Kutubuddin Ansari

IntGeo Solution Pvt. Ltd., New Delhi, India

The study investigated precipitable water vapour (PWV) variation over Northeast Japan by using more than two decades (2000 to 2022) of measurements. These data have been extracted from 36 Global Navigation Satellite System (GNSS) networks and interpolated with thin‐plate spline interpolation to understand its spatial variation over the region. PWV...

This study provides critical insights into hydrodynamic and measurement techniques in the NW Banda Sea, enhancing our understanding of oceanic processes. It focuses on the physical oceanography conditions in Eastern Indonesia, demonstrating the connection between a 2D hydrodynamic model simulation and oceanographic phenomena, including surface curr...

The earthquake Mw 7.6 occurred on January 15, 2023, in the Tanimbar region, the southeastern part of Molucca, Indonesia, and generated a wide ground shaking around IV-VI MMI following several damages and early warning of the tsunami. The hypocenter was located deeper than the common slab contour, which may direct another blind tectonic system calle...

The Indian western coast is petroliferous, and therefore draws attention from both academicians and industrial experts. In this work, geomorphic indices have been calculated to decode neotectonics of the Konkan onshore region at the India’s west coast. Earthquake and Bouguer anomaly data have been used along with the present-day stress data from th...

Morphometric studies coupled with geophysical investigations from petroliferous basins provide valuable information about tectonics of the regions. We deduce six morphologic parameters from the River Cauvery's designated (sub)watersheds and perform dendrogram clustering analysis. The main channels of the (sub)watersheds showcase steeper gradient an...

This chapter is a review of crustal deformation studies by using Global Navigation Satellite System (GNSS) measurements in western India. GNSS velocity field in India-fixed Reference Frame (IREF) are reviewed and modelled by using well known technique known as Singular Spectrum Analysis (SSA). The change in GNSS velocity field points out a consider...

Modern geodesy can monitor the geodynamic motion of the Earth because of tectonic activities and modifications in the environment because of sea level variation and atmospheric changes. The Tohoku‐Oki earthquake (Mw 9.1) occurred on 11 March 2011 in Japan and was the strongest devasting earthquake in modern world history. This article discussed the...

The study investigates tectonic movements in northeast Japan by using long-term (2000-2022) global navigation satellite system (GNSS) and tide gauge measurements. The effect of the 2011 Tohoku-Oki earthquake including the other eight seismic events that occurred within this period is also discussed using GNSS time-series. The result showed the brea...

Morphometric studies coupled with geophysical investigations from petroliferous basins provide valuable information about tectonics of the regions. We deduce six morphologic parameters from the River Cauvery's designated (sub)watersheds and perform dendrogram clustering analysis. The main channels of the (sub)watersheds showcase steeper gradient an...

The study investigates sea-level measurements along the coastal area of Europe for the 60-year (1961–2020) time span. Linear and quadratic modeling of tide gauge measurements showed an almost positive rate of trend of sea-level rise (0.09 to 3.6 mm/yr) and low acceleration (−0.05 to 0.40 mm/yr²). A least-squares harmonic estimation tidal modeling w...

The article “Ionospheric scintillation characteristics over Indian region from latitudinally-aligned geodetic GPS observations” was originally published Online First without open access. After publication in volume 16, issue 3, page 2675–2691, the author decided to opt for Open Choice and to make the article an open access publication.

The study investigates ionospheric total electron content (TEC) variation over Turkey from the five selected global navigation satellite system (GNSS) stations situated in diverse parts of Turkey. The geomagnetic indices are used and observed TEC are modeled with the technique known as Empirical orthogonal function (EOF). It is valuable to note tha...

Geomorphological and geophysical studies from western Rajasthan basins- Barmer, Jaisalmer & Bikaner-Nagaur

The lowest part of the atmosphere known as the troposphere extends from the surface of the Earth to an approximate altitude of 10 km. This atmospheric densest layer covers almost all water vapor, precipitation, and cloud. The study investigated precipitable water vapor (PWV) variation over Northeast Japan by using more than two decades (2000 to 202...

