Dynamic Amplitude Research Articles

The Study on Deformation Characteristics and Stiffness Degradation of Loess near Active Faults

In order to explore the deformation characteristics and stiffness degradation of loess near active faults under subway loading, a series of dynamic triaxial tests were utilized to model the effect of subway loading on loess near active faults. The cumulative plastic strain characteristics and stiffness degradation laws of loess under different dynamic stress amplitudes and different loading frequencies are obtained, and the cumulative plastic strain and stiffness degradation indices are fitted using empirical formulas and degradation models, respectively. The results show that the growth rate of cumulative plastic strain and the attenuation degree of stiffness degradation index are large under large dynamic stress amplitude and low loading frequency. And the empirical formula accurately fits the cumulative plastic strain curve, and the correlation coefficient is more than 0.9. Furthermore, the degradation model fits the stiffness degradation index curve well, and the degradation parameter increases with increasing dynamic stress amplitude and decrease with increasing frequency. The findings of the study can be used to guide the construction and safe operation of subway tunnels that traverse active faults.

Parametric Analysis of Electrostatic Comb Drive for Resonant Sensors Operating under Atmospheric Pressure

The microelectrostatic comb resonator’s issues with high driving voltage and strong feed‐through coupling noise limit its practical use. In earlier studies, the design and structural optimization of microcomb resonators generally focused on lowering beam stiffness and raising electrostatic force density to enhance resonance displacement and lower driving voltage. However, for a microresonator that performs high‐speed resonance in the air, it is required to consider the three influencing elements of the electrostatic field, structural mechanics, and fluid mechanics to achieve the best dynamic resonance amplitude. In this paper, the parametric analysis of the comb‐driven resonator is carried out. First, the comb‐driven electrostatic force and all air‐damping terms are investigated using an electrostatic force analytical model considering edge effects, a damping analytical model simplified based on the thin‐film damping model, and the finite element model. The analysis results agree with the simulated results. To more accurately quantify the dynamic electrostatic force and damping coefficient, the electrostatic–structure–fluid three‐field indirect coupling model was used, and the law of the resonant amplitude of the resonator as a function of the structural parameters was obtained. The results show that, for the electrostatic comb resonator that oscillates at atmospheric pressure, to obtain a high‐voltage driving efficiency, a thin polysilicon film can be used to design narrow comb fingers that are dense in the vertical direction and loose in the lateral direction. To validate the accuracy of the model and the results of parameter analysis, an electrostatic comb‐drive resonator with shapes optimized from numerical simulations was fabricated. The results show that the driving efficiency is enhanced by 102%, with the chip area increased by 29%, which shows the superiority of parameter optimization.

Optimization Algorithm for Diffractive Optical Elements Based on Dynamic Amplitude Restriction

Optimization Algorithm for Diffractive Optical Elements Based on Dynamic Amplitude Restriction

Abnormal static and dynamic amplitude of low-frequency fluctuations in multiple brain regions of methamphetamine abstainers.

Methamphetamine (meth) addiction is a significant social and public health problem worldwide. The relapse rate of meth abstainers is significantly high, but the underlying physiological mechanisms are unclear. Therefore, in this study, we performed resting-state functional magnetic resonance imaging (rs-fMRI) analysis to detect differences in the spontaneous neural activity between the meth abstainers and the healthy controls, and identify the physiological mechanisms underlying the high relapse rate among the meth abstainers. The fluctuations and time variations in the blood oxygenation level-dependent (BOLD) signal of the local brain activity was analyzed from the pre-processed rs-fMRI data of 11 meth abstainers and 11 healthy controls and estimated the amplitude of low-frequency fluctuations (ALFF) and the dynamic ALFF (dALFF). In comparison with the healthy controls, meth abstainers showed higher ALFF in the anterior central gyrus, posterior central gyrus, trigonal-inferior frontal gyrus, middle temporal gyrus, dorsolateral superior frontal gyrus, and the insula, and reduced ALFF in the paracentral lobule and middle occipital gyrus. Furthermore, the meth abstainers showed significantly reduced dALFF in the supplementary motor area, orbital inferior frontal gyrus, middle frontal gyrus, medial superior frontal gyrus, middle occipital gyrus, insula, middle temporal gyrus, anterior central gyrus, and the cerebellum compared to the healthy controls ($ P < 0.05 $). These data showed abnormal spontaneous neural activity in several brain regions related to the cognitive, executive, and other social functions in the meth abstainers and potentially represent the underlying physiological mechanisms that are responsible for the high relapse rate. In conclusion, a combination of ALFF and dALFF analytical methods can be used to estimate abnormal spontaneous brain activity in the meth abstainers and make a more reasonable explanation for the high relapse rate of meth abstainers.

