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This article investigates anti‐attack stabilization with passivity problem of uncertain singular semi‐Markov jump systems (singular S‐MJSs) with exogenous disturbance and delay. An ingenious non‐fragile observer‐based neural sliding mode control (SMC) scheme is put forward to solve the problem. First, considering unmeasured states, a distinctive non‐fragile and decoupled observer, which does not contain the control input or any auxiliary sliding mode compensator design as in existing observer‐based SMC approaches, is established such that the disadvantages of sliding mode switching in observers in existing literature can be avoided. Then, "only one sliding surface" design and a new system analysis route are presented, and the derived sliding surface is accessibly designed. Next, a new version of stochastic admissibility and passivity sufficient condition is given, and a related algorithm via an optimization problem is proposed to determine the controller gain and the observer gain by linear matrix inequalities (LMIs). Further, a novel observer‐based anti‐attack neural SMC law, which utilizes a neural network‐based approach to approximate actuator attack, is proposed to stabilize the singular S‐MJSs against actuator attack. Finally, simulation and comparison results are presented, which demonstrate the effectiveness and superiority of our method. [ABSTRACT FROM AUTHOR]

This paper discusses the issue of passivity analysis of the neutral‐type Cohen–Grossberg neural networks (NTCGNNs) with distributed, transmission, and neutral time‐varying delays. A new method based on the system solutions was proposed to analyze passivity. It is important to note that this paper focuses solely on introducing the proposed method and does not provide a comprehensive analysis of NTCGNNs. This method does not require for the construction of Lyapunov–Krasovskii functional (LKF) or model transformation, thus reducing computational effort and complexity. By using this new way and the inequality technique, a passivity criterion for NTCGNNs with multiple time‐varying delays is derived. The applicability of the derived criterion was demonstrated through a numerical example. [ABSTRACT FROM AUTHOR]

ABSTRACT This paper analyzes the stability of a grid‐following inverter by the complex vector control in αβ domain and by the PLL synchronization control in dq domain. It is known that the frequency transfer function of the PLL may affect mutual interactions between grid and line impedances. This paper analyzes the frequency characteristics of the inverter based on the mixed‐domain control for stability by the impedance method. Considering frequency coupling effects by the PLL control, it is found that the passivity of the inverter is violated and it may become unstable for a weak grid. This result is validated by analytical derivation, simulation, and experiment. [ABSTRACT FROM AUTHOR]

Resistance is often depicted as events that are active, adversarial and antagonistic. However, we would like to suggest that it could also be understood through other narratives, which connect political pursuits to passivity rather than activity. These stories can contribute to increasing our awareness of the limits of the resistance scholarship and extend the view of political performances. In this paper, two different trajectories of counter-conduct – the anti-sexual assault movement in Japan, and the anti-authoritarian struggles in Cambodia – will be used to reveal how resistance is sometimes delegated or outsourced, rather than actively pursued by the subject. In these cases, the political subjects' passivity feeds political activities, but, on the other side of the coin, the activities also foster passivity. [ABSTRACT FROM AUTHOR]

Cr2O3 films and coatings have widespread applications in the surface engineering of key industrial materials like irons and steels. The reason is that it can easily form and effectively prevent corrosion of metallic matrix in a lot of natural environments. However, the nature of the coating strongly depends on its formation conditions, which have a great influence on its protectiveness, and the relationship between the passivity of Cr2O3 and its integrity, uniformity, and stability is still rarely understood. In this work, three different oxidation methods are employed to prepare chromium oxide. The effects of each oxidation method on the surface structure, phase component, and electrochemical performance are comprehensively investigated. The results show that the main component of different films is Cr2O3, and oxide films prepared in a water plasma environment have relatively higher compact structure, fewer defects, and more positive corrosion-resistant potential, suggesting that lower oxidative partial pressure of film growth condition would be beneficial to obtain better passive performance. [ABSTRACT FROM AUTHOR]

Even if a water distribution system (WDN) is well designed, it must be safely operated over a wide range of constraints and requirements. Traditionally, rudimentary control strategies have been employed, such as simple level or pressure control, although sophisticated control strategies have developed in other applications. We illustrate here some of the modern control possibilities by designing controllers for two challenging scenarios in a WDN: a pumping system which suddenly loses power, and safely filling an initially empty pipe using a pump. Check valve behaviour is significant in both scenarios. We show that with a minor modification, a commonly used empirical, nonlinear model of a check valve is port-Hamiltonian (pH). The benefits of being pH include interconnection with pH models of WDNs, straightforward stability analysis, and simple tools for controller design. We use this property to motivate WDN controllers that are able to meet these two specific control requirements. [ABSTRACT FROM AUTHOR]

