Body Movements Research Articles

Hydrodynamic analysis of an aquaculture tank-type floating breakwater integrated with perforated baffles

An innovative approach that integrates the floating breakwater (FB) with an offshore aquaculture tank is proposed to enhance economic benefits and hydrodynamic properties. To study the hydrodynamics of the integrated structure, a time-synchronized spatial-separated strategy is proposed and applied to the computational fluid dynamics (CFD) to facilitate the complex coupling between waves, mooring force, sloshing flow with the perforated baffle, and body motion. The mooring constraint was achieved by incorporating the catenary mooring theory, as well as employing the volume-averaged porous theory to simulate the perforated baffle effect to provide a low-energy environment required by aquaculture. Corresponding experimental tests were conducted to validate the reliability of the numerical model. The motion response, transmission and reflection coefficients, and sloshing behavior are analyzed to evaluate the hydrodynamics of the integrated structure. Besides, an index referred to as area-weighted-average velocity is introduced to further quantify the kinetic energy of sloshing flow. Results reveal the proposed aquaculture tank-type floating breakwater (AFB) can serve well as tuned liquid dampers (TLDs) to reduce the roll motion, and greatly improve the wave-attenuating capacity. Furthermore, the perforated baffles effectively weaken the sloshing energy at medium and finite filling depths, which are commonly operating depths for aquaculture in a floating closed containment system (FCCS). Overall, the floating breakwater integrated with the aquaculture tank is feasible due to a series of advantages.

Profiles of functioning of a group of children with cerebral palsy in Argentina: Preliminary data from the first national study.

Cerebral palsy (CP) affects body posture and movement coordination and is the most common cause of severe disability in the pediatric population. The diagnosis of CP is not a description of a person's functioning or interaction with their environment. Therefore, the diagnosis should be complemented with a description of functioning, using tools based on the biopsychosocial model proposed by the World Health Organization's International Classification of Functioning, Disability and Health (ICF). This report describes the preliminary data from a multicenter study conducted in Argentina with the aim of standardizing the description of the profiles of functioning of children and adolescents with CP. These data showed that the participants had some skills in sleep functions, mental functions of language, seeing functions, and in some environmental factors. They showed significant difficulties in categories such as maintaining body position, walking, and toileting.

Geometric Extended State Observer on [formula omitted] with Fast Finite-Time Stability: Theory and Validation on a Multi-rotor Vehicle

This article presents an extended state observer for a vehicle modeled as a rigid body in three-dimensional translational and rotational motions. The extended state observer is applicable to a multi-rotor aerial vehicle with a fixed plane of rotors, modeled as an under-actuated system on the state-space TSE(3), the tangent bundle of the six-dimensional Lie group SE(3). This state-space representation globally represents rigid body motions without singularities. The extended state observer is designed to estimate the resultant external disturbance force and disturbance torque acting on the vehicle. It guarantees stable convergence of disturbance estimation errors in finite time when the disturbances are constant, and finite time convergence to a bounded neighborhood of zero errors for time-varying disturbances. This extended state observer design is based on a Hölder-continuous fast finite time stable differentiator that is similar to the super-twisting algorithm, to obtain fast convergence. Numerical simulations are conducted to validate the proposed extended state observer. The proposed extended state observer is compared with other existing research to show its advantages. A set of experimental results implementing disturbance rejection control using feedback of disturbance estimates from this extended state observer is also presented.

Breathing the Earth: Bodily Exploration of Relationality in Eco-rituals and Dances

This video article is on the body movement, bodily exploration to make relationality with earth. On the body movements in environmental activism, rituals, and dances this article focuses. In spring 2003, the author attended a penance and walking called Samboilbae. Ever since, Samboilbae has been revered as representative, bodily, non-violent resistance in Korea. It has been recognized as highly sincere quest for resilience in human beings with more-than-human world, This video article tries to tell the participants’ bodily efforts and exploration toward embodiment of ecosomatic relationality between body and earth. At the second case, an invented ritual & performance based on old custom Maehyang, this article tries to tell ecological relationality embodied through the immersive or embedded matter and bodies in earth. At the last case, an invented ritual & performance based on old custom, Gaetje, the participants’ dances, ritual behaviors and materials were focused on. Bodily exploration into the forest and ocean for reciprocity, sensing and being sensed between human selves and earth, this article tries to tell.

