Symmetric Motion Research Articles

Optimization-based two-dimensional symmetric tossing motion prediction and validation.

Human motion has been analyzed for decades based on experimentally collected subject data, serving various purposes, from enhancing athletic performance to assisting patients' recovery in rehabilitation and many individuals can benefit significantly from study advancements. Human motion prediction, is a more challenging task because no experimental data are available in advance, particularly concerning repetitive tasks, such as box lifting and tossing, to prevent injury risks. Tossing, a common task in various industries, involves the simultaneous vertical and horizontal movement of objects but often results in bodily strain. This paper presents an optimization-based method for predicting two-dimensional (2D) symmetric tossing motion without relying on experimental data. The method employs sequential quadratic programming, which optimizes dynamic effort by incorporating both static and dynamic joint torque limits. To validate the proposed model, experimental data were collected from 10 subjects performing tossing tasks using a motion capture system and force plates. The predicted joint angles and ground reaction forces considering dynamic joint strength constraints were compared with their corresponding experimental data to validate the model. In addition, the predicted joint torques differences are compared between joint dynamics strengths and static strengths. The results showed that the predicted optimal tossing motions range between the maximum and minimum of the experimental standard deviation for kinematic data across all subjects and the ground reaction forces are also within the experimental data range. This supports the validity of the prediction model. The findings of this study could have practical applications, especially in preventing the potential risk of injuries among workers who have daily tossing jobs.

Case report of 2-year-old child with congenital torticollis and crossbite treated with functional orthopedics of the jaws

Satisfactory chewing is performed by an alternating bilateral pattern that depends on occlusal balance, the absence of occlusal interference or premature contacts, stability, good functioning of the temporomandibular joints (TMJs) and neuromuscular maturation. If mandibular functional imbalances occur, discrepancies in maxillomandibular development and future facial asymmetries may occur. The objective of this work was to remove dental interferences that cause anterior and posterior crossbite, as well as those that prevent the good execution of symmetrical lateroprotrusive movements (right side/left side), through occlusal adjustment and subsequent correction of maxillary asymmetry using the device; encapsulated. Clinical case report of a two-year-old female patient, with unilateral crossbite on the right side (anterior/posterior), diagnosed with congenital torticollis, difficulty breastfeeding and difficulty performing alternating lateral movements. with follow-up until the complete deciduous dentition. The treatment was divided into three stages. The first step was to correct the unilateral crossbite (anterior and posterior), on the right side, by making occlusal adjustment using a grid, and later with the addition of Planas Direct Tracks resin. The second stage used an encapsulated device to correct maxillary asymmetry. The third stage was completed after the eruption of the deciduous second molars with the functional analysis of lateral movements plus occlusal adjustments using a grid. Correction of unilateral crossbite (anterior and posterior) on the right side, symmetrization of the maxilla and better execution of lateroprotrusive movements. The results obtained in this case report suggest that the occlusal adjustment removed the dental interferences that caused the anterior/posterior crossbite on the right side; the maxilla was symmetrized with the distalization of sector 63-65, and the removal of dental interferences that prevented lateral movements made it possible to perform lateroprotrusive movements (right/left side) after the complete eruption of the primary teeth.

Eigenfunction expansion solution for the radiation problem of a uniform cylinder in front of a partially reflective wall

