Partial State Research Articles

Selective Reflection Control: Distributed IRS-Aided Communication With Partial Channel State Information

Intelligent reflecting surfaces (IRSs) enhance the robustness of wireless transmissions against shielding. However, addressing channel-estimation overheads caused by the large number of IRS elements remains a major challenge. In particular, these overheads increase proportionately with an increase in the number of IRS elements, thereby making it difficult to handle multiple IRSs. Therefore, we investigate a passive beamforming method with partial channel state information (CSI) in distributed IRS communication systems called selective reflection control (SRC). Specifically, the proposed method determines the associations between the IRS and user equipment (UE) to obtain the CSI of the associated IRS-UE links. Simulations were conducted, and the obtained results confirm that the proposed method based on SRC outperforms the benchmark method in terms of the user sum rate. Furthermore, the proposed method realizes robust transmissions against shielding owing to appropriate IRS–UE associations. Therefore, the proposed SRC achieves better communication performance with less channel estimation overheads, which is expected to accelerate large-scale IRS deployment.

Numerical analysis of partial impact forces of offshore submerged floating tunnel encountered submarine slide hazards

Submerged floating tunnels (SFT) provide novel and practical solutions for cross-sea transportation. However, the operating environment of undersea infrastructures is complex. Easily triggered and widespread hazards, particularly submarine slides, may cause devastating damage to submerged floating tunnels. In this study, the forces caused by a submarine slide mass impacting a tunnel structure and the effect of the slide mass thickness on these forces were determined. A computational fluid dynamics (CFD) approach was employed to analyse the submarine slide-tunnel interaction, covering Reynolds numbers of 0.36–208. There is a significant difference between impact forces under the partial impact state (i.e., the thickness of slide mass is not enough to flood a tunnel structure) and the flooded impact state (i.e., the slide flow reaches symmetrical on the upper and lower sides of the tunnel). The effect of the slide mass thickness on the impact forces is limited to a well-defined range of approximately −1.5–8.0 times the tunnel diameter (considering the tunnel bottom as 0) for instantaneous impact forces and −0.5–4.0 times the tunnel diameter for continuous impact forces. An evaluation approach for determining the forces for partial submarine slide-tunnel impact is proposed.

Safe reinforcement learning for discrete-time fully cooperative games with partial state and control constraints using control barrier functions

In this paper, a novel safe reinforcement learning is proposed for fully cooperative games of discrete-time multi-player systems with partial state and control constraints. The fully cooperative game is a special case of the nonzero-sum games where all players cooperate to accomplish the common task. However, there are few works for fully cooperative game issues of discrete-time systems with partial state and control constraints. The issue is addressed by our algorithm based on the constrained value iteration framework using the measured data along the system trajectories, and the Nash equilibrium of the constrained fully cooperative game is achieved. Compared to previous methods for fully cooperative game issues, neither the accurate system dynamics nor the initial admissible control policies are required via the algorithm. Meanwhile, the discrete-time exponential control barrier functions are adopted to address the issue of state constraints. Moreover, the convergence of the proposed algorithm is proven in theory. Then, the system dynamics, the control policies and the value function are approximated by the three-layer neural networks, respectively. Finally, two experiments are presented to demonstrate the safety and effectiveness of the proposed algorithm.

Asynchronous H[formula omitted] filtering for semi-Markov jump T-S fuzzy systems within partial state delay and deception attack: Applied to aircraft-pilot state estimation

This article addresses an asynchronous filter design problem within partial state delay and deception attack for a class of discrete-time semi-Markov jump Takagi-Sugeno (T-S) systems which can describe estimation process for human pilot cognitive property. First, the emission probability, which relates to system mode and filtering mode, is introduced to consider the system process with asynchronously observation scheme. Second, state delay-independent condition and state delay-dependent condition designed within state delay boundary are proposed under the H∞ performance index γ. Third, the system output signal under deception attack is adopted as the information interference during the transmitted filter process. Through the Lyapunov-Krasovskii approach, stability of the proposed filtering scheme that is mode dependent can be guaranteed. Moreover, the filtering mode is also dynamically changed according to the prescribed asynchronous formula. A numerical example considered for aircraft-pilot state estimation is used to demonstrate the effectiveness and applicability of our proposed filtering method by obtaining the minimum γ. Experiments show that filter could play a better role in advancing signal estimation in aircraft-pilot state estimation scenario with properties like state delay and deception attack. Also, it contributes to modelling the fully human pilot cognitive decision-making in a human-computer interaction scenario.

