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Stochastic cellular automata for rock-paper-scissors games are related to Lotka-Volterra model. Simulations are usually performed by two methods local and global interactions. It is well known that the population dynamics with local interaction is stable, where all species coexist. In contrast, global interaction leads to extinction. So far, theories such as mean-field theory and pair approximation have been presented, but they never explained the stable dynamics in local simulation. In the present article, we apply effective medium approximation (EMA) which has been developed in Physics. The effective medium is determined in a self-consistent way. The EMA theory well predicts the stability of population dynamics. Moreover, it fairly explains the aggregation of each species observed in the stationary state. [ABSTRACT FROM AUTHOR]

• Proposed a method for multi-axis random vibration topology optimization. • Enhancing vibration resistance and extending life during the topology phase. • Prompting the structure to add load-bearing paths to resist random vibration loads. • Guiding the topology towards forming a vibration-resistant structure. • Expanding HCA into the field of random vibration performance topology optimization. Considering the lack of effective solutions for multi-axis random vibration topology optimization problems, and recognizing that multi-axis random vibration excitation is the most common loading conditions experienced by structures during their operational life, this paper proposes a multi-objective topology optimization method for multi-axis random vibration. By combining Hybrid Cellular Automata (HCA) and Analytic Hierarchy Process (AHP), this method aims to enhance the vibration resistance of structures and extend their fatigue life during the topology optimization phase. To validate the effectiveness and engineering practicality of this method, two engineering cases were designed: a cantilever beam case and an automotive steering knuckle case. Multi-objective topology optimization were conducted with objectives including mass, stiffness, and vibration intensity metric (root-mean-square stress). The two cases demonstrate that the control group's topology model exhibits weaker resistance to random vibrations and shorter fatigue life. In contrast, the validation group's topology model introduces an additional load path near the excitation point, effectively dissipating the impact of vibration excitation. This enhances the structure's vibration resistance and significantly extends its fatigue life. [ABSTRACT FROM AUTHOR]

• A pedestrian-vehicle coupling model with high simulation accuracy is proposed. • Six phase regions were acquired from the heterogeneous traffic phase diagram. • Obtained the difference between the fundamental diagram of heterogeneous and homogeneous traffic. • Tighter speed limits and wider sidewalks can reduce traffic conflicts. In urban streets, the intrusion of pedestrians into the motorway will pose a considerable challenge. However, modelling mixed pedestrian-vehicle traffic scenes is difficult. Pedestrians and vehicles have different motion characteristics and spatial dimensions, so it is hard to carry out unified modelling, and there are few related studies. This paper combines the multi-grid cellular automata model to explore these scenes to connect the vehicle and pedestrian models. An Improved Kerner-Klenov-Wolf (IKKW) model and a pedestrian motion model considering Time-To-Collision (TTC) are proposed, in which the spatial motion of a vehicle and a pedestrian is uniformly updated horizontally and longitudinally. The preliminary analysis of the model shows that it has high simulation accuracy. Applying the model to the simulation of real-life situations, research results reveal the impact of pedestrian intrusion behavior on traffic and the changes in vehicles' speed and flow rate caused by pedestrian intrusion behavior. The fundamental diagram of pedestrian-vehicle heterogeneous traffic shows significant differences, reflecting the impact of pedestrian intrusion on the state of traffic flow, and exposes six phase regions of pedestrian-vehicle mixed traffic flow. Moreover, this paper analyzes the conflicts between pedestrians and vehicles under different speed limits and sidewalk widths, showing that lower speeds and wider sidewalks can effectively reduce the frequency of pedestrian-vehicle conflicts. The peak conflicts' frequency when the vehicles' speed limit is 60.48 km/h exceeds three times that when the speed limit is 30.24 km/h. The cellular automata model proposed in this paper provides a good direction and idea for studying mixed traffic flow and has high scalability. [ABSTRACT FROM AUTHOR]

• The model treats the frost layer as a heterogeneous porous medium. • This model was validated with some experimental data in the literature. • A multistep ascending growth pattern is found for both frost thickness and porosity. • The higher the frost porosity is, the lower the effective frost thermal conductivity is. The frost formation process is involved with many factors which lead to complex morphology. A two-dimensional model to simulate the early-stage frost formation on a cold flat plate is proposed in this paper based on the finite difference and cellular automata method. The concentration diffusion equation is used to constrain the diffusion of water molecules and the mass transfer equation is applied to relate the frost growth to the water vapor concentration and temperature. Furthermore, the temperature distribution during the growth process is obtained by solving the energy conservation equation. With the simulation, a heterogeneous porous medium consisting of ice crystals and air can be obtained and treated as a whole. Then, the physical properties of the frost layer like the frost thickness, the frost porosity and the effective thermal conductivity are calculated and analyzed. Results show that temperature is relatively uniform in the region where ice crystals are concentrated, and the frost surface temperature increases with the frost thickness as the frost grows. A multiple-step ascending growth pattern is observed both for the frost thickness and the frost porosity. The effective thermal conductivity of the frost layer correlates closely with the frost porosity and a higher frost porosity value results in lower thermal conductivity. Besides, the initial crystal nuclei distribution has a great influence on the morphologies of the frost layer, while the initial water vapor supersaturation has more impact on the growth speed of the frost thickness. [ABSTRACT FROM AUTHOR]

This paper presents a very fast numerical approach to simulate microstructures resulting from melt pool solidification including growth competition of columnar dendritic grains, and equiaxed grains nucleated from the melt. To reduce computation time, the key contribution is the development of an upscaling strategy, which instead of considering each dendrite individually consists in defining an average solidification front based on physically-informed dendritic growth velocity. The proposed approach also relies on dendritic preferred growth direction, and favorably oriented grain criterion to determine which grain survives the competition. To significantly reduce the total number of degrees of freedom Voronoi tessellations are used instead of regular grids for numerical implementation. Indeed, 3D regular grids typically leads to N 3 degrees of freedom while Voronoi tessellations lead to only 3 N , which dramatically reduces computation cost. This work is therefore a high-throughput approach enabling large data set generation to explore statistical features of microstructures with respect to melt pool properties. Results have been compared to experimental data, and to phase field and cellular automaton simulations in 2D only. Simulated microstructures are similar as those obtained with cellular automaton. Comparisons in 3D are left for future work. In addition, a convergence analysis is provided for 3D simulations, with thermal conditions corresponding to metal additive manufacturing to demonstrate how the present work can be used in practice. [Display omitted] [ABSTRACT FROM AUTHOR]

Cellular automata (CA) based models are practical tools to simulate the spatiotemporal landscape evolution induced by the land use/-cover change (LUCC). Existing models are struggling to comprehensively handle the spatiotemporal driving relationships amid the nonlinear LUCC process. Besides, the landscape patterns are not considered in most models, making them struggled to support the development strategies. Aiming at overcoming these obstacles, a novel land use/-cover change model concerning spatiotemporal dependency and properties related to landscape evolution (STAPLE) is proposed in this paper. A potential generating module establishing the nonlinear spatiotemporal driving relationship and a spatial allocating module employing a landscape-based CA are integrated for realistic LUCC simulations. As a case study, the proposed model is applied in Zhengzhou, China to assess its performance. It is indicated that the STAPLE model achieves a higher simulation accuracy, and the landscape properties are effectively manipulated. It provides a reproducible tool for policy-makers to explore a low-ecological-risk landscape under different future scenarios and achieve sustainable developments. • Propose an LUCC model concerning spatiotemporal dependency and landscape evolution. • Control the spatial evolution of landscape using a novel CA algorithm. • Promote accuracy by employing ST-CNN to assimilate the latent spatiotemporal dependency. • Provide a reproducible tool for policy-makers to achieve sustainable development. [ABSTRACT FROM AUTHOR]