Dynamic Characteristics of Post-Cyclic Saturated Loess

Damage to soil structure caused by strong earthquakes is one of the main reasons for post-earthquake geohazard development. To investigate the nonlinear dynamic behaviors of the post-earthquake loess, a pre-shock reconsolidation test was designed to simulate the process of the loess undergoing earthquake and post-earthquake reconsolidation in a natural state. Furthermore, dynamic triaxial tests of the specimens before and after pre-shock action and consolidation stabilization with different over-consolidation ratios (OCR) were conducted to investigate the variety of the dynamic modulus and damping ratio of the saturated loess. The influence of pre-shock and reconsolidation on the dynamic behaviors was determined. Moreover, the mechanism of the changes after pre-shock and consolidation was discussed by combining the microstructure test results of soil samples before and after pre-shock and reconsolidation. The results suggest that the kinetic stiffness of the pre-shock saturated loess decreases significantly under the same consolidation conditions. The growth of the damping ratio-dynamic strain curve increases, and the deformation potential of the loess has a remarkable growth. With an increase in OCR, the dynamic elastic modulus after pre-shock increases continuously; however, the damping ratio decreases significantly. The dynamic stiffness increases and the deformation potential weakens significantly. The strong earthquake leads to the weakening of interparticle cementation, pore penetration, and structural reorganization in the local area, causes connecting of the macropores, and produces microfractures in the soil, which makes a significant decrease in the dynamic shear modulus ratio and an increase in the damping ratio of the loess, leading to the enhancement of soil dynamic nonlinearity and the attenuation of the dynamic strength. Moreover, the compaction effect of reconsolidation on the soil increases the interparticle friction and heals some microfractures, which leads to an increase in soil stiffness. This makes the maximum dynamic shear modulus and the maximum dynamic shear stress amplitude of the post-cyclic saturated loess perform at the same level compared with the natural loess without shock when the OCR equals three. However, the dynamic shear modulus and the damping ratio of the post-cyclic saturated loess are close to the natural loess when the OCR equals two.

Vibration Mitigation in the Railcar Floor Panel Using a Topologically Optimized Auxetic Layer

This paper aims at to improve the vibration behavior of the train floor panel by the use of a cellular auxetic layer. A field measurement is performed to obtain the vibrational frequency content of the body floor moving on the tangent track. Using acceleration sensors, the vibrational response is measured on the bogie (as the input excitation) and on the floor panel (as the observation response). Finite Element modeling for the floor panel is accomplished and measurement data are used for both the input excitation and the verification of the numerical results. The floor panel is a sandwich panel containing multiple layers. In this study, the conventional wooden layer of the panel is substituted with a cellular auxetic one with a re-entrant hexagonal pattern. Then, an optimization problem is defined while the topological parameters of the auxetic layer are the design variables and the dynamic performance of the panel is the objective function. The parameter of power–mass–ratio (PMR) is defined taking the effects of both weight and dynamic response amplitude into calculation. It is found that the PMR is reduced to almost 0.6 by replacing the wooden layer with an auxetic one, and after topological optimization, it is reduced to 0.35.

Load Distribution and Dynamic Response in Torque Split Applications

This study consists of constructing and analyzing gear mathematical models of torque split systems for contact pressure distribution and dynamic transmission error at different gear positions concerning phase angles. According to the method specified in the AGMA 927 standard, load distribution is calculated by considering shaft torsion and bending deformations. Partial contact loss may occur as a result of shaft bending with asymmetric gear positioning on a long shaft. The contact separation can be decreased by reaction force balancing if the driven gears are in the opposite position with respect to the drive gear. In the calculation of the dynamic transmission error of the torque split model, a parametric phase difference for the gear positions is proposed using gear geometry parameters. The variation of the dynamic response according to the change in the parametric phase angle in the torque split system is analyzed for the same values of each gear. Small changes in the phase values change the system response significantly. To obtain lower dynamic transmission error amplitude, the phase difference and gear positions are examined. The contact pressure distribution is validated by the finite element method, and the dynamic transmission error is compared with the experimental study in the literature.

