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In this paper, we propose a cellular automaton model to investigate the traffic flow characteristics in the traffic circle system with adaptive traffic lights control. The traffic flow in the circulating lane was evaluated and depending on it the traffic lights lit red in the entry lanes to reduce the coming traffic. The density and the satisfaction rate were used as feedback to control the traffic flow in the circulating lane. It is found that both parameters (i.e. the density and the satisfaction rate in the circulating lane), if they are used as a criterion to control the coming traffic from entry lanes, promote the throughput in the traffic circle system. Traffic flow for the traffic circle system without using the traffic lights was investigated. In this case, we find that the traffic flow in the system is characterized by three phases, namely, gridlock, congestion, and free flow. The gridlock phase is predominant over the other phases. Furthermore, with the use of the adaptive traffic lights, the gridlock phase has vanished and the maximum current, jammed, and congestion phases take place. The density criterion shows good performance as compared with the satisfaction rate criterion in terms of the lengths of the red cycle. The capacity is also investigated. The space-time configurations were given to understand the microscopic interaction between vehicles. [ABSTRACT FROM AUTHOR]

In this paper, we propose a cellular automaton model to simulate traffic flow controlled by a series of traffic lights. The synchronized traffic light and the green wave light strategies were investigated. The spatiotemporal diagrams, energy dissipation, and CO2 emission of the system were presented. Our simulations are conducted to clarify the difference between both strategies and their effects on the traffic flow and the CO2 emission. We found that the traffic flow depends mainly on the strategy used for managing the traffic lights as well as on the parameters of the traffic lights, namely the cycle length, the number of traffic lights and the length of the system. The fundamental diagram has barely the same characteristics for both methods and it depends on the combination of the parameters of the system. We find that the green wave is more convenient for the management of a series of traffic lights than the synchronized control strategy in terms of throughput, especially for large-sized systems. Unlike in terms of CO2 emission and energy dissipation, both control strategies outperform each other depending on the density regions and the parameters of the system. Finally, we investigate the effect of both cycles (i.e. red and green) for the synchronized control method on the CO2 emission. It is found that the green cycle generates often a series of acceleration events that increase CO2 emission. [ABSTRACT FROM AUTHOR]

In traffic networks, it is quite important to assign proper packet delivering capacities to the routers with minimum cost. In this respect, many allocation models based on static and dynamic properties have been proposed. In this paper, we are interested in the impact of limiting the packet delivering capacities already allocated to the routers; each node is assigned a packet delivering capacity limited by the maximal capacity of the routers. To study the limitation effect, we use two basic delivering capacity allocation models; static delivering capacity allocation (SDCA) and dynamic delivering capacity allocation (DDCA). In the SDCA, the capacity allocated is proportional to the node degree, and for DDCA, it is proportional to its queue length. We have studied and compared the limitation of both allocation models under the shortest path (SP) routing strategy as well as the efficient path (EP) routing protocol. In the SP case, we noted a similarity in the results; the network capacity increases with increasing . For the EP scheme, the network capacity stops increasing for relatively small packet delivering capability limit for both allocation strategies. However, it reaches high values under the limited DDCA before the saturation. We also find that in the DDCA case, the network capacity remains constant when the traffic information available to each router was updated after long period times . [ABSTRACT FROM AUTHOR]

In this paper, we present a cellular automata model to depict the traffic characteristics at such a nonsignalized -shaped intersection in the presence of pedestrian crossings. The vehicular traffic flow characteristics with different parameters are studied. Throughput, phase diagrams, space-time and density profiles are built to point various traffic states and the phase transition features. The principal finding of the simulation are as follows: (1) The presence of crossing pedestrians has a significant influence on the vehicular traffic and the system performance, (2) The intersection capacity has a close relevance with the state of the weaving section. The smaller the interactions are at the weaving section, the higher the capacity and (3) In order to have a higher system ability, the crosswalk location should not be far from the yield line of the weaving section. [ABSTRACT FROM AUTHOR]

In this paper, a new model of the interdependent complex network is proposed, based on two assumptions that (i) the capacity of a node depends on its degree, and (ii) the traffic load depends on the distribution of the links in the network. Based on these assumptions, the presented model proposes a method of connection not based on the node having a higher degree but on the region containing hubs. It is found that the final network exhibits two kinds of degree distribution behavior, depending on the kind and the way of the connection. This study reveals a direct relation between network structure and traffic flow. It is found that the point of transition between the free flow and the congested phase depends on the network structure and the degree distribution. Moreover, this new model provides an improvement in the traffic compared to the results found in a single network. The same behavior of degree distribution found in a BA network and observed in the real world is obtained; except for this model, the transition point between the free phase and congested phase is much higher than the one observed in a network of BA, for both static and dynamic protocols. [ABSTRACT FROM AUTHOR]

This paper proposes a vehicle–pedestrian cellular automata model to investigate the characteristics of the mixed traffic at a single lane roundabout. The roundabout boundary is controlled by the injecting rates α 1 , α 2 and the extracting rate β whereas pedestrians are generated with arrival probability P cr . The pedestrian and vehicle flux are calculated in terms of rates. Also, the phase diagrams of the system in the ( α 1 , P cr ) and ( α 1 , β ) spaces are constructed. The results show that, the gridlock state is reached only when the pedestrians have the right of way over vehicles, while the maximum current state is reached when including a pedestrians’ crossing decision rule. Likewise, we have found that the crosswalk location play a chief role in improving the dynamic characteristics of pedestrian and vehicle flux. Furthermore, it has turned out that the traffic is sensitive to the driver behavior. [ABSTRACT FROM AUTHOR]