• A prediction model of grain strain variations due to a specific neighborhood is proposed based on FE simulation observations. • A Cellular Automaton (CA) model is developed using this model and the approximations proposed in Part 1. The methodology to identify the model parameters and the model algorithm are fully described. • Studied polycrystals are represented by a regular structure (Kelvin structure) where all grains are of identical shape and size. • Both CA and FE polycrystalline aggregate stress fields predictions show very close results, but with a really shorter amount of CPU time for the CA model. • Using the quickness of the CA model, orientations causing stress concentrations were easily identified and have shown in the worst scenario to generate in a grain a resolved shear stress concentration twice more significant than for any other grains of the aggregate, without showing any different macroscopic behavior nor crystallographic texture. This paper presents the development of a Cellular Automaton (CA) capable of describing polycrystalline structures heterogeneous behavior in the elastic domain. Based on Eshelby's inclusion problem, this model is the first step to a better consideration of heterogeneities in polycrystals by including the neighborhood effect in grain's behavior. Neighborhood effects have been defined, quantified, and approximated from observations made in the first of this two-part paper, using finite element method (FEM). Considering these approximations, and based on FEM simulations results, an analytical model of the neighborhood effect was proposed in the present paper on which the CA model was built. As a first step in the model development, a regular aggregate structure (Kelvin structure) is used where grains are considered spherical and having identical size. The stress field predictions obtained with the FEM for a polycrystalline aggregate submitted to an elastic loading were compared with the CA predictions, grain by grain, for two different crystal structures (Fe and Ti). Considering the FEM as a reference tool, CA model predictions show an excellent propensity at predicting the local stress fields in polycrystals by capturing the neighborhood effect induced by grain orientations for a low computation time cost. The CA model has also shown its facility to evaluate quickly a grain influence on another grain stress level, and therefore, the orientations generating high stress concentrations in a grain can be easily identified. Using this capacity, the neighborhood effect has been shown to be able to at least double a grain stress level without the material showing any particular texture. [ABSTRACT FROM AUTHOR]

Quantum-dot cellular automata (QCA) nanotechnology is one of the proposed technologies for replacing CMOS technology. Shift registers are one of the important areas in the design of digital circuits and memory structures. Given the importance of shift registers, in this paper, new structures have been proposed for shift registers in QCA nanotechnology. At first, proposed D-latch is presented to be used in the main block of shift registers, which has only 18 cells, a delay of 0.5 cycles and less area than previous designs. Subsequently, a 4-bit series register will be presented using the proposed D-latch, which is at least 30% lower than the previous ones in terms of cell numbers and area. In addition, a reset pin is needed in shift registers which are used in microprocessors. Most of the previous designs did not have the reset pins and therefore a new version of 4-bit shift register which has the reset pin will be presented in this paper. New and former designs have been expanded from 2 bits to 8 bits, and parameters variations are presented in the table and diagrams. The proposed new designs have interesting features in terms of stability, number of cells and occupied area, compared to previous designs that do not have the reset capability. In addition, the proposed shift register is used to design an optimized LFSR circuit in QCA nanotechnology with only 157 cells and 0.2 µm2 area. [ABSTRACT FROM AUTHOR]

[Display omitted] • Frontal cellular automata reduce the computational time complexity. • The use of linked lists gives maximal acceleration in sequential calculations. • Frontal cellular automata preserve their advantages in parallel calculations. • FCAs are a very effective tool for the simulation of microstructure evolution. The paper focuses on analysing the computational time complexity of Frontal Cellular Automata (FCAs) and comparing it with Classic Cellular Automata (CCAs). Some variants of CCAs and FCAs are described and presented by showing differences in their structure and transition rules. Several variants of simple two-dimensional (2D) CAs and four variants of three-dimensional (3D) CAs for grain growth have been developed, tested and analysed. These four 3D CA algorithms are described. The calculation time of several simulation cases is measured for 2D and 3D CAs. The computational time complexity is determined on the basis of these measurements. The paper also takes into account the parallelisation of calculations with CAs. Time measurements show the possibility of accelerating the calculations. The paper also presents examples of the application of FCAs to solidification, recrystallisation, phase transformation and grain refinement with giving their simulation time. The computational complexity of different CAs is discussed, and FCAs with cells organised into linked lists show the lowest computational complexity. The paper ends with conclusions highlighting the low computational complexity and time efficiency of FCA. [ABSTRACT FROM AUTHOR]

A sequential dynamical system (SDS) consists of a graph G with vertices v 1 , … , v n , a state set A , a collection of “vertex functions” { f v i } i = 1 n , and a permutation π ∈ S n that specifies how to compose these functions to yield the SDS map [ G , { f v i } i = 1 n , π ] : A n → A n . In this paper, we study symmetric invertible SDS defined over the cycle graph C n using the set of states F 2 . These are, in other words, asynchronous elementary cellular automata (ECA) defined using ECA rules 150 and 105. Each of these SDS defines a group action on the set F 2 n of n -bit binary vectors. Because the SDS maps are products of involutions, this relates to generalized toggle groups , which Striker recently introduced. In this paper, we further generalize the notion of a generalized toggle group to that of a flexible toggle group ; the SDS maps we consider are examples of Coxeter elements of flexible toggle groups. Our main result is the complete classification of the dynamics of symmetric invertible SDS defined over cycle graphs using the set of states F 2 and the identity update order π = 123 ⋯ n . More precisely, if T denotes the SDS map of such an SDS, then we obtain an explicit formula for | Per r ( T ) | , the number of periodic points of T of period r , for every positive integer r . It turns out that if we fix r and vary n and T , then | Per r ( T ) | only takes at most three nonzero values. [ABSTRACT FROM AUTHOR]

In this paper, a mathematical model for simulating the grain evolution process of ceramic materials was constructed to investigate the effects of the sintering parameters on the microstructure in the spark plasma sintering process. Firstly, a new algorithm of removing the right angle of grain was improved and an improved cell state assignment method was proposed based on the cellular automata model. Then the sintering parameters were coupled into the model, and the simulation method of grain growth and pore evolution were proposed. Finally, a ceramic material grain evolution model with stomata structure for spark plasma sintering was constructed. The simulation results showed that the grain size increased exponentially with the increases of holding time and sintering temperature, while the pores gradually decreased with the increase of the two parameters and the density of the material. Besides, the uniformity of grain growth also decreased with the increase of holding time. These results conformed to the topological characteristics of grain growth and the law of grain boundary migration, and can provide support for the sintering parameters optimization of ceramic tool materials. [ABSTRACT FROM AUTHOR]

Quantum dot cellular automata (QCA) stands as a highly promising nanotechnology, capable of outperforming conventional CMOS technology. Leveraging its advantages, this paper addresses the challenges in adder circuits related to size, delay, and cost by integrating QCA technology. A novel layout for a co-planar full adder in QCA is introduced, featuring a half-adder design with 23 cells in a single layer without any crossover, achieving a delay of 0.25 clock cycles. By utilizing inter-cellular effects inherent in QCA technology, the presented designs offer significant improvements in a variety of design metrics, and a cost efficiency of 64.3%, distinguishing them from traditional logic design approaches. Additionally, in order to ensure an efficient routing channel and a consistent structure of the adder design, a Universal, Scalable, and Efficient (USE) clocking scheme has also been employed. The adder design is further used to build 4-bit and 8-bit Ripple Carry Adders. An extensive study on energy dissipation using QCADesigner-E and QCAPro tools is conducted for three tunneling energies (0.5 E k , 1 E k , and 1.5 E k). The full adder design showcases substantial improvement in energy to delay cost when compared to the closest reported design, achieving improvements of 91.66%, 89.03%, and 88% at 0.5 E k , 1 E k , and 1.5 E k , respectively. The results highlight enhanced circuit efficiency and streamlined layouts, outperforming existing models and offering substantial benefits to high-performance and energy-efficient computing systems. • To demonstrate simple and streamlined layouts, ensuring ease of implementation. • To designs consider the direction of signal flow, enhancing their efficiency. • To take the advantage of the inter-cellular effects' capability of QCA technology, leading to the observed advancements in the adder circuits. • Detailed energy dissipation calculations performed using QCADesigner-E and QCAPro. • Comprehensive Parameter Analysis: The analysis covers a wide range of important parameters, offering a holistic assessment of the adder designs. [ABSTRACT FROM AUTHOR]

