scholarly journals Evaluation of the Stability of the Darbandikhan Dam after the 12 November 2017 Mw 7.3 Sarpol-e Zahab (Iran–Iraq Border) Earthquake

2018 ◽  
Vol 10 (9) ◽  
pp. 1426 ◽  
Author(s):  
Yasir Al-Husseinawi ◽  
Zhenhong Li ◽  
Peter Clarke ◽  
Stuart Edwards
Keyword(s):  
Global Positioning System ◽  
Large Earthquake ◽  
Large Magnitude ◽  
Sar Images ◽  
Seismic Displacement ◽  
Surface Displacements ◽  
Medium Resolution ◽  
Global Positioning ◽  
Before And After ◽  
The Stability

We used a global positioning system (GPS), levelling, and Sentinel-1 data to evaluate the stability of the Darbandikhan dam in northeast Iraq after the 2017 Mw 7.3 Sarpol-e Zahab earthquake. GPS and levelling datasets collected in March and November 2017 were used to compute the co-seismic surface displacements of the dam. Sentinel-1 synthetic aperture radar (SAR) images collected between October 2014 and March 2018 were employed to recover the displacement time series of the dam. The large-magnitude displacement gradient on the dam crest hindered the estimation of the co-seismic displacement using this medium-resolution SAR data. However, Sentinel-1 images are sufficient to examine the stability of the dam displacement before and after the earthquake. The results show that the dam was stable between October 2014 and November 2017, but after the earthquake, Sentinel-1 data shows a continuous subsidence of the dam crest between November 2017 and March 2018. To the best knowledge of the authors, this study is the first that utilises InSAR to investigate the behaviour of a dam after a large earthquake.

scholarly journals Characteristics of BeiDou-3 Experimental Satellite Clocks

2018 ◽  
Vol 10 (11) ◽  
pp. 1847 ◽  
Author(s):  
Yifei Lv ◽  
Tao Geng ◽  
Qile Zhao ◽  
Jingnan Liu
Keyword(s):  
Global Positioning System ◽  
Precise Orbit Determination ◽  
Frequency Standard ◽  
Step Method ◽  
Stability Performance ◽  
Global Positioning ◽  
Clock Prediction ◽  
Block Iif ◽  
The Stability ◽  
Gps Block Iif

The characteristics of the improved Atomic Frequency Standard (AFS) operated on the latest BeiDou-3 experimental satellites are analyzed from day-of-year (DOY) 254 to 281, of the year 2017, considering the following three aspects: stability, periodicity, and prediction precision. The two-step method of Precise Orbit Determination (POD) is used to obtain the precise clock offsets. We presented the stability of such new clocks and studied the influence of the uneven distribution of the ground stations on the stability performance of the clock. The results show that the orbit influence on the Medium Earth Orbit (MEO) clock offsets is the largest of three satellite types, especially from 3 × 10 3 s to 8.64 × 10 4 s. Considering this orbit influence, the analysis shows that the Passive Hydrogen Maser (PHM) clock carried on C32 is approximately 2.6 × 10 − 14 at an interval of 10 4 , and has the best stability for any averaging intervals among the BeiDou satellite clocks, which currently achieves a level comparable to that of the PHM clock of Galileo, and the rubidium (Rb) clocks of Global Positioning System (GPS) Block IIF. The stability of the improved Rb AFS on BeiDou-3 is also superior to that of BeiDou-2 from 3 × 10 2 s to 3 × 10 3 s, and comparable to that of Rb AFS on the Galileo. Moreover, the periodicity of the PHM clock and the improved Rb clock are presented. For the PHM clock, the amplitudes are obviously reduced, while the new Rb clocks did not show a visible improvement, which will need further analysis in the future. As expected, the precision of the short-term clock prediction is improved because of the better characteristics of AFS. The Root Mean Square (RMS) of 1-h clock prediction is less than 0.16 ns.

scholarly journals Sustainability of Public Transportation: An Examination of User Behavior to Real-Time GPS Tracking Application