The dynamic geological features of the Pieniny Klippen Belt (PKB) in southern Poland are nowadays a focal point of researchers as it is recognised as an active zone of crustal discontinuity. In the present study, we employed long-term analysis of ground-based global navigation satellite system (GNSS) measurements (from 2004 to 2020) to probe the cr...

The complexity of the active tectonic system in East Indonesia has influenced various types of seismicity in the Seram Sea, resulting in several significant earthquakes. In the last decade, there were two devastating earthquakes, Mw 6.2 (October 31, 2017) occurred with the thrust mechanism as typical of active subduction while Mw 6.5 (September 26...

The study investigates sea-level measurements along the coastal area of Europe for the sixty-year (1961-2020) time-span. Linear and quadratic modeling of tide-gauge measurements showed an almost positive rate of trend of sea-level rise (0.09 to 3.6 mm yr-1) and low acceleration (-0.05 to 0.40 mm yr-2). A Fourier transform tidal modeling is carried...

Indian regional navigation satellite system (IRNSS) is a regional navigation system established by the Indian government. The growth of IRNSS is fully operational and provides a high impact on the international political as well as economic sectors. The study reviewed such a kind of growth briefly and highlighted the IRNSS economy in the global mar...

Forecasting ionospheric total electron content (TEC) has been of great interest among ionospheric researchers and radio propagation scientists as it critically affects the operation of dynamic technological systems relying on space-based radio propagation. In this context, this article attempts to forecast ionospheric TEC using a bi-long short-term...

The Gulf of Mannar has been producing natural gas in the Sri Lankan portion. This indicates that a detail geoscientific study is to be undertaken from the Indian section of the gulf, which can have a far-reaching implication in the Indian petroleum geoscience. In this work, morphometric and gravity studies were made from the gulf/basin near the ons...

The Svalbard archipelago region is a group of islands in the Arctic Ocean, located between the North Pole and the northern coastal region of Norway at high latitudes. The current study focuses on the spatiotemporal distribution of total electron content (TEC) over the Svalbard archipelago region with the ground-based global positioning system (GPS)...

Ionospheric scintillations pose one of the biggest threats to Satellite-Earth communication links in the communication and navigation systems services whose occurrence characteristics could be explained through the strength of fading (amplitude scintillation index; S4) and the rapidity of the fades (decorrelation time; 𝜏0). In the present work, we...

The Flores earthquake (Mw 7.3) occurred on December 14, 2021, in the Flores Sea and was responsible for an unknown active fault known as the Kalatoa fault. The earthquake's epicenter was located around 100 km north of Flores Island, Indonesia. We analyzed the different earthquake mechanisms using moment tensor (MT) inversion for the mainshock and t...

Morphometry and active tectonics of the Konkan coast, western India The Indian western coast is petroliferous, and therefore draws attention from both academicians and industrial experts. In this work, geomorphic indices have been calculated to decode neotectonics of the Konkan onshore region at the India’s west coast. Recent earthquake and Bougue...

The determination of soil moisture (SM) that directly affects agriculture productivity and brings uncertainty in climate change is crucial in Nepal because it's being an agricultural country. The main purpose of this study is to estimate the soil moisture index (SMI) of Nepal from 2012 to 2020 and predict the SMI for 2021. The relationship between...

Ionospheric irregularities remain as a challenging concern among space scientists and engineers as it can pose severe threats to satellite-based services by introducing amplitude and phase scintillations in the transionospheric radio signals. The scintillations may cause degradation of the positioning, navigation, and timing (PNT) services or even...

The real shape of the earth is approximated closer to an ellipsoidal curvature other than a homogeneous half-space. Therefore, the use of the dislocation theory of homogeneous half-space for the farthest epicentral distance brings an error. The study investigates the far-filed effect of dislocation modeling of homogeneous half-space due to the elli...

