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Flexible needle systems showing multiple advantages in various medical scenarios, characterized by their flexibility, ease of operation, adaptable control and navigation capabilities. This paper presents a scientometric analysis of the research advancements in flexible needle systems. The paper reviews 498 articles with various perspectives from 1997 to 2023 and conducts a scientometric study including crucial institutions, journals, and article keywords. The analysis reveals that the knowledge domain of flexible needle systems is focused on signal processing, navigation, and control. Subsequently, a thorough examination of the current key research directions in the field of flexible needles is conducted, and an analysis of the challenges faced by this field is presented. The review also provides a comprehensive and integrated knowledge mind map to establish the flexible needle system's information network. It offers valuable insights for researchers into future research directions and developments within the field of medical flexible needle systems in surgery. [ABSTRACT FROM AUTHOR]

Hardware-in-the-loop (HIL) testing is a popular control system testing method because it bridges the gap between modeling/simulation and experiments. Instead of designing a full hardware-based experiment to validate the results of a simulation, the plant hardware can be replaced with an emulator device that responds to exogenous inputs and effectively emulates the dynamic behavior of a system. This approach can be more cost-effective and modular, since the emulated plant system can be modeled in a simulation environment, implemented on a simplified piece of hardware and changed quickly without having to fabricate new parts. This paper develops the hardware and control scheme for a certain type of HIL device called a dynamic load emulator that consists of a 1-DOF linear hydraulic dynamometer equipped with in-line sensing to measure both its own position and the force exerted on it by a device-under-test. This measured force is passed to a real-time model of the emulated dynamic system. The model outputs the emulated system position, and a closed-loop controller is used to emulate this position. The emulator controller incorporates both model-based feedforward and standard feedback PI control. This paper characterizes the dynamometer-based dynamic load emulator and its controller, determining its hardware limitations and validating its capabilities when experiencing a force input from a linear spring with known parameters. Additionally, this paper demonstrates the ability of the emulator to represent the dynamics of a 1-DOF robotic joint when actuated by a pair of fluidic artificial muscles (FAMs). The primary contribution of this work is to allow for more comprehensive testing of FAM configurations, topologies, and controllers for a wide range of parameters, because the same hardware can be used to emulate multiple systems. As a result, this work will lead to more cost-effective, time-efficient, and energy-efficient designs of robotic systems and the FAMs used to actuate them. [ABSTRACT FROM AUTHOR]

Dedicating more attention to renewable energies and power electronic improvements results in increased direct current microgrids (DC MGs) application. However, DC MGs have some challenges with voltage adjustment and power sharing. To do so, a two-layer hierarchical control structure, including a new fully distributed secondary control strategy and conventional primary droop control method, is proposed and employed in this paper to share power and swiftly adjust the voltage accurately. Indeed, a distributedaveraging proportional-integral (DAPI) secondary control strategy is introduced. Another problem in DC MGs is the existence of constant power loads (CPLs), which may result in instability. To overcome the problems caused by CPLs, a term based on the output voltage of CPL is added to the proposed DAPI to prevent instability. The required control inputs are obtained using localized data of the DC bus and their neighbor's secondary control inputs inspired by cooperative control. Besides, this strategy needs no knowledge of the microgrid topology, which enhances flexibility. For validating the proposed DAPI strategy in DC MGs, an islanded DC MG is simulated in the MATLAB/SIMULINK software. Comparing the results with those obtained from another existing method proves the performance of the proposed DAPI controller under different scenarios of plug-and-play, communication failure, and load changes. [ABSTRACT FROM AUTHOR]

The problem of guaranteed closed-loop guidance to a given set at a given time is studied for a linear dynamic control system described by differential equations with a fractional derivative of the Caputo type. The initial state is a priori unknown, but belongs to a given finite set. The information on the position of the system is received online in the form of an observation signal. The solvability of the guidance problem for the control system is analyzed using the method of Osipov–Kryazhimskii program packages. The paper provides a brief overview of the results that develop the program package method and use it in guidance problems for various classes of systems. This method allows us to connect the solvability condition of the guaranteed closed-loop guidance problem for an original system with the solvability condition of the open-loop guidance problem for a special extended system. Following the technique of the program package method, a criterion for the solvability of the considered guidance problem is derived for a fractional-order system. In the case where the problem is solvable, a special procedure for constructing a guiding program package is given. The developed technique for analyzing the guaranteed closed-loop guidance problem and constructing a guiding control for an unknown initial state is illustrated by the example of a specific linear mechanical control system with a Caputo fractional derivative. [ABSTRACT FROM AUTHOR]

