Impulse Frequency Research Articles

Cultural values and ethnic identity are important considerations in the link between emotion dysregulation and loss of control eating in Asian/Asian American men

ObjectivePreliminary data suggest that Asian/Asian American report among the highest rates of loss of control (LOC) eating, yet the psychosocial and sociocultural correlates of LOC eating are currently understudied. The present study sought to examine the link between emotion dysregulation and LOC eating in Asian/Asian American men. Adherence to traditional Asian cultural values and ethnic identity were evaluated as potential moderators. Methods266 Asian/Asian American men (Mage = 24.4 ± 3.6y; MBMI = 24.2 ± 5.6 kg/m2) participated in the current study and completed an online survey. ResultsNegative binomial regression models generally supported the positive link between emotion dysregulation and LOC eating in Asian/Asian American men. However, lack of emotional awareness when distressed was found to be significantly and inversely associated with LOC eating frequency. Adherence to Asian cultural values moderated the association between emotional impulsivity and LOC eating frequency; this link was positive among those with low adherence to Asian values, and negative among those with high adherence to Asian values. Exploration of one's ethnic identity moderated the link between emotional awareness when distressed and LOC eating frequency; the association was flat among men with low exploration of their ethnic identity, and inverse among those with high exploration of their ethnic identity. DiscussionAlthough mechanistic and prospective studies are needed, these findings provide support for the affect regulation model of LOC eating in Asian/Asian American men and suggest that there are culture-specific factors that may be relevant to the development and/or maintenance of this disordered eating behavior.

Study on static and dynamic behavior of jute/sisal fiber reinforced epoxy composites

In this work, the mechanical characteristics and free vibration behavior of Jute, Sisal and hybrid Sisal/Jute epoxy composites were investigated. A free Vibration test was conducted using the Impulse Frequency response test under a free-free boundary condition. Plain weave Jute and Sisal fabric were used in the ratio of 60:40. The hand fabrication method was used for fabrication, followed up with compression under the compression molding method. Alkaline treatment was carried out before fabrication to improve the interfacial strength between the matrix and fiber. Mechanical properties like Tensile strength and flexural strength are found to be higher for Hybrid Sisal/Jute than the Jute and Sisal polymer composites. Reduced resonant amplitude in the FRF shows Hybrid laminate has a good damping tendency than other considered composites.

Spinal cord stimulators and implications for anaesthesia

Spinal cord stimulators and implications for anaesthesia

Frequency-Dependent Reaction of the Triceps Surae Muscle of the Mouse During Electromyostimulation.

The difference in the efficacy of altered stimulation parameters in whole-body-electromyostimulation training (WB-EMS) has hardly been examined. Higher impulse frequencies (>50 Hz) might be most adequate for strength gains because of the force frequency relationship (FFR), which describes a greater force production by increasing the applied frequency. Frequencies below this value, however, also seem to have positive influences on muscle strength increases. Therefore, the aim of this study was to analyze possible muscle length changes to different stimulation frequencies of the dissected mouse triceps surae muscle. A bending rod transducer was used to measure and compare changes in muscle lengths at different frequencies in relation to the initial length in the prepared muscle. We found significant differences between the muscle shortening at different frequencies (p < 0.001). At 20 Hz the largest muscle shortening was observed (20 Hz = 3.32 ± 2.06, 60 Hz = 0.77 ± 0.58, 85 Hz = 0.32 ± 0.29, 100 Hz = 0.31 ± 0.29). From a frequency of 60 Hz, the muscle shortening decreased progressively, at stimulation frequencies above 60 Hz the lowest shortenings were recorded. The results demonstrate a different behavior of the isolated triceps surae muscle of the mouse in an ex vivo environment. Even if there is no FFR in this investigation, the results indicate a higher metabolic demand using higher frequencies in electromyostimulation, despite the experimental execution in ex vivo design. Therefore, future studies should take this faster fatigue into account when drawing up training protocols in order to counteract possible frequency modulations.

