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Controlling the connectivity and rigidity of kirigami, i.e. the process of cutting paper to deploy it into an articulated system, is critical in the manifestations of kirigami in art, science and technology, as it provides the resulting metamaterial with a range of mechanical and geometric properties. Here, we combine deterministic and stochastic approaches for the control of rigidity in kirigami using the power of k choices, an approach borrowed from the statistical mechanics of explosive percolation transitions. We show that several methods for rigidifying a kirigami system by incrementally changing either the connectivity or the rigidity of individual components allow us to control the nature of the explosive transition by a choice of selection rules. Our results suggest simple lessons for the design of mechanical metamaterials. [ABSTRACT FROM AUTHOR]

Due to the huge amounts of wastewater discharge and the high pollution loads in papermaking industry, many greenhouse gases (GHG) are emitted in the papermaking wastewater treatment process. The wastewater dissolved oxygen (DO) control has been considered as the most cost-effective control solution for GHG reduction in wastewater treatment plants (WWTP). However, the competition between contaminant removal efficiency and GHG reduction hinders the drastic reduction of GHG emissions from WWTP. In this study, based on the established integrated GHG emission model, explicitly considering the total GHG reduction targets on the premise of effluent compliance, an intelligent control scheme has been developed for an activated sludge process in a paper mill. Regarding DO as the controlled variable, the proposed hierarchical optimal proportional-integral (HOPI) control scheme was established consisting of three layers: 1) Layer 1 for the effluent quality estimation, 2) Layer 2 for the optimal DO set point determined by genetic algorithm with the influent variations to obey discharging norms and reduce GHG emissions, 3) Layer 3 for the DO tracking proportional integral (PI) control with the controller parameters adjusted by the back propagation neural network to track the dynamically optimized DO set points. The simulation results showed that, compared with the open-loop (OL) operation (averaged aeration, 10/h), the proposed HOPI control (averaged aeration, 7.9/h) reduced the GHG emissions by 12.54% under the premise of discharging norms, which was mainly attributed to the reduction of the aeration electricity consumption. In contrast, the PI control (averaged aeration, 12.9/h) increased the GHG emissions by 7.48% compared with the OL operation. Thus, the proposed HOPI control strategy has demonstrated potential for the application of GHG reduction in industrial WWTPs. [ABSTRACT FROM AUTHOR]

The burgeoning digital-platforms literature across multiple business disciplines has primarily characterized the platform as a market or network. Although the organizing role of platform owners is well recognized, the literature lacks a coherent approach to understanding organizational governance in the platform context. Drawing on classic organizational governance theories, this paper views digital platforms as a distinct organizational form where the mechanisms of incentive and control routinely take center stage. We systematically review research on digital platforms, categorize specific governance mechanisms related to incentive and control, and map a multitude of idiosyncratic design features studied in prior research onto these mechanisms. We further develop an integrative framework to synthesize the review and to offer novel insights into the interrelations among three building blocks: value, governance, and design. Using this framework as a guide, we discuss specific directions for future research and offer a number of illustrative questions to help advance our knowledge about digital platforms' governance mechanisms and design features. [ABSTRACT FROM AUTHOR]

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]

In 1991 we began to model interactions between formal and relational incentive contracts. We saw this work as agency theory. By the time the paper was published (BGM, 1994), we had begun to view the research agenda more broadly – with connections to organizational culture, the theory of firms’ boundaries, and more. Eventually, we built from this initial work, analyzing delegation within organizations as necessarily informal and moving beyond relational agency to structuring relationships (where parties choose their formal governance structure to facilitate their relational contract). In this essay we sketch theoretical, empirical, and methodological lessons we learned during this twenty-year journey [ABSTRACT FROM AUTHOR]

Of all mine disasters, fires are very threatening to mine safety and often lead to the most serious consequences. Research on mine fire prevention technology and theory has experienced significant growth and is attracting escalating academic interest and attention. However, dedicated literature reviews on this topic are scarce. For the purpose of uncovering the research characteristics and trends on mine fire prevention technology and theory, this paper employs bibliometric analysis using the Web of Science Core Collection database. This study presents a detailed analysis of relevant articles published between 2010 and 2022. An assessment of the influences of journals, countries, institutions, and authors was conducted through a citation analysis. Furthermore, this paper describes co-authorship networks among different countries, institutions, and authors. Lastly, a review of the mine fire prevention techniques and theories researched during this period was carried out through a keyword clustering analysis. Four main research topics in mine fire prevention research were identified: "mine fire control technology", "mine fire occurrence mechanism", "mine fire prediction technology", and "mine fire monitoring technology". Additionally, the theory study of spontaneous combustion and its underlying mechanisms may represent a potential focus for future research. These findings contribute to providing a solid foundation for future research endeavors in this field of fire prevention. [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]

Electroencephalogram (EEG)-based brain–computer interfaces (BCIs) provide a novel approach for controlling external devices. BCI technologies can be important enabling technologies for people with severe mobility impairment. Endogenous paradigms, which depend on user-generated commands and do not need external stimuli, can provide intuitive control of external devices. This paper discusses BCIs to control various physical devices such as exoskeletons, wheelchairs, mobile robots, and robotic arms. These technologies must be able to navigate complex environments or execute fine motor movements. Brain control of these devices presents an intricate research problem that merges signal processing and classification techniques with control theory. In particular, obtaining strong classification performance for endogenous BCIs is challenging, and EEG decoder output signals can be unstable. These issues present myriad research questions that are discussed in this review paper. This review covers papers published until the end of 2021 that presented BCI-controlled dynamic devices. It discusses the devices controlled, EEG paradigms, shared control, stabilization of the EEG signal, traditional machine learning and deep learning techniques, and user experience. The paper concludes with a discussion of open questions and avenues for future work. [ABSTRACT FROM AUTHOR]

The paper presents the design and development of a brain-controlled wheel chair. This is a real time model of a low-cost wheel chair based on the Brain Control Signal by Eye Blink, for the persons disabled with quadriplegia. This model expected to benefit the poor paralyzed people as it provides a simplified low-cost model of the wheel chair. The model is realized through data comparison in serial communication with the special purpose microcontroller IC. This is detected like an object cross in a transmitter and receiver, and it will intimate. In this paper voice is our object detected by using infrared signal serially interact with controller, which in turn, controls the wheel chair movements based on brain wave signal. The work presented in this paper is the mini-project work of the under-graduate students of the engineering college guided by their supervisors. [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 aims to educate airport operators in how to be better prepared for an active threat incident. The paper does not discuss preventative measures but focuses on lessons learned from a real-life incident that took place in 2017. Information included is derived from a detailed after-action report that focuses on mitigating strategies, communication methods, employee training, and business resumption. [ABSTRACT FROM AUTHOR]