The study investigates a relative analysis of two regional navigation satellite systems namely the Indian regional navigation satellite system (IRNSS) and the Quasi-zenith satellite system (QZSS) working in the Asia–Pacific region. It was expected that the combined precise point positioning (PPP) will attain a highly stable and accurate positioning...

Water levels in many existing ponds and shallow tube wells are found lowering day by day in the Bhabar and Terai regions of Nepal. For the sustainable management of the groundwater, development of artificial recharge ponds is considered the best approach in this region. The suitable site selection for the artificial recharge ponds requires surface...

In the current study, we investigated the total electron content (TEC) variations over Thailand region by using five multi-constellation Global Navigation satellite system (GNSS) signals. The STEC variations for all multiple GNSSs were computed with well-known ionospheric Klobuchar model and compared with the STEC values of Global Ionospheric map (...

The ionospheric error is the largest error source of positioning, especially when electron density becomes high during geomagnetic storms. Real-time kinematic (RTK) positioning during the storm time often has higher fluctuation and noise errors in positioning. Therefore, in this work, a technique based on Kalman filter with implementation of singul...

The tide gauge measurements from Global Navigation Satellite System reflectometry (GNSS-R) observables are considered to be a promising alternative to the traditional tide gauges in the present days. In the present paper, we deliver a comparative analysis of tide-gauge (TG) measurements retrieved by Quasi-Zenith Satellite System-Reflectometry (QZSS...

The study presents linear and nonlinear (smoothing spline) modeling of sea-level measurements on the basis of a 50-year (1971-2020 A.D.) permanent service for mean sea-level (PSMSL) tide gauge data at the coastal area of the Gulf of Thailand. These tide gauge measurements are compared with the ORAS5 data extracted from the latest ECMWF atmospheric...

The coast is a unique environment where land, sea, and atmosphere interact and interplay continuously influencing a strip of spatial zone defined as a coastal zone. In other words, coastal zones are the areas having the influence of both marine and terrestrial processes. The aim of this study is to present a review of the Global Navigation Satellit...

The Lombok island is a part of the Sunda Arc, tectonically controlled by the subduction system of the Indo-Australian Plate in the southern part while the Flores thrust in the northern part. A sequence of major earthquakes consisting of Mw 5.9-6.9 struck in July-August 2018 and generated massive loss and damage in the Lombok and neighboring regions...

The rise of mobility, such as Urban Air Mobility (UAM) and autonomous driving, as well as robotics technology in the agricultural industries, has created a demand for high-precision GNSS positioning. In these cases, error correction using Observation Space Representation (OSR) or State Space Representation (SSR) is essential for high-precision navi...

The study established a theoretical relation between weighted position dilution of precision (WPDOP) and standard deviation (STD) of positioning error (ϵ/σ <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">R</sub> ) derived by linear Kalman filter (KF). The obtained results exposed a rectangular hyperbol...

The study investigates sea-level measurements observed from 12 tide gauge sites over the Indian coastal area during the last two decades. Initially, the rise of sea-level (slope) and acceleration is estimated by fitting the linear and parabolic equations in the recorded data from tide gauge measurements. The estimated results show the abrupt change...

The Indian plate on the western side has a 'divergent' boundary with the African plate named Central Indian Ridge (CIR), and a 'transform' boundary with the Arabian plate called the Owen Fracture Zone (OFZ). On the northern side, the Indian plate converges with the Eurasian Plate and forms the Himalayas, also known as Main Himalayan Thrust (MHT). T...

The aim of the current study is to apply multivariate singular spectrum analysis (M-SSA) techniques and investigate both shallow and intermediate depth earthquake characteristics in eastern Nepal and the southern Tibetan Himalaya. Space-time-depth-magnitude (STDM) domain time-series were computed for a time window of 776 events, using a complete ca...