Pulmonary stretch receptor activity during partial liquid ventilation with different pressure waveforms

BackgroundThe aim of the present study was to investigate pulmonary stretch receptor activity (PSR) under different peak inspiratory pressures (PIPs) and inspiratory pressure waveforms during partial liquid (PLV) and gas ventilation (GV). MethodsPSR instantaneous impulse frequency (PSRfimp) was recorded from single fibers in the vagal nerve during PLV and GV in young cats. PIPs were set at 1.2/1.8/2.2/2.7 kPa, and square and sinusoidal pressure waveforms were applied. ResultsPSRfimp at the start of inspiration increased with increasing PIPs, and was steeper and higher with square than with sinusoidal waveforms (p < 0.05). Total number of impulses, peak and mean PSRfimp were lower during PLV than GV at the lowest and highest PIPs (p < 0.025). Time to peak PSRfimp was shorter with square than with sinusoidal waveforms at all pressures and ventilations (p < 0.005). Irrespective of waveform, lower PIPs yielded lower ventilation during PLV. ConclusionAs assessed by PSRfimp, increased PIPs do not expose the lungs to more stretching during PLV than during GV, with only minor differences between square and sinusoidal waveforms.

Estimating Digital Watermark Synchronization Signal Using Partial Pixel Least Squares

To read a digital watermark from printed images requires that the watermarking system read correctly after affine distortions. One way to recover from affine distortions is to add a synchronization signal in the Fourier frequency domain and use this synchronization signal to estimate the applied affine distortion. If the synchronization signal contains a collection of frequency impulses, then a least squares match of frequency impulse locations results in a reasonably accurate linear transform estimation. Nearest neighbor frequency impulse peak location estimation provides a good rough estimate for the linear transform, but a more accurate refinement of the least squares estimate is accomplished with partial pixel peak location estimates. In this paper we will show how to estimate peak locations to any desired accuracy using only the complex frequencies computed by the standard DFT. We will show that these improved peak location estimates result in a more accurate linear transform estimate. We conclude with an assessment of detector robustness that results from this improved linear transformation accuracy.

Adaptive Narrow-Band Interference Suppression and Performance Evaluation Based on Code-Aided in GNSS Inter-Satellite Links

In this paper an adaptive narrow-band interference (NBI) suppression scheme based on a code-aided technique in the global navigation satellite system inter-satellite links (ISLs) is proposed. Unlike the commonly used infinte impulse response (IIR) notch filter and frequency domain filtering, the code-aided technique does not require interference detection or fast Fourier transforms, and the adaptive performance is better. We introduce the principle and implementation of code-aided technique, and the concept of interference influence coefficient is proposed to evaluate the influence of residual interference on the carrier-to-noise ratio (CNR) at the receiving end. Through simulation and by combining the tracking CNR after antijamming, the optimal antijamming parameters and scheme are obtained. Meanwhile, we analyze the relationship between the loss of CNR caused by residual interference and the interference influence coefficient. The final results of the bit error rate (BER) and ranging error in ISLs indicate that the adaptive interference suppression scheme based on the code-aided technique can effectively suppress NBI and ensure the reliability of ISL communications. In the case where the pseudo code rate is 10.23 MHz and the BER does not exceed $1 \times {10^{ - 5}}$ , for the NBI with a bandwidth of 2 MHz, the maximum interference-to-signal ratio (ISR) that can be suppressed by the proposed scheme is 40 dB. For the NBI with a bandwidth of 1 MHz, the maximum ISR that can be suppressed is 55 dB, and for single frequency interference, the maximum ISR that can be suppressed is 75 dB.

A Highly Conductive 3D Cardiac Patch Fabricated Using Cardiac Myocytes Reprogrammed from Human Adipogenic Mesenchymal Stem Cells.

