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Abstract: A left canonical factorization theorem for rational matrix functions relative to the unit circle is presented. The result is a time invariant version of a recent strict LU factorization theorem for certain semi-separable operators, due to Dewilde (2012) [6]. Explicit formulas for the factors are also given. The theorem is proved, first by using the state space method of Dewilde (2012) [6], and next by using an operator theory approach. In both cases the main part of the proof concerns rational matrix functions that are unitary on the unit circle. [Copyright &y& Elsevier]

The integration of multiterminal hybrid HVDC grids connecting LCC- and VSC-based networks faces several technical challenges such as DC fault isolation, ensuring multi-vendor interoperability, managing high DC voltage levels, and facilitating high-speed power reversal without interruptions. The two-stage DC-DC converter emerges as a key solution to address these challenges. By implementing the modular multilevel converter (MMC) structure, the converter's basic topology includes half-bridge sub-modules on the VSC side and full-bridge sub-modules on the LCC side. However, while this topology has been discussed in the literature, its connection to an LCC-based network with controlled current magnitude lacks detailed analysis regarding operational challenges, control strategies under various scenarios, and design considerations. This paper fills this gap by providing comprehensive mathematical analysis, design insights, and control strategies for the modular DC-DC converter to regulate DC voltage on the LCC-HVDC side. Additionally, the proposed control scheme minimizes the interfacing inductor between the two bridges, ensuring uninterrupted power flow during reversal and effective handling of DC faults. Validation through Control-Hardware-in-the-Loop testing across diverse operational and fault scenarios, along with a comparative analysis of different converters, further strengthens the findings. © 2017 Elsevier Inc. All rights reserved. [ABSTRACT FROM AUTHOR]

The rapid growth in HVDC grids is becoming inevitable for long-distance power transmission. Therefore, the idea of interconnection between the point-to-point links becomes essential. However, these point-to-point connections face several challenges such as the requirement of DC fault blocking capability, interfacing of different grounding schemes, offering multi-vendor interoperability, and difficulty to achieve high DC voltage stepping. DC-DC converters are considered the optimum solution to tackle these challenges in DC grids interconnection. In this paper, a new hybrid modular DC-DC converter is proposed that achieves a low number of semiconductors, low losses, and cost in comparison to other DC-DC converters due to the utilization of thyristors. The new DC-DC converter consists of two hybrid MMC bridges connected through an isolating transformer. Each MMC bridge is comprised of half bridge submodules and bidirectional thyristors. Detailed mathematical analysis, design, and control are illustrated. A comparison is carried out between different topologies in terms of semiconductor count, power loss, and cost. Also, both simulation model and experimental test rig are built to validate the proposed hybrid modular DC-DC converter under different scenarios. Finally, another variant of the hybrid-thyristor based converter (version two) is proposed for multiport DC-Hub application to achieve DC fault blocking without turning off all connected bridges. [ABSTRACT FROM AUTHOR]

Investigating the effects of periodic magnetic field and triple diffusion on bioconvection flow through a rotating cone populated by oxytactic bacteria and an Eyring-Powell fluid is innovative and significant. The magneto-bioconvection flow of an Eyring-Powell multi-diffusive fluid across a spinning cone is investigated in this paper, considering the effect of oxytactic microorganisms. The non-similar technique is used in the mathematical analysis of the flow over a spinning cone. The flow under consideration contains two diffusive species: liquid hydrogen and liquid oxygen. In light of the periodic magnetic field, the surface gradients, notably skin friction, exhibit wavy effects in the boundary layer domain. The governing equations for the fluid flow in the current flow problem, accompanied by heat diffusion, species diffusion, rotation, bioconvection, and periodic magnetic, are highly coupled nonlinear PDEs dependent on the proper initial and boundary conditions. Mangler's transformations convert them into non-dimensional forms, and numerical non-similar solutions are produced using implicit finite difference approximation and quasi-linearisation. The enriching values of bioconvective Rayleigh number Rb decline the velocity F, as a result, lessen the friction between the surrounding fluid and the cone's surface. The improving Peclet number Pe and microbial density difference σ reduced the microorganism density profile and heightened the microorganism density number R e - 1 / 2 N n. [ABSTRACT FROM AUTHOR]

In this manuscript, we are going to study a novel model of the dynamics of alcohol consumption under induced complications. The mentioned model is considered under the concept of conformable fractional order derivative (CFOD). Currently, most of real-world problems are considered under fractional order derivatives because of their stable and global behavior. First, we will investigate the model for qualitative theory including existence and uniqueness of solution and Ulam-Hyers stability. For qualitative theory, we will use fixed point theory. In addition, we use a numerical method to find the approximate solution of the proposed model. In the final part of the paper, we give a detailed discussion of its numerical results and its graphical presentation. [ABSTRACT FROM AUTHOR]

In this paper, the consensus tracking problem for the linear and nonlinear partial difference multi-agent systems with switching communication topology and control delay is investigated. Based on relative local measurements of neighboring followers, while considering spatio-temporal discretization and initial state deviation, a discrete distributed consensus protocol with initial value learning is designed for each agent via D-type iterative learning approach. Through rigorous mathematical theoretical analysis, the necessary and sufficient conditions are obtained. Under the switching of the communication topology, these conditions ensure that the consensus tracking control of the MASs can be solved. After applying the designed protocol, in the sense of the L 2 norm and along the positive direction of the iteration axis, the consensus tracking error between any two agents can converge to zero. Finally, some simulation examples are used to demonstrate the validity of the protocol and theoretical results. • A novel partial difference MASs dynamic model is established to describe the discrete spatio-temporal evolution behavior. • A new distributed iterative learning approach with initial value learning for partial difference MASs is given. • The proposed control approach can solve the problem of switching topology and control delay simultaneously. [ABSTRACT FROM AUTHOR]

