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This paper synthesises a recent research that includes opinion dynamics models and experiments suggested by the model results. The mathematical analysis establishes that the model's emergent behaviours derives from cognitive biases that should appear in quite general conditions. Moreover, it seems that psychologists have not yet detected these biases. The experimental side of the research therefore includes specifically designed experiments that detect these biases in human subjects. The paper discusses the role of the model in this case, which is revealing phenomena that are almost impossible to observe without its simulations. [ABSTRACT FROM AUTHOR]

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]

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

The article analyses the evolution of mathematical models used in life cycle estimation. A comparison between the different mathematical models and their areas of applicability is proposed. This analysis is generally done in terms of costs. The importance of the article lies in the proposal of a new mathematical model for estimating life cycle of power substations, compatible with current and future requirements. The study findings reveal that an optimization model can be established using the life cycle assessment method to obtain a longer lifespan, but also to minimize costs (maintenance, repairs, replacements, etc.). In order to establish a mathematical model of the life cycle of electrical substations, it is necessary to study several important design parameters and decision factors for each stage of the life cycle. Even if the paper does not provide empirical results, it must prove that it is necessary to develop a multi-algorithm optimization framework to find an adequate solution. The life cycle must be modelled according to: equipment availability technological evolution, maintenance activities, risk management, environmental protection, human error, etc. The study helps further research to build, implement and validate a robust model with development possibilities depending on the needs of the researchers. [ABSTRACT FROM AUTHOR]

This paper aims to solve two enduring challenges in existing trajectory similarity measures: computational inefficiency and the absence of the ‘uniqueness’ property that should be guaranteed in a distance function: dist(X, Y ) = 0 if and only if X = Y, where X and Y are two trajectories. In this work, we present a novel approach utilizing a distributional kernel for trajectory representation and similarity measurement, based on the kernel mean embedding framework. It is the very first time a distributional kernel is used for trajectory representation and similarity measurement. Our method does not rely on point-to-point distances which are used in most existing distances for trajectories. Unlike prevalent learning and deep learning approaches, our method requires no learning. We show the generality of this new approach in anomalous trajectory and sub-trajectory detection. We identify that the distributional kernel has (i) a data-dependent property and the ‘uniqueness’ property which are the key factors that lead to its superior task-specific performance, and (ii) runtime orders of magnitude faster than existing distance measures. [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]

The attraction and mobility of senior educational talents hinge on the talent cultivation and incentive mechanism of various enterprises. If the mechanism is imperfect, the talents will be less active and creative in work, and the enterprises will underperform in the long term. This paper combines literature review, questionnaire survey, and mathematical analysis to summarize the current situation of the cultivation and incentive mechanism of senior educational talents in an enterprise in a region, and analyze the defects of the existing mechanism. The results show that: the senior educational talents have not received sufficient compensations or incentive measures; the employees do not have a smooth promotion channel; the enterprise fails to issue clear and innovative reward policies. To address these defects, this paper proposes improvement measures and optimization schemes: To boost the enthusiasm and creativity of employees in work, the enterprises should give full play to the personal values of senior educational talents, strive to introduce more excellent talents, and establish a sound salary distribution system and reasonable promotion polices. The research results lay a theoretical basis for enterprises to cultivate and absorb the necessary senior educational talents. [ABSTRACT FROM AUTHOR]

In the existing pieces of literature about the three-coil wireless power transfer (WPT) system, a three-coil structure is proposed to increase the efficiency compared to the two-coil WPT system. The cross-coupling among three coils, compensation capacitor of the repeating coil (RPC) and the rectified load are considered incompletely. The circuit model of a three-coil WPT system with rectified load is developed by taking the cross-coupling of all coils and the compensation capacitor of RPC into consideration in this paper. The relationship among system efficiency, compensation level, and rectifier load is deduced. The detailed mathematical analysis and compensation capacitor selection of RPC are investigated to improve the system efficiency. An experimental study demonstrates that the selected compensation capacitor of RPC achieves a higher efficiency than resonant compensation in a three-coil WPT system with different cross-coupling conditions and rectifier load conditions. System efficiency is promoted from 73.9% (resonant compensation capacitor for RPC) to 84.2% (selected compensation capacitor for RPC). [ABSTRACT FROM AUTHOR]