The objective of this study was to bioengineer 3D patches from cardiac myocytes that have been reprogrammed from human adipogenic mesenchymal stem cells (hADMSCs). Human adipogenic mesenchymal stem cells (hADMSCs) were reprogrammed to form cardiac myocytes using transcription factors ETS2 and MESP1. Reprogrammed cardiac myocytes were cultured in a fibrin gel to bioengineer 3D patch patches. The effect of initial plating density (1-25 million cells per patch), time (28-day culture period) and treatment with 1μM isoproterenol and 1μM epinephrine were evaluated. 3D patches were fabricated using cardiac myocytes that have been reprogrammed from hADMSCs. Based on optimization studies, it was determined that 10 million cells were needed to bioengineer a single patch, that measured 2 × 2cm2. Furthermore, 3D patches fabricated 10 million cells were stable in culture for up to 28 days. Treatment of 3D patches with 1μM isoproterenol and 1μM epinephrine resulted in an increase in the electrical properties, as measured by electrical impulse amplitude and frequency. An increase in the expression of mTOR, KCNV1, GJA5, KCNJ16, CTNNT2, KCNV2, MYO3, FOXO1 and KCND2 was noted in response to treatment of 3D patches with isoproterenol and epinephrine. Based on the results of this study, there is evidence to support the successful fabrication of a highly functional 3D patches with measurable electrical activity using cardiac myocytes reprogrammed from hADMSCs. 3D patches fabricated using optimal conductions described in this study can be used to improve the functional properties of failing hearts. Predominantly, in case of the infarcted hearts with partial loss of electrical activity, the electrical properties of the 3D patches may restore the electrical activity of the heart.

Novel predictive features using a wrapper model for rolling bearing fault diagnosis based on vibration signal analysis

In modern diagnostic approaches, the key step consists in generating the features related to fault type and severity. In fact, the generated features should be able to help the classifier to determine the health condition of the monitored system based on the measured signal. In this paper, in order to make an effective diagnosis about the rolling-element bearing failure, novel generated features that can maintain the physical meaning of the extracted vibration signal, while identifying its relationship to rolling bearing damage, are proposed using a wrapper model. For this purpose, based only on the Most Impulsive Frequency Bands (MIFBs) of the measured vibration signals for many bearing conditions, 33 feature parameters are proposed. Using a wrapper scheme, these parameters can be reduced until a set of them are found improving the efficiency of the diagnostic approach. The effectiveness of the proposed predictive features is analyzed by comparing it with some related works using many testing data for several bearing conditions. The experimental results reveal that the proposed procedure has obtained a high level of accuracy of 99.83%.

Combination Therapy for Treatment of Spasticity in Stroke Patients: A Case Study.

Background and purpose: Spasticity is a disorder of sensory-motor control that appears as an effect of a lesion in the upper motor neuron and demonstrates sustained or intermittent unintentional muscle activation. Many treatment interventions exist to treat spasticity, and in this study, three of them were combined: vibration, static positioning and transcutaneous nerve stimulation (TENS). Evidence exists regarding the application of each intervention per se, but not in combination. Hence, the aim of the study is to present an innovative treatment approach for spasticity and show the effects it produced on one patient. Methods: The study was a case report. The subject was a 31-year-old male patient who had ischemic stroke a year ago. He demonstrated severe plantar flexion of the left foot due to spasticity. There was a baseline assessment and measurement, one on the end of the intervention (10th week) and a follow-up 8 months after it. Assessment and measurement tools: a dynamic gait analysis on the treadmill by Zebris FDM-T system, electromyography testing (F-wave parameter and stretch reflex activity), the Modified Ashworth Scale (MAS), a standard goniometer, the Motricity index (MI) leg score and a pain dichotomous when stretching and while at rest. Intervention: The intervention lasted 10 weeks, 5 days per week for 30 minutes. The patient was standing on a 30-degree-inclination wedge. The wedge was positioned on a whole-body vibrator set to vibrate with 91Hz of frequency and 1.0mm amplitude. TENS was offered through surface electrodes which were placed on the tibialis anterior and triceps surae muscles, along the sural nerve (impulse frequency: 100Hz, pulse width: 250μs, intensity: 30mA). Results: The range of motion and the MI was increased and the swing-phase of the right foot as well as the standing-phase of the left foot were increased an hour after the intervention. The results were slightly diminished a day and a week after the intervention but a statistically significant improvement still remained. Conclusion: Combination therapy intervention could offer an alternative for treating spasticity. Further studies are needed to establish a treatment protocol and maybe combine other spasticity-centered treatment modalities in order to produce new interventions.