Dynamic local metrics changes in patients with toothache: A resting-state functional magnetic resonance imaging study.

To study the dynamic changes of local metrics in patients with toothache (TA, Toothache) in the resting state, in order to further understand the changes of central neural mechanism in patients with dental pain and its effect on cognition and emotion. Thirty patients with TA and thirty matched healthy (HC) control volunteers were recruited, and resting-state functional magnetic resonance (rs-MRI) scans were performed on all subjects, and data were analyzed to compare group differences in three dynamic local indices: dynamic regional homogeneity (dReHO), dynamic low-frequency fluctuation amplitude (dALFF) and dynamic fractional low-frequency fluctuation amplitude (dfALFF). In addition, the association between dynamic local metrics in different brain regions of TA patients and scores on the Visual Analog Scale (VAS) and the Hospital Anxiety and Depression Scale (HADS) was investigated by Pearson correlation analysis. In this study, we found that The local metrics of TA patients changed with time Compared with the HC group, TA patients showed increased dReHo values in the left superior temporal gyrus, middle frontal gyrus, precentral gyrus, precuneus, angular gyrus, right superior frontal gyrus, middle temporal gyrus, postcentral gyrus and middle frontal gyrus, increased dALFF values in the right superior frontal gyrus, and increased dfALFF values in the right middle temporal gyrus, middle frontal gyrus and right superior occipital gyrus (p < 0.01, cluster level P < 0.05). Pearson correlation analysis showed that dReHo values of left precuneus and left angular gyrus were positively correlated with VAS scores in TA group. dReHo value of right posterior central gyrus was positively correlated with HADS score (P < 0.05). There are differences in the patterns of neural activity changes in resting-state brain areas of TA patients, and the brain areas that undergo abnormal changes are mainly pain processing brain areas, emotion processing brain areas and pain cognitive modulation brain areas, which help to reveal their underlying neuropathological mechanisms. In the hope of further understanding its effects on cognition and emotion.

Frequency- and temperature-dependent Payne effect and hysteresis loss of carbon black filled rubbers: Experimental study and model prediction

Many constitutive models have been proposed to model the Payne effect and to predict the hysteresis loss of the carbon black (CB)-filled rubber-like materials, but few works are related to clarifying which model is the more suitable one to model the Payne effect and to predict the energy dissipation. To this end, we present detailed comparisons of the classic quantitative models of the Payne effect proposed by Kraus, Huber-Vilgis and Maier-Göritz. The Payne effect is experimentally investigated under various frequency and temperature conditions, and the corresponding hysteresis loss loops are determined by DMA measurements. Classic quantitative models are used to describe the Payne effect and a viscoelastic model consisting of dynamic strain amplitude and loss modulus is used to calculate the energy dissipation, which can be used to verify the applicability of the classic quantitative models. The results show that the Maier-Göritz model is more suitable to describe the Payne effect, especially for the loss modulus. After comparison of the calculated energy dissipation with the experimental data, the Maier-Göritz model has the ability to predict the hysteresis loss.

Boundary control of vibration and dynamic tension fluctuation in a lifting system during the loading process

This article focuses on the boundary control for a lifting system during the loading process. A lifting system during the loading process is essentially a non-conservative system. The system dynamics are modelled based on the extended Hamilton’s principle. We consider the unmeasurable impact force caused by the uncertain materials falling velocity as a boundary disturbance and design a disturbance observer to eliminate its effect. The control system needs to guarantee the output constraints that the boundary vibration and dynamic tension fluctuation are both suppressed in a constrained scope of the desired value. Two appropriate boundary backstepping control schemes are proposed by actuators acting on different boundaries to realize the output constraints and to ensure the stability of the closed-loop system in theory. Numerical simulations are provided to illustrate the effectiveness of the proposed control laws in suppressing the cage vibration and rope dynamic tension fluctuation amplitude.

Dynamic changes in fractional amplitude of low-frequency fluctuations in patients with chronic insomnia.