Force-induced wrapping phase transition in activated cellular uptake

Intracellular pathogens, including all viruses and many bacteria, enter a host cell through either passive endocytosis or active self-propulsion. Though the cellular uptake of passive particles via endocytic process has been studied extensively, little work has been done on the active entry of self-propelled pathogens, such as Listeria monocytogenes. Here, we present a theoretical model to investigate the adhesive wrapping of a self-propelled particle by a plasma membrane, and find a type of first-order wrapping transition from a small partial wrapping state to a large partial wrapping state triggered by the active force. The phase diagram displays more complex behaviors compared with the passive wrapping mediated merely by adhesion. We also find that a tubular protrusion can be formed if the active force exceeds a force barrier. These results may provide a useful guidance to the study of activity-driven cellular entry of active particles into cells.

Exponential Stability of Switched Neural Networks with Partial State Reset and Time-Varying Delays

This paper mainly investigates the exponential stability of switched neural networks (SNNs) with partial state reset and time-varying delays, in which partial state reset means that only a fraction of the states can be reset at each switching instant. Moreover, both stable and unstable subsystems are also taken into account and therefore, switched systems under consideration can take several switched systems as special cases. The comparison principle, the Halanay-like inequality, and the time-dependent switched Lyapunov function approach are used to obtain sufficient conditions to ensure that the considered SNNs with delays and partial state reset are exponentially stable. Numerical examples are provided to demonstrate the reliability of the developed results.

Scattering cross sections in complex scaling method

We have investigated the scattering cross sections of the various potential systems. In thepresent study, not only the scattering cross sections but also the contributions of the resonance andcontinuum states were computed for partial states of two various systems.

Intermittent observer-based dissipative saturation control for Korteweg-de Vries-Burgers equation with stochastic noise and incomplete measurable information

In this paper, a (Q, S, R)-r˜-dissipative control rate based on intermittent observations is developed for the Korteweg-de Vries-Burgers equation (KdVB) with stochastic noise and incomplete measurable information. Different from the existing works, the measurement transmissions from the sensor to the controller and from the controller to the actuator are assumed to be imperfect (i.e., the phenomenon of data packet dropouts may occur intermittently), and an intermittent observer is proposed to track the part state of the equation rather than the existing traditional full-order Lebesgue observer. In addition, a (Q, S, R)-r˜-saturation dissipation index is selected to design a unified control for KdVB dynamics, which is more general than H∞ exponent. More importantly, the calculated (Q, S, R)-r˜-saturation dissipation performance is completed under the condition of partial state loss of KdVB, which has great research significance and value in practical engineering applications. Finally, an example is given to verify the effectiveness and superiority of the proposed method.

