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This work presents the excess noise and thermoelectric (Seebeck) measurements on polycrystalline vanadium dioxide (VO2) thin films. Noise spectral power density (SPD) of current fluctuations in the semiconducting (SC) phase had a typical flicker noise (f−γ) characteristic with an average slope parameter γ of 1.13. Normalized SPD (Sn) values obtained in the SC-phase indicate that the noise originates in the bulk of the film. On the contrary, in the metallic (M)-phase, γ values were greater than unity, and the observed Sn values indicated that the origin of the noise is most likely from the contacts or surface rather than the bulk. A general decrease was observed in Sn by a factor of 4–5 from the SC- to M-phase. Moreover, Sn in the SC-phase showed no temperature dependence. An interpretation based on the number of charge carrier fluctuations in Hooge's model led to an unrealistically high Hooge parameter and had to be ruled out. We propose that the fluctuations are related to the mobility fluctuations of carriers arising primarily from grain-boundary scattering which explains the observed characteristics well. The Seebeck coefficients (S) obtained under both heating and cooling schedules showed the n-type nature of magnetron-sputtered VO2 films in the SC-phase. Differently, in the M-phase, the S value was positive. The S values obtained from the cooling schedule signified the low percolation threshold of the metal-to-insulator transition already demonstrated for VO2 thin films grown on r-cut sapphire using the Efros–Shklovskii percolation model. [ABSTRACT FROM AUTHOR]

This study presents findings indicating that the ferroelectric tunnel junction (FTJ) or resistive random-access memory (RRAM) in one cell can be intentionally selected depending on the application. The HfAlO film annealed at 700 °C shows stable FTJ characteristics and can be converted into RRAM by forming a conductive filament inside the same cell, that is, the process of intentionally forming a conductive filament is the result of defect generation and redistribution, and applying compliance current prior to a hard breakdown event of the dielectric film enables subsequent RRAM operation. The converted RRAM demonstrated good memory performance. Through current–voltage fitting, it was confirmed that the two resistance states of the FTJ and RRAM had different transport mechanisms. In the RRAM, the 1/f noise power of the high-resistance state (HRS) was about ten times higher than that of the low-resistance state (LRS). This is because the noise components increase due to the additional current paths in the HRS. The 1/f noise power according to resistance states in the FTJ was exactly the opposite result from the case of the RRAM. This is because the noise component due to the Poole–Frenkel emission is added to the noise component due to the tunneling current in the LRS. In addition, we confirmed the potentiation and depression characteristics of the two devices and further evaluated the accuracy of pattern recognition through a simulation by considering a dataset from the Modified National Institute of Standards and Technology. [ABSTRACT FROM AUTHOR]

Suppression of 1/f noise in tunnel magnetoresistance (TMR) sensors is a central issue in the realization of magnetic field sensors with ultrafine magnetic field detectivity. Although AC modulation with an external magnetic field has been proposed as a method to shift the operating frequency of a sensor to a high frequency and substantially suppress 1/f noise, its effects on the two types of 1/f noise, that is, magnetic and electrical 1/f noise, are not well understood. In this study, we investigated the noise characteristics and signal detection performance of TMR sensors with an even-function resistance-magnetic field curve operated by the AC modulation method. For one TMR device in which the magnetic 1/f noise was dominant, AC modulation degraded the magnetic field detectivity owing to the additional noise induced by the AC modulation field. However, in another TMR device, in which the electrical 1/f noise was artificially enhanced by introducing lattice defects in the MgO tunnel barrier, AC modulation effectively suppressed the 1/f noise and improved the magnetic field detectivity by one order. This demonstrates that the AC modulation method using an external magnetic field is effective for magnetic field sensors in which electrical 1/f noise is dominant. [ABSTRACT FROM AUTHOR]

Previous work assessing the effect of additive noise on the postural control system has found a positive effect of additive white noise on postural dynamics. This study covers two separate experiments that were run sequentially to better understand how the structure of the additive noise signal affects postural dynamics, while also furthering our knowledge of how the intensity of auditory stimulation of noise may elicit this phenomenon. Across the two experiments, we introduced three auditory noise stimulations of varying structure (white, pink, and brown noise). Experiment 1 presented the stimuli at 35 dB while Experiment 2 was presented at 75 dB. Our findings demonstrate a decrease in variability of the postural control system regardless of the structure of the noise signal presented, but only for high intensity auditory stimulation.

We present the results of gas sensing using the fluctuation-enhanced sensing method in selected two-dimensional materials (2DMs). We claim that gas sensing selectivity can be improved further by considering semiconducting two-dimensional materials doped by noble metal nanoparticles. The 2DMs’ structures exhibit some imperfections defined by their structure, occurring repeatedly there. These imperfections are adsorption–desorption centers responsible for gas-sensing properties and generating flicker noise of various intensities. We consider how these imperfections can be modulated and utilized for fluctuations-enhanced gas sensing. We propose the decoration of 2DMs by noble metal nanoparticles that impact flicker noise. Additionally, we consider utilizing localized surface plasmonic resonance induced by irradiation at selected wavelengths. [ABSTRACT FROM AUTHOR]

Focusing on Rhenium disulfide (ReS2), a group VII transition metal di-chalcogenides (TMDC), being a promising contender system for future nanoelectronics and optoelectronics, here, we present an innovative pathway to experimentally achieve an almost barrier-free contact for the ReS2 field effect transistors (FETs) by using few layered graphene as contact electrodes, further supported by comparative first-principles analysis. Such barrier-free contacts enable the observation of metal-to-insulator transition with enhanced room temperature carrier mobility up to 25 cm2/Vs, linear Ids-Vds characteristic down to 80 K, along with the reduction of 1/f noise by more than two orders of magnitude. We further demonstrate a highly responsive gate- tunable phototransistor (R > 106 A/W) at an illumination wavelength of 633 nm. This work demonstrates a straightforward strategy to unlock the full potential of ReS2 for CMOS compatible future electronic and optoelectronic devices. [ABSTRACT FROM AUTHOR]

