often result from incorrect estimation of the future behavior of other road users. Therefore, many Advanced Driver Assistance Systems (ADAS) need prediction models to ensure safety. Physical prediction models offer the advantage of general use and work quite well for short prediction horizons, while for longer periods of time, maneuver-based models offer better performance which, however, strongly depends on the data used to train them. An additional challenge for prediction is the fact that the surrounding traffic can change its path, i.e. for safety not only one maneuver should be considered but regular updates are required. Against this background, we propose a method that uses three physics-based predictions – corresponding to different prediction assumptions and models – combined with possible maneuver-based trajectories derived from environmental knowledge. Continuous monitoring is used to select the most likely of the three physics-based models. This choice then influences the environment-based prediction and the output of both models is fused afterwards. The output of the resulting Multiple Model Trajectory Prediction (MMTP) has been validated with measured data from two different scenarios – a city junction and a highway – with a good prediction performance and without the need for special measurements as commonly required for maneuver-based prediction.

In this paper, forming limit diagram (FLD) of aluminum/brass two-layer sheets through an incremental forming process (ISF) was studied numerically and experimentally. At first, the two-layer aluminum 1050/brass (65% copper) sheets were fabricated using the roll bonding process. Also, the finite element simulations of the incremental forming process with ABAQUS software were utilized to predict the FLD. For this purpose, the criterion of the second derivative of the equivalent plastic strain was used to predict fracture. Finally, the numerical simulation results were compared with the experimental results. For instance, comparing experimental and numerical FLD0 values for the formed samples with forming angle 62.5-degree showed a 7% difference. However, the difference was negligible, and numerical simulation results could be used with an appropriate reliability coefficient. The effect of sheet arrangement towards tools was then investigated. It finds out from the experimental results that the formability of the Brass/Al (brass was up layer and aluminum was bottom layer) was more than the Al/Brass (aluminum is up layer and brass is bottom layer). In the following, the ISF parameters such as forming limit angle, step-down, and thickness distribution were investigated.

The objective is to know the stress distributions in the arterial walls under residual stresses based on two-layer model. Human common carotid arteries were analysed to show stress distributions at physiological and supraphysiological intraluminal pressures. The analyses for the loaded states were performed with stretch ratios with reference to a Riemannian stress-free configuration which is a 3D non-Euclidean manifold due to the nonzero Riemann curvature tensor. The experimental data obtained by other literature were used for the common carotid arteries to analyse the stretch and stress distributions in the arterial wall although kinematics is different from the literature. The stretches and stresses were calculated for the unloaded state, i.e. the residual stretches and stresses. And those at the axial stretch ratio 1.1 with reference to the unloaded state were calculated at the intraluminal pressures 16, 50, and 100 kPa. The stresses increased from the inner surface to the outer surface at all pressures analysed. These results suggest that in the human arteries the mechanical loads are mainly supported with the adventitia even though the media and intima play an important role to control of physiological functions.

It is known that, when dealing with 50–60 Hz electromagnetic interference problems between power/railway lines and metallic pipelines/telecommunication cables, an important role is played by the soil modeling. To this aim, this paper presents a novel algorithm devoted to the construction of an equivalent two-layer soil model starting from the combined use of data available from different kinds of earth conductivity maps: on one side, the ones related to the geological characteristics relevant to the area of interest and, on the other side, the ones based on radio electric propagation measurements. From these data and by means of a suitable algorithm, the parameters characterizing the equivalent two-layer soil model are obtained.