Radiation characteristics of detached divertor plasmas in W7-X

• Spatial distributions of line emissions from hydrocarbon and carbon have been measured in detached divertor plasma in W7-X. • Spatial distributions of line emissions from hydrogen molecules and atoms have been measured in detached divertor plasma in W7-X. • Hydrogen Balmer line ratios indicate that the detached plasma is in excitation or partial recombination state. • Electron pressure along flux tube in SOL drops significantly but not deeper due to the lack of volume recombination in detached divertor plasma. Detached divertor plasmas has been achieved by density ramp in W7-X. During the transition into detachment, the main divertor radiation region moves from the region close to the divertor targets to the region around LCFS. The typical spatial distributions of carbon and hydrogen Balmer lines in detached divertor plasma are presented. They show that the line emissions of CH produced by chemical sputtering is still strong close to the targets. The C I fills up the whole detached divertor plasma and its intensity increases when approaching the targets due to the dissociation from hydrocarbon and self-sputtering. The C II and C III are mainly located at around LCFS region. Meanwhile, the distribution of hydrogen Balmer lines is considerably flatter in detached divertor plasma. The Balmer line ratios indicate that the detached divertor plasma seems to be still in excitation or partial recombination state. This is consistent with the divertor Langmuir probe measurements which shows that the electron temperature near strike line is around 6 eV. Finally, the electron pressure at upstream and downstream position is measured and its ratio shows that the electron pressure drops significantly along the magnetic field lines. However, the pressure can not drop further due to the lack of the volume recombination in detached divertor plasma.

Global Stabilization for Stochastic Continuous Cascade Nonlinear Systems Subject to SISS Inverse Dynamics and Time-Delay: A Dynamic Gain Approach

This article is devoted to the global continuous control for stochastic low-order cascade nonlinear systems with time-varying delay and stochastic inverse dynamics. Compared with existing results, the nature of only continuous, but nonsmooth, is unfolded since the power of the stochastic cascade system is of low order; and all the traditional growth conditions on unknown drift and diffusion nonlinearities and local Lipschitz condition are quitted, which largely extends the scope of application. Combining with stochastic input-to-state stability, two new lemmas are developed with rigorous proofs to deal with uncertain nonlinear terms and unmeasurable stochastic inverse dynamics. A continuous control scheme consisting of a delay-independent partial state feedback controller and a serial of dynamic update laws is proposed to guarantee the globally asymptotical stability of the closed-loop system.

Hydrogen evolution reaction at lead/carbon porous electrodes studied by a novel electrochemical mass spectrometry set-up

Lead–acid batteries are robust, low-cost, and have a large power-to-weight ratio. Recently, small amounts of carbon-based materials with a high surface area have been included in the Pb electrode as additives to improve the high-rate partial state of charge. However, carbon-based materials also enhance the hydrogen evolution reaction during the charging process at the negative active material (NAM), which is undesirable and dangerous. Therefore, in the current communication, a promising differential electrochemical mass spectrometry (DEMS) set-up suitable for studying the hydrogen evolution reaction (HER) at technical NAM electrodes in lead–acid batteries (LABs) is reported for the first time.

Decentralized Time-Delay Control Using Partial Variables With Measurable States for a Class of Interconnected Systems With Time Delays.

This article deals with the problems of stability and control of the interconnected system (IS) with unknown time-varying delays via decentralized time-delay control using partial variables with measurable states. First, the model of the IS with time delays is established, and the relevant control scheme is proposed. The control scheme just needs to control all or partial state variables corresponding to the elements on the main diagonal of the gain matrices, which can reduce the control cost and improve the flexibility of control. In addition, there are no additional restrictions in the process of designing the controller. Second, relevant lemmas are derived. The exponential boundedness and stability analysis of the IS with time delays are presented, respectively, by stability theory, and related results are derived. Meanwhile, the stability domain of the IS is estimated. Besides, the obtained results can also be used for many practical systems, such as the interconnected power system, the multislave teleoperation systems, the brushless dc motor (BLDCM) system, and the chaotic system. Finally, the effectiveness and application of the obtained results are verified by several examples.

Guaranteed performance impulsive tracking control of multi-agents systems under discrete-time deception attacks

This paper is concerned with the impulsive consensus tracking problem of Lipschitz nonlinear multi-agent systems subject to deception attacks. The proposed distributed impulsive tracking algorithm allows only partial state variables of every agent to be governed by consensus impulses. The considered deception attacks are supposed to take place in the controller–actuator channel, and can be modelled by a set of Bernoulli processes. By considering the discrete-time deception signal as bounded external disturbance, the consensus tracking problem reduces to the exponential input-to-state stable (EISS) problem of the tracking error system. The EISS-gain is used as an assessment index in measuring the capacity of consensus control laws for attenuating attacks. Specifically, a novel EISS analysis method combined with the use of a weighted discontinuous Lyapunov function is proposed to establish the consensus tracking criterion. A convex optimization problem with linear matrix inequalities-based constraints is formulated to design the guaranteed performance distributed impulsive controller, which makes the EISS-gain as small as possible. Two illustrated examples quantify the effectiveness of the proposed analysis and design approach.