AlGaN/GaN high electron mobility transistors (HEMTs) with different GaN channel layers grown on AlN buffer layer are fabricated and investigated in order to optimize the device performances and to study the noise properties. To investigate the strain effect of the GaN channel layer grown on the AlN buffer layer, the positive shift of Raman peak is observed as the GaN channel becomes thinner. The threshold voltages (Vth) of the fabricated devices shift to positive direction according to the decreased GaN channel layer due to the decreased 2‐dimensional electron gas (2DEG) and deteriorated crystal quality of GaN channel layer. All devices demonstrated 1/f noise properties and the dominance of the carrier number fluctuations (CNF) noise mechanism. The largest trap density (Nt) value in the narrowest GaN channel device is because of the degraded crystal quality and the enhanced strain effect of the GaN channel layer. However, the lowest noise levels at the drain current (Id) > 10−6 A for the device with the GaN channel thickness of 30 nm grown on AlN buffer layer are observed to be due to the fully depleted GaN channel layer although its poor crystal quality. [ABSTRACT FROM AUTHOR]

Summary: Compared to the independent application of chopper stabilization or correlated double sampling (CDS), this paper proposed a 2nd‐order cascade of integrators with feedforward delta–sigma modulator (DSM) utilizing an innovatively synthetic technique of chopper‐integrator within CDS at 1st stage for reducing the flicker noise and DC offset cancelation from about 9.5 mV to −4.4 μV ± 115.6 μV (δ). On the regard of further enhancing the noise suppression and mitigating the nonlinearities of capacitor mismatch, instead of applying the dynamic elements randomization (DER) to the nonlinear correction of DAC under multi‐bits quantizer, here the operation of 3‐bits DER with scrambler has been intelligently employed on the 2nd integrators' sampling capacitors to gain the 2nd noise‐shaping characteristic in spite of 1‐bit quantizer. The noise floor could be theoretically scaled down by −16.1 dB at input frequency of 10 kHz within the limited bandwidth of 100 kHz. The prototype DSM was manufactured in 180‐nm BCD process with an active area of 0.2625 mm2 and achieves the SNDR‐based Schreier figure‐of‐merit (FoMS) of 144 dB and Walden figure‐of‐merit (FoMW) of 25.96 pJ/conv under a 3.3 V supply at 10 kHz working frequency. [ABSTRACT FROM AUTHOR]

With the development of globalization, learning a second language has received increasing attention from people. To improve English oral proficiency, a computer-aided online learning system for English oral pronunciation is studied. A denoising autoencoder is integrated into the system to create a simplified end-to-end recurrent neural network for pronunciation detection and diagnosis based on deep learning. The study first collected and preprocessed oral pronunciation data of English learners, including enhancing speech signals and reducing noise. Next, an RNN model with Long Short-Term Memory (LSTM) as the core was constructed to capture time series characteristics in pronunciation. And use DAE to extract features and reduce the influence of background noise to enhance the recognition of pronunciation features. At the same time, the study utilized web crawler technology to collect a large amount of oral pronunciation data from non-native English learners, and constructed an English oral corpus containing pronunciation errors. And in order to simulate real situations, white noise and pink noise were artificially added to the corpus in the study, and they were divided into training and testing sets in a ratio of 60% to 40%. The results showed that the classification accuracy of the system in the training and testing sets under white noise environment was 78.97% and 94.01%, respectively, and the classification accuracy in the pink noise environment was 76.19% and 94.03%, respectively. The system's error detection accuracy in vowel and consonant pronunciation detection is 88.91% and 91.68%, respectively, and the error correction accuracy in vowel and consonant pronunciation detection is 90.67% and 91.96%, respectively. In summary, the research on computer-aided online learning of English oral pronunciation based on Denoising Auto Encoders end-to-end recurrent neural networks has effectively improved learning efficiency. [ABSTRACT FROM AUTHOR]

Over the past decade, spin-glass simulations have improved to the point that they now access time- and length-scales comparable to experiments at the mesoscale. A recent series of thin-film field-cooled/zero-field-cooled magnetization (FC/ZFC) experiments demonstrated activated spin dynamics, with a temperature-independent activation energy proportional to the logarithm of the film thickness and with coefficients in remarkable agreement with the simulation. These measurements require the application of small magnetic fields, which has been shown to affect the spin-glass energy landscape. Measurements of the 1 / f noise in metallic spin-glasses have been previously shown to be a sensitive probe of the spin dynamics, and the measurements can be made without applying a magnetic field. In this mini-review, we review these techniques and discuss how transport measurements can fit into the current landscape of spin-glass measurements. We compare previous measurements to more recent measurements on similar films, made with ostensibly different cooling protocols, and compare both the previous and recent measurements to the magnetometry. The transport measurements—taken over a wider range of temperature than magnetometry—suggest that the maximum spin-glass energy barrier height is temperature-dependent, not fixed, possibly due to two-dimensional dynamics. We discuss this possibility, along with future measurements, which may be able to resolve this mystery. [ABSTRACT FROM AUTHOR]

ABSTRACT This paper presents a novel active inductor (AI) to improve the performance of a down‐conversion active mixer in terms of conversion gain (CG) and flicker noise. The proposed AI exhibits negative resistance and partially flat inductance over a wide frequency band of 0.5–4.5 GHz. The effect of inserting the AI between the source of the switching quad of a Gilbert cell mixer is theoretically analyzed. The proposed inductor‐less mixer, designed to operate at a 2.4‐GHz RF input frequency and a 10‐MHz IF output frequency, employs current reuse and self‐forward body bias (SFBB) techniques. The proposed circuit is simulated in Cadence Spectre‐RF using RF‐TSMC 0.18‐μm CMOS technology. Post‐layout simulations demonstrate that the proposed AI significantly reduces flicker noise by over 23 dB at an IF output frequency of 1 kHz and improves the CG by over 16 dB at an RF frequency of 2.4 GHz. The proposed mixer achieves a CG of 37.6 dB and a flicker noise corner frequency of 6 kHz. Additionally, it exhibits a third‐order intermodulation intercept point (IIP3) of −5.2 dBm and a double‐sideband noise figure (DSB‐NF) of 6.1 dB at the IF output frequency of 10 MHz. Operating with a 1.5‐V supply, the proposed mixer consumes 10.6 mW of power. [ABSTRACT FROM AUTHOR]

