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This paper investigates the stabilization problem for cyber‐physical systems subject to positive constraint and denial‐of‐service (DoS) attacks using the event‐triggered scheme. Unlike traditional modeling of cyber physical systems with DoS attack, this paper establishes a positive switched system model composed of two positive subsystems that according to the DoS attack is active or inactive. Considering the effect of positive constraint and DoS attack, a 1‐norm‐based event‐triggered mechanism is proposed in the sleep interval of DoS attacks. By incorporating switching theory with event‐triggered mechanism, the sufficient condition of positive property and exponential stabilization for the considered system is established. Thereafter, the gain matrix of the controller is calculated by matrix decomposition technique. Furthermore, the Zeno behavior is eliminated with a lower bound of the event‐triggered interval. Finally, an example is carried out to verify the validity of the theoretical results. [ABSTRACT FROM AUTHOR]

Synchronized space vector pulse width modulation (SSVPWM) is widely employed in high‐power AC drive systems. The existing methods are carrier‐based, in which the carrier ratio, position of samples, and switching sequences used to generate every sample for a given SSVPWM are settled, which causes two problems: (i) the control delay changes, and a voltage phase modulation error appears suddenly during transition between different SSVPWMs with different carrier ratios, which causes motor current spikes; (ii) due to the particular switching sequences, some kinds of SSVPWM cannot get into six‐step operation by overmodulation. This paper proposes an improved type of SSVPWM based on switching angles, in which the carrier ratio of a given SSVPWM can change flexibly, and the problems mentioned above can be solved. Theories including switching angle calculation, overmodulation strategy, carrier ratio setting principle, and transition rules between different SSVPWM modes are given in this paper. Meanwhile, the switching angles change linearly with modulation index which makes it easy to implement, and the modulation error in the overmodulation region is effectively limited so that the proposed scheme is suitable in the whole modulation index range. A case study of a 5.5‐kW experimental platform is presented to validate the proposed method. © 2024 Institute of Electrical Engineers of Japan and Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

This article revisits saturated stabilization of the feed‐forward systems that are subject to lower‐order perturbations, with the purpose of providing new analysis approaches. To carry out the saturation reduction analysis, we do not use the existing time‐interval based contradiction approach, but propose a Lyapunov function method; to deal with the reduced system (the closed‐loop system that does not contain saturation any longer), we do not use the "adding a power integrator" backstepping scheme, but propose an approach which is established by jointly using the vector Lyapunov function theory, a matrix measure stability theory and the switching systems theory. As a result, a quite number of inequality computations can be avoided, and the stability conditions summarized in two analysis procedures can be expressed by directly using the system parameters. This article also shows that the established approaches are applicable to the uncertain feedforward systems subject to linear input perturbation and consequently, allows to present new stabilizing control laws for several intractable under‐actuated systems. [ABSTRACT FROM AUTHOR]

Different stimuli can potentially activate overlapping populations of neurons in the brain. How does the brain maintain information about multiple items? Here, we describe a new theory: neurons might switch back and forth between encoding each item across time. Recent statistical advances have allowed neurophysiology studies to probe for such activity fluctuations, generating support for this theory and opening intriguing new research directions. Many open questions remain, such as the time scale of activity fluctuations, the manner in which they are coordinated across (and read out from) neural ensembles, and the implications for perceptual binding, neural oscillations, and cognitive processes like attention, memory, and thought. Our ability to perceive multiple objects is mysterious. Sensory neurons are broadly tuned, producing potential overlap in the populations of neurons activated by each object in a scene. This overlap raises questions about how distinct information is retained about each item. We present a novel signal switching theory of neural representation, which posits that neural signals may interleave representations of individual items across time. Evidence for this theory comes from new statistical tools that overcome the limitations inherent to standard time-and-trial-pooled assessments of neural signals. Our theory has implications for diverse domains of neuroscience, including attention, figure binding/scene segregation, oscillations, and divisive normalization. The general concept of switching between functions could also lend explanatory power to theories of grounded cognition. [ABSTRACT FROM AUTHOR]

This paper addresses the problem of designing secure control for networked multi-agent systems (MASs) under Denial-of-Service (DoS) attacks. We propose a constructive design method based on the interaction topology. The MAS with a non-attack communication topology, modeled by quasi-Abelian Cayley graphs subject to DoS attacks, can be represented as a switched system. Using switching theory, we provide easily implementable sufficient conditions for the networked MAS to remain asymptotically stable despite DoS attacks. Our results are applicable to both continuous-time and discrete-time systems, as well as to discrete-time systems with variable steps or systems that combine discrete and continuous times. [ABSTRACT FROM AUTHOR]

Summary: In this paper, the secure group consensus is investigated via periodic event‐triggered output feedback control for nonlinear multi‐agent systems subject to multiple attacks, where replay attacks and denial‐of‐service attacks are considered simultaneously. To avoid uninterrupted communication between agents, a novel fixed/switching continuous‐discrete compensator is first put forward by introducing a discrete‐time triggering mechanism in relative output signals. Then, with the help of the gain control technique, a compensator‐based periodic event‐triggered secure control protocol is established, which includes a triggering mechanism and an output feedback controller that both are discrete‐time. Particularly, Zeno behavior and continuous monitoring of the triggering function are naturally avoided compared with existing event‐triggered control protocols. Further, by combining the Lyapunov‐Krasovskii functional approach with switching topology theory, the secure group consensus is successfully achieved under the designed secure control protocol, meanwhile, the negative effect of multiple attacks on the system is compensated. Finally, two simulation examples are applied to verify the effectiveness of proposed control protocols. [ABSTRACT FROM AUTHOR]

