Eye Blink Classification for Assisting Disability to Communicate Using Bagging and Boosting

Disability is a physical or mental impairment. People with disability have more barriers to do certain activity than those without disability. Moreover, several conditions make them having difficulty to communicate with other people. Currently, researchers have helped people with disabilities by developing brain-computer interface (BCI) technology, which uses artifact on electroencephalograph (EEG) as a communication tool using blinks. Research on eye blinks has only focused on the threshold and peak amplitude, while the difference in how many blinks can be detected using peak amplitude has not been the focus yet. This study used primary data taken using a Muse headband on 15 subjects. This data was used as a dataset classified using bagging (random forest) and boosting (XGBoost) methods with python; 80% of the data was allocated for learning and 20% was for testing. The classified data was divided into ten times of testing, which were then averaged. The number of eye blinks’ classification results showed that the accuracy value using random forest was 77.55%, and the accuracy result with the XGBoost method was 90.39%. The result suggests that the experimental model is successful and can be used as a reference for making applications that help people to communicate by differentiating the number of eye blinks. This research focused on developing the number of eye blinks. However, in this study, only three blinking were used so that further research could increase these number.

Identification of Fracturing Behavior In Thermally Cracked Granite Using The Frequency Characteristics of Acoustic Emission

The frequency characteristics of acoustic emission (AE) during triaxial compression of thermally cracked and unheated (“fresh”) granite samples were investigated with the aim of understanding the influence of pre-existing cracks on precursor information regarding macroscopic failure. The peak frequency during the damage process was the same for thermally cracked and fresh granites. Analysis of AE signals showed that signals with low peak frequency appeared before failure of the sample, implying the initiation of microfractures with progressive growth of cracks. The peak amplitude of the frequency spectrum recorded in the thermally cracked samples was much lower than that in the fresh samples. This result suggests two reasons for the difference in peak amplitude: reduction in shear modulus and the attenuation filtering phenomenon caused by thermal cracks. In particular, the maximum value of peak amplitude in the low-frequency band for the thermally cracked samples was smaller than that for fresh samples. This characteristic can be related to the stress drop and crack size. Assuming that pre-existing thermal cracks grow during the pre-failure stage, the events with low peak frequency and low peak amplitude in the heat-treated samples are interpreted as exhibiting a low stress drop because of the small rupturing area for individual events. Therefore, although AE signals with low frequency can be considered as precursors to rock failure, cracking behavior suggested by events with low frequency depends on the initial damage condition of the rock sample.

Choosing an approach to statistical processing of the ship’s pitching record

The developed instrumentation and software provides discrete values for the angles of a vessel’s list on an operational voyage in sea conditions at specified time intervals.The half-periods of pitching are considered; the half-period and the corresponding pitching amplitude can be obtained in three different ways: as the amplitude from one board to the other one with the reference of the initial peak-to-peak amplitude or with the reference of the final peak-to-peak amplitude; as the time interval of the ship listing on one side between zero roll angles. It was found that each method corresponds to its own, different from the others, amplitude-period statistics. This makes it difficult to compare different registrations and identify the essential reactions of the vessel to the seaway, unless a method is specified for determining the half-periods and linking the roll amplitudes to them. The proposal is justified to unify the processing by defining the half-period as the time of the ship listing on one board with the corresponding amplitude angle of the roll, that is, as the difference of the moments of time between two next values of the zero angle of the roll.

Modality differences in ERP components between somatosensory and auditory Go/No-go paradigms in prepubescent children

We investigated modality differences in the N2 and P3 components of event-related potentials (ERPs) between somatosensory and auditory Go/No-go paradigms in eighteen healthy prepubescent children (mean age: 125.9±4.2 months). We also evaluated the relationship between behavioral responses (reaction time, reaction time variability, and omission and commission error rates) and amplitudes and latencies of N2 and P3 during somatosensory and auditory Go/No-go paradigms. The peak latency of No-go-N2 was significantly shorter than that of Go-N2 during somatosensory paradigms, but not during auditory paradigms. The peak amplitude of P3 was significantly larger during somatosensory than auditory paradigms, and the peak latency of P3 was significantly shorter during somatosensory than auditory paradigms. Correlations between behavioral responses and the P3 component were not found during somatosensory paradigms. On the other hand, in auditory paradigms, correlations were detected between the reaction time and peak amplitude of No-go-P3, and between the reaction time variability and peak latency of No-go-P3. A correlation was noted between commission error and the peak latency of No-go-N2 during somatosensory paradigms. Compared with previous adult studies using both somatosensory and auditory Go/No-go paradigms, the relationships between behavioral responses and ERP components would be weak in prepubescent children. Our data provide findings to advance understanding of the neural development of motor execution and inhibition processing, that is dependent on or independent of the stimulus modality.

