John F. Dunne · Cytometry · 1991
Flow cytometric hardware and procedures were developed to continuously analyse and to sort a particular time window in a kinetic response. The technique uses balanced air pressure to drive a stimulus-bead mixture from a vial to a t-junction where it mixes passively with cells. The t-junction is distanced from the flow cell and air pressure regulated so that the stimulation occurs at a fixed and adjustable time before the cells are interrogated by the laser beam. Practical applications of the device demonstrate utility with cells whose responses are seen in seconds or minutes. The device is easily implemented on any sorting flow cytometer.
Cited by 22Open access
Metin Bayram And · 2008
We propose an extension of Thomson's multiple window spectrum estimation for stationary random processes to the time-varying spectrum estimation of non-stationary random processes. Unlike previous extensions of Thomson's method, in this paper we identify and utilize optimally concentrated window and wavelet functions for the timefrequency and time-scale planes respectively. Moreover, we develop a statistical test for detecting and extracting chirping line components.
Cited by 0
F. Cakrak, Patrick J. Loughlin · IEEE Transactions on Signal Processing · 2001
A multiwindow method for generating a time-varying spectrum of nonstationary signals is presented The time-varying spectrum is computed from an optimally weighted average of multiple orthogonal windowed spectrograms. The weights are determined using linear least squares estimation with respect to a reference time-frequency distribution. Examples are provided, with performance criteria measures, to demonstrate and quantify the effectiveness of the method.
Cited by 51
Enrico Amico (527269), Iulia Martina Bulai (11824481) · Figshare · 2021
<p><b>A</b>. First row, four different dynamic Covidomes corresponding to 10th of March, 4th of May, 14th of October and 4th of November, respectively (dashed lines). Second row, time series for the mean of the upper triangular dynamic Covidomes for three different Italian areas (first column: hospitalized individual with symptoms time series; second column: new positives; note that the dynamic Covid connectivity snapshots have different colorbar range for the two time series). <b>B</b>. Nodal Eigenvector centrality of the Dynamic Covidomes, averaged across the three Italian areas (first column: hospitalized individual with symptoms time series; second column: new positives).</p>
Cited by 0Open access
Hyeon Gyu Kim · Lecture notes in electrical engineering · 2014
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Roger Bakeman, Vicenç Quera · Cambridge University Press eBooks · 2011
The phrase, sequential analysis – which appears in the title of this book as well as earlier ones (Bakeman & Gottman, 1997; Bakeman & Quera, 1995a) – admits to more than one meaning. In the context of microbiology, it can refer to the description of genetic material. In the context of statistics, it can mean sequential hypothesis testing – that is, evaluating data as they are collected and terminating the study in accordance with a predefined stopping rule once significant results are obtained (Siegmund, 1985).
Cited by 0
Boris Puterka, Juraj Kačur · 2018
In this paper we present time analysis results of speech emotion recognition using convolutional neural network architecture and spectrograms as a speech features. Analyses were performed on model with two convolutional layers followed by pooling layer, and one fully-connected layer followed by dropout and softmax layer on the output. On this model we analyzed time characteristics of speech signal represented by spectrograms. The aim of our work was to find relation between duration of speech signal and the recognition rate of seven basic emotions. It was discovered that speech length is important and naturally the accuracy is growing with the length of analyzed window, however over approximately 1.2 seconds the growth becomes rather mild.
Cited by 11
John Jelonnek, K. Schuenemann · OSTI OAI (U.S. Department of Energy Office of Scientific and Technical Information) · 1995
In a rigorous time-domain analysis of gyrotrons, a model expansion of the time-harmonic electromagnetic field inside the cavity is used. To apply it in time-domain, a Fourier transform is performed. This requires a large amount of computer resources. It is shown how to compute the time-dependent electromagnetic field by the complex-valued impulse responses of the cavity eigenfunctions. Numerical results for a 150 GHz TE{sub 0.3} gyrotron are presented including window reflections from distances to the cavity output which are very long compared to the operating wavelength.
Cited by 2
Nadja Althaus (596952), Denis Mareschal (596953) · Figshare · 2015
<p>The main analysis focuses on initial responses (1–1000 ms) to the visual stimulus, which reflect categorization processes.</p>
Cited by 0Open access
Runyu Li (13832671), Fuguo Cao (13832668) · Figshare · 2023
Cited by 0Open access
Ahmed Babu Shahas VP · International Journal of Multidisciplinary Research in Science, Engineering and Technology. · 2025
Construction projects often face delays due to complex interconnections, unexpected events, and poor planning. These delays lead to requests for more time (called extensions of time or EOT) and extra costs (known as prolongation costs). Dealing with prolongation cost claims is one of the trickiest parts of managing construction contracts because it directly affects how much money the project makes and how cash flows. Contractors frequently run into problems like design issues and change orders. This research aims to create a clear, step-by-step approach for spotting, evaluating, and prolongation cost claims related to EOT. It focuses on standard contract types, especially those based on FIDIC agreements. The researchers looked at existing studies, real-world cases, and created theoretical models. From this, they suggest a standard method that combines ways to analyze delays, assess cost impacts, and meet documentation requirements. The study emphasizes how important it is to keep accurate, real-time records, use fair methods to analyze delays, and pay attention to specific contract terms when making claims. These findings should help improve how claims are managed and make it easier to fairly settle disputes about time and money in construction projects.