Influence of the Load on the Impulse Frequency Response Approach Based Diagnosis of Transformer’s Inter-Turn Short-Circuit

Frequency Response Analysis (FRA) is an Off-line condition monitoring technique for the transformers and is successful, in diagnosing mechanical faults and inter-turn short-circuits. Only limited literature is available for On-line FRA works, and the effect of the transformer’s load on the fault diagnosing capability of FRA has not yet been analysed. Motivated by this research gap, an experimental investigation was done to analyze the effect of load on IFRA based inter-turn short-circuit diagnosis. A single-phase 1 kVA, 240V/240 V transformer supplying R and R-L loads and a three-phase 5 kVA, 440 V/440 V transformer supplying an induction motor at various load levels were tested. Inter-turn short-circuits were emulated in their windings and, the effectiveness of IFRA in diagnosing the same was investigated. Comparisons were made between the frequency response of the loaded transformers in their healthier conditions and emulated fault conditions, based on the transfer function plots and the statistical parameters. Investigations reveal that the loads alter the useful spectrum of IFRA. The frequency response of the healthier transformer itself varies based on the transformer’s load and necessitates a careful focus on the sensitive frequency spectra for effective inter-turn short-circuit diagnosis in loaded transformers.

Research on airplanes engines dynamic processes with modern acoustic methods for fast and accurate diagnostics and safety improvement

The issues of monitoring the processes of combustion and fuel injection in a turbojet engine of a multi-purpose aircraft in real conditions of its use with the use of selected characteristics and measures of acoustic signal processes have been described in the paper. The aim is early detection of sources and parametric assessment of the intensity of negative changes in the above-mentioned main processes and in the components of the aircraft propulsion system, taking into account contemporary criteria for improving the safety of the implementation of the aviation task. Appropriate functional relations have been built for acoustic characteristics that are a response to specific sources of changes in the creation of a combustible mixture and its combustion process, which can be used in their continuous diagnostics, in accordance with the criteria of the highest operational efficiency of the thermodynamic and mechatronic system, including ensuring safety improvement. Operational indicators of the highest sensitivity for both processes have been linked to the particular acoustic impulse and energy parameters and frequency spectra, for which specified energy quantum is transferred by means of vibrating particles. The results demonstrate the proposed method assures early and accurate diagnostics for engine dynamic characteristics. The built procedures for combustion and injection projections in the acoustic discrete and continuous representations, both in process value and frequency domains, make the obtained findings valid for on-board fault-diagnosis system building.

Analysis of aperiodicity in artistic Noh singing voice using an impulse sequence representation of excitation source.

Aperiodicity in the voice source is caused by changes in the vocal fold vibrations, other than the normal quasi-periodicity and the turbulence at the glottis. The aperiodicity appears to be one of the main properties that is responsible for conveying the emotion in artistic voices. In this paper, the feasibility of representing the excitation source characteristics in artistic (Noh) singing voice by an impulse-like sequence in the time domain is examined. The impulses at the glottal closure instants contribute to the major excitation of the vocal tract system. The sequence of such impulses produces harmonics of the fundamental frequency in the spectrum. The amplitude variation or amplitude modulation (AM) of these impulses in the sequence contributes to the aperiodicity in the excitation, and can result in appearance of subharmonics in the spectrum. The variation in the impulse intervals or frequency modulation (FM) can also contribute to the aperiodicity in the excitation. The aperiodic component of the excitation in the Noh voice is examined in the impulse-like sequence derived from the signal using the single frequency filtering analysis. The effects of aperiodicity are explained for synthetic AM and FM sequences of impulses using spectrograms and saliency plots.

