Search Results - "Daniel, Okoh"

A Neural Network-Based Method for Time Series Modeling of 3-D Atmospheric Refractivity Using Radio Occultation Measurements by Nzeagwu, Jonas Nnabuenyi, Urama, Johnson O., Chukwude, Augustine E., Okoh, Daniel I.

“…Satellite measurements of the atmosphere by remote sensing techniques are becoming the trend for atmospheric probing. The problem is that such measurements are…”
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Assessment of the NeQuick-2 and IRI-Plas 2017 models using global and long-term GNSS measurements by Okoh, Daniel, Onwuneme, Sylvester, Seemala, Gopi, Jin, Shuanggen, Rabiu, Babatunde, Nava, Bruno, Uwamahoro, Jean

“…The global ionospheric models NeQuick and IRI-Plas have been widely used. However, their uncertainties are not clear at global scale and long term. In this…”
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Tropospheric radio refractivity trends over vegetation regions in Nigeria by Onuorah, Loretta O., Agbo, Godwin A., Okoh, Daniel I., Yusuf, Najib, Ibeh, Gabriel F.

“…Refractivity is an important parameter in understanding radio wave propagation in the troposphere. We investigated both the monthly variations of refractivity…”
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A Neural Network‐Based Ionospheric Model Over Africa From Constellation Observing System for Meteorology, Ionosphere, and Climate and Ground Global Positioning System Observations by Okoh, Daniel, Seemala, Gopi, Rabiu, Babatunde, Habarulema, John Bosco, Jin, Shuanggen, Shiokawa, Kazuo, Otsuka, Yuichi, Aggarwal, Malini, Uwamahoro, Jean, Mungufeni, Patrick, Segun, Bolaji, Obafaye, Aderonke, Ellahony, Nada, Okonkwo, Chinelo, Tshisaphungo, Mpho, Shetti, Dadaso

“…The first regional total electron content (TEC) model over the entire African region (known as AfriTEC model) using empirical observations is developed and…”
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Signatures of Equatorial Plasma Bubbles and Ionospheric Scintillations from Magnetometer and GNSS Observations in the Indian Longitudes during the Space Weather Events of Early September 2017 by Vankadara, Ram Kumar, Panda, Sampad Kumar, Amory-Mazaudier, Christine, Fleury, Rolland, Devanaboyina, Venkata Ratnam, Pant, Tarun Kumar, Jamjareegulgarn, Punyawi, Haq, Mohd Anul, Okoh, Daniel, Seemala, Gopi Krishna

“…Scintillation due to ionospheric plasma irregularities remains a challenging task for the space science community as it can severely threaten the dynamic…”
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First Study on the Occurrence Frequency of Equatorial Plasma Bubbles over West Africa Using an All‐Sky Airglow Imager and GNSS Receivers by Okoh, Daniel, Rabiu, Babatunde, Shiokawa, Kazuo, Otsuka, Yuichi, Segun, Bolaji, Falayi, Elijah, Onwuneme, Sylvester, Kaka, Rafiat

“…This is the first paper that reports the occurrence frequency of equatorial plasma bubbles and their dependences of local time, season, and geomagnetic…”
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Diurnal and seasonal variations of the occurrence of ionospheric irregularities over Nigeria from GNSS data by Ikani, Ojochenemi, Okeke, Francisca Nneka, Okpala, Kingsley Chukwudi, Okoh, Daniel, Rabiu, Babatunde

“…We investigate the occurrence of ionospheric irregularities in Nigeria during 2014, using the Global Navigation Satellite System (GNSS) total electron content…”
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A median absolute deviation-neural network (MAD-NN) method for atmospheric temperature data cleaning by Owolabi, Oluwafisayo, Okoh, Daniel, Rabiu, Babatunde, Obafaye, Aderonke, Dauda, Kashim

“…Some of the biggest challenges in climate change arise from bad dataset. To address this issue, we have developed a novel method for cleaning coarse…”
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Analyzing high temporal-resolution of GNSS-based ionospheric VTEC over Nigeria by Faruna, Solomon O., Wijaya, Dudy D., Setyadji, Bambang, Meilano, Irwan, Utama, Aditya K., Okoh, Daniel

“…This study focuses on high-temporal-resolution Vertical Total Electron Content (VTEC) estimation over Nigeria, which is crucial for enhancing satellite-based…”
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Assessment of the performance of the TOPGNSS and ANN-MB antennas for ionospheric measurements using low-cost u-blox GNSS receivers by Daniel Okoh, Aderonke Obafaye, Oluwakemi Dare-Idowu, Babatunde Rabiu, Anton Kashcheyev, Claudio Cesaroni, John Bosco Habarulema, Bruno Nava

“…Low-cost GNSS receivers have recently been gaining reliability as good candidates for ionospheric studies. In line with these gains are genuine concerns about…”
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Thermospheric Neutral Wind Measurements and Investigations across the African Region—A Review by Okoh, Daniel, Bounhir, Aziza, Habarulema, John Bosco, Rabiu, Babatunde, Katamzi-Joseph, Zama, Ojo, Taiwo, Wu, Qian, Makela, Jonathan J.

