Search results for "frequency [modulation]"

Seksuālās sevis atklāšanās, seksuālā kontakta biežuma un seksuālās apmierinātības saistība pieaugušo vecumā

2021

Seksuālā apmierinātība ir seksuālās veselības un labbūtības sastāvdaļa. Pētījumā tika skatīts kāda saistība pastāv starp seksuālo apmierinātību, seksuālo sevis atklāšanas pakāpi attiecībās un vēlamā seksuālā kontakta biežuma starpību starp partneriem, kā arī to vai pastāv atšķirība attiecībā uz dzimumiem, seksuālo apmierinātību, seksuālo sevis atklāšanas pakāpi attiecībās un vēlamā seksuālā kontakta biežuma starpību starp partneriem un vai atšķirības būs tiem respondentiem, kuriem nav bērni un respondentiem, kuriem ir bērni un viņi dzīvo kopā. Pētījumā piedalījās 182 respondenti, izlasē bija 76,4% (n = 139) sievietes un 23,6% vīrieši (n = 43). 85,7% (n = 156) no aptaujātajiem respondentiem …

Bearing fault detection based on time-frequency representations of vibration signals

2015

To prevent failures of a rolling bearing in the gearbox drive system, acceleration sensors are used to detect fault-related signals of the bearing. It is a big challenge to observe and identify signals caused by bearing defects in the time domain or the frequency spectrum by a conventional Fourier analysis. The time-frequency representation of the fault-related signals implemented by the windowed Fourier transform is studied in this work. It is shown that the fault characteristic frequencies can be clearly identified in the time-frequency spectrum if a fault occurs in the bearing of the gearbox at different speeds. Otherwise, the shaft frequency and its multiples are the main harmonics in t…

Radon measurements in the SE and NE flank of Mt. Etna (Italy)

2007

Abstract Soil Radon has been monitored at two fixed sites located in the northeastern and southeastern flank of Mt. Etna. In this study we report the comparison between in-soil Radon concentration trend recorded in the SE flank and that one recorded in the NE one, where an in-soil Radon detection system is operating since 2001. The aim of this work was to implement the investigation area finding a suitable radon detection site, in the south-east flank of Mt. Etna, in order to better understand possible links between Radon anomalies and volcano dynamic. Radon data collected in NE and SE sites were compared with the volcanic tremor, frequency of occurrence of earthquakes and seismic strain-re…

Incidence of new foci of hepatocellular carcinoma (HCC) in patients who underwent radiofrequency ablation of HCC: Role of multidetector CT

2009

Moving RTS/CTS to the frequency domain: an efficient contention scheme for 802.11ax networks

2019

In this paper, we propose a contention mechanism based on the execution of multiple contention rounds in the frequency domain (ReCHo), which is designed to offer high throughput performance and robustness with respect to imperfect carrier sensing. The main idea is using narrow tones as signalling messages for performing channel access contentions and allowing the Access Point (AP) to echo these signals, in order to extend the sensing capabilities to all the stations associated to the AP. In particular, we refer to the emerging IEEE 802.11ax standard, showing how our scheme can boost performance of random access with respect to the current version of IEEE 802.11ax OFDMA Back-Off (OBO), even …

Examining Online Shopping Services in Relation to Experience and Frequency of Using Internet Retailing

2013

E-shopping has the potential to replace traditional in-store shopping. It is well perceived that information and communication technologies have great impacts on modern society - they are changing how and where we work, shop, and in general terms how we live our lives. In this study, we use a survey instrument to examine the association between experience level with Internet and e-shopping and consumers’ frequency of online purchasing, while considering sex as a passive influencer. We study these relationships in a multinomial logistic regression model that is aimed at online retailers to help them improve their understanding of their consumers’ characteristics and propensity to buy through…

Analysis of Somatosensory Cortical Responses to Different Electrotactile Stimulations as a Method Towards an Objective Definition of Artificial Senso…

2022

Sensory feedback is a critical component in many human-machine interfaces (e.g., bionic limbs) to provide missing sensations. Specifically, electrotactile stimulation is a popular feedback modality able to evoke configurable sensations by modulating pulse amplitude, duration, and frequency of the applied stimuli. However, these sensations coded by electrotactile parameters are thus far predominantly determined by subjective user reports, which leads to heterogeneous and unstable feedback delivery. Thus, a more objective understanding of the impact that different stimulation parameters induce in the brain, is needed. Analysis of cortical responses to electrotactile afference might be an effe…

Convolutional Neural Network Based Sleep Stage Classification with Class Imbalance

2022

Accurate sleep stage classification is vital to assess sleep quality and diagnose sleep disorders. Numerous deep learning based models have been designed for accomplishing this labor automatically. However, the class imbalance problem existing in polysomnography (PSG) datasets has been barely investigated in previous studies, which is one of the most challenging obstacles for the real-world sleep staging application. To address this issue, this paper proposes novel methods with signal-driven and image-driven ways of noise addition to balance the imbalanced relationship in the training dataset samples. We evaluate the effectiveness of the proposed methods which are integrated into a convolut…

Exploring Oscillatory Dysconnectivity Networks in Major Depression During Resting State Using Coupled Tensor Decomposition

2022

Dysconnectivity of large-scale brain networks has been linked to major depression disorder (MDD) during resting state. Recent researches show that the temporal evolution of brain networks regulated by oscillations reveals novel mechanisms and neural characteristics of MDD. Our study applied a novel coupled tensor decomposition model to investigate the dysconnectivity networks characterized by spatio-temporal-spectral modes of covariation in MDD using resting electroencephalography. The phase lag index is used to calculate the functional connectivity within each time window at each frequency bin. Then, two adjacency tensors with the dimension of time frequency connectivity subject are constr…

Data from: Negative frequency-dependent selection of sexually antagonistic alleles in Myodes glareolus

2011

Sexually antagonistic genetic variation, where optimal values of traits are sex-dependent, is known to slow the loss of genetic variance associated with directional selection on fitness-related traits. However, sexual antagonism alone is not sufficient to maintain variation indefinitely. Selection of rare forms within the sexes can help to conserve genotypic diversity. We combined theoretical models and a field experiment with Myodes glareolus to show that negative frequency-dependent selection on male dominance maintains variation in sexually antagonistic alleles. In our experiment, high-dominance male bank voles were found to have low-fecundity sisters, and vice versa. These results show …