With the development of science and technology, robots gained their popularity in automation and industrial applications. Because of this the researchers are more focussed towards motion planning analysis of mobile robots, bipeds and humanoids. During the investigation, it was discovered that the robots are more likely to become trapped in local minima and dead ends. So, this paper aims to provide a novel hybridized artificial intelligence technique by combining the Self organizing migrating algorithm (SOMA) and Particle Swarm Optimization (PSO) for optimal path planning and control of single and multiple mobile robots in a static and dynamic environment. Different parameters of SOMA and PSO algorithm guides the robots to reach global optimized path in obstacle prone environment. The developed hybrid SOMA–PSO technique is tested in V-REP simulation environment with single and multiple robots, and the simulation outcomes have been authenticated in an experimental setup under laboratory conditions. Whenever sensors detects obstacle then the SOMA–PSO activates and negotiate with obstacles to move up to specified target. After simulation and real-time experiments the proposed novel hybrid technique is successfully achieved their target in an optimized manner. Further, a comparison analysis with its standalone techniques reveals that there is a significant improvement in navigational parameters. Again, the technique is tested against existing paper and an average improvement of 17.76% is observed by using the proposed hybrid technique. [ABSTRACT FROM AUTHOR]

This paper studies the THD and AC losses on the DC cables of offshore wind farm-based multi-terminal HVDC systems when they extract and deliver power from and to more than one connection point. In the paper, the study of a full system PLECS + Simulink model with two branches, including a wind resource, a wind turbine, a Permanent Magnet Synchronous Generator (PMSG), a Pulse Width Modulation (PWM) rectifier, a Single Active Bridge (SAB) DC–DC converter, an Input Parallel Output Series (IPOS) DC–DC converter, HVDC cables, and a simplified onshore system, is presented. It focuses on the investigation of the output ripple content of multiple DC–DC converters on DC cables under different wind conditions with different voltage and power ratings. The importance of the study is providing a general understanding of the operation of the innovative offshore wind farm-based DC system, as well as the interaction between different DC–DC converters and their influence on cable ripple content under different situations. [ABSTRACT FROM AUTHOR]

Threats in cyberspace are becoming increasingly burdensome to the users of information and communication systems. Therefore, their security constitutes a crucial part of activities conducted by operators of essential services, digital service providers, and entities providing cybersecurity services. Considering the necessity to ensure the proper protection of systems allowing activities in cyberspace, relevant entities must take actions related to supervision and control to assure compliance with the safety standards that reduce the threat of cybersecurity incidents. The main objective of this paper is to analyse the legal regulations governing the issue of supervision and control of compliance with cybersecurity standards by entities responsible for safeguarding cyberspace against threats. Moreover, the paper also aims to characterise the supervision and control mechanisms designed to ensure the safe use of information and communication systems and to discuss the powers of supervision and control authorities. The primary research method used in this paper is the doctrinal legal research method. It was applied to analyse the applicable legal regulations governing the supervision and control of activities in the sphere of securing cyberspace against attacks. In turn, the law theory method, also used in the studies whose results have been presented in this paper, allowed the assessment of actions being taken as part of supervision and control. The fact that the issues of supervision and control in cybersecurity are subject to statutory regulations should be regarded as positive. However, these legal acts exhibit certain flaws. Some provisions regulating these issues are vague, which may result in their over-interpretation, and thus contribute to, among other things, the infringement of the freedom of business activities principle for enterprises operating in the cybersecurity sector. [ABSTRACT FROM AUTHOR]

The significance of this review lies in addressing the limitations of passive locomotion in capsule endoscopes, hindering their widespread use in medical applications. The research focuses on evaluating existing miniature in vivo remote-controlled capsule endoscopes, examining their locomotion designs, and working theories to pave the way for overcoming challenges and enhancing their applicability in diagnostic and treatment settings. This paper explores control methods and dynamic system modeling in the context of self-propelled remote-controlled capsule endoscopes with a two-mass arrangement. The literature search, conducted at Queen Mary University of London Library from 2000 to 2022, utilized a systematic approach starting with the broad keyword 'Capsule Endoscope' and progressively narrowing down to specific aspects such as 'Capsule Endoscope Control' and 'Self-propelled Capsule Endoscope' using various criteria. Efficiently driving and controlling remote-controlled capsule endoscopes have the potential to overcome the current limitations in medical technology, offering a viable solution for diagnosing and treating gastrointestinal diseases. Successful control of the remote-controlled capsule endoscope, as demonstrated in this review paper, will lead to a step change in medical engineering, establishing the remote-controlled capsule endoscope as a swift standard in the field. [ABSTRACT FROM AUTHOR]