Copyright of Revista Brasileira de Medicina do Esporte is the property of Redprint Editora Ltda. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: Bibliometrics is the use of statistical and mathematical analysis to assess research production and quality. These metrics provide important insights into the quality and impact of research by applying standardised metrics. However, there are inherent limitations in their application. Objective: We aimed to review existing bibliometric indices and assess their comparative utility in the assessment of medical researchers. We specifically aimed to evaluate the utility of the h-index in identifying young or developing medical researchers with future research potential. Method: We conducted a focussed literature review on commonly used bibliometrics. To explore the utility of these metrics we then used them to evaluate a sample of researchers from a South African medical school faculty. Researchers were ranked with the following metrics: number of publications; h-index; citations per paper; citations per paper per year; and m-index. The h-index, citations and publication counts were drawn from ResearchGate and, if not available, from Google Scholar. The top 20 researchers, based on publication count, were then analysed further. Results: We identified 145 researchers for analysis of which 37 were excluded due to an inability to obtain additional information. Higher time-dependent metrics (publication count, citation count, h-index) were directly proportional to years since first publication. Indices that corrected for time, such as the m-index, provided more insight and better discrimination in identifying younger researchers with greater research potential. Conclusion: Bibliometrics have utility as part of the assessment of academic output but may be subject to time-dependent bias. Research quality is best measured using the h-index, g-index and m-index. The h-index is limited by being time dependent and field specific and overlooks highly cited papers. Bibliometrics that account for time, such as the m-index, should be considered in the early identification of young researchers, ideally accompanied by critical peer review. [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 so-called intermediate model (IM) was applied in the paper to quantitatively describe complex trajectories. Using this model it was possible to find the proper fitting function for describing random trajectories that were recorded during the walking process performed by a volunteer. Experimental data were acquired using a three-dimensional Motion Capture system during normal gait of a healthy person on an automatic treadmill. The major aim of this research was to find if the IM is applicable to fit typical biomechanical measurement data. Motion Capture data collection is very time-consuming and requires a lot of memory, so storing movement trajectories in a parametric form helps to increase the data processing efficiency and mathematical analysis. As a result of the original treatment procedure described in this paper, we obtained a very accurate fit of the measured data. The results of this research can be used to model the movement of mechanical devices and for diagnostic purposes. [ABSTRACT FROM AUTHOR]

Retransmission in optical burst switching networks is a solution to recover data loss by retransmitting the dropped burst. The ingress node temporarily stores a copy of the complete burst and sends it each time it receives a retransmission request from the core node. Some retransmission schemes have been suggested, but uncontrolled retransmission often increases the network load, consumes more bandwidth, and consequently, increases the probability of contention. Controlled retransmission is therefore essential. This paper proposes a new controlled retransmission scheme for loss recovery, where the available bandwidth of wavelength channels and the burst lifetime are referred to as network conditions to determine whether to transmit a dropped burst. A retrial queue‐based analysis model is also constructed to validate the proposed retransmission scheme. The simulation and analysis results show that the controlled retransmission scheme is more efficient than the previously suggested schemes regarding byte loss probability, successful retransmission rate, and network throughput. [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]

This paper proposed an Integrated Random Early Detection (IRED) method that aims to resolve the problems of the queue-based AQM and loadbased AQM and gain the benefits of both using indicators from both types. The arrival factor (e.g., arrival rate, queue and capacity) and the departure factors are used to estimate the congestion through two integrated indicators. The utilized indicators are mathematically calculated and integrated to gain unified and coherent congestion indicators. Besides, IRED is built based on a new dropping calculation approach that fits the utilized congestion indicators while maintaining the intended buffer management criteria, avoiding global synchronization and enhancing the performance. The results showed that IRED, compared to RED, BLUE, ERED, FLRED, EnRED and DcRED, decreased packet delay and loss under various network status. Specifically, the results showed that in heavy and moderate traffic, the proposed IRED method outperformed the state-of-the-art methods in loss and delay by 18% and 10.6%, respectively. [ABSTRACT FROM AUTHOR]

Abstract This paper proposes a novel decomposition method based on user-preference and developed a variation of the decomposition based multi-objective optimization algorithm (MOEA/D) targeting only solutions in a small region of the Pareto-front defined by the preference information supplied by the decision maker (DM). This is particularly advantageous for solving multi-objective optimization problems (MOPs) with more than 3 objectives, i.e., many-objective optimization problems (MaOPs). As the number of objectives increases, the ability of an EMO algorithm to approximate the entire Pareto front (PF) is rapidly diminishing. In this paper, we first propose a novel scalarizing function making use of a series of new reference points derived from a reference point specified by the DM in the preference model. Based on this scalarizing function, we then develop a user-preference-based EMO algorithm, namely R-MOEA/D. One key merit of R-MOEA/D is that it does not rely on an estimation of the ideal point, which may impact significantly the performances of state-of-the-art decomposition based EMO algorithms. Our experimental results on multi-objective and many-objective benchmark problems have shown that R-MOEA/D provides a more direct and efficient search towards the preferred PF region, resulting in competitive performances. In an interactive setting when the DM changes the reference point during optimization, R-MOEA/D has a faster response speed and performance than the compared algorithms, showing its robustness and adaptability to changes of the preference model. Furthermore, the effectiveness of R-MOEA/D is verified on a real-world problem of reservoir flood control operations. [ABSTRACT FROM AUTHOR]