Purpose To reduce the heat load of a gas turbine blade, its surface is covered with an outer layer of ceramics with high thermal resistance. The purpose of this paper is the selection of ceramics with such a low heat conduction coefficient and thickness, so that the permissible metal temperature is not exceeded on the metal-ceramics interface due to the loss ofmechanical properties. Design/methodology/approach Therefore, for given temperature changes over time on the metal-ceramics interface, temperature changes over time on the inner side of the blade and the assumed initial temperature, the temperature change over time on the outer surface of the ceramics should be determined. The problem presented in this way is a Cauchy type problem. When analyzing the problem, it is taken into account that thermophysical properties of metal and ceramics may depend on temperature. Due to the thin layer of ceramics in relation to the wall thickness, the problem is considered in the area in the flat layer. Thus, a one-dimensional non-stationary heat flow is considered. Findings The range of stability of the Cauchy problem as a function of time step, thickness of ceramics and thermophysical properties of metal and ceramics are examined. The numerical computations also involved the influence of disturbances in the temperature on metal-ceramics interface on the solution to the inverse problem. Practical implications The computational model can be used to analyze the heat flow in gas turbine blades with thermal barrier. Originality/value A number of inverse problems of the type considered in the paper are presented in the literature. Inverse problems, especially those Cauchy-type, are ill-conditioned numerically, which means that a small change in the inputs may result in significant errors of the solution. In such a case, regularization of the inverse problem is needed. However, the Cauchy problem presented in the paper does not require regularization.

A mathematical model for determining the temperature in a two - layer shell under convective heating and heat sources is constructed. The temperature field for a two-layer shell thermally insulated on the inner surface, which is heated by temperature from the outer surface, is considered.

AIM To study the influence of the technique of posterior reconstruction of the vesicourethral anastomosis (VUA) on the prevention of urinary incontinence after robotic-assisted radical prostatectomy (RARP). MATERIAL AND METHODS A total of 67 patients (mean age 63 years) with localized prostate cancer were included in the study. All patients were divided into two groups. In the group 1 (n=32) the standard technique of the VUA was used, while in the group 2 (n=35) the two-layer posterior reconstruction was done. The impact of urinary incontinence on the quality of life was analyzed using the ICIQ-SF questionnaire 1, 3 and 6 months after operation. On postoperative days 5-7, all patients underwent cystography to assess the tightness of the VUA. RESULTS One month after RARP in the group 1 the mean score of ICIQ-SF questionnaire was 6.72, compared to 4.57 in group 2 (p=0.04). After 3 and 6 months the respective values were 3.8 vs. 2.3 (p=0.09) and 1.94 vs. 1.2 (p=0.23), respectively. Cystography revealed no extravasation of the contrast. CONCLUSION The results of a retrospective comparative study suggest that a two-layer posterior reconstruction of the VUA during RARP, being a simple method, provides better continence rate one month postoperatively compared to standard technique, although larger randomized clinical trials are needed.

This study evaluated Life-Cycle Assessment (LCA) of two different designs of high-performance concrete beam: (1) a single-layer beam (SLB) that consisted of steel fibered high-strength concrete in both the compression and tensile zones and (2) a two-layer beam (TLB) that consisted of steel fibered high-strength concrete and normal-strength concrete in the compression and tensile zones, respectively. The SLB and steel fibered high-strength concrete layer of the TLB were of the same concrete class C70/85. LCAs of the SLB and TLB were conducted using the ReCiPe2016 midpoint and endpoint-single-score methods. The difference between the two endpoint-single-score results was evaluated using a two-stage nested analysis of variance. The ReCiPe2016 midpoint results showed that replacing the SLB with the TLB reduces the environmental impact of global warming potential, terrestrial ecotoxicity, water consumption, and scarcity of fossil resources by 15%, 17%, 11%, and 17%, respectively. The ReCiPe2016 endpoint-single-score results showed that the environmental damage from the TLB compared to the SLB was statistically reduced (p = 0.0256). Therefore, considering two different designs of steel fibered high-strength concrete beams, the TLB design was found environmentally preferable to SLB design on both, midpoint and endpoint-single-score evaluations.

This paper presents the results of direct laser recording on a two-layer amorphous silicon / silver structure deposited on a glass substrate by magnetron sputtering. The absorption spectra of a-Si films of various thicknesses and a glass substrate are investigated. A method is proposed for direct laser recording of microstructures by focused radiation of a single-mode semiconductor laser with a wavelength of λ = 405 nm on a two-layer a-Si / Ag medium from the side of a glass substrate. The formation of the micro relief is studied during direct recording by semiconductor laser pulses with λ = 405 nm on the a-Si layer. Parameters of two-layer structure a-Si / Ag for direct laser recording are optimized.