[Display omitted] Modeling wildfire dynamics is complex and challenging due to the multiple scales involved in fire propagation, from physical–chemical processes to the interaction with topography and meteorological conditions. To provide reliable indicators of the risk of an ongoing wildfire, models aimed at informing policy-making should quantify the primary sources of uncertainty in their predictions. In this paper, we introduce a novel methodology built on top of Cellular Automata to assess the impact of uncertainty by implementing wildfire ensemble modeling using data from the Spanish National Forestry Data Repositories. Uncertainty is embedded in the model considering the ± 2 σ deviations from the medians of linear regressions of the canopy stratum with LiDAR metrics as explainable variables. The relevance of dynamic meteorological conditions in contrast to static environment conditions is analyzed. Our results suggest that an accurate account of the fuel model, including time-dependent wind and moisture maps, is mandatory to provide reliable predictions. Using a real case study (Concentaina's extreme wildfire), we also illustrate the importance of assessing the impact of the firefighters' mitigation efforts. [ABSTRACT FROM AUTHOR]

With the advent and advancement of connected and automated vehicle technologies, it is now possible to control connected and automated vehicles (CAVs) in mixed traffic flows to reduce traffic oscillations and enhance traffic flow performance. Recently, a control strategy for autonomous vehicles (AVs) named "The Follower Stopper controller" (FS) has been proposed. However, the existing studies for the FS strategy only considered the situation that all CAVs execute the FS strategy individually. And the impact on the mixed traffic flow when CAVs in the mixed traffic flow execute FS strategies as platoons is not investigated. To address this limitation, this paper proposes a control strategy for CAVs that considers the driving behavior of CAVs platoons based on the FS strategy, which allows CAVs to execute the FS strategy as a platoon. Then, a cellular automaton model of mixed traffic flow is developed based on the proposed strategy. Finally, a numerical simulation is conducted to analyze the impacts of the proposed strategy on traffic efficiency, traffic congestion, traffic oscillation, vehicle fuel consumption, and pollutant emissions under different penetration rates (PRs) of CAVs and traffic densities. Moreover, a comparative analysis with the FS strategy was conducted to verify the effectiveness and superiority of the proposed strategy. The result shows that (1) the proposed strategy can effectively mitigate traffic oscillations and reduce congestion. The improvement effect of the proposed control strategy on the mixed traffic flow is significantly affected by the penetration rate of CAVs as well as the traffic density. (2) Compared with the FS strategy, the proposed strategy has better performance in improving traffic efficiency, alleviating traffic oscillations, relieving congestion, and reducing fuel consumption and pollutant emissions under different traffic conditions. (3) The effectiveness of the FS strategy in improving the performance of mixed traffic flow is greatly limited by traffic density. There is a significant marginal utility of the FS strategy in improving traffic flow performance under high traffic density. However, the proposed strategy overcomes the limitations imposed by high traffic densities. The proposed strategy is highly adaptable to diverse traffic densities and can continuously enhance traffic flow performance as the penetration rate of CAVs rises. [ABSTRACT FROM AUTHOR]

A popular countermeasure against IP piracy is to obfuscate the Finite State Machine (FSM) which is assumed to be the heart of a digital system. Most of the existing FSM obfuscation strategies rely on additionally introduced set of obfuscation mode state-transitions to protect the original state-transitions of the FSM. Although these methods assume that it is difficult to extract the FSM behavior from the flattened gate-level netlist, some recent reverse engineering attacks could successfully break the defense of these schemes. The capability of differentiating obfuscation mode state-transitions from normal mode state-transitions makes these attacks powerful. As a countermeasure against these attacks, we propose a new strategy that offers a key-based obfuscation to each state-transition of the FSM. We use a special class of non-group additive cellular automata (CA), called D 1 ∗ CA , and it's counterpart D 1∗ CA dual to obfuscate each state-transition of the FSM. Each state-transition has its own customized key, which must be configured correctly in order to get correct state-transition behavior from the synthesized FSM. A second layer of protection to the state-transition logic enhances the security of the proposed scheme. An in-depth security analysis of the proposed easily testable key-controlled FSM synthesis scheme demonstrates its ability to thwart the majority of the state-of-the-art attacks, such as FSM reverse engineering, SAT, and circuit unrolling attacks. Thus, the proposed scheme can be used for IP protection of the digital designs. Experimentations on various IWLS′93 benchmark FSM designs show that the average area, power, and delay overheads our proposed multi-bit key-based obfuscated FSM design are 56.43%, 6.87%, and 23.41% while considering the FSMs as standalone circuits. However, experimentation on the Amber23 processor core shows these overheads drastically reduce (reported area, power, and delay overheads values are 0.0025%, 0.44%, and 0%, respectively) while compared with respect to the entire design. • The paper presents a Cellular Automata (CA) guided Finite State Machine obfuscation strategy using a special class of non-group CA, called D1 ∗ CA and its dual counterpart D1 ∗ CA dual. • Unlike the existing FSM obfuscation strategies, our technique does not rely on obfuscation mode state-transitions to obfuscate the FSM. Instead, we propose a key-based obfuscation to obfuscate each state-transition of the FSM. • We also offer a second layer of protection by logically encrypting the state-transition logic of the FSM. • Unlike the scan-based designs, our technique does not expose the internal state-elements to the attackers, thus offers better protection against scan-based side-channel attacks. • An in-depth security analysis shows the proposed method can prevent the state-of-the-art reverse engineering attacks, SAT, and circuit unrolling attacks. [ABSTRACT FROM AUTHOR]

• An efficient algorithm, i.e., eHCA-VRB, is proposed for crashworthiness. • The gradient information is not required for proposed algorithm during optimization process. • The constraints of the VRB rolling process are included in the updating rules for cell thickness. • The results show that the proposed eHCA-VRB is effective for nonlinear dynamic-response structural-optimization problems. Variable-thickness rolled blanks (VRBs) represent an important approach for constructing lightweight structures. However, the optimization of the crashworthiness and thickness distribution of VRB thin-walled structures under manufacturing constraints is a nonlinear dynamic-response structural-optimization problem that has a large number of design variables. To tackle this problem, this paper has extended and improved the hybrid cellular automaton for thin-walled structures (HCATWS) algorithm, and has proposed an extended hybrid cellular automaton for VRB thin-walled structures (eHCA-VRB) algorithm. This algorithm consists of an outer loop and an inner loop. The outer loop performs crash simulation analysis to define an appropriate target mass for the inner loop, whereas the inner loop adjusts cell thicknesses according to the internal energy density (IED) of the current cell and its neighboring cells so that the IED in the design domain becomes evenly distributed. A one-dimensional CA model is defined along with the rolling direction based on the thickness distribution of VRB thin-walled structures. Furthermore, the eHCA-VRB algorithm also generates a mapping relationship between the one-dimensional CA model and the FE model. To optimize the thickness distribution of VRB thin-walled structures under manufacturing constraints, our method uses cell thickness as a design variable and incorporates the constraints of the VRB rolling process in the cell thickness update rules. To verify the convergence and efficiency of the eHCA-VRB algorithm, VRB top-hat thin-walled structures are optimized for crashworthiness with/or without manufacturing constraints (M.C.), respectively. The results show that the eHCA-VRB algorithm can be used to efficiently solve the optimization problems of crashworthiness and the thickness distribution of VRB thin-walled structures under manufacturing constraints. [ABSTRACT FROM AUTHOR]