Echolocation is a vital method of spatial orientation for many visually impaired individuals who are willing to and able to learn it. Blind echolocators use a variety of sounds, such as mouth clicks, cane taps, or specialized sound-emitting devices, to perceive their surroundings. In our study, we examined the effectiveness of several different sounds used in echolocation by conducting trials with 12 blind and 14 sighted volunteers. None of the participants had received formal training in echolocation, though a number identified as self-taught experts. The sounds tested included those played from a loudspeaker, generated by a mechanical clicker, or made by the participants themselves. The task given to the participants was to identify the direction and distance to an obstacle measuring 1x2 meters in an outdoor environment, with the obstacle placed in one of nine possible positions. Our findings indicated that the blind participants displayed significantly better echolocation skills when compared to the sighted participants. The results of the blind participants were also strongly divided into two distinct subgroups—totally blind participants performed much better than those which were legally blind, but had some residual vision. In terms of sound comparisons, we found that sounds with a center frequency near 3-4kHz and a wide spectrum provided higher accuracy rates than those with lower frequency peaks. Sighted participants performed best with 3kHz and 4kHz percussion sounds, while the blind group performed best with blue and pink noise. The loudspeaker generated tones generally yielded better results than those generated by the participant (using a mechanical clicker, mouth clicks or hand claps). These results may be useful in developing training programs that teach echolocation as well as artificial sounds to improve echolocation effectiveness. [ABSTRACT FROM AUTHOR]

ABSTRACT This paper reports a low‐power, high dynamic range second‐order delta‐sigma modulator (DSM) for sensing applications. The DSM employs a hybrid CIFF‐B topology, consisting of a continuous‐time first stage and a discrete‐time second stage. The first stage is an OTA‐based RC integrator with inherent anti‐aliasing properties, while the second stage is a switched‐capacitor integrator. Offset and 1/f$$ 1/f $$ noise in the first stage are mitigated by the chopper‐stabilization technique, while those in the second stage are suppressed through the gain provided by the first stage. Furthermore, the OTA‐sharing technology is utilized in the second stage to realize signal addition before quantization, reducing design complexity. The hybrid DSM prototype is fabricated with a 180‐nm CMOS process and occupies an area of 0.123 mm2. Measurement results show peak SNDR/SNR/SFDR values of 95.8, 97.1, and 102.8 dB, respectively, with a current consumption of 10.7 μ$$ \upmu $$A from a 1.8‐V single supply. The reported DSM achieves a 103‐dB dynamic range in a 100‐Hz signal bandwidth, corresponding to a Schreier figure‐of‐merit (FoMs) value of 170.2 dB. [ABSTRACT FROM AUTHOR]

Rock-burst prediction is an important issue faced by deep coal mining operations and holds significant significance for ensuring the safety of workers and the sustainable development of mines. This study investigates the crack-propagation behavior of coal and magnetite under uniaxial compression, introduces the characteristic parameter γ within the framework of the flicker noise spectrum (FNS), analyzes the trends in the variation of acoustic emission (AE) b-value and γ-value, and explores the relationship between these two parameters. Experimental results reveal that the proportion of tensile cracks is significantly higher than shear cracks during the loading process, shear failure becomes the main factor as the specimen approaches failure. Both the b-value and γ-value are proven to effectively reflect the damage evolution process of coal and magnetite and exhibit noticeable changes prior to collapse. Specifically, the peak γ-value serves as a precursor indicator for coal and magnetite collapse. Furthermore, this study uncovers a negative linear relationship between the b-value and γ-value. By delving into the feature parameter γ of AE signals, this research offers a new perspective and approach for predicting the instability of coal and magnetite formations and monitoring dynamic hazards. It contributes to a better understanding of the damage evolution process of coal and magnetite formations and provides valuable guidance and reference for preventing and mitigating dynamic hazards associated with coal and magnetite. Highlights: A novel monitoring indicator for coal and magnetite dynamic hazards, known as the γ-value, was introduced within the framework of the Flicker Noise Spectroscopy method. The study revealed a notable negative linear correlation between the b-value and the γ-value derived from acoustic emission signals. Experimental and on-site data have demonstrated that b-value and γ-value can effectively prevent rock burst. [ABSTRACT FROM AUTHOR]

The well-known Rule07 is a simple thus efficient way to compare available technologies for IR imaging detectors in terms of dark current. The noise is then often estimated using a shot noise approximation on the dark current. Both II–VI and III–V communities use this rule of thumb as a reference for well-performing IR photodiodes. For HOT applications, a dark current close to this rule07 is considered a necessary condition but not a sufficient one to obtain a high-performance IR imager. Indeed, when limited by shot noise, rule07 describes well the noise behavior of the considered device. However, when considering low-frequency noise, it fails to describe the expected performances. In this paper, we focus on another figure-of-merit, dedicated to detector low-frequency noise rather than dark current. Systemic 1/f noise investigation in an IR detector was first reported by Tobin et al. in 1980. There is today a relative consensus on the fact that measured 1/f noise is proportional to the dark current. The ratio between the amplitude of the 1/f noise and the dark current of the same devices may therefore be used as a figure-of-merit for a given technology. This ratio (called the Tobin factor α T ) therefore appears adequate to compare different technologies as a figure-of-merit qualifying 1/f noise properties. This dimensionless ratio can also be very useful for optimizing a particular technology or process. However, in order to be relevant, this figure-of-merit must be estimated carefully as it appears, for instance, pixel pitch-dependent. Different examples of Tobin coefficient extraction are presented in this paper. We show that, depending on the technologies, the values of the Tobin coefficient can spread over several orders of magnitude. However, only low values result in high-quality IR imagers. Today, the best results we obtained show that α T = 10 - 5 is a state-of-art value to be compared with. [ABSTRACT FROM AUTHOR]

Today, one of the main challenges in the quantum infrared detection field is to increase the operating temperature in order to reduce size, weight and power-cost (SWAP). However, this leads to two major issues: an increase in the number of random telegraph signal (RTS) pixels and a residual fixed pattern noise (RFPN) instability. To identify these noise sources and assess the performance of a component, numerous measurements at the operating temperature are necessary, which can be laborious. Nevertheless, there exists a noise quality indicator for detectors at high temperatures known as the Tobin factor. In this paper, our objective is to investigate and understand the relationship between random telegraph signal (RTS) pixels and the Tobin factor. The aim of this study is to evaluate the relevance of the Tobin factor extracted at high temperatures to forecast noise performance at operating temperatures. [ABSTRACT FROM AUTHOR]