This paper compares the positioning accuracy obtained from the GIM VTEC, the Klobuchar model, and the IRI-2016 model at Chiang Mai and DPT9 stations, Thailand, during an intense geomagnetic storm of 2021 (on May 12, 2021). The results show that the diurnal variation of the Klobuchar modeled VTECs show the same trend as that of the observed GIM VTEC...

This paper proposes initially to apply convolutional neural network (CNN) for detecting the equatorial plasma bubbles on the ASI images. The considered CNN model is the YOLO v3 tiny model under a deep learning API (Keras), running on top of the machine learning platform (TensorFlow). Our program for EPB detection is written in Python that is extend...

The study investigates the real-time sea-level measurement from six tide gauge stations at the coastal area of Japan during the period 2017 to 2019. Initially, the six co-located global navigation satellite station (GNSS) sites vertical velocity has been observed followed by estimation of the relative tide gauge velocities. The results showed that...

Thailand is the country situated at the center of the Indochinese Peninsula counted among ten countries of the world where it is likely to encounter the climate changes and extreme weather events. The ionosphere, that plays an important role in the space weather condition, make the country perfect for the ionospheric study. Therefore, in the curren...

Landslides are one of the most recurrent natural hazards occurring each year in the hilly and mountainous regions of Nepal causing massive loss of life and property. Natural hazards such as landslides cannot be avoided completely but the processes and consequences can be mitigated. The main objective of the study was on the application of Geographi...

The most powerful Tohoku-Oki (TO) earthquake that occurred in Japan on 11 March 2011 affected Japan and affected South Korea as well. In the current study, we investigated contemporary geodetic deformation inside South Korea before and after the TO earthquake using Global Navigation Satellite System (GNSS) measurements from 01 January 2008 to 31 De...

River channel migration involves the lateral migration of an alluvial river channel across its floodplain which is mainly driven either by bank erosion or point bar deposition over time. It is the study of major rivers of Tulipa Sub-Metropolitan City using remote sensing images over the span of 11 years (2010-2020). The river channel migration d...

The study examined the ionospheric total electron content (TEC) variation based on global navigation satellites system (GNSS) stations located inside the Arabian Peninsula. An interpolation technique known as cubic spline is used and numerical investigation of TEC variation has been done from 2015-2017. First, global ionospheric map (GIM) data is i...

This study investigates the multipath error modelling and mitigation for triple-frequency global navigation satellite system (GNSS) signals inside South Korea. Multi-frequency global positioning system (GPS), globalnaya navigatsionnaya sputnikovaya sistema (GLONASS), and Galileo data are collected in an environment where the receiver must track the...

We studied BeiDou and QZSS signals by taking 10 MGEX network sites over Asia-Pacific region. Comparative investigation with the number of satellite visibilities (NSV), signal-to-noise ratio (SNR) and multi-path combination (MPC) of diverse constellations are carefully examined to evaluate the individual performance. The SNR data was extracted on a...

We studied five multi-constellation systems (GPS, GLONASS, Galileo, BeiDou, and QZSS) signals by selecting 10 MGEX network stations over the Asia-Pacific region. A comparative analysis with the number of satellite visibilities (NSV), signal-to-noise ratio (SNR), multi-path combination (MPC), precise point positioning (PPP) including the phase and...

This article reviews geometric model parameters (length, width, depth, dip angle, and strike) of the Main Himalayan Thrust (MHT) in Eastern, Western, Central, and other portions of the Himalaya. It is expected that when a fieldworker works on the Main Frontal Thrust (MFT), these compiled data will be useful in generating models involving subsurface...

Global positioning system-Interferometric Reflectometry (GPS-IR) method is applied to measure the sea level measurement by utilizing the geodetic quality of GPS receiver for detecting the adjacent ecosystem, including the advantages of climate-related or non-related sea level information. The comparative analysis of tide gauge (TG) measurement inte...