Abstract Grey Wolf Optimizer (GWO) algorithm is a relatively new algorithm in the field of swarm intelligence for solving continuous optimization problems as well as real world optimization problems. The Grey Wolf Optimizer is the only algorithm in the category of swam intelligence which is based on leadership hierarchy. This paper has three important aspects- Firstly, for improving the search ability by grey wolf a modified algorithm RW-GWO based on random walk has been proposed. Secondly, its performance is exhibited in comparison with GWO and state of art algorithms GSA, CS, BBO and SOS on IEEE CEC 2014 benchmark problems. A non-parametric test Wilcoxon and Performance Index Analysis has been performed to observe the impact of improving the leaders in the proposed algorithm. The results presented in this paper demonstrate that the proposed algorithm provide a better leadership to search a prey by grey wolves. The third aspect of the paper is to use the proposed algorithm and GWO on real life application problems. It is concluded from this article that RW-GWO algorithm is an efficient and reliable algorithm for solving not only continuous optimization problems but also for real life optimization problems. [ABSTRACT FROM AUTHOR]

Abstract A new model and solution for the multi-objective heterogeneous vehicle routing and scheduling problem, with energy minimizing, is presented in this paper. The concept of heterogeneities is concerned with the ownership of fleets. Ownership heterogeneities occur when the private fleet is not sufficient and the company has to rent some vehicles from external carriers to complete the shipments. A new mathematical formulation for vehicle routing problem with time windows (VRPTW) is also presented using the proposed concept of heterogeneities. Moreover, unlike prior attempts to minimize cost by minimizing overall traveling distance, the model also incorporates energy minimizing which meets the latest requirements of green logistics. This paper considers the customers' priority for servicing as well. The proposed model is interpreted as multi-objective optimization and used in two scenarios where, in the first scenario (I), the energy consumed and the total number of vehicles are minimized and the total satisfaction rate of customers is maximized. In the second scenario (II) the distance traveled by the vehicles, the total number of rental vehicles and the fuel consumed by the private vehicles are minimized and the total satisfaction is maximized. A new solution based on an evolutionary algorithm is proposed and its performance on several completely random instances is compared to the non-dominated sorting genetic algorithm II (NSGA II) and CPLEX Solver. The efficiency and effectiveness of the proposed approach is further demonstrated through several computational experiments. Highlights • Considering the ownership of vehicles and the available fleet as heterogeneous VRPTW (HVRPTW). • Considering a reduction in fuel consumption in modeling of the proposed HVRPTW. • Considering the customers' priority which are highly relevant to the customers' satisfaction level. • Using a direct interpretation of the proposed model as a multi-objective problem. • The computational experiments on data sets illustrate the efficiency and effectiveness of the proposed approach. [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]

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]

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]

In this paper, the power spectral density(PSD) for Multilevel Minimum Shift Keyed signal with modulation index h = 1/2 (M-ary MSK) are derived using the mathematical method of the Markov Chain model. At first, according to an essential requirement of the phase continuity characteristics of MSK signals, a complete model of the whole process of signal generation is built. Then, the derivations for autocorrelation functions are carried out precisely. After that, we verified the correctness and accuracy of the theoretical derivation by comparing the derived results with numerical simulations using MATLAB. We also divided the spectrum into four components according to the derivation. By analyzing these figures in the graphic, each component determines the characteristics of the spectrum. It is vital for enhanced spectral characteristics. To more visually represent the energy concentration of the main flap and the roll-down speed of the side flap, the specific out-of-band power of M-ary MSK is given. OMLCD(Optimum Maximum Likelihood Coherent Detection) of M-ary MSK is adopted to compare the signal received with prepared in advance in a code element T to go for the best. And M-ary MSK BER(Bit Error Rate) is compared with the same ary PSK (Phase Shift Keying) with M=2,4,6,8. The results show the detection method could improve performance by increasing the length of L(memory inherent) in the phase continuity. [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]