Context. HR 10 has only recently been identified as a binary system. Previously thought to be an A-type shell star, it appears that both components are fast-rotating A-type stars, each presenting a circumstellar envelope. Although showing complex photometric variability, spectroscopic observations of the metallic absorption lines reveal variation explained by the binarity, but not indicative of debris-disc inhomogeneities or sublimating exocomets. On the other hand, the properties of the two stars make them potential δ Scuti pulsators. Aims. The system has been observed in two sectors by the TESS satellite, and was the target of three observing visits by CHEOPS. Thanks to these new data, we aim to further characterise the stellar properties of the two components. In particular, we aim to decipher the extent to which the photometric variability can be attributed to a stellar origin. In complement, we searched in the lightcurves for transient-type events that could reveal debris discs or exocomets. Methods. We analysed the photometric variability of both the TESS and CHEOPS datasets in detail. We first performed a frequency analysis to identify and list all the periodic signals that may be related to stellar oscillations or surface variability. The signals identified as resulting from the stellar variability were then removed from the lightcurves in order to search for transient events in the residuals. Results. We report the detection of δ Scuti pulsations in both the TESS and CHEOPS data, but we cannot definitively identify which of the components is the pulsating star. In both datasets, we find flicker noise with the characteristics of a stellar granulation signal. However, it remains difficult to firmly attribute it to actual stellar granulation from convection, given the very thin surface convective zones predicted for both stars. Finally, we report probable detection of transient events in the CHEOPS data, without clear evidence of their origin. [ABSTRACT FROM AUTHOR]

Operational Modal Analysis (OMA) refers to the modal analysis with only output vibration signals of a structure in its operating state. Classic OMA has developed multiple recognition methods in both the time and frequency domains, where when the random excitation is unknown, the excitation chromaticity is usually treated as white color, which can often cause errors and affect the accuracy of identifying frequencies or damping ratios. In this article, the chromaticity recognition function is defined and a method Chromaticity Recognition Technology (CRT) for identifying noise chromaticity based on system response is proposed. Then, a simulation example is presented. The noise chromaticity is identified for the response of the system under four types of colored noise excitation, and the results of the identification of operational mode parameters with and without CRT are compared. Furthermore, the sensitivity of traditional OMA to different colored noise has been investigated. An experiment with a cantilever under base excitation of pink noise has been undertaken and the results demonstrate the feasibility of the proposed CRT in this paper. [ABSTRACT FROM AUTHOR]

Angular random walk (ARW), rate random walk (RRW), and bias instability (BI) are the main noise types in inertial measurement units (IMUs) and thus determine the navigation performance of IMUs. BI is the flicker noise, which determines the noise level of an inertial sensor. The traditional error modeling approach involves modeling the ARW and BI processes as RRW or Gauss–Markov (GM) processes, and this approach is applied as a suboptimal filter in the global navigation satellite system (GNSS)/inertial navigation system (INS) extended Kalman filter (EKF). In this paper, the random error identification processes for white noise and colored noise for inertial sensors are separated using the Allan variance and power spectral density methods and the equivalence of the stochastic process differential equations of bias instability and a combination of multiple first-order GM processes are derived. A colored noise compensation method is proposed based on the enhanced EKF model. Experimental results demonstrate that, compared to traditional error models, our proposed model reduces positional drift error in dynamic testing from 195 to 49 m, enhancing positional accuracy by 40.2%. These findings confirm the potential and superiority of our method in complex navigation environments. [ABSTRACT FROM AUTHOR]

Determining the presence and frequency of neural oscillations is essential to understanding dynamic brain function. Traditional methods that detect peaks over 1/f noise within the power spectrum fail to distinguish between the fundamental frequency and harmonics of often highly non-sinusoidal neural oscillations. To overcome this limitation, we define fundamental criteria that characterize neural oscillations and introduce the cyclic homogeneous oscillation (CHO) detection method. We implemented these criteria based on an autocorrelation approach to determine an oscillation's fundamental frequency. We evaluated CHO by verifying its performance on simulated non-sinusoidal oscillatory bursts and validated its ability to determine the fundamental frequency of neural oscillations in electrocorticographic (ECoG), electroencephalographic (EEG), and stereoelectroencephalographic (SEEG) signals recorded from 27 human subjects. Our results demonstrate that CHO outperforms conventional techniques in accurately detecting oscillations. In summary, CHO demonstrates high precision and specificity in detecting neural oscillations in time and frequency domains. The method's specificity enables the detailed study of non-sinusoidal characteristics of oscillations, such as the degree of asymmetry and waveform of an oscillation. Furthermore, CHO can be applied to identify how neural oscillations govern interactions throughout the brain and to determine oscillatory biomarkers that index abnormal brain function. [ABSTRACT FROM AUTHOR]

Quantum tunneling conductance of molecular junctions originates from the charge transport through the 𝜋-orbitals (𝜋-transport) and the 𝜎-orbitals (𝜎-transport) of the molecules, but the 𝜎-transport can not be observed due to the more rapid decay of the tunneling conductance in the 𝜎-system compared to that in the 𝜋-system. Here, we demonstrate that dominant 𝜎-transport can be observed in 𝜋-conjugated molecular junctions at the subnanometer scale using the scanning tunneling microscope break junction technique (STM-BJ). We have found that the conductance of meta -connected picolinic acid, which mainly occurs by 𝜎-transport, is ∼35 times higher than that of its para -isomer, which is entirely different from what is expected from 𝜋-transport through these systems. Flicker noise analysis reveals that the transport through the meta -connection exhibits more throughbond transport than the para -counterpart and density functional theory (DFT) shows that the 𝜎-system provides the dominant transport path. These results reveal that the 𝜎-electrons, rather than the 𝜋-electrons, can dominate charge transport through conjugated molecular junctions at the sub-nanometer scale, and this provides a new avenue toward the future miniaturization of molecular devices and materials. [ABSTRACT FROM AUTHOR]

Avalanche photodiodes (APDs) produce noise during operation, which affects the device performance. However, the previous research on its noise is mainly theoretical analysis and is only reflected as optical noise. Therefore, according to the characteristics of APD material and the mechanism of noise generation, the main noise of the device is analyzed in this paper. First, the test method of noise in APDs is established, including testing of dark noise, optical noise, and multiplication noise in high frequency bands. The main noises in APDs are 1/f noise, thermal noise, shot noise, generation recombination noise, and multiplication shot noise, and shot noise is suppressed by Fermi–Dirac distribution and Coulomb action. Second, the reliability of APDs is evaluated by measuring and analyzing the noise parameters of the device through thermal aging experiments. It is concluded that the defects introduced by thermal aging can be reflected by the change in noise, which is consistent with the results in the literature. This method can comprehensively obtain the noise in APDs, which is helpful to improve the working efficiency, life, and reliability of the device. [ABSTRACT FROM AUTHOR]