“…This paper briefly reviews studies of thermospheric neutral wind dynamics over the African region. The literature includes a review of the observations of…”
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Irregularities in the African ionosphere associated with total electron content anomalies observed during high solar activity levels by Anoruo, Chukwuma Moses, Rabiu, Babatunde, Okoh, Daniel, Okeke, Francisca Nneka, Okpala, Kingsley Chukwudi

“…In this paper, we investigate anomalies in total electron content (TEC) from 7 stations of the Africa Geodetic Reference Frame (AFREF) during the initial and…”
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Complexity and Nonlinear Dependence of Ionospheric Electron Content and Doppler Frequency Shifts in Propagating HF Radio Signals within Equatorial Regions by Akerele, Aderonke, Rabiu, Babatunde, Ogunjo, Samuel, Okoh, Daniel, Kascheyev, Anton, Nava, Bruno, Bolaji, Olawale, Fuwape, Ibiyinka, Oyeyemi, Elijah, Olugbon, Busola, Akinpelu, Jacob, Ajani, Olumide

“…The abundance of ions within the ionosphere makes it an important region for both long range and satellite communication systems. However, characterizing the…”
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A regional GNSS-VTEC model over Nigeria using neural networks: A novel approach by Daniel Okoh, Oluwafisayo Owolabi, Christopher Ekechukwu, Olanike Folarin, Gila Arhiwo, Joseph Agbo, Segun Bolaji, Babatunde Rabiu

“…A neural network model of the Global Navigation Satellite System – vertical total electron content (GNSS-VTEC) over Nigeria is developed. A new approach that…”
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Relationship between geomagnetic storms and occurrence of ionospheric irregularities in the west sector of Africa during the peak of the 24th solar cycle by Ondede, George Ochieng, Rabiu, A. B., Okoh, Daniel, Baki, Paul, Olwendo, Joseph, Shiokawa, Kazuo, Otsuka, Yuichi

“…The study of ionospheric irregularities is important since many technological systems might be influenced by the ionosphere. In this work, we use data from the…”
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Latitudinal Dependence of Ionospheric Responses to Some Geomagnetic Storms during Low Solar Activity by Joshua, B. W., Adeniyi, J. O., Olawepo, A. O., Rabiu, Babatunde, Daniel, Okoh, Adebiyi, S. J., Adebesin, B. O., Ikubanni, S. O., Abdurahim, B.

“…The Latitudinal dependence in the response of the Ionospheric F 2-layer electron density ( NmF 2) and peak height ( hmF 2) to three geomagnetic storms of May…”
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On the Relationships Between Sunspot Number and Solar Radio Flux at 10.7 Centimeters by Okoh, Daniel, Okoro, Eucharia

“…Regression analysis and neural network training procedures are used to study the relationship between sunspot number (SSN) and solar flux at 10.7 cm (F10.7)…”
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Speed and accuracy investigations of neural network algorithms for ionospheric modelling at an equatorial region by Abubakar, Sani, Okoh, Daniel, Tijjani, Bello Idris, Said, Rabia Salihu

“…Neural networks are very efficient tools for modeling, including ionospheric modeling. The training algorithm is important for achieving the optimum…”
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A neural network-based method for modeling PM 2.5 measurements obtained from the surface particulate matter network by Onyeuwaoma, Nnaemeka, Okoh, Daniel, Okere, Bonaventure

“…Air pollution is a global problem; hence, many countries devoted lots of resources towards its study and possible eradication. The major parameter indicator…”
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Machine learning approach for prediction of ionospheric irregularities on ROTI index over the Northern anomaly crest in Egypt during solar cycle 24 by M. Salah, Hager, Babatunde, Rabiu, Okoh, Daniel, Youssef, M., Mahrous, Ayman

“…This paper reports the prediction results of the ionospheric irregularities represented by the ROTI index close to the equatorial ionization anomaly's Northern…”
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