The control of medium-voltage cascaded H-bridge (CHB) converters demands precise, high-bandwidth, low-latency, and isolated measurements. Traditional analog-to-digital converters (ADCs) can facilitate multisampling methods to meet these requirements but do not provide the high-voltage galvanic isolation that may be necessary in a system operating at medium voltage. Sigma-Delta ADCs (SD-ADCs) present a promising alternative due to their superior noise rejection capabilities and direct integration with the optical fiber interface. However, the inherent latency associated with SD-ADCs, stemming from their operating principles, poses challenges when integrating them with multisampling methods. This paper analyzes the integration of multisampling techniques with SD-ADCs for medium-voltage CHB converter control. First, the impact of SD-ADC-induced delays on the control system is elucidated from the passivity perspective. Second, the practical implementation of multisampling with SD-ADCs is discussed in detail. Finally, experimental results from a 2400 Vrms medium-voltage CHB converter are presented to validate the analysis and illustrate the effectiveness of the proposed implementation. [ABSTRACT FROM AUTHOR]

This paper presents a robust control strategy for trajectory-tracking control of Skid-Steer Mobile Manipulators (SSMMs) using a Robust Nonlinear Model Predictive Control (R-NMPC) approach that minimises trajectory-tracking errors while overcoming model uncertainties and terra-mechanical disturbances. The proposed strategy is aimed at counteracting the effects of disturbances caused by the slip phenomena through the wheel–terrain contact and bidirectional interactions propagated by mechanical coupling between the SSMM base and arm. These interactions are modelled using a coupled nonlinear dynamic framework that integrates bounded uncertainties for the mobile base and arm joints. The model is developed based on principles of full-body energy balance and link torques. Then, a centralized control architecture integrates a nominal NMPC (disturbance-free) and ancillary controller based on Active Disturbance-Rejection Control (ADRC) to strengthen control robustness, operating the full system dynamics as a single robotic body. While the NMPC strategy is responsible for the trajectory-tracking control task, the ADRC leverages an Extended State Observer (ESO) to quantify the impact of external disturbances. Then, the ADRC is devoted to compensating for external disturbances and uncertainties stemming from the model mismatch between the nominal representation and the actual system response. Simulation and field experiments conducted on an assembled Pioneer 3P-AT base and Katana 6M180 robotic arm under terrain constraints demonstrate the effectiveness of the proposed method. Compared to non-robust controllers, the R-NMPC approach significantly reduced trajectory-tracking errors by 79.5% for mobile bases and 42.3% for robot arms. These results highlight the potential to enhance robust performance and resource efficiency in complex navigation conditions. [ABSTRACT FROM AUTHOR]

This article develops a cultural and contextual approach to studying agency that attends to variation in how people narrate their experiences. Drawing on the large-scale, nationally representative American Voices Project data, the article uses computational methods to test patterns in agentic expression and qualitative methods to examine how respondents narrate agency and passivity as they describe their lives. This analysis captures agentic moments, widespread narratives through which people emphasize their agentic selfhood as they recount specific situations. Moreover, individuals use narrative moves—such as shifting their focus and drawing on subtypes of agency—to craft agentic moments despite constraints. We argue that narratives of agency are variable, situational, and often co-occurring with narrative passivity, which enables people to narrate themselves as agentic even in challenging situations.

Reciprocity of linear input-output systems is defined as symmetry of its impulse response or transfer matrix. In the famous 1972 paper by Willems [Dissipative dynamical systems, part II: Linear systems with quadratic supply rates, Arch. Ration. Mech. Anal., 45, pp. 352--393] it was shown how reciprocity can be reflected in the state space realization. Furthermore, it was shown how to combine reciprocity with passivity in order to obtain state space realizations with physically motivated properties, including relaxation systems. The current paper is concerned with the extension of this theory to the nonlinear case. Emphasis is on nonlinear reciprocal systems with a Hessian pseudo-Riemannian metric. The combination of reciprocity with passivity is elucidated from a port-Hamiltonian perspective. [ABSTRACT FROM AUTHOR]

