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The main cause of errors in the navigation of the Global Positioning System (GPS) satellite is the ionospheric delay. Therefore, ionospheric delay forecasting studies play an important role in the reduction of the positioning error. This paper focuses on forecasting of ionospheric delay using the statistical Holt-Winter method during the quiet and disturbed days in October 2011, using GPS Ionospheric...
In this paper, a new personal safety forewarning approach (PSFA) using GPS positioning and spatial analysis is presented. Specifically, we discussed the spatial topological relationships between the spatiotemporal objects related to personal safety. On that base, safety state is assessed through the calculation of a state matrix and then how to affirm the factors related to forewarning response is...
Aiming at the problem of how to make use of the atomic clocks offered by Micro-PNT to make Global Navigation Satellite System (GNSS) receivers fulfill fast positioning with the recovery of the satellite navigation signal, this paper discusses the fast positioning method which omits the step of frame synchronization and proposes a constellation-triangle selecting algorithm based on high-precision clock...
In this paper, a Binary Robust Invariant Scalable Keypoints (BRISK) based detection is utilized to facilitate the flying unmanned aerial vehicle (UAV) localization within its autonomous landing on the runway. Specifically, two target detection algorithms are proposed and developed as the BRISK-supported approach. Dataset of images and differential GPS are recorded by a ground stereo vision guidance...
Forest height estimation is very important in order to estimate biomass or volume of the tree. Various method and technique can be used to estimate the height. However, the accuracy is a main challenge to meet the requirement. Interferometry Synthetic Aperture Radar (IFSAR) Intermap X-band is one of the technology that have potential in estimating tree height. It is an active remote sensing that penetrates...
The current traditional system of paper documents adopted by Fire Department had lead to the inability of the fire fighters to locate usable and functioning hydrants in an efficient and effective manner which can jeopardize any rescue mission. Hence, there is a need to revised the Fire Department current system and develop a new system that is much more easier, portable and also time and cost effective...
This study is aimed at evaluating the trade-off between Global Positioning System (GPS) accuracy and power saving from reduction of number of channels. The study is conducted for number of GPS receiver channels of 4 to 12 for two scenarios: 1) Normal scenario with full range of available GPS satellites; 2) Obstruction scenario with GPS satellite elevation cutoff of 20°. It is observed that increase...
The location of a mobile user is used to deliver context sensitive information like advertisements and deals. Predicting the future possible locations of a mobile user can help target specific services. Nokia provided researchers with data collected from around 200 mobile users over a period of about 2 years for the purpose of research. Previous efforts have attempted either to predict the location...
Most of the landslide and flood prediction models require the Digital elevation Model (DEM) as the input. DEM is the digital representation of topographic and manmade features located on the surface of the earth. DEM also needed in hydrologic analyses, resource management and environmental assessment and including interferometry synthetic aperture radar (InSAR) applications. The increased use of DEM...
Attendance system which is currently excist still has weaknesses. The first is the long queues in front of the attendace machine at the time to come to work and leave work. The second is cheating, employees can ask her/his friend to do attendance process. The third is mostly attendance system has not been connected with the payment system in human resouces software or in the finance department. The...
Despite several studies using the multiple-aperture interferometry (MAI) technique, X-band SAR has rarely been applied to MAI-based studies due to their shorter decorrelation timescale. However, the relatively short antenna length and high temporal resolution of the COSMO-SkyMed X-band SAR system provides an opportunity to measure the precise displacement in the along-track direction. In this study,...
The accuracy of COSMO-SkyMed DEMs is investigated using StripMap mode images, acquired during the interferometric Tandem-Like mission characterized by a temporal baseline of 24 hours and spatial baselines maintained around 150–200 m. Some Couples of both Ascending and Descending interferometric pairs, acquired on selected test sites located in the California have been processed using the open source...
For the quality analysis of WorldDEMTM database a global validation campaign was established. The goal is to validate the global quality of the WorldDEMTM dataset. For this, different areas on different continents are under evaluation. To get a complete picture, different landscapes were evaluated with different reference data. For reference, GPS points, ICESat data and Lidar reference DEMs were used...
SPOT and Pléiades images acquired since 2002 are used to describe velocity and elevation changes on Astrolabe Glacier, East Antarctica. Multi-temporal pairs of images are used to generate velocity fields by automatically tracking surfaces features. Stereo-pairs are used to create DEMs. Using three DEMs (2003, 2007 and 2013), we describe a surprising surface elevation increase since 2002, that reached...
This paper analyzes the theoretical accuracy limitation of synchrophasors measurements on phase angle and frequency of the power grid. Factors that cause the measurement error are analyzed, including error sources in the instruments and in the power grid signal. Different scenarios of these factors are evaluated according to the normal operation status of power grid measurement. Based on the evaluation...
In the field of precision agriculture (PA), Un-manned Aerial Vehicles (UAVs) are creating new opportunities for remotely assessing various characteristics of crops. In this paper, we present two main contributions that were evaluated on a novel application: mapping red clover ground cover (RCGC). First, we develop an integrated system for collecting, pre-processing and analyzing aerial data for the...
As unmanned aerial systems (UASs) become ever more ubiquitous with National Airspace (NAS) commercial and civilian operations, test sites and proving grounds need to be developed and heavily researched. Small UASs are being used as remote sensing systems, on demand, at the personal level, thus “personal remote sensing” scientific data drones urgently need Ground Truthing Test Sites beyond compliance...
This paper presents an algorithm for cooperative UAV navigation that exploits vision-based sensing, standalone GPS, differential GPS among antennas embarked on different flying platforms, and measurements obtained by inertial sensors and magnetometers. Unlike other cooperative navigation approaches, the developed technique is mainly aimed at improving navigation performance in outdoor environments,...
Tracking accuracy plays a critical role in V2V (vehicle-to-vehicle communications) based active safety applications. This paper proposed a beacon rate control algorithm to reduce the tracking error. By analyzing the vehicle trajectory tracking process, it is found that the tracking error is proportional to the moving status of a vehicle, as well as the data delay. Due to the constraint of the wireless...
Real Time Kinematic (RTK) Global Positioning System (GPS) uses carrier phase measurement from GPS signal and it has a high accuracy but has integer ambiguity resolution problem which causes cycle slips and requires good satellite visibility as well. RTK was originally developed for applications such as surveying; in our case the target application is the tracking and the control of a robot hexacopter...
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