Previous neuroimaging studies have mostly focused on changes in static functional connectivity in patients with chronic insomnia (CI) . Features of dynamic brain activity in patients with CI have rarely been described in detail. The present study investigated changes in dynamic intrinsic brain activity in patients with CI by dynamic fractional amplitude of low-frequency fluctuation (dfALFF) analysis. A total of 30 patients with CI and 27 healthy controls (HCs) were enrolled. We compared dfALFF between these two groups, and examined the correlation between changes in dfALFF and clinical symptoms of CI. Multivariate pattern analysis was performed to differentiate patients with CI from HCs. Compared with HC subjects, patients with CI showed significantly increased dfALFF in the left insula, right superior temporal gyrus, left parahippocampal gyrus, right amygdala, and bilateral posterior lobes of the cerebellum. Moreover, dfALFF values in the left insula and left parahippocampal gyrus showed a positive correlation with Pittsburgh Sleep Quality Index scores. A logistic regression model was constructed that had 96.7% sensitivity, 80.0% specificity, and 83.0% overall accuracy for distinguishing patients with CI from HCs. Dynamic local brain activity showed increased instability in patients with CI. The variability in dfALFF in the limbic system and brain areas related to sleep/wakefulness was associated with insomnia symptoms. These findings may provide insight into the neuropathologic basis of CI.

Model Test and Numerical Simulation Research of Reinforced Soil Retaining Walls under Cyclic Loads

The stress diffusion characteristics of reinforced soil retaining walls (RSW) with concrete-block panels under cyclic loads are studied. The distribution of the vertical dynamic earth pressure caused by an external load and the analysis of stress diffusion angles were studied using a model test and the numerical simulation model of the reinforced soil retaining wall was established to analyze the change in the stress diffusion angle. We then changed the parameters to investigate the influencing factors of the stress diffusion characteristics. The results showed that: the average value of the peak vertical dynamic earth pressure caused by an external load at the loading position of the RSW was a nonlinear distribution, decaying from top to bottom and increasing with the increase in the loading amplitude, while the change in the loading frequency number of loading cycles had no obvious rule. The results of model test and numerical simulation agree with each other. The diffusion angle of the stress caused by the external load of the reinforced body was basically between 50° and 65° in the range from 1.8 m to 1.2 m, the diffusion angle at the top was slightly larger than the middle, and the diffusion angle away from the wall was larger than the diffusion angle close to the wall. The main factors affecting the stress diffusion in reinforced soil retaining walls are the coefficient of reinforcement of the soil and the dynamic stress amplitude; the stress diffusion angle increased with an increase in the coefficient of the reinforcement of the soil and the dynamic stress amplitude. The conclusion of this paper can provide a reference for the design of reinforced soil structures.

Experimental Study on Dynamic Parameters of Calcareous Sand Subgrade under Long-Term Cyclic Loading

A long-term cyclic loading test of calcareous sand from an island reef in the South China Sea was conducted under conditions of unequal consolidation and drainage. The axial cumulative strain and dynamic characteristics of coral sand samples with different physical and mechanical properties were studied under different stress levels, yielding a model prediction formula. The results show that (1) the axial cumulative strain and dynamic elastic modulus increase with increasing vibration times of the cyclic load, whereas the dynamic damping ratio decreases with increasing cyclic vibration time; (2) the axial cumulative strain, elastic modulus, and damping ratio are affected by dynamic stress amplitude, load frequency, confining pressure, consolidation stress, compactness and moisture content; and (3) based on dynamic triaxial test results, the axial cumulative strain model of calcareous sand under cyclic loading and its permanent deformation prediction formula are established by introducing the cyclic stress ratio. Two parameters, the elastic modulus evolution parameter and the damping ratio evolution parameter, are introduced, and the axial cumulative strain is normalized. The results of this research have significance for understanding the long-term deformation and dynamic response of coral sand subgrade soil under cyclic vibration loads.

Vibration control of beams under moving loads using tuned mass inerter systems

Traditional tuned mass dampers (TMDs) have been proven efficient for the moving-load-induced vibration control of beams. However, a large tuned mass is required in TMDs to adjust the structural dynamic characteristics and achieve the demanded performance targets, which leads to additional dynamic effects and inconvenience of installation. The tuned mass inerter system (TMIS) is an ungrounded lightweight passive control device, which contains a suspended mass, a parallel-connected tuned spring and an inerter-based subsystem. In this study, the application and optimization of TMISs on vibration suppression of multi-span beam models under moving load series are investigated. Using the Bubnov-Galerkin integration method, the modal-superposition generalized system for specified modes of a beam with TMIS under successive moving load series is established. Then, a design strategy for TMISs is proposed to achieve the structural target performance demand by decreasing the moving load-induced resonant responses and attached tuned mass. In the optimization algorithm, the tuned mass ratio is taken as the optimal objective, and the limited dynamic response amplitude under different speed parameters is the constraint condition. A single-span simply supported beam with the TMIS under a moving load series is analyzed. The designed TMISs are tuned to the dominating mode with the maximum mass participate factor of the main structures. TMISs show good vibration mitigation compared to TMDs with equal tuned mass. Meanwhile, under the premise of identical structural performance demands, TMISs require less tuned mass than TMDs and achieve a lightweight control effect. The corresponding dynamic amplitude vs speed curves and time history response curves of beams with TMISs and TMDs are also depicted through comparative analyses. The vertical deflection and acceleration responses apparently decrease, and the resonance is mitigated due to the designed TMISs. The sensitivity analysis results indicate that TMISs attached to beams are insensitive to the perturbance of their parameters and the input moving load excitations; thus, TMIS proves to be a robust tuning system.

