Synchronization Analysis Research Articles

Quantized Control for Local Synchronization of Fractional-Order Neural Networks with Actuator Saturation

This brief discusses the use of quantized control with actuator saturation to achieve the local synchronization of master–slave fractional-order neural networks (FONNs). A refined sector condition (RSC) is proposed that addresses the issue of the simultaneous quantizer effects and actuator constraints. The RSC is used in the theoretical analysis of local synchronization in drive-response systems. The analysis employs inequality techniques on the Mittag–Leffler function and fractional-order Lyapunov theory. Additionally, this paper presents two convex optimization algorithms that aim to minimize the actuator’s costs and expand the admissible initial area (AIA). Finally, this paper employs a three-neuron FONN to demonstrate the efficacy of the proposed methods.

Event-triggered impulsive control for synchronization in finite time of fractional-order reaction–diffusion complex networks

This paper is concerned with the finite-time synchronization (FTS) issue for fractional-order reaction–diffusion complex networks (RDCNs). A finite-time stability principle, which plays a key role in the synchronization analysis later, is developed for fractional-order nonlinear impulsive system. A novel hybrid controller, which consists of a event-triggered controller and a impulsive controller, is designed to realize the global FTS objective for the considered network. By applying the Lyapunov stability theory and the fractional calculus, the global FTS conditions are addressed in the form of algebraic inequalities. In addition, the exclusion of Zeno behavior are proved for the designed event-triggered strategy. Finally, a numerical example is provided to illustrate the feasibility of the proposed control approach and the correctness of the theoretical results.

Performances of fissured red sandstone after thermal treatment with constant-amplitude and low-cycle impacts

In the engineering practices, it is increasingly common to encounter fractured rocks perturbed by temperatures and frequent dynamic loads. In this paper, the dynamic behaviors and fracture characteristics of red sandstone considering temperatures (25 °C, 200 °C, 400 °C, 600 °C, and 800 °C) and fissure angles (0°, 30°, 60°, and 90°) were evaluated under constant-amplitude and low-cycle (CALC) impacts actuated by a modified split Hopkinson pressure bar (SHPB) system. Subsequently, fracture morphology and second-order statistics within the grey-level co-occurrence matrix (GLCM) were examined using scanning electron microscopy (SEM). Meanwhile, the deep analysis and discussion of the mechanical response were conducted through the synchronous thermal analyzer (STA) test, numerical simulations, one-dimensional stress wave theory, and material structure. The multiple regression models between response variables and interactive effects of independent variables were established using the response surface method (RSM). The results demonstrate the fatigue strength and life diminish as temperatures rise and increase with increasing fissure angles, while the strain rate exhibits an inverse behavior. Furthermore, the peak stress intensification and strain rate softening observed during CALC impact exhibit greater prominence at increased fissure angles. The failure is dominated by tensile damage with concise evolution paths and intergranular cracks as well as the compressor-crushed zone which may affect the failure mode after 400 °C. The second-order statistics of GLCM in SEM images exhibit a considerable dependence on the temperatures. Also, thermal damage dominated by thermal properties controls the material structure and wave impedance and eventually affects the incident wave intensity. The tensile wave reflected from the fissure surface is the inherent mechanism responsible for the angle effect exhibited by the fatigue strength and life. Ultimately, the peak stress intensification and strain rate softening during impact are determined by both the material structure and compaction governed by thermal damage and tensile wave.

Tuberculous Lymphadenitis: Analysis of Cytomorphological Features with Utility of Genexpert MTB/RIF and Other Microbiological Test as an Adjunct to Cytology

Objectives: This study was undertaken to categorize various cytomorphological patterns of tuberculous lymphadenitis and with utility of Xpert MTB/RIF as an adjunct to cytology. Materials and methods: Cases based on various cytomorphological features were categorized into 3 patterns as 1. Granulomatous lymphadenitis (GL), 2. Necrotizing granulomatous lymphadenitis (NGL) 3. Necrotizing lymphadenitis (NL). The utility of microbiological test on cytosmears and histopathological examination were assessed in these categories wherever available. Results: Overall cytology had 86% sensitivity, 94% specificity, 92% positive and negative predictive value for diagnosis of tuberculosis. All these categories were correlated with microbiological test and gene Xpert wherever available. NGL had higher positive predictive value indicating that this group when subjected to microbiological methods provide definite diagnosis of tuberculosis. GL had higher specificity; hence negative microbiological test should be subjected to histopathological examination to rule out other causes of granulomatous lymphadenitis. GeneXpert when combined with cytologically suspicious smears, has high sensitivity of 85% and the agreement with culture is moderate as indicated by the kappa value of 0.4%. Conclusion: A synchronous analysis of cytomorphological features and GeneXpert and other microbiological test increases the diagnostic yield of Tuberculosis. Excisional biopsy for diagnosis of tuberculosis should be recommended only for patients in whom Fine Needle Aspiration Cytology PCR is negative or there is discrepancy with the clinical impression.