Among the long-standing efforts to elucidate the physical mechanisms of protein- ligand catch bonding, particular attention has been directed at the family of selectin proteins. Selectins exhibit slip, catch-slip, and slip-catch-slip bonding, with minor structural modifications causing major changes in selectins' response to force. How can a single structural mechanism allow interconversion between these various behaviors? We present a unifying theory of selectin-ligand catch bonding, using a structurally motivated free energy landscape to show how the topology of force-induced deformations of the molecular system produces the full range of observed behaviors. We find that the pathway of bond rupture deforms in non-trivial ways, such that unbinding dynamics depend sensitively on force. This implies a severe breakdown of Bell's theory-a paradigmatic theory used widely in catch bond modeling-raising questions about the suitability of Bell's theory in modeling other catch bonds. Our approach can be applied broadly to other protein-ligand systems. [ABSTRACT FROM AUTHOR]

Mobile payment (m-payment) is no longer an unknown technological innovation due to mobile technology advancement. While many past studies have been conducted in this area, they assume that a user will only need to consider m-payment without cash impediments. Hence, they fail to consider the influence of cash within the study of m-payment. Given this limitation, the study draws on migration, regret, innovation resistance, status quo bias, and incentive theories to examine the switching intention from cash to m-payment based on a push-pull-mooring framework. A total of 250 usable sample sizes were adopted, with the conceptual model empirically validated using a PLS-SEM. All the findings in this study were supported except for the relationship between perceived monetary rewards and switching intention, and the risk barrier and inertia. The findings of this study benefit managers and practitioners from both theoretical and practical backgrounds. [ABSTRACT FROM AUTHOR]

Purpose: The switching of motion states and grazing/sliding motion for an oscillator are typical dynamic phenomena in some discontinuous/non-smooth dynamical systems such as friction/vibro-impact systems with clearance. This work describes the behavior of discontinuous dynamics for a two-degree-of-freedom (2-DOF) frictional collision system with intermediate rigid constraint and unilateral elastic collision under periodic excitation by flow switching theory, where this kind of system considered in this paper can better reflect the actual working conditions of a class of mechanical vibration systems and is few researched at present. Methods: First, the physical model studied in this paper is introduced and analyzed in depth (such as motion state, motion equation, etc.). Second, based on the discontinuity/nonsmoothness of oscillator's movement, the absolute and relative phase planes of oscillator's movement are divided into multiple dynamic domains and dynamic boundaries such that the vector field in each dynamic domain is continuous. Third, according to the difference between the static friction coefficient and the dynamic friction coefficient of the system, the flow barrier which is generated on the velocity boundary and prevents the boundary flow from flowing to the domain is studied. Results: By means of the vector field and G-function, the criteria for the switching of each state of motion on the separation boundaries are obtained. And then, the conversions of some typical movements are more intuitively demonstrated through numerical simulation based on MATLAB software. A multi-body dynamics model of this 2-DOF system is developed in MSC Adams to help us visualize the actual dynamics behavior under real dimensional system parameters and compare it with the foregoing numerical simulation for a group of periodic motion data, and the results are nearly consistent. Conclusion: This work further improves the flow switching theory and brings a theoretical reference for multi-constrained mechanical systems. [ABSTRACT FROM AUTHOR]

Harvey's (1978) switching theory has been widely used to theorize investments in the built environment. Crucially, in switching theory no distinction has been made between investments in the construction of the newly built environment and investments into the existing built environment. The distinction between these two types of switching is key to unveiling the relations between how value is produced, rents are extracted and interest payments are made as investments flow with the real estate sector, and the implications that such switching has for displacement. I discuss the distinction between different types of switching and the implications thereof by analysing the ebb and flow of investments in Spanish real estate from 2000 to 2007 and from 2014 to 2018. On the one hand, I claim that the two switching waves were qualitatively different in so far as capital was fixed in the built environment through the construction of new buildings between 2000 and 2007, whereas from 2014 to 2018 capital was fixed in existing buildings. In the first switching phase, value was produced and land rents were extracted, whereas the second switching phase was characterized mainly by rent extraction. On the other hand, the first switching moment entailed an increase in housing provision, whereas the second switching moment led to widespread displacement of the population. [ABSTRACT FROM AUTHOR]

In response to the Scientific Revolution of the 17th century, Immanuel Kant put forward a transcendental philosophy which distinguished between the appearance and the thing-in-itself (das Ding an sich), in the belief that people can only know appearances, but not things-in-themselves. The fact that contemporary philosophy has gone far beyond transcendental philosophy can be seen clearly in the following respects: the response to the Scientific Revolution; the dualistic theory of qualities; the two concepts of the thing-in-itself; and how to know the thing-in-itself. In order to deepen the discussion of the thing-in-itself, it is necessary to introduce probing new questions and attempt to elucidate a switching theory of reality that distinguishes between the meaning-impoverished thing-in-itself and the meaning-rich thing-in-itself, and advocates placing the focus of philosophical thinking on the latter. Basing ourselves on the switching theory of reality and the total perspective concept that it implies allows us to better understand man's place in the universe and the mission of philosophy in the post-metaphysical era. [ABSTRACT FROM AUTHOR]