We consider a class of infinite dimensional (distributed) dissipative port-Hamiltonian systems whose dynamics is generated by a block operator in a Hilbert space that has a bounded dissipative diagonal and a possibly unbounded skew-adjoint off-diagonal. Sufficient conditions for the strong and exponential stability of the underlying semigroup generators are provided along with the derivation of a power-balance equation for classical solutions of the associated boundary control system. Furthermore, we consider interconnections of several such distributed pH systems and show that Kirchhoff-type interconnections preserve the underlying structure of the considered block operators. The results are illustrated for a power network connecting several prosumers via distributed transmission lines that are modeled based on the telegraph equations. [ABSTRACT FROM AUTHOR]

The current study investigates the influence of immersion time (7, 14, 21, and 28 days) on the corrosion behaviour of American Petroleum Institute (API) X70 and X80 steel grades in freely aerated simulated concrete pore solution (pH ~ 12 to 13.8) utilizing electrochemical techniques such as electrochemical impedance spectroscopy, linear polarization, and cyclic polarization. The electrochemical results suggest that the corrosion resistance of X70 line pipe steel increases as immersion time increases (from 7 to 28 days) due to the formation of a stable protective oxide layer on the surface. In the case of X80 line pipe steel, however, the corrosion resistance increases as immersion time increases from 7 to 14 days due to the preferential dissolution of bainite as a result of its higher activity, which initiates the formation of passive film. Furthermore, after 21 days of immersion of X80 line pipe steel in simulated pore solution, a considerable decline in corrosion resistance was observed, which indicates de-passivation, as a result of an increase in oxide film thickness and subsequent spalling off. Intriguingly, as compared to X80 line pipe steel, X70 line pipe steel has a greater potential for producing a stable protective oxide layer without the appearance of minor cracks after a 28-day immersion period, thereby preventing further corrosion and enhancing corrosion resistance. [ABSTRACT FROM AUTHOR]

Hope is in a twofold crises in Western societies: perceived as unavailable by some and as undesirable by others. Against this background, this introduction argues that there is a need to ask anew what (if anything) citizens should hope for. After some introductory remarks both about the current role of hope in the public arena and important developments in recent philosophical debates, I provide an overview of the contributions to the Special Issue. Through a variety of theoretical lenses and from a variety of theoretical backgrounds, the contributors systematically ask which hopes (if any) we should cultivate or whether it may sometimes be necessary to let go of certain hopes. While they agree that hope is indispensable as a way of dealing with our fragility and sustaining our resolve, it is not without dangers. What emerges is a profile of hope as a complex and ambivalent attitude that has so far received too little attention by political philosophers, despite its prominent and increasingly contested role in political practice. [ABSTRACT FROM AUTHOR]

This article develops a cultural and contextual approach to studying agency that attends to variation in how people narrate their experiences. Drawing on the large-scale, nationally representative American Voices Project data, the article uses computational methods to test patterns in agentic expression and qualitative methods to examine how respondents narrate agency and passivity as they describe their lives. This analysis captures agentic moments, widespread narratives through which people emphasize their agentic selfhood as they recount specific situations. Moreover, individuals use narrative moves--such as shifting their focus and drawing on subtypes of agency--to craft agentic moments despite constraints. We argue that narratives of agency are variable, situational, and often co-occurring with narrative passivity, which enables people to narrate themselves as agentic even in challenging situations. [ABSTRACT FROM AUTHOR]

Purpose: This paper aims to characterize the surface film formed on Alloys 800 and 690 in chloride and thiosulfate-containing solution at 300°C. Design/methodology/approach: Alloy 800 and 690 were immersed in chloride and thiosulfate-containing solution at 300°C up to five days, and then the surface film was analyzed by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM) and energy dispersive X-ray spectrometers (EDX). Findings: Through static immersion experiments in a high-temperature and high-pressure water environment, the alloy samples covered by surface film after five days of immersion were obtained. The morphology of the surface film was characterized at both horizontal and cross-sectional scales using SEM and focused ion beam-TEM techniques. It was observed that due to the influence of the quartz lining, the surface film primarily exhibited a bilayered structure. The first layer contained a significant amount of SiO2, with a higher content of metal hydroxides compared to metal oxides. The second layer was predominantly composed of Fe, Ni and Cr, with a higher content of metal oxides compared to metal hydroxides. Originality/value: The results showed that the materials of the lining of the autoclave could significantly influence the film composition of the tested material, which should be paid attention when analyzing the corrosion mechanism at high temperature. [ABSTRACT FROM AUTHOR]