We report the study of sudden transitions or tipping in a collection of systems induced due to multiplexing with another network of systems. The emergent dynamics of oscillators on one layer can undergo a sudden transition to steady state due to indirect coupling with a shared environment, mean field couplings and conjugate couplings among them. In all these cases, when multiplexed with another set of similar systems, the tipping phenomena are induced on the second layer also with a similar pattern of behaviour. We consider van der Pol oscillator as nodal dynamics with various network topologies like scale free and regular networks with local and nonlocal couplings. We also report how the coupling topology influences the nature of transitions on both layers, under multiplexing., Comment: 16 pages, 11 figures

As is well known, complex networks in reality are usually interconnected. To describe the interconnected networks, multiplex networks were presented recently. In this brief, an aperiodically intermittent pinning control scheme is put forward to realize cluster exponential synchronization in a two-layer (leader-follower) network with multi-links and time-varying delays. Based on the principle of intermittent control and Lasalle invariant principle, some criteria for cluster synchronization are deduced by theoretical analysis. Numerical simulations are provided to verify the effectiveness of the proposed scheme. In comparison with the previous methods, our model better describes the real-world networks and our control effectively reduces the control cost.

A numerical study of the magnetization reversal of a two-layer exchange-coupled ferromagnetic plate of finite dimensions, which has a combined uniaxial anisotropy (of the "easy axis" type for the upper layer and «easy plane» for the lower one) and cubic anisotropy with orientation [111]. It is shown that, in the presence of cubic anisotropy, the ground state of magnetization turns out to be uniform in the plane of the film. However, there is discontinuity at the interface between the film layers. This inhomogeneity can lead to the appearance of electric polarization due to the magnetoelectric effect. The electric polarization vector in this case lies in the plane of the film. Its modulus increases with increasing cubic anisotropy. In addition, with an increase in cubic anisotropy, a hysteresis of electrical polarization is observed.

A series of lock-release experiments are carried out to investigate the hydrodynamics of weakly and strongly stratified two-layer gravity currents (GC) on a flat bottom. A particle image velocimetr...

In this work, based on the results of dynamic mechanical studies, the damping efficiency of two-layer polyurethane (PU) composites designed by gluing two films of synthesized PU with different glass transition temperatures (Tg) was estimated. The damping efficiency was estimated by the parameters of the mechanical losses (tanδ) peak. To vary Tg, three types of PU with different chemical nature and structure were synthesized. The effect of an increase in the difference between the Tg of the initial PU (ΔTg) on the damping efficiency of the two-layer PU composites formed from them is analyzed. The effective damping temperature range (ΔT) was estimated as the temperature range under conditions tanδ ≥ 0,3 and tanδ ≥ 0,6. It was shown that at ΔТg = 7 °С a two-layer PU composite has one relaxation maximum, and its temperature range of damping efficiency expands in comparison with ΔТ for individual PU. Under the conditions ΔТg = 23 °С and ΔТg = 30 °С, two-layer PU composites exhibit damping efficiency in two temperature regions at tanδ ≥ 0,3, which provides an additional temperature range of effective damping. The essential role of the PU structure of each of the layers in the formation of a two-layer composite by gluing has been determined. Easier penetration of residues of the adhesive organic solvent into the surface of the PU film with a linear structure leads to plasticization of the corresponding layer in the composite and reduces Tg. It is shown that a two-layer structure can be used to solve specific problems related to the adjustment or broadening the effective damping temperature range.

In this article, we present two efficient closed-form models to examine thoroughly the dependence of resonant frequency, quality factor, probe reactance, input impedance, bandwidth, and gain on parameters such as patch radius, probe location, substrate electrical parameters, and air gap of a coax probe-fed circular patch antenna. The implementation of these models is very easy and the computation cost is very low. The proposed models show excellent agreements with experimental and simulation results. We have also investigated experimentally the gain patterns of a suspended substrate circular patch antenna.