Impact of Propofol Administered before Extubation on Respiratory Adverse Events in Pediatric Patients Undergoing Tonsillectomy and Adenoidectomy: A Randomized Controlled Trial

Aims/Background Perioperative respiratory adverse events (PRAEs) are common in pediatric anesthesia, especially in otolaryngology procedures. In this randomized controlled trial, we investigated the impact of administering propofol before extubation on PRAEs in pediatric patients undergoing tonsillectomy and adenoidectomy. Methods We enrolled children aged 3 to 8 years old, of American Society of Anesthesiologists (ASA) classes I to III, scheduled for tonsillectomy, and randomly divided them into propofol and control groups. The subjects in the propofol group received multiple small doses of propofol (0.5 mg/kg per dose, total 1–2 mg/kg) until the patient resumed regular spontaneous breathing and exhibited no bodily movements. The subjects in the control group received 0.15 mL/kg of saline. The primary outcome was the rate of PRAEs, such as laryngospasm, bronchospasm, breath-holding spell, severe coughing, desaturation, and airway obstruction, post-extubation. The secondary outcomes were the extubation time, pre-extubation Richmond Agitation-Sedation Scale (RASS) score, end-tidal sevoflurane concentration at extubation, incidence of postoperative agitation, time to consciousness, and Face, Legs, Activity, Cry, and Consolability (FLACC) pain score in the recovery room. Results were reported with risk ratios (RR) and their 95% confidence intervals (CI), as well as the p-values indicating statistical significance. Results A total of 239 patients were included, including 119 in the propofol group and 120 in the control group. Our findings indicated no significant difference in the rate of PRAEs between the two groups (5.9% vs 10.8%, RR: 0.54, 95% CI: 0.23 to 1.31, p = 0.17). However, the propofol group showed a notable decrease in moderate to severe coughs (13.4% vs 60.0%, RR: 0.22, 95% CI: 0.14 to 0.36, p < 0.001) and postoperative agitation (4.2% vs 60.8%, RR: 0.07, 95% CI: 0.03 to 0.17, p < 0.001). Conclusion This trial demonstrated that while administering repeated small doses of propofol before extubation does not significantly reduce respiratory adverse events in children undergoing tonsillectomy and adenoidectomy, it does significantly reduce the incidence of severe coughing, improving postoperative recovery and clinical outcomes. Moreover, propofol helps reduce postoperative agitation, enhancing the safety and effectiveness of postoperative care, and maintaining its valuable clinical role in postoperative management. Clinical Trial Registration ClinicalTrials.gov ( NCT05769842 ).

The biomechanics of public speaking: Enhancing political communication and persuasion through posture and gesture analysis

Effective public speaking is critical in political communication, where non-verbal cues such as posture, gestures, facial expressions, and body movements significantly influence audience perception. Despite the known impact of these biomechanics, research in diverse cultural contexts remains limited. This study addresses this gap by examining the biomechanics of public speaking in the Philippines, focusing on 16 political speakers and 211 audience participants from varied demographic backgrounds. The study uses advanced motion capture technology, high-definition video recordings, and audience perception surveys to investigate how specific non-verbal elements affect audience engagement and perception. Challenges include accurately measuring and isolating the effects of these biomechanical factors amidst varied cultural and linguistic influences. The findings reveal that an upright posture significantly enhances perceived confidence (r = 0.72, p = 0.003) and trustworthiness (r = 0.65, p = 0.004), while high-frequency gestures positively correlate with clarity (β = 0.47, p = 0.008) and persuasiveness (β = 0.66, p = 0.003). Head movements, such as nodding, significantly increase audience engagement (F-value = 5.73, p = 0.002), and high-intensity smiling enhances emotional responses (t-value = 4.86, p = 0.001). These results underscore the importance of biomechanics in political communication, demonstrating that specific gestures and postures are critical in conveying confidence and persuasiveness. The study contributes to the field by offering insights into the strategic use of body language, particularly in multicultural settings, to enhance audience engagement and speaker effectiveness.