In this paper, the wave radiation problem of a vertical cylinder in front of a partially reflective vertical wall is solved by combining the eigenfunction expansion method and the mirror image method. To satisfy the partial reflection condition at the vertical wall, a scattering incident wave is introduced, which corresponds to the reduction scattering potential from the mirror image cylinder symmetrically distributed about the partially reflective wall and under symmetrical motion about the vertical wall with respect to the original cylinder. Subsequently, the scattering potentials generated by each of the two cylinders are derived using the eigenfunction expansion method on cylindrical coordinate systems with origins at the centers of the two cylinders. By applying Graf's addition theorem, the wave radiation problem is finally solved by transforming the incident scattering potential in the imaginary cylindrical coordinate system back to the original one of the cylinder itself and satisfying the body surface boundary condition. Using the numerical model developed in this paper, the effects of the parameters of the modulus and phase of the partial reflection coefficients as well as the distance between the partially reflective wall and the center of the cylinder on the added mass and radiation damping are investigated. The numerical results show that there are oscillations present in both the curves of added mass and radiation damping versus nondimensional wavenumber ka, the amplitude of the oscillations increases with the increase in the modulus of the reflection coefficient, and the peaks and troughs of the oscillations move to lower wavenumber ranges with increasing phase shift of the reflection coefficient. In addition, the distance between the cylinder and the vertical wall significantly affects the wavenumber range in which the peaks and troughs of the hydrodynamic coefficient curves appear, and the period of the oscillations decreases as the distance increases.

Competing Bifurcations Determine Symmetry Breaking During Droplet Snaps on Smooth Patterned Surfaces.

The shape and stability of a droplet in contact with a solid surface is affected by the chemical composition and topography of the solid, and crucially, by the droplet's size. During a variation in size, most often observed during evaporation, droplets on smooth patterned surfaces can undergo sudden shape and position changes. Such changes, called snaps, are prompted by the surface pattern and arise from fold and pitchfork bifurcations which respectively cause symmetric and asymmetric motions. Yet, which type of snap is likely to be observed is an open fundamental question that has relevance in the rational design of surfaces for managing droplets. Here we show that the likelihood of observing symmetric or asymmetric snaps depends on the distance between fold and pitchfork bifurcation points and on how this distance varies for droplets that grow or shrink in size on surfaces patterned with a smooth topography. Our results can help develop strategies to control droplets by exploiting smooth surface patterns but also have broader relevance in situations where different types of bifurcations compete in determining the stability of a system, for instance in snap-through instabilities observed in elastic media.

Movement Strategy Moderates the Effect of Spatially Congruent Cues on the Stability of Rhythmic Bimanual Finger Movements.

Spatially congruent cues increase the speed of bimanual reach decisions compared with abstract symbolic cues, particularly for asymmetric reaches. Asymmetric rhythmic bimanual movements are less stable than symmetric rhythmic movements, but it is not well understood if spatially congruent cues similarly increase the stability of asymmetric rhythmic bimanual movements. To address this question, in Experiment 1, participants performed symmetric and asymmetric bimanual rhythmic finger tapping movements at different movement frequencies in time with flickering spatially congruent and abstract symbolic stimuli. As expected, symmetric movements were more stable. Spatially congruent cues similarly increased the stability of symmetric and asymmetric movements compared with abstract symbolic cues. The benefits of spatial congruence and movement symmetry were restricted to high movement frequencies (>2 Hz). To better understand if the emergence of these effects at high movement frequencies was driven by a change in movement strategy, in Experiment 2, video of the hands was concurrently recorded during task performance. Markerless motion tracking software revealed that participants switched from discontinuous to continuous movement strategies with increasing movement frequency. Because discontinuous and continuous movements are thought to be controlled by distinct neurocognitive systems, this might explain why the beneficial effects of spatial congruence and response symmetry emerged only at high movement frequencies. Overall, results from the current study indicate that the perceptual quality of the stimulus use to cue movement frequency can have powerful effects on the stability of rhythmic bimanual movements, but that these effects may depend on whether discontinuous or continuous movement strategies are selected.