Room-temperature (RT) high-performance mid-wavelength infrared (MWIR) Lead Selenide (PbSe)/Cadmium Selenide (CdSe) heterostructure nanocrystal photoconductors are designed and fabricated on commercial silicon dioxide on silicon (SiO2/Si) wafer via vapor phase deposition. Tunable absorption edges at 3.75 and 4.0 μm are demonstrated with different sizes of the nanostructure. The devices are annealed in oxygen to make the thin film much more sensitive to MWIR light. The detectors are etched by the reactive ion etching method to define an active area of 17.5 × 20 μm2. All devices exhibit external quantum efficiencies exceeding 100%, a clear indication of photoconductive gain. 1/f noise is the dominating noise source, and it follows Hooge's empirical relation for a homogeneous semiconductor. RT peak specific detectivity (D*) of 2.17 × 1010 and 1.61 × 1010 Jones is achieved for pixels with absorption edge at 3.75 and 4 μm, respectively. [ABSTRACT FROM AUTHOR]

• Temporal correlations exist in the GRACE TWS time series, resulting in the presence of colored noise. • To show the impact of these correlations, we apply autoregressive noise model and variance component estimation model. • Neglecting these correlations leads to underestimation of trend uncertainty, misinterpreting its significance. Temporal correlations are prevalent in most geophysical time series data, leading to what is known as colored noise, which become more apparent in the frequency domain rather than time domain. Neglecting this type of noise in modeling can result in underestimated standard errors for the parameters of the model used to analyze the time series. As a result, statistical tests misinterpret the significance of these parameters, such as the overall trend rate, because the "signal to noise" ratio becomes incorrectly larger than it should be. In this study, we investigate the temporal correlations in the time series data from the Gravity Recovery and Climate Experiment (GRACE) mission. GRACE and its successor mission GRACE Follow-On (GRACE-FO) have been successfully employed to monitor global total water storage anomalies over two decades since its initial launch in 2002. We primarily utilize monthly GRACE mascon (mass concentration) solutions provided by NASA Goddard Space Flight Center (GSFC), examining both regional and global scales. The power spectrum density of the residuals, calculated after applying standard harmonic regression to each mascon time series on Earth's land, reveals an average spectral index of κ = −1. This indicates the predominance of flicker noise, one of the most common forms of colored noise in geodetic time series. Notably, the noise becomes more Brownian (κ < −1) in regions with intense hydrological events, while it tends to be more white noise (κ → 0) in areas with less water circulation compared to other land regions. This observation suggests that unmodelled hydrological events, such as droughts, floods, and ones associated with ice-melting, contribute to the residuals as colored noise in the time series. To account for this noise in our time series modeling, we primarily consider autoregressive (AR) moving average (MA) process, commonly known as ARMA, in addition to the standard variance component estimation for noise amplitudes. We focus on individual mascon blocks in the Türkiye Region and mascon solutions for 24 world's major river basins. Our findings demonstrate that an ARMA(1,1) model is sufficient for describing the noise in these regions. The results underscore the importance of considering colored noise, as it leads to approximately three times larger standard errors for the overall trend rate. This substantially impacts the significance of the trend rates. [ABSTRACT FROM AUTHOR]

Public interest in the potential benefits of white, pink, and brown noise for attention-deficit/hyperactivity disorder (ADHD) has recently mushroomed. White noise contains all frequencies of noise and sounds like static; pink or brown noise has more power in the lower frequencies and may sound, respectively, like rain or a waterfall. This meta-analysis evaluated effects on laboratory tasks in individuals with ADHD or elevated ADHD symptoms. Eligible studies reported on participants with diagnosis of ADHD or elevated symptoms of ADHD who were assessed in a randomized trial using laboratory tasks intended to measure aspects of attention or academic work involving attention or executive function while exposed to white, pink, and brown noise and compared with a low/no noise condition. Two authors independently reviewed and screened studies for eligibility. A random-effects meta-analysis was conducted with preplanned moderator analyses of age, diagnostic status, and task type. Publication bias was evaluated. The GRADE tool was used to assess certainty of the evidence. Sensitivity analyses were conducted to evaluate robustness. Studies of children and college-age young adults with ADHD or ADHD symptoms (k = 13, N = 335) yielded a small but statistically significant benefit of white and pink noise on task performance (g = 0.249, 95% CI [0.135, 0.363], p <.0001). No studies of brown noise were identified. Heterogeneity was minimal, and moderators were nonsignificant; results survived sensitivity tests, and no publication bias was identified. In non-ADHD comparison groups (k = 11, N = 335), white and pink noise had a negative effect (g = −0.212, 95% CI [−0.355, −0.069], p =.0036). White and pink noise provide a small benefit on laboratory attention tasks for individuals with ADHD or high ADHD symptoms, but not for non-ADHD individuals. This article addresses theoretical implications, cautions, risks, and limitations. Public interest in the potential benefits of white, pink, and brown noise exposure for enhancing task performance for individuals with attention-deficit/hyperactivity disorder (ADHD) has increased substantially. This systematic review and meta-analysis included 13 studies with 335 participants and found that white/pink noise improved cognitive performance for children and young adults with ADHD or significant ADHD symptoms. In contrast, white/pink noise impaired cognitive performance for individuals without ADHD. Positive effects of noise were small, but these results point to a possible low-cost, low-risk intervention that may benefit youth with ADHD. Additional studies are needed to confirm effects and identify safe and appropriate decibel levels. The potential detrimental effects for individuals without ADHD also requires further study. White Noise for ADHD: A Systematic Review And Meta-analysis; https://www.crd.york.ac.uk/prospero; CRD42023393992. [ABSTRACT FROM AUTHOR]

In biological neural networks, it has been well recognized that a healthy brain exhibits 1 / f noise patterns. However, in artificial neural networks that are increasingly matching or even out-performing human cognition, this phenomenon has yet to be established. In this work, we found that similar to that of their biological counterparts, 1 / f noise exists in artificial neural networks when trained on time series classification tasks. Additionally, we found that the activations of the neurons are the closest to 1 / f noise when the neurons are highly utilized. Conversely, if the network is too large and many neurons are underutilized, the neuron activations deviate from 1 / f noise patterns toward that of white noise. [ABSTRACT FROM AUTHOR]