Retracted: Evaluation and Analysis of Animation Multimedia 3D Lip Synchronization considering the Comprehensive Weighted Algorithm

Retracted: Evaluation and Analysis of Animation Multimedia 3D Lip Synchronization considering the Comprehensive Weighted Algorithm

Oxidation Kinetics Analysis of Crude Oils with Different Viscosities

In order to compare the oxidation kinetics parameters of crude oils with different properties in the process of crude oil oxidation, six different crude oil samples were selected to analyze the oxidation characteristics of crude oils with different properties. In order to study the oxidation of crude oil, thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) synchronous analyzer were used for crude oil in the oxygen environment between 25 °C and 900 °C at a heating rate of 20 °C/min. The experimental results were based on crude oil oxidation using TGA and DTG experimental data to evaluate the oxidation mechanism of different crude oils, so as to better understand the situation in the oxidation reaction process. At the same time, the oxidation stage of crude oil was divided according to DSC data. Arrhenius method was used to analyze the oxidation kinetic parameters of crude oils with different properties, and the activation energies and pre-exponential factors of different crude oils were calculated. The experimental results show that the oxidation stage of crude oil can be divided into three stages: low-temperature oxidation, fuel deposition, and high-temperature oxidation. The low-temperature oxidation reaction begins at 280 °C, and the high-temperature oxidation reaction occurs at 400 °C. The low-temperature oxidation activation energy of an oil sample is 39.73–77.74 kJ/mol. The activation energy of the high-temperature oxidation is in the range of 106.27–264.47 kJ/mol. The activation energy of crude oil in the low-temperature oxidation stage increases with the increase of crude oil viscosity and decreases with the increase of crude oil viscosity in the high-temperature oxidation stage. Therefore, during the high-temperature oxidation stage, high-viscosity crude oil is more prone to reactions.

Analysis and control for synchronization of coupled reaction–diffusion neural networks with multiple couplings subject to topology attacks

This paper addresses the synchronization for coupled reaction–diffusion neural networks (CRNNs) with multistate couplings or multiple spatial-diffusion couplings suffering topology attacks. By selecting appropriate Lyapunov functional and utilizing the Kronecker product, several network synchronization criteria are formulated. Moreover, since networks suffering attacks may not be synchronized in some circumstances, two simple controllers are also developed. Finally, the effectiveness of the devised control schemes are verified through two numerical examples.

Experimental investigation of a fissured rock with thermal storage potential subjected to descending amplitude low cycle impacts

As the advancement of deep earth energy engineering in the 21st century, the challenges imposed by dynamic loads and high temperatures will be increasingly regular. This paper studied the dynamic mechanical behaviors and fracture characteristics of defective red sandstone (single fissure inclination of 0°, 30°, 60°, and 90°) subjected to thermal treatments (25 °C, 200 °C, 400 °C, 600 °C, and 800 °C) under descending amplitude low cycle (DALC) impact loading. The experiments were conducted using a modified split Hopkinson pressure bar (SHPB) system, and the fracture surfaces of the failed specimens were characterized through the use of high-resolution 3D laser scanning to obtain point cloud data. Subsequently, the fractal, roughness, texture, and elevation features of fracture surfaces were analyzed using the boxing-counting method, grayscale co-occurrence matrix (GLCM), and elevation-based statistics. The scanning electron microscopy (SEM) was utilized to study the fracture micromorphology as well. Additionally, the mechanisms of damage and fracture evolution were discussed based on the results of X-ray diffractometry (XRD), synchronous thermal analysis (STA), discrete element method (DEM), and strain energy density theory. The results demonstrate that the peak stress and dynamic elastic modulus deteriorate with rising temperatures and increase with larger fissure angles. While the peak strain, strain rate, and peak stress increase factor (PIF) exhibit the opposite trend. The threshold values for the intensification of these events are 400 °C and 60°. The damage is dominated by tensile cracks, which transition to shear at 30° and 60° due to temperature dependence. Meanwhile, the fractal dimension (DC), joint roughness coefficient (JRC), second-order statistics of GLCM, and elevation eigenvalues have been modeled using multiple regression analysis to investigate their interaction with temperature and fissure angle. The best-fit models illustrate significant linear or non-linear correlations between the aforementioned parameters and the mechanical parameters. Furthermore, the magnitude and distribution pattern of thermal cracks, as well as the growth of shear fractures, are governed by the dehydration, thermal expansion, phase transition, plasticization, thermal fracture, and thermal decomposition. Finally, strain energy density theory manifests promising prospects for understanding and predicting DALC impact fracture patterns of specimens.