XOR-Majority graph (XMG) is a logic representation that is using exclusive-OR (XOR), majority-of-three (MAJ), and inverters as primitives, which is an extension of Majority-Inverter Graph (MIG). Previous work presented an axiomatic system, Ω, and its derived transformation rules for the manipulation of MIGs. By additionally introducing XOR primitive, to enable powerful logic rewriting in XMGs is inseparable from the development of the identities of MAJ-XOR operations. Further, since many emerging nanotechnologies, such as quantum-dot cellular automata (QCA) technology, are inherently majority-based, XMGs/MIGs are efficient logic representations to map into these nanotechnologies. In this paper, we first proposed two MAJ-XOR identities and exploited their potential optimization opportunities during structural rewriting. Then, we consider the inversion optimization in XMGs since the cost to implement inversion is prohibitive in some nanotechnologies. After that, we discuss the rewriting rules for multi-objective optimization. Finally, the experiments conducted over EPFL benchmark suites show that the proposed method can optimize the number of nodes, inverters, and levels of XMGs, which in turn benefits to the implementation cost of these circuits using QCA as well as quantum circuits. • We presented a multi-objective algebraic rewriting method for XOR-majority graphs (XMGs). • We exploited two MAJ-XOR identities that enable powerful logic rewriting. • The proposed methods are implemented in a publicly available logic synthesis tool. [ABSTRACT FROM AUTHOR]

• We establish the first mathematical model for portraying inner behaviors and computational procedures of mimic computing. • We propose a novel type of automata called mimic automata, i.e., the new model mentioned above. • The formal semantic and expressive ability of the new automata is obtained. • In an application scene, this new model is employed to address a problem on systematic structures of mimic computers. In this paper, we aim to establish a mathematical model for mimic computing. To this end, we present a novel automaton called a mimic automaton. First, a one-dimensional cellular automaton is used for expressing some dynamic changes in the structure of a computing unit, a sequential automaton is employed to describe some state transitions, a hierarchical automaton is employed to express the different granularities of some computing units, and a probabilistic automaton is used to depict some random changes of a computing unit. Second, a mimic automaton is obtained by combining the various types of automata mentioned above in a certain logical relationship. Compared with the existing models of mimic computing, the new model portrays the operational semantics for a mimic computing system, and it can directly describe the behaviors of a system. Furthermore, the new model possesses a stronger generality. [ABSTRACT FROM AUTHOR]

• Presenting the fault-tolerant majority gate using simple cells. • Verifying recommended gate by physical proof. • Presenting results in a recommended design for significant improvement in power consumption, area, and delay. • Developing an efficient one-bit QCA-based adder and 1:2 decoder based on a suggested gate. Quantum-dot cellular automata (QCA) has recently attracted significant notice thanks to their inherent ability to decrease energy dissipation and decreasing area, which is the primary need of digital circuits. However, the lack of resistance of QCA circuits under defects in previous works is a vital challenge affecting the stability of the circuit and output production. In addition, with the high defect rate in QCA, suggesting resistance and stable structures is critical. Furthermore, the 3-input majority gate is a fundamental component of QCA circuits; therefore, improving this essential gate would enable the development of fault-tolerant circuits. This paper recommends a 3-input majority gate which is 100% fault-tolerant against single-cell omission defects. Moreover, the fundamental gates are introduced based on the proposed gate. In addition, an adder and a 1:2 decoder are also designed. Using QCADesigner 2.0.3 and QCAPro software, simulations of structures and analysis of power consumption are performed. [Display omitted] [ABSTRACT FROM AUTHOR]

The combination model of cellular automata and multi-agent system were used in this paper for simulating spatio-temporal dynamics of urban expansion and its encroachment on other lands at the regional scale. The human system(contain authorities and residents) and their behavior, the landscape system and its behavior as well as the inter actions between them were all simulated in this paper. The behavior of human system is established based on multi-agent system, the authority agent and the resident agent were both regarded as abstract entities. The cellular automata is embedded into the model for simulating the spontaneous urban growth. The impact of neighbor cells were considered so that the expansion of urban lands can be limited near the existed urban lands. Moreover, the rural residential lands have higher probability to convert to urban lands if they were close to the cities or towns. Simulation of urban expansion is undertaken on the time series from 2000 to 2020 for Tianjin metropolitan region, the largest open coastal city in northern China. The results show that Tianjin’s urban lands focus on the epitaxial expansion around the central city accompanied with the growing exurb expansion distributing in multiple districts and counties. The croplands are taken the most area of the land-use types, 1764.03 km 2 are converted to urban lands, and more than one fourth of the rural residential lands are changed to urban lands in 2000–2020. The urban development and the cropland protection should be both taken into account to minimize the threats on food security and ecological environment. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract Grain structure is one of the most important factors that affect the mechanical properties of metallic alloys. Accurate prediction of as-cast grain structure is critical in the design and manufacturing of metal castings using an integrated computational materials engineering (ICME) approach. In this paper, a three-dimensional (3-D) model based on cellular automaton (CA) and process simulation was developed for predicting grain size of components produced by high pressure die casting (HPDC) of aluminum alloys. The concurrent nucleation and growth of grains were considered in the model. A test specimen casting, consisting of different wall thicknesses, was simulated using a finite element based casting process simulation software ProCAST®. The thermal history of the simulated casting was extracted and used in subsequent mesoscale CA modeling. Different thermal conditions were used to simulate grain nucleation and growth during HPDC. The grain morphology, grain density and grain size were obtained by CA modeling. Electron backscatter diffraction (EBSD) analysis was performed on aluminum castings of different wall thicknesses under various cooling rates to validate the simulation results. The 3-D grain structure model is in excellent agreement with the experimental results, and can be used in ICME design and development of aluminum castings. [ABSTRACT FROM AUTHOR]

Highlights • Impact of land use change on functional connectivity of multi-species was studied. • Key connecting nodes were prioritized according to their stepping-stone effects. • The population change based urban expansion is ideal to maintain connectivity. • Long dispersers may not have larger functional connectivity degree than short ones. Abstract As a primary concern in biodiversity conservation, understanding the impact of land use/cover change (LUCC) on functional connectivity has the overarching significance. Yet, LUCC simulation models used in previous studies are insufficient to tackle the complex and non-linear interactions of land-use components, and thus may not be able to provide the accurate impact assessments. This paper aimed to fill this gap and to find a solution that avoids significant connectivity loss in the future LUCC. The artificial neural network (ANN) based cellular automata (CA) and graph theory were combined, to explore potential changes in functional connectivity under alternative urban expansion scenarios. Results show that, both urban land and forested land will increase in all of future scenarios; however, functional connectivity of each species will still decrease except under a population change based scenario. The increase in forested land and the contrary connectivity loss proved the strong barrier effect caused by urban expansion. The impacts vary by species: small forest mammals might benefit more from the gain in the stepping-stone-like patches, while the intra-patch connectivity loss is the primary threat for large terrestrial mammals. Finally, we identified the key connecting patches (i.e., stepping-stones) and suggested that those patches should be prioritized for protection. [ABSTRACT FROM AUTHOR]