In this paper, a fractional-order Hantavirus infection model incorporating harvesting is formulated and investigated. The populations are divided into susceptible mice, infected mice and alien species. Mathematical analysis and numerical simulations are performed to clarify the characteristics of the proposed fractional-order Hantavirus infection model. The existence, uniqueness, non-negativity and boundedness of the solutions are examined. The local stability of the equilibrium points of the fractional-order model is studied. The mathematical proof of the existence of transcritical bifurcation is given by using Sotomayor's theorem. The theoretical findings are illustrated by numerical simulations. The impact of fractional-order, competitive effect of alien species on mice, competitive effect of mice on alien species, carrying capacity and harvesting efforts on the stability of the Hantavirus infection model are studied. The basin of attraction regions is also illustrated. [ABSTRACT FROM AUTHOR]

With an increase in the number of internet users and the need to secure internet traffic, the IPv4 protocol has been replaced by a more secure protocol, namely IPv6. The IPv6 protocol does not allow intermediate routers to fragment the on-going packets. Moreover, due to IP tunneling, some extra headers are added to the IPv6 packet, exceeding the packet size, resulting in increased packet drops due to lower path mtu. One probable solution is to use Path MTU Discovery (PMTUD) to know the path mtu using ICMP packets. Due to dependency on ICMP error messages, this method faces security and failure issues. In this paper, we propose a Dynamic MTU (DMTU) scheme, which tries to handle the packet drops in IPv6 network, by dynamically adjusting the MTU of each link depending upon the incoming packet size, thereby reducing the number of packet drops by a significant amount. Unlike PMTUD, the algorithm works on intermediate node level which is further optimised by assigning specific phases for validation and then, for processing. The method has ability to work in standalone and in parallel with PMTUD. Using mathematical and graphical analysis, our scheme proves to be much more efficient than the state-of-the-art PMTUD scheme. [ABSTRACT FROM AUTHOR]

This paper studies the underwater glider trajectory tracking in currents field. The objective is to ensure that trajectories fit to the straight target track. The underwater glider model is introduced to demonstrate the vehicle dynamic properties. Considering currents disturbance as well as the uncertain status of the glider controlled by complicated roll policies, the trajectory tracking task can be classified into the model-free optimization. Such problem is difficult to solve with mathematical analysis. This work transfers the underwater glider trajectory tracking into a Markov Decision Process by specifying the actions and observations as well as rewards. On this basis, a neural network controls framework called experience breeding actor-critic is proposed to handle the trajectory tracking. The EBAC enhances the explorations to the potentially high reward area. And it steers glider heading meticulously so as to counteract the currents influence. Through simulation results, the EBAC shows a desired performance in controlling the gliders to accurately fit the target track • The underwater glider simulator is established to develop algorithms and evaluate the effectiveness. • The novel experience breeding actor-critic algorithm is applied for underwater gliders trajectory tracking. • The optimizing framework of glider trajectory tracking from the Markov decision process perspective is proposed. • The proposed method enhance the tracking accuracy compared with PID and SMC with the LOS guidance. [ABSTRACT FROM AUTHOR]

• Fractional calculus is a fast growing field in mathematics, science and engineering. • This is a bibliographic analysis of 351 articles that use Atangana-Baleanu operators • Articles grow by 80.25% yearly from all countries, especially developing countries. • This shows the influence of this rapidly growing field of applied mathematics. Fractional calculus is a branch of mathematical analysis that studies the several different possibilities of defining real number powers or complex number powers of the differentiation and integration operators. Recently, Atangana and Baleanu proposed operators based on generalized Mittag-Leffler functions to solve fractional integrals and derivatives. These contributions have set off an explosion of new research in fractional calculus, and this paper present a comprehensive bibliometric analysis of the peer-reviewed papers inspired by Atangana and Baleanu. In total, 351 papers in the Scopus database have used Atangana-Baleanu operators and this number is growing at 80.25% each year since 2016. These papers were written by 343 authors, predominantly from Mexico, Saudi Arabia and India. Although these data show that Atangana-Baleanu operators support global and fast growing scientific research, the field is dominated statistically by a few productive individuals. I present citation network of the most prolific authors and show collaboration and citation networks. Finally, I present a thematic analysis of the papers applying Atanagana-Baleanu operators and show how research forms clusters based on: analytical solutions, numerical simulations or applications in science and engineering. [ABSTRACT FROM AUTHOR]

The aim of this study is to develop new and efficient theories for handling complex and unreliable data in real-world scenarios. The proposed approach integrates two distinct theories: the Bipolar Complex Fuzzy Set (BCFS) and the Soft Set (SS), resulting in a novel and superior method compared to existing solutions. Furthermore, the value of big data analytics cannot be overstated as it provides businesses with the opportunity to use their data to find areas for development and progress. To gain insights from raw data, it must first be collected and organized. Data modeling represents these large, complex data sets in a visual format, such as a chart or diagram. However, the visualization process often results in uncertainties and inaccuracies, highlighting the need for a more robust approach to data analysis. To address this issue, this paper introduces the concept of Bipolar Complex Fuzzy Soft Relations (BCFSRs), a fuzzy decision-making method within a complex bipolar fuzzy environment that can have the advantages of both a Bipolar Complex fuzzy relation and a soft relation at the same time. In BCFSRs, an element can have degrees of membership in both the positive and negative directions, reflecting a more nuanced and versatile representation of uncertainty or ambiguity. These mathematical ideas are explained through the Cartesian product of two Bipolar Complex Fuzzy Soft Sets (BCFSSs) and serve to simplify the decision-making process by presenting the BCFSSs in a clear and concise manner. The inventive notion of the BCFSRs elucidates the combined positive and negative effects of anything with parameterization. To support organizations in making data-driven choices and obtain insights for strategic planning and inventiveness, the analysis of big data is essential in several industries, including financial services, marketing, and medical treatment, among others. To choose the optimal big data analytics for efficient operation, this research presents modeling methodologies based on BCFSRs, including the formulation and analysis of scoring functions. The validity of the proposed work is demonstrated through a comparison study with existing methods, providing valuable insights for effective data analysis. • Bipolar Complex fuzzy and soft sets are presented. • Introduced novel, and effective ideas to manage complex, unreliable data. • Presents modeling methodologies based on Bipolar Complex fuzzy soft information. • Conducted a comparative study of existing techniques. [ABSTRACT FROM AUTHOR]