We aim to uncover theoretical mechanisms associated with potential negative (i.e., multitasking) and positive (i.e., self-regulation) aspects of cell phone use (CPU) for academic performance in young adults. We hypothesized that, according to the Switch-Load Theory, repeated CPU during academic activities (CPU_Multitasking) would relate negatively, whereas, according to Zimmerman's Theory of Self-Regulated Learning, CPU for self-regulated learning behaviors (CPU_SRLBehavior) would relate positively to the academic performance of undergraduate students. 525 (75.4% female) undergraduate students from a large public university participated in this study during fall 2019 by completing validated quantitative surveys accessing their CPU and academic performance. Spearman's rho was used to compute the correlations and hierarchical regression was used to analyze the variance. Spearman rank-order coefficient showed that CPU_Multitasking relates negatively, but CPU_SRLBehavior is unrelated to the college GPA of undergraduate students. Hierarchical regression showed that CPU_Multitasking was not a significant predictor of academic performance. Young adults who switch to their cell phones during class or study-related activities are more likely to have lower performance in exams as CPU_Multitasking costs time and efficiency (Switch Load Theory). Young adults who use their cell phones for self-regulated learning behavior are less likely to have an impact on their academic performance as CPU_SRLBehavior helps regulate habits but not learning processes. With the known theoretical mechanisms for CPU multitasking and SRL Behavior, this study provides a guiding document for educational computing system practitioners to explore more theory-driven empirical approaches in the field of CPU and academic success. [ABSTRACT FROM AUTHOR]

Quine showed in Quine (1953) that unate Boolean functions have properties not shared by general functions. Among such properties are the uniqueness of their irredundant sum-of-products representation and the relative ease with which this representation can be obtained. This paper investigates to what extent such properties extend to functions that are unate only in a subset of variables. Some results seem to stand out. For instance, subproducts of unate variables form a "prefix set" which does not depend on the particular irredundant sum-of-product representation. A second result is that every sum-of-products expression is decomposable into parts, one per prefix, that can be minimized independently. Finding the shortest expression can then be (recursively) decomposed into smaller subproblems, a departure from traditional monolithic approaches (McCluskey, 1986; Brayton et al., 1984). The results lead naturally to the definition of the class of block-unate functions, Such functions have a unique irredundant sum-of-products representation, which can be recognized and constructed from a truth table or a minterm list in polynomial time. This is a departure from the general construction problem, which is NP-complete (Allender et al., 2008; Umans et al., 2006). [ABSTRACT FROM AUTHOR]

Starting from a reformulation of the mass balance law based on the Bilby–Kröner–Lee (BKL) decomposition of the deformation gradient tensor, we study some peculiar mechanical aspects of growth in a monophasic continuum by regarding the reformulated mass balance equation as a non-holonomic and rheonomic constraint. Such constraint restricts the admissible rates of the growth tensor, i.e., one of the two factors of the BKL decomposition, to comply with a growth law provided phenomenologically. For our purposes, we put the constraint in Pfaffian form, and treat time as a fictitious, additional Lagrangian parameter, subjected to the condition that its rate must be unitary. Then, by taking some suggestions from the literature, we assume the existence of generalized forces conjugated with the virtual variations of the growth tensor, and we write a constrained version of the Principle of Virtual Work (PVW) that leads to a mixed boundary value problem whose unknowns are the motion, the growth tensor, and the Lagrange multipliers of the considered theory. This allows to extrapolate a physical interpretation of the role that the growth-conjugated forces play on the components of the growth tensor, especially on the distortional ones, i.e., those that are not directly related to the variation of mass of the body. The core message of our work is conceptual: we show that the growth laws usually encountered in the literature, which are prescribed phenomenologically, but may be difficult to justify theoretically, can be put in the framework of the PVW by regarding them as constraints. Moreover, we retrieve more particularized frameworks of growth available in the literature, while being able to switch to a theory of growth of grade one, such as a Cahn–Hilliard model of growth. [ABSTRACT FROM AUTHOR]

Random jump of network communication topology challenges the tracking accuracy of linear switched reluctance motor (LSRM) system. This paper studies the pilot‐following consensus control of the multiple direct‐drive motion system (MDDMS) with semi‐Markov jump topology. The mathematical model of LSRM is constructed and the multi‐phase excitation strategy is studied. The directed graph is used to model the information transmission among the leaders and follower, and a new mechanism consensus based on previous states is provided. A consensus system based on semi‐Markov jump topology is constructed and the problem of consensus is shifted into a problem of stability analysis. A sufficient condition for consensus problem is obtained by using semi‐Markov switching system theory and graph theory. The MDDMS achieves consensus in the form of exponential convergence under the designed consensus controller. Several groups of simulation results verify the effectiveness of the proposed consensus control method. [ABSTRACT FROM AUTHOR]

A distributed H ∞ filtering issue is addressed in this paper for discrete-time nonlinear systems in the face of replay attacks over sensor networks, where an indicator variable is introduced to describe whether a replay attack is launched by the adversaries. First, an interesting pattern dependent on three parameters including a time-varying one is established to account for the temporal behavior of malicious attacks. Then, taking advantage of such a model, the resulting filter dynamic is transformed into a switching system with a subsystem with time-varying delays. By means of the famous switching system theory, a sufficient condition guaranteeing the H ∞ performance is derived to disclose the tolerant attack condition, that is, the attack-active duration and proportion. In addition, the applicable filter gains are achieved with the aid of the solutions of matrix inequalities. Finally, an example is purposively given to adequately illustrate the availability of the developed secure filtering strategy. [ABSTRACT FROM AUTHOR]