Effective grounding is the most important aspect in every electrical installation because it can ensure efficient equipment operation in the event of electrical faults. Measurement data of soil resistivity is used to assess the suitability of the soil for grounding purpose and also to evaluate the structures of the soil. However, the limitation of soil resistivity measurement is various investigations on two‐layer soil structures cannot be performed due to the variation of natural soil structures is limited. Therefore, in this work, modelling of soil resistivity of two‐layer soil structures was proposed using finite element analysis method to estimate the depth of upper layer of non‐homogeneous soil based on the measurement results from Wenner and Schlumberger methods. Also, using the proposed method, the effect of soil resistivity of each layer on the overall two‐layer soil resistivity was investigated. To validate the results obtained from the proposed method, comparison between the FEA results and measured field data was made. It was found that the average error between both results is

Micromixers are key components of microfluidic systems for sample analysis, bioreactors, drug delivery, and many other applications. To date, numerous passive micromixer designs have been proposed. Among those, several designs with complex design structures have been demonstrated to be efficient. In the present work, the authors try to propose a new efficient design with low complexity in terms of fabrication. The new design is two-layer and is based on the split and recombination (SAR) and vortex mixing principles. It is suggested to fabricate the new design in polydimethylsiloxane (PDMS) using the soft lithography technique. This new design is chosen among three new designs simulated using the computational fluid dynamics (CFD) software ANSYS Fluent 17.0. The three new designs are named ND1, ND2, and ND3 and their mixing performances are evaluated numerically using mixing index (MI) and mixer effectiveness (ME) quantities at four different Reynolds (Re) numbers in the range of 0.1–100. Calculated values are compared with those obtained for the classical Y-shaped (CY) micromixer. Flow and mixing patterns are computed by solving the continuity, Navier–Stokes, and the convection–diffusion equations. CFD results for the CY micromixer are compared with available experimental and numerical data and reasonable agreement is observed. According to the results, ND3 has the highest performance (ME up to 36.86 percent/mm) among the investigated micromixer designs in the entire range of Re numbers. The maximum pressure drop (35099.9 Pa at Re = 100 for ND3) is still in the range of acceptable pressure drops reported in the literature. ND3 can be used as an efficient substitute for CY. Although ND3 is highly efficient (MI up to 99.52%) at Re numbers lower than 0.3 or higher than 50, its performance at the intermediate Re numbers (0.3

The two-layer pile-rock porous breakwater consisting of the upper porous layer, middle porous layer placed over the bottom rigid layer (elevated bottom) is proposed as an active wave absorber for s...

In this study, two vortex rings composed of upper fluid were continuously ejected vertically downward toward the interface of the two-layer density-stratified fluid. The motion of the vortex rings and behavior of the lower layer fluid were investigated via visualization experiment, and the effect of time interval between the injections of the two vortex rings on the mixing of the density-stratified fluid was investigated. The first emitted vortex ring (VRA) advected vertically downward in the upper layer, passed through the density interface, and then advected in the lower layer. After VRA reached the maximum depth in the lower layer, the upper part of the fluid mass ejected into the upper layer due to buoyancy. The lower fluid was entrained in the upper layer. Subsequently, a new vortex ring (VRC) was generated by the fluid mass ejected in the upper layer and advected vertically upward in the upper layer. The second vortex ring emitted (VRB) collided with the tip of the fluid mass of the VRA ejected from the lower layer. Subsequently, it slightly penetrated the lower layer, rolled up the lower layer fluid into the upper layer, and coalesced with VRC to collapse. In the process of vortex merging, the mixing of the upper and lower layers reached a maximum when the VRA reached the maximum depth. Furthermore, it was clarified that the mixing ability of the upper and lower layers depends on the ejection time interval of the two vortex rings.

Sawtooth two-layer microstructures with internal and external, as well as with two internal reliefs, composed of technological and commercially available optical plastics or an optical plastic and nanocomposite material are investigated. By using the corresponding model microstructures in the frameworks of the rigorous diffraction theory, the limiting spectral and angular characteristics are estimated for sawtooth two-layer dual-relief diffraction microstructures of both types.

In the present study, we investigate a universality of neural networks, which concerns a density of the set of two-layer neural networks in function spaces. There are many works that handle the convergence over compact sets. In the present paper, we consider a global convergence by introducing a norm suitably, so that our results will be uniform over any compact set.