This analysis is an extension of the studies based on the space-time-magnitude (STM) domain nearest-neighborhood distances (ƞ) obtained from two successive earthquakes. We included epicentral depth as a parameter, and established a new analytical solution for seismicity clustering in the space-time-depth-magnitude (STDM) domain. The proposed techni...

This analysis investigates the spatiotemporal variation of total cloud cover (TCC) across South Korea from 96 visual observation stations (VOS) during the years 2010–2019. The thin‐plate spline interpolation technique is used to interpolate the spatial variation of TCC within the country. The annual average of TCC distribution is closely related to...

In this paper, we investigate the variation of ionospheric total electron content (TEC) derived from global positioning system (GPS) observations at a low latitude station in Magna (Station code: RASH, Geographic coordinate: 28°17’N, 34°47’E), Saudi Arab. The study includes a linear regression method for validating the relationship between regional...

This analysis uses 3 years hourly observations of total electron content (TEC) from 5 global positioning system (GPS) station across Nepal to analyze the spatial trend. For this purpose, empirical orthogonal function modeling is used to investigate the annual and monthly variation inside the country. Empirical orthogonal function base functions and...

The ionospheric scintillation is a rapid phase and amplitude fluctuation of satellite signals due to the small-scale irregularity of electron density in the ionosphere. The characterization of the scintillation index in a proper way is a crucial aspect of the Global Positioning System (GPS) satellite signals for the purpose of space-based navigati...

Global positioning system (GPS) stations located along coastal areas have the ability to measure tide gauge records by reflected signal reception from the sea water surface. In this study we used the GPS signal-to-noise ratio data from the GPS station (44. 6257 ⁰N, 124.0455 ⁰W) located at South Beach, Oregon, United States, to estimate the tide gau...

Real-Time Positioning (RTP) is a technique used to locate the static or moving objects with an error as small as possible. Although significant work has been conducted, and several kinds of methodologies are planned on high-precision positioning and surveying applications, however, there is substantial scope for new techniques which would afford a...

South Korea forms the Korean Peninsula and is considered to be tectonically more stable than the other regions of Eastern Asia. Global Navigation Satellite System (GNSS) sites installed in the country contribute to geoscientific studies on contemporary deformation, strain pattern and current kinematics of tectonic blocks. In the current study, we u...

Accurate modeling of ionospheric total electron content (TEC) is an important aspect for mitigating the threats of trans ionospheric delay error in satellite communication, earth observation, space-based navigation, timing applications as well as space weather forecasting services. In recent years, singular spectrum analysis (SSA) has been proved t...

The electronic structure, mechanical stability, phonon dispersion and vibrational characteristics of half-Heusler alloys, ScAuX (X = Si, Ge, Sn, Pb) have been analyzed in framework of Density Functional theory(DFT). The alloys are crystallize in face centered cubic having F4¯3m(#216) space group. First-principles simulation reveals that all the all...

The concept of friction damper is widespread technique and used to reduce the structural vibrations in many industrial applications. These friction dampers are generally coated with low wear rate materials to reduce the fretting wear. This paper investigates the use of physical vapor deposition (PVD) nitride based AlTiN coating material applied ove...

The ionospheric scintillation is a rapid phase and amplitude fluctuation of satellite signals due to the small-scale irregularity of electron density in the ionosphere. The characterization of the scintillation index in a proper way is a crucial aspect of the Global Positioning System (GPS) satellite signals for the purpose of space-based navigatio...

Global Positioning System (GPS) stations located along coastal areas have the ability to measure tide gauge (TG) records by reflected signal reception from the sea water surface. In this study we used the GPS signal-to-noise ratio (SNR) data from the SEPT station (44.63 ⁰N, 124.05 ⁰W) located at South Beach, Oregon, USA, to estimate the TG records...