With the recent focus marked on energy efficiency and solar energy development, much research is being dedicated to the development of enhanced maximum power point tracking (MPPT) algorithms for photovoltaic applications. However, the main criteria with regard to tracking performances and circuit implementation are still considered as a major challenge under rapid varying weather conditions. In this paper, a T-S Fuzzy–integral backstepping-based hybrid MPPT technique is proposed for rapid, accurate and efficient tracking. The proposed technique enables reliable and stable operation under fast dynamic environmental changes. Besides, it is simple as it does not require extra atmospheric sensors. The theoretical analysis addressed in this study is verified through simulations via Matlab/Simulink and experimental outdoor tests. A comparison with different other MPPT techniques is provided to highlight the performances of the developed MPPT method. • An MPPT controller based on TS Fuzzy and integral backstepping control is proposed. • A detailed mathematical analysis has been presented. • The suggested MPPT technique has been compared to P&O, MIC, PSO and P&O-FOPI. • The proposed controller is validated through simulations and experimental tests. [ABSTRACT FROM AUTHOR]

Abstract This paper presents three different necessary and sufficient conditions for the admissibility and robust stabilization of singular fractional order systems (FOS) with the fractional order α : 0 < α < 1 case. Two results are obtained in terms of strict linear matrix inequalities (LMIs) without equality constraint. The system uncertainties considered are norm bounded instead of interval uncertainties. The equivalence between quadratic admissibility and general quadric stability for FOS are derived. A condition is not only strict LMI condition without quality constraint but also avoid a singularity trouble caused by the superfluous solved variable. When α = 1 and E = I , the three results reduce to the conditions of stability and robust stabilization of normal integer order systems. Numerical examples are given to verify the effectiveness of the criteria. With the approaches proposed in this technical note, we can analyze and design singular fractional order systems with similar way to the normal integer order systems. Highlights • This paper presents three necessary and sufficient conditions for the admissibility and robust stabilization of singular FOS. • Two results are obtained in terms of strict LMIs. The system uncertainties considered are norm bounded uncertainties. • The strict LMI approaches have been developed to both judge admissibility and design robust stabilizing controller. • The electrical circuit on Fig. 1 with R , capacitances are the α order derivative i C (t) = C d α u C (t) dt α which is clear real-world example in fact. • It is worth noting that the criteria obtained in this technical note can be regarded as a natural extension of Lyapunov stability. [ABSTRACT FROM AUTHOR]

Abstract The article describes the method of relative estimation of tasks which is used in Agile methodologies. The presented method is designed to reduce estimating time and requirements to developers. The article describes algorithms that provide the high accuracy to estimation of large projects with a relatively considerable number of tasks. The methodology advantages are in an error calculation of estimation and mathematical findings of the reference task which is necessary to tasks estimation. The algorithms can be automated which lowers time costs and requirements to the level of developers. These advantages are very important to implementation of the best Agile practices. This paper is intended for IT-project managers, analysts and practitioners involved in large digital projects, software developments, project management in the sphere of knowledge intensive projects implementation and execution. The approach described in this paper enables to review additional advantages for optimisation of time, cost and resource parameters of the projects especially in the up-to-date environment conditions taking into consideration rapid software development. The method proposed in the paper is based on the features of human perception of the tasks complexity. [ABSTRACT FROM AUTHOR]

Graphical abstract The graphical structure of a simple closed-loop supply chain network utilizing in this paper. Highlights • Introducing a new multi-objective stochastic closed-loop supply chain network design with social considerations. • Presenting a number of new hybrid metaheuristic algorithms to create a better interaction between the search phases. • Comparison of developed approaches by a set of efficient evaluation metrics of Pareto optimal sets. • Confirming the performance of proposed RDKAGA in practice. Abstract Nowadays, operation managers usually need efficient supply chain networks including important design factors such as economic and social considerations. The recent decade has seen a rapid development of controlling the uncertainty in supply chain configurations along with proposing novel solution approaches. By investigating the related studies, this paper shows that most of the current studies consider the economic aspects and just a few works present the two-stage stochastic programming as well as social considerations to design a closed-loop supply chain network. This motivated our attempts to consider economic and social aspects simultaneously by using the mentioned suppositions among the first studies. Another main contribution of this paper is the hybridization and tuning of a number of recent algorithms to address the problem. The results show that the proposed hybrid metaheuristic algorithms outperform the best existing techniques on the majority of case studies. [ABSTRACT FROM AUTHOR]

Tumor growth models have proved as an important tool to produce an engineering background for cancer therapy either by designing therapeutic procedures combined with control engineering or by using the models for simulations and evaluation of treatment procedures. Mathematical modeling has been critical for the description of tumor growth, which is a highly complex process, as a finely chiseled tumor growth model always outlines the measurements and the physiological processes of the tumors. Therefore, a mathematical model involving partial differential equations for the growth of tumor have been studied, modified and developed in this paper. It is based on the deterministic model of an avascular tumor growth which is framed in a system of nonlinear coupled PDEs, describing the proliferating, quiescent, necrotic, and surrounding cells densities, accompanied by a supply of the nutrients. These equations are explained numerically by the Finite Difference Method. Furthermore, the simulations are carried out by introducing the Gompertz growth rate function for mitosis rate function g(c) of proliferating cells in the model. The discretization forms a system of coupled nonlinear difference equations which are solved at each iteration. The algorithm is implemented sequentially in MATLAB 2018a and numerical results suggest that the employed model is an authentic tool for analyzing the dynamics of tumor. [ABSTRACT FROM AUTHOR]