The shortest path is a basic routing model which is still used in many systems. However, due to the low exploitation of the delivery capacity of peripheral nodes, the performance achieved by this policy is very limited. Starting from the fact that changing all network routers by others more robust is not practical, we propose the improvement of the capacity of a scale-free network under the shortest path strategy by the implantation of global dynamic routers. We have studied two targeting approaches to designate specific nodes to route the packets following the global dynamic protocol; one is based on node degree and the other on its betweenness. We show that we already exceed twice the capacity under the shortest path protocol with only 4 % of global dynamic routers when we target nodes with high betweenness and 10 % when we target nodes with high degrees. Moreover, the average travelling time remains low while the network capacity increases. [ABSTRACT FROM AUTHOR]

Optical properties of ZnO doped with Silicon and Aluminum were studied by first principle calculations using the density functional theory. The optical absorption, transmittance and optical constants are investigated using the full potential-linearized augmented plane wave method with the generalized gradient approximation and mBJ approximation, implemented in Wien2k package. With the mBJ approximation the direct optical gap of a pure ZnO is about 3.34 eV, which is in good agreement with experimental results. The behavior of the transmittance and the absorption of the Al-doped ZnO are higher and better than those of the Si-doped ZnO. The transmittance of Al-doped ZnO is stable and high in the visible light range and can reach 96 % at 400 nm. This confirms the physical characteristics that can present Al to be used as suitable transparent material electrodes in solar cells. [ABSTRACT FROM AUTHOR]

Using cellular automata (CA) Nagel–Schreckenberg (NaSch) model, we numerically study the probability Pac of the occurrence of car accidents at nonsignalized intersection when drivers do not respect the priority rules. We also investigated the impact of mixture lengths and velocities of vehicles on this probability. It is found that in the first case, where vehicles distinguished only by their lengths, the car accidents start to occur above a critical density ρc. Furthermore, the increase of the fraction of long vehicles (FL) delays the occurrence of car accidents (increasing ρc) and increases the risk of collisions when ρ > ρc. In other side, the mixture of maximum velocities (with same length for all vehicles) leads to the appearance of accidents at the intersection even in the free flow regime. Moreover, the increase of the fraction of fast vehicles (Ff) reduces the accident probability (Pac). The influence of roads length is also studied. We found that the decrease of the roads length enhance the risk of collision. [ABSTRACT FROM AUTHOR]

In this paper, we propose a stochastic Cellular Automata (CA) model to study traffic flow at a single-lane urban roundabout (resp. traffic circle) of N entry points (resp. exit points), the entry points are controlled by rates α 1 and α 2 while the removal rates from the exit points are denoted by β . The traffic is controlled by a self-organized scheme. Based on computer simulation, density profiles, global density and current are calculated in terms of rates. Furthermore, the phase diagrams for roundabout as well as traffic circle are constructed. It has turned out that the phase diagrams consist essentially of two phases namely free flow and jamming. It is noted that the typology of the phase diagrams of the roundabout is not similar to it in the traffic circle. Furthermore, we have compared the performance of the two systems in terms of the geometrical properties and the number of entry points. [ABSTRACT FROM AUTHOR]

Optimal allocation of vaccine doses is a major challenge faced by the health authorities especially in the case of an ever-growing pandemic expansion and a limited supply availability. Based on a spatio-temporal compartmental virus propagation model applied to the case of SARS-CoV-2 virus, we investigate a layered vaccine allocation strategy for the subpopulations of a given country or a geographical region based on the prevalence of susceptible individuals as a prioritization metric. Our findings show that a relaxed layered allocation prioritization, where a maximum of regions benefit from vaccine doses is more effective in controlling the epidemic than a strict prioritization, focused only on the few most prioritized regions. These results are consistent among different vaccine rollout speeds for various limiting values of the priority list. [ABSTRACT FROM AUTHOR]

We have studied the effect of quantum transverse anisotropies on the multilayer transition and magnetic properties of a spin-3/2 Blume–Capel model of a system formed by two magnetic multilayer materials, of different thicknesses, separated by a nonmagnetic spacer of thickness and RKKY interaction. Using mean-field theory, it is found that the multilayer magnetic order–disorder transition temperature depends strongly on the value of the transverse anisotropy. The multilayer transition temperature decreases when increasing the transverse anisotropy. Furthermore, there exists a critical quantum transverse anisotropy Δ xL beyond which the separate transitions occur in the two magnetic layers. The critical transverse anisotropy Δ xL increases on increasing the magnetic crystal field and/or the thickness of the magnetic multilayers  N. On other hand, the Δ xL decreases on increasing the Fermi level and/or the nonmagnetic thickness  M. [ABSTRACT FROM AUTHOR]

In this paper, we have investigated two observed situations in a multi-lane road. The first one concerns a fast merging vehicle. The second situation is related to the case of a fast vehicle leaving the fastest lane back into the slowest lane and targeting a specific way out. We are interested in the relaxation time , i.e., which is the time that the merging (diverging) vehicle spends before reaching the desired lane. Using analytical treatment and numerical simulations for the NaSch model, we have found two states, namely, the free state in which the merging (diverging) vehicle reaches the desired lane, and the trapped state in which diverges. We have established phase diagrams for several values of the braking probability. In the second situation, we have shown that diverging from the fast lane targeting a specific way out is not a simple task. Even if the diverging vehicle is in the free phase, two different states can be distinguished. One is the critical state, in which the diverging car can probably reach the desired way out. The other is the safe state, in which the diverging car can surely reach the desired way out. In order to be in the safe state, we have found that the driver of the diverging car must know the critical distance (below which the way out will be out of his reach) in each lane. Furthermore, this critical distance depends on the density of cars, and it follows an exponential law. [ABSTRACT FROM AUTHOR]