2015 개정 교육과정에 따른 <기본 수학> 교과서의 선분의 중점 지도에 관한 분석

Objectives The purpose of this study is to analyze whether to introduce coordinates that midpoint on the line seg-ment and the learning contents that show different description methods of the <Basic Mathematics> textbooks according to the 2015 revised curriculum. Methods To do this, seven <Basic Mathematics> textbooks according to the 2015 revised curriculum were analyzed. Results First, only three of seven <Basic Mathematics> textbooks introduce the coordinates of the midpoint of the line segment. Two of these were introduced in the coordinate plane, and the other one was provided to the auxil-iary space as a hint to solve the equation problem of the circle. Second, three of the seven <Basic Mathematics> textbooks presented a problem to be solved using the coordinates of the midpoint of the line segment. In the equation of the straight line, it is presented as a problem of finding a perpendicular bisector of a line segment, and in the equation of the circle, it was presented as a problem of finding an equation of a circle given both end points of the diameter. Third, the method of describing the contents of the symmetric movement about the straight line    was different depending on whether or not it was introduced into the coordinates of the center. Conclusions Changes in the curriculum due to the nature of the mathematics subject not only affect the teaching and learning methods of that part, but also the teaching methods of other parts. Therefore, it is necessary to con-tinuously study the learning contents and changes in teaching and learning materials such as textbooks according to changes in the curriculum.

Effect of integrated manual and verbal cueing on functional transfers in chronic stroke survivors: a randomized controlled study

Purpose The profession of physical therapy has historically relied on manual facilitation to improve motor control strategies and performance in persons rehabilitating from a stroke, yet there is insufficient evidence to support its use during functional task training. The purpose of this study was to determine the effects of integrated cueing (verbal and manual) and verbal cueing approaches during sit-to-stand training on midline alignment & muscle activation in chronic stroke survivors. Methods Twenty-one chronic right-brained stroke survivors with hemiplegia were randomly assigned to the Integrated Cueing or Verbal Only group and outcome measures were recorded using an 18-Camera Motion Capture System, force plates, and surface electromyography (EMG). Results Both groups demonstrated a significant improvement in symmetry toward the midline after thirty training repetitions. Significant improvements in muscle activation were found in two muscle groups on the affected side of the body in the Integrated Cueing group, gastrocnemius and rectus femoris. Conclusion Both the Verbal Only and Integrated Cueing groups made significant progress toward more symmetrical movement, yet more significant changes in the activation of hemiparetic extensor muscles were seen in the Integrated Cueing group. These findings support the use of manual cueing in movement activation and performance during the training of functional tasks. IMPLICATIONS FOR REHAB Physical therapists commonly use manual tactile cues to facilitate movement performance but there is currently insufficient evidence to support this use with stroke survivors. In a relatively small sample size, both verbal cues and integrated cues (verbal plus manual) improved symmetry during sit to stand in chronic right brain stroke survivors. Integrated cueing enhanced motor activation and performance during sit to stand better than verbal cues alone. Manual tactile cueing should be considered during functional task retraining.

Bilateral chronic cavitary pulmonary aspergillomas in an adult patient with recurrent tuberculosis: a case report and literature review

BackgroundAspergillomas are globular growths of Aspergillus fumigatus, a benign aspergillosis of the lungs. It usually affects patients who are immunocompromised and have anatomically defective lung structures. The majority of aspergilloma cases are asymptomatic, despite the fact that 10% of cases spontaneously resolve. Most patients do not have any symptoms from their lesions. Direct serological or microbiological evidence of an Aspergillus species along with radiologic evidence is required for the diagnosis of an aspergilloma.CaseWe describe a 35-year-old adult Oromo male patient who had been experiencing night sweats, an intermittent productive cough with sparse whitish sputum, loss of appetite, and easy fatigability for 3 months. At 5 years prior, he received treatment for pulmonary tuberculosis that was smear-positive and was subsequently certified healed. Objectively, he was tachypneic and had intercostal, subcostal, and supraclavicular retractions with symmetric chest movement. A high-resolution computed tomography scan revealed bilateral apical cavitary lesions with core soft tissue attenuating spherical masses and an air crescentic sign suggestive of aspergillomas, which were confirmed by sputum light microscopic examination. The patient was managed with antibiotics and antifungals.ConclusionAspergilloma is a symptom of chronic pulmonary aspergillosis, a category of lung disorders caused by a persistent Aspergillus infection. Primary aspergillomas are uncommon and frequently occur in people with compromised immune systems. A prolonged cough, fever, chest pain, and hemoptysis are all symptoms of pulmonary aspergillomas. The majority of the time, pulmonary aspergillosis is difficult to identify. Despite high mortality and morbidity rates, surgery is still the most effective treatment for pulmonary aspergilloma.

