Academic Articles & Research Papers

Methodological Background for Spectral Analysis, Illustrated by Studying the Number of Ukrainian Population

A data series usually has three components: trend, periodic (seasonal or cyclic) and random. Cyclic recurrence is periodic swings going beyond the limits of one year. The time span between the two next peaks within one year is considered as...

Spectral analysis in geophysics

Intra-seasonal Variation of Rainfall and Climate Characteristics in Kabul River Basin

In Afghanistan, spring and summertime flash floods result in 54.3% of all natural disasters with an average annual economic loss of US$92.17 million between 1990 and 2014. Knowledge of climate and rainfall periodicity are urgently needed fo...

Numerical Modal Analysis of Vibrations in a Three-Phase Linear Switched Reluctance Actuator

This paper addresses the problem of vibrations produced by switched reluctance actuators, focusing on the linear configuration of this type of machines, aiming at its characterization regarding the structural vibrations. The complexity of t...

Tracking Hydrological Regime Shifts Through the Anthropocene: The Samara River, Southern Cis-Urals

The Samara River is a left-bank tributary of the Volga with a total basin area of 46,500 km2, of which 22,800 km2 is the gauged area analyzed in this study. This river system serves as a case study for examining hydrological transformations...

Is There a Retrograde Accretion Disk around 4U 1626–67? Tracking Torque Reversals with a State-space Model

X-ray timing studies of the persistent, Galactic, accretion-powered pulsar 4U 1626−67 reveal torque reversals, during which the pulse frequency ν ( t ) alternates between multiyear episodes of secular acceleration and deceleration, separate...

Enhancing Communication Security in Drones Using QRNG in Frequency Hopping Spread Spectrum

This paper presents a novel approach to enhancing the security and reliability of drone communications through the integration of Quantum Random Number Generators (QRNG) in Frequency Hopping Spread Spectrum (FHSS) systems. We propose a mult...