The present work investigates the effect of microstructure, pH as well as the role of aggressive chloride ions on the corrosion behavior of American Petroleum Institute (API) X70 and X80 steel grades. The corrosion behavior was studied using single-run cyclic polarization in different solutions followed by microstructural analysis of the corroded samples to determine the mode and extent of corrosion damage. The solutions consist of a near-neutral aqueous sodium chloride solution, mildly alkaline carbonate-bicarbonate solution (pH-8.8), and highly alkaline carbonate-bicarbonate solution (pH-12) with and without the presence of chlorides. Ferrite phase in both the steel was found to dissolve preferentially in the different solutions leading to pitting as a result of microgalvanic coupling with the cementite and/or bainite phase. Interestingly, the corrosion resistance of the X70 grade was found to be greater than X80 at near-neutral as well as low alkaline carbonate-bicarbonate solutions, whereas the X80 performed better in higher pH solutions. Such contrasting corrosion behavior is attributed to the compactness, thickness, and electronic resistance of the passive oxide/hydroxide films formed during polarization in both the steel. [ABSTRACT FROM AUTHOR]

This paper presents a disturbance observer‐based controller for a class of multi‐actuator systems that possess passivity properties. By distributing the input and aggregating the output using the same vectors, the original plant is transformed into an aggregation‐and‐distribution plant (ADP), which is also passive. Based on the ADP, this paper derives the conditions for the controller to sufficiently ensure that the overall system has a finite L2‐gain. The conditions can be checked via the passivity notation of several transfer functions. It is not required to establish the overall system's dynamical equation, thereby alleviating the design burden. The additional objective can be attained by performing an optimization on the aggregation/distribution vectors. Several practical applications are introduced as motivating examples, and the effectiveness of the proposed method is demonstrated by the integration of motion control and energy management for electric vehicles. [ABSTRACT FROM AUTHOR]

This paper aims to clarify the evolution of the notion of primary matter in Leibniz’s philosophy. The analysis takes the scholastic discussion on the reality of primary matter as a framework to explain the development of Leibniz’s ideas. It will be shown that Leibniz argued in his earlier writings for a conception of primary matter as some sort of being (similarly in line with some scholastic philosophers like Scoto, Ockam, and Suarez). In contrast, in his mature metaphysics, he deployed this primary matter of reality, approaching Aquinas’s position in a creative and novelty manner.

Summary: LCL‐type grid‐connected inverters have seen extensive use of the passivity‐based control (PBC) system. However, traditional PBC systems rarely take time delay into account while designing the system or doing a stability study. Therefore, utilizing Lyapunov's criterion to conclude that the system is stable is not accurate. The analysis revealed that the differential terms of PBC loops with the Euler–Lagrange (EL) mathematical model could induce instability considered control delay for LCL‐type grid‐connected inverter system. Compared with traditional EL‐PBC method, this paper proposed a reconstructed EL‐PBC scheme by properly optimizing the noise term. Then, the equivalent output impedance of the grid‐connected inverter system with proposed controller is analyzed with frequency domain passivity theory. The controller parameters are also optimized to ensure both the internal stability of LCL‐type grid‐connected inverter and the risk of interactive resonance in complex weak and nonideal grid. Results from simulation and experimentation support the modified control structure's efficacy and performance. [ABSTRACT FROM AUTHOR]

This article examines the stability behavior of Lipschitz nonlinear discrete-time systems employing saturation overflow and external disturbance. The proposed criterion utilizes a very strict passivity-based approach for stability investigation of the interfered discrete-time systems. A novel stability criterion for the externally interfered nonlinear discrete-time system is established using the quadratic Lyapunov function, saturation characteristics, and Lipschitz condition. The derived criterion assures the passivity performance for the given discrete-time system in terms of its storage function. The presented criterion confirms the asymptotic stability in the presence of zero external disturbance and eliminates the overflow oscillations in a discrete-time system. The obtained conditions are represented in linear matrix inequality for easy tractability. The practicality of the proposed work is verified through numerical examples. [ABSTRACT FROM AUTHOR]

Robots with flexible joints are gaining importance in areas such as collaborative robots (cobots), exoskeletons, and prostheses. They are meant to directly interact with humans, and the emphasis in their construction is not on precision but rather on weight reduction and soft interaction with humans. Well-known rigid robot control strategies are not valid in this area, so new control methods have been proposed to deal with the complexity introduced by elasticity. Some of these methods are seldom used and are unknown to most of the academic community. After selecting the methods, we carried out a comprehensive comparative study of algorithms: simple gravity compensation (Sgc), the singular perturbation method (Spm), the passivity-based approach (Pba), backstepping control design (Bcd), and exact gravity cancellation (Egc). We modeled these algorithms using MATLAB and simulated them for different stiffness levels. Furthermore, their practical implementation was analyzed from the perspective of the magnitudes to be measured and the computational costs of their implementation. In conclusion, the Sgc method is a fast and affordable solution if joint stiffness is relatively high. If good performance is necessary, the Pba is the best option. [ABSTRACT FROM AUTHOR]

