State Of System Research Articles

THE PROFESSIONAL LANDSCAPE OF POLISH TEACHERS AS PRESERVED IN THEIR DIARIES FROM THE FIRST MONTHS OF THE COVID-19 PANDEMIC

The article presents the conclusions formulated on the basis of a qualitative analysis of diaries submitted by Polish teachers in response to the competition conducted in the years 2020-2021 by the Institute of Social Economy of the Warsaw School of Economics. The analysis of the diaries made it possible to answer questions about the condition of not only the teachers themselves, but also, and above all, about the emerging picture of the state of the Polish education system. The difficult times and new circumstances of school functioning during the pandemic highlighted the importance and essence of the teacher profession. However, these experiences also revealed the weaknesses of the education system, forcing us to look at the extent to which teachers are able to adequately recognize the situation of their activities, to what extent they have the ability to recognize the essence of “what is good and right”, how their awareness of their socio-professional role is shaped, what importance they attach to their work and what are their abilities to overcome extraordinary difficulties.The COVID-19 pandemic has created unprecedented challenges for education that have resulted in profound changes in the way we think about school and its environment and about the work and professional development of teachers.

РОЛЬ ИММУННОГО ОТВЕТА В РАЗВИТИИ ГИПОКСИЧЕСКИХ ОСЛОЖНЕНИЙ РЕСПИРАТОРНЫХ ИНФЕКЦИЙ НИЖНИХ ДЫХАТЕЛЬНЫХ ПУТЕЙ У ДЕТЕЙ

Pneumonia is one of the most common severe infectious diseases in pediatric practice. Hypoxia is common in children with pneumonia and is one of the main predictors of poor outcome. The role of the central link in the cellular response to hypoxia is played by the family of hypoxia-inducible factors (HIF). HIF-1α is the key regulator of both T- and B-lymphocyte functions. The processes of their maturation are accompanied by the formation of circular DNA fragments, TREC (T-cell Receptor Excision Circle) and KREC (Kappa-deleting Recombination Excision Circle). TREC and KREC are unable to replicate and serve as markers for naive lymphocyte production. In its turn, HIF-1α can be used as a marker for cellular hypoxia. The use of TREC and KREC in assessing the immune system in patients with various immunological and infectious pathologies has already been described. At the same time, HIF-1α has so far been little studied as yet. The purpose of this research was to analyze the scientific bibliographical data on the HIF-1α assessment as a marker for hypoxia as well as the quantitative level of TREC and KREC as markers for the adaptive immune response; to study the bibliographical sources on the effect of hypoxia on the immune response, including as part of lower respiratory tract infections. Methods used: bibliographical research in Scopus, PubMed and Google Scholar with keywords “TREC,” “KREC,” “HIF,” “hypoxia,” “pneumonia,” “immune response,” that was then followed by the search results’ systematization, analysis and synthesis. Results: the analysis of bibliographical sources had allowed the Authors to conclude that there is a possible close connection between acute hypoxia and the formation of an adequate immune response in infectious pathologies. Research in this area is still extremely scarce. At the same time, the prospects for this area determine the need for further fundamental and clinical research. Conclusion: it is of a great scientific and clinical interest to be able to non-invasively assess the degree of acute hypoxia during an ongoing infectious disease by examining urinary HIF-1α levels. Particularly promising is the assessment of the HIF-1α level not only as a regulator of tissue adaptation to acute hypoxia, but also as a modulator of the immune response. Taking into consideration the analyzed data, both TREC and KREC appear to be the optimal markers characterizing the functional state of the adaptive immune system.