Activation-Inhibition dynamics of the oscillatory bursts of the human EEG during resting state. The macroscopic macroscopic temporal range of few seconds

The ubiquitous brain oscillations occur in bursts of oscillatory activity. The present report tries to define the statistical characteristics of electroencephalographical (EEG) bursts of oscillatory activity during resting state in humans to define (i) the statistical properties of amplitude and duration of oscillatory bursts, (ii) its possible correlation, (iii) its frequency content, and (iv) the presence or not of a fixed threshold to trigger an oscillatory burst. The open eyes EEG recordings of five subjects with no artifacts were selected from a sample of 40 subjects. The recordings were filtered in frequency ranges of 2 Hz wide from 1 to 99 Hz. The analytic Hilbert transform was computed to obtain the amplitude envelopes of oscillatory bursts. The criteria of thresholding and a minimum of three cycles to define an oscillatory burst were imposed. Amplitude and duration parameters were extracted and they showed durations between hundreds of milliseconds and a few seconds, and peak amplitudes showed a unimodal distribution. Both parameters were positively correlated and the oscillatory burst durations were explained by a linear model with the terms peak amplitude and peak amplitude of amplitude envelope time derivative. The frequency content of the amplitude envelope was contained in the 0–2 Hz range. The results suggest the presence of amplitude modulated continuous oscillations in the human EEG during the resting conditions in a broad frequency range, with durations in the range of few seconds and modulated positively by amplitude and negatively by the time derivative of the amplitude envelope suggesting activation-inhibition dynamics. This macroscopic oscillatory network behavior is less pronounced in the low-frequency range (1–3 Hz).

Empirical Correlations of Spectral Input Energy with Peak Amplitude, Cumulative, and Duration Intensity Measures

ABSTRACT In earthquake engineering, it is acknowledged that a vector of intensity measures (IMs) can better predict seismic structural responses than a single measure. Hence, a vector of IMs is widely applied in a number of applications, such as probabilistic seismic hazard analysis, probabilistic seismic risk analysis, and ground-motion selections. Spectral input energy (EI) has been demonstrated as a promising IM in earthquake engineering, especially in the energy-based seismic design of structures. However, this important measure has not been included in the vector of IMs. Therefore, it is worthwhile to incorporate EI with other important IMs by examining correlations. This study analyzes the empirical correlations of spectral EI with peak amplitude-based IMs, cumulative-based IMs, and duration-related IMs. It is found that spectral absolute EI has strong correlations with peak ground velocity at all investigated periods. However, spectral EI is negatively correlated with duration-based IMs. To demonstrate the applicability of the examined correlations, a simple example is finally presented by employing EI for the ground-motion selections and seismic hazard assessment based on the generalized conditional intensity measure approach.

A high-bandwidth low current transimpedance amplification circuit

A measuring circuit is designed based on the transimpedance amplifier. The methods of reducing parasitic capacitance and improving amplifier performance are introduced in detail. The influence of the parasitic capacitance generated by the feedback resistors on the bandwidth in the transimpedance amplification circuit is discussed. The circuit can measure the wide-dynamic-range low current ranging from 10-13 A to 10-5 A in four ranges. The circuit's bandwidth is up to 500 Hz when the circuit can normally work to measure a wide-range low current. The peak-to-peak amplitude of circuit noise is less than 0.22 pA. The current drift is less than 1.06 fA/∘C over a temperature range of 0∘C to 85∘C, and the integral nonlinearity is less than 0.25%.