In this paper, the discontinuous dynamic behavior of a two-degree-of-freedom frictional collision system including intermediate elastic collision and unilateral elastic constraints subjected to periodic excitation is studied by using flow switching theory. In this system, given that the motion of each object might have a velocity that is either greater than or less than zero and each object experiences a periodic excitation force that has negative feedback, because the kinetic and static friction coefficients differ, the flow barrier manifests when the object's speed is zero. Based on the discontinuity or nonsmoothness of the oscillator's motion generated by elastic collision and friction, the motion states of the oscillator in the system are divided into 16 cases and the absolute and relative coordinates are used to define various boundaries and domains in the oscillator motion's phase space. On the basis of this, the G-function and system vector fields are used to propose the oscillator motion's switching rules at the displacement and velocity boundaries. Finally, some dynamic behaviors for the 2-DOF oscillator are demonstrated via numerical simulation of the oscillator's stick, grazing, sliding and periodic motions and the scene of sliding bifurcation. The mechanical system's optimization designs with friction and elastic collision will benefit from this investigation's findings. [ABSTRACT FROM AUTHOR]

This paper investigates a practical time-varying formation control method for quadrotors subjected to disturbances, uncertainties, and switching-directed topologies. A fully distributed formation control scheme is proposed using a linear-velocity independent position controller (LVIPC) and a nonsingular terminal sliding mode attitude controller (NTSMAC). A distributed observer is adopted to eliminate the measurement of linear-velocity states, and only local neighbor states are needed to realize formation flight. A time-varying nonsingular terminal sliding mode manifold is designed to suppress the reaching phase and ensure the finite-time convergence. Adaptive estimators are employed to remove the reliance on the prior knowledge of the upper bound of lumped uncertainties. It is then proven that all the closed-loop signals are bounded under the proposed method. Comparative experimental results based on a practical outdoor hardware solution are presented to confirm the effectiveness of the suggested control algorithm. [ABSTRACT FROM AUTHOR]

In this paper one industrial process and the automation of that industrial process are considered. In automation, the most important part is the controller. The controller is actually the brain of the process, and it regulates the switching on and off of all the elements involved in the process itself. The controllers that are used in industrial automation are called programmable logic controllers (PLC controllers). With an example it is shown how the PLC controller can be programmed with a Ladder Diagram. PLC programming involves creating a set of instructions that govern the behavior of a PLC to control machinery and processes. These instructions are written using specialized software tools and are executed in a sequential manner. The primary objectives of PLC programming are to ensure the safe and efficient operation of automated systems, maintain process accuracy, and facilitate quick responses to changing conditions. [ABSTRACT FROM AUTHOR]

This research note reviews theories of religious switching and polarization and presents data from national studies to trace how the determinants of religious switching have played out in the lives of US Jews. The growing shares of the most religious and the most secular segments, particularly among the young, explain the hollowing of the middle, and the shifts in the denominational landscape of American Jewry. Utilizing primarily Pew Research Center's 2013 and Pew Research Center's 2020 surveys, this note explores the consequences of religious polarization on cohesion among US Jews broadly and with respect to Israel specifically. [ABSTRACT FROM AUTHOR]

Non-equilibrium work switching simulations and Jarzynski's equation are a reliable method for computing free energy differences, Δ A low → high , between two levels of theory, such as a pure molecular mechanical (MM) and a quantum mechanical/molecular mechanical (QM/MM) description of a system of interest. Despite the inherent parallelism, the computational cost of this approach can quickly become very high. This is particularly true for systems where the core region, the part of the system to be described at different levels of theory, is embedded in an environment such as explicit solvent water. We find that even for relatively simple solute–water systems, switching lengths of at least 5 ps are necessary to compute Δ A low → high reliably. In this study, we investigate two approaches towards an affordable protocol, with an emphasis on keeping the switching length well below 5 ps. Inserting a hybrid charge intermediate state with modified partial charges, which resembles the charge distribution of the desired high level, makes it possible to obtain reliable calculations with 2 ps switches. Attempts using step-wise linear switching paths, on the other hand, did not lead to improvement, i.e., a faster convergence for all systems. To understand these findings, we analyzed the solutes' properties as a function of the partial charges used and the number of water molecules in direct contact with the solute, and studied the time needed for water molecules to reorient themselves upon a change in the solute's charge distribution. [ABSTRACT FROM AUTHOR]

Modern trends in the information technology have led to the fact that entire systems of infrastructure are becoming software-defined. Modern hyper-converged solutions use software-defined networking and soft switches for the hypervisor networking subsystem. The paper goal is to study traffic processing in hyperconverged structures with software switching based on OpenFlow versus traditional approaches. The features of the hyperconverged solutions network infrastructure are considered, approaches to the study of software-defined environments are described. A model of the processing traffic internal structure of a converged node, combining the functions of a hypervisor, a storage system and a switch, is proposed. Interface models reproduced traffic switching with the traditional approach and with higher-level OpenFlow processing have been developed. The approaches to the implementation of the developed models based on experimental studies of network equipment are described. The results of an experimental study of a network node and a synthesized model are presented. The possibility of implementing the proposed approaches within the specified accuracy are described. [ABSTRACT FROM AUTHOR]