Design and Modeling of a Six-Bar Mechanism for Repetitive Tasks with Symmetrical End-Effector Motion

Design and Modeling of a Six-Bar Mechanism for Repetitive Tasks with Symmetrical End-Effector Motion

Concurrent perception of competing predictions: A "split-stimulus effect".

Visual illusions are systematic misperceptions that can help us glean the heuristics with which the brain constructs visual experience. In a recently discovered visual illusion (the "frame effect"), it has been shown that flashing a stimulus inside of a moving frame produces a large misperception of that stimulus's position. Across two experiments, we investigated a novel illusion (the "split stimulus effect") where the symmetrical motion of two overlaid frames produces two simultaneous positional misperceptions of a single stimulus. That is, one stimulus is presented but two are perceived. In both experiments, a single red dot was flashed when the moving frames reversed direction, and participants were asked to report how many dots they saw. Naïve participants sometimes reported seeing two dots when only one was presented, indicating spontaneous perception of the illusion. A Bayesian analysis of the population prevalence of this effect was conducted. The dependence of this effect on the frames' speed, the dot's opacity, spatial attention, as the presence/absence of pre-flash motion ("postdiction") was also investigated, and the features of this illusion were compared to similar motion position illusions within a predictive processing framework. In demonstrating this illusory "splitting" effect, this study is the first to show that it is possible to be simultaneously aware of two opposing perceptual predictions about a single object and provides evidence of the hyperpriors that limit and inform the structure of visual experience.

Diversity and transition of periodic motion of a periodically excited soft-impacting machinery

Dynamics of a periodically excited vibro-impact system with soft impacts is investigated. Essential features of period-one multi-impact motion group and correlated transition characteristics in low-frequency range are discussed in detail by the way of two-parameter bifurcation space providing qualitative domains for different periodic motions. The main focus is given to the effect of sensitive parameters including constraint stiffness k 0, clearance threshold b, and damping parameter ζ on the system response. The low-frequency characteristics in the finite-dimensional parameter space are particularly explored. It is found that the increase of k 0 induces multi-type bifurcation of period-one double-impact symmetrical motion, which induces a rich variety of periodic motions, and period-one multi-impact motion group orbit primarily exist in the small-clearance b and low-frequency ω zone. Based on the evolution irreversibility of adjacent period-one multi-impact orbit, the mechanism of singularies appearing in pairs and two different transition zones (hysteresis and liguliform zones) is studied, the result of which provides a theoretical reference value for the common low-frequency vibration instability phenomenon in the field of mechanical engineering. For small-damping coefficient ζ, period-one multi-impact motion has a large quantity, and the main bridge for the transition of adjacent period-one multi-impact motion is liguliform zone, which embraces period-one multi-impact asymmetrical motion and period-n multi-impact subharmonic motion and a certain chaotic zone. For large-damping coefficient ζ, the amount of period-one multi-impact motion group is reduced, and the main bridge for the transition of adjacent period-one multi-impact motion is hysteresis zone, where adjacent period-one multi-impact orbits can coexist according to initial conditions. As designing and renovating impact mechanical equipment, the reasonable matching law of dynamic parameters can be determined through two-parameter bifurcation space, which is conducive to making the system work in stable periodic motion and obtaining larger instantaneous impact velocity.

Mechanically compliant locking plates for diaphyseal fracture fixation: A biomechanical study.