Comparison of resting-state EEG between adults with Down syndrome and typically developing controls

Background Down syndrome (DS) is the most common genetic cause of intellectual disability (ID) worldwide. Understanding electrophysiological characteristics associated with DS provides potential mechanistic insights into ID, helping inform biomarkers and targets for intervention. Currently, electrophysiological characteristics associated with DS remain unclear due to methodological differences between studies and inadequate controls for cognitive decline as a potential cofounder. Methods Eyes-closed resting-state EEG measures (specifically delta, theta, alpha, and beta absolute and relative powers, and alpha peak amplitude, frequency and frequency variance) in occipital and frontal regions were compared between adults with DS (with no diagnosis of dementia or evidence of cognitive decline) and typically developing (TD) matched controls (n = 25 per group). Results We report an overall ‘slower’ EEG spectrum, characterised by higher delta and theta power, and lower alpha and beta power, for both regions in people with DS. Alpha activity in particular showed strong group differences, including lower power, lower peak amplitude and greater peak frequency variance in people with DS. Conclusions Such EEG ‘slowing’ has previously been associated with cognitive decline in both DS and TD populations. These findings indicate the potential existence of a universal EEG signature of cognitive impairment, regardless of origin (neurodevelopmental or neurodegenerative), warranting further exploration.

Transcranial Focused Ultrasound Neuromodulation of the Thalamic Visual Pathway in a Large Animal Model

Background: Neuromodulation of deep brain structures via transcranial ultrasound stimulation (TUS) is a promising, but still elusive approach to non-invasive treatment of brain disorders. Objective: The purpose of this study was to determine whether MR-guided TUS of the lateral geniculate nucleus (LGN) can modulate visual evoked potentials (VEPs) and cortical brain oscillations in a large animal model. Methods: The lateral geniculate nucleus (LGN) on one side was identified with T2-weighted MRI in sheep (all male, n=9). MR acoustic radiation force imaging (MR-ARFI) was used to confirm a tight sonication focus. Electroencephalographic (EEG) signals were recorded, and the visual evoked potential (VEP) peak-to-peak amplitude (N70 and P100) was calculated for each trial. Time-frequency spectral analysis was performed to elucidate the effect of TUS on cortical brain dynamics. Results: The VEP peak-to-peak amplitude was reversibly suppressed relative to baseline during TUS. Dynamic spectral analysis demonstrated a change in cortical oscillations when TUS is paired with visual sensory input, but not when TUS is applied by itself. Conclusion: TUS non-invasively delivered to LGN can neuromodulate visual activity and oscillatory dynamics in large mammalian brains.

EMG Analysis of Dominant and Non-Dominant Arm of Latissimus Dorsi Muscles in Bowlers of Karad, Maharashtra, India

BACKGROUND Latissimus dorsi plays an important role in bowlers. Different bowling techniques recruit latissimus dorsi at different phases of bowling. This causes the muscle to undergo excessive contraction than its limit. Despite widespread knowledge about the recruitment of latissimus dorsi in bowling, there is limited electromyographic (EMG) studies about latissimus dorsi. It is necessary to evaluate and document the recruitment of latissimus dorsi in dominant and non-dominant arm in bowlers, which is focused in this study. This study was done to analyse the surface EMG activity of latissimus dorsi muscle in dominant and non-dominant arm during bowling. METHODS A cross-sectional analytical study was carried out among 96 professional cricket bowlers from deluxe cricket club and Yashwanthrao Chavan’s cricket club in Karad. EMG electrodes were applied over the latissimus dorsi muscle and the bowlers were asked to perform the action of bowling. The root mean square (RMS) and mean peak amplitude of the dominant and non-dominant arm were recorded. RESULTS The RMS (12.45 ± 2.84) values and mean peak amplitude (131.77 ± 44.11) of the dominant latissimus dorsi varied significantly from non-dominant muscle (P = 0.0015). Wilcoxon test was utilized for analysis of within group parameters. CONCLUSIONS The result of the present study showed strong evidence to support high recruitment of dominant latissimus dorsi in professional bowlers suggests the changes occurred in the physiological as well as biomechanical muscular structure. KEY WORDS EMG, Dominant, Non-Dominant, Latissimus Dorsi, Fast Bowlers