A novel method for measuring the complex magnetic susceptibility of magnetic nanoparticles (MNPs) has been developed by a broadband microstrip line-type probe with a frequency range of up to 50 GHz. Two external orthogonal DC fields, Hhard and Heasy, were applied to change the susceptibility of MNPs (Streptavidin coated, 200 nmϕ, number of MNPs about 1010) based on magnetization switching theory. The susceptibility of MNPs in the liquid, solid state, and after biotin-avidin reaction with polymer beads (2 μmϕ, number of polymer beads about 108) was evaluated. A clear FMR frequency of MNPs and the same FMR frequency shift trend as Hhard changed was observed around 2–10 GHz in both liquid and solid states. The susceptibility of MNPs reached maximum when Hhard was 0.1 T which is approximately equal to Heasy (0.135 T). The maximum values of real and imaginary parts increased by a factor of 3.39 and 1.66 compared to when Hhard was 0. The obtained results indicate that the magnetic anisotropy was successfully controlled in the liquid and solid states of MNPs aggregate. Furthermore, after the biotin-avidin reaction of MNPs with polymer beads, the imaginary part of susceptibility showed a decreasing trend regardless of the increase in Hhard, and its half-width expanded by 35.1% at maximum when Hhard was 0.15 T. [ABSTRACT FROM AUTHOR]

The fixed-time synchronization of time-delay interconnected memristive neural networks is probed in this article. Firstly, according to the conventional controller, a new type of switching controller is proposed, which can complement each other. By utilizing the theory of Lyapunov stability and differential inclusion, it is proved that interconnected memristive neural networks can achieve synchronization within a fixed time under the designed controller. In addition, to control engineering costs, the upper limit of energy consumption, which is produced by the controller from the initial time to the settling-time, is estimated. Finally, numerical examples are provided to verify the validity of the theoretical results. [ABSTRACT FROM AUTHOR]

In the current work, a temperature-responsive system consisting of a fatty acid-based hydrophobic deep eutectic solvent and a choline chloride (ChCl)-based hydrophilic deep eutectic solvent was innovatively developed. It was used to extract and separate polar compounds (chlorogenic acid, rutin, hyperin, isoquercetin, hydroxy-α-sanshool) from Zanthoxylum bungeanum Maxim. peels (ZBMP). Different molar ratios of the hydrophobic deep eutectic solvent (DES) composed of decanoic acid (DA)-octanoic acid (OA) and hydrophilic DES composed of ChCl-levulinic acid (Lev) were chosen as the switching medium. Under the optimal extraction conditions, the TRBDES consisting of hydrophilic DES (ChCl: Lev/1:2): hydrophobic DES (OA: DA/2:1): H 2 O (v/v/v,5/5/1) demonstrated a greater total extraction rate and distributive efficiency than the conventional solvents. High DPPH radical scavenging capacity of target compounds (IC 50 = 0.29 mg/mL) from the bottom phase recovered by D101 macroporous resin. Hydrogels prepared by DES containing extracts in the top phase showed significant inhibition of E. coli (15.5 ± 0.7 mm). and S. aureus (21.0 ±1.4 mm). The solvent morphologies and the intrinsic switching mechanism were observed and illustrated. Moreover, density functional theory (DFT) calculations showed that hydrogen bond production is crucial for extraction. This work provides a resource for exploring and utilizing TRBDES for environmentally friendly extraction of various bioactive active ingredients from plant sources. [Display omitted] • A biphasic deep eutectic solvent-based system with temperature-responsive behavior. • This solvent was applied to extract and pre-separate active ingredients. • The temperature-switching mechanism was investigated and explored. • The extraction mechanism was demonstrated by density functional theory. • Deep eutectic solvent of the top phase containing extracts was fully utilized. [ABSTRACT FROM AUTHOR]

• 2 mmol/L Ca2+ significantly enhances the nitrogen removal performance of AnGS. • Suitable Ca2+ optimized the EPS composition to enhance the stability of AnGS. • The mode switching theory of AnGS to defend against excess Ca2+ was proposed. • "Precipitate shield" protects AnGS from the stress of high concentration Ca2+. • "Precipitate shield" has poor mass transfer efficiency (NH 4 +-N, NO 2 --N, etc.). Anammox granular sludge (AnGS) has received considerable attention due to its low carbon footprint (less aeration energy and carbon source consumption) and high biomass density, but growth rate and stability are still the bottlenecks of AnGS process. Calcium ion (Ca2+) is essential for the growth of anaerobic ammonium oxidation bacteria (AnAOB) and plays an important role in the formation and stability of AnGS. Response of AnGS to Ca2+ under different concentrations was comprehensively investigated by multi-spectral and metagenomics analysis in four aspects: nitrogen removal performance, surface morphology, extracellular polymeric substance (EPS) composition and characterization, and microbial community. The nitrogen removal efficiency was significantly enhanced at appropriate Ca2+ concentration (2 mmol/L), owning to the more favorable morphology and functional microbial composition of AnGS. However, the nitrogen removal performance of AnGS declined with the Ca2+concentration increased from 2 to 8 mmol/L, due to the negative effects of excess Ca2+on EPS, mass transfer efficiency, and functional microorganisms. Meanwhile, an unexpected slight "rebound" of nitrogen removal efficiency was observed at Ca2+ = 6 mmol/L and attributed to the defense mode transformation of AnGS (from "ion stabilization" to "precipitate shield" modes) against excess Ca2+ stress. Based on the findings, the response mechanism of AnGS to Ca2+ with different concentrations was established. Our results enhanced the understanding of the interaction between AnGS and Ca2+, which may be valuable for filling the theoretical gap in enhancing the granulation and stability of AnGS and providing a reference for the practical operation of the AnGS process. [Display omitted] [ABSTRACT FROM AUTHOR]