The seemingly straightforward task of tying one's shoes requires a sophisticated interplay of joints, muscles, and neural pathways, posing a formidable challenge for researchers studying the intricacies of coordination. A widely accepted framework for measuring coordinated behavior is the Haken-Kelso-Bunz (HKB) model. However, a significant limitation of this model is its lack of accounting for the diverse variability structures inherent in the coordinated systems it frequently models. Variability is a pervasive phenomenon across various biological and physical systems, and it changes in healthy adults, older adults, and pathological populations. Here, we show, both empirically and with simulations, that manipulating the variability in coordinated movements significantly impacts the ability to change coordination patterns--a fundamental feature of the HKB model. Our results demonstrate that synchronized bimanual coordination, mirroring a state of healthy variability, instigates earlier transitions of coordinated movements compared to other variability conditions. This suggests a heightened adaptability when movements possess a healthy variability. We anticipate our study to show the necessity of adapting the HKB model to encompass variability, particularly in predictive applications such as neuroimaging, cognition, skill development, biomechanics, and beyond. [ABSTRACT FROM AUTHOR]

The pursuit of sub‐1‐nm field‐effect transistor (FET) channels within 3D semiconducting crystals faces challenges due to diminished gate electrostatics and increased charge carrier scattering. 2D semiconductors, exemplified by transition metal dichalcogenides, provide a promising alternative. However, the non‐idealities, such as excess low‐frequency noise (LFN) in 2D FETs, present substantial hurdles to their realization and commercialization. In this study, ideal LFN characteristics in monolayer MoS2 FETs are attained by engineering the metal‐2D semiconductor contact and the subgap density of states (DOS). By probing non‐ideal contact resistance effects using CuS and Au electrodes, it is uncovered that excess contact noise in the high drain current (ID) region can be substantially reduced by forming a van der Waals junction with CuS electrodes. Furthermore, thermal annealing effectively mitigates sulfur vacancy‐induced subgap density of states (DOS), diminishing excess noise in the low ID region. Through meticulous optimization of metal‐2D semiconductor contacts and subgap DOS, alignment of 1/f noise with the pure carrier number fluctuation model is achieved, ultimately achieving the sought‐after ideal LFN behavior in monolayer MoS2 FETs. This study underscores the necessity of refining excess noise, heralding improved performance and reliability of 2D electronic devices. [ABSTRACT FROM AUTHOR]

This article proposed a technique for a low‐power and fast start‐up voltage‐controlled oscillator (VCO) for a high data rate 5 G New Radio (5G‐NR) application. The 5G‐NR high data rate signals require a fast start‐up VCO to accommodate the short pulse width. In this proposed work, a cross‐coupled pair (XCP) is integrated with a center‐tapped orthogonal symmetry inductor placed at the gates of the XCP, forming an inductive booster VCO (IBVCO). The inductive impedance at the gate of the XCP preserve the symmetry signal profile of the output voltage swing while alleviating the intrinsic parasitic capacitance effect and flicker noise effect of the transistor under the absence of the tail current source. The concept proves with the improvement on the phase noise performance and generating a fast start‐up without affecting the VCO bandwidth. The VCO also provides the enhancement of the output voltage swing under low power consumption. The IBVCO has been fabricated in 180 nm complementary metal oxide semiconductor technology and consumes a minimum area of only 0.7 mm2. The IBVCO achieved a 13% tuning range from 3.3 to 3.75 GHz bandwidth with a supply voltage, VDD of 0.7 V. The total power consumption is 1 mW with a corresponding phase noise of −122.60 dBc/Hz and a Figure of Merit (FoM) of 193.48 dBc/Hz at 3.52 GHz carrier center frequency at 1 MHz offset. The start‐up time of the VCO achieved is 5 ns. [ABSTRACT FROM AUTHOR]

Background: The subjective sign of a serious pandemic in human work and life is mathematical neural tinnitus. fNIRS (functional near-infrared spectroscopy) is a new non-invasive brain imaging technology for studying the neurological activity of the human cerebral cortex. It is based on neural coupling effects. This research uses the fNIRS approach to detect differences in the neurological activity of the cerebral skin in the sound stimulation mission in order to better discriminate between the sensational neurological tinnitus. Methods: In the fNIRS brain imaging method, 14 sensorineural tinnitus sufferers and 14 healthy controls listened to varied noise and quiet for fNIRS data collection. Linear fitting was employed in MATLAB to eliminate slow drifts during preprocessing and event-related design analysis. The false discovery rate (FDR) procedure was applied in IBM SPSS Statistics 26.0 to control the false positive rate in multiple comparison analyses. Results: When the ill group and the healthy control group were stimulated by pink noise, there was a significant difference in blood oxygen concentration (P < 0.05), and the healthy control group exhibited a high activation, according to the fNIRS measurement data. The blood oxygen concentration level in the patient group was dramatically enhanced after one month of acupuncture therapy under the identical stimulation task settings, and it was favorably connected with the levels of THI and TEQ scales. Conclusions: Using sensorineural tinnitus illness as an example, fNIRS technology has the potential to disclose future pathological study on subjective diseases throughout time. Other clinical disorders involving the temporal lobe and adjacent brain areas may also be examined, in addition to tinnitus-related brain alterations. [ABSTRACT FROM AUTHOR]

Relaxation dynamics of complex many-body quantum systems trapped into metastable states is a very active field of research from both the theoretical and experimental point of view with implications in a wide array of topics from macroscopic quantum tunnelling and nucleosynthesis to non-equilibrium superconductivity and energy-efficient memory devices. In this work, we investigate quantum domain reconfiguration dynamics in the electronic superlattice of a quantum material using time-resolved scanning tunneling microscopy and unveil a crossover from temperature to noisy quantum fluctuation dominated dynamics. The process is modeled using a programmable superconducting quantum annealer in which qubit interconnections correspond directly to the microscopic interactions between electrons in the quantum material. Crucially, the dynamics of both the experiment and quantum simulation is driven by spectrally similar pink noise. We find that the simulations reproduce the emergent time evolution and temperature dependence of the experimentally observed electronic domain dynamics. Metastable states found in superconductors and charge density wave materials are of fundamental interest. Vodeb et al. study the domain wall dynamics in 1T-TaS2 using scanning tunneling microscopy and a quantum annealer, finding that in both cases the dynamics is driven by spectrally similar noise. [ABSTRACT FROM AUTHOR]

Narrow-linewidth lasers mainly depend on the development of advanced laser linewidth measurement methods for related technological progress as key devices in satellite laser communications, precision measurements, ultra-high-speed optical communications, and other fields. This manuscript provides a theoretical analysis of linewidth characterization methods based on the beat frequency power spectrum and laser phase noise calculations, and elaborates on existing research of measurement technologies. In addition, to address the technical challenges of complex measurement systems that commonly rely on long optical fibers and significant phase noise jitter in the existing research, a short-delay self-heterodyne method based on coherent envelope spectrum demodulation was discussed in depth to reduce the phase jitter caused by 1/f noise. We assessed the performance parameters and testing conditions of different lasers, as well as the corresponding linewidth characterization methods, and analyzed the measurement accuracy and error sources of various methods. [ABSTRACT FROM AUTHOR]