Sustaining Situational Assessment in Electrical Network Power Control

Objective The aim of this study was to examine contributions to sustained situational assessment over an extended period in the context of electricity transmission control. Background The electricity industry is engaged in a period of unprecedented change in the transition to renewable sources of energy. Changes in the nature and function of electricity transmission risks a reduction in situational assessment as network controllers place increased reliance on advanced technology to identify and diagnose changes in the system state. Method Transmission network controllers from three organisations completed an assessment of their situational assessment on two occasions, one year apart. Results Multiple regression revealed a statistically significant model in which the variance in Year 2 was predicted by a combination of performance in Year 1, the recency of formal training, and the extent to which controllers perceived their job as exciting. No relationship was evident for years of experience as a network controller. Conclusion The results suggest that a combination of recent formal training and perceptions of job excitement may have implications in maintaining the capacity for situational assessment over an extended period in the context of electricity network control. Application The outcomes of the present study suggest that changes in situational assessment can be monitored and that strategies, including formal training and job design, may sustain situational assessment over an extended period in advanced technology settings.

Correlated qubit coherences stimulated by thermal energy

Abstract Quantum coherence, the ability of a system to be in a quantum superposition of pure states, is a distinct feature of quantum mechanics that has no direct analog in classical mechanics.
 Quantum states that possess coherence efficiently outperform their classical counterparts in fundamental science and practical applications, including quantum metrology, computation, and simulation. Generation of coherence without the need to employ strong classical drives remains a challenging and not yet experimentally explored task. Beyond individual thermally-induced coherences already proposed for different experiments, correlated quantum coherences of multiple qubits represent a new target. We prove that correlated qubit coherence emerges thermally stimulated from incoherent states in hybrid superconducting and solid-state systems comprising non-interacting qubits coupled only via Dicke-type interaction to a shared thermal mechanical oscillator, exhibits coherences beyond the Tavis-Cummings coupling and, moreover, can be advantageous in quantum sensing.

Lattice holography on a quantum computer

We explore the potential application of quantum computers to the examination of lattice holography, which extends to the strongly coupled bulk theory regime. With adiabatic evolution, we compute the ground state of a spin system on a (2+1)-dimensional hyperbolic lattice, and measure the spin-spin correlation function on the boundary. Notably, we observe that with achievable resources for coming quantum devices, the correlation function demonstrates an approximate scale-invariant behavior, aligning with the pivotal theoretical predictions of the anti–de Sitter/conformal field theory correspondence. Published by the American Physical Society 2024

Investigation of a Method for Identifying Unbalanced States in Multi-Disk Rotor Systems: Analysis of Axis Motion Trajectory Features

The operational state of a rotor system directly affects its working efficiency, and the axis trajectory can accurately characterize this state. Therefore, a method for extracting axis motion trajectory characteristics based on distance sequence representation is established. First, the axis trajectory sample signal is constructed from the original vibration displacement signal. Singular value decomposition (SVD) is performed on the sample signal to obtain effective components, resulting in a purified and denoised axis motion trajectory signal. Next, the axis motion trajectory signal is centralized and normalized. Feature extraction is then performed on the axis motion trajectory signal. Based on the different curvatures of various regions in the axis motion trajectory graph, data points are adaptively selected. The distances between the selected data points and a unique fixed point are calculated in the two-dimensional plane, resulting in a feature signal that characterizes the axis motion trajectory graph. This completes the extraction of the axis motion trajectory characteristics. Different rotational speeds, additional weights, and changes in rotor arrangement types are applied to a multi-disk rotor test rig to obtain measured data for various unbalanced states, validating this method. The results show that this method effectively characterizes the axis motion trajectory with strong generality.

Experimental study on the rupture behaviors of orthogonal faults: effects of stress state and rupture initiation location

Summary Fault rupture dynamics is expected to be significantly affected by the geometry of fault system, especially for orthogonal faults. However, the rupture behaviors of orthogonal faults especially the coseismic interactions are far from fully understood. Here, we present experimental results from a series of laboratory earthquakes to elucidate the effect of the stress state and initiation location on the rupture behaviors of orthogonal faults. Our results reveal a phase diagram of rupture behaviors of orthogonal faults, which is collectively controlled by stress state and rupture initiation location. For events initiating from the main fault, the rupture cannot jump to the branch, which may be due to the clamping effect or the inhibited shear stress accumulation on the branch. On the contrary, events initiating from the branch can persistently trigger ruptures of the main fault. This difference highlights the directional effect associated with the rupture of orthogonal faults. Further, the rupture length of triggered ruptures on the main fault is controlled by the stress state of the fault system. With the increase of the ratio between the shear stress and normal stress, the rupture length of the main fault increases. Our results reproduce the rupture behaviors of orthogonal faults, which may provide insights into the rupture characteristics of natural earthquakes.

