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To review the present scenario of the research on the scheduling and control of the production process in the manufacturing industry, this comprehensive article has extensively examined this field's hotspots, boundaries, and overall evolutionary trajectory. This paper's primary goal is to visualize and conduct an organized review of 5052 papers and reviews that were published between 2002 and 2022. To reveal the "social, conceptual, and conceptual framework" of the production area, identify key factors and research areas, highlight major specialties and emerging trends, and conduct research, countries, institutions, literature keywords, etc., are all used. Additionally, research methodologies are always being improved. The aim of this work is to explore more references for research implementation by analyzing and classifying the present research status, research hotspots, and potential future trends in this field of research. [ABSTRACT FROM AUTHOR]

This paper investigates the issue of asynchronous H∞ tracking control for nonlinear semi-Markovian jump systems (SMJSs) based on the T-S fuzzy model. Firstly, in order to improve the performance of network control systems (NCSs) and the efficiency of data transmission, this paper adopts a double quantization strategy which quantifies the input and output of the controllers. Secondly, for the purpose of reducing the burden of network communication, an adaptive event-triggered mechanism (AETM) is adopted. Thirdly, due to the influence of network-induce delay, the system mode information can not be transmitted to the controller synchronously, thus, a continuous-time hidden Markov model (HMM) is established to describe the asynchronous phenomenon between the system and the controller. Additionally, with the help of some improved Lyapunov-Krasovski (L-K) functions with fuzzy basis, some sufficient criteria are derived to co-guarantee the state stability and the H∞ performance for the closed-loop tracking control system. Finally, a numerical example and a practical example are given to verify the effectiveness of designed mentality. [ABSTRACT FROM AUTHOR]

Snake robots have redundant kinematic structure which predetermines them for motion in rough and unstructured terrain with obstacles, narrow spaces or environments with different ground levels. Dynamic modeling of snake robots is an important element in the development of control strategies for them. This paper, deals with the dynamic model of a snake robot moving in a pipeline. The model is based on Newton's mechanics with consideration of the viscous as well as Coulomb friction model. The paper uses Hertz theory for modeling of contact between a snake robot and side walls of a pipeline. Based on optimization process results, the friction effects as well as analyses of snake robot propulsive force are investigated. The main contributions of the paper are the developed dynamic model for snake robot motion in a pipeline, open source code of the developed model in MATLAB, and analyses of individual parameters of snake robot motion. • Propulsive force of snake robot moving in a pipeline is significantly affected by friction of the side walls. • One full sine wave formed by snake robot links ensures maximum average velocity. • Considering Coulomb friction the snake robot performs more jerked motion in comparison with viscous friction. [ABSTRACT FROM AUTHOR]

This paper examines the specifics of studying the dynamics of the behavior of the host and the parasitoid in two dynamic systems. The host model HPM is an extension to a 2D system, where an arctan function acts as an activation function. It was chosen because it can be used in artificial neural networks of intelligence. Thus, the modeling process leads to the following representation of the essence of this model: the population dynamics in the main plane occur over discrete time intervals and by several formulae. These equations were originally intended to describe the interaction between the host and the parasitoid. The model took the derivatives of a sigmoid in arctan function to show the slope of a sigmoid in any given pair was done by tangents and normalized the output to one during training. Lastly, we have a stability analysis of the system: to comma and an R locus for the fixed points by the Jacobian matrix eigenvalues of the model have been given, so the type behavior of this model is described. Also, domestication is the chaos for this model: a 2D controlled low can stabilize a given system. We presented a new concept of applying the HPM system as the activation function in AI binary medical image classification: SPECT Heart data. HPM system outperforms the traditional sigmoid function extensively which can improve the accuracy and quality of image classification within and outside the applicability spectrum. [ABSTRACT FROM AUTHOR]