2020 ◽  
Vol 12 (22) ◽  
pp. 9541 ◽  
Author(s):  
Wei Chiang Chan ◽  
Wan Hashim Wan Ibrahim ◽  
May Chiun Lo ◽  
Mohamad Kadim Suaidi ◽  
Shiaw Tong Ha
Keyword(s):  
Real Time ◽  
Global Positioning System ◽  
Public Transport ◽  
Public Transportation ◽  
User Behavior ◽  
Mobile App ◽  
Gps Tracking ◽  
Inaccurate Information ◽  
Global Positioning ◽  
Before And After

Public transportation is an effective method of mobility that promotes cost-saving and is environmentally friendly. Poor public transport ridership in Malaysia is due to the unsatisfactory attitude of public transport users and inaccurate information on departure and arrivals. Sarawak, a state of Malaysia, is especially poor in ridership of public transport. A real-time Global Positioning System (GPS) tracking application (app) was found to be an effective tool to increase the ridership of public transport. Hence, a mobile app named UniBus was developed to enhance the ridership of public transport in Sarawak. The determinants that affect satisfaction and customer loyalty such as accessibility, reliability, comfort, safety, and security were all examined before and after the use of real-time GPS tracking app. The data was collected in Kuching, and targeted public transport users who used the UniBus app. The result indicated that all the mentioned variables were improved after using a real-time GPS tracking app. It is suggested that future studies can consider other factors such as service quality, availability, and perceived value as well as cover other states of Malaysia.

scholarly journals GPS based surface displacements – a proxy for discharge and sediment transport from the Greenland Ice Sheet

2014 ◽  
Vol 8 (4) ◽  
pp. 3829-3850 ◽  
Author(s):  
B. Hasholt ◽  
S. A. Khan ◽  
A. B. Mikkelsen
Keyword(s):  
Sediment Transport ◽  
Global Positioning System ◽  
Ice Sheet ◽  
Greenland Ice Sheet ◽  
Winter Precipitation ◽  
Annual Runoff ◽  
Surface Displacements ◽  
Global Positioning ◽  
Loss Of Mass ◽  
Gps Observations

Abstract. The elastic respond of the Earth's surface to mass changes has been measured with Global Positioning System (GPS). Mass loss as accumulated runoff and sediment transport from a 10 000 km2 segment of the Greenland Ice Sheet (GrIS) correlated very well (R2 = 0.83) with GPS measured uplift. Accumulated winter precipitation correlated fairly well with surface depression (R2 = 0.69). The relationships are based on seven years of runoff and sediment transport observations from the Watson River (2007–2013), winter precipitation from Kangerlussuaq Airport and GPS observations at Kellyville. GPS recordings of surface subsidence and uplift from 1996–2013 are used to calculate 18 years time series of annual runoff, sediment and solute transport and winter precipitation. Runoff and related transport of sediment and solutes increase over the period, while winter precipitation (land depression) tends to decrease. Based on the entire GPS record (1996–2013), it is shown that until 2005–2006 the mass balance of this segment of the GrIS was rather stable – since then there has been an increasing loss of mass, culminating in 2012.

Application of Information Technologies to Fuel Savings in Construction

2015 ◽  
Vol 803 ◽  
pp. 89-96
Author(s):  
Terezie Vondrackova ◽  
Martin Sip ◽  
Zdenek Caha
Keyword(s):  
Fuel Consumption ◽  
Global Positioning System ◽  
Information Technologies ◽  
Human Factor ◽  
Positioning System ◽  
Construction Company ◽  
Fuel Savings ◽  
Global Positioning ◽  
Before And After ◽  
Earthmoving Machines

This contribution deals with the benefits of the global positioning system, with the influence of the human factor on fuel consumption and with monitoring of further savings in operation of earthmoving machines in a construction company. Fuel consumption data of a selected earthmoving machine before and after installation of a global positioning system unit and a fuel level measurement sensor are compared. These data are evaluated and the extent of the influence of the installed devices on the machine fuel consumption is determined from them. Further possibility of exploitation of monitoring of earthmoving machines during excavation and creation of given relief is also described here. Not only the fuel savings were evaluated, but also the accuracy and speed of performed work and thus also the influence of the human factor on performance of earthmoving machines itself.