Connected vehicles (CVs) have led to innovative changes in the transportation field. In this wise, an extended CA model was established incorporating the CVs and regular vehicles to investigate a roundabout traffic flow under the open boundary condition. The throughput and the phase diagrams of the system in the ( α 1 , α 2 ) area is constructed in both cases: with and without CVs. The density profile and the capacity are also calculated. The simulation findings show that CVs presentation changes the traffic dynamics, enhancing roundabout capacity in accordance with the CVs penetration rate. Furthermore, it is found that roundabout size plays a dominant role in its performance where it suggests that the midsized roundabouts operate more optimally. Another relevant aspect is the short sized of Splitter Island shows a better performance. Moreover, the traffic dynamics is negatively (resp. positively) correlated to the probability of displaying indicator P ind as well as the probability of aggressive driving behavior of regular vehicles (resp. the cooperation probability P cop ). [ABSTRACT FROM AUTHOR]

The Monte Carlo (MC) simulation is used to study the magnetic properties of a spin-1/2 Ising antiferromagnetic film sandwiches between two ferromagnetic surfaces. The influence of different exchange surface interactions on the phase diagram of such a film is studied. In the ordered phase, it is found that the antiferromagnetic layer of the film can change in ferromagnetic or ferrimagnetic phases, depending on the values of the surface, the perpendicular and the bulk magnetic couplings. Moreover, the sublattice magnetizations are computed as a function of temperature for a film of thickness n=10 and fixed values of magnetic couplings. [ABSTRACT FROM AUTHOR]

We investigate quantum key distribution where information is carried by a d-level optical quantum system. The sender uses the mutually unbiased bases generated from the phase states of the quantum system. We consider the effects of several intercept and resend attacks. We derive explicitly the mutual information between the legitimate parties as well as the mutual information between the sender and the different eavesdroppers in the communication channel. We discuss the security of the cryptographic scheme and present some numerical analysis. [ABSTRACT FROM AUTHOR]

Using mean-field theory, we have studied the effect of quantum transverse field on the magnetic properties and multilayer transitions in the spin-3/2 Blume-Capel model with RKKY interaction. The system is formed by two magnetic multilayer materials, of different thicknesses, separated by a non magnetic spacer of thickness M. It is found that there exist critical transverse fields above which the multilayer transitions occur. This critical value decreases when increasing the thickness of the nonmagnetic spacer M. Phase diagram is established in different plane of space parameter. [ABSTRACT FROM AUTHOR]

We studied the effect of the Ruderman-Kittel-Kasuya-Yosida interaction on the multilayer transition and magnetic properties of spins-3/2 and 1/2 Blume-Capel model in the bilayer separated by a non-magnetic spacer of thickness (d), by using mean-field theory and Monte Carlo simulation. It is found that the multilayer transition temperature depends strongly on the thickness of the non-magnetic layer and the crystal field. Furthermore, the critical thickness of the non-magnetic spacer above which the two magnetic multilayers transit separately depends on the Fermi level and the absolute temperature. [ABSTRACT FROM AUTHOR]

We propose a traffic flow model which takes into account the disorder in the length and the maximal speed of cars. Using cellular automaton model in parallel dynamics we have studied the behavior of traffic flow, especially the condition of formation (active phase) and the dissociation (absorbing phase) of platoons. It is found that the transition from active to absorbing phase depend on the length of the slow vehicles L2. Indeed, the transition is discontinuous for L2 = 1 and continuous when L2 > 1. In the later case, the critical exponent is calculated near the transition density, and the space-time diagram shows the presence of the two phases. Furthermore, we have found that the fundamental diagram exhibit a plateau which depend on the size of the system. [ABSTRACT FROM AUTHOR]

Abstract: A Monte Carlo (MC) simulation has been used to study the magnetic properties of an antiferromagnetic surface which is coupled ferromagnetically to a ferromagnetic layer. The influence of different exchange interactions on the phase diagram of the surface has been investigated. We have found that in the ordered phase, depending on the values of the exchange interactions, the antiferromagnetic surface can change to ferromagnetic or ferrimagnetic phases. Furthermore, in the case of a bilayer surface, the layering antiferromagnetic–ferromagnetic or ferrimagnetic transitions occur. [Copyright &y& Elsevier]

The effects of some disorders, on the traffic flow behavior, are studied numerically. Especially, the effect of mixture of vehicles of different velocities and/or lengths, the effects of different drivers reactions, the position and the extraction rate of off-ramp in the free way. Using a generalized optimal velocity model, for a mixture of fast and slow vehicles, we have investigated the effect of delay times τ f and τ s on the fundamental diagram. It is Found that the small delay times have almost no effect, while, for sufficiently large delay time τ s , the current profile displays qualitatively five different forms, depending on τ f , τ s and the fractions f f and f s of the fast and slow cars, respectively. The velocity (current) exhibits first-order transitions at low and/or high densities, from freely moving phase to the congested state, and from congested state to a jamming one, respectively. The minimal current appears in intermediate values of τ s . Furthermore there exist, a critical value of τ f above which the meta-stability and hysteresis appear. The effects of disorder due to drivers behaviors have been introduced through a random delay time τ allowing the car to reach its optimal velocity traffic flow models with open boundaries. In the absence of the variation of the delay time Δτ, it is found that the transition from unstable to meta-stable and from meta-stable to stable state occur under the effect of the injecting and the extracting rate probabilities α and β respectively. Moreover, the perturbation of the traffic flow behavior due to the off-ramp has been studied using numerical simulations in the one dimensional cellular automaton traffic flow model with open boundaries. When the off-ramp is located between two critical positions i c1 and i c2 the current remains constant (plateau) for β0 c1 < β0 < β0 c2, and the density undergoes two successive first order transitions: from high density to plateau current phase and from average density to the low one. In the case of two off-ramps, these transitions occur only when the distance between ramps, is smaller than a critical value. [ABSTRACT FROM AUTHOR]