First-Principles Calculations to Investigate the Effect of Van der Waals Interactions on the Crystal and Electronic Structures of Tin-Based 0D Hybrid Perovskites

The electronic structures of four tin-based 0D hybrid perovskites ((NH3(CH2)2C6H5)2[SnCl6], (C6H10N2)[SnCl6], (C9H14N)2[SnCl6], and (C8H12N)2[SnCl6]) were determined by the DFT method employing the pseudopotential plane wave as implemented in the CASTEP code, and the first transition in each compound has been investigated based on the partial density states and dielectric function. According to the structural properties, incorporating organic cations with the appropriate structure, shape, and strong H-bonding functionality into hybrid perovskite crystals is very beneficial for preventing ion migration and thus enhances the efficiency of hybrid perovskite-based devices. Based on those properties employing the DFT+D method for the dispersion force, the effect of Van der Waals interaction on electronic structure was explained based on the nature of the first electronic transition. The similarity between the experimental and optimized structure was investigated by using a Bilbao crystallographic server. The study of optical properties shows that the Van der Waals interactions have a slight effect on the energy level of the curves. However, the profiles of curves are conserved. The absorption curves of the researched compounds are elaborated.

Study of bound and resonance states of 11Be in breakup reaction

We investigate the Coulomb breakup of the 11 Be halo nuclei on a lead target within non-perturbative time-dependent approach in a wide range of beam energy (5–70 MeV/nucleon) including the low-lying resonances in different partial and spin states of 11 Be. We have found considerable contribution of the low-lying resonances ( 5/2+ , 3/2− and 3/2+ ) to the breakup cross section of 11 Be. The obtained results are in good agreement with existing experimental data at 69 MeV/nucleon. The developed computational scheme opens new possibilities in investigation of Coulomb, as well as nuclear, breakup of other halo nuclei on heavy, as well as, light targets.

The Effect of the Displacement Amplitude on the Fretting Wear of GCr15 Steel with a TiC Coating.

In the present paper, the effect of mechanical ball milling time on the fretting wear of GCr15 steel balls at different displacement amplitudes is investigated. TiC powder coating was fabricated on the surface of GCr15 steel balls using various process times, and the fretting wear tests were conducted on an AISI 52100 steel disk with the applied force of 80 N. Additionally, various displacement amplitudes (10 μm, 20 μm, and 60 μm) were selected. Specimen attributes and wear scars were characterized using an inverted metallographic microscope, a microhardness tester, an X-ray diffractometry analyzer, a white light interferometer, and a scanning electron microscope. The results showed that thick and continuous coatings could be obtained at the milling time of 18 h. The specimens processed for a longer milling time demonstrated better fretting wear resistance, which we attribute to higher microhardness of the surface layer. The coefficient of friction and wear volume of specimens at each different displacement amplitude significantly decreased with increasing milling time. As the displacement amplitude increased, the three fretting states were: partial slip coordinated by elastic deformation; partial slip state coordinated by plastic deformation; and gross slip condition. Our observations indicate that mechanical ball milling could be an efficient approach to improve the fretting wear resistance of GCr15 steel balls.