Wrinkling, which is primarily caused by insufficient blank holder force, is a significant issue that induces inconsistencies in forming parts, particularly in the deep drawing process. In this article, an investigation of the wrinkling in the deep drawing process of two-layer sheets is performed through an analytical approach, numerical method, and experimental tests. Increasing in the blank holder force, the process is under control by the proposed algorithm. Consequently, it aims to find the minimum required blank holder force to avoid wrinkling. The energy technique is utilized to predict the wrinkling in the analytical approach. Similarly, finite element simulations are implemented to investigate the effect of forming parameters on wrinkling. The experimental tests are performed to verify the analytical and numerical results. The impact of the material properties and stacking sequences (lay-up) on blank holder force and forming force are studied. Results show that the optimum blank holder force is dependent on the material properties, blank geometry, and layer stacking sequences. Also, a good agreement between analytical, numerical, and experimental results is achieved.

A 3-D reconstruction method and multicamera calibration using multiple artificial reference markers have been used for precise volumetric surveillance of fast-flying objects. The method uses a two-layer 3-D reconstruction that integrates two multicamera stereo nodes. The fields of view of stereo nodes are directed at an acute angle to each other to provide greater coverage with the given constraints and to determine the flight characteristics of objects in 3-D. The object’s flight reconstruction includes a “rough” estimation of its positions relative to selected artificial reference points in both stereo nodes separately and subsequent “refinement” of calculated positions. In this article, we describe the proposed method and calibration technique using a multicamera system to measure the object characteristics in 3-D. The proposed method applies to volumetric surveillance in situations where it is necessary to count, track, and analyze the activities of flying objects, especially birds, using high spatial resolution.

On the basis of proposed new filtration model the peculiarities of concentration distribution of component carried by two-component biological liquid and fluid velocity in capillary with two-layer porous walls in steady-state mode are studied. Mathematical model takes into account such important phenomena as concentration expansion and viscosity dependence on concentration. The fluid flow corresponds to the Brinkman model. Dimensionless complexes linking characteristic physical scales of different phenomena are highlighted. Influence of model parameters on biological liquid filtration process for capillary wall layers with different porosity is analyzed. The peculiarities of flow regime and distribution of component concentration for different characteristics of internal porous layer (porosity, phase mobility, size) are revealed.

The phenomenon of chimera state cloning in a two-layer network of bistable time-delayed feedback oscillators has been experimentally studied for the first time in cases of unidirectional and mutual coupling between the network layers. It is established that the cloning of chimera states in the case of mutual coupling is only possible provided a proper choice of the initial conditions for oscillators.

The nonstationary problem of thermal conductivity in a two-layer thermal protection coating is under consideration. The solution is given for a metal hemispherical shell with axisymmetrical distribution of the heat flux density over the outer surface of the coating.

A family of weighted two-layer finite-difference schemes is presented. Using the example of the numerical solution of model problems on the propagation of a single soliton and the interaction of two solitons, the high quality of explicit-implicit schemes of the Crank-Nichols type with a weight parameter of 0.5 and a second order of approximation in the time and space variables is shown. Absolute stability with a low accuracy of the solution due to a large approximation error is characteristic of completely implicit two-layer difference schemes with a weight parameter of 1, first order in time and second in space. A family of explicitly implicit difference schemes is absolutely unstable if the explicitness parameter less than 0.5 prevails. Analysis of the structure of the approximation error, performed using the modified equation method, confirmed the results of numerical simulation.

This paper considers the effects of forced and mutual synchronization of complex spatio-temporal structures in a two-layer network of nonlocally coupled logistic maps in the presence of inhomogeneous interlayer coupling. Two different types of coupling topology are considered: the first one is the sparse interlayer coupling with randomly distributed coupling defects, and the second type is the cluster interlayer coupling, providing the coupling via designated finite groups of elements. The latter type of coupling topology is considered for the first time. As a quantitative measure of the synchronization effect on the network, variance averaged over time and variance averaged both over time and network elements are used. We analyze how the synchronization measure changes depending on a degree of the interlayer coupling sparseness. We also identify a cluster of network elements which can provide almost complete synchronization in the network under study when the interlayer coupling is introduced along them.