Tollbooths are used to collect tolls and to control traffic flow. However, the presence of these tollbooths will slow down traffic, especially in heavily traveled roads. As a consequence, drivers and goods will spend more time and fuel waiting in a long queue. Unfortunately, there are a few papers in the literature, which have been addressed the effect of tollbooths on the traffic flow; whereas in this paper is, the properties of traffic flow inside the tollbooths are investigated. The proposed cellular automaton traffic model, with open boundaries, is based on some changing lane rules, which are inspired on the situations inside the toll plaza. The vehicles enter the plaza with an injecting rate α, and they leave with an extracting rate β, which is inversely proportional to the time service Tw. The simulation results show the existence of three phases in the phase diagram (α, β), namely: the low density phase, the congested phase, and the jamming phase. Furthermore, it is found that the vehicles does not spend the same time Tm in the plaza, even if they have the same time service. This analysis states clearly that the existence of the congested phase and the fluctuation Tm are due to the non-zero values of the probability P of changing the lane. Such phenomena disappear when P = 0, i.e., the drivers move without changing their lane. In other words, the human behavior (spontaneous changing lanes) is responsible for the congestion observed in the tollbooth. [ABSTRACT FROM AUTHOR]

A simple 2D model of deformable vesicles tumbling in a shear under flow is introduced in order to account for the main qualitative features observed experimentally as shear rates are increased. The simplicity of the model allows for a full analytical tractability while retaining the essential physical ingredients. The model reveals that the main axes of the vesicle undergo oscillations which are coupled to the vesicle orientation in the flow. The model reproduces and sheds light on the main novel features reported in recent experiments [M. Mader et al., Eur. Phys. J. E. 19, 389 (2006)], namely that both coefficients A and B that enter the Keller-Skalak equation, dψ/dt = A+Bcos(2 ψ) (ψ is the vesicle orientation angle in the shear flow), undergo a collapse upon increasing shear rate. [ABSTRACT FROM AUTHOR]

Abstract: The effect of a random surface field, within the bimodal distribution, on the layering transitions in a spin- Ising thin film is investigated using Monte Carlo simulations. It is found that the layering transitions depend strongly on the concentration p of the disorder of the surface magnetic field, for a fixed temperature, surface and external magnetic fields. Indeed, the critical concentration at which the magnetisation of each layer k changes the sign discontinuously, decreases with increase in applied surface magnetic field, for fixed values of the temperature T and the external magnetic field H. Moreover, the behaviour of the layer magnetisations as well as the distribution of positive and negative spins in each layer, are also established for specific values of , H, p and temperature T. [Copyright &y& Elsevier]

Abstract: We study the substrate inhomogeneity effect on the wetting of a spin-1/2 Ising ferromagnetic film in an external magnetic field H, using Monte Carlo simulations. It is found that the inhomogeneity leads to the formation of clusters of positive and negative spins in each layer. However, depending on the values of H, for a fixed surface magnetic field H s , each layer exhibits three different phases; totally wet, non wet and partially wet. In the latter case, we show the existence of three distinct configurations namely: A configuration in which the layer is partially wet with a total disconnection between clusters PWTD; a configuration in which the layer is partially wet with a partial disconnection between clusters PWPD; the configuration in which the layer is partially wet and the clusters are totally connected PWTC. Furthermore, we show that an increase of H s values breaks the bonds connecting some clusters of the phase PWTC which leads to an expansion of the PWPD region. On the other hand, the frequency distribution and the average size of clusters are investigated in the PWTD region for fixed values of temperature T, H s and H. Moreover, we show the existence of 3D-islands resulting from the formation of islands in each layer. [Copyright &y& Elsevier]

We have numerically investigated the effect of the delay times τf and τs of a mixture of fast and slow vehicles on the fundamental diagram (the current-density relation) of the optimal velocity model. The optimal velocity function of the fast cars depends not only on the headway of each car but also on the headway of the immediately preceding one. It is found that the small delay times have almost no effects, while, for sufficiently large delay time τs, the current profile displays qualitatively five different forms, depending on τf, τs and the fractions df and ds of the fast and slow cars, respectively. The velocity (current) exhibits first-order transitions at low and/or high densities, from freely moving phase to the congested state, and from congested state to a jamming one, respectively. The minimal current appears in intermediate values of τs. Furthermore, there exist a critical value of τf above which the metastability and hysteresis appear. The spatial-temporal traffic patterns near the congested-jamming first-order transition is also presented. [ABSTRACT FROM AUTHOR]

The effect of the random quantum transverse field Ω on the tricritical behavior of the spin-1 Blume–Emery–Griffiths (BEG) model is studied using an effective field theory. It is found that the tricritical behavior depends on both the biquadratic interaction K, single-ion anisotropy Δ and the concentration p of the disorder of Ω. Indeed, there exists a special value p1 of the probability p below which the tricritical behavior disappears. In addition, at sufficiently low temperatures, the system exhibits long-range order accompanied by the tricritical behavior below a special value p2 of the probability p. [ABSTRACT FROM AUTHOR]

Presents a study on the effect of mixture lengths of vehicles on the asymmetric exclusion model. Use of numerical simulations for both open and periodic boundaries in deterministic parallel dynamics; Details on the model applied in the study; Discussion on the case of one and two entries.

Examines the effects of open boundaries on the dynamical behavior of optimal velocity traffic flow model with a delay time allowing the car to reach its optimal velocity using numerical simulations. Mathematical description of the traffic flow model; Analysis of the critical value of traffic flows; Examination of the space-time evolution for various values of extracting rate probability.