In this paper, we present a numerical scheme and mathematical analysis for the famous three-dimensional quadratic autonomous self-govern system that happens to be chaotic with the coexistence of multi-scroll attractors. The scheme is based on the Atangana-Baleanu fractional derivative in the Caputo sense. The formulation of these schemes introduces the non-local and non-singular kernel to the fractional derivatives. The fractional derivative is then approximated using the family of the Adams–Bashforth schemes. The results are presented in both numerical and graphical as the fractional order β varies between 0 < β ⩽ 1. We study the proposed model in the both generalized case that is 0 < β < 1 and the case where β = 1 , which is the integer standard case. Due to the impact of the generalized case, the proposed model is able to maintain the coexistence of multi-scroll attractors. [ABSTRACT FROM AUTHOR]

This paper contributes an adaptive temporal-causal model describing how the direction of evolutionary processes can be driven by the (free) behavioral choices made by the individuals. The model was designed based on the role of behavioral plasticity as described in the literature. Simulations indeed illustrate the overall process that takes place, and verification by mathematical analysis has been performed which shows that the model does what is expected. [ABSTRACT FROM AUTHOR]

This paper explores how becoming a conspiracy thinker can be modeled by an adaptive mental network model based on theories from the empirical literature. A number of simulation scenarios for different types of persons illustrate its usefulness. The model has been verified by mathematical analysis of stationary points and equilibrium values, and validated against data points representing patterns expected from the empirical literature. [ABSTRACT FROM AUTHOR]

A conducting disc above two series connected concentric coils carrying current in the opposite direction gets levitated by magnetic repulsion principle. The disc achieves stable floating position when the electromagnetic force developed on the disc is equal and opposite to the gravitational weight of the disc. However, when there is an external disturbance, the disc will throw off from the center laterally, due to the repulsive force, based on the direction of the disturbance. Several techniques exist in literature to determine the force on the disc coaxial with the coils based on Finite Element Methods (FEM). In this paper, an approach to solve the integrodifferential equations using Finite Difference Method (FDM) has proposed to calculate the lateral force on the disc when it moves away from the axis of the disc. By using the FDM, we can discretize the disc into several curvilinear elements, and a mathematical formulation has developed. The maximum lateral stable region that the disc can remain in its stable floating position has determined by using this lateral force. A mathematical program has developed in MATLAB to calculate the force on the disc. Also, a model has designed in COMSOL Multiphysics, to compare the results obtained. [ABSTRACT FROM AUTHOR]

In this paper, we introduce a novel model that simulates the spread of the monkeypox virus. The new model takes into account the effect of the interaction between the human and rodent population along with some realistic factors that have not been introduced before such as imperfect vaccination and nonlinear incidence rates. Moreover, the human population is further divided into low-risk and high-risk groups to better reflect recent observations. To understand the dynamics of the new model, the existence, uniqueness, and continuous dependence on initial conditions, as well as its positivity and boundedness of the model are investigated in detail. The obtained solution is proved to be positive and has bounded behavior. Furthermore, the reproduction number R 0 for the proposed system is computed and detailed bifurcation analysis is performed to reveal major qualitative changes in the model's dynamics. In addition, we investigate the influence of key parameters on the basic reproduction number. We also explore and analyze the stability of equilibrium points in the space of parameters. The new findings reveal that the virus is more frequently witnessed among the high-risk group, which may provide some restrictions to stop the spread through social limitations. To validate our theoretical results, we conduct numerical simulations, which provide insights into the behavior of the model under different conditions. The new findings aim in developing preventive control measures to suppress the spread of the virus and to develop effective strategies for controlling and preventing outbreaks, ultimately protecting public health and minimizing the impact of the disease. [ABSTRACT FROM AUTHOR]

In this paper, a new interference-tolerant fast convergence zeroing neural network (ITFCZNN) using a novel activation function (NAF) for solving dynamic matrix inversion (DMI) is presented and investigated. Compared with the original zeroing neural network (OZNN) models, the proposed ITFCZNN not only has the ability to converge to 0 within a fixed-time, but also resist different types of interference and noises in solving DMI problems. Besides, detailed mathematical analysis of convergence and robustness of the ITFCZNN are provided. Comparative numerical simulation verifications of the new ITFCZNN and the OZNN activated by other commonly used activation functions (AF) are also provided to demonstrate the better robustness, effectiveness and fixed-time convergence of the ITFCZNN. In addition, a mobile manipulator path tracking application example is given to verify the applicability and feasibility of the ITFCZNN with interference and noises. Both of the theoretical analysis and numerical simulation results verify the effectiveness and robustness of the ITFCZNN model. [ABSTRACT FROM AUTHOR]

It was demonstrated recently that ideal capacitors can not exist physically and that the behavior of real-world inductors and capacitors is characterized by fractional-order (FO) models. Therefore, the modeling and analysis of FO electrical circuit networks (FO-ECN) has gained considerable interest. This paper introduces the basic principles of a class of rectangular prism n -units (♢ × n) RLC FO-ECN, including the mathematical modeling and the analysis of the impedance magnitude and phase. Three general formulas of the equivalent impedance between two nodes of the FO-ECN are obtained by the matrix transform method. The relationship between the impedance and the FO-ECN parameters, including the capacitance, inductance, number of circuit units and FO are investigated. Numerical simulations reveal dynamical phenomena not exhibited by ordinary ECN. [ABSTRACT FROM AUTHOR]

The aim of this paper is to investigate stability of an isothermal glass tube drawing process through control parameters by the method of linear stability analysis. We want to see how the process parameters effect stability of the physical system being considered. For this purpose, we not only prove the existence and uniqueness of the solutions of steady state isothermal tube drawing model but also determine its numerical solution. To perform linear stability analysis, steady state numerical solution is incorporated in the eigenvalue problem, formulated by linearizing the isothermal model. The eigenvalue problem is then solved numerically to determine the critical draw ratio which indicates the onset of instabilities. To the end, stability of the process is analyzed using three different values of space step size. We also observe and discuss the effect of density, viscosity and pressure on stability of the isothermal tube drawing model. [ABSTRACT FROM AUTHOR]