Measuring Changes in Upper Body Movement Due to Fasting Using a Camera

Understanding activity levels during fasting is important for promoting healthy fasting practices. While most existing studies focus on step counts to objectively assess the impact of fasting on activity levels and behavioral changes, the results have been mixed. Despite evidence showing that individuals spend a significant amount of time sitting while fasting, there has been no objective measurement of body movement or activity levels during sitting and fasting. This research employs a video-based, unobtrusive human body movement measurement system to monitor upper body movements during fasting and non-fasting periods over several days. Key movement features, such as inactivity, movement speed, and movement scale, were automatically extracted from the video monitoring data using a computer vision pipeline. These features were then statistically compared using t tests between fasting and non-fasting periods, analyzed by hour of the day and across different days. The results of the monitoring of five participants during typical daily sitting office work and fasting for 3–5 days indicate no consistent pattern of upper body movement changes due to fasting among the participants.

A mobile electrical stimulator for therapeutic modulation of the vestibular system — design, safety, and functionality

Low-intensity noisy galvanic vestibular stimulation (nGVS) is a promising non-invasive treatment for enhancing vestibular perceptual performance and postural control in patients with chronic vestibular hypofunction. However, this approach has so far been studied mainly under laboratory conditions. Evidence indicates that continuous application of nGVS in daily life is necessary for it to be effective. To address this need, we have developed a mobile nGVS stimulator and conducted a series of pilot studies to evaluate its safety, tolerability, functionality, and therapeutic effects. The device is a lightweight, compact, and portable AC stimulator featuring a user-friendly interface for the individualized adjustment of nGVS parameters. It includes an integrated motion sensor that automatically activates stimulation during body movement and deactivates it during inactivity, optimizing its practical use in real-world settings. The stimulator adheres to strict safety standards and, in initial long-term use, has exhibited only mild side effects (e.g., skin irritation and headaches), likely attributable to the current electrode placement, which requires further optimization. As expected, the device consistently elicits known vestibular sensorimotor reflex responses in healthy individuals. Importantly, further pilot studies in healthy participants demonstrate that the device can reliably replicate known facilitating effects on vestibular perception and postural control. Together, these findings suggest that this mobile stimulation device can facilitate the translation of nGVS into therapeutic everyday use.

Biomechanical effects of different mandibular movements and torque compensations during mandibular advancement with clear aligners: a finite element analysis

IntroductionThis study aimed to evaluate the biomechanical effects of different mandibular movements and torque compensations during mandibular advancement with clear aligners using finite element analysis.MethodsModels were constructed to include the mandible, teeth, periodontal ligament (PDL), and clear aligners with buccal wings. Five oral muscles (superficial masseter, deep masseter, medial temporalis, posterior temporalis, and medial pterygoid) were represented as springs. Muscle values were measured and applied during different mandibular movements, including advancement distances (1–7 mm) and occlusal opening distances (2–4 mm). Different torque compensation angles (0°, 1°, 2°, and 3°) were applied to the mandibular central incisor.ResultsWhen the mandibular advancement was equal to or slightly excessed the occlusal opening distance, stress on the posterior PDL decreased and became more evenly distributed. Increasing the occlusal opening distance significantly raised stress on the posterior PDL and caused grater labial inclination of the mandibular anterior teeth. As the torque compensation increased, the labial inclination of the mandibular central incisor decreased, but stress on the PDL increased. Nearly complete bodily movement of the lower central incisor was achieved with torque compensation angles of approximately 15°, 19°, and 20° in models M1-2, M2-3, and M3-4, respectively.ConclusionTo maintain periodontal health during mandibular advancement, it is recommended that the mandibular advancement distance be equal to or slightly excessed the occlusal opening distance. Excessive occlusal opening distance increases stress on the posterior PDL and the labial inclination of mandibular anterior teeth, requiring careful control. Additionally, proper torque control of the mandibular interior teeth is crucial for optimal outcomes.

