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We present a novel numerical approach for solving nonlinear constrained optimal control problems (NCOCPs). Instead of directly solving the NCOCPs, we start by linearizing the constraints and dynamic system, which results in a sequence of sub-problems. For each sub-problem, we use finite number of Chebyshev polynomials to estimate the control and state vectors. To eliminate the errors at non-collocation points caused by conventional collocation methods, we additionally estimate the coefficient functions involved in the linear constraints and dynamic system by Chebyshev polynomials. By leveraging the characteristics of Chebyshev polynomials, the approximate sub-problem is changed into an equivalent nonlinear optimization problem with linear equality constraints. Consequently, any feasible point of the approximate sub-problem will satisfy the constraints and dynamic system throughout the entire time scale. To validate the efficacy of the new method, we solve three examples and assess the accuracy of the method through the computation of its approximation error. Numerical results obtained show that our approach achieves lower approximation error when compared to the Chebyshev pseudo-spectral method. The proposed method is particularly suitable for scenarios that require high-precision approximation, such as aerospace and precision instrument production. • A sequence of sub-problems is constructed by linearizing the dynamic system and constraints. • Each sub-problem can be transformed into an equivalent nonlinear optimization problem with linear equality constraints through Chebyshev polynomials. • Any feasible solution of the approximate sub-problem will satisfy its dynamic system and constraints over the entire time horizon. • Global convergence of the proposed method is established. [ABSTRACT FROM AUTHOR]

This study addresses the asynchronous control problem for a semi-Markov switching system in the presence of singular perturbation and an improved triggering protocol. To decrease the occupation of network resources, an improved protocol is skillfully established by adopting two auxiliary offset variables. Unlike the existing protocols, the established improved protocol is capable of arranging information transmission with more degrees of freedom, thereby reducing the communication frequency and maintaining control performance. Apart from the reported hidden Markov model, a nonhomogeneous hidden semi-Markov model is used to handle the mode mismatch between the systems and controllers. Benefiting from Lyapunov techniques, parameter-dependent sufficient conditions are devised to ensure a stochastically stable subject to a predetermined performance. Finally, the validity and practicability of the theoretical results are verified via a numerical example and a tunnel diode circuit model. • A dynamic event-triggered mechanism is proposed, whose threshold parameter changes with the resulting states. • The nonhomogeneous Markov switching actuator fault is applied, whose transition probabilities are time-varying and characterized in a polytope set. • Several singularly perturbed parameter-independent sufficient conditions are achieved. [ABSTRACT FROM AUTHOR]

The potential of microplastics to carry coexisting pollutants and contribute to combined pollution is a significant health concern. Here we investigate the presence of antibiotic resistance genes (ARGs) in both intracellular ARGs (iARGs) and extracellular ARGs (eARGs) forms, on microplastics collected from the coastal waters of the East China Sea. Our findings revealed that both iARGs and eARGs were enriched on microplastics. Specifically, 6- to 55-fold enrichment of iARGs was found on microplastics, while eARGs were more significantly enriched (5–140 fold). 16s rDNA analysis revealed that microplastics harbored a more diverse microbial community, particularly opportunistic pathogens, compared to surrounding seawater. This contributes to more correlations between bacterial genera and ARGs on microplastics than in sea water. Molecular ecological network analysis indicated that total nitrogen and ammonia were primary determinants of ARG and microbial enrichment on microplastics. This study provides implications for understanding the combined pollution of microplastics and ARGs. • The concentration of iARGs on microplastics is 6–55 fold of those in seawater. • eARGs are more significantly enriched on microplastics than iARGs. • Microplastics harbored a higher abundance of opportunistic pathogens than in seawater. • Total nitrogen and ammonia were primary factors of ARG enrichment on microplastics. [ABSTRACT FROM AUTHOR]

• Configural and featural face processing bias are modulated by the race of observers and the race of face stimuli. • Configural face processing elicited a larger P1 under the attended own-race face condition for Chinese participants. • Featural face processing elicited a larger P1 under the attended own-race face condition for Westerners. • Featural face processing elicited a larger P2 under the attended own-race face condition for Chinese participants. • Configural face processing elicited a larger P2 under the attended own-race face condition for Westerners. Previous research suggests that East Asians pay more attention than Caucasian Westerners to configural information in faces, while the latter group pays more attention to featural information. However, it is unclear whether this cultural variation in attention produces a different time course of the processing bias for configural and featural information. This was examined using event-related potentials in a spatial attention paradigm. Chinese and Westerners were instructed to attend to the locations of two face images or houses. Although the race-related difference was absent in behavioral performance and N170 component, Chinese participants exhibited a configural processing bias on P1 component in the case of both own- and other-race faces and a featural processing bias on P2 component for own-race faces. In contrast, Westerners exhibited a featural processing bias for own-race faces and a configural processing bias for other-race faces on P1 component, whereas a configural processing bias was observed on P2 component for both own- and other-race faces. These results demonstrate that there are important differences between East Asians and Westerners in their relative preferences for configural versus featural processing of own-race faces, but not other-race faces. The relative roles of configural and featural information processing for faces are thus dependent on both who is looking (the culture or race of the observer) and what they are looking at (the race of the face): Easterners enjoy an early global/configural processing bias and a late local/featural processing bias for own-race faces, while Westerners benefit from an early local/featural processing bias and a late global/configural processing bias for own-race faces; both of the groups have an early and late global/configural processing bias for other-race faces. [ABSTRACT FROM AUTHOR]