The effect of the transverse field Ω on bulk melting and layering sublimation transitions of a spin-1 Blume–Emery–Griffiths (BEG) model is studied using the mean field theory. It is found that there exists a critical value of the transverse field Ωl above which a sequence of layering sublimation occurs before melting bulk transition.Ωl depends on the value of temperature T and chemical potential Δ. Indeed, Ωl decreases with increasing temperature and/or decreasing chemical potential. Phase diagrams in the (Ω–T) and (Ω–Δ) planes are established. However, the increase of the transverse field favours the layering sublimation and bulk melting transitions. Moreover, the (Ω–T) phase diagrams show that the sequence of the critical end points go to the roughness transverse field ΩR and the roughness temperature TR which depend on the value of the chemical potential. Hence, ΩR increases and TR decreases when Δ increases. The profiles of densities and magnetizations as a function of the chemical potential, transverse field and the depth of the film are calculated. [Copyright &y& Elsevier]

The effects of alternating transverse fields Ωa and Ωb on the critical behavior of an alternating spin-1 Ising superlattice are studied within an effective field theory with a probability distribution technique that accounts for the single-site spin correlation. Critical temperatures are calculated as a function of the thickness of the superlattice and the strength of the transverse field. Depending on the values of the transverse fields Ωa and Ωb, the critical temperature can increase or decrease with increasing the thickness of the film, such result is not obtained in the uniform transverse field case (Ωa = Ωb). Furthermore, for each thickness L of the film, a long range ordered phase persist at low temperature for selected values of the transverse field Ωa and arbitrary values of Ωb. The effects of interlayer and intralayer exchange interactions are also examined. [Copyright &y& Elsevier]

Doping techniques are commonly utilized to effectively modify the physical properties of a desired compound. In this study, we employed the first-principles DFT calculations with a GGA + TB-mBJ approach as implemented by the Wien2k code, by investigating the effects of oxygen group element concentrations on the structural, electronic, and optical properties of the perovskite substance SrTiO 3. We calculated the formation energies of each doped structure to assess the viability of synthesis. The band gap is equal to 1.355 eV, 0.653 eV, and 0.632 eV for 12.5 % S, Se, and Te doped SrTiO 3 , respectively. For the pure SrTiO 3 , the band gap is 2.584 eV. According to our findings, raising the chalcogen concentrations resulted in a considerable decrease in band gaps and an improvement in the ability to absorb light in the visible range (380–790 nm), exceeding 105 cm−1 for Te doped SrTiO 3 (STO). At zero frequency, the dielectric constant was found (ε1 (0)) to be 4.432 for SrTiO 3 pure and 6.332 for SrTiO 3 doped with Te (12.5 %) in GGA-PBE and (ε 1 (0)) = 4.432 and 12.217 for GGA + mBJ. The optical conductivity of SrTO 3 doped with Te is determined to be 0.322 * 104 /Ω. cm , in comparison to a value of 0.377 * 104/Ω. cm for mBJ. Our research revealed that raising the chalcogen concentrations significantly enhanced the electrical conductivity, as predicted, along with improvements in optical conductivity and reflectivity. SrTiO 3-x Y x (Y = S, Se, or Te) represents one of our quaternary alloys, demonstrating substantial potential as a promising material for advanced photovoltaic and solar cell applications. Our findings revealed that the doped materials exhibited significantly high absorption rates and productivity. We also examined additional optical parameters, including optical band gap, Urbach energy, and optical conductivity. [ABSTRACT FROM AUTHOR]

The structural, electronic, magnetic, magnetocaloric, and thermoelectric properties of the SrXO3 (X = Mn and Fe) perovskite compounds were investigated using first-principles calculations. It was observed that the SrXO3 compounds are G-anti-ferromagnetic perovskites with partial magnetic moment with a value of 2.7 μ B and 2.4 μ B for Mn-3d and Fe-3d orbitals for SrMnO3 and SrFeO3, respectively. Moreover, by using Monte Carlo simulation (MCs) combined with the Metropolis algorithm, the calculated coupling interactions between the magnetic atoms Mn–Mn and Fe–Fe are J 1 Mn = 5. 1 7 meV and J 2 Mn = − 0. 6 meV for SrMnO3, J 1 Fe = 3. 4 4 meV and J 1 Fe = − 0. 4 meV for SrFeO3, respectively. Furthermore, a significant magnetocaloric effect (MCE) was observed around the Néel temperature of T N Mn = 2 6 0 K (for SrMnO3) and T N Fe = 1 3 4 K (for SrFeO3), and the maximal simulated magnetic entropy and relative cooling power values of all the studied compounds are found to be 100 J/kg (for SrMnO3) and 110 J/kg (for SrFeO3), respectively, with an applied magnetic field of H = 4. 0 T. These results are in complete agreement with the experimental results and more specifics than other theoretical calculations. Hence, SrXO3 compounds are considered promising candidates for magnetic refrigeration at low temperature. [ABSTRACT FROM AUTHOR]

The electronic and thermoelectric properties of the perovskite LaCoO3 compound were studied using first-principles calculations. However, Monte Carlo calculation (MC) combined with the Metropolis algorithm, calculates the magnetic and magneto-caloric properties. The partial moment of the Cobalt atom (Co) and exchange coupling interactions for Co-d orbital at high spin (HS: S = 2), show values µCo = 2.54${\rm \mu }_{B\; \comma }J_1^{{\rm Co}-{\rm Co}} = 2.39\; {\rm meV} \comma \; J_2^{{\rm Co}-{\rm Co}} = 0.9\; {\rm meV}\comma$μB,J1Co−Co=2.39meV,J2Co−Co=0.9meV, respectively. The calculated Curie temperature value (TC) is 100 K, which agrees with the experimental results, such as the LaCoO3 metallic perovskite has a secondary Ferro-Para magnetic transition around TC. The evolutions in magnetic and magnetocaloric (MEC) properties with external magnetic fields were also studied. Finally, thermoelectric properties are examined. [ABSTRACT FROM AUTHOR]

The objective of this study was to investigate the impact of connected and autonomous vehicles (CAVs) on traffic flow under various parameters. For this purpose, we propose a mixed CAV and conventional vehicle (CV) model to investigate a bidirectional two-lane traffic flow under the periodic boundary condition. The traffic flux and the phase diagrams of the system in the ( ρ 1 , ρ 2 ) area are constructed in both cases: with and without CAVs. The overtaking frequency is also calculated. The simulation findings show that the traffic capacity is greatly enhanced with the increase in the CAV penetration ratio. Owing to the cooperative driving strategy, with the increase in penetration ratio of the CAV, the portion of smooth overtaking is boosted. Furthermore, it is found that the traffic throughput is positively correlated to the speed limit of the fast vehicle where the flux increases as V max − F increases. Also, even if there is a low rate of slow moving vehicles in the system, it will have an appreciable and a significant negative influence. [ABSTRACT FROM AUTHOR]