Finite-Time Stochastic Synchronization of Multiweighted Directed Complex Networks via Intermittent Control

In this paper, finite-time synchronization (FTS) is addressed for directed multiweighted complex networks (MWCNs) with stochastic perturbations via intermittent control. Different from the previous FTS of single-weight networks, FTS of directed MWCNs is considered by introducing the allowable deviation synchronization bound. In synchronization analysis, a novel Lyapunov function is constructed by selecting a vector where the Chebyshev distance between this vector and their corresponding vectors for coupling matrices satisfies the allowable deviation synchronization bound. Furthermore, continuous control is not realistic due to limited resources. Accordingly, by discontinuous intermittent control, some suitable criteria can be derived to achieve FTS of directed MWCNs with stochastic perturbations. Finally, examples show the validity of the provided theoretical results.

Robustness Analysis of Exponential Synchronization in Complex Dynamic Networks with Time-Varying Delays and Random Disturbances

This paper aims to investigate the robustness of exponential synchronization in complex dynamic networks (CDNs) with time-varying delays and random disturbances. Via the Gronwall–Bellman lemma and partial inequality methods, by calculating the transcendental equations, the delays limits and maximum disturbance size of the CDNs are estimated. This means that the perturbed system achieves exponential synchronization if the disturbance strength is within our estimation range. The theoretical results are illustrated by several simulations.

Eigenvector-based analysis of cluster synchronization in general complex networks of coupled chaotic oscillators

Eigenvector-based analysis of cluster synchronization in general complex networks of coupled chaotic oscillators

The Effectiveness of a Multimodal Brain Empowerment Program in Mild Cognitive Impairment: A Single-Blind, Quasi-Randomized Experimental Study.

The present study aimed to determine a multimodal brain empowerment (MBE) program to mitigate the modifiable risk factors in mild cognitive impairment (MCI), and its therapeutic effects are unknown. MBE encompassing (1) tDCS, light therapy, computerized cognitive therapy (TLC) and (2) robot-assisted gait training, music therapy, and core exercise (REM) interventions were randomly assigned to 20 healthy young adults and 20 older adults with MCI. The electroencephalography (EEG) power spectrum and topographic event-related synchronization (ERS) analysis were used to assess intervention-related changes in neural activity during the MBE program. Outcome: The EEG results demonstrated that both multimodal TLC and REM decreased delta waves and increased theta, alpha, and beta waves (p < 0.001). ERS showed increased neural activation in the frontal, temporal, and parietal lobes during TLC and REM. Such enhanced neural activity in the region of interest supports potential clinical benefits in empowering cognitive function in both young adults and older adults with MCI.

Hydrothermal Synthesis of a Cellular NiO Film on Carbon Paper as a Promising Way to Obtain a Hierarchically Organized Electrode for a Flexible Supercapacitor.

The formation of a cellular hierarchically organized NiO film on a carbon paper substrate under hydrothermal conditions using triethanolamine as a base has been studied. The thermal behavior of the carbon paper substrate with the applied semi-product shell was studied using synchronous thermal analysis (TGA/DSC) and it was demonstrated that such modification of the material surface leads to a noticeable increase in its thermal stability. Using scanning electron microscopy (SEM), it was shown that the NiO film grown on the carbon fiber surface is characterized by a complex cellular morphology, organized by partially layered individual nanosheets of about 4-5 nm thickness and lateral dimensions up to 1-2 μm, some edges and folds of which are located vertically relative to the carbon fiber surface. The surface of the obtained material was also examined using atomic force microscopy (AFM), and the electronic work function of the oxide shell surface was evaluated using the Kelvin probe force microscopy (KPFM) method. The electrochemical parameters of the obtained flexible NiO/CP electrode were analyzed: the dependence of the specific capacitance on the current density was determined and the stability of the material during cycling was studied, which showed that the proposed approach is promising for manufacturing hierarchically organized electrodes for flexible supercapacitors.