This paper introduces, as a proof of concept, a tool chain for automated control and simulation of a robot team in the domain of production of carbon-fiber-reinforced polymers. The starting point is a CAD construction of a simple aviation component from which single cut pieces of carbon fiber, together withtheir properties, are extracted. Using this information and the layout of a given robot cell, various possibilities of assignments of cut pieces to grippers and robots or robot teams are determined. Subsequently, two approaches using an PDDL solver are introduced, with the goal of finding a scheduling for the lay-up process. Finally, the resulting process is simulated using a physics and rendering engine. The main purpose of this paper is to show the feasibility of such an approach; we do not concentrate on the optimization of single process steps and other details. Due to the modular structure of our approach, extensions and optimizations of the single blocks are easy to integrate. At the moment, digitization and automated control are little explored areas in the domain of production technology using pick and place processes in the aerospace industry. We think that our work will lead to further research in this direction. [ABSTRACT FROM AUTHOR]

The automotive industry faces challenges in maintaining quality control while at the same time reducing costs and improving efficiency. Outsourcing has emerged as a potential solution. Such an approach can create issues such as communication barriers, quality control problems, and limited visibility into the manufacturing process. This study proposes a cloud-based quality reporting solution to overcome these challenges by providing real-time data analytics, facilitating proper communication, and enabling visibility into quality control processes. This solution significantly reduces waiting times for information regarding product quality status and allows interested parties to access data immediately. The outsourcing company, product producer and customer receive flexible, traceable, mobile cloud-based analytics in real-time. Challenges of this solution are the need to secure data, manage access and ensure the appropriate quality of data by persons performing control. The paper provides practical recommendations for implementing cloud-based quality reporting systems. [ABSTRACT FROM AUTHOR]

This paper presents control design and implementation for a power-assisted mobile trainer that employs neuro-developmental treatment (NDT) principles. NDT is a gait rehabilitation technique for stroke patients that provides minimum intervention at critical gait events. Traditional NDT rehabilitation is an effective post-stroke treatment but is also time consuming and labor intensive for therapists. Therefore, we designed a mobile NDT trainer to automatically repeat therapists' intervention patterns, allowing patients to receive sufficient training without increasing therapists' workloads. Because the trainer was self-propelled, it could cause burdens to stroke patients with limited muscle strength, thereby potentially degrading the rehabilitation effects. Hence, this paper proposes a power-assisted device that can let the mobile trainer follow the user, allowing the subject to focus on the rehabilitation training. We conducted system identification and control design for the power-assisted NDT trainer. We then implemented the designed controllers and tested the trainer. Finally, we invited 10 healthy subjects and 12 stroke patients to conduct clinical experiments. After using the power-assisted NDT trainer, most participants exhibited improvements in swing-phase symmetry, pelvic rotation, and walking speed. Based on the results, the power-assisted device was deemed effective in facilitating stroke rehabilitation. [ABSTRACT FROM AUTHOR]

Complex robotic systems, such as humanoid robot hands, soft robots, and walking robots, pose a challenging control problem due to their high dimensionality and heavy non-linearities. Conventional model-based feedback controllers demonstrate robustness and stability but struggle to cope with the escalating system design and tuning complexity accompanying larger dimensions. In contrast, data-driven methods such as artificial neural networks excel at representing high-dimensional data but lack robustness, generalization, and real-time adaptiveness. In response to these challenges, researchers are directing their focus to biological paradigms, drawing inspiration from the remarkable control capabilities inherent in the human body. This has motivated the exploration of new control methods aimed at closely emulating the motor functions of the brain given the current insights in neuroscience. Recent investigation into these Brain-Inspired control techniques have yielded promising results, notably in tasks involving trajectory tracking and robot locomotion. This paper presents a comprehensive review of the foremost trends in biomimetic brain-inspired controlmethods to tackle the intricacies associated with controlling complex robotic systems. [ABSTRACT FROM AUTHOR]