Cited by 0Open access
J. Pytel, Béla Büki · Clinical Otolaryngology · 1995
We have developed a technique for off-line analysis of transient otoacoustic emissions. The correlation of two curves was calculated in a moving time-window of 1 ms time sections. By this method it is possible to recognize high-correlation parts, time sections with low correlation, and thus the duration of the emission can be determined. The mean absolute duration of transiently evoked otoacoustic emissions in 36 normal ears was 15.1 +/- 0.69 ms (mean +/- SE). The duration was significantly shorter (9.34 +/- 0.43) in 75 ears with different grades of sensorineural hearing loss. The breakdown of this group into sub-groups according to the width of the high frequency band with elevated threshold showed a correlation between the severity of the hearing loss and the absolute duration.
Cited by 3
Kai Li, Heinz Rüdiger, Tjalf Ziemssen · Frontiers in Neurology · 2019
Spectral analysis of heart rate variability (HRV) is a valuable tool for the assessment of cardiovascular autonomic function. Fast Fourier transform and autoregressive based spectral analysis are two most commonly used approaches for HRV analysis, while new techniques such as trigonometric regressive spectral (TRS) and wavelet transform have been developed. Short-term (on ECG of several minutes) and long-term (typically on ECG of 1-24 h) HRV analyses have different advantages and disadvantages. This article reviews the characteristics of spectral HRV studies using different lengths of time windows. Short-term HRV analysis is a convenient method for the estimation of autonomic status, and can track dynamic changes of cardiac autonomic function within minutes. Long-term HRV analysis is a stable tool for assessing autonomic function, describe the autonomic function change over hours or even longer time spans, and can reliably predict prognosis. The choice of appropriate time window is essential for research of autonomic function using spectral HRV analysis.
Cited by 195Open access
Zoran Cvetković · 2002
Weyl-Heisenberg frames are the tool for short-time Fourier analysis. These are generated from a prototype window function using translation on a rectangular grid in the time-frequency plane. Particularly appealing Weyl-Heisenberg frames are those which are tight as they allow for signal representations analogous to orthonormal expansions and have good numerical stability properties. Designing the window of a tight Weyl-Heisenberg frame requires optimization of the frequency characteristics of the window, usually some form of frequency selectivity, under a set of nonlinear constraints. For long windows this can be a formidable task, if not infeasible. We propose a new filter design method based on expansions with respect to prolate spheroidal sequences. The advantages of this new method are more and more pronounced as the redundancy of the frame increases. These advantages pertain to a reduction in computational complexity and the ability to describe good and long windows with a few parameters.
Cited by 0
Juan L. Navarro-Mesa · Acceda (Universidad de Las Palmas de Gran Canaria) · 1995
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Hasan A. Bedel, Irmak Şıvgın, Onat Dalmaz et al. · arXiv (Cornell University) · 2022
Deep-learning models have enabled performance leaps in analysis of high-dimensional functional MRI (fMRI) data. Yet, many previous methods are suboptimally sensitive for contextual representations across diverse time scales. Here, we present BolT, a blood-oxygen-level-dependent transformer model, for analyzing multi-variate fMRI time series. BolT leverages a cascade of transformer encoders equipped with a novel fused window attention mechanism. Encoding is performed on temporally-overlapped windows within the time series to capture local representations. To integrate information temporally, cross-window attention is computed between base tokens in each window and fringe tokens from neighboring windows. To gradually transition from local to global representations, the extent of window overlap and thereby number of fringe tokens are progressively increased across the cascade. Finally, a novel cross-window regularization is employed to align high-level classification features across the time series. Comprehensive experiments on large-scale public datasets demonstrate the superior performance of BolT against state-of-the-art methods. Furthermore, explanatory analyses to identify landmark time points and regions that contribute most significantly to model decisions corroborate prominent neuroscientific findings in the literature.
Cited by 3Open access
J. H. Majors · Scilight · 2018
To address the unique complexities of simulating surface plasmon polariton signals, where frequency domain analysis is suboptimal, an FDTD approach reveals pulse dynamics in the time domain.
Cited by 0
Tianyuan Tan, Wenjuan Chen, Kaipei Liu et al. · Journal of Modern Power Systems and Clean Energy · 2016
The signal spectral leakage and fence effect are prone to take place during the power harmonic analysis by fast fourier transform (FFT) under asynchronous sampling. The inhibiting ability of classical window functions is restricted by side-lobe behaviors. A new type window function called time domain mutual-multiplication window, is obtained by multiplication operation of several window functions. A novel approach of harmonic analysis is developed through analyzing performances of main-lobe and side-lobe of the new window. Simulation results show that the time domain mutual-multiplication window can significantly suppress frequency spectral leakage and improve the accuracy of harmonic parameter estimation.
Cited by 8Open access
Jill Chorney, Ana M. García, Kristoffer S. Berlin et al. · Journal of Pediatric Psychology · 2010
Sequential analysis is a technique that is useful to pediatric psychologists who are interested in contingencies among data collected over time.
Cited by 53Open access
Hasan A. Bedel, Irmak Sivgin, Onat Dalmaz et al. · Medical Image Analysis · 2023
Cited by 101