Economic and financial mathematics uses elements of mathematical analysis (N-dimensional space, rows, series, derivation, integration), probability calculus and linear algebra (vector, linear system of equations, programming) in all areas of economics. In this paper we analyse the EUR / USD exchange rate between 01/13/2017 - 02/15/2018. The sample element number of the examined data set is 420,544 (four hundred and twenty thousand five hundred and fortyfour). Name of the data: standard critical points (O, H, L, C) of a one-minute time window. Especially what we want to know about EUR / USD exchange rate? We want to know when the trend ends. When we want to know the end of a trend, we look for the inflection point of the function. The condition for the existence of the inflection point is that there exists a third-order derivative of the function and the second-order derivative at this point must be equal to zero, and that the third-order derivative must not be equal to zero. In this research we use histogram, moving average, the 12-day and 26-day averages for the study period, polynomial trend determination, the linear trend definition, the polynomial average of the examined period, the logarithmic trend and special the sixth degree polynomial for analyse and for possibility of forecasting using an econometric model. With the help of the Excel spreadsheet, it was possible to project in a certain number of steps. We made the projection for five step lengths. Forecasting has proved to be a good approach to what has actually happened, which is a good reason for us to continue working and to keep the direction we have started, to do further research in the specific field. [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]

This paper addresses the combinatorial characterizations of the optimality conditions for constrained least-squares fitting of circles, cylinders, and spheres to a set of input points. It is shown that the necessary condition for optimization requires contacting at least two input points. It is also shown that there exist cases where the optimal condition is achieved while contacting only two input points. These problems arise in digital manufacturing, where one is confronted with the task of processing a (potentially large) number of points with three-dimensional coordinates to establish datums on manufactured parts. The optimality conditions reported in this paper provide the necessary conditions to verify if a candidate solution is feasible, and to design new algorithms to compute globally optimal solutions. [ABSTRACT FROM AUTHOR]

Establishing relative coordinate system is essential for many applications of sensor networks. This paper proposes a computation scalable scheme for establishing relative coordinate system of sensor networks using distance measurements between sensors. A distributed selection algorithm is proposed to select a small number of nodes from all sensors to serve as virtual grid point and establish the grid relative coordinate system. The grid coordinate system forms the backbone of localization for static and mobile nodes, whereby the non-grid nodes can compute their positions via message exchange with their neighboring grid nodes. This paper shows by both mathematical analysis and simulations that the localization error of the scalable grid approach is upper bounded by half the grid width (i.e., the length of two adjacent grid points). The results also indicate that the precision of grid coordinate system can be adaptively adjusted by the grid width and the density of grid nodes to meet target applications. For those non-grid nodes, the results show that the localization precision of non-grid nodes would be bounded by one grid-cell error. [ABSTRACT FROM AUTHOR]

This paper considers 4--dimensional manifolds which admit a metric of any signature and examines the relationships between the metric, its Levi-Civita connection, its curvature tensor and sectional curvature function and its Weyl conformal tensor. It is shown that, with some special cases excepted (some of which will be discussed), these various curvature concepts are very closely related. The relationship between them and the holonomy group associated with the connection is also explored. Some of these results, in the case of positive definite and Lorentz signature, have been given before and so this paper will concentrate mainly on the case of neutral signature (+, +, -, -) and on the process of putting together simple arguments which cover all signatures simultaneously. [ABSTRACT FROM AUTHOR]

In this paper, we investigate the feasibility of interference alignment(IA) in signal space in the scenario of multiple cell and multiple user cellular networks, as the feasibility issue is closely related to the solvability of a multivariate polynomial system, we give the mathematical analysis to support the constraint condition obtained from the polynomial equations with the tools of algebraic geometry, and a new distribute IA algorithm is also provided to verify the accessibility of the constraint condition for symmetric system in this paper. Simulation results illustrate that the accessibility of the constraint condition is hold if and only if the degree of freedom(DoF) of each user can be divided by both the transmit and receive antenna numbers. [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, we propose a new technique for the enhancement of target detection in Wireless Sensor Networks (WSNs) in which sensor nodes are responsible for taking binary decisions about the presence or absence of a given target and reporting the output to the fusion center. We introduce the algorithm; Fail Silent Pair (FSP) to calculate global decision in the fusion center. The FSP algorithm randomly distributes all sensor nodes into pairs then considers pairs of the same local decision. Also, we present new detection and prevention methods to reduce the effect of dependent malicious sensor nodes. The detection method is based on the deception of suspicious sensor nodes with fake packets to detect a subset of the malicious sensor nodes, as these nodes eavesdrop on other sensor nodes packets to use their local decisions as a reference to build an intelligent decision. While the prevention method allows the fusion center to correct local decisions of some malicious sensor nodes with identified strategies, assisting in the increase of the accuracy of global decisions. We introduce a mathematical analysis to verify our methods, in addition to simulation experiments to validate our technique. [ABSTRACT FROM AUTHOR]