This paper reports experimental results concerning the corrosion of 316L austenitic stainless steels produced by ball milling and spark plasma sintering in NaCl electrolyte. Specimens with grain sizes ranging from 0.3 µm to 3 µm, without crystallographic texture, were obtained and compared with a cast that is 110 µm in grain size and an annealed reference. The potentiodynamic experiments showed that the reduction in grain size leads to a degradation of the electrochemical passivation behavior. This detrimental effect can be overcome by appropriate passivation in a HNO3 concentrated solution before consolidation. The Mott–Schottky measurements showed that the semiconducting properties of the passive layer do not vary significantly on the grain size, especially the donor density, which is responsible for the chemical passivation breakdown by chloride anions. The total electrical resistance of the layer, measured by impedance spectroscopy is always lower than the one of a cast and annealed 316L, but it slightly increases with a reduction in grain size in the ultrafine grain range. This is followed by a slight increase in the thickness of the oxide layer. The effect of chloride ions is very pronounced in terms of passivation breakdown if the powder is not passivated prior to sintering. This leads to the nucleation and growth of subsurface main pits and the formation of secondary satellite pits, especially for the smallest grain sizes. Passivation of the 316L powder before sintering has been found to be an effective way to prevent this phenomenon. [ABSTRACT FROM AUTHOR]

The passivity‐based boundary control is considered for stochastic Korteweg–de Vries–Burgers (SKdVB) equations. Both the stochastic input strictly passive (SISP) and stochastic output strictly passive (SOSP) are studied. By introducing Lyapunov functionals and Wirtinger's inequality, sufficient criteria are derived to establish SISP and SOSP for SKdVB equations with boundary disturbances. Moreover, when parameter uncertainties arise in SKdVB equations, the robust stochastic passivity is also investigated and sufficient criteria are presented to achieve the robust SISP and SOSP. Two numerical simulations are employed to show the effectiveness and advantages of our theoretical results. [ABSTRACT FROM AUTHOR]

The corrosion behaviour of mild steel (MS) has been investigated at, 25, 35 and 45 °C in different media containing either pure glacial acetic acid (AA) or mixed with different amounts of formic acid (FA). The results of weight loss (WL) experiments yielded the largest value of corrosion rate (CR) in pure glacial AA. The effect of addition of FA to GAA shows contrasting trends—the CR decreases while increasing FA content from 2 to 10%, whereas a slight increase in CR is observed when FA is varied from 10 to 20%. MS corrodes considerably faster in glacial acetic acid (GAA) at each studied temperature (T). It is inhibited by FA containing some water in it. This behaviour has been compared with that obtained earlier by electrochemical method. The decrease in CR may be attributed to the formation of a protective layer due to the presence of water in FA. The increase in T leads to an increase in CR. It is seen that the compositions of solutions and experimental T have a marked influence on the CR. The surfaces of the specimens prior to and after being subjected to corrosion have been analysed by visual inspection and Scanning Electron Microscopy (SEM). Conclusions drawn from the surface study support the results of WL experiments. [ABSTRACT FROM AUTHOR]

This paper presents a robust control strategy for trajectory-tracking control of Skid-Steer Mobile Manipulators (SSMMs) using a Robust Nonlinear Model Predictive Control (R-NMPC) approach that minimises trajectory-tracking errors while overcoming model uncertainties and terra-mechanical disturbances. The proposed strategy is aimed at counteracting the effects of disturbances caused by the slip phenomena through the wheel–terrain contact and bidirectional interactions propagated by mechanical coupling between the SSMM base and arm. These interactions are modelled using a coupled nonlinear dynamic framework that integrates bounded uncertainties for the mobile base and arm joints. The model is developed based on principles of full-body energy balance and link torques. Then, a centralized control architecture integrates a nominal NMPC (disturbance-free) and ancillary controller based on Active Disturbance-Rejection Control (ADRC) to strengthen control robustness, operating the full system dynamics as a single robotic body. While the NMPC strategy is responsible for the trajectory-tracking control task, the ADRC leverages an Extended State Observer (ESO) to quantify the impact of external disturbances. Then, the ADRC is devoted to compensating for external disturbances and uncertainties stemming from the model mismatch between the nominal representation and the actual system response. Simulation and field experiments conducted on an assembled Pioneer 3P-AT base and Katana 6M180 robotic arm under terrain constraints demonstrate the effectiveness of the proposed method. Compared to non-robust controllers, the R-NMPC approach significantly reduced trajectory-tracking errors by 79.5% for mobile bases and 42.3% for robot arms. These results highlight the potential to enhance robust performance and resource efficiency in complex navigation conditions.