One of the most important areas of materials science research is the creation of novel materials for energy conversion and storage. Computational simulations have become a potent tool for anticipating novel material characteristics and speeding up the discovery process in recent years. In this article, we present a computational investigation of the structural, electronic, and optical properties of double perovskites Cs 2 KInX 6 (X = Br, Cl, and I), with a focus on their potential applications in energy conversion. The purpose of this work is to accomplish a comparative analysis of novel optoelectronic lead-free halide double perovskites. The Cs 2 KInX 6 double perovskites compounds display direct semiconducting behavior with optical bandgap energies values of about 2.60, 3.60, and 1.67 eV for Cs 2 KInBr 6 , Cs 2 KInCl 6 , and Cs 2 KInI 6 , respectively. The results obtained underscore the remarkable characteristics of the studied compounds. Notably, a substantial absorption coefficient exceeding 106 cm−1 in the ultraviolet range and a notable absorption coefficient surpassing 105 cm−1 in the visible spectrum were observed. The obtained optoelectronic characteristics that have been indicate that Cs 2 KInX 6 compounds hold great potential for usage in solar cell applications. [ABSTRACT FROM AUTHOR]

In this paper, we examine the impact of vehicles executing a full turn or U-turn in a single-lane roundabout system using a cellular automaton model. We investigate how increasing the number of these U-turning vehicles affects traffic flow characteristics and energy dissipation. Our findings reveal that as the prevalence of U-turning vehicles rises, the phase diagram undergoes significant changes; the maximum current phase expands, detrimentally impacting the free flow and congestion phases, while giving rise to a jamming phase. This shift results in a gradual increase in capacity at circulating lanes and a steady decline at entry/exit lanes. We also explore the role of aimless vehicles — those circulating without a fixed destination. As the proportion of such vehicles augments, it fosters an enlargement of the maximum current phase at the expense of the free flow and congestion phases. Furthermore, these vehicles influence energy dissipation across the three lanes of a roundabout. Significantly, we elucidate that variations in the percentage of these specific vehicular groups critically affect CO2 emissions. Our research unravels vital insights into optimizing roundabout management to enhance traffic flow and reduce environmental impact. [ABSTRACT FROM AUTHOR]

Researchers are working on perovskites for photovoltaic applications due to their low cost and excellent power conversion efficiency. Our investigation has focused on analyzing the effects of hydrostatic strain on the structural, electronic, optical and thermoelectric properties of CsSnBr3. The calculated structural properties and enthalpy of formation imply that these structures are stable under different strain conditions. Our investigation shows that the CsSnBr3 compound is a direct semiconductor with an electronic band gap of 1.272 eV, which can be tuned from 0.604 eV to 1.823 eV under different strain conditions. As the compressive strain increases, the light absorption spectrum of CsSnBr3 undergoes a red shift, causing a prolongation of the light absorption edge. The thermoelectric properties show that CsSnBr3 is a p-type semiconductor. Our findings indicate that the CsSnBr3 material is highly suitable for photovoltaic applications. [ABSTRACT FROM AUTHOR]

Novel Sillenites Bi25Fe(1−x)AlxO40 (x = 0.00, 0.20, and x = 0.50) have been synthesized using the SSR method. In this paper, the effect of Al-substitution on the physicochemical properties was performed. The X-ray diffraction analysis as well as both Raman and FT-IR spectroscopies indicate that all the elaborated materials have a bcc structure with the I23 space group. The increase of the cell parameters, the morphological features, and thus the decrease of the grain size with Aluminum content is also evidenced via the X-ray patterns and SEM microscopy. DSC measurements highlighted the occurrence of various phenomena related to both structural and dielectric features. The temperature dependence of electrical conductivity and the deduced activation energies pointed to the effect of temperature on the conduction process. The impedance analysis on the samples confirms the onset of relaxation phenomenon in the sample with semiconducting behavior. Furthermore, an AFM-Paramagnetic transition for x = 0.00 and 0.20, with Neel temperatures of 268 and 265 K, respectively. Otherwise, paramagnetic behavior is observed for x = 0.50. The optical measurements make these materials suitable candidates for photocatalysis and optoelectronic applications. [ABSTRACT FROM AUTHOR]

The manuscript explores the electromagnetic and magnetocaloric characteristics of the intermetallic compound Gd 2 Cu 2 C d. One of the key findings is that Gd2Cu2Cd possesses a magnetic moment of approximately 7.13 μB. The simulated magnetic properties illustrate a second-order phase transition from ferromagnetic (FM) to paramagnetic (PM) occurring at approximately 130 K. This material exhibits a substantial magnetocaloric effect (MCE) across various external magnetic field strengths. To be more specific, this transition occurs at an external magnetic field of 4.0 T, in particular, at an external magnetic field of 4.0 T, the extreme magnetic entropy change ( Δ S mag ) is measured at 3.58 J/kg.K, and the relative cooling power (RCP) reaches 28 J/kg. Notably, with an increase in the external magnetic field, the maximum value of ( ΔS mag ) increases significantly, and the Curie temperature ( T C ) shifts toward lower temperatures. These results suggest that Gd 2 Cu 2 Cd has significant potential for applications in magnetic refrigeration that leverage the magnetocaloric effect. [ABSTRACT FROM AUTHOR]