Abstract Quantum Cellular Automata (QCA) is one of the leading technologies in the electronics industry. Using this technology, low power consumption, small sizes, high density, and high-speed structures are achieved. Since flip-flops are one of the most important parts of digital circuits, designing a structure with a smaller size and delay and more facilities are of great importance. In this paper, novel edge-triggered D flip-flops with reset and set abilities are proposed in QCA technology using a suitable D-latch. The proposed works are optimized in terms of size and delay. Simulation results show that the proposed designs have a fewer number of cells and complexity, smaller area and less delay than similar circuits. The final proposed circuits have also set and reset abilities which rarely can be seen in previous designs. In addition, the proposed edge-triggered D flip-flops with set and reset abilities are designed in the coplanar method which facilitates the manufacturing process. [ABSTRACT FROM AUTHOR]

Highlights • A fast successive relaxation updating method for continuous-discontinuous cellular automaton(CDCA) is proposed. • A fast CDCA is developed, and increments of displacement and nodal force are enlarged by the accelerating factor. • A new discontinuity tracking method which combines cell space cutting and cell neighbor searching is proposed. • The optimal value of the accelerating factor is studied, and an adaptive iteration scheme is proposed. Abstract Because of its local property, cellular automaton method has been widely applied in different subjects, but the main problem is that the cellular updating is time-consuming. In order to improve its calculation efficiency, a fast successive relaxation updating method is proposed in this paper. Firstly, an accelerating factor ω is defined, and a fast successive relaxation updating theory and its corresponding convergence conditions are developed. In each updating step, the displacement increment is enlarged ω times as a new increment to replace the old one, similarly, the nodal forces for its neighbors caused by this displacement increment are also enlarged by the same accelerating factor, and do those updating operations until the convergence is achieved. By this method, the convergence rate is greatly improved, by a suitable accelerating factor, 90 to 98% of iteration steps are decreased compared to that of the traditional method. Besides, the influence factors for the accelerating factor are studied, and numerical studies show that the suitable accelerating factor is 1.85 < ω < 1.99, which is greatly influenced by cell stiffness, and the optimal accelerating factor is 1.96 < ω < 1.99. Finally, numerical examples are given to illustrate that the present method is effective and high convergence rate compared to the traditional method. [ABSTRACT FROM AUTHOR]

Highlights • A continuity-to-discontinuity enriched function technique is developed for elastodynamics. • Fast adaptive cellular automaton updating rules for the cell and its neighbors are developed. • A time domain cellular automaton theory for elastodynamics is proposed. • The cracks are independent of the integral meshes and no global matrix is needed. Abstract In this paper, the recently proposed continuous-discontinuous cellular automaton method (CDCA) is further developed for elastodynamic problems in 2D elastic solids. A continuity-to-discontinuity enriched function technique is developed for elastodynamics and combined with a cellular automaton formulation; the cellular automaton theory for elastodynamics, in which fast adaptive updating rules for the cell and its neighbors are developed, and the time domain CDCA are proposed. In this method, the cracks are independent of the integral meshes, and no assembled global matrix is needed for the whole process. Time-dependent equations for the cells are discretized by the Newmark method, and rapidly solved by the cellular automaton method. To analyze the fracture behaviors of elastic solids with dynamic loads, mixed-mode dynamic stress intensity factors are obtained by the interaction integral method. Some numerical examples for elastodynamic problems are studied to validate the accuracy and efficiency of the present method, and solutions from analytical method and some other methods are employed to show the high accuracy of the CDCA. [ABSTRACT FROM AUTHOR]

Grey wolf optimizer (GWO) is a newly developed metaheuristic inspired by hunting mechanism of grey wolves. The paramount challenge in GWO is that it is prone to stagnation in local optima. This paper proposes a cellular grey wolf optimizer with a topological structure (CGWO). The proposed CGWO has two characteristics. Firstly, each wolf has its own topological neighbors, and interactions among wolves are restricted to their neighbors, which favors exploitation of CGWO. Secondly, information diffusion mechanism by overlap among neighbors can allow to maintain the population diversity for longer, usually contributing to exploration. Empirical studies are conducted to compare the proposed algorithm with different metaheuristics such as success-history based adaptive differential evolution with linear population size reduction (LSHADE), teaching-learning based optimization algorithm (TLBO), effective butterfly optimizer with covariance matrix adapted retreat phase (EBOwithCMAR), novel dynamic harmony search (NDHS), bat-inspired algorithm (BA), comprehensive learning particle swarm optimizer (CLPSO), evolutionary algorithm based on decomposition (EAD), ring topology PSO (RPSO), crowding-based differential evolution (CDE), neighborhood based crowding differential evolution (NCDE), locally informed particle swarm (LIPS), some improved variants of GWO and GWO. Experimental results show that the proposed method performs better than the other algorithms on most benchmarks and engineering problems. [ABSTRACT FROM AUTHOR]

In South America, the presence of the non-native mollusc Limnoperna fortunei ( Dunker, 1857 ) (Mollusca, Bivalvia, Mytilidae) in rivers and reservoirs may result in several impacts on the environment and economic activities. In a continental scale, the factors that most influence the dispersion of the species are anthropogenic vectors such as the movement of boats and people. Due to this, distribution models based solely on climatic variables often fail to predict the areas most subject to invasion, both spatially and temporally. An alternative to overcome this problem is the evaluation assuming the phenomenon as a complex system. In this paper, we have used a cellular automata model to predict the spread of the golden mussel in the Brazilian territory, on a temporal and spatial scale. We assume three parameters of interest: a) altitude b) characteristics of the river, and c) human population density. Transition rules were defined based on various considerations discussed in the article. The algorithm estimated satisfactorily the risk of invasion by L. fortunei to date (year of 2016), and the simulations for the years 2030 and 2050 predicted a high risk of invasion in north and northeastern Brazil. The increased risk of invasion predicted by the model for the next decades indicates that prevention and control measures should be applied immediately and this is of the utmost importance for the country to be able to comply with the #9 Aichi target. [ABSTRACT FROM AUTHOR]

Segregation models often focus on private racial preference but overlook the institutional context. This paper represents an effort to move beyond the preference centricity. In this paper, an ideal Pigovian regulatory intervention is emulated and added into Schelling’s (1971) classic spatial proximity model of racial segregation, with an aim to preserve collective welfare against the negative externalities induced by the changing local racial compositions after individual relocations. A key discovery from a large number of cellular automata is that the Pigovian regulation tends to result in less segregated but also less efficient (in terms of aggregate utility) residential patterns than laissez faire . This finding, albeit from a highly stylized model, bears intellectual relations to an important practical question: What are the potential racial effects of Pigovian local planning interventions, such as financially motivated anti-density zoning or the collection of a development impact fee? On top of its modest policy implications, this paper demonstrates a bottom-up computational modelling approach to reconcile the preference-based and institution-orientated academic perspectives regarding racial residential segregation. [ABSTRACT FROM AUTHOR]

Monte Carlo and cellular automata simulations of grain boundary motion generally suffer from insufficient units of measure. This complicates the comparison of simulations with experiments, the consistent implementation of more than one driving force, and the development of models with predictive capabilities. This paper derives the proportionality constant relating the voxel interaction strength to a boundary energy, derives a formula for the boundary curvature, and uses the Turnbull expression to find the boundary velocity. Providing units of measure for the boundary energy and the boundary curvature allow Monte Carlo simulations and cellular automata simulations, respectively, to be subject to more than one driving force. Using the Turnbull expression to relate a driving pressure to a boundary velocity allows the remaining quantities in cellular automata simulations to be endowed with units of measure. The approach in this paper does not require any calibration of parametric links, but assumes that the voxel interaction strength is a Gaussian function of the distance. The proposed algorithm is implemented in a cellular automata simulation of curvature-driven grain growth. [ABSTRACT FROM AUTHOR]