In program algebra, an algebraic theory of single-pass instruction sequences, three congruences on instruction sequences are paid atten- tion to: instruction sequence congruence, structural congruence, and behavioural congruence. Sound and complete axiom systems for the first two congruences were already given in early papers on program algebra. The current paper is the first one that is concerned with an axiom system for the third congruence. The presented axiom system is especially notable for its axioms that have to do with forward jump instructions. [ABSTRACT FROM AUTHOR]

The study is the first bibliometric analysis of the "Journal of Central Asian Studies". This journal started its publication from 1990 (a year before the disintegration of the former USSR) and 23 volumes had been published till 2016. Objectives of the study - The study aims to conduct the bibliometric analysis of the "Journal of Central Asian Studies" from 1990 to 2016 in order to identify editorial assignments, authorship patterns, and institutional productivity, geographical contribution in the journal. Methodology - The bibliometric data of the papers were manually collected from the hard copies of the journal in the excel file. Later, the data were tabulated and analysed using the simple mathematical and statistical quantitative techniques to reveal the findings. Findings - The journal published 266 papers in 23 volumes contributed by 202 authors from 55 institutions and 23 countries of the world. Prof. Abdul Majeed Matoo performed the duties of the "Chief Editor" of the maximum volumes (12) of the journal followed by Prof. G N Khaki for (3). The content analysis of the journal depicted that the research papers constitute the maximum contents (252, 94.74%) whereas book reviews (9, 3.38%), abstracts (1.13%) and reprints (2, 0.75%) are also available in little number. The authorship trends of the journal revealed that the maximum number of research papers are contributed by the single author (232, 87.22%) followed by double authors (27, 10.15%) and Triple authors (07, 2.63%) respectively. The maximum number of papers are contributed by Ajiaz A. Bandey (10) followed by M. A. Kaw (9) and G. M. Mir (8) respectively. Among the fifty five (55) academic and research institutions, the top contributing institutions are the University of Kashmir (139), Jawaharlal Nehru University (18), University of Mumbai (11), Aligarh Muslim University (9), University of Jammu (7), and Academy of Sciences, Uzbekistan (7) respectively. The regional analysis shows that twenty-three (23) countries of the world have contributed to the journal and the maximum number of papers are contributed by India (208, 78.20%) followed by Uzbekistan (8, 3.01%), Kazakhstan (7, 2.63%), USA (6, 2.26%) and Pakistan (4, 1.50%) respectively. [ABSTRACT FROM AUTHOR]

In this paper we propose a dynamic quantum tomography model for open quantum systems with evolution given by phase-damping channels. Mathematically, these channels correspond to completely positive trace-preserving maps defined by the Hadamard product of the initial density matrix with a time-dependent matrix which carries the knowledge about the evolution. Physically, there is a strong motivation for considering this kind of evolution because such channels appear naturally in the theory of open quantum systems. The main idea behind a dynamic approach to quantum tomography claims that by performing the same kind of measurement at some time instants one can obtain new data for state reconstruction. Thus, this approach leads to a decrease in the number of distinct observables which are required for quantum tomography; however, the exact benefit for employing the dynamic approach depends strictly on how the quantum system evolves in time. Algebraic analysis of phase-damping channels allows one to determine criteria for quantum tomography of systems in question. General theorems and observations presented in the paper are accompanied by a specific example, which shows step by step how the theory works. The results introduced in this paper can potentially be applied in experiments where there is a tendency to look at quantum tomography from the point of view of economy of measurements, because each distinct kind of measurement requires, in general, preparing a separate setup. [ABSTRACT FROM AUTHOR]

This paper is a review of sorting on several well-known graphs by adjacent swaps using permutation groups. Given a graph with a line, star, complete, or ring topology having n vertices (numbered from 1 to n ), we place n objects (numbered from 1 to n ) arbitrarily in such a way that exactly one object is placed on each vertex. A sorting procedure is intended to reach the target object placement in which each object i is placed on vertex i for 1 ≤ i ≤ n . Now, the problem is to find a minimum-length sequence of adjacent swaps needed to sort the initial arrangement of n objects on n vertices in the graph, which employs a known permutation sorting or permutation decomposition procedure using a generating set of a symmetric group S n . This paper reviews the existing permutation sorting and permutation decomposition procedures for sorting on graphs with line, star, complete, and ring topologies by adjacent swaps. We also provide concrete examples and our own implementation for this review paper in order to describe how abstract group-theoretical methods are used to find a minimum-length sequence of adjacent swaps needed to sort objects on those graphs. [ABSTRACT FROM AUTHOR]