The problem of calculating points and magnitudes of discontinuities in the controls acting on a system described by a nonlinear vector ordinary differential equation is considered. A similar problem is well known in systems theory and belongs to the class of failure identification problems. This paper specifies a regularizing algorithm that solves the problem synchronously with the process of functioning of the control system. The algorithm is based on a feedback control method called the dynamic regularization method in the literature; this method was previously actively used in problems of online reconstruction of nonsmooth unknown disturbances. The algorithm described in this work is stable to information noises and computational errors. [ABSTRACT FROM AUTHOR]

A traditional object of study in the mathematical theory of optimal control is a controlled object with geometric constraints on the control vector 푢 . At the same time, it turns out that sometimes it is more convenient to impose integral constraints on the control vector 푢 . For example, in the theory of automatic design of optimal controllers, it is sometimes assumed that the control vector 푢 is not subject to any geometric constraints, but there is a requirement that the control 푢 푡 and its squared length superscript 푢 푡 2 are Lebesgue summable on the corresponding interval. This circumstance, as well as the fact that the performance index has the form of a quadratic functional, makes it possible to construct an optimal control under rather broad assumptions. Quadratic integral constraints on controls can be interpreted as some energy constraints. Controlled objects under integral constraints on the controls are given quite a lot of attention in the mathematical literature on control theory. We mention the works of N.N. Krasovskii, E.B. Lee, L. Markus, A.B. Kurzhanskii, M.I. Gusev, I.V. Zykov, and their students. The paper studies a linear time-optimal problem, in which the terminal set is the origin, under an integral constraint on the control. Sufficient conditions are obtained under which the optimal time as a function of the initial state subscript 푥 0 is continuous. [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]

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]

Public transport service reliability is crucial for all stakeholders, including users, operators, and society. Bus bunching, where two or more buses on the same route travel closely together, significantly undermines service reliability. This paper reviews bus bunching, its causes and consequences, and control strategies from demand, supply, and decision-making perspectives. It identifies gaps in the literature, emphasising the need for realistic evaluations of control methods and real-world applications. The paper reveals that most bunching solutions prioritise operators over public transport users, and the trade-offs posed by these methods require further examinations. Hybrid methods combining holding with other measures have outperformed standalone holding methods but need real-world testing. User-centric approaches, such as encouraging and incentivising passengers to choose less crowded vehicles or wait, have demonstrated some potential in alleviating service bunching. However, their effectiveness in real-world applications present important research directions. In summary, the practical classification and framework presented in this review can assist policymakers in making informed and optimised decisions by considering various variables and performance measures involved in the process, and in finding balanced solutions for passenger and operator. [ABSTRACT FROM AUTHOR]

This paper explores how digital tracking is incorporated into family life in Munich. Parents using tracking technologies found them to be useful in caring for their children’s safety and preventing violence. This paper argues that monitoring was characterised by moral friction, since parents wanted their children to be more independent and questioned whether they should control their everyday movements and online activities, but were anxious about what could happen if they did not track their children digitally. The paper reports qualitative research involving both interviews (21 with parents and 8 with children) and participant observation in home settings or community organisations. The paper also analyses children’s experiences, who found tracking to be useful in emergencies or for locating their parents, but mostly used social media sites such as Snapchat to monitor their friends or siblings. The paper discusses horizontal forms of surveillance in which children would check their parent’s or friend’s locations in real time. As such, we see multiple ways through which notions of familial care are negotiated in relation to the use of digital tracking. [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]

This paper is a critique of the current version of Derk Pereboom's "disappearing agent argument" against event-causal libertarianism. Special attention is paid to a notion that does a lot of work in his argument—that of settling which decision occurs (of the various decisions it is open to the agent to make at the time). It is argued that Pereboom's disappearing agent argument fails to show that event-causal libertarians lack the resources to accommodate agents' having freedom-level control over what they decide. The connection between the disappearing agent argument and the problem of present luck is explored, as is the connection between settling which decision one makes and luck. Pereboom's disappearing agent argument also is distinguished from another argument with the same name that targets intentional action itself. [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]

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]