Least-cost transition sequence estimation in labelled time Petri net systems with unobservable transitions

This paper presents an approach to solve the least-cost transition sequences estimation problem in labelled time Petri net (LTPN) systems with unobservable transitions. Particularly, the considered LTPN system is bounded, in which each transition has a nonnegative cost and is labelled as either observable or unobservable. We first introduce a graph, called a segmented modified state class graph (SMSCG), that is a compact representation of the partial state space of an LTPN system. Based on the SMSCG and an observed time-label sequence, a method to estimate logic consistent transition sequences is proposed. By exploiting the transitions-related timing constraints in SMSCGs, a procedure for determining which logic consistent transition sequences are timing consistent with the observed time-label sequence and a given time is reported. Finally, we develop an algorithm to perform the estimation of least-cost transition sequences.

Vapor condensation on micropillar structured surface with lattice Boltzmann method

Pure vapor condensation process and heat transfer on micropillar structured surfaces with various wettabilities are simulated numerically based on an improved three-dimensional phase-change lattice Boltzmann method (LBM). Condensed droplet dynamic behaviors containing nucleation, growth and departure are mainly explored. Two preferable droplet nucleation sites are detected successfully: at the corner between micropillar sides and subcooled substrate, and at the center of substrate. The effects of contact angle, micropillar spacing and height on droplet nucleation time, departure diameter and departure frequency are investigated quantitatively. Results indicate that as the contact angle increases, nucleation of condensate is delayed, while the departure diameter is reduced and departure frequency is increased. The increase in micropillar spacing, height and contact angle changes droplet from Wenzel state to partial wetting state. Moreover, it is also shown that the highest temperature and maximum local heat flux appear at the three-phase contact line. Despite the very complex roles of micropillar structures and wettability on condensation heat transfer, an optimal heat transfer surface with configurations of contact angle of 90°, micropillar spacing of 12 and height of 18 is presented. This study provides a fundamental understanding in regards to vapor condensation on microscale structured surface from numerical view.

Harmonic Compensation via Grid-Tied Three-Phase Inverter with Variable Structure I&I Observer-Based Control Scheme

The power inverter topologies are indispensable devices to incorporate distributed generation schemes, like photovoltaic energy sources into the AC main. The nonlinear behavior of the power inverter draws a challenge when it comes to their control policy, rendering linear control methods often inadequate for the application. The control complexity can be further increased by the LCL filters, which are the preferred way to mitigate the current ripple caused by the inverter switching. This paper presents a robust variable structure control for a three-phase grid-tied inverter with an LCL filter. As well to the benefits of the sliding mode control (SMC), which is one of the control methods applied by power converters founded in literature, the proposed control scheme features a novel partial state observer based on the immersion and invariance technique, which thanks to its inherent robustness and speed of convergence is adequate for this application. This observer eliminates the need for physical current sensors, decreasing the overall cost and size, as well as probable sources of noise. The proposed controller is meant for a three-phase grid-tied inverter to inject active power to the grid while harmonics generated by nonlinear loads are compensated. The simulation results prove the effectiveness of the proposed method by compensating for current harmonics produced by the nonlinear loads and maintaining a low total harmonic distortion as recommended by the STD-IEEE519-2014, regardless of whether the system provides active power or not.

Critical Mass and Critical Representation

Women’s critical mass helps change male-dominated cultures and promote women’s career advancement, but its effects vary across organizational domains and are sometimes constrained by persistent gender structures and power relationships inside and outside workplaces. By analyzing a nationally representative sample of China’s private companies, this study examines how women’s representation, not only in sheer numbers but also in certain powerful positions (e.g., owners or shareholders), affects women’s leadership potential. Despite evidence of positive trends in women’s leadership in the Chinese corporate context, women’s representation has been hamstrung by institutional legacies (e.g., partial state ownership). The effects of women’s representation also differ by industrial sector. Women are more likely to reach senior management in low-tech, labor-intensive industries, where women dominate the workforce, than in industries with higher technological demands, where men dominate the workforce. Women owners or shareholders matter more for the promotion of women CEOs in higher-tech companies. Our study contributes to the literature on gendered organizations by offering insights on how transitional institutional forces and large industrial systems converge and interact with women’s representation to affect their upward occupational trajectory in developing contexts.