Chaos is prevalent in both nature and science, appearing in data, time series and complex systems. Chaotic systems exhibit numerous uncertainties, akin to noise, which challenge researchers to distinguish or analyze potential underlying patterns or even identify the type of system involved. However, determining the kind of chaotic system is essential, as it enables prediction, synchronization, control, treatment and application. This study employs machine learning to classify chaotic data through a simulation involving three types of research data: Lorenz data, Lorenz combined with Gaussian white noise, Gaussian white noise and pink noise, utilizing six distinct algorithms. The most effective testing results are achieved using Mobilenet, with a classification accuracy of 97.38% and a loss of 0.2680 across these six data types. [ABSTRACT FROM AUTHOR]

This article deals with power supply linear and switching regulators commonly used in various applications for stabilizing an output voltage and ensuring a necessary power input to the load. It describes their basic parameters, performances, advantages, and disadvantages according to their topologies. We design a measurement chain for efficiency evaluation based on power monitors INA219 connected to an embedded system, Arduino UNO. Measurements were focused on evaluation linear regulators MA7805, LM317, switching regulators SZBK07, LM2575, SCW05B-05, and XH-M401. The resulting efficiency of linear and switching regulators was analyzed and errors in the measurement chain were evaluated. The second contribution is an innovative way of carrying out regulator noise estimation using a fast Allan variance method, focused on white noise and flicker noise (bias instability). The main contribution is employing a fast Allan variance method algorithm that dramatically decreases computation time by up to 11 s for 72 million measured (or generated) samples. It enables the analysis of large data sets of various physical quantities (for example, regulator output voltages). [ABSTRACT FROM AUTHOR]

Reinforcement learning (RL), exhibiting outstanding performance in various fields, requires large amounts of data for high performance. While exploration techniques address this requirement, conventional exploration methods have limitations: complexity of hardware implementation and significant hardware burden. Herein, in‐memory RL systems leveraging intrinsic 1/f noise of synaptic ferroelectric field‐effect‐transistors (FeFETs) for efficient exploration are proposed. The electrical characteristics of fabricated FeFETs with low‐power operation capability verify their suitability for neuromorphic systems. The proposed system achieves comparable performance to the conventional exploration method without additional circuits. The intrinsic 1/f noise of the FeFETs facilitates efficient exploration and offers significant advantages: efficiency in hardware implementation and simplicity in adjusting the 1/f noise level for optimal performance. This approach effectively addresses the challenges of conventional exploration methods. The operation mechanism of the exploration method utilizing the 1/f noise is systematically analyzed. The proposed in‐memory RL system demonstrates robustness and reliability to the device‐to‐device variation and the initial conductance distribution. This work provides further insights into the exploration methods of RL, paving the way for advanced in‐memory RL systems. [ABSTRACT FROM AUTHOR]

This document is a letter published in the journal Intensive Care Medicine. The authors conducted a secondary analysis of a study called "Sensopnea 2" to investigate the impact of sensory interventions on thirst in mechanically ventilated patients in the intensive care unit (ICU). The study included 46 patients and found that sensory interventions such as air flow to the face and relaxing music were effective in relieving thirst and dry mouth in these patients. The authors suggest that further research is needed to better understand and manage thirst in ICU patients. [Extracted from the article]

Abstract Previous work assessing the effect of additive noise on the postural control system has found a positive effect of additive white noise on postural dynamics. This study covers two separate experiments that were run sequentially to better understand how the structure of the additive noise signal affects postural dynamics, while also furthering our knowledge of how the intensity of auditory stimulation of noise may elicit this phenomenon. Across the two experiments, we introduced three auditory noise stimulations of varying structure (white, pink, and brown noise). Experiment 1 presented the stimuli at 35 dB while Experiment 2 was presented at 75 dB. Our findings demonstrate a decrease in variability of the postural control system regardless of the structure of the noise signal presented, but only for high intensity auditory stimulation.

A Sigma-Delta modulator (SDM) realized with a fully differential third-order single-loop cascaded integrator feedforward (CIFF) architecture is proposed. A pair of low-frequency chopper switches are nested outside the chopper amplifier to further reduce the residual offset voltage. To reduce the power consumption and ensure linearity, a high-speed dynamic comparator is also used to implement a one-bit quantizer. The proposed architecture and the corresponding functionality are first simulated in MATLAB Simulink at the behavioral level. The results show that the designed modulator has an SNDR of 124.9 dB corresponding to an ENOB of 20.46 bits at a clock frequency of 256 kHz and 312.5 Hz input with a differential-mode voltage of 700 mV sinusoidal waveform. Based on SMIC 180 nm/1.8 V standard CMOS process on the Cadence platform, the subcircuit-level simulation is also performed, while the result shows that the proposed modulator can effectively achieve 115.52 dB SNDR, 18.90-bit ENOB, and 8.40 mW power consumption, which correspond to FoM W and FoM schreier of 0.067 pJ/step and 163.27 dB, respectively. The proposed modulator shows a significant advantage to be applied for high-precision analog-to-digital conversion applications such as high-quality equipment for audio, ECG and EEG signal sensing. [ABSTRACT FROM AUTHOR]