This paper presents an investigation into the integration of cellular automata in the architectural design process, specifically in the design of high density residential building forms. Addressing the complexity of cellular automata rule definition, we explore the potential of visual and diagrammatic descriptions to address density, accessibility and natural light in the architectural context. This paper reflects on the theoretical framework of cellular automata (CA) and what characterizes their application to architectural design. The intention is to develop a tool to support the adaptation of architectural requirements into CA principles. Focusing on the application of CA at the beginning of the design process, we outline the implementation of CA generating three-dimensional architectural form for a high density residential project in the Netherlands. [ABSTRACT FROM AUTHOR]

The paper deals with recent developments about non-uniform cellular automata. After reviewing known results about structural stability we complete them by showing that also sensitivity to initial conditions is not structurally stable. The second part of the paper reports the complexity results about the main dynamical properties. Some proofs are shortened and clarified. The third part is completely new and starts the exploration of the fixed points set of non-uniform cellular automata. [ABSTRACT FROM AUTHOR]

Let t a and t b be a pair of relatively prime positive integers. We work on chains of n ( t a + t b ) agents which form together an upper and rightward directed path of the grid Z 2 from O = ( 0 , 0 ) to M = ( n t a , n t b ) . We are interested on evolution rules such that, at each time step, an agent is randomly chosen on the chain and is allowed to jump to another site of the grid preserving the connectivity of the chain and the endpoints. The rules must be local, i.e. , the decision of jumping or not only depends on the neighborhood of fixed size s of the randomly chosen agent, and not on the parameters t a , t b , n . Moreover, the parameter s only depends on t a + t b and not on n . In this paper, we design a rule such that, starting from any chain which does not cross the continuous line segment [ O , M ] , this rule reorganizes this chain into one of the best possible approximations of [ O , M ] . The stabilization is reached after O ( ( n ( t a + t b ) ) 4 ) iterations, in average. The work presented here is at the crossroad of many different domains such as modeling a stabilizing process in crystallography, stochastic cellular automata, organizing a line of robots in distributed algorithms (the robot chain problem) and Christoffel words in language theory. [ABSTRACT FROM AUTHOR]

The kinetics of microstructural evolution phenomena like recrystallization, grain growth, and phase transformation of deformed materials is affected by the characteristics of deformed microstructure. In fact, average grain size, grain morphology, texture and grain boundary properties of the deformed material determine the microstructure characteristics. In this paper, the reconstruction of deformed microstructure and changes in the microstructure in mesoscale are studied. Accordingly, the normal growth, topology deformation, and reconstruction of texture and grain boundary misorientation techniques are used to reconstruct the deformed microstructure. Therefore, probabilistic cellular automata method with hexagonal cells is used to create a microstructure with equiaxed grain morphology followed by a new modified topology deformation technique. In this technique, the quality and the quantity of the plastic deformation are considered by applying the deformation gradient tensor to the undeformed microstructure. Finally, a set of crystal orientations is created using a probabilistic algorithm relevant to the real texture of the material and then the crystal orientations are assigned to the deformed grains in such a way that satisfy the misorientation angle distribution. The accuracy of the numerical approaches is verified by comparing the experimental and the simulated results. [ABSTRACT FROM AUTHOR]

In this paper, we propose a parallel and reconfigurable hardware to generate harmonic music. The generated music is composed by melodic intervals determined from the combination of cellular automata in accordance to the standard protocol, which is called the Musical Instrument Digital Interface (MIDI) protocol. The hardware architecture is implemented in Field-Programmable Gate Array (FPGA), providing an alternative efficient yet autonomous tool for the study and research related to the field of random music. The architecture utilizes four types of cellular automata, depending on four neighborhood models in cellular automata. Thus, 16 possible combinations of cellular automata models are allowed. The applicability potential of the architecture is maximized as the configuration data, which influences the generated music final product, is done almost entirely by the user, with no virtual limit of the number of possible melodic combinations to be generated by the hardware. Thus, the portable engineered equipment can come handy in many real-world applications, such as neurology. In order to emphasize the usage versatility of the proposed design, the music composed thereby is provided in MIDI, and includes all notes and musical instruments known internationally. In order to validate the effectiveness as well as efficiency of the proposed design, we present several results regarding hardware design requirements in terms of area, operation frequency and power consumption as well as those regarding the generated melody's characteristics. The results are very promising. [ABSTRACT FROM AUTHOR]

In this paper, the overall corrosion damage process is modelled sequentially using cellular automata (CA) to describe the localised corrosion component, and finite element analysis (FEA) to account for the mechanical component resulting from the stress concentration effect of the corrosion defect (pit). Synchronous execution of the CA and FEA, and provision of feedback between both provides a good approximation of stress-assisted pit development. Qualitative and quantitative comparison of simulation results with experimental measurements show good agreement. In particular, the model shows that mechanical effects, notably plastic strain, accelerates the rate of development of localised corrosion. [ABSTRACT FROM AUTHOR]

The use of appropriate forming processes allows to obtain materials of required shapes, structures and properties. The technological conditions of the process can be optimized in view of the final microstructure. It can be achieved using different modeling methods, but recently use of cellular automata remains on the high level of interest. The aim of the study is a development and verification of the model of microstructure evolution during the flat rolling process. The microstructural model is based on frontal cellular automata, which uses for simulation of the rolling process of AISI 304L stainless steel. Modeling can be done on the basis of the general characteristics of the process i.e. the information about the duration of plastic deformation, time intervals between the passes, temperature and strain rate. The paper presents the modeling results of flat rolling process of AISI 304L stainless steel for different processing conditions. The modeling of three passes is presented. The results of the microstructure evolution can be observed as the microstructure maps at the selected time moments, as well as changes of average grain size, grain size distribution, fraction of recrystallization and flow stress. Some of the simulation results are verified with the experimental data. Model shows the high flexibility, allowing to take into account the various processing parameters. Simulation results are similar to the real processing conditions. It can be considered as a new tool for the development and optimization of flat rolling in view of final microstructure. [ABSTRACT FROM AUTHOR]

Quantum-dot Cellular Automata (QCA) is one of the emerging nanotechnologies, which yields attractive features like high speed, low power consumption and smaller size for implementing computing architecture in contrast to the CMOS technology. Numerous studies of adders and multiplier have been reported in this direction using QCA. This paper mainly focuses on designing of 8 × 8 Vedic multiplier in QCA using Urdhva Tiryagbhyam sutra. An efficient structure of 4-bit Vedic multiplier is used to construct an 8-bit multiplier. Moreover, the additions of generated partial products are realized using ripple carry adders and full adders. A generalized structure of N × N Vedic multiplier and the complexity of N × N multiplier design is also discussed. All the designs are simulated on QCADesigner tool and it confirms the efficiency of the proposed design. The simulation results show that the proposed design of 8 × 8 Vedic multiplier has reduced 60% cell count, 78% area, and 75% delay as compared to the 8 × 8 Wallace multiplier. In addition, it achieves equal complexity in term of cell count, but delay and area are reduced by 64% and 18% respectively compared to Array I multiplier. Furthermore, a general expression for the number of majority gates, inverters, crossovers, and delay is derived and compared with the Array I and Array II multiplier. [ABSTRACT FROM AUTHOR]

This paper presents a model to simulate built-up expansion and densification based on a combination of a non-ordered multinomial logistic regression (MLR) and cellular automata (CA). The probability for built-up development is assessed based on (i) a set of built-up development causative factors and (ii) the land-use of neighboring cells. The model considers four built-up classes: non built-up, low-density, medium-density and high-density built-up. Unlike the most commonly used built-up/urban models which simulate built-up expansion, our approach considers expansion and the potential for densification within already built-up areas when their present density allows it. The model is built, calibrated, and validated for Wallonia region (Belgium) using cadastral data. Three 100 × 100 m raster-based built-up maps for 1990, 2000, and 2010 are developed to define one calibration interval (1990–2000) and one validation interval (2000 − 2010). The causative factors are calibrated using MLR whereas the CA neighboring effects are calibrated based on a multi-objective genetic algorithm. The calibrated model is applied to simulate the built-up pattern in 2010. The simulated map in 2010 is used to evaluate the model's performance against the actual 2010 map by means of fuzzy set theory. According to the findings, land-use policy, slope, and distance to roads are the most important determinants of the expansion process. The densification process is mainly driven by zoning, slope, distance to different roads and richness index. The results also show that the densification generally occurs where there are dense neighbors whereas areas with lower densities retain their densities over time. [ABSTRACT FROM AUTHOR]