Axial micromotion between bone fragments can stimulate callus formation and fracture healing. In this study, we propose a novel mechanically compliant locking plate which achieves up to 0.6 mm of interfragmentary motion as flexures machined into the plate elastically deflect under physiological load. We investigated the biomechanical performance of three compliant plate variations in comparison to rigid control plates with small and large working lengths in a comminuted bridge plating scenario using humeral diaphysis surrogates. Under static axial loading, average interfragmentary motion was 6 times larger at 100 N (0.38 vs. 0.05 mm) and nearly three times larger at 350 N (0.58 vs. 0.2 mm) for compliant plates than rigid plates, respectively. Compliant plates delivered between 2.5 and 3.4 times more symmetric interfragmentary motion than rigid plates (p < 0.01). The bi-phasic stiffness of compliant pates provided 74%-96% lower initial axial stiffness up to approximately 100 N (p < 0.01), after which compliant plate stiffness was similar to rigid plates with increased working length (p > 0.3). The strength to failure of compliant plates under dynamic loading was on average 48%-55% lower than rigid plate groups (p < 0.01); however, all plates survived cyclic fatigue loading of 100,000 cycles at 350 N. This work characterizes the improvement in interfragmentary motion and the reduction in strength to failure of compliant plates compared to control rigid plates. Compliant plates may offer potential in comminuted fracture healing due to their ability to deliver symmetric interfragmentary motion into the range known to stimulate callus formation while surviving moderate fatigue loading with no signs of failure.

Comparison of feed-forward control strategies for simplified vertical hopping model with intrinsic muscle properties

To analyse walking, running or hopping motions, models with high degrees of freedom are usually used. However simple reductionist models are advantageous within certain limits. In a simple manner, the hopping motion is generally modelled by a spring-mass system, resulting in piecewise smooth dynamics with marginally stable periodic solutions. For a more realistic behaviour, the spring is replaced by a variety of muscle models due to which asymptotically stable periodic motions may occur. The intrinsic properties of the muscle model, i.e. preflexes, are usually taken into account in three complexities-constant, linear and Hill-type. In this paper, we propose a semi-closed form feed-forward control which represents the muscle activation and results in symmetrical hopping motion. The research question is whether hopping motions with symmetric force-time history have advantages over asymmetric ones in two aspects. The first aspect is its applicability for describing human motion. The second aspect is related to robotics where the efficiency is expressed in term of performance measures. The symmetric systems are compared with each other and with those from the literature using performance measures such as hopping height, energetic efficiency, stability of the periodic orbit, and dynamical robustness estimated by the local integrity measure (LIM). The paper also demonstrates that the DynIn MatLab Toolbox that has been developed for the estimation of the LIM of equilibrium points is applicable for periodic orbits.

Symmetric Electron Transfer Coordinates are Intrinsic to Bridged Systems: An ab Initio Treatment of the Creutz-Taube Ion.

A long-standing question in electron transfer research concerns the number and identity of collective nuclear motions that drive electron transfer or localisation. It is well established that these nuclear motions are commonly gathered into a so-called electron transfer coordinate. In this theoretical study, we demonstrate that both anti-symmetric and symmetric vibrational motions are intrinsic to bridged systems, and that both are required to explain the characteristic shape of their intervalence charge transfer bands. Using the properties of a two-state Marcus-Hush model, we identify and quantify these two coordinates as linear combinations of normal modes from ab initio calculations. This quantification gives access to the potential coupling, reorganization energy and curvature of the potential energy surfaces involved in electron transfer, independent of any prior assumptions about the system of interest. We showcase these claims with the Creutz-Taube ion, a prototypical Class III mixed valence complex. We find that the symmetric dimension is responsible for the asymmetric band shape, and trace this back to the offset of the ground and excited state potentials in this dimension. The significance of the symmetric dimension originates from geometry dependent coupling, which in turn is a natural consequence of the well-established superexchange mechanism. The conceptual connection between the symmetric and anti-symmetric motions and the superexchange mechanism appears as a general result for bridged systems.