Transient synchronous stability analysis and enhancement control strategy of a PLL-based VSC system during asymmetric grid faults

The stability of a voltage source converters (VSC) system based on phase-locked loop (PLL) is very important issue during asymmetric grid faults. This paper establishes a transient synchronous stability model of a dual-sequence PLL-based VSC system during low voltage ride-through by referring to the equivalent rotor swing equation of synchronous generators. Based on the model, the synchronization characteristics of the VSC system under asymmetric grid faults are described, and the interaction mechanisms, as well as the transient instability phenomena of positive and negative sequence PLL during asymmetric faults are explained. Using the equal area criterion, the influences of sequence control switching action, detection delay, and interaction between the positive and negative sequence PLL on the transient synchronous stability of the VSC system are analyzed, respectively. In addition, a transient stability assessment criterion based on the critical fault clearance angle and time and an enhancement control strategy based on the improved positive and negative sequence PLL are proposed. Finally, the analytical results are validated through simulation and experiments.

“Litchi-like” metastable Al/Ti/CuO micro-nano composites with enhanced combustion reaction and their energy characteristics

To design and prepare multifunctional metastable intermixed composites (MICs) with excellent properties, the enhanced “litchi-like” core-shell structure Al/Ti/CuO MICs were prepared by high-energy ball milling (Al/Ti/CuO-B). The morphology, structure, composition, thermal reactivity, energy release and combustion performance of the prepared MICs were investigated by scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and synchronous thermal analysis (DSC-TG), closed system constant volume combustion experiment, open system CO2 laser ignition experiment and high-energy laser-induced ablation experiment. This study reveals that, the obtained Al/Ti/CuO-B composites have a “litchi-like” core-shell structure, the components are evenly distributed and closely contacted. The exothermic reaction of Al/Ti/CuO-B should be divided into two stages. Due to the introduction of Ti and the special structure of litchi, Al/Ti/CuO-B has superior reactivity (Ea=178.15 kJ/mol), energy release (Q = 6443 J/g, Pmax =164.90KPa), shock wave propagation (v = 1028.33 m/s) and combustion performance than Al/Ti/CuO-P (simple physical mixing). The thrown Al/Ti/CuO composite particles will undergo secondary micro-reactions during the combustion, and a continuous multi-point “micro-explosion” phenomenon will occur, then self-sustainable combustion can be achieved through multi-level energy superposition release, which will enhance its reaction, combustion and energy release. Al/Ti/CuO-B undergoes an ultrafast reaction to generate plasma under high-energy laser induction, which expands and pushes the surrounding air to form a shock wave. The application of Al/Ti/CuO-B shows that the density, heat of detonation, shock wave overpressure, fireball diameter and temperature of composite structural explosive charge containing Al/Ti/CuO ring are all significantly improved.

Simple and Sensitive Method for Synchronous Quantification of Regulated and Unregulated Priority Disinfection Byproducts in Drinking Water.

Due to their elevated concentrations in drinking water, compared to other emerging environmental contaminants, disinfection byproducts (DBPs) have become a global concern. To address this, we have created a simple and sensitive method for simultaneously measuring 9 classes of DBPs. Haloacetic acids (HAAs) and iodo-acetic acids (IAAs) are determined using silylation derivatization, replacing diazomethane or acidic methanol derivatization with a more environmentally friendly and simpler treatment process that also offers greater sensitivity. Mono-/di-haloacetaldehydes (mono-/di-HALs) are directly analyzed without derivatization, along with trihalomethanes (THMs), iodo-THMs, haloketones, haloacetonitriles, haloacetamides, and halonitromethanes. Of the 50 DBPs studied, recoveries for most were 70-130%, LOQs for most were 0.01-0.05 μg/L, and relative standard deviations were <30%. We subsequently applied this method to 13 home tap water samples. Total concentrations of 9 classes of DBPs were 39.6-79.2 μg/L, in which unregulated priority DBPs contributed 42% of total DBP concentrations and 97% of total calculated cytotoxicity, highlighting the importance of monitoring their presence in drinking water. Br-DBPs were the dominant contributors to total DBPs (54%) and total calculated cytotoxicity (92%). Nitrogenous DBPs contributed 25% of total DBPs while inducing 57% of total calculated cytotoxicity. HALs were the most important toxicity drivers (40%), particularly four mono-/di-HALs, which induced 28% of total calculated cytotoxicity. This simple and sensitive method allows the synchronous analysis of 9 classes of regulated and unregulated priority DBPs and overcomes the weaknesses of some other methods especially for HAAs/IAAs and mono-/di-HALs, providing a useful tool for research on regulated and unregulated priority DBPs.