The main objective of many researches is to find an excellent reversible material for hydrogen storage applications under ambient conditions. The hydrogen adsorption on pure C 2 N-h2D shows an attractive result using density functional theory (DFT) calculations implemented with the van der Waals corrections, and ab-initio molecular dynamics (AIMD). A high adsorption energy up to - 0.3150 eV, the adsorption occurs through physisorption and no chemical bond is formed between the molecule and the C 2 N surface irrespective of the site of interaction, the migration process of H 2 molecule on the substrate was so easy due to the low activation energy which was found around 7.08 meV. The study shows large gravimetric capacity as well as volumetric capacity around 11.62 wt% and 117.20 g/l. Compared to the critical point of hydrogen (33.25 K), the desorption temperature (T D) was found to be around 229.23 K, which is considerably higher. The adsorption of 30H 2 molecules on C 2 N-h2D and the stability of the system was verified through AIMD simulations. Therefore, our material proved to be a promising candidate for hydrogen storage applications at room temperature. • The adsorption energy is around - 0.2849eV. • The gravimetric capacity up to 11.62 wt%. • The desorption temperature up to 229.23 K. • The activation energy about 7.08 meV. [ABSTRACT FROM AUTHOR]

Herein, the ground-state properties of the intermetallic compound NdPd and its magnetic observable curves as well as its magnetocaloric properties have been investigated using a combined Monte Carlo simulation and ab initio calculations. The calculated magnetic moment of Nd atom is 3.11 μB which is in agreement with the experimental one. Furthermore, it was established that the first two exchange couplings for Nd-Nd interactions present positive signs ( J 1 = 1.593 meV and J 2 = 0.358 meV), where both correspond to ferromagnetic interactions. In good agreement with recent experimental works, the simulation results revealed that the NdPd compound orders ferromagnetically at T c =16 K. It was moreover found that the isothermal magnetic entropy around the Curie temperature and the relative cooling power (RCP) in an applied magnetic field of 5 T are acceptable concurrence with those obtained in the laboratory. Besides, the good magnetocaloric properties of NdPd obtained here are quite convincing to predict that NdPd-based magnetic refrigeration can be considered a promising technology for cryogenic cooling systems within the range T < 20 K. [ABSTRACT FROM AUTHOR]

The manuscript explores the electromagnetic and magnetocaloric characteristics of the intermetallic compound Gd 2 Cu 2 C d. One of the key findings is that Gd2Cu2Cd possesses a magnetic moment of approximately 7.13 μB. The simulated magnetic properties illustrate a second-order phase transition from ferromagnetic (FM) to paramagnetic (PM) occurring at approximately 130 K. This material exhibits a substantial magnetocaloric effect (MCE) across various external magnetic field strengths. To be more specific, this transition occurs at an external magnetic field of 4.0 T, in particular, at an external magnetic field of 4.0 T, the extreme magnetic entropy change ( Δ S mag ) is measured at 3.58 J/kg.K, and the relative cooling power (RCP) reaches 28 J/kg. Notably, with an increase in the external magnetic field, the maximum value of ( ΔS mag ) increases significantly, and the Curie temperature ( T C ) shifts toward lower temperatures. These results suggest that Gd 2 Cu 2 Cd has significant potential for applications in magnetic refrigeration that leverage the magnetocaloric effect. [ABSTRACT FROM AUTHOR]

• Wood chips and pellets from lignocellulosic anaerobic digestion residues were tested. • Biochar and Syngas from oxidative pyrolysis were characterized. • Effect of air on oxidative pyrolysis was investigated. • Front propagation velocity and equivalence ratio were calculated. Compared to pyrolysis in an inert atmosphere, oxidative pyrolysis for biomass conversion is autothermal and decreases the concentration of tars in the produced gases. The aim of this work is to study a fixed bed reactor for oxidative pyrolysis on a laboratory scale with a capacity of 1.5 kg/h of lignocellulosic anaerobic digestion residues (Pellets-DR) at a temperature range of 600 °C and under a low specific airflow of 0.012 kg/m2.s. Wood chips (WC-P16F05) were used as a reference to evaluate the potential of Pellets-DR conversion to biochar and syngas using oxidative pyrolysis. Oxidative pyrolysis produced only 10% and 6% of tars on a fuel dry and ash-free basis for Pellets-DR and wood chips, respectively, which is equivalent to a concentration of 25 g/Nm3 and 38.6 g/Nm3 in gases. Ultimate and proximate analysis of biochar produced from both types of biomasses showed that the main element present was carbon in the case of wood chips (87.8%). However, carbon is present in only 48.33% of the biochar from Pellets-DR. The main difference between Pellets-DR and wood chips was also found in biochar's low heating value (LHV), which is estimated to be 31.9 MJ/kg for wood chips and 13.01 MJ/kg for Pellets-DR. The propagation of the oxidation zone was inversely proportional to biomass density, and it plays a key role during biomass oxidative pyrolysis; it was about 0.14 cm/min and 0.5 cm/min for Pellets-DR and wood chips, respectively. Air flux was the most important factor affecting the oxidation zone propagation velocity, but in this study, low values of air flux meant that changes in air flux did not have a significant effect on the yield and the composition of the products. Regardless of its high ash content, Pellets-DR may have the potential to be converted into biochar and syngas by oxidative pyrolysis. [ABSTRACT FROM AUTHOR]

The influence of poly(o-toluidine) (POT) interlayer as a hole transporting layer (HTL) and iodine doping on electrical properties of hybrid solar cells based on a mixture of didecyl-sexithiophène (2D6T) and nanostructured zinc oxide as blend donor/acceptor-active layer have been investigated. The sexithiophene 2D6T was synthesized by a chemical route through the oxidative coupling of the corresponding terthiophene derivatives, and the nanostructured ZnO powders were prepared by a one-pot solution route at ambient conditions. A series of ITO/(2D6T: nanostructured ZnO)/Al solar cells with and without POT interlayer were fabricated by successive deposition using the spin coating technic, and they are completed by thermal evaporation of aluminium circular contacts on the active layer. The non-linear dark current–voltage I(V) characteristics of these devices indicate a rectifying behaviour. The diode parameters were calculated from I(V) characteristics using the modified Shockley equation and discussed. On the other hand, I(V) characteristics measured under illumination are also presented, studied and compared. The short-circuit current (Isc) and open-circuit voltage (Voc) of solar cells are improved by the incorporation of the HCl-doped POT thin films and by iodine doping, provided that the iodine concentrations do not exceed 10%. [ABSTRACT FROM AUTHOR]