We used the theoretical perspective of humiliation to study the cognitive-emotional and behavioural responses of 242 women regarding episodes of sexist psychological abuse they experienced in relationships. First, we measured the degree of abuse experienced. This was followed by the two key cognitive assessments that underlie humiliation (internalization of self-devaluation and injustice), emotion (humiliation, shame, guilt and anger) and participants' levels of passivity and confrontation. The results show that women who reported higher levels of self-devaluation internalization experienced more humiliation, shame and guilt. Conversely, those who did not demonstrate internalized devalued views of themselves showed higher levels of anger. We identified an indirect significant effect between abuse and passivity via humiliation, shame and guilt, and an indirect significant effect between abuse and confrontation via anger. Therefore, it appears that the internalization of self-devaluation is a key variable in understanding the emotional and behavioural responses of women who experience sexist violence. [ABSTRACT FROM AUTHOR]

For as long as philosophers ignore mind-wandering, they will disregard from one-third to one-half of conscious thoughts. Regrettably, mind-wandering is only seldom addressed in phenomenology. The fundamental ambition of this paper is to offer the first systematic phenomenological investigation of mind-wandering that relies on the classical principles of Husserlian phenomenology. The paper begins with a critique of the dominant conceptions of mind-wandering in contemporary psychology and philosophy. Against such a background, the paper develops a new, phenomenologically-grounded conception of mind-wandering. The paper further focuses on the central resources in Husserlian phenomenology, which can be fruitfully employed in the future interdisciplinary research on mind-wandering. Phenomenological reflections on background consciousness, on pre-predicative experience, on passivity and on self-awareness lie at the center of this analysis. The paper concludes with some reflections on the relation between mind-wandering and daydreaming and on the function of mind-wandering in conscious life. [ABSTRACT FROM AUTHOR]

Summary: This paper discusses the global asymptotic stability and strong passivity analysis of fourth‐order nonlinear and time‐varying dynamical systems by utilizing the Lyapunov direct method. The mathematical model of the main system is obtained from a non‐linear and aging RLC circuit that we have designed before. RLC circuits play an excellent role in the stability of modern system theory. Without the concept of storage elements, the construction of Lyapunov or energy functions for nonlinear and time‐varying systems may be difficult. Because of this, although there are many studies on the stability concept, but the subject has not been completed yet. Therefore, this study may present some mathematical technicalities to the Lyapunov stability with physical considerations. The Lyapunov functions obtained from RLC circuits are natural storage functions, and they satisfy the dissipation inequality. The theoretical stability results of the system are also discussed by Lyapunov's linearization method. The relationship between stability and passivity is also given. Meanwhile, we realized that linear system analysis is not a guaranteed way for determining the stability properties of a full system. Finally, the correctness and availability of the proposed approach are verified through simulation results. [ABSTRACT FROM AUTHOR]

In this afterword, I consider the important contributions this special section makes to the study of the relations between immanence, transcendence, and mediation in the study of Islam and religion more generally, and the dialogue it opens up with the anthropology of Christianity. I go on to suggest that one way to reframe transcendence in relation to these articles is as a phenomenon related to human passivity rather than agency. I also consider the issues these authors raise about how the study of ontologies can shape anthropological studies of transcendence and the nature of anthropology as a way of life. [ABSTRACT FROM AUTHOR]

A mixed potential model (MPM) comprising the Point Defect Model (PDM) and the Generalized Butler Volmer Equation (GBVE) was successfully developed to study the passivity of HDSS 2707. The results show that the dominant point defect within the passive film is the Min+, thereby rendering n-type semiconductor behavior of the barrier layer. The anodic current is independent of the film formation potential whereas it increases with increasing temperature and follows the Arrhenius law. The partial cathodic current of hydrogen reaction is affected by the applied voltage. The anodizing constant of the passive film is calculated to be 2.91 nm/V.