Increased survival of aquarium fish under acute hypoxia induced by prior intragastric administration of hydrogen peroxide

BACKGROUND: A solution of 3% hydrogen peroxide is an over-the-counter oxygen-releasing antiseptic, which forms oxygen foam when interacting locally with the wound surface. Therefore, this drug is widely used for mechanical cleansing of the surface of chronic wounds from purulent masses. The release of oxygen during catalase cleavage of hydrogen peroxide indicates the possibility of achieving anti-ischemic and anti-hypoxic action. AIM: A study of the effect of intragastric hydrogen peroxide on the resistance of aquarium fish to acute hypoxia. MATERIALS AND METHODS: Experiments were conducted on 80 adult aquarium fish of the guppy, blue neon, tri-linear parsings, swordtail fish and zebrafish (Danio rerio) breeds. To create acute hypoxia, each fish was placed in a transparent plastic container containing 5, 10 or 20 ml of fresh water at a temperature of +25 - +26 °C together with the fish, after which the container was hermetically sealed. Then, the motor activity of the fish's body, the respiratory movements of the gill arches, the opening of the oral cavity, the fluctuations of the fins and the dynamics of their coloration were monitored until the complete final immobilization of the fish and their death. Immediately before the experiment, 0.05 or 0.1 ml of fresh water in the control series and 0.05 ml or 0.1 ml of 0.05% hydrogen peroxide solution in the experimental series were injected into the stomach of the fish. The liquid was injected into the fish's stomach using a gastric mini-probe connected to an insulin syringe. RESULTS: It is shown that aquarium fish retain their viability in a small volume of fresh water inside a hermetically sealed container for a limited period of time, since fish continuously consume oxygen dissolved in water, thereby deepening hypoxia. At the same time, after sealing the container, the fish very quickly assume a stationary state, in which they remain for a certain period of time until their death. However, just before death, the immobility of the fish is disturbed. At the same time, the fish suddenly appear convulsive body movements, active movements of pectoral fins, mouths and gill arches, pectoral fins change their color, after which the fish defecate into the water. The results showed that the preliminary injection of 0.05 or 0.1 ml of 0.05% hydrogen peroxide solution into the stomach of fish prolongs the period of immobility of fish in hypoxia by an average of 20%. In all likelihood, the immobile state of fish is part of the complex of their adaptive adjustment to the cessation of oxygen supply to the water and reflects the availability of reserves of adaptation to hypoxia. The fact is that the absence of muscle contractions stops the muscles from using oxygen, which they use to generate energy. It is assumed that inside the stomach, hydrogen peroxide is absorbed into the blood, where, under the action of the enzyme catalase, it is split into water and gaseous oxygen, which replaces oxygen in the gills in the absence of oxygen in the surrounding water. CONCLUSIONS: Under model conditions, it was shown that pre-administration of 0.05 or 0.1 ml of 0.05% hydrogen peroxide solution into the stomach of fish increases their survival in conditions of acute hypoxia. Therefore, hydrogen peroxide can be considered as a potential antihypoxant for prolonging life in various types of suffocation, including the final stage of COVID-19.

X-ray fluoroscopy guided localization and steering of miniature robots using virtual reality enhancement

In developing medical interventions using untethered milli- and microrobots, ensuring safety and effectiveness relies on robust methods for real-time robot detection, tracking, and precise localization within the body. The inherent non-transparency of human tissues significantly challenges these efforts, as traditional imaging systems like fluoroscopy often lack crucial anatomical details, potentially compromising intervention safety and efficacy. To address this technological gap, in this study, we build a virtual reality environment housing an exact digital replica (digital twin) of the operational workspace and a robot avatar. We synchronize the virtual and real workspaces and continuously send the robot position data derived from the image stream into the digital twin with short average delay time around 20–25 ms. This allows the operator to steer the robot by tracking its avatar within the digital twin with near real-time temporal resolution. We demonstrate the feasibility of this approach with millirobots steered in confined phantoms. Our concept demonstration herein can pave the way for not only improved procedural safety by complementing fluoroscopic guidance with virtual reality enhancement, but also provides a platform for incorporating various additional real-time derivative data, e.g., instantaneous robot velocity, intraoperative physiological data obtained from the patient, e.g., blood flow rate, and pre-operative physical simulation models, e.g., periodic body motions, to further refine robot control capacity.