In this paper, from the mesoscopic point of view, under the assumption of metal corrosion damage evolution being a diffusive process, the cellular automata (CA) method was proposed to simulate numerically the uniform corrosion damage evolution of the outer steel tube of concrete filled steel tubular columns subjected to corrosive environment, and the effects of corrosive agent concentration, dissolution probability and elapsed etching time on the corrosion damage evolution were also investigated. It was shown that corrosion damage increases nonlinearly with increasing elapsed etching time, and the longer the etching time, the more serious the corrosion damage; different concentration of corrosive agents had different impacts on the corrosion damage degree of the outer steel tube, but the difference between the impacts was very small; the heavier the concentration, the more serious the influence. The greater the dissolution probability, the more serious the corrosion damage of the outer steel tube, but with the increase of dissolution probability, the difference between its impacts on the corrosion damage became smaller and smaller. To validate the present method, corrosion damage measurements for concrete filled square steel tubular columns (CFSSTCs) sealed at both their ends immersed fully in a simulating acid rain solution were conducted, and Faraday's law was used to predict their theoretical values. Meanwhile, the proposed CA mode was applied for the simulation of corrosion damage evolution of the CFSSTCs. It was shown by the comparisons of results from the three methods aforementioned that they were in good agreement, implying that the proposed method used for the simulation of corrosion damage evolution of concrete filled steel tubular columns is feasible and effective. It will open a new approach to study and evaluate further the corrosion damage, loading capacity and lifetime prediction of concrete filled steel tubular structures. [ABSTRACT FROM AUTHOR]

As the national center for politics and culture, Beijing’s urbanization level is very high. Many policies within the proposed Beijing–Tianjin–Hebei region coordinated development plan affect the expansion of urban land. Therefore, it is very important to predict urban land use changes in Beijing for planning and management purposes. In this paper, we integrated of MAS (multi-agent system) and CA (cellular automata) to simulate new satellite towns construction and ecological sensitivity impact on land use change. Physical and social driving factors were used in the combined model. The MAS involved the actions of three types of agent: regional authorities, property developers, and residents. The study used the CA model to simulate the neighborhood effects of urban land use, and the MAS model to simulate agents’ decisions. The new satellite towns and an ecological sensitivity analysis were embedded in the model to simulate the impact of decision making by the Beijing government on urban land expansion. Based on the land use data of 2005, the urban land area in 2010, 2015, 2020, and 2025 was predicted using the CA-MAS model. Urban expansion occurred faster during 2015–2025 than during the previous 10 years. Three land use types, i.e., cropland, woodland, and rural residential land, were the major sources of urban expansion. With respect to government decision making, the satellite towns were the priority areas of urban development, and urban development was restricted in ecologically sensitive areas. The New Districts of Urban Development were projected to become the main areas of future urban expansion in Beijing. The area designated for urban expansion around the ecologically sensitive areas was small. The results demonstrate that satellite towns and ecological sensitivity have large impacts on urban expansion. The results of this study will help to protect ecologically sensitive land, while enabling harmonious expansion of the city. [ABSTRACT FROM AUTHOR]

In this paper, we introduce the vulnerability and vulnerability index for systems described by cellular automata. A zone will be vulnerable to the space-time expansion of a given property during a time horizon if the property trajectory reaches the zone at a certain time. The space-time expansion of the property known as spreadability depends closely on the property definition, the cells properties and the transition function which governs the cellular automata evolution. These constraints exhibit two types of spreadability (inclusion sense and area sense) which affect vulnerable zones. When multiple zones are vulnerable during a given time horizon, we need criteria which describe whose are the most vulnerable. Then we consider iterative, average and global vulnerability index whose use depends on the considered phenomena. As an application we consider the flood phenomena. For this we use the two scale cellular automaton for flow dynamics modeling (2CAFDYM) over a given terrain. This application requires an adaptation of the general vulnerability index in order to take into account the both horizontal and vertical distributions of surface water. As practice application, we consider simulation for a basin in northern Morocco using a simulation software we have designed in Java Object Oriented Programming. Digital terrain model, geological maps and satellite image are used for input data. [ABSTRACT FROM AUTHOR]

Cellular automata (CA) models of spatial change have been developed and applied in the context of large regional or metropolitan areas and usually use regular cells, with spatial interactions and transition rules operating within fixed-size neighbourhoods. Model calibration has also been an area of intensive research with many models still using expert-based input to ensure visual calibration of modelled land use maps. In this paper, we present an innovative CA model where irregular cells and variable neighbourhoods are used to better represent space and spatial interaction. Calibration is based on an optimisation procedure that uses particle swarm (PS) to determine the optimal set of parameters of the CA model. Hypothetical test instances are used to assess the CA model and its calibration to small urban areas. Our conclusion was that the use of PS ensures calibration results for the CA model that compare very well with results obtained through other approaches reported in the literature. [ABSTRACT FROM AUTHOR]

Conceptual architectural design is a complex process that draws on past experience and creativity to generate new designs. The application of artificial intelligence to this process should not be oriented toward finding a solution in a defined search space since the design requirements are not yet well defined in the conceptual stage. Instead, this process should be considered as an exploration of the requirements, as well as of possible solutions to meet those requirements. This work offers a tour of major research projects that apply artificial intelligence solutions to architectural conceptual design. We examine several approaches, but most of the work focuses on the use of evolutionary computing to perform these tasks. We note a marked increase in the number of papers in recent years, especially since 2015. Most employ evolutionary computing techniques, including cellular automata. Most initial approaches were oriented toward finding innovative and creative forms, while the latest research focuses on optimizing architectural form. • State of the art with 75 papers of AI in Architectural Conceptual Design • Show several evolutionary systems that create innovative architectural designs. • The evolution of the research in terms of AI methods used • Trends in AI applied to conceptual design in architecture [ABSTRACT FROM AUTHOR]

The urban morphology is characterised by self-organisation where interactions of multiple agents produce emerging patterns on the urban form. Port-urban relationship added to the complexity of port cities' urban form. Most urban cellular automata (CA) models simulate land-use evolution through transition rules representing multi-factored local interactions. However, calibration of CA-based urban land use and transport interaction (LUTI) models often utilise manual methods due to complexity of the process. This limits insights on urban interactions to a few explored settlements and prevents applications for planning and assessment of transport policies in other contexts. This paper, therefore, addresses three main points. The paper (i) demonstrates an improved method for the calibration of CA-based LUTI models, (ii) contributes to a better understanding of the urban dynamics in port city systems by quantifying generalizable interactions from a wide range of port-urban settlements, and (iii) illustrates how the use of these interactions in a simulation model can allow long-term impact predictions of planning interventions. These were done by formulating a model in a similar structure as a neural network model to enable automatic calibration using an application of the gradient-descent algorithm. The model was then used to quantify the dynamics between land-use, geographic, and transport factors in 46 port-based and 10 non-port settlements across Great Britain, thus enabling cross-sectional analysis. Cluster analysis of the calibrated interactions in the study areas was conducted to examine the variations of these interactions. This produced two main groups. In the first group, consisting larger settlements, connections between ports and other urban activities were weaker than in the second group which consisted of smaller port-settlements. Overall, the findings of the research are consistent with existing evidence in the port-cities literature but go further in quantifying the interaction between urban agents within port-urban systems of various sizes and types. These quantified interactions will enable planners to better predict the longer-term consequences of their interventions. • This paper improved calibration process of urban model using optimization method from machine learning • The improved process allowed examination of wide range of port cities to counter the current trend of case-specific studies • Quantified interactions from wide range of port cities provide insights of the different land use behaviour in different types of port cities • Port-urban interactions in smaller urban areas with port are stronger thn in most other port cities • Interactions quantified in the study can be used in simulation to predict future port city urban form [ABSTRACT FROM AUTHOR]