In this article, we study a one-human-multiple-robot interaction for human-enabled multi-robot navigation in three dimensions. We employ two fully distributed control architectures designed based on human passivity and human passivity shortage. The first half of this article focuses on human modeling and analysis for the passivity-based control architecture through human operation data on a 3-D human-in-the-loop simulator. Specifically, we compare virtual reality (VR) interfaces with a traditional interface, and examine the impacts that VR technology has on human properties in terms of model accuracy, performance, passivity and workload, demonstrating that VR interfaces have a positive effect on all aspects. In contrast to 1-D operation, we confirm that operators hardly attain passivity regardless of the network structure, even with the VR interfaces. We thus take the passivity-shortage-based control architecture and analyze the degree of passivity shortage. We then observe through user studies that operators tend to meet the degree of shortage needed to prove closed-loop stability.

In this paper, a compact mathematical model having an elegant structure, together with a generic control framework, are proposed for generic power systems dominated by power converters that are interconnected through a passive transmission and distribution (T&D) grid, by adopting the port-Hamiltonian (pH) systems theory and the fundamental circuit theory. The models of generic T&D lines are developed and then the model of a generic T&D grid is established. With the proposed control framework, the controlled converters are proven to be passive and Input-to-State Stable (ISS). The compact mathematical model is scalable and can be applied to power systems with multiple power electronic converters with generic passive controllers, passive local loads, and different types of passive T&D lines connected in a meshed configuration without self-loops, so it is very generic. Moreover, the resulting power system is proven to be ISS as well. The analysis is carried out without assumptions on constant frequency/voltage, constant loads, and/or lossless networks, except the need of passivity for all parts involved, and without using the Clarke/Park transformations or the graph theory. To simplify the presentation, three-phase balanced systems are adopted but the results can be easily adapted for single-phase or unbalanced three-phase systems.

Inverter-side current (ISC) control has been widely used in LCL-type grid-connected inverters due to its cost-effectiveness. However, the ISC-controlled inverters suffer from instability and injected grid current distortion under weak grid conditions, such as grid impedance variations and background harmonics. To solve these problems, this article presents an admittance shaping scheme based on capacitor voltage feedforward (CVF) for ISC-controlled LCL-type grid-connected inverters. A delay compensated proportional CVF method is used to shape the inverter output admittance to be passive almost up to the Nyquist frequency. Then, another high-pass filter-based CVF method is employed to shape the grid harmonic admittance to greatly reduce the admittance magnitude at the harmonic frequencies. Thanks to the proposed admittance shaping scheme, the ISC-controlled inverter system can operate stably regardless of the grid impedance and has excellent grid-current harmonic suppression capability. The effectiveness of the proposed admittance shaping scheme is verified by detailed simulation and experimental results.

This study introduces a nonfragile observer-based control strategy for power-line inspection robots (PILRs) that adeptly tackles input time delays while integrating passivity and $H_{\infty }$ performance. The research commences with the development of a nonlinear system model for PILRs, where the equilibrium manifold linearization method is employed to transform these underactuated systems into a linear framework using scheduling variables. Given the challenges posed by input delays, parameter disturbances, and uncertainties in real-world applications, this study proposes a robust observer-based control framework. Utilizing Lyapunov-Krasovskii functions and linear matrix inequalities (LMIs), the strategy confirms the system’s robustness in maintaining mixed passivity and $H_{\infty }$ performance. Simulation assessments substantiate the effectiveness of the proposed control approach, demonstrating its capacity to uphold system stability under diverse operational conditions. The strategy significantly enhances the reliability and safety of PILRs operating in complex environments, marking a pivotal advancement in robotic technologies for maintaining and inspecting utility infrastructures. This contribution not only strengthens the operational capabilities of PILRs but also provides a scalable approach to handling uncertainties and disturbances in robotic control systems.

This paper presents visual feedback 3D pose estimation/regulation methodologies in the sampled data setting by camera frame rates. Vision-based estimation/control problems have been studied by a number of research groups. While most works focus on the limitation of measured outputs, they conduct convergence/performance analysis under the assumption that visual measurements extracted from a camera are continuously available. However, the camera frame rates including image processing time often cannot be neglected compared with other computation time. In view of this fact, this paper newly proposes visual feedback pose estimation/regulation techniques under the situation that visual measurements are sampled due to the frame rates. The problem settings are first provided. Then, the pose estimation/regulation methods with sampled visual measurements are proposed. The convergence/performance analysis is conducted by the fusion of a Lyapunov-based approach and an event-triggered control technique. The present analysis scheme provides us guidelines for the design of estimation/control gains guaranteeing desired convergence/performance. The effectiveness of the present technique is verified via simulation and an experiment with real hardware.