In this paper, a method for extracting parameters of planar artificial transmission line is proposed. On the one hand, the Z parameters are solved by S parameters, and then the equivalent circuit parameters are obtained directly by S parameters through the relationship between Z parameters and lumped elements of equivalent network model. On the other hand, the expressions for calculating attenuation constant α, phase shift constant β and characteristic impedance Zc of transmission line by S parameters are obtained, which are planar artificial transmission. Mathematical methods for analysis of transmission line model and parameter extraction and summary. [ABSTRACT FROM AUTHOR]

Non-standard fuzzy sets play a significant role in uncertainty modeling. In addition to membership and non-membership degree, how to handle the hesitant degree is the key issue in the uncertain information process. In this paper, we model the Pythagorean fuzzy set (PFS) under the belief structure and measure its uncertainty based on fractal-based belief (FB) entropy. A novel fuzzy entropy for PFS called belief structure-based Pythagorean fuzzy (BSPF) entropy is proposed, whose effectiveness and advantages are proven based on mathematical analysis and numerical examples. A comparative analysis between BSPF entropy and other methods shows that BSPF entropy can obtain more reasonable results. Besides, a BSPF entropy-based multi-criteria decision-making (MCDM) method and a classification method are designed to solve practical problems. The experimental results demonstrate the effectiveness of these two proposed methods in solving real-world problems of decision-making and classification. • A novel entropy measure for PFSs was defined and proposed. • Comparisons made with other state-of-art approaches. • The TOPSIS method with the presented entropy measure was applied to fault diagnosis. • Medical diagnoses were more reasonable by reassigning the hesitation degree. • Performance of the classification improved with the presented entropy measure. [ABSTRACT FROM AUTHOR]

Participatory sensing system (PSS) is an emerging field of research where the fundamental idea is to employ the autonomous agents (in this paper humans) carrying smart devices, as a virtual sensor for collecting and transmitting information. The most grinding work is to motivate the human agents carrying smart devices in the data collecting process. For motivating the human agents, auction theory has played a central role with a framework to incentivize the agents in the PSS. In this line, works so far have mainly considered that there are several human agents to sell the data, and one data collecting centre to buy the data. In this paper, we propose a truthful mechanism in an online double auction environment that addresses the situation where multiple sellers and multiple buyers are present in the PSS. To the best of our knowledge, this is the first truthful mechanism in double auction setting. [ABSTRACT FROM AUTHOR]

The primary objective of IEEE 802.22 standard is to determine vacant spectrum bands available in Digital Television channel (DTV) and to utilize them for wireless rural broadband connectivity. Cognitive Radio aims at maximizing the utilization of the limited radio bandwidth while accommodating the increasing number of services and applications in Wireless networks. For cognitive radio networks to operate efficiently, Secondary Users (SU) should be able to exploit radio spectrum that is unused by the primary user. A critical component of cognitive radio is thus spectrum sensing. The secondary user should sense the spectrum efficiently, utilize the opportunities for transmission, and vacate the channel once primary user reoccupies it. In this paper, we propose approaches for cooperative spectrum sensing as per the IEEE 802.22 standard. This paper describes several simulation scenarios that can be used to evaluate spectrum sensing by single SU unit (local sensing) and multiple SUs in a cooperative setup. The detection accuracy and performance of the proposed algorithms are described using performance metrics called probability of detection and probability of false-alarm through extensive simulations using Matlab. [ABSTRACT FROM AUTHOR]

Today's automatic visual surveillance is prime need for security and this paper presents first step in the direction of automatic visual gun detection. The objective of our paper is to develop a framework for visual gun detection for automatic surveillance. The proposed framework exploits the color based segmentation to eliminate unrelated object from an image using k-mean clustering algorithm. Harris interest point detector and Fast Retina Keypoint (FREAK) is used to locate the object (gun) in the segmented images. Our framework is robust enough in terms of scale, rotation, affine and occlusion. We have implemented and tested the system over sample images of gun, collected by us. We got promising performance of our system to detect a gun. Further, our system performs very well under different appearance of images. Thus our system is rotation, scale and shape invariant. [ABSTRACT FROM AUTHOR]

Abstract In this paper, a detailed mathematical analysis of the optimality of the premise and consequent parts of the recently introduced first-order Autonomous Learning Multi-Model (ALMMo) neuro-fuzzy system is conducted. A novel self-boosting algorithm for structure- and parameter-optimization is, then, introduced to the ALMMo, which results in the self-boosting ALMMo (SBALMMo) neuro-fuzzy system. By minimizing the objective functions with the previously collected data, the SBALMMo is able to optimize its system structure and parameters in few iterations. Numerical examples based benchmark datasets and real-world problems demonstrate the effectiveness and validity of the SBALMMo, and show the strong potential of the proposed approach for real applications. Highlights • A systematic analysis of the optimality of the ALMMo neuro-fuzzy system is conducted. • A novel self-boosting algorithm for structure and parameter-optimization is proposed. • The self-boosting ALMMo (SBALMMo) neuro-fuzzy system is introduced. • The effectiveness and validity of the SBALMMo are demonstrated on real world problems. [ABSTRACT FROM AUTHOR]