In this study, an online monitoring system was implemented for the operational control of an industrial-scale steam generation system. The proposed system allows the migration from measuring boiler efficiency under stationary conditions to measuring it under seasonal conditions, providing greater opportunities for improvement in energy performance. For this purpose, a baseline and goal line model of energy consumption as a function of steam production for an operational base period was constructed. The study shows that the steam generation process has a consumption rate of 0.0885 m³/kg, which is associated with boiler technology, fuel quality, insulation condition, heat recovery equipment, among others. In addition, there is evidence of non-production consumption of 41.225 m³/h, which is mainly due to average consumption in non-productive maneuvers such as starting, stopping, and searching for an operating regime in response to changes in steam demand. The correlation between gas consumption and steam generation was 86.4 %, which represents a 13.6 % variability of consumption associated with controllable operational variables with opportunity for adjustment. The monitoring and control of the main operating parameters of the boiler allows an economic savings of 3.13 % in the boiler, which implies a reduction in operating costs of 92,843 USD per year. The analysis of the operational parameters indicates that it is necessary to maintain a feed water temperature higher than 65 °C and a flue gas temperature lower than 214 °C to ensure boiler efficiency higher than 80 %. With the implementation of activities focused on reducing the combustion gas temperature, increasing the feed water temperature, and controlling operational variables, a 9.01 % reduction in the boiler's natural gas consumption was achieved because of the implementation of operational control. [ABSTRACT FROM AUTHOR]

This paper is mainly focused on the solution of Sylvester matrix differential equations with time-independent coefficients. We propose a new approach based on the construction of a particular constant solution which allows to construct an approximate solution of the differential equation from that of the corresponding algebraic equation. Moreover, when the matrix coefficients of the differential equation are large, we combine the constant solution approach with Krylov subspace methods for obtaining an approximate solution of the Sylvester algebraic equation, and thus form an approximate solution of the large-scale Sylvester matrix differential equation. We establish some theoretical results including error estimates and convergence as well as relations between the residuals of the differential and its corresponding algebraic Sylvester matrix equation. We also give explicit benchmark formulas for the solution of the differential equation. To illustrate the efficiency of the proposed approach, we perform numerous numerical tests and make various comparisons with other methods for solving Sylvester matrix differential equations. [ABSTRACT FROM AUTHOR]

Oats are more competitive with weeds than most other crops, especially when both the seed rate, due to its high twinning capacity, and the sowing season that will provide the oat crop with the vigor it needs to compete against weeds, through a good growth of roots and foliage, which will be reflected in their shading. With all these advantages, weed control is an essential and timely factor in obtaining a high production and quality of oats. The purpose of the present work was to determine the reserve of weed seeds in the soil, since their number and germinating ability make the soil the main source of weeding of agricultural crops, namely oats; the structure of soil weeding was also determined and the positive effect of applying the herbicide Granstar® Super (25% thifensulfuron-methyl + 25% tribenuron-methyl) against annual and perennial dicotyledonous weeds at a dose of 40 g/ha post-emergence was observed. The research was carried out on the Ovidiu variety, during the vegetation period of 2021 in Mircea Vodă commune, Brăila county. The degree of weeding in the oat variety Ovidiu decreased, as a result of the application of the Granstar® Super herbicide, from 147.2 weeds/m2 to 6.1 weeds/m2. The application of the Granstar® Super herbicide led to a very significant increase in production in the case of the Ovidiu oat variety, of 380 kg/ha. [ABSTRACT FROM AUTHOR]

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This paper illustrates an experimental activity for the closed-loop position control of an actuator made using shape memory alloy (SMA) wire. A solution with the self-sensing effect was implemented to miniaturize the systems, i.e., without external sensors. A proportional control algorithm was initially used, demonstrating the idea's feasibility; the wire can behave simultaneously as an actuator and sensor. An experimental investigation was subsequently conducted for the optimization of the developed actuator. As for the material, a Flexinol wire, Ni-Ti alloy, with a diameter of 0.150 mm and a length of 200 mm, was used. Preliminarily, characterization of the SMA wire at constant and variable loads was carried out; the characteristics detected were elongation vs. electric current and elongation vs. electrical resistance. The control system is PC based with a data acquisition card (DAQ). A drive board was designed and built to read the wire's electrical resistance and power it by pulse width modulation (PWM). A notable result is that the actuator works with good precision and in dynamic conditions, even when it is called to support a load up to 65% different from that for which the electrical resistance–length correlation has previously been experimentally obtained, on which the control is based. This opens up the possibility of using the actuator in a counteracting configuration with a spring, which makes hardware implementation and control management simple. [ABSTRACT FROM AUTHOR]