Coherent feedback ground state cooling of the mechanical resonator in quadratic optomechanical system assisted by an atomic ensemble

We propose a scheme for cooling a mechanical resonator to its ground state in a quadratic optomechanical system, assisted by an atomic ensemble in the unresolved sideband regime. The system features an auxiliary cavity directly coupled to an optical cavity, with a portion of the optical cavity’s output field being fed back through an asymmetric beam splitter. Utilizing quantum Langevin and master equations, we derive the optical fluctuation spectrum, the cooling rate, and the mean phonon number of the mechanical resonator. Our results demonstrate that the feedback mechanism substantially enhances the cooling rate. Furthermore, under optimal cooling conditions, the mechanical resonator achieves ground state cooling even with weaker optomechanical coupling strengths and higher auxiliary cavity dissipation rates, thereby mitigating the experimental constraints associated with these parameters. Additionally, we provide the feasible ranges for optomechanical coupling strength and atomic decay rates. Our findings suggest promising avenues for quantum manipulation in nonlinear systems and its applications in macroscopic optical devices.

Improving Distribution System State Estimation by Including Volt-Var Control Information

Improving Distribution System State Estimation by Including Volt-Var Control Information

Estimation of real‐time reachable set on nonlinear time‐delay switched singular systems with state jump

AbstractThis article addresses the real‐time reachable set problem on nonlinear time‐delay switched singular systems with state jump, which is subject to initial state and peak‐bound disturbance. Initially, based on the system state decomposition method, a state jump lemma is proposed, which combines the nonlinear function and the system state at the switching instant. Then, a real‐time bounded lemma is developed, premised on using the idea of average dwell‐time and analyzing subinterval function changes. Afterwards, the sufficient conditions for estimating the real‐time and nonreal‐time reachable set are established, which ensures that the reachable state of system can be restricted within a real‐time or nonreal‐time closed set. Finally, simulation results of the typical Direct Current boost chopper are performed to exhibit the effectiveness of the devised estimation scheme for the real‐time reachable set of system.

Adaptive Visual Control for Robotic Manipulators with Consideration of Rigid-Body Dynamics and Joint-Motor Dynamics

A novel cascade visual control scheme is proposed to tailor for electrically driven robotic manipulators that operate under kinematic and dynamic uncertainties, utilizing an uncalibrated stationary camera. The proposed control approach incorporates adaptive weight radial basis function neural networks (RBFNNs) to learn the behaviors of the uncertain dynamics of the robot and the joint actuators. The controllers are designed to nullify the approximation error and mitigate unknown disturbances through an integrated robust adaptive mechanism. A major advantage of the proposed approach is that prior knowledge of the dynamics of the robotic manipulator and its actuator is no longer required. The controller autonomously assimilates the robot and actuator dynamics online, thereby obviating the need for fussy regression matrix derivation and advance dynamic measurement to establish the adaptive dynamic parameter update algorithm. The proposed scheme ensures closed-loop system stability, bounded system states, and the convergence of tracking errors to zero. Simulation results, employing a PUMA manipulator as a testbed, substantiate the viability of the proposed control policy.