Abstract This paper proposes a novel constraint-handling mechanism, namely the angle-based constrained dominance principle (ACDP), to solve constrained multi-objective optimization problems (CMOPs). In this work, the mechanism of ACDP is embedded in a decomposition-based multi-objective evolutionary algorithm (MOEA/D). ACDP uses the angle information among solutions of a population and the proportion of feasible solutions to adjust the dominance relationship, so that it can maintain good convergence, diversity and feasibility of a population, simultaneously. To evaluate the performance of the proposed MOEA/D-ACDP, fourteen benchmark instances and an engineering optimization problem are studied. Six state-of-the-art CMOEAs, including C-MOEA/D, MOEA/D-CDP, MOEA/D-Epsilon, MOEA/D-SR, NSGA-II-CDP and SP, are compared. The experimental results illustrate that MOEA/D-ACDP is significantly better than the other six CMOEAs on these benchmark problems and the real-world case, which demonstrates the effectiveness of ACDP. Highlights • The proposed MOEA/D-ACDP utilizes the angle information to maintain the diversity. • MOEA/D-ACDP enhances convergence to the PF by exploring infeasible regions. • MOEA/D-ACDP is significantly better than the other six CMOEAs on the benchmark problems. [ABSTRACT FROM AUTHOR]

Abstract The operation processes for thermal power plant are measured by the real-time data, and a large number of historical interval data can be obtained from the dataset. Within defined periods of time, the interval information could provide important information for decision making and equipment maintenance. Actual load is one of the most important parameters, and the trends hidden in the historical data will show the overall operation status of the equipments. However, based on the interval grey parameter numbers, the modeling and prediction process is more complicated than the one with real numbers. In order not lose any information, the geometric coordinate features are used by the coordinates of area and middle point lines in this paper, which are proved with the same information as the original interval data. The grey prediction model for interval grey number by the fractional-order accumulation calculus is proposed. Compared with integer-order model, the proposed method could have more freedom with better performance for modeling and prediction, which can be widely used in the modeling process and prediction for the small amount interval historical industry sequence samples. Highlights • The interval grey model is proposed from fractional accumulation attitudes. • The modeling and prediction process are analyzed by the interval grey model. • The proposed model is applied in the interval actual load dada of the thermal power plant. [ABSTRACT FROM AUTHOR]

Abstract An observer-based fractional order anti-saturation adaptive backstepping control scheme is proposed for incommensurate fractional order systems with input saturation and partial measurable state in this paper. On the basis of stability analysis, a novel state observer is established first since the only information we could acquire is the system output. In order to compensate the saturation, a series of virtual signals are generated via the construction of fractional order auxiliary system. Afterwards, the controller design is carried out in accordance with the adaptive backstepping control method by introduction of the indirect Lyapunov method. To highlight the effectiveness of the proposed control scheme, simulation examples are demonstrated at last. Highlights • The output feedback is adopted via a fractional order observer. • A fractional order auxiliary system is constructed to compensate the saturation. • The adaptive backstepping control is applied for the incommensurate fractional order plant. • Nonlinear feedback adds more degree of freedom to controller design. • Besides the goals of stabilization, our proposed method achieves the asymptotic tracking. [ABSTRACT FROM AUTHOR]

Abstract Universal block diagram based schemes are proposed for modeling and simulating the fractional-order control systems in this paper. A fractional operator block in Simulink is designed to evaluate the fractional-order derivative and integral. Based on the block, the fractional-order control systems with zero initial conditions can be modeled conveniently. For modeling the system with nonzero initial conditions, the auxiliary signal is constructed in the compensation scheme. Since the compensation scheme is very complicated, therefore the integrator chain scheme is further proposed to simplify the modeling procedures. The accuracy and effectiveness of the schemes are assessed in the examples, the computation results testify the block diagram scheme is efficient for all Caputo fractional-order ordinary differential equations (FODEs) of any complexity, including the implicit Caputo FODEs. Highlights • A fractional operator block is designed for evaluating fractional-order derivative and integral, the fractional-order control systems with zero initial conditions can also be modeled conveniently with the block. • For the fractional-order control systems described by Caputo fractional-order ordinary differential equations (FODEs), the compensation scheme and the integrator block chain scheme are proposed. The equations of any complexity can be modeled and solved with these schemes, including the implicit Caputo FODEs which cannot be handled with the existing numerical algorithms. • The fractional-order control systems with nonzero initial conditions can be modeled and solved with the proposed schemes, while this kind of the systems cannot be handled with the existing MATLAB toolboxes. • The scheme is convenient and intuitive, therefore it is very practical in handling the simulation problems in fractional-order control systems. [ABSTRACT FROM AUTHOR]

Highlights • Applying a novel evolutionary optimization algorithm namely MCSA to ELD problem. • Proposing two modification methods for improving the CSA performance. • Applying the MCSA to five well-known ELD test systems. • Employing four well-known benchmark functions to verify the MCSA. • Addressing the MCSA as a highly competitive with some previous algorithms. Abstract This paper presents a novel evolutionary optimization algorithm namely the modified crow search algorithm (MCSA) for solving the non-convex economic load dispatch (ELD) problem which improves the crow search algorithm (CSA) by an innovative selection of the crows and adaptive adjustment of the flight length. MCSA is a population-based technique based on the intelligent behavior of the crows in finding food sources. In MCSA, each crow saves its food in hiding-places for the time it needs. Also, each crow searches environment to find the better foods by stealthily following other crows to discover their hiding-places. The proposed MCSA develops the search capability of crows in the original CSA and introduces a new way by which a destination is selected by a crow to follow. To indicate the applicability of MCSA in the ELD problem, it is applied on five different well-known test systems. The results are compared in terms of the solution quality, robustness, and computing time with other methods implying that the proposed method has a superior performance than the other techniques. [ABSTRACT FROM AUTHOR]

This paper addresses design of model predictive control (MPC) for dynamic systems in the presence of disturbances. For the systems with disturbances, it is common to use observers to estimate states and disturbances, allowing control algorithm to reject disturbances. In this paper, we demonstrate how one can extend model predictive control for systems with disturbances by applying full state and disturbance observer. To this aim, a two-stage approach is proposed where the observer design procedure is completely decoupled from the MPC problem, known as the separation principle. We focus on the decoupling principal and it is shown that the observer can be designed independently via a norm minimization problem to reduce effects of disturbances and model mismatch. On the other hand, the MPC law is obtained using the multi-parametric quadratic programming approach where the parameters are the components of the state vector. [ABSTRACT FROM AUTHOR]

