Results 61 to 70 of about 273,564 (272)

Application of Fast Fourier Transform to Ozone Data at Lagos, Nigeria [PDF]

open access: yes, 2008
Fast Fourier Transform (FFT) is a mathematical too l often used to represent tim e-varying real data set function /(1). In this paper, the FFT was applied to the measured stratospheric ozone data at Lagos from 1997 to 2002.
Akinyemi, M. L.
core  

Enhancement of Fingerprint Using FFT×|FFT|n Filter

open access: yesProcedia Computer Science, 2015
AbstractFingerprint enhancement is an indispensable task in the Automatic Fingerprint Identification System. In this paper, a simple method for the enhancement of fingerprint images is presented, which is based on FFT. The FFT is found out after the fingerprint image is partitioned into blocks.
Neethu, S.   +2 more
openaire   +1 more source

Miniature Nanomesh Mechano‐Acoustic Sensor with Wide Linear Dynamic Range, Broad Bandwidth, and Flat Frequency Response

open access: yesAdvanced Functional Materials, EarlyView.
A miniaturized mechano‐acoustic sensor is developed using an electrospun PVDF nanomesh as the diaphragm in a capacitive sensor structure. Unlike conventional nanomesh‐based sensors, it achieves high linear sensitivity, a broad and flat frequency response, and a compact form factor.
Jeng‐Hun Lee   +8 more
wiley   +1 more source

Simulation of interaction of antennas in the near zone

open access: yesВісник Харківського національногоуніверситету імені В.Н. Каразіна. Серія: Радіофізика та електроніка
Relevance. Obtaining the minimization or maximization of the interaction between the radiating and receiving antennas (or the receiving antenna with fields reflected from some obstacle) due to the orientation and location of the antennas at a certain ...
М. Legenkiy, V. Khrychov
doaj   +1 more source

Harmonizing the Pyrene and Ether Groups in Covalent Triazine Polymers for Highly Effective H2O2 Photosynthesis via One‐Step Two‐Electron Oxygen Reduction

open access: yesAdvanced Functional Materials, EarlyView.
The pyrene and ether groups are incorporated into the covalent triazine polymer (CTP) structure. The synergistic effect of the two functional groups endows CTP with better electron transfer, light absorption, and oxygen activation properties. An impressive apparent quantum yield (13.2% @420 nm) and a remarkable solar‐to‐chemical conversion efficiency ...
Chong Wang   +10 more
wiley   +1 more source

Power spectral analysis of occipital area during eyes-closed and eyes-open

open access: yesLiberabit
Background: Power spectral analysis of the occipital cortex is essential for characterizing brain activity during attentional and relaxed states. Objectives: This study aims to develop a predictive model capable of distinguishing between eyes-closed (EC)
Adolfo González-González   +3 more
doaj   +1 more source

Efficient SAR Raw Data Compression in Frequency Domain [PDF]

open access: yes, 1999
SAR raw data compression is necessary to reduce huge amounts of SAR data for a memory on board a satellite, space shuttle or aircraft and for later downlink to a ground station.
Benz, U.C., Fischer, J.V., Moreira, A.
core  

In Situ Study of Resistive Switching in a Nitride‐Based Memristive Device

open access: yesAdvanced Functional Materials, EarlyView.
In situ TEM biasing experiment demonstrates the volatile I‐V characteristic of MIM lamella device. In situ STEM‐EELS Ti L2/L3 ratio maps provide direct evidence of the oxygen vacancies migrations under positive/negative electrical bias, which is critical for revealing the RS mechanism for the MIM lamella device.
Di Zhang   +19 more
wiley   +1 more source

Improved anomaly diagnosis of production facilities by combining Autoencoder with spectral characteristics

open access: yesNihon Kikai Gakkai ronbunshu
In a previous study, we had proposed a method for detecting abnormalities using an Autoencoder. It considers the amplitude value of each frequency spectrum while performing the FFT analysis of time-series data.
Fuki SAKA   +5 more
doaj   +1 more source

Cryogenic Focused Ion Beam Milling to Investigate the Anisotropic Magnetotransport Properties of Bismuth Microcrystals

open access: yesAdvanced Functional Materials, EarlyView.
The highly anisotropic Fermi surface of bismuth results in variations in magnetotransport properties across different crystallographic directions, which can be characterized by studying microcrystals. To avoid the observed surface melting under room temperature Focused Ion Beam (FIB) irradiation, two low‐temperature FIB fabrication methods are proposed
Amaia Sáenz‐Hernández   +6 more
wiley   +1 more source

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