Highlights • We studied brain activity in different stages of a high-demanding working memory task. • Results show constant activation in the dorsal anterior cingulate cortex and anterior insular. • These areas form the neural basis of a core control network of CES. • Dynamic configuration of multiple downstream systems indicates the regulation mechanism of CES. Abstract The central executive system (CES) may be the most fundamental yet least understood component of working memory. There is an ongoing debate about which brain regions underlie the top-down regulation of CES during working memory tasks. The neural substrates and regulatory mechanisms of CES remain controversial partly because few previous studies have been focused on comprehensive activation and deactivation joint analysis on all systems involved in all working memory stages, which have shown increasing importance in depicting the neural configuration of working memory. To address these questions, we conducted a functional magnetic resonance imaging study using a comprehensive activation-deactivation-behavior joint analysis to examine the dynamics of a set of cortical systems in healthy subjects performing a modified Sternberg working memory task which was designed to push the subjects to their limit in working memory and to introduce strong demands for regulation by CES. We assessed brain activity during various working memory stages using general linear model and single trial-stage estimation, and examined the relationship between the single trial-stage activity and behavioral performance. We identified constant activation in the dorsal anterior cingulate cortex and anterior insula in all working memory stages and its relationship with performance, which indicate the CES's neural basis. We also identified dynamic configuration of multiple downstream systems in different working memory stages, which indicates the regulation mechanism of CES. [ABSTRACT FROM AUTHOR]

Face recognition requires both configural and featural processing. Configural face processing is more dependent on the right hemisphere, whereas featural face processing is more dependent on the left hemisphere. The ERP components sensitive to configural and featural face processing were found on P1 and P2, respectively. However, whether lateralized processing is independent of or interacts with the temporal sequence of configural and featural face processing is unclear. To prevent potentially confounding physical stimuli differences between configural and featural face processing from affecting the ERP components, a spatial attention paradigm was employed in which the participants were instructed to attend to the face location (the attended face condition) or the house location (the unattended face condition). The interaction effect of attention, face processing type and hemisphere on the P1 and P2 components indicates that the different mechanisms of configural and featural face processing are a function of spatial attention. Specifically, under the attended face condition, the posterior P1 (approximately 100 ms) for configural face processing was larger than that for featural face processing in the right hemisphere, whereas the P2 (approximately 220 ms) for featural face processing was larger than that for configural face processing in the left hemisphere. In contrast, under the unattended face condition, the P1 for featural face processing was larger than that for configural face processing in the left hemisphere, whereas the P2 for configural face processing was larger than that for featural face processing in the right hemisphere. Therefore, configural and featural processing involve different neural mechanisms, and more importantly, the time course of hemispheric asymmetry in configural and featural face processing is differentially modulated by spatial attention. [ABSTRACT FROM AUTHOR]

Face recognition theories suggest that our brains process invariant (e.g., gender) and changeable (e.g., emotion) facial dimensions separately. To investigate whether these two dimensions are processed in different time courses, we analyzed the selection negativity (SN, an event-related potential component reflecting attentional modulation) elicited by face gender and emotion during a feature selective attention task. Participants were instructed to attend to a combination of face emotion and gender attributes in Experiment 1 (bi-dimensional task) and to either face emotion or gender in Experiment 2 (uni-dimensional task). The results revealed that face emotion did not elicit a substantial SN, whereas face gender consistently generated a substantial SN in both experiments. These results suggest that face gender is more sensitive to feature-selective attention and that face emotion is encoded relatively automatically on SN, implying the existence of different underlying processing mechanisms for invariant and changeable facial dimensions. [ABSTRACT FROM AUTHOR]

This paper addresses the problem of event-triggered H ∞ control for a class of T–S fuzzy nonlinear systems. An improved event-triggered scheme (ETS) characterized by discrete sampling is proposed, where the time-derivative of the membership function is not required. To get conservative conditions, the deviation bound of asynchronous normalized membership functions is considered. By utilizing the non-quadratic fuzzy line-integral Lyapunov functions and a free-matrix-based integral inequality, novel criteria for stabilization analysis of T–S fuzzy nonlinear systems are established. Finally, a truck–trailer system is provided to show the effectiveness of the proposed theories. [ABSTRACT FROM AUTHOR]

This paper investigates the problem of finite-time event-triggered H ∞ boundedness for network-based Markovian jump nonlinear system. An improved model is introduced in terms of network-induced delay. By synthesizing the newly event-triggering conditions, the finite-time H ∞ boundedness for networked Markovian jump nonlinear systems are guaranteed. At last, a numerical example is given to illustrate the effectiveness of proposed theoretical results. [ABSTRACT FROM AUTHOR]

This paper studies the finite-time stochastic contractive boundedness problem for a class of Markovian jump linear systems subject to input constraints. First of all, by employing exogenous disturbance, two novel concepts, namely finite-time stochastic contractive stability (FTSCS) and finite-time stochastic contractive boundedness (FTSCB) are introduced. Secondly, a relaxation scheme for incomplete (i.e., partly known, unknown, and uncertain) transition probability descriptions is introduced. Then, two kinds of design methodology of observer-based controllers are proposed. All the design conditions are established by employing a set of linear matrix inequalities (LMIs). At last, numerical examples are given to demonstrate the effectiveness of the proposed approach. [ABSTRACT FROM AUTHOR]