This research paper focuses on the design and development of simplified RTDA control law computation formulae for SOPDT process with minimum or non-minimum zero. The design of RTDA control scheme consists of three main components namely process output prediction, model prediction update and control action computation. The systematic approach for computation of the above three components for SOPDT process with minimum or non-minimum zero is developed in this paper. The design, implementation and performance evaluation of the developed controller is demonstrated via simulation examples. The closed loop equation, block diagram representation and theoretical stability derivation for RTDA controller are developed. The performance of proposed controller is compared with IMC, SPC, MPC and PID controller and it is demonstrated on Industrial non-linear CSTR process. [ABSTRACT FROM AUTHOR]

This paper presents a solution to the bottleneck problem with dynamic sharing or leasing of service capacities. From this perspective the use of the proposed method as a parallel element in service capacities sharing is very important, because it enables minimization of the number of interfaces, and consequently of the number of leased lines, with a combination of two service systems with time-opposite peak loads. In this paper we present a new approach, methodology, models and algorithms which solve the problems of dynamic leasing and sharing of service capacities. [ABSTRACT FROM AUTHOR]

This paper uses the Continued Fraction Expansion (CFE) method for analog realization of fractional order differ-integrator and few special classes of fractional order (FO) controllers viz. Fractional Order Proportional-Integral-Derivative (FOPID) controller, FO[PD] controller and FO lead–lag compensator. Contemporary researchers have given several formulations for rational approximation of fractional order elements. However, approximation of the controllers studied in this paper, due to having fractional power of a rational transfer function, is not available in analog domain; although its digital realization already exists. This motivates us for applying CFE based analog realization technique for complicated FO controller structures to get equivalent rational transfer functions in terms of the controller tuning parameters. The symbolic expressions for rationalized transfer function in terms of the controller tuning parameters are especially important as ready references, without the need of running CFE algorithm every time and also helps in the synthesis of analog circuits for such FO controllers. [ABSTRACT FROM AUTHOR]

Split cuts are among the most important and well-understood cuts for general mixed-integer programs. In this paper we consider some recent generalizations of split cuts and compare their relative strength. More precisely, we compare the elementary closures of split, cross, crooked cross and general multi-branch split cuts as well as cuts obtained from multi-row and basic relaxations. We present a complete containment relationship between the closures of split, rank-2 split, cross, crooked cross and general multi-branch split cuts. More specifically, we show that 3-branch split cuts strictly dominate crooked cross cuts, which in turn strictly dominate cross cuts. We also show that multi-branch split cuts are incomparable to rank-2 split cuts. In addition, we also show that cross cuts, and hence crooked cross cuts, cannot always be obtained from 2-row relaxations or from basic relaxations. Together, these results settle some open questions raised in earlier papers. [ABSTRACT FROM AUTHOR]

Zeroing neural network (ZNN) is a powerful tool in designing suitable control schemes since it is a systematic approach. It has been used in fields like robot manipulator control and tracking control, but few researchers have investigated the possible application of the ZNN in multi-agent systems. Based on the elegant zeroing neural network (ZNN) scheme, in this paper, two novel noise-tolerant ZNN (NTZNN) models are proposed to achieve consensus, which is a crucial problem in the field of cooperative control of the multi-agent systems. Besides, the novel noise-tolerant sign-bi-power (NTSBP) and noise-tolerant sign-exp-power (NTSEP) activation functions are used in this study. The NTZNN models activated by NTSBP and NTSEP are more robust than traditional ZNN models activated by the traditional sign-bi-power (SBP) and sign-exp-power (SEP) activation functions, respectively. The detailed mathematical analysis is presented to prove the robustness and predefined-time stability of the NTZNN models, and the upper bounds of the settling-time function are also estimated by a novel method based on improper integral. Combining the traditional Polyakov method and the proposed method based on improper integral, we can estimate the upper bounds of the settling-time function in a more precise way. Then, the robustness of the NTZNN models under both dynamic bounded vanishing noise and dynamic bounded non-vanishing noise is further evaluated by numerical experiments, and results show that the models are effective at both situations. We also present several practical examples of formation control, and parallel experiments are provided to further demonstrate that our results are general. All the theoretical and numerical verification results show that the NTZNN models are more robust than the traditional ZNN models activated by SBP or SEP activation functions, and it is also predefined-time stable. • This study provides an insight into the application of ZNN in networked control systems. • Two NTZNN models are proposed to solve the consensus problem under various noise. • Settling-time functions are estimated through a novel improper integral based method. • The proposed protocal are verified in MAS with fixed and switching communication topology. • We also verify our protocol in practical formation control experiments. [ABSTRACT FROM AUTHOR]

The fractional complex Ginzburg–Landau model is widely used in the description of wave propagation through optical transmission lines. It has many useful applications in the fields of telecommunications and nonlinear optics. This paper investigates the fractional effects of the complex Ginzburg–Landau model with quadratic–cubic, anti–cubic and generalized anti–cubic laws of nonlinearity by using generalized projective Riccati equation method. The variation in the traveling wave behavior of the governing model is examined for beta, conformable and M-truncated derivatives. Some constraint conditions are carried out during mathematical analysis, which are further used for evaluating the traveling wave solutions. The analytic solutions of the considered model are determined in terms of hyperbolic and trigonometric function solutions. Consequently, dark, bright, kink, bell-shaped and singular solitons are extracted. The reported solutions are presented using 2D and 3D graphs. These graphs are showing the fractional effects for different values of fractional parameter. The evolution of the wave profiles shows that the retrieved solitons become similar for all three definitions of fractional derivatives as the fractional parameter approaches unity. [ABSTRACT FROM AUTHOR]