Effect of thermo-oxidative aging on the Payne effect and hysteresis loss of carbon-black filled rubber vulcanizates

In the tire industry, the Payne effect and hysteresis loss of carbon-black (CB) filled rubber vulcanizates are the most concerning issues. CB filled rubber vulcanizates are susceptible to thermo-oxidative aging in the applications. In this paper, the effects of thermo-oxidative aging are investigated from experimental and theoretical aspects. The specimens are subjected to thermo-oxidative aging at 80, 100 and 120 °C for various periods of time ranging from 1 to 6 days and then the dynamic mechanical tests are conducted. The results show that both the storage modulus and the loss modulus increase with increasing aging time. The hysteresis loss of the material shows an increasing tendency with the increase of dynamic strain amplitude, aging time and aging temperature. The Kraus model is used to describe the Payne effect and a viscoelastic model consisting of dynamic strain amplitude and loss modulus is used to calculate the energy dissipation.

Dynamic properties of polycrystalline ice subjected to cyclic triaxial loading

In order to study the dynamic behaviors of polycrystalline ice samples, cyclic triaxial loading tests were carried out on laboratory-grown polycrystalline ice (granular ice) samples under different temperatures (−2 °C, −6 °C, −15 °C), different confining pressures (0.5 MPa ~ 6 MPa), different frequencies, and different dynamic stress amplitudes. Laboratory results demonstrate that the hysteresis loops of dynamic stress-strain curves tend to change from sparse to dense and then to sparse again with the increasing number of cycles; the volume strain has a slight volume expansion at first, and then gradually changes to volume contraction. With the increase of the confining pressure, the volume contraction of the sample gradually increases and the hysteresis loops become narrow. The evolution law of the accumulated plastic strain under different conditions is similar, whose shape is roughly consistent with the three-stage creep test curve of quasi-static creep test. With the increasing number of cycles, the dynamic modulus increases rapidly first and then decreases slowly after reaching a certain number of cycles, whereas the dissipated energy density decreases rapidly first and then increases slowly after reaching a certain number of cycles. Under the same other conditions, the higher the stress state (or the lower the frequency), the higher the strain energy density, the faster the accumulated plastic strain develops, and the fewer cycles are needed to fail for the ice sample.

Accumulated plastic strain behavior of granite residual soil under traffic loading

In this study, the accumulated plastic strain (APS) of granite residual soil (GRS) under traffic loading is investigated via cyclic hollow-cylinder and triaxial tests. GRS is a special type of soil that is found widely in the hot and rainy areas of southern China. Because of insufficient understanding of the cumulative plastic deformation of GRS, how the dynamic stress amplitude, degree of saturation, effective consolidation stress, and stress path affect the APS under loading cycles is explored and analyzed. The results show that the effective consolidation stress inhibits the development of APS, whereas the dynamic stress amplitude promotes it. The APS of GRS increases with the degree of soil saturation, and its noticeable water-softening characteristics become the least favorable factor for soil deformation. The combined action of water softening and principal stress rotation helps to increase the APS significantly, and it leads to the emergence of an APS developmental curve that differs from the stable curve. Accounting for the water-softening characteristics of GRS and various stress conditions, a simple and easily adopted APS model is developed to predict the evolution of APS with loading cycles. Although specific to GRS in China, the findings of this study are expected to apply more widely to other weathered geomaterials.