An Implementation of Drone-Projector: Stabilization of Projected Image

2020 ◽  
Vol 2020 (3) ◽  
pp. 332-1-332-6
Author(s):  
Eunbin Choi ◽  
Younghyeon Park ◽  
Byeungwoo Jeon
Keyword(s):  
Global Positioning System ◽  
Experimental Results ◽  
Positioning System ◽  
Stabilization Method ◽  
Projected Image ◽  
Global Positioning ◽  
The Stability

A drone-projector equipped with a beam projector mounted on a drone has been investigated in order to develop a projector which can overcome restriction of place on which an image is projected. For the stability, the drone-projector requires its mass to be centered, and the additional weights related to projector should be within the payload of the drone. In addition to this requirement, the drone-projector should be designed to minimize the distortion of image caused by 3D translations or rotations of a drone during its hovering due to vibration of propellers, or global positioning system (GPS) errors. In this paper, we consider rotation of a droneprojector which makes the projected image tilted, keystoned, and shifted. To overcome this problem, we propose a software-based stabilization method which pre-corrects the image to be projected based on flight information. Our experimental results show that the distortion of the projected image due to rotations of the proposed drone-projector is attenuated by applying our stabilization method.

scholarly journals Measuring Delays for Bicycles at Signalized Intersections Using Smartphone GPS Tracking Data

2020 ◽  
Vol 9 (3) ◽  
pp. 174 ◽  
Author(s):  
Dominique Gillis ◽  
Sidharta Gautama ◽  
Casper Van Gheluwe ◽  
Ivana Semanjski ◽  
Angel J. Lopez ◽  
...  
Keyword(s):  
Global Positioning System ◽  
Arrival Rate ◽  
Signalized Intersections ◽  
Gps Tracking ◽  
Tracking Data ◽  
Average Delay ◽  
Global Positioning ◽  
Before And After ◽  
Sample Frequency ◽  
Expected Values

The article describes an application of global positioning system (GPS) tracking data (floating bike data) for measuring delays for cyclists at signalized intersections. For selected intersections, we used trip data collected by smartphone tracking to calculate the average delay for cyclists by interpolation between GPS locations before and after the intersection. The outcomes were proven to be stable for different strategies in selecting the GPS locations used for calculation, although GPS locations too close to the intersection tended to lead to an underestimation of the delay. Therefore, the sample frequency of the GPS tracking data is an important parameter to ensure that suitable GPS locations are available before and after the intersection. The calculated delays are realistic values, compared to the theoretically expected values, which are often applied because of the lack of observed data. For some of the analyzed intersections, however, the calculated delays lay outside of the expected range, possibly because the statistics assumed a random arrival rate of cyclists. This condition may not be met when, for example, bicycles arrive in platoons because of an upstream intersection. This justifies that GPS-based delays can form a valuable addition to the theoretically expected values.

scholarly journals Monitoring Sound and Its Perception during the Lockdown and De-Escalation of COVID-19 Pandemic: A Spanish Study

2021 ◽  
Vol 18 (7) ◽  
pp. 3392
Author(s):  
María Dolores Redel-Macías ◽  
Pilar Aparicio-Martinez ◽  
Sara Pinzi ◽  
Pedro Arezes ◽  
Antonio José Cubero-Atienza
Keyword(s):  
Global Positioning System ◽  
Public Transportation ◽  
Online Survey ◽  
Sound Pressure ◽  
Traffic Noise ◽  
Noise Levels ◽  
Environmental Implications ◽  
Spanish Study ◽  
Global Positioning ◽  
Before And After

The lockdown measures in Spain due to the SARS-CoV-2 or COVID-19 (Coronavirus disease 2019) pandemic from 13 March to 21 June 2020 had extensive social and environmental implications. This study aims to understand how the measures of lockdown have influenced noise levels, as well as people’s perception of sound quality before and after lockdown, including de-escalation. For this purpose, an online survey was carried out. Moreover, the noise linked to the Global Positioning System (GPS) position of each individual respondent was recorded aiming to correlate the