The purpose of this study is to conduct theoretical investigations on the electronic, structural and magnetic properties of lithium niobate (LiNbO3) doped with different concentrations of the transition metal chromium (Cr). All properties of LiNb1−xCrxO3 compounds (x = 0.25, 0.50 and 0.75) are achieved with spin-polarized density functional theory by the GGA-PBE and the TB-mBJ approximations. To ensure the stability of the LiNb1−xCrxO3 quaternary alloy in the ferromagnetic state, the total energy released from the optimized structure and the defect formation energy were calculated. The classical Heisenberg model estimated the Curie temperature of the compounds. The material studied exhibits a 100% spin-polarized semi-metallic ferromagnetism behaviour. In all compounds, the data of the magnetic moment demonstrated that the chromium impurity atom is the most important source by comparison with the Nb and Li, which have minor contributions. In addition, the magnetic moment of the Cr atoms decreases with doping; this comes from the p–d hybridization between the Cr-3d and O-2p states. The half-metal gap (GHM), the most important factor in spintronics applications, was also calculated. In addition, to assess the effects of the exchange separation process, the crystal field separation energy, the exchange separation parameters, and the exchange constants N0α, N0β, and ΔEC, ΔEV are predicted. [ABSTRACT FROM AUTHOR]

Abstract On the basis of spin density functional calculation, the electronic and magnetic properties of ZnSe doped with double impurities Zn 1-2x Fe x Co x Se (x = 0.05) are studied using the Korringa-Kohn-Rostoker coherent potential approximation (KKR-CPA) method within the local density approximation (LDA). The half-metallic ferromagnetic nature of (Fe, Co) doped ZnSe is investigated. Therefore the electronic structure and magnetic properties of Zn 1-2x Fe x Co x Se exhibit a half-metallic ferromagnetic character; the stability of ferromagnetic (FM) compared to the disorder local moment (DLM) has been discussed. Our calculation is supported by Monte Carlo simulations (MCS) based on the heat bath algorithm. We have examined the effects of system size L on magnetization, specific heat and magnetic susceptibility. The spin density functional calculation results are in good agreement with the literature, especially for 5% of (Co, Fe) each, which gives the most interesting results. Highlights • The magnetic properties of ZnSe doped with double impurities has been investigated. • The half-metallic ferromagnetic nature appears in doped ZnSe with (Fe, Co). • The effect of size lattice ZnSe is studied. • Monte Carlo simulation is used. [ABSTRACT FROM AUTHOR]

Abstract The crystal field effect on the layering transitions of the spin-1 Blume–Capel model is studied, in the presence of external and surface magnetic field, using Monte Carlo simulations. The ground state phase diagrams were determined analytically. We showed that existing phases are strongly dependent on the surface and the bulk crystal field. At finite temperature, the phase diagrams have been examined in detail. In particular, different phases are found to be separated for different configurations. To complete this study, we discuss and interpret the behavior of the magnetizations and the quadrupolar moments. Highlights • We have studied the effect of the crystal field on the layering transitions. • Using Monte Carlo simulations, we study this system. • We have elaborated the ground state phase diagrams of the system. • A low temperature values, we have determined the magnetizations. [ABSTRACT FROM AUTHOR]

In this study, we performed extensive Monte Carlo simulations to comprehensively analyze the magnetic properties of a single-layer MXene-like lattice. Our investigation involved the exploration of transition temperatures and the behavior of hysteresis cycles, all influenced by a series of key physical parameters. Additionally, we carefully mapped the magnetization as a function of temperature and crystal field, introducing variations in the exchange coupling to unveil their impact on the transition temperature. Furthermore, we investigated the behavior of hysteresis loops, complexly dissecting their responses to changes in exchange coupling, temperature, and crystal field. Significantly, our results highlight the central role of the crystal field in the formation of magnetization plateaus, thus providing promising avenues for applications in nanotechnology and advanced memory storage systems. [ABSTRACT FROM AUTHOR]

This work intends to compare the structural, morphological and frequency (20 Hz–1 MHz) and temperature (30 °C–300 °C) dependent dielectric properties of BaSnO 3 ceramics and thin films. The BaSnO 3 solution was prepared by sol-gel method. Thin films were deposited by spin-coating on Pt/Ti/SiO 2 /Si substrates. The ceramics were prepared with powder derived from the sol-gel solution. X-ray diffraction spectra of ceramics and thin films showed a pure BaSnO 3 phase with a cubic structure. The effect of sintering temperature was studied to obtain a good crystalline quality of BaSnO 3 ceramics. SEM photos were taken both on ceramics and films. An average roughness of 1.8 nm measured by AFM on films clearly indicates the high quality of the film surface. The phase purity and chemical composition were further confirmed by using energy dispersive X-ray spectroscopy. The room temperature dielectric constant (ε′) was found to be ∼17 and 13 at 1 MHz for ceramics and thin films, respectively. Moreover, quite low dielectric loss tangent values were obtained both for ceramics and thin films. The dielectric study in function of temperature showed maximums on the ε' evolution at 230 °C and 220 °C, for ceramic and thin film, respectively. XRD patterns taken at different temperatures have shown a stable cubic structure of BaSnO 3 powder. This structural stability clearly demonstrates that peaks observed on the temperature dependent plots are only related to dielectric phenomena, which have been described. AC conductivity showed an influence of electrically activated charge carriers, both for ceramics and thin films. The present study also signifies that the dielectric properties of BaSnO 3 ceramics can be successfully replicated on thin films by a facile and cost-effective deposition method. [ABSTRACT FROM AUTHOR]