Model predictive control (MPC) performance depends on the accuracy of the system model. Moreover, the optimization algorithm of MPC requires numerous online computations. These inherent limitations of MPC hinder its application in power electronics systems. This paper proposes a two-part solution for these challenges for a three-phase inverter with an output LC filter. The first part of the control scheme is a linear and modified model-free approach based on the auto-regressive structure (ARX) with exogenous input. The second part is the computationally efficient optimization algorithm based on the active set method to solve the optimization problem of the MFPC. The objective of the control scheme is to regulate the output voltages of the inverter in the presence of constraints. The constraints are the maximum admissible filter current and optimal duty cycle to avoid any damage to the system. To validate the performance of the proposed control scheme, simulations and hardware-in-loop (HIL) real-time investigations have been performed, comparing the results of the proposed approach with the model-based predictive control. The results showcase the computational efficiency and effectiveness of the MFPC approach, demonstrating its potential for overcoming the limitations of traditional MPC in power electronics systems. [ABSTRACT FROM AUTHOR]

This paper presents a new third-order symmetric difference equation transformed into a 3D discrete symmetric map. The nonlinear dynamics and symmetry of the proposed map are analyzed with two initial conditions for exploring the sensitivity of the map and highlighting the influence of the map parameters on its behaviors, thus comparing the findings. Moreover, the stability of the zero fixed point and symmetry are examined by theoretical analysis, and it is proved that the map generates diverse nonlinear traits comprising multistability, chaos, and hyperchaos, which is confirmed by phase attractors in 2D and 3D space, Lyapunov exponents ( L E s ) analysis and bifurcation diagrams; also, 0-1 test and sample entropy (SampEn) are used to confirm the existence and measure the complexity of chaos. In addition, a nonlinear controller is introduced to stabilize the symmetry map and synchronize a duo of unified symmetry maps. Finally, numerical results are provided to illustrate the findings. [ABSTRACT FROM AUTHOR]

This paper focuses on the urgent issue of minimising the impact of pollutants on aquatic life in river ecosystems. Our innovative approach involves the integration of mathematical modelling and strategic control methods to counteract the negative consequences of industrial and agricultural activities. The model, developed in a one-dimensional context, captures the complex dynamics of species population and pollutant concentration. Using an optimisation framework, we strive to achieve a harmonious balance that limits pollution, enhances species diversity and optimises control expenditure. Ultimately, we seek to harmonise industrial progress with ecological vitality, promoting the sustainability of river ecosystems for generations to come. [ABSTRACT FROM AUTHOR]

In early 2020, the spread of COVID-19 resulted in the wide use of online classes in China. Drawing on Foucault’s disciplinary power and De Certeau’s strategy-tactic dialectic, this paper explores the online learning practice of students in a rural junior middle school at Yu Town in Central China during the pandemic, through interviewing the students, teachers, and parents. The findings show that the teachers and the students engaged in a power game in online education and employed a series of strategies and tactics to realize the control and resistance through the creative use of media technologies. The study reveals the paradox that the rural students’ agency and resistance, enabled by the media technologies, may result in negative consequences for their learning and further broaden the gap between rural and urban students, thus reproducing the system that they are dissatisfied with. [ABSTRACT FROM AUTHOR]

This paper introduces a new symmetric fractional-order discrete system. The dynamics and symmetry of the suggested model are studied under two initial conditions, mainly a comparison of the commensurate order and incommensurate order maps, which highlights their effect on symmetry-breaking bifurcations. In addition, a theoretical analysis examines the stability of the zero equilibrium point. It proves that the map generates typical nonlinear features, including chaos, which is confirmed numerically: phase attractors are plotted in a two-dimensional (2D) and three-dimensional (3D) space, bifurcation diagrams are drawn with variations in the derivative fractional values and in the system parameters, and we calculate the Maximum Lyapunov Exponents (MLEs) associated with the bifurcation diagram. Additionally, we use the C 0 algorithm and entropy approach to measure the complexity of the chaotic symmetric fractional map. Finally, nonlinear 3D controllers are revealed to stabilize the symmetric fractional order map's states in commensurate and incommensurate cases. [ABSTRACT FROM AUTHOR]

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We consider systems with unboundedly many processes that communicate through shared memory. In that context, simple verification questions have a high complexity or, in the case of pushdown processes, are even undecidable. Good algorithmic properties are recovered under round-bounded verification, which restricts the system behavior to a bounded number of round-robin schedules. In this paper, we extend this approach to a game-based setting. This allows one to solve synthesis and control problems and constitutes a further step towards a theory of languages over infinite alphabets. [ABSTRACT FROM AUTHOR]