Life prediction of lithium battery based on particle filter and BP neural network

Abstract This paper focuses on using Particle Filter (PF) and Back Propagation (BP) neural networks for RUL prediction. This fusion strategy uses particle filtering (PF) for battery system state estimation and prediction while considering various types of noise and uncertainties to assess the system state comprehensively. Furthermore, the strategy employs a BP neural network to learn and combine historical data patterns with particle filtering estimation, improving prediction accuracy and reliability. This study validates the proposed fusion method by comparing it with the original PF and BP prediction methods using Toyota Motor Corporation and Stanford University datasets. The experimental results demonstrate its superior performance and higher prediction accuracy.

Event-Triggered Adaptive Neural Control for MIMO Nonlinear Systems With Rate-Dependent Hysteresis and Full-State Constraints via Command Filter.

This article presents an event-triggered adaptive acrlong NN command-filtered control for a class of multi-input and multi-output (MIMO) nonlinear systems with unknown rate-dependent hysteresis in the actuator and the constraints on full states. The acrlong ETM is used to reduce the communication frequency between controller and actuator. The command filter technique is first employed to solve the dilemma between the nondifferentiable control signal at triggering instants and rate-dependent hysteresis input premise while avoiding the "explosion of complexity" problem. During the backstepping design, the barrier Lyapunov functions are utilized to guarantee that system states will stay in certain regions and the unknown nonlinear items are approximated by adaptive neural networks. The compensating signals are constructed to eliminate filtering errors. The estimates of unknown hysteresis parameters are updated by adaptive laws. The stability analysis is given and the effectiveness of the proposed method is verified by simulation.

Statistical Recognition of OAM States in Free-Space Optical System

Statistical Recognition of OAM States in Free-Space Optical System

Studying the State of the Autonomic Nervous System and Hemodynamics in the Liquidators of the Accident at the Chernobyl NPP

Studying the State of the Autonomic Nervous System and Hemodynamics in the Liquidators of the Accident at the Chernobyl NPP

Investigating the adsorption performance of agricultural greenhouses hazardous gases on Rh doped HfX2 (X=S, Se) monolayers through DFT for potential gas sensor applications

This study uses density functional theory to study the adsorption performance of agricultural greenhouses hazardous gases on Rh doped HfX2 (X=S, Se) monolayers. After multiple geometric optimizations, the most stable adsorption configuration was found. The results indicate that the adsorption energy of Rh doped HfX2 monolayers is very stable for adsorbing small molecule gases. The change in the total density of states of the adsorption system reveals the transfer and recombination of electrons during the adsorption process, and the partial density of states helps to understand the interactions between bonding atoms. Molecular orbital analysis shows that LUMO is mainly concentrated near Hf atoms, while HOMO is mainly concentrated near X atoms, Rh atom, and gases. By calculating the work function, the interaction strength and electron transfer mechanism between the adsorbent and the metal surface are revealed. In addition, the recovery time indicates that HfX2 and Rh-HfSe2 are excellent adsorbents for these four gases at room temperature, but when HfS2 operates at 473 K, it will be an efficient and excellent gas sensor for the four gases. Thus, Rh-HfS2 can be a feasible resistance sensing material for Cl2 and SO2. This DFT results provide a theoretical basis for potential gas sensor applications of Rh doped HfX2 (X=S, Se) monolayers, leading to the design and development of more efficient greenhouse gas identification sensor devices.

Unified monitoring and online maintenance technology of substation secondary equipment

Abstract To meet the needs of the promotion of “equipment ownership” and the implementation of a centralized monitoring mode in substations, a technical scheme of unified monitoring, online operation, and maintenance for secondary equipment in substations is proposed, considering the monitoring, operation, and maintenance requirements of secondary equipment such as protection devices and automation devices. A secondary equipment monitoring real-time gateway is arranged in Security Zone I. The comprehensive operation status data of various secondary equipment is collected, analyzed, processed, diagnosed, and applied through various apps, to realize heterogeneous access, on-demand deployment, and flexible expansion. The master station is designed with functions such as human-machine interaction and remote analysis for secondary device monitoring and operation. GSP, MQTT, and other service-oriented and message mechanism communication protocols are adopted between the substation and the master station to meet the diversified and easily expandable information exchange requirements. Through the factory test, it is verified that the scheme can realize the panoramic perception of the operation state of the secondary system and effectively improve the ability of abnormality diagnosis and processing.