Traditional robot control theory assumes implicitly that robot manipulators are equipped with ideal torque actuators (i.e., torque-driven robots). However, it is important to note that both industrial robots and economical didactic ones do not typically feature such torque actuators. In contrast, many robotics laboratories engaged in academic and research activities employ robots equipped with position servo actuators, which do not support torque control input commands. This paper aims to bridge the gap between theory and practical implementation of robot control from an automatic control perspective. To achieve this goal, a new method is introduced for converting any torque requesting control system, designed for torque–driven robots, to be directly applied to robots using proportional embedded control with position servo actuators (servo–actuated robots lack direct torque input for control). The method relies on the inverse dynamics approach, considering the comprehensive nonlinear model of a position servo–actuated robot structure. This model encompasses servos dynamics, inheriting both the advantages and disadvantages associated with model–based control algorithms. [ABSTRACT FROM AUTHOR]

Prior research investigating situations involving one trustor and multiple trustees often examines how a trustor's trust in one party affects their amount of trust in another party. This paper fills a gap by predicting the effects of trust. The Perceived Influence (PI) Model of Trust is an individual-level model focused on the perceptions of a trustor. It builds upon the Mayer et al. (1995) model by integrating insights from literature on task interdependence and expanding to two trustees. The PI model describes and explains three possibilities for how a trustor's trust in two trustees may combine to form a sense of aggregate multi-trustee trust via: (1) additive effects, such that the trustor's trust in each of the trustees has independent effects on the aggregate; (2) compulsory effects, such that increasing the amount of trust in one trustee increases the effect of trust in the other trustee; and (3) compensatory effects, such that increasing trust in one trustee decreases the effect of trust in the other trustee. We propose that the theoretical mechanism explaining which of these three possibilities takes place is the trustor's perceived influence of the trustees, which is tightly linked to perceptions of task requirements necessary to attenuate the trustor's risk. The PI model begins to fill an important gap in the literature pertaining to pervasive, but rarely considered, multi-trustee situations, and proposes the importance of trustor perceptions of trustee influence and task requirements for future models of trust. [ABSTRACT FROM AUTHOR]

Background: Because cities prioritize economic development and face ecological space and resource constraints, the development of rural areas, which have untapped potential, should receive increased attention. Consequently, rural ecological landscapes should be constructed through the control of land use types and quality to fully ensure the sustainable development of urban and rural ecosystems. The digital twin is a philosophy and a methodology that connects the digital and physical realms, facilitating realistic and dynamic mapping simulations of the real world. This capability offers valuable insights for digital decision-making, maintenance, and optimization of rural ecological landscapes. Given the digital transformation of rural ecological landscape control, this paper proposes a rural intelligent control approach based on the digital twin concept and new technology. Methods: Five components of the rural ecological landscape digital twin framework are selected to collectively facilitate the monitoring and analysis of rural conditions, formulate strategic solutions, implement management and control behaviors, and enhance participant interaction. The method includes three steps: mapping and fusing information, constructing and managing a database, and constructing a digital platform. Data mining and spatial fusion are performed through targeted mapping methods, and Oracle and ArcGIS SDE are utilized for database construction and fused data management. The twin platform is generated via HTML, desktop application development and geographic information system development technologies using a distributed system as the core. Results: Based on multiple case studies, our platform efficiently gathers system information on rural ecological landscapes using a twin model. Through evaluation and analysis, it determines landscape governance zones, adjusting them based on land use conditions. The platform refines control schemes with feedback from diverse users, ensuring effective control in various scenarios. Its key advantages include high development efficiency, flexible access, and smooth cross-platform integration. Although implemented in rural China, the proposed digital twin framework is applicable to any rural area requiring ecological landscape digital control. Conclusions: The value of the platform lies in its powerful information processing capability, overcoming the limitations of time and space and enabling the presentation and integration of fictional scenes Thus, the platform provides a reference for the digital transformation of rural ecological landscape control. [ABSTRACT FROM AUTHOR]