Symmetric Electron Transfer Coordinates are Intrinsic to Bridged Systems: An ab Initio Treatment of the Creutz–Taube Ion

AbstractA long‐standing question in electron transfer research concerns the number and identity of collective nuclear motions that drive electron transfer or localisation. It is well established that these nuclear motions are commonly gathered into a so‐called electron transfer coordinate. In this theoretical study, we demonstrate that both anti‐symmetric and symmetric vibrational motions are intrinsic to bridged systems, and that both are required to explain the characteristic shape of their intervalence charge transfer bands. Using the properties of a two‐state Marcus–Hush model, we identify and quantify these two coordinates as linear combinations of normal modes from ab initio calculations. This quantification gives access to the potential coupling, reorganization energy and curvature of the potential energy surfaces involved in electron transfer, independent of any prior assumptions about the system of interest. We showcase these claims with the Creutz–Taube ion, a prototypical Class III mixed valence complex. We find that the symmetric dimension is responsible for the asymmetric band shape, and trace this back to the offset of the ground and excited state potentials in this dimension. The significance of the symmetric dimension originates from geometry dependent coupling, which in turn is a natural consequence of the well‐established superexchange mechanism. The conceptual connection between the symmetric and anti‐symmetric motions and the superexchange mechanism appears as a general result for bridged systems.

Dynamic Interactions: Non-Integer-Order Heat-Mass Transfer in Magnetohydrodynamic Flow of Non-Newtonian Fluid over Inclined Plates

The heat and mass transfer phenomenon in the presence of a moving magnetic field has a wide range of applications, spanning from industrial processes to environmental engineering and energy conversion technologies. Understanding these interactions enables the optimization of various processes and the development of innovative technologies. This manuscript is about a non-integer-order heat-mass transfer model for Maxwell fluid over an inclined plate in a porous medium. The MHD flow of non-Newtonian fluid over the plate due to the natural convection of the symmetric temperature field and general motion of the inclined plate is investigated. A magnetic field is applied with a certain angle to the plate, and it can either be fixed in place or move along with the plate as it moves. Our model equations are linear in time, and Laplace transforms form a powerful tool for analyzing and solving linear DEs and systems, while the Stehfest algorithm enables the recovery of original time domain functions from their Laplace transform. Moreover, it offers a powerful framework for handling fractional differential equations and capturing the intricate dynamics of non-Newtonian fluids under the influence of magnetic fields over inclined plates in porous media. So, the Laplace transform method and Stehfest’s numerical inversion algorithm are employed as the analytical approaches in our study for the solution to the model. Several cases for the general motion of the plate and generalized boundary conditions are discussed. A thorough parametric analysis is performed using graphical analysis, and useful conclusions are recorded that help to optimize various processes and the developments of innovative technologies.

Ventricular Netrin-1 deficiency leads to defective pyramidal decussation and mirror movement in mice.

The corticospinal tract (CST) is the principal neural pathway responsible for conducting voluntary movement in the vertebrate nervous system. Netrin-1 is a well-known guidance molecule for midline crossing of commissural axons during embryonic development. Families with inherited Netrin-1 mutations display congenital mirror movements (CMM), which are associated with malformations of pyramidal decussation in most cases. Here, we investigated the role of Netrin-1 in CST formation by generating conditional knockout (CKO) mice using a Gfap-driven Cre line. A large proportion of CST axons spread laterally in the ventral medulla oblongata, failed to decussate and descended in the ipsilateral spinal white matter of Ntn1Gfap CKO mice. Netrin-1 mRNA was expressed in the ventral ventricular zone (VZ) and midline, while Netrin-1 protein was transported by radial glial cells to the ventral medulla, through which CST axons pass. The level of transported Netrin-1 protein was significantly reduced in Ntn1Gfap CKO mice. In addition, Ntn1Gfap CKO mice displayed increased symmetric movements. Our findings indicate that VZ-derived Netrin-1 deletion leads to an abnormal trajectory of the CST in the spinal cord due to the failure of CST midline crossing and provides novel evidence supporting the idea that the Netrin-1 signalling pathway is involved in the pathogenesis of CMM.

A randomized controlled trial investigating the impact of a single flash cupping session on patients with chronic lower back pain using multichannel surface electromyographic assessment.