Detection Technique of Partial Discharges at Impulse Voltage with Appropriate Filter Settings for Signal Separation

Due to the increased utilization of electric converters feeding rotating high voltage motors, their insulation is subject to transient impulse and high frequency oscillating voltages. In corresponding life time experiments with repetitive oscillating impulse voltage at winding insulation samples, higher life time coefficients were observed than known from previous investigations and operational experience. In order to understand the discharge and aging phenomena, the purpose of this work is the secure detection of partial discharges in solid and solid–air insulation types for transient impulse voltage stress by applying an adequate partial discharge (PD) measurement technique to future life time experiments. It is shown that partial discharges under impulsive voltages can be detected with conventional measuring equipment using broadband shunts, as well as inductive antennas. It becomes apparent that a precise voltage source, a precise shunt, as well as a high resolution oscilloscope are mandatory for reliable current measurement results. As a part of the analysis of the measurement data, it is shown that partial discharges can be distinguished from the displacement current caused by impulse voltages in a capacitive insulation material, as well as noise and disturbance from the measurement environment. As a first approach, a high order bandpass filter is applied in order to gain sound signals for future automated signal separation.

Toward Higher Performance for Channel Estimation With Complex DnCNN

In the letter, we propose to estimate uplink channel in urban 3-D MIMO systems utilizing denoising convolutional neuron networks (DnCNNs), which is recently proposed and has succeeded in tackling with image denoising tasks in computer vision. To process the complex numbers in channel estimation (CE), based on complex DnCNN (CDnCNN), a variant of DnCNN, we propose the simplified DnCNN (S-DnCNN) CE. S-DnCNN CE includes two major parts. In the first part, the channel frequency impulses are rearranged to form feature maps. In the second part, considering the practical latency constraints, we provide the S-DnCNN structure and fast training/testing (FT) methods. The practical 3-D MIMO channel model is used in the simulation. The results show that S-DnCNN CE outperforms traditional methods and CDnCNN-based ChannelNet. Besides, our FT S-DnCNN CE greatly reduces the time complexity compared to ChannelNet.

Radiosensitivity of morphoenzymological structural elements of the jejunum mucous membrane in chronodynamics of the impact of electromagnetic fields impulses

Results of numerous researches have revealed that most sensitive to electromagnetic radiations are the nervous, endocrine and cardiovascular systems of an organism, however, the analysis of literary data confirms also the direct involvement of organs of the intestinal system in physiological, and not seldom, and the pathological program of the response of an organism to the action of extreme factors. In the experiment executed on white laboratory male rats by ourselves there was studied the grade of the radiosensitivity of morphoenzymological structural elements of jejunum mucous membrane after 5, 7 and 10 months of chronic influence of electromagnetic fields impulses with a density of induced currents 0.37; 0.7; 0.8; 2.7 kA/m and frequency of impulses 50, 100 and 500 in a week irrespective of their divisibility of ultrashort duration of 15 a 40 ns. Scientific value and novelty of results is concluded in revealed multiple linear relationships between indices of electromagneticfields (duration of the impact, density of induced currents, periodicity of impulses and the dynamics of the studied indices of a morphofunctional condition of a jejunum mucous membrane). Besides that, there was found the critical population to indices of electromagneticfields impulses parameters - the jejunum mast cells differing in hypersensitivity and dependence on duration of influence and density of induced currents revealed, at that their bioeffects were unidirectional.