Peculiarities of amplitude spectra of the third order for the early detection of indoor fires

The object of this study is the dynamics of hazardous parameters of the gas environment during the ignition of materials. The problem that was solved is the early detection of fires in the premises. The research results indicate the nonlinear nature of the dynamics of hazardous parameters of the gas environment in the absence and presence of materials ignition. It was established that the bispectrum amplitude, in contrast to the amplitude spectrum of the hazardous parameters of the gas medium, contains information on the reliable detection of fires. As such information, the value of the positive dynamic amplitude range of bispectrum is used. It was established that during the ignition of alcohol, the positive dynamics of the amplitude bispectrum of all dangerous parameters of the gas medium change. Significant changes are characteristic of smoke density (from 1 dB to 30 dB) and temperature (from 1 dB to 70 dB). The dynamic range of amplitude bispectrum for CO concentration is increased from 30 dB to 70 dB. Paper ignition was found to reduce the dynamic range of the amplitude bispectrum for smoke density from 40 dB to 20 dB. At the same time, the dynamic range of amplitude bispectrum for carbon monoxide concentration and temperature increases to 60 dB. The ignition of wood causes an increase in the dynamic range of the amplitude bispectrum relative to the concentration of carbon monoxide from 40 dB to 60 dB, and the temperature – from 30 dB to 40 dB. It was established that when textiles are ignited, the range of dynamics of the amplitude bispectrum for temperature increases from 10 dB to 60 dB. The results indicate that the dynamic characteristics of the amplitudes of the bispectrum of the gas medium can be used in practice for the early detection of fires in the premises

Adaptive Hodgkin–Huxley Neuron for Retina‐Inspired Perception

Biomimetic machine vision systems require structures, including an artificial retina to capture and process images, and an artificial network that imitates the cortex for visual inspection and identification tasks. One of the key challenges for biomimetic perceptional machine visual systems is the self‐adaptive behavior of the retina, which is known as the ability to adjust and eventually perceive objects through a wide range of environmental light intensities. To achieve this, current systems use either complex processing algorithms or specific devices with optoelectronic properties which results in complexity and less efficiency. Herein, an artificial retina circuit is reported to imitate the adaptation process to light (photopic and scotopic adaptation) of the perceptional biovisual system. The implementation of an artificial Hodgkin–Huxley neuron circuit based on adaptive VO2 memristors has helped the artificial retina to successfully demonstrate time‐varying activation and inhibition characteristics. The adaptable perception function under different illumination conditions is faithfully achieved by the artificial HH neuron based on the self‐adaptability of the memristor. The function is consistent with the dynamic light amplitude ranges of biological vision systems. More importantly, this development shows a pervasive way to design and fabricate a universal environmentally adaptable artificial system.

Abnormal cerebellar-prefrontal cortical pathways in obstructive sleep apnea with/without mild cognitive impairment.

Obstructive sleep apnea (OSA), a common respiratory sleep disorder, is often associated with mild cognitive impairment (MCI), which is a precursor stage to Alzheimer's disease (AD). However, the neuroimaging changes in patients with OSA with/without MCI are still under discussion. This study aimed to investigate the temporal variability of spontaneous brain activity in OSA. Fifty-two OSA patients (26 with OSA with MCI (OSA-MCI), 26 OSA without MCI (OSA-nMCI), and 26 healthy controls (HCs) underwent MRI scans and scale questionnaires. A dynamic amplitude of low-frequency fluctuation (dALFF) evaluation was performed to examine the time-varying nature of OSA-MCI and OSA-nMCI. Compared with OSA-MCI, OSA-nMCI had increased dALFF in the posterior cerebellar and right superior frontal gyrus; compared with HCs, OSA-nMCI patients showed increased dALFF in the right posterior cerebellum. A positive correlation between the bilateral posterior cerebellar lobes and right superior frontal gyrus was observed in OSA-MCI patients; however, in OSA-nMCI patients, a positive correlation was observed only between the bilateral posterior cerebellar lobes. The dALFF value of the left posterior cerebellar lobe was positively correlated with the apnea-hypopnea index (AHI), epworth sleepiness scale (ESS) score, and arousal index in OSA-nMCIs, while the dALFF value of the right posterior cerebellum was positively correlated with the AHI and negatively correlated with the lowest oxygen saturation (SaO2). This study argues that OSA-nMCIs and OSA-MCIs exhibit different temporal variabilities in dynamic brain functions, OSA-nMCIs may have variable intermediate states. We concluded that the functional abnormalities of the cerebellar-prefrontal cortex pathway in OSA-MCIs may cause cognitive impairment with OSA.