Two-dimensional topological insulator bismuth selenide (Bi2Se3) nanosheets (NSs) embedded in poly-methyl methacrylate (PMMA) are employed for the first time for the resistive switching (RS) application. Hexagonal 2D Bi2Se3 NSs are synthesized by a simple solvothermal method and combine with PMMA at different weight percentages of 2D Bi2Se3. Field emission scanning electron microscopy and transmission electron microscopy along with other characterizations such as X-ray photoelectron spectroscopy and Raman spectroscopy were performed for the characterization of Bi2Se3@PMMA hybrid system. The composite was deposited on a transparent, flexible polyethylene terephthalate substrate to form Ag/Bi2Se3@PMMA/indium doped tin oxide memory cell. I-V characteristics of the device revealed a stable and non-volatile memory effect. The device shows a significantly high resistance (RHRS/RLRS) ratio, more than 103, high retention time (more than 9000 s) with high reproducibility over a large number of (105) ac cycles. From the experimental data, RS performances are explained by using a charge trapping–detrapping mechanism. Owing to the increasing interest in flexible electronics, bending tests are carried out at various bending diameters (10–30 mm) to show the mechanical robustness of the proposed device. [ABSTRACT FROM AUTHOR]

Lithium niobate single-crystal films are interesting for the integration of optoelectronic and surface acoustic wave devices. However, the domains have the preferred orientations, which limit their application in non-volatile memory devices. Here, we fabricated 5% Mg-doped LiNbO3 single-crystal films by ion-slicing of surface layers of bulk lithium niobate single-crystals. The Mg doping can improve the electrical performance of the films with the appearance of a definitive coercive voltage irrespective of applied voltages in polarization-voltage (P-V) hysteresis loops, unlike the undoped films where the apparent coercive voltages in P-V hysteresis loops equal the maximum applied voltages. Subsequent unipolar pulse stressing shows comprehensive charge injection into the films to occur at repetitive periodicities below 0.5 s that can symmetrize P-V hysteresis loops along the voltage axis. The injected charge in contradiction to an internal imprint field can change domain switching dynamics that can be described by the model of a non-ferroelectric passive layer in series with an ideal ferroelectric layer. The dielectric permittivities at low frequencies show the Maxwell-Wager relaxation of the injected charge with the broad distribution of relaxation times. As the periodicity is above 2 s, the injected charge within each cycle can be driven out of the film during intermittent time by the imprint field. This study shows the possibility of charge injection in stabilization of bipolar domain orientations in LiNbO3 single-crystal films. [ABSTRACT FROM AUTHOR]

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When we study the Karnaugh map in the switching theory course, we learn that the ones in the map are combined in rectangles whose length and width must be a power of two. The result is the logic function described as a sum of products. This paper shows that we can also make groups where the length and width of the rectangles are equal to three. This results in a logic function that is simpler than the sum of products in terms of logic gates, leading to more hardware-efficient circuits. This idea is extended later in the paper to other groups of elements. Finally, a new perspective on the Karnaugh map that integrates the proposed approach with the conventional one is provided. This can be used in switching theory courses to improve the explanation of the Karnaugh map. [ABSTRACT FROM AUTHOR]

In this paper, we demonstrate a device using a Ni/SiN/BN/p+-Si structure with improved performance in terms of a good ON/OFF ratio, excellent stability, and low power consumption when compared with single-layer Ni/SiN/p+-Si and Ni/BN/p+-Si devices. Its switching mechanism can be explained by trapping and de-trapping via nitride-related vacancies. We also reveal how higher nonlinearity and rectification ratio in a bilayer device is beneficial for enlarging the read margin in a cross-point array structure. In addition, we conduct a theoretical investigation for the interface charge accumulation/depletion in the SiN/BN layers that are responsible for defect creation at the interface and how this accounts for the improved switching characteristics. [ABSTRACT FROM AUTHOR]

In this study, a new square-based fiber Bragg grating (FBG) sensor network model is proposed to address possible link failures in FBG sensor networks and improve their reliability. Graph theory and optical switching are simultaneously applied to these sensor networks to improve their self-healing ability; the FBG sensor network is regarded as a directed graph. Three commonly used self-short-circuit algorithms are compared in terms of the self-healing capabilities that they provide to the optical fiber sensor network. Among these, the shortest-path faster algorithm achieved a high, nearly 90% repair accuracy and had an average repair time of 0.103 s, the shortest in this study. The newly designed FBG self-healing network can be reorganized and repaired when local damage occurs, thereby improving its reliability. [ABSTRACT FROM AUTHOR]

A mixed graph is a set of vertices together with an edge set and an arc set. An (m; n)-mixed graph G is a mixed graph whose edges are each assigned one of m colours, and whose arcs are each assigned one of n colours. A switch at a vertex v of G permutes the edge colours, the arc colours, and the arc directions of edges and arcs incident with v. The group of all allowed switches is Γ. Let k ≥ 1 be a fixed integer and Δ a fixed permutation group. We consider the problem that takes as input an (m,n)- mixed graph G and asks if there is a sequence of switches at vertices of G with respect to Δ so that the resulting (m,n)-mixed graph admits a homomorphism to an (m,n)-mixed graph on k vertices. Our main result establishes that this problem can be solved in polynomial time for k ≤ 2, and is NP-hard for k ≥ 3. This provides a step towards a general dichotomy theorem for the Δ-switchable homomorphism decision problem. [ABSTRACT FROM AUTHOR]