An Emotion Recognition Method for Humanoid Robot Body Movements Based on a PSO-BP-RMSProp Neural Network

This paper mainly explores the computational model that connects a robot’s emotional body movements with human emotion to propose an emotion recognition method for humanoid robot body movements. There is sparse research directly carried out from this perspective to recognize robot bodily expression. A robot’s body movements are designed by imitating human emotional body movements. Subjective questionnaires and statistical methods are used to analyze the characteristics of a user’s perceptions and select appropriate designs. An emotional body movement recognition model using a BP neural network (EBMR-BP model) is proposed, in which the selected robot’s body movements and corresponding emotions are used as inputs and outputs. The corresponding topological architecture, encoding rules, and training process are illustrated in detail. Then, the PSO method and the RMSProp algorithm are introduced to optimize the EBMR-BP method, and the PSO-BP-RMSProp model is developed. Through experiments and comparisons for emotion recognition of a robot’s body movements, the feasibility and effectiveness of the EBMR-BP model, with a recognition rate of 66.67%, and the PSO-BP-RMSProp model, with a recognition rate of 88.89%, are verified. This indicates that the proposed method can be used for emotion recognition of a robot’s body movements, and optimization can improve emotion recognition. The contributions are beneficial for emotional interaction design in HRI.

Numerical Simulation Study on Ice–Water–Ship Interaction Based on FEM-SPH Adaptive Coupling Algorithm

To address the impact of layered ice and seawater on polar vessels navigating in icy waters, this study employs a coupled finite element method (FEM) and smoothed particle hydrodynamics (SPH) algorithm to simulate the collision dynamics between the bow and stern of a designated icebreaker and the ice layers. The foundational principles and deployment strategies of the coupling algorithm have been meticulously delineated, with a subsequent simulation conducted to model the trajectory of icebreakers navigating through stratified ice conditions. The ice load on the hull, the movement of broken ice bodies, and the temporal variation of ice resistance during collision were analyzed. The method’s applicability and precision were substantiated through a comparative analysis between the simulated ice resistance outcomes and the ice load estimations derived from the Lindqvist formula. Finally, the differences between the bow and stern icebreaking methods were compared. The research findings indicate that the coupling algorithm demonstrates high precision in simulating the navigation of icebreakers under layered ice conditions, aligning with actual scenarios. This provides a solid foundation for further exploration of the ice load on polar vessels. Furthermore, at equivalent speeds and ice thicknesses, stern icebreaking was observed to induce greater oscillations in ice load and yield a higher mean resistance compared to bow icebreaking.

Cognitive effect of passively induced kinesthetic perception associated with virtual body augmentation modulates spinal reflex.

The virtual movement of an augmented body, perceived as part of oneself, forms the basis of kinesthetic perception induced by visual stimulation (KINVIS). KINVIS is a visually induced virtual kinesthetic perception that clinically suppresses spasticity. The present study hypothesized that central neural network activity during KINVIS affects subcortical neural circuits. The present study aimed to elucidate whether reciprocal and presynaptic inhibition occurs during KINVIS. Seventeen healthy participants were recruited (mean age: 27.9 ± 3.6 years), and their soleus Hoffmann-reflexes (H-reflexs) were recorded by peripheral nerve stimulation while perceiving the dorsiflexion kinesthetic illusion in the right-side foot (seated in a comfortable chair). Two control conditions were set to observe the same foot video without the kinesthetic illusion while focusing on the static foot image. Unconditioned H-reflex and two types of conditioned H-reflexes were measured: Ia (reciprocal inhibition) and D1 (presynaptic inhibition). Reciprocal Ia and D1 inhibition of the soleus muscle was significantly enhanced during the kinesthetic illusion compared to the condition without kinesthetic illusion (a post-hoc analysis using the Bonferroni test: Ia inhibition, p = 0.002; D1 inhibition, p = 0.049). This study indicates that kinesthetic illusion elicits an inhibitory effect on the monosynaptic reflex loop of Ia afferents, potentially inhibiting the hyperexcitability of the stretch reflex. These findings demonstrate that brain activity associated with visually induced kinesthetic illusions acts on spinal inhibition circuits. These insights may be valuable in clinical rehabilitation practice, specifically for the treatment of spasticity.

