Results 71 to 80 of about 5,052 (252)

Detection of Pipeline Leaks Using Fractal Analysis of Acoustic Signals

Fractal and Fractional
In this paper, the possibility of using monofractal and multifractal analysis of acoustic signals of pipelines to detect leaks is considered. An experimental stand has been created to study the fractal characteristics of acoustic signals of pipelines ...
Ayrat Zagretdinov, Shamil Ziganshin, Eugenia Izmailova, Yuri Vankov, Ilya Klyukin, Roman Alexandrov   +5 more
doaj   +1 more source

Last‐minute coordination: Adapting to demand to support last‐mile operations

Journal of Operations Management, Volume 71, Issue 2, Page 176-194, March 2025.
Abstract In the highly competitive e‐commerce industry, customer‐facing warehouses are crucial as the “order penetration points” for e‐commerce last‐mile operations. This research examines how warehouses use last‐minute coordination, an unstructured mechanism, to ensure sufficient inventory at the order penetration points. Previous research has focused
Kedong Chen, Hung‐Chung Su, Kevin Linderman, William Li   +3 more
wiley   +1 more source

Detrended fluctuation analysis of traffic data

CoRR, 2008
Different routing strategies may result in different behaviors of traffic on internet. We analyze the correlation of traffic data for three typical routing strategies by the detrended fluctuation analysis (DFA) and find that the degree of correlation of the data can be divided into three regions, i.e., weak, medium, and strong correlation.
Xiaoyan Zhu, Zonghua Liu, Ming Tang
openaire   +2 more sources

A Hybrid RF Coil for Whole‐Brain Imaging in Non‐Human Primates at 7 T

Magnetic Resonance in Medicine, EarlyView.
ABSTRACT Purpose Ultra‐high field MRI (≥ 7 T) offers unprecedented potential for mapping non‐human primate (NHP) brain function. However, complex electromagnetic systems are required to meet the challenges of UHF imaging and the mechanical demands of awake NHP studies.
Elias Djaballah, Éric Giacomini, Paul‐François Gapais, Michel Luong, Alexis Amadon, Qi Zhu   +5 more
wiley   +1 more source

Ultrafast fMRI Detects Age‐Related Changes in Harmonics of Cardiac Pulsations in the Brain at 7 T

Magnetic Resonance in Medicine, EarlyView.
ABSTRACT Purpose Aging impacts pulsatility of blood vessels in the brain, reflecting vascular health. Resolving characteristics of cardiac pulsatility requires faster acquisitions than traditional fMRI. An ultrafast fMRI method was developed and applied to sample several harmonics of cardiac pulsations at 7 T.
Charles Marchini, Dema Abdelkarim, Yuhui Chai, Monica Fabiani, Gabriele Gratton, Bradley P. Sutton   +5 more
wiley   +1 more source

Quantifying Cardiac, Respiratory, and Low Frequency Components of CSF Motion From fMRI Inflow Effects

Magnetic Resonance in Medicine, EarlyView.
ABSTRACT Purpose Cerebrospinal fluid (CSF) flow oscillations have emerged as a potentially important marker related to brain clearance, but their acquisition often relies on specialized imaging MRI sequences. The purpose of this work was to enable quantitative assessment of CSF flow associated with cardiac, respiratory, and low‐frequency cycles using ...
Pontus Söderström, Cecilia Björnfot, Britt M. Andersson, Jan Malm, Anders Eklund, Anders Wåhlin   +5 more
wiley   +1 more source

Investigating Stress During a Virtual Reality Game Through Fractal and Multifractal Analysis of Heart Rate Variability

Applied System Innovation
This article presents the process of creating a virtual reality (VR) game designed to assess the impact of stress on heart rate variability (HRV). The game features dynamic and challenging scenarios to induce stress responses, incorporating advanced 3D ...
Penio Lebamovski, Evgeniya Gospodinova
doaj   +1 more source

Statistical properties of detrended fluctuation analysis

Journal of Statistical Computation and Simulation, 2009
The main goal of this work is to consider the detrended fluctuation analysis (DFA), proposed by Peng et al. [Mosaic organization of DNA nucleotides, Phys. Rev. E. 49(5) (1994), 1685–1689]. This is a well-known method for analysing the long-range dependence in non-stationary time series.
Crato, Nuno, Linhares, R.R., Lopes, Sílvia R. C.   +2 more
openaire   +2 more sources

Using a social‐ecological macrosystems framework to understand how human activities alter ecological synchrony

People and Nature, EarlyView.
Abstract Different aspects of ecological systems, biotic or abiotic, often fluctuate in coordinated patterns over space and time. Such high concordance between ecological processes is often referred to as ecological synchrony. Human activities, including and beyond climate change, have the potential to alter ecological synchrony by disrupting or ...
Yiluan Song, Mallory Barnes, K. Ann Bybee‐Finley, Kyla M. Dahlin, Travis McDevitt‐Galles, Stephan B. Munch, Guillermo E. Ponce‐Campos, Casey Youngflesh, Benjamin Zuckerberg, Kai Zhu   +9 more
wiley   +1 more source

An opportunity index to anticipate when subseasonal predictions are useful

Quarterly Journal of the Royal Meteorological Society, EarlyView.
Simultaneously active subseasonal windows of forecast opportunity can be combined into a single opportunity index, which can be used operationally to anticipate enhanced or reduced subseasonal prediction skill. For predictions of temperature anomalies in Switzerland during summer—a region and season with particularly low predictability—skill can nearly
Dominik Büeler, Maria Pyrina, Adel Imamovic, Christoph Spirig, Daniela I. V. Domeisen   +4 more
wiley   +1 more source