There are many ways to gain knowledge about architecture: sensing, drawing, building, and thinking for example. When thinking about architecture, leaving the interior point of view and looking from the outside toward architecture offers a broad variety of perspectives. This helps us to understand, moreover to develop different design approaches for architectures: Looking from the outside, architectural design implies a certain attitude toward the world. Using a film lense for this look, I will reveal the relevance of cinematic techniques. Thus, in this article I suggest switching to film theory and history. With the help of director Sergei Eisenstein and architect Le Corbusier we will explore how architecture and film share an intensive relationship with images. If we take a closer look, we will see that montage as a cinematic technique to attach images reveals characteristics of architecture that we might not have been aware of - the relevance of gaps, for example. Thus, images are entities with which to transmit knowledge from film to architecture and back, while montage is the practice of working with images and their inherent knowledge. Accordingly, this article aims to analyze how montage is used as image practice in the work of Eisenstein and Le Corbusier. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel HEMTG is established to calculate the harmonic intensity injected into the power grid by the transformer under the action of different GIC. • A harmonic simulation model of the UHV AC/DC power grid under GIC is established, and the accuracy of the simulation model is confirmed by theoretical analysis. • The HSS model under GIC is formulated, and the accuracy of its calculation results is validated using the simulation model. Utilizing this model, the distribution and propagation characteristics of harmonics in the UHV AC/DC power grid under GIC conditions are analyzed. The power grid's geomagnetically induced currents (GIC) during geomagnetic storms, are associated with a broad and abrupt harmonic impact, with the potential for grid paralysis and extensive power outages in severe scenarios. Therefore, the harmonic characteristics of geomagnetically induced currents in China's ultra-high voltage (UHV) AC/DC power grid are analyzed in this paper. Firstly, a harmonic equivalent model of transformer GIC is established, and the injection of harmonics into the UHV AC/DC power grid during GIC events is quantified. Secondly, a harmonic state-space model is established by combining the 12-pulse converter switching function theory with the exponential Fourier series. The harmonic transmission and dynamic coupling characteristics of GIC in the UHV AC/DC power grid are analyzed using the harmonic equivalent model of the main transformer GIC and the harmonic equivalent model of the converter transformer GIC. Finally, a harmonic simulation model of the UHV AC/DC power grid under GIC is constructed using PSCAD, and the distribution of harmonics in the UHV AC/DC power grid under GIC is calculated. The calculations indicate that with 30 A injected GIC in the sending end transformers, the 2nd harmonic current on the sending end network side alone is 61.45 A, and the 3rd harmonic voltage on the valve side is 8.57 kV. The characteristics of harmonic transmission in the power grid result in a 2nd harmonic current of 34.87 A on the receiving end network side. Simultaneously, the total harmonic distortion of the AC power grid at the sending end is 2.35 %, surpassing the permissible limit established by the national standard. Consequently, this issue should be prioritized by the relevant power authorities. [ABSTRACT FROM AUTHOR]

It is widely known that uncertainties, unknown disturbances, asynchronous switching, and partial actuator faults are the major factors that affect system stability during actual industrial production. For the above problems, a method of iterative learning robust MPC hybrid fault-tolerant control for multi-phase batch processes with asynchronous switching in two-dimensional systems is proposed. Exceptionally, an equivalent extended asynchronous switching fault-tolerant control model, including a synchronous sub-model and an asynchronous sub-model, is built. Then, Lyapunov theory, switching system theory, and so on are used as the theoretical basis, and the sufficient conditions to guarantee the stable operation of the system are given. Combined with the given conditions, the control law gain, the shortest running time, and the longest running time are solved in real time to eliminate the asynchronous switching situation problem. The state deviations of the system are corrected in time by avoiding the accumulation of the system state deviations over time, thus improving the control performance of the system. Meanwhile, by combining real-time control law gains with information about the batch direction, the method can significantly reduce the learning period of the controller and provide better control performance along the batch direction. Finally, the feasibility of the proposed method is verified with simulation experiments of the injection molding process. • The gains of control law the proposed method is solved in real-time, which can avoid the negative effects of state deviation. • The proposed method can prevent asynchronous switching situations by giving switching signals in advance. • The proposed method can shorten the learning cycle of the controller and has better control performance in batch direction. [ABSTRACT FROM AUTHOR]

This article presents a Bayesian approach for sequential detection of anomalies in the motion of a target and joint tracking. The anomaly is modeled as a binary (on/off) switching unknown control input that goes into action (begins to exist, or "switches on") thereby modifying the object dynamics; and by ceasing its activity (becoming nonexistent, or "switching off") returns the dynamics to nominal. The developed Bayesian framework brings together random finite set (RFS) theory to represent the switching nature of the anomaly, and optimal joint input and state estimation to sequentially update a hybrid state that incorporates a random vector for the kinematic state and a Bernoulli RFS for the unknown control input. In addition, a closed-form solution, the Gaussian-mixture hybrid Bernoulli filter (GM-HBF), has been developed to provide a customized solution for dynamic anomaly detection in the maritime domain characterized by linear Gaussian target dynamics. Based on the Ornstein–Uhlenbeck dynamic model for vessels, where the evolution of the object velocity is governed by a piecewise mean-reverting stochastic process, the anomaly can be represented by a change in the long-run mean velocity (i.e., the unknown control input) from the nominal condition that forces the vessel to deviate from its standard route. We demonstrate the effectiveness of the proposed GM-HBF in both simulated and real-world maritime surveillance applications and test its performance in the face of false measurements, detection uncertainty, and sensor data gaps. [ABSTRACT FROM AUTHOR]