24-hour movement behaviors and changes in quality of life over time among community-dwelling older adults: a compositional data analysis.

Favorable movement behavior patterns, comprising more physical activity, less sedentary behavior, and sufficient sleep, may promote the maintenance of good quality of life (QoL) with advancing age. The aim of the present study was to investigate whether movement behaviors predict future changes in QoL among community-dwelling older adults over a four-year follow-up. Participants were 75-, 80- and 85-year-old community-dwelling older adults (n = 203) followed up for 4 years. Participants wore thigh- and trunk-mounted accelerometers for 3-7 days at baseline. Proportion of time-use in physical activity, standing and sedentary behavior were assessed based on body posture and movement intensity. Time in bed was determined using an automated algorithm. QoL was assessed during a home interview using the short Older People's Quality of Life Questionnaire at baseline and follow-up (range 13-65, higher scores indicate higher QoL). Compositional linear regression analysis was used to study whether baseline time-use composition predicts changes in QoL. Over the 4-year follow-up, QoL scores decreased by 5% on average. Higher physical activity in relation to the other movement behaviors was associated with increase in QoL over time (βilr 0.94, p = 0.013), but this association attenuated after adding baseline physical function into the model. Sedentary behavior, standing, and time in bed were not associated with changes in QoL. Theoretical reallocation of 30min of physical activity into sedentary behavior, standing or time in bed was estimated to decrease QoL by 0.5 (CI 95% -0.6 to -0.4), 0.6 (-0.7 to -0.5) and 0.4 (-0.5 to -0.3) points, respectively. Theoretical reallocation of physical activity into sedentary behavior, standing, and time in bed was found to be associated with prospective decline in QoL among older adults. Engaging more in physical activity and less in more passive activities may promote better QoL with advancing age.

Adsorbed microdroplets are mobile at the nanoscale

The extraordinary chemistry of microdroplets has reshaped how we as a community think about reactivity near multiphase boundaries. Even though interesting physico-chemical properties of microdroplets have been reported, "sessile" droplets' inherent mobility, which has been implicated as a driving force for curious chemistry, has not been well established. This paper seeks to answer the question: Can adsorbed microdroplets be mobile at the nanoscale? This is a tantalizing question, as almost no measurement technique has the spatiotemporal resolution to answer it. Here, we demonstrate a highly sensitive technique to detect nanometric motions of insulating bodies adsorbed to electrified microinterfaces. We place an organic droplet atop a microelectrode and track its dissolution by driving a heterogeneous reaction in the aqueous continuous phase. As the droplet's contact radius approaches the size of the microelectrode, the current versus time curve remarkably displays abrupt changes in current. We used finite element modeling to demonstrate these abrupt steps are due to nanometric movements of the three-phase boundary, where the nonaqueous droplet meets the aqueous phase and the electrode. Furthermore, the velocity with which the liquid interface moves can be estimated to tens-to-hundreds of nanometers per second. Our results indicate that processes that are driven by contact electrification and the frictional movement of bodies on a surface may be at play even when a droplet seems quiescent.

Numerical analysis of the effect of tunnel hydrofoil - stern flap on the motion stability of a double M-craft in regular waves

Abstract The double M-craft is a new type of high-performance multi-hull vessel that combines the gliding characteristics of a planing boat with the resistance-reducing characteristics of a hovercraft. But it also suffers from motion instability in regular waves. At present, there is scarce study on the effect of appendage on the motion stability of double M-craft in regular waves. By using the software STAR-CCM+ to numerically simulate the pitching and heaving motions of a double M-craft installed with tunnel hydrofoils and stern flaps in regular waves. Based on the overset mesh technology, the volume of fluid (VOF) method is used to capture the water-gas two-phase flow field. The 2-degree of freedom (2-DOF) motion of the rigid body is simulated by dynamic fluid body Interaction (DFBI). After investigating the effects of these combined appendages on the hydrodynamic performance, running attitude, and motion response of a double M-craft in regular waves, the optimal mounting parameters of the combined appendage have been obtained. The results have shown that all nine types of combined appendages can reduce the heave and pitch. The optimal combined appendage installation parameters include a hydrofoil longitudinal mounting position of 1/8L, angle of attack of 3°, stern flap length of 1.5%L, and flap angle of 5°, which can effectively reduce the pitching response by about 8% and reduce the swaying response by about 2.6%, and enhance its longitudinal motion stability.