Simple Summary: Foot-and-Mouth Disease is one of the most relevant animal diseases and remains of global concern. The World Organization for Animal Health has specified two sanitary statuses that assure freedom from Foot-and-Mouth Disease: "Foot-and-Mouth Disease-free with vaccination" and "Foot-and-Mouth Disease-free without vaccination". Over the recent decades, technological improvements in vaccines and diagnostics allow demonstration of freedom from virus circulation regardless of vaccination status. Therefore, the distinction between the two Foot-and-Mouth Disease-free statuses is outdated and no longer appropriate. The authors present their collective view on the position of recognizing both Foot-and-Mouth Disease-free statuses as equivalent in terms of sanitary protection guarantees. This will be made clear by highlighting how Foot-and-Mouth Disease freedom is achieved and how vaccines, diagnostic tools, and disease control capacity have improved, allowing reliable demonstration of freedom from Foot-and-Mouth Disease virus circulation. The prerequisites to recognizing the two statuses as equivalent, as well as disease control issues, will be discussed. They further illustrate that Foot-and-Mouth Disease-free status with vaccination can be considered Foot-and-Mouth Disease-free with active prevention. Recognizing the two Foot-and-Mouth Disease statuses as equivalent will allow countries to choose if they aim for freedom with or without vaccination, based on their national and regional epidemiological risk and without compromising the safety of the production system. Foot-and-Mouth Disease (FMD) is still one of the most relevant animal diseases and remains of global concern. The World Organization for Animal Health (WOAH) has specified two sanitary statuses that assure freedom from FMD: a country or zone can be free from FMD either with or without vaccination. To obtain either of the two statuses, absence of virus circulation must be shown. The standards set by WOAH are used for trade negotiations. During recent decades, different tools and approaches were developed to control FMD, including vaccines, diagnostics, and the Progressive Control Pathway for FMD. These tools improved over time, and nowadays high-quality, reliable vaccines and specific diagnostics are available to efficiently control and detect the infection, even in vaccinated populations. Due to these improvements, it is no longer justifiable to treat the two FMD-free statuses differently. The distinction between the statuses provides wrong incentives and tempts countries to take increased risks by stopping vaccination to improve their trade conditions, which can have potentially devastating consequences. The decision to stop vaccination should only be made on the basis of a careful and comprehensive analysis of the local and regional epidemiological situation. This paper presents the perspective that member countries and WOAH should recognize the two FMD-free statuses as equivalent. [ABSTRACT FROM AUTHOR]

EDITORIAL published: 22 March 2021 doi: 10.3389/fnbot.2021.671519 Frontiers in Neurorobotics | www.frontiersin.org 1 March 2021 | Volume 15 | Article 671519 Edited and reviewed by: Jae-Ho Han, Korea University, South Korea *Correspondence: Jose de Jesus Rubio rubio.josedejesus@gmail.com Received: 24 February 2021 Accepted: 01 March 2021 Published: 22 March 2021 Citation: Rubio JdJ, Pan Y, Pieper J, Chen M-Y and Sossa Azuela JH (2021) Editorial: Advances in Robots Trajectories Learning via Fast Neural Networks. The paper titled "CNN Based Detectors on Planetary Environments: A Performance Evaluation" by Furlán et al. presents a convolutional neural network algorithm and an exploration robot for the detection of rocks in environments similartoMars. Some examples of fast neural networks, and their variants, are long short-term memory, convolutional neural network, recurrent neural network, deep deterministic policy gradient, cascade neural network, genetic algorithm, machine learning, and fuzzy model. [Extracted from the article]

Background: The concept of control has long been suggested as a central factor in eating disorder (ED) aetiology. The concept is now so mainstream that it risks being used in a potentially reductionist, stigmatising or otherwise harmful manner. In this paper, we explore and discuss our positions on the use of control-related terminology for EDs. Methods: The authors of this auto-ethnographic position paper include academic researchers, individuals with lived experience and clinicians (not mutually exclusive). In sharing our experiences and observations, we aim to raise awareness of the wider impacts that control framing can have on ED perceptions, treatment, recovery and individuals' lived experience. Results: We argue that although control can play a role in some ED experiences, an overemphasis upon this factor to the exclusion of other conceptualisations is not beneficial. Conclusions: To mitigate against pathologisation of an individual, it is important to challenge a discourse that can lead to EDs being perceived as something 'wrong' with the individual, rather than a consequence of life events or other environmental influences. We identify priorities for the future for researchers, clinicians, policy makers and the wider public. Plain English summary: Control has often been described as a central factor within Eating Disorders (EDs). Whilst control can play a role in ED experiences, we argue that overemphasis upon this factor can result in other important factors being overlooked. For many individuals, EDs are the consequence of life events and/or other environmental influences. With this in mind, discourse which overemphasises control (e.g., rather than coping) can inaccurately portray EDs as something 'wrong' with the individual. It is important to challenge this discourse to encourage more appropriate perceptions of EDs. In turn, this could improve understanding and treatment of EDs, reduce stigma, and promote recovery. [ABSTRACT FROM AUTHOR]