Keywords: Boolean function; discrete Fourier (Walsh-Hadamard) transform; maximum nonlinearity; amplitude; dimension of a Boolean function; extension of general affine group EN Boolean function discrete Fourier (Walsh-Hadamard) transform maximum nonlinearity amplitude dimension of a Boolean function extension of general affine group 177 192 16 06/17/22 20220601 NES 220601 Note: Originally published in Diskretnaya Matematika (2021) 33,No2, 66-85 (in Russian). Discrete Fourier (Walsh-Hadamard) transform, dimension of a Boolean function, extension of general affine group, Boolean function, maximum nonlinearity, amplitude It is important to note the value of group invariants in problems connected to classification of Boolean functions. [Extracted from the article]

In this study, we consider a new aspect of belief function or Dempster-Shafer theory to define a belief set and cosine similarity measure between two belief sets under uncertainty. For this purpose, firstly, the concept of belief sets will be represented as a triple vector space that is characterized by truth-belief degree, uncertainty-belief degree; and falsity-belief degree. Then, the cosine similarity measure between two belief sets is proposed to determine the degree of similarity between them. This measure is directly defined upon the framework of Dempster-Shafer theory without switching by other theories. Finally, an application of a new method in the decision-making process is provided in the medical diagnosis, when values were presented on the structure of belief set. Furthermore, a numerical example of the medical diagnosis is presented to show the effectiveness and flexibility of the proposed method. [ABSTRACT FROM AUTHOR]

In this work, atomically K1−xNaxNbO3 thin films are taken as examples to investigate the reversible and irreversible effects in a horizon plane, i.e., the changes of domain structures, phase states, free energies, etc., under a z-axis alternating current field via a phase-field method. The simulation results show the driving forces during the charging and discharging process, where there is a variation for the angles of the domain walls from 180° to 90° (and then an increase to 135°), which are the external electric field and domain wall evolution, respectively. As for the phase states, there is a transformation between the orthorhombic and rhombohedral phases which can't be explained by the traditional polarization switching theory. This work provides a reasonable understanding of the alternating current field effect, which is essential in information and energy storage. [ABSTRACT FROM AUTHOR]

Summary: This article investigates the tracking control problem for a kind of chained‐form nonholonomic systems in the presence of unknown time‐varying disturbances and full‐state constraints. First, a finite‐time tracking controller is constructed to drive the action of relay switching, which converts the whole control system into two design stages. In order to handle with the predefined asymmetric state constraints, the original tracking error system is turned into an unconstrained system on the basis of state‐dependent function (SDF) function transformations. In this framework, an adaptive tracking control strategy is proposed by means of backstepping and dynamic surface control. Correspondingly, another tracking control law is also constructed to assure the stability of the tracking error system before the action of switching. The theoretical analysis of stability indicates that the proposed tracking control scheme can guarantee that the output state tracking errors converge to zero and the desired state constraints are not violated. At the same time, all the closed‐loop system signals maintain bounded in entire control process. Finally, the validity of the presented tracking control algorithm is demonstrated by simulation and experiment results. [ABSTRACT FROM AUTHOR]

Twitter has become a popular means of communication used in a variety of fields. This widely used platform has an impact on the way people express themselves and is changing language usage worldwide at an unprecedented pace. This article investigates the reasons for the use of French–English language mixing among French users on Twitter using a topic analysis approach. This analysis draws on Gumperz's theory of conversational switching. In order to collect tweets at a large scale, the data were collected in R using the rtweet package. A total of nine topic categories were identified and analyzed in this article: entertainment, internet/social media, events/community, politics/news, sports, sex/pornography, innovation/technology, fashion/makeup, and business. This study finds that entertainment is the most frequent topic discussed on Twitter. English words, such as trailer, spoil, and live are found in the data. This study enables a deeper understanding of users' linguistic behavior online, and offers insights into future trends in intercultural and cross-language exchanges. [ABSTRACT FROM AUTHOR]

In this work, we propose a context-aware switching of routing protocol scheme for specific application requirements of IoT in real-time using a softwaredefined networking controller in wireless sensor networks. The work planned has two stages i) Selection of suitable routing protocol (RP) for given IoT applications using higher cognitive process and ii) Deployment of the corresponding routing protocol. We use the supervised learning-regression method for classification of the routing protocol while considering the network parameters like stability, path delay, energy utilization, and throughput. The chosen routing protocol will be set in the sensor network using a software-defined networking controller in an exceedingly flexible manner during the second stage. Extensive simulation has been done and results are evaluated to point out the strength of the proposed work, while dynamically varying the specific requirements of IoT applications. We observe that the work proposed is path-breaking the prevailing methods, where a specific routing protocol is employed throughout the period of time. It's clearly shown that the proposed, Low-cost Context-Aware Protocol Switching (LCAPS) scheme is efficient in improving the performance of the sensor network and also meets the specific application requirements of IoT by using Software-Defined Wireless Sensor Networks SDWSNs. [ABSTRACT FROM AUTHOR]