The DXHS algorithm was proposed as an active noise control method and is often referred to as an adaptive method. This paper shows that the DXHS algorithm is a dynamical system that is equivalent to a passive internal model for sinusoidal signals. It follows that the disturbance attenuation ability is a consequence of the internal model principle, although the DXHS algorithm is proposed based on the standard way of thinking for adaptive methods. Moreover, the closed-loop system stability is guaranteed for strictly passive secondary paths.

In the present work, we introduced a novel way to study the Tafel slope of titanium in passive state based on potentiodynamic test with a break by potentiostatic polarization. The power law model as well as surface analysis methods such as AES and XPS were also introduced to character the thickness and composition of the film. Results indicate that the Tafel slope of titanium electrode in the passive state increases with the applied overpotential. The anodizing constant is found to be equal to about 0.24–0.46 Å/s and 4–10 Å/V. The results showing highly consistent with AES and XPS results. The passive film are mainly composed of TiO2 predominantly outer layer, and titanium sub-oxide, Ti(OH)x predominantly inner layer.

Nitrogen processed, cold sprayed commercially pure (CP)-Al coatings on Mg-based alloys mostly lack acceptable hardness, wear resistance and most importantly are highly susceptible to localized corrosion in chloride containing solutions. In this research, commercially pure α-Ti top coating having good pitting potential (∼ 1293 mVSCE), high microhardness (HV0.025: 263.03) and low wear rate was applied on a CP-Al coated Mg-based alloy using high pressure cold spray technology. Potentiodynamic polarization (PDP) curves indicated that the probability of transition from metastable pits to the stable pits for cold spayed (CS) Al coating is considerably higher compared to that with the CS Ti top coating (for Ti/Al/Mg system). In addition, CS Ti top coating was in the passivation region in most pH ranges even after 48 h immersion in 3.5 wt% NaCl solution. The stored energy in the CS Ti top coating (as a passive metal) was presumed to be responsible for the easy passivation. Immersion tests indicated no obvious pits formation on the intact CS Ti top coating surface and revealed effective corrosion protection performance of the CS double layered noble barrier coatings on Mg alloys in 3.5 wt% NaCl solution even after 264 h.

Summary: This article solves event‐triggered pinning control for passivity and synchronization problems of directly coupled delayed reaction‐diffusion neural networks (CDRDNNs). Outer coupling matrix of the presented model can be direct, while previous literature referred to reaction‐diffusion neural networks usually assumed this matrix undirected simply. First, through exploiting appropriate event‐triggered pinning protocol, passivity and synchronization criteria are acquired for directly CDRDNNs on account of Lyapunov functional and inequality techniques. After that, we also deal with event‐triggered pinning passivity and synchronization for undirected CDRDNNs. In the end, the effectiveness of these obtained results is verified by given examples. [ABSTRACT FROM AUTHOR]

My aim in this paper is to examine some of the distinctive facets of human action in Spinoza's philosophy and show their intrinsic connection with each other. By analyzing in detail how Spinoza addresses different aspects of human action in his main work, the Ethics, it is possible to notice that for him free human agency implies two interrelated features: on the one hand, the adequate knowledge of the causes that determine it, and, on the other hand, a growing capacity to impact with greater power the scenarios in which it takes place. Thus, in contrast with quietist and passive readings, I show in the following that the two aforementioned characteristics are part of the Spinozian philosophical conception of agency as such. By pursuing this line of thought, it is also possible to establish a link--not always noticed in the secondary literature--with some of the central lines of thought contained in the Theological-Political Treatise. In discussing these theses, I advance the idea that the Spinozian conception of human agency involves a serious readjustment of the metaphysical vision of the agent, a change in her conduct and ethical practices, and an altogether different conception of politics and religion. [ABSTRACT FROM AUTHOR]

This study considers the stability and passivity analysis of discrete-time systems with variable time-lags, saturation overflow nonlinear effects and external disturbances. Summation inequality based on free-weighting matrices is employed to develop an enhanced stability criterion that is in the form of linear matrix inequalities. A sufficient passivity condition for discrete-delayed systems involving overflow nonlinearities and subjected to external interferences is also proposed. Illustrative examples are presented to demonstrate the effectiveness of the obtained results. [ABSTRACT FROM AUTHOR]