Specificity of modeling the actuator for the deployment of transformable large-scale space structures

Abstract The creation of large-scale structures will be necessary for the development of information and transport space systems. Transformable systems form a distinct category of such space structures, designed based on automatic configuration changes. The transport and deployed operating states of transformable space systems can vary in dimensions by tens of times, with force actuators carrying out the deployment process. The optimal force actuator suitable for use in transformable space structures is an actuator comprising of active elements made of a titanium nickelide material with a shape memory effect, which has the ability to generate significant force, reliability, compactness, light weight and low power consumption. In the pursuit of developing large-scale transformable space systems, tremendous importance is placed on conducting full-scale experiments, which require costly equipment to be simulated in ground conditions. Therefore, an alternative option to verify the functionality of the large-scale transformable space system in development is through conducting a mathematical experiment utilizing the identifiable parameters of the developed computational models. Experimental and theoretical analyses of the active elements of the force actuator made of titanium nickelide material (1.5 mm diameter wire) have confirmed the fundamental possibility of creating a force actuator for opening large-scale transformable space structures.

Dynamic Event-Based Adaptive Fixed-Time Control for Uncertain Strict-Feedback Nonlinear Systems With State Constraints.

In this article, the event-triggered fixed-time tracking control is investigated for uncertain strict-feedback nonlinear systems involving state constraints. By employing the universal transformed function (UTF) and coordinate transformation techniques into backstepping design procedure, the proposed control scheme ensures that all states are constrained within the time-varying asymmetric boundaries, and meanwhile, the undesired feasibility condition existing in other constrained controllers can be removed elegantly. Different from the existing static event-triggered mechanism, a dynamic event-triggered mechanism (DETM) is devised via constructing a novel dynamic function, so that the communication burden from the controller to actuator is further alleviated. Furthermore, with the aid of adaptive neural network (NN) technique and generalized first-order filter, together with Lyapunov theory, it is proved that the states of closed-loop system converge to small regions around zero with fixed-time convergence rate. The simulation results confirm the benefits of developed scheme.

Gingipain from Porphyromonas gingivalis causes insulin resistance by degrading insulin receptors through direct proteolytic effects

Periodontitis is a critical risk factor for the occurrence and development of diabetes. Porphyromonas gingivalis may participate in insulin resistance (IR) caused by periodontal inflammation, but the functional role and specific mechanisms of P. gingivalis in IR remain unclear. In the present study, clinical samples were analysed to determine the statistical correlation between P. gingivalis and IR occurrence. Through culturing of hepatocytes, myocytes, and adipocytes, and feeding mice P. gingivalis orally, the functional correlation between P. gingivalis and IR occurrence was further studied both in vitro and in vivo. Clinical data suggested that the amount of P. gingivalis isolated was correlated with the Homeostatic Model Assessment for IR score. In vitro studies suggested that coculture with P. gingivalis decreased glucose uptake and insulin receptor (INSR) protein expression in hepatocytes, myocytes, and adipocytes. Mice fed P. gingivalis tended to undergo IR. P. gingivalis was detectable in the liver, skeletal muscle, and adipose tissue of experimental mice. The distribution sites of gingipain coincided with the downregulation of INSR. Gingipain proteolysed the functional insulin-binding region of INSR. Coculture with P. gingivalis significantly decreased the INSR–insulin binding ability. Knocking out gingipain from P. gingivalis alleviated the negative effects of P. gingivalis on IR in vivo. Taken together, these findings indicate that distantly migrated P. gingivalis may directly proteolytically degrade INSR through gingipain, thereby leading to IR. The results provide a new strategy for preventing diabetes by targeting periodontal pathogens and provide new ideas for exploring novel mechanisms by which periodontal inflammation affects the systemic metabolic state.