In this study, we investigated the behavior of equatorial plasma bubble irregularities under different geomagnetic conditions during March 2015 and September 2017. It was used Total Electron Content (TEC) data obtained from SGOC (6,89 oN, 79,87 oE), IISC (12,94 oN, 77,57 oE) and HYDE (17,40 oN, 78,50 oE) receiver stations which located between the...

This analysis uses 3 years hourly observations of total electron content (TEC) from 5 global positioning system (GPS) station across Nepal to analyze the spatial trend. For this purpose, empirical orthogonal function modeling is used to investigate the annual and monthly variation inside the country. Empirical orthogonal function base functions and...

A significant amount of research has been conducted in Southwest (SW) Japan on climate modeling, disaster management, earthquake prediction, precise positioning, datum definition, and reference frames. However, there is substantial scope for numerical modeling and forecasting of ionospheric Total Electron Content (TEC) variations over the region, w...

Industrial site selection is a strategic decision that involves several criteria considerations for technical, economic, social, environmental, and political issues. These criteria are generally described by using a number of different indicators, expressed in quantitative and qualitative ways with some possible uncertainties. Decision making requ...

A significant amount of work has been conducted in the Japanese islands on high-precision positioning, surveying, natural disaster mitigation, reference frame, and datum definitions, however, there is substantial scope for the exploring the current seismotectonic activity of Japan, which would provide further awareness of disaster management. The s...

The present study computes B-W extension model (extended Bursa-Wolf model) coordinate transformation parameters from World Geodetic System 1984 (WGS-84) to the Everest datum namely Everest (1830) and Everest (1956) using records of coordinate measurements from Global Positioning System (GPS) observable across Nepal region. Synthetic or modeled coor...

This paper presents the ionospheric Total Electron Content (TEC) variations over the low-middle latitude South Korean region using dual frequency Global Navigation Satellite System (GNSS) observations from 14 permanent stations with the data spanning approximately eight years (January 2010 to December 2017). Although, significant work has been cond...

In this paper, we investigate the Global Positioning System (GPS) derived ionospheric Total Electron Content (TEC) response to different levels of geomagnetic storms over the Indian region during the solar cycle-24. The corresponding storm-time effectiveness of the Global Ionosphere Maps (GIMs), International Reference Ionosphere (IRI-2016), and it...

The present paper investigates GPS, GLONASS, and Beidou observables from the Multi-GNSS Experiment (MGEX) network of stations in the East Asia region. Precise Point Positioning (PPP) estimates, Dilution of Precision (DOP), Slant Total Electron Content (STEC), and Zenith Total Delay (ZTD), along with their prediction from the Singular Spectrum Analy...

High-precision GPS measurements from 2002 to 2017 in Nepal has been analyzed and modeled with Autoregressive Moving Average (ARMA) method. The measured velocities of the GPS sites in ITRF-2014 indicate ~6-12 mm/yr N-S convergence inside the Nepal between India and Tibet. This convergence occurs in the southern and western border of Nepal but it is...

The present paper investigates precipitable water vapor (PWV) variations over the lower middle latitude Turkish region from the International GNSS Services (IGS) and Turkish Permanent GNSS Network (TPGN) observations. The diurnal, seasonal, annual, and rainfall time behavior of PWV and their relative deviations are presented covering the period fro...

A B S T R A C T: Deformation in active convergent wedges like the Himalaya occurs over different time and space scales requiring integrated datasets for holistic insights into wedge-scale deformation. A new long-time series (1998–2009) of geodetic, static Global Positioning System (GPS) dataset suggests that active deformation in the Darjiling-Sik...

In this paper, we investigate the Ionospheric Total Electron Content (TEC) variations over Manama, Bahrain through Global Positioning System (GPS) observations from an International GPS Services (IGS) station (BHR3, 26.21ºN, 50.61ºE) during the period January 2016 to October 2017. The estimated vertical TEC (VTEC) from international reference ionos...