Introduction: This study sought to determine the effect of Occupational Safety and Health Administration (OSHA) compliant noise on auditory health and assess whether pre-noise near infrared (NIR) light therapy can mitigate the effects of noise exposure. Methods: Over four visits, participants (n = 30, NCT#: 03834714) with normal hearing completed baseline hearing health assessments followed by exposure to open ear, continuous pink noise at 94 dBA for 15 min. Immediately thereafter, post-noise hearing tests at 3000, 4000, and 6000 Hz and distortion product otoacoustic emissions (DPOAEs) were conducted along with the Modified Rhyme Test (MRT), Masking Level Difference Test (MLD), and Fixed Level Frequency Tests (FLFT) [collectively referred to as the Central and Peripheral Auditory Test Battery (CPATB)] to acquire baseline noise sensitivity profiles. Participants were then randomized to either Active or Sham NIR light therapy for 30 min binaurally to conclude Visit 1. Visit 2 (=24 and = 48 h from Visit 1) began with an additional 30-min session of Active NIR light therapy or Sham followed by repeat CPATB testing and noise exposure. Post-noise testing was again conducted immediately after noise exposure to assess the effect of NIR light therapy. The remaining visits were conducted following =2 weeks of noise rest in a cross-over design (i.e., those who had received Active NIR light therapy in Visits 1 and 2 received Sham therapy in Visits 3 and 4). Results: Recovery hearing tests and DPOAEs were completed at the end of each visit. Participants experienced temporary threshold shifts (TTS) immediately following noise exposure, with a mean shift of 6.79 dB HL (±6.25), 10.61 dB HL (±6.89), and 7.30 dB HL (±7.25) at 3000, 4000, and 6000 Hz, respectively, though all thresholds returned to baseline at 3000, 4000, and 6000 Hz within 75 min of noise exposure. Paradoxically, Active NIR light therapy threshold shifts were statistically higher than Sham therapy at 3000 Hz (p = 0.04), but no other differences were observed at the other frequencies tested. An age sub-analysis demonstrated that TTS among younger adults were generally larger in the Sham therapy group versus Active therapy, though this was not statistically different. There were no differences in CPATB test results across Active or Sham groups. Finally, we observed no changes in auditory function or central processing following noise exposure, suggestive of healthy and resilient inner ears. Conclusion: In this study, locally administered NIR prior to noise exposure did not induce a significant protective effect in mitigating noise-induced TTS. Further exploration is needed to implement effective dosage and administration for this promising otoprotective therapy. [ABSTRACT FROM AUTHOR]

Global Navigation Satellite Systems (GNSS) enable the determination of station displacements, which are essential to understanding geophysical processes and establishing terrestrial reference frames. Unfortunately, GNSS station position time series exhibit spatially and temporally correlated noise, hindering their contribution to geophysical and geodetic applications. While temporal correlations are commonly accounted for, a strategy for modeling spatial correlations is still lacking. Therefore, this study proposes a diagnosis of the spatial correlations of the white and flicker noise components of GNSS position time series, using the global Nevada Geodetic Laboratory dataset. This analysis reveals different spatial correlation patterns for white and flicker noise and the superposition of three distinct spatial correlation regimes (large-scale, short-scale and station-specific), providing insight into the noise sources. We show, in particular, that about 70% of flicker noise corresponds to large-scale variations possibly attributable to orbit modeling errors. We also evidence an increase in the spatial correlations of white noise at distances below 50 km, most pronounced in the vertical component, where 50% of the white noise appears to be driven by short-scale effects—possibly tropospheric delay mismodeling. [ABSTRACT FROM AUTHOR]

Correlated noise across multiple qubits poses a significant challenge for achieving scalable and fault-tolerant quantum processors. Despite recent experimental efforts to quantify this noise in various qubit architectures, a comprehensive understanding of its role in qubit dynamics remains elusive. Here, we present an analytical study of the dynamics of driven qubits under spatially correlated noise, including both Markovian and non-Markovian noise. Surprisingly, we find that by operating the qubit system at low temperatures, where correlated quantum noise plays an important role, significant long-lived entanglement between qubits can be generated. Importantly, this generation process can be controlled on-demand by turning the qubit driving on and off. On the other hand, we demonstrate that by operating the system at a higher temperature, the crosstalk between qubits induced by the correlated noise is unexpectedly suppressed. We finally reveal the impact of spatio-temporally correlated 1/f noise on the decoherence rate, and how its temporal correlations restore lost entanglement. Our findings provide critical insights into not only suppressing crosstalk between qubits caused by correlated noise but also in effectively leveraging such noise as a beneficial resource for controlled entanglement generation. [ABSTRACT FROM AUTHOR]

A lower bound on the voltage noise power spectrum set by quantum indeterminacy exists in any conducting material. This bound is calculated explicitly for monolayer graphene taking into account graphene pseudospin/valley band structure. It is found to be of the form characteristic of the observed 1 / f γ noise. It is shown that the deviation of γ from unity is a result of the piezoelectric interaction of charge carriers with acoustic phonons. A comparison with the measured 1 / f noise in graphene and graphene-based heterostructures shows that the observed noise intensity is near the quantum bound. It is demonstrated that the recently observed sharp peak in γ at small gate voltages in the field-effect transistors based on graphene/boron nitride heterostructure is well reproduced by the theory, and is to be attributed to the out-of-plane piezoelectric activity in this heterostructure. A simple kinetic model is proposed to describe the effect of the charge carrier trapping on γ. [ABSTRACT FROM AUTHOR]

Flicker noise is a sensitive tool for probing the dynamics of two‐level systems. Herein, this technique is employed to study the dependence of conductance noise on disorder for two versions of amorphous indium oxide films. The disorder in these substances may be tuned by thermal treatment that is manifested by enhanced conductivity. Structural studies reveal that this is mainly due to densification of the material. A similar reduction of volume has been achieved in glasses when subjected to high pressures. Both protocols, pressure and heat treatment, initiate nonequilibrium state that slowly relaxes. This relaxation is reflected in the sample conductivity and its optical transmission as a monotonic change. The magnitude of 1/f noise during these events turns out to fluctuate appreciably following changes in the sample conductance caused by thermal treatment. This may overshadow the tendency of the noise level to increase with disorder. Possible reasons for the fluctuations of noise levels in highly disordered systems are discussed. [ABSTRACT FROM AUTHOR]

Dalbergia pinnata (Lour.) Prain (D. pinnata) is a valuable medicinal plant, and its volatile parts have a pleasant aroma. In recent years, there have been a large number of studies investigating the effect of aroma on human performance. However, the effect of the aroma of D. pinnata on human psychophysiological activity has not been reported. Few reports have been made about the effects of aroma and sound on human electroencephalographic (EEG) activity. This study aimed to investigate the effects of D. pinnata essential oil in EEG activity response to various auditory stimuli. In the EEG study, 30 healthy volunteers (15 men and 15 women) participated. The electroencephalogram changes of participants during the essential oil (EO) of D. pinnata inhalation under white noise, pink noise and traffic noise stimulations were recorded. EEG data from 30 electrodes placed on the scalp were analyzed according to the international 10–20 system. The EO of D. pinnata had various effects on the brain when subjected to different auditory stimuli. In EEG studies, delta waves increased by 20% in noiseless and white noise environments, a change that may aid sleep and relaxation. In the presence of pink noise and traffic noise, alpha and delta wave activity (frontal pole and frontal lobe) increased markedly when inhaling the EO of D. pinnata, a change that may help reduce anxiety. When inhaling the EO of D. pinnata with different auditory stimuli, women are more likely to relax and get sleepy compared to men. [ABSTRACT FROM AUTHOR]