Global Exponential Stability of Impulsive Delay Systems With Flexible Impulse Frequency

We establish global exponential stability theorems for impulsive delay differential systems with flexible impulse frequency. Since impulses often occur instantaneously, intermittently, or irregularly, it is possible that impulses occur with high frequency in some time-domains, and with low frequency in some others, which means that it is not always reasonable for existing results to make assumptions on common lower (or upper) bound of impulsive intervals in the analysis of stability. We propose a new approach which is based on impulsive control theory, the method of auxiliary functions, and linear matrix inequality technique to solve the problem of flexible impulse frequency. This paper mainly focuses on the stability analysis from the impulsive perturbations point of view, that is, the system subjects to destabilizing impulses. In this category, our developing results admit the existence of irregular impulsive intervals. It shows a fact that even there are some time intervals with high impulse frequency, the stability of delay system can still be guaranteed provided that the impulsive intervals with low impulse frequency satisfy certain conditions. Two numerical examples and their simulations are given to show the effectiveness of the proposed approach.

The Numerical Research on Rock Breaking and Rising Mechanism of Rotary-Percussive Drilling

In this paper, the numerical simulation is used to study the rising mechanism of rotary-percussive drilling, which is under the combination of rotary cutting and axial impact. The main objective of the present work is to compare and investigate the breaking process of rock element and the motion state of drilling bit under the conventional drilling and rotary punching drilling. Additionally, the single-factor analysis is used to analyze the effects of impulse load, impulse frequency, rotary speed and formation hardness on rock breaking efficiency and acceleration effect of rotary percussion drilling. Through the investigation, it is found that there are more areas of tension stress breakage in rock elements under rotary-percussive drilling. Rotary percussion drilling can effectively alleviate the stick–slip vibration of drilling bit. At the same time, the relationship between the average penetration rate of the bit and the impulse load, impulse frequency, rotary speed and formation hardness is shown. The results of the study will be beneficial to provide some theoretical reference for the development of tools and the selection of working parameters of rotary-percussive drilling technology, as well as for the drilling methods of deep wells and hard rocks.

Some recent results of analysis and control for impulsive systems

Since impulsive control has less conservation in the analysis of dynamical behaviors, a surge of attention has been paid on the study of impulsive control systems. This paper is dedicated to review some recent developments of impulsive control theory. Some fundamental theory on impulsive control systems and some very recent interesting results are reviewed and addressed. Based on the characteristics of impulsive control systems, we summarize three fundamental factors for the design of impulsive controllers, namely, the impulsive strength, the impulsive frequency and the impulsive instant. Then a systematic account of useful stability analysis methods are introduced, and these methods provide researchers a well-organized tool box to learn the impulsive control systems. Moreover, as a vital aspect, the effects of delays on impulsive systems are discussed. Finally, some potential developments and further work on impulsive control systems are briefly presented and discussed.

The Case for Global Positioning System Arcing and High Satellite Arc Rates

The Global Positioning System (GPS) satellites arc into the space environment. Evidence for this consists of undispersed impulsive radio frequency signals are shown in the dual-frequency RF receivers, that are on-board all GPS satellites, with high rates that track the charging electron environment, detection of appropriate amplitude short-timescale pulses from GPS satellites at 327 and 430 MHz with the Arecibo 305-m Gordon radiotelescope that do not appear in off-source scans, and arcing on laboratory GPS-like solar arrays at voltages similar to those inferred from GPS arc thresholds. In addition, GPS satellites (up to the Block IIRM) have power degradation (in excess of that expected from radiation) of about 1.5% per year. This degradation is primarily in the short-circuit current, consistent with contamination on the solar array cover glasses, which was detected by a thermal monitor on one GPS satellite solar array, and to be consistent with the power degradation observed on a highly arced GPS-like laboratory solar array if extrapolated to GPS undispersed event rates. The GPS arc rates required for solar array contamination and consistent with the onboard observed event rates are very high, in fact, higher than the rates measured previously on SCATHA, CTS, and other satellites. It is conjectured that the effects of these arcs on satellite power systems have been routinely prevented by highly filtering the power system and antenna response, that most satellites have had no way to detect arcing, and that most power losses up to the present time have been ascribed to radiation damage. Results of new optical and radio-frequency radio frequency observations of satellite arcing are discussed, as well as laboratory measurements confirming the high arc rates and their consequences.