Tuned mass dampers (TMDs) are commonly used to mitigate vibrations in civil structures. There is a growing demand for new solutions that offer similar effectiveness as TMDs but with reduced mass. In this context, this paper investigates active (ATMD) and semi-active (STMD) tuned mass dampers with relative displacement and velocity feedback. The control force of the ATMD is assumed to be the sum of viscous damping and either positive or negative stiffness forces. This control force is calibrated for a specific parameter K such that the effectiveness of the ATMD in reducing harmonic vibrations matches that of the TMD with K times larger mass. The optimal calibration is derived based on the mathematical reformulation of an existing optimal acceleration feedback control algorithm. The control approach for the ATMD is then applied to the STMD. Subsequently, the sub-optimal STMD is analyzed, with a focus on its limitations arising from the clipping of active forces. Finally, the paper presents a calibration of the STMD using a numerical optimization method. It is demonstrated that the maximum achievable performance of the numerically optimized STMD matches that of the TMD with three times larger mass. [ABSTRACT FROM AUTHOR]

Small–size (desktop) robot arms are being increasingly used in research and education, where low–cost implementation prevails over the need for high dynamic performance. This paper presents a design of a control unit for a 6DoF desktop robot arm with cylindrical joints actuated with stepper motors. Feedforward control, often chosen as a control strategy for stepper motors due to the simplicity of control algorithms, as well as the cost–effectiveness of the solution, is selected as the control method. The applicative software with GUI developed in Matlab is presented. A trajectory planner based on the solution of the inverse kinematics problem and the user–selected joint velocity profile is implemented. In order to avoid step skipping occurrence, the torque in joints necessary to produce the programmed joints motion have to be achievable by the installed stepper motors. As a part of applicative software, the check on the feasibility of the programmed robot trajectories by numerical simulation of solution of inverse dynamics problem in Simscape Multibody is performed. The microcontroller is used as an interface device that controls the stepper motor drivers. The applicative software communicates with the microcontroller using the TCP protocol. [ABSTRACT FROM AUTHOR]

This paper considers a class of systems called density systems. For such systems, the derivative of a quadratic function depends on some function termed the density function. The latter function is used to define the properties of the space affecting the behavior of the systems under consideration. The role of density systems in control law design is shown. Control systems are constructed for plants with known and unknown parameters. The theoretical results are illustrated by numerical simulation. [ABSTRACT FROM AUTHOR]

Wheeled field robots have promising widespread civil and military applications in off-road conditions. The complex off-road working conditions pose substantial challenges in applying field robots, especially the newly emerged fully autonomous “smart” mobile ground robots without human intervention. Two key issues arise for a successful navigation, namely geometrical and non-geometrical obstacles. So far, most of the research on off-road mobile robots has focused on approaches to avoid geometrical obstacles by ignoring the influence of wheel slippage on the robot mobility. On the other hand, wheel slippage plays a key role in the performance of off-road mobile robots and must be addressed. The purpose of this paper is to summarize the methods in the study on the wheel slippage estimation and modeling of off-road mobile robots, along with the control and sensing technology, and report the state-of-the-art in this research field. Multiple approaches: proprioceptive-sensor-based, exteroceptive-sensor-based, model-based slippage estimation and compensation methods will be discussed. In addition, this paper also investigates the new research trend of developing machine learning methods to predict and compensate for the wheel slippage under complex working conditions. Current technical challenges and room for further research improvement are also generalized. This paper will help researchers new in this field to be familiar with the wheel slippage modeling, control and sensing technology, and inspire for the next-generation robot design that can help address the wheel slippage issues. [ABSTRACT FROM AUTHOR]