In this paper, a subdomain hybrid cellular automata method is proposed to carry out the material optimization of thin-walled frame structure under transverse impact with minimum material cost, which is a typical optimal solution searching problem including many discrete variables. A nominal flow stress is introduced to convert the discrete design variables (cell materials) to be continuous for the update of cell materials. The global optimal searching ability of the proposed method is improved by the material update rule based on the step internal energy density target, which is adaptively defined during the material optimization to avoid the optimal solution jumping into a local one. PID control is employed to improve the robustness of the proposed method. The subdomain cellular automata model of a car body frame under transverse impact is constructed to separately perform the material and cost optimization by the proposed method and a parallel efficient global optimization method. The total material cost converges to CNY 1051 within 271 iterations using 32 CPUs by the parallel method and CNY 1101 within 8 iterations using 8 CPUs by the proposed method. The material optimization efficiency is significantly improved by the proposed method with good global searching ability. • New material optimization method of nonlinear dynamic problems with discrete variables. • Significant optimization efficiency improvement with the proposed method. • Global optimization improved by material update rule with step internal energy density. • No gradient required, so especially suitable for nonlinear problems with discrete variables. [ABSTRACT FROM AUTHOR]

[Display omitted] • We coupled a new mixed-cell CA approach and system dynamics model to forecast the ecosystem service value under three alternative scenarios. • The SD-MCCA model was demonstrated to have better performance, higher simulation accuracy and stronger robustness. • This paper employed the coefficient of sensitivity to determine the dependence of ESV on the land use variations. Land use is a crucial factor affecting ecosystem service value (ESV), and forecasting future land use changes and ESV response can guide urban planning and sustainable development decisions. However, the traditional Cellular Automata (CA) model supposes that each cell has only one land use type at each time step, neglects the mixed structure and proportional distribution of land use units, does not take into account its quantitative continuous dynamic change, and lacks the exploration of land use quantity structure and spatial pattern optimization. This study employed a novel mixed-cell cellular automata (MCCA) approach, coupled with the system dynamics (SD) model to predict the spatiotemporal pattern of land use under the natural increase scenario (NIS), economic development scenario (EDS) and ecological protection scenario (EPS) in Xi'an, China, in 2030. The equivalent coefficient method was utilized to investigate the heterogeneity distribution and sensitivity of ESV. The results demonstrated that SD-MCCA exhibited remarkable prediction accuracy and robustness. The main changes in land use in 2000–2015 were due to urban expansion, the conversion of arable land into construction land, and the conversion between grassland and arable land. The total ESV increased from 19554.36×106 CNY in 2000 to 19618.39×106 CNY under the EPS in 2030, and the contribution of climate regulation and hydrological regulation to ESV was the highest. Spatial heterogeneity of ESV revealed a certain regularity, and the high value region was chiefly concentrated in woodland and grassland with favorable ecological conditions. Land use variations under NIS and EPS improved ESV, while the ESV had a negative response to land use transformations under the EDS. This research provides a new way to identify the relationship between future land utilization scenarios and ESV, which is of great significance for the management of land resources and formulation of ecological compensation standards. [ABSTRACT FROM AUTHOR]

Abstract: In this paper we provide an overview of the possible -limit set structures for 104 of the 256 asynchronous elementary cellular automata over the circle graph on vertices. We consider only fixed, sequential updates where the update sequence is given by a permutation of the vertices, that is, the class of sequential dynamical systems. The ECA rules covered are precisely the -invariant rules, that is, the rules for which the set of periodic points does not depend on the permutation update sequence. This paper reviews existing work on -invariance and cycle-equivalence, and provides and atlas of the possible limit set structures up to topological conjugation. [Copyright &y& Elsevier]

Abstract: This paper investigates a variant of cellular automata, namely -CA. Indeed, -CA are cellular automata which can have different local rules at each site of their lattice. The assignment of local rules to sites of the lattice completely characterizes -CA. In this paper, sets of assignments sharing some interesting properties are associated with languages of bi-infinite words. The complexity classes of these languages are investigated providing an initial rough classification of -CA. [Copyright &y& Elsevier]

Abstract: In this paper, a model based on Cellular Automata (CAs) for predicting wildfire spreading is presented. The proposed model is inspired by existing fire spread models, but also includes a number of changes and additions, compared to them. Primary goal of the paper is to design and implement a software-based model as well as a corresponding hardware-based one that will sufficiently describe real fires, but will also have less stringent requirements on computational resources and computational power for execution. Therefore, an effort has been made to minimize the complexity of the model and the resulting computational burden aiming at an implementation that will have a practical significance in predicting the evolution of a fire. The proposed model is implemented on an Altera®Stratix IV®FPGA (Field-Programmable Gate Array), designed to execute in a parallel way in order to produce valuable information in real time that can be used to optimize response to a fire crisis. The FPGA design results from the automatically produced synthesizable VHDL code of the CA model and is advantageous in terms of low-cost, high speed and portability. The resulting implementation sufficiently depicts the natural phenomenon of wildfire spreading and provides short calculation times. Finally, the presented FPGA implementation of the proposed CA model offers the possibility a portable system to be designed, connected with GPS as well as GIS and/or wind monitoring systems able to provide real-time information concerning the wildfire propagation on the under test area. [Copyright &y& Elsevier]

Abstract: Objective: This paper presents a conceptual model that is developed upon a characterization of human papillomavirus type 16 (HPV16) which is used to build a simulation prototype of the HPV16 growth process. Methodology: The human papillomavirus type 16 is the principal virus detected in invasive lesions of cervical cancer, and associated with the greater persistence and prevalence in pre-malignant and malignant lesions. The probability of acquiring an infection with HPV16 is extremely high in sexually active individuals. However, an HPV16 infection can disappear after becoming a histological confirmed case. According to the characterization of HPV16 proposed in this paper, cells as compared to a society behaves as a complex system, i.e., cells behave in a cooperative manner, following a set of rules defined by local interactions among them. Such complex system is defined by combining a cellular automaton and agent-based models. In this way, the behavior of the HPV16 is simulated by allowing the cellular automaton to follow such parameterized behavior rules. Results: Both cross-sectional and prospective studies indicate that HPV16 infection persistence increase the risk of high-grade CIN, as observed in the results provided by the growth simulation model of HPV16. The average growth rate extrapolated over 52 weeks (12 months) and calculated by the model showed a 37.87% growth for CIN1, 35.53% for CIN2 and 16.92% for CIN3. Remarkably, these results are similar to the results obtained and reported by clinical studies. For example, the results obtained using the proposed model for CIN2 and the results obtained by Östör [36], have a differential of 0.53 percentage points while have a differential of 2.23 percentage points with the results obtained by Insinga et al. [51]. Also, for the CIN3, the results obtained using the proposed model, have a differential of 2.92 percentage points with the Insinga et al. [52], results. Conclusion: Through the specification of parameterized behavior rules for HPV16 that are simulated under the combined technique of cellular automata and agent-based models, the HPV life cycle can be simulated allowing for observations at different stages. The proposed model then can be used as a support tool in the investigation of HPV16, in particular (as part of our future work) to develop drugs as agents in the control of the HPV16 disease. [Copyright &y& Elsevier]