Abstract: Wireless Sensor Networks (WSNs) have been utilized by many critical applications such as military and health care monitoring. Such applications require special Quality of Service (QoS) treatment. However, the components of sensor nodes suffer from different limitations including the scarce energy source, limited processing capabilities, and limited storage space. At the same time, nodes are supposed to live for long time. This could occur when the energy is balanced on the active nodes in the network. This paper handles the problem of QoS in Wireless Sensor Networks (WSNs). The paper considers the limitation of the nodes in handling many messages at the same time especially the sink node. Therefore, nodes can coordinate with each other to minimize the number of dropped message. Defining some nodes to send to the sink node at certain time allows other nodes to go to sleep. Certainly, this QoS control enhances the operation of the network and positively affect the nodes’ consumed energy. This work applies one of the game theory schemes which is Gur game. The paper proposes two QoS control techniques with Quick Convergence called Periodic Gur Game (PGur) and Adaptive Periodic Gur Game (APGur). These two approaches are evaluated using different sets of experiments. [Copyright &y& Elsevier]

Abstract In this paper, the fractional Riccati method is modified for solving nonlinear variable coefficients fractional differential equations involving modified Riemann–Liouville derivative. This approach is successfully applied to the variable coefficient space–time fractional Korteweg de Vries (vcSTFKdV) equation. Variety of analytical solutions are obtained. The validity of this approach is discussed. The arbitrariness of the non-integer derivative order α possesses much richer structures. The amplitude increases when the non-integer derivative order increases such that 0.1 < α ⩽ 1. While it decreases the non-integer derivative order increases such that 0 < α < 0.1. From the graphical presentation of the obtained solutions it is observed that changing the non-integer derivative order value α affects the soliton behavior in a fundamental way; therefore, the non-integer derivative order can modify the wave shape without changing the properties of the medium, the nonlinearity and the dispersive effects. [ABSTRACT FROM AUTHOR]

Let k , n denote two positive integers and consider the family of the polytopes defined as the convex hull of pairs of the form ( Y , h ) where Y is a 0/1-matrix with k rows, n columns, containing exactly one nonzero coefficient per column, and where h stands for the smallest index of a nonzero row of Y . These polytopes and some variants naturally emerge in formulations of different classical combinatorial optimization problems such as minimum makespan scheduling and minimum span frequency assignment. In this paper, we provide complete formulations for these polytopes and show the associated separation problem can be solved in polynomial time. The complete formulations in the original space of variables generally contain an exponential number of inequalities. Alternative extended compact formulations are also presented. [ABSTRACT FROM AUTHOR]

This paper investigates both the ordinal and multiplicative consistencies for reciprocal preference relations simultaneously. First, the relationship among ordinal consistency, acceptable cardinal consistency and perfect cardinal consistency of reciprocal preference relations are analyzed. Then, based on the basic forms of all ordinal inconsistencies, i.e. 3-cycle cases, a new ordinal consistency index, called OCI ( R ),is introduced to measure the degree of ordinal consistency for reciprocal preference relations. An algorithm to identify and modify ordinal inconsistent elements in reciprocal preference relations is further developed. Afterwards, a multiplicative inconsistency identification and modification method is developed, in which an induced matrix is constructed on the basis of multiplicative consistency property, to improve the consistency of reciprocal preference relations. Meanwhile, some numerical examples are illustrated to show the effectiveness and efficiency of the developed methods Compared with the existing methods, our proposed methods not only significantly improve both the ordinal and multiplicative consistency but also are appropriate for both strict and non-strict reciprocal preference relations, meanwhile retaining the original preference information as much as possible. [ABSTRACT FROM AUTHOR]

A consensus reaching process is an iteratively developed negotiation process designed to ensure that a mutual agreement is reached by decision makers. To incorporate distribution information of hesitant fuzzy sets, probability-hesitant fuzzy sets have recently been proposed. In the context of probability-hesitant fuzzy preference relations (PHFPR), this paper aims to provide a novel consensus reaching process for group decision making problems. By means of fuzzy preference relations, an optimization based consistency improvement process is proposed to deal with the inconsistencies in a given PHFPR. Consensus measures that are developed based on the distances between the individuals are computed on three levels: an alternative pair level, an alternatives level, and a preference relations level. An algorithm that adopts a local feedback strategy is designed to improve the consensus reaching process. The feedback strategy sequentially identifies the preferences with respect to the position and the anti-ideal individuals who need to change, after which the convergence of the proposed algorithm is proven. The novelty of the proposed strategy is that it avoids the need to compute the collective preference relations and recommendations are generated for the individuals in their original domains. Finally, some numerical examples taken from the literature are given to compare the proposed approaches with existing studies. The obtained results confirm the theoretical analysis and highlight the advantages of the proposed approaches. [ABSTRACT FROM AUTHOR]

In this paper, a robust controller is designed for variable speed wind turbine (VSWT) system. The VSWT is an uncertain system having nonlinear dynamics. The irregular behavior of wind makes the system unstable. To overcome this problem, a nonlinear robust controller is designed using quasi-sliding mode approach (QSMC). The chattering effect is almost eliminated from the overall system. The obtained results are validated through simulation studies. The simulation results are compared with the conventional sliding mode controller to show the superior performance of the proposed control scheme. [ABSTRACT FROM AUTHOR]

This paper presents two major aspects of Frege's and Peirce's views on assertion and denial: first, their arguments for the notational choices concerning the representation of assertion and denial in Begriffsschrift (BS) and Existential Graphs (EGs), respectively; and second, those properties of BS and EGs which reflect their inventors' views on assertion and denial. We show that while Frege's notation has an ad hoc sign of assertion and an ad hoc sign of negation, Peirce has a sign of assertion which is also a sign of logical conjunction, and a sign of scope which is also a sign of negation. [ABSTRACT FROM AUTHOR]