Synthesis and characterization of 1-phenylisatin incorporated chitosan/PEG nanoparticles: Interaction with bovine serum albumin and application in drug delivery

This study details the synthesis, characterization and protein binding efficiency of chitosan nanoparticles. Chitosan (CS) supported 1-phenylisatin (1-ph) loaded CS nanoparticles (NPs) (1-ph@CH-PEG/TPP) were synthesized utilizing the inotropic gelation method. The optimization of the composition of CSNPs was done using BBD. These formed CSNPs were then characterized with FTIR, SEM, TEM, TGA-DTA and XRD analyses. The addition of PEG increased the loading efficiency of CSNPs from 45.96 to 94.41% for bare nanoparticles to PEG encapsulated NPs, respectively. The drug encapsulated nanoparticles interacted with the universal protein BSA. The fluorescence quenching results showed that the system statically quenched its fluorescence. For BSA-1-ph and BSA-1-ph@CH-PEG/TPP systems, Ksv values decrease with increasing temperature (283–310 K; 6.15 × 104 L mol−1 to 1.19 × 104 L mol−1 for BSA-1-ph and from 2.52 × 104 L mol−1 to 1.09 × 104 L mol−1 for BSA-1-ph@CH-PEG/TPP). The binding calculations revealed that the 1-ph@CH-PEG/TPP system showed a decrease in its binding strength to the protein molecule as compared with the pure 1-ph system. This decrease in binding increases the therapeutic effect of the drug molecule and hence the produced CSNPs can be efficiently used as a potential drug delivery system. The UV, synchronous and 3D analysis confirmed the structural alteration of serum after binding. The effect of different metal ions on the binding profile of the 1-ph-BSA system was also investigated. Molecular docking results further validated the experimental finding.

Preparation, characterization, and thermal decomposition kinetics of high test peroxide gel

High test peroxide gel was prepared by low temperature freezing under the action of calcium ion compound with sodium alginate as a gelling agent. The High test peroxide gel was characterized by ultra depth of field microscope, Fourier infrared spectrometer, rheometer, synchronous thermal analyzer, and electron microscope scanner. The thermal decomposition behavior and reaction kinetics of the gel were investigated. The effective content of H2O2 in the gel before and after aging was also analyzed by KMnO4 titration. The results show that the content of sodium alginate and the concentration of calcium ion compound directly affect the gelling and rheological properties of high test peroxide gel, and the gel with low sodium alginate content had a more uniform tissue structure. The Eα and lg(A/s−1) of the high test peroxide gel decomposition reaction are 69.10 kJ mol−1 and 9.13, respectively. Na2O, CaO, CaCl2 and CaSO4 are the main components of the high test peroxide gel thermal decomposition condensate products. After ignition, a boron-based high test peroxide gel propellant can produce a steady combustion. After being stored at 263 K for 20 days, the effective content of H2O2 in the gel is 96.50%, and the decomposition rate is only 0.63%.

Heuristic Approach in Contemporary Chinese Digital Art: Following the Traditions of Buddhism

ABSTRACT This research aims to investigate how Artificial Intelligence-driven digital art, specifically Chatbot GPT-4, influences an individual’s comprehension of traditional Chinese Buddhism through the heuristic approach. The method of semi-structured interviews was established as a question framework that could be modified through synchronous analysis of the Chatbot GPT-4 responses. All the acquired information was processed using the record-keeping method and subsequently analysed employing the focus coding method. As a result of the analysis of the responses generated by the chatbot to structured interview questions, it was possible to determine that the optimal response for the system pertained to concise and precise queries that involved numerical information analysis (dates, formulas, chronology of events, etc.). In such instances, response time did not exceed 1.5 seconds. Notably, 90% of the questions received structured responses. In the case of essay writing, a series of three attempts were undertaken. In each case, the total content volume did not exceed 750 words: the first essay consisted of 450 words (45%), the second essay extended to 725 words (72.5%), and the third essay was composed of 710 words (71%).

Synchronization and stability analysis of an exponentially diverging solution in a mathematical model of asymmetrically interacting agents.

This study deals with an existing mathematical model of asymmetrically interacting agents. We analyze the following two previously unfocused features of the model: (i) synchronization of growth rates and (ii) initial value dependence of damped oscillation. By applying the techniques of variable transformation and timescale separation, we perform the stability analysis of a diverging solution. We find that (i) all growth rates synchronize to the same value that is as small as the smallest growth rate and (ii) oscillatory dynamics appear if the initial value of the slowest-growing agent is sufficiently small. Furthermore, our analytical method proposes a way to apply stability analysis to an exponentially diverging solution, which we believe is also a contribution of this study. Although the employed model is originally proposed as a model of infectious disease, we do not discuss its biological relevance but merely focus on the technical aspects.