Electron Transport and Ion Diffusion in Hydrogen-Bonded Interlayer Cross-Linked Graphene/MXene for Wearable Micro-Sensors.

2D graphene and MXene have attracted much attention in the field of energy storage devices and wearable sensors due to their excellent electrical conductivity and mechanical properties. However, the capacitance of their composites is limited by low electron transport and sluggish ion diffusion due to the lack of electron transport and ion diffusion channels between stacked interlayers. Herein, this work reports the possibility of using disodium terephthalate as an auxiliary conductive bridge to cross-link the interlayer interaction between graphene and MXene from theoretical analysis and experimental verification. The cross-linker with a dicarboxyl group and a conjugated structure forms hydrogen bonds with the hydroxyl groups on the surface of graphene and MXene to provide a pathway for interlayer electron transfer, while inhibiting interlayer stacking and ensuring an effective ion diffusion process. To verify the actual effect of this approach, micro-sensors are assembled by the integration of micro-supercapacitors. The assembled micro-sensors demonstrate real-time monitoring of body movements and temperature signals. This work provides a feasible strategy to promote electron transport and ion diffusion in layered composites to design next-generation multifunctional micro-devices.

Human Perception of the Emotional Expressions of Humanoid Robot Body Movements: Evidence from Survey and Eye-Tracking Measurements

The emotional expression of body movement, which is an aspect of emotional communication between humans, has not been considered enough in the field of human–robot interactions (HRIs). This paper explores human perceptions of the emotional expressions of humanoid robot body movements to study the emotional design of the bodily expressions of robots and the characteristics of the human perception of these emotional body movements. Six categories of emotional behaviors, including happiness, anger, sadness, surprise, fear, and disgust, were designed by imitating human emotional body movements, and they were implemented on a Yanshee robot. A total of 135 participants were recruited for questionnaires and eye-tracking measurements. Statistical methods, including K-means clustering, repeated analysis of variance (ANOVA), Friedman’s ANOVA, and Spearman’s correlation test, were used to analyze the data. According to the statistical results of emotional categories, intensities, and arousals perceived by humans, a guide to grading the designed robot’s bodily expressions of emotion is created. By combining this guide with certain objective analyses, such as fixation and trajectory of eye movements, the characteristics of human perception, including the perceived differences between happiness and negative emotions and the trends of eye movements for different emotional categories, are described. This study not only illustrates subjective and objective evidence that humans can perceive robot bodily expressions of emotions through only vision but also provides helpful guidance for designing appropriate emotional bodily expressions in HRIs.

Exploiting EEG to identify confused students in online learning: A machine learning model comparison

Abstract. The COVID-19 pandemic has forced most schools, including universities, to adopt online courses for teaching. Due to the breaking of the constraints of time and space, online courses still occupy a large proportion in education until now, and large-scale open online education courses will become a major trend in the future. Of course, problems also arise in this process. As teachers cannot receive feedback from students anytime and anywhere in online courses, such as micro expressions, body movements, etc., they cannot know whether students are confused. Therefore, how to effectively detect students' learning status has grown in popularity. In the last few years, machine learning has developed rapidly, and a large number of artificial intelligence have emerged, making it possible to detect whether students are confused by combining electroencephalography with machine learning. In order to determine whether students were confused, this study used a wireless single channel Mindset device to collect Electroencephalography (EEG) signals. Six machine learning modelsrandom forests, eXtreme Gradient boosting, K-nearest neighbors, gradient boosting machines, logistic regression, and support vector machineswere then chosen. The findings indicate that other machine learning models have a high accuracy rate in classifying students' bewilderment, with the exception of the logistic regression model. With a 99.69% accuracy rate, the eXtreme gradient boosting model performs better than a number of other models.