This paper enhances the agent model of ordinary individuals by incorporating the roles of places in the transmission, prevention, and control in the process, establishing a fundamental connection between these two types of agents through individual travel rules. The impact of real-world prevention and control measures on regional epidemic transmission is studied based on this model. Firstly, based on the analysis of place elements in typical cases of major infectious diseases, we give the classification of places. Secondly, the resident agent and the place agent are constructed and rules are established to form an agent-based major infectious disease transmission model considering the place. Then, the simulation process is established and an ideal regional environment is constructed to simulate overall changes in major infectious disease scale and spread speed. Additionally, evolutionary simulations are conducted for individual isolation intensity and place control time during emergency management stages to compare infection outcomes, and we analyze different roles and application scenarios of specific prevention and control measures. Finally, simulation results from real major infectious disease cases in Yangzhou, China, validate the effectiveness of this model in predicting major infectious disease development trends as well as evaluating prevention and control measure effects. [ABSTRACT FROM AUTHOR]

This review paper aimed to draw the red line passing through almost 25 years of research on waterjet cutting carried out at WJ_Lab, the waterjet laboratory of the Department of Mechanical Engineering of Politecnico di Milano. The purpose was not to just historically analyse the obtained scientific results by themselves but to make them even more useful by introducing the concept of the waterjet digital twin passing through the accuracy improvements due to microAWJ. This strategy effectively creates synergy among the topics and gives the opportunity to researchers in this field to both have an example of how research in industrial manufacturing processes can be guided by scientific and industrial needs, at least from the author's point of view, and to appreciate how it can be made useful for further improvements by introducing a powerful concept as the digital twin. [ABSTRACT FROM AUTHOR]

The global environmental issue of soil contamination with antibiotic-resistance genes has garnered increased attention in recent years due to its impact on ecosystems and human health. Despite this recognition, researchers face challenges in comprehensively understanding the mechanisms underlying the production and dissemination of soil resistance genes, particularly in relation to their implications for human health. This lack of understanding poses a barrier to the development of effective and precise control strategies. Biochar, a sustainable material, exhibits favorable adsorption properties characterized by its large pores and specific surface area. Therefore, we propose to explore the potential application of biochar addition in soil resistance gene management. In order to establish a solid research foundation in this area, in this paper we review the mechanisms underlying the generation and accumulation of soil resistance genes over the last decade, along with their transmission pathways and interfacial interactions. Biochar may help repair soil resistance genes by affecting factors like antibiotic levels, environmental conditions, enzymatic activity, and gene migration mechanisms, opening up new research possibilities. Highlights: The sources, transmission routes and effects on human health of soil ARGs are summarized, and the mechanism of soil ARGs control by biochar is discussed on the basis of the positive effects by biochar. The ways in which biochar affects soil ARGs are analyzed in several directions (soil physicochemical properties, heavy metal content, antibiotic content, microbial structure and enzyme activity) in an attempt to provide a basis for the next studies. The mechanisms of biochar in the regulation of antibiotics and heavy metals for soil ARGs removal are systematically and comprehensively described, while also prospecting the potential application of biochar in soil ARGs removal. [ABSTRACT FROM AUTHOR]

Women' s health-related human rights are contested. Beyond the recent pushbacks on abortion rights, more subtle developments are discernable. This paper dissects one case study illustrating how professional self-regulation in pharmaceutical law can undermine equal access to emergency contraception (EC). In Switzerland, around 100,000 "morning after" pills are sold through pharmacies per year. Empirical evidence demonstrates how traumatic or shameful the experience can be for women. Because if regulation was liberalized in 2002 and EC has since been available without a doctor' s prescription, access remains subject to strict professional gatekeeping. Women must undergo a compulsory interview with a pharmacist in a pharmacy backroom. They must indicate their contact details, answer an intrusive questionnaire archived for twenty years, receive information about sexually transmitted diseases, and bear the costs. Prices for EC vary and peak in the evening and on weekends. The exceptionalism of access to EC, despite formal legal liberalization, highlights gender bias and perpetuates shame and stigma surrounding women's sexually active behavior. Switzerland's normative position on access to contraception is based on individual responsibility and formal equality. Every woman is responsible for avoiding unwanted pregnancy, and access to EC is guaranteed since it is available in all pharmacies. In reality, access obstacles created by EC dispensing mechanisms result in intersectional inequalities, depending on women's age, socio-economic background, and migration status. This paper critically deconstructs the intricate intertwining of a liberal focus on individual responsibility and the disciplining power mechanisms of professional gatekeepers affecting female bodies and choices. Going beyond the personal and the political, it demonstrates how backsliding on sexual and reproductive rights can happen through the backdoor of professional self-regulation. Finally, this paper focuses on a substantive concept of equality for realizing women's health-related human rights. [ABSTRACT FROM AUTHOR]