Chronic lower back pain (CLBP) is one of the most common disorders worldwide. Flash cupping has the ability to relieve CLBP; nevertheless, its impact on CLBP and the likely mechanism of action have not been studied. The goal of this study was to assess the impact of a single, brief cupping session on CLBP and low back muscle activity using multichannel surface electromyography (sEMG). In this randomized controlled trial, 24patients with CLBP were enrolled and randomly assigned to the control group (treated by acupuncture) and cupping group (treated by acupuncture and flash cupping). Acupuncture was applied on the shen shu (BL23), dachang shu (BL25), and wei zhong (BL40) acupoints in both the groups. A brief cupping treatment was applied to the shen shu (BL23), qihai shu (BL24), dachang shu (BL25), guanyuan shu (BL26), and xiaochang shu (BL27) acupoints on both sides of the lower back in the cupping group. The numeric rating scale (NRS) was used to assess therapy efficacy for lower back pain (LBP) before and after treatment. Surface EMG data collected during symmetrical trunk flexion-extension movements were utilized to measure lower back muscle activity and the effectiveness of LBP therapy. There was no statistically significant difference (P= 0.63) in pain intensity between the two groups before and after treatment. There was a statistically significant difference (P= 0.04) between the control group and the cupping group in the sEMG topographic map parameter CoGx-To-Midline. This study established a connection between the action mechanism of flash cupping and enhanced horizontal synchronization of lower back muscular activity.

Deep Residual Network with a CBAM Mechanism for the Recognition of Symmetric and Asymmetric Human Activity Using Wearable Sensors

Wearable devices are paramount in health monitoring applications since they provide contextual information to identify and recognize human activities. Although sensor-based human activity recognition (HAR) has been thoroughly examined, prior studies have yet to definitively differentiate between symmetric and asymmetric motions. Determining these movement patterns might provide a more profound understanding of assessing physical activity. The main objective of this research is to investigate the use of wearable motion sensors and deep convolutional neural networks in the analysis of symmetric and asymmetric activities. This study provides a new approach for classifying symmetric and asymmetric motions using a deep residual network incorporating channel and spatial convolutional block attention modules (CBAMs). Two publicly accessible benchmark HAR datasets, which consist of inertial measurements obtained from wrist-worn sensors, are used to assess the model’s efficacy. The model we have presented is subjected to thorough examination and demonstrates exceptional accuracy on both datasets. The ablation experiment examination also demonstrates noteworthy contributions from the residual mappings and CBAMs. The significance of recognizing basic movement symmetries in increasing sensor-based activity identification utilizing wearable devices is shown by the enhanced accuracy and F1-score, especially in asymmetric activities. The technique under consideration can provide activity monitoring with enhanced accuracy and detail, offering prospective advantages in diverse domains like customized healthcare, fitness tracking, and rehabilitation progress evaluation.

QUANTIFICATION OF KINEMATIC AND MOTOR VARIABLES IN PARACANOEING THROUGH THE ACTION CAMERA: A STUDY EXPLORATORY

Paracanoeing is a speed boating sport, practiced by men and women, who seek to cover a distance of 200 meters in the shortest possible time. To generate the propulsion of the vessel and overcome the aerodynamic and hydrodynamic drags, the athletes perform the stroke motor gesture, which consists of bilateral cyclic and symmetrical movements with a two-blade paddle. Since, the motor performance in the modality can be influenced by motor aspects related to rowing and the athlete's ability to produce and maintain high speed indexes. Thus, the objective of the present study was to explore the different ways of quantifying variables through GPS and action camera technologies, as well as programs that systematize this information, being able to transform it into graphs through commonly used statistical programs. With this, it is possible to perform the interpretation and quantification of the variables through technological equipment, GPS and action camera, the data of a volunteer, a beginner athlete of paracanoeing, were analyzed, the speed, paddling index, paddling phases were analyzed ( water and air) and paddling frequency. In this way, the study opens the possibility to use the technique in paracanoeing training programs, with the objective of evaluating the athlete, since through the quantification of the variables it is possible to map the athlete's performance in each variable. Received: 2024/02/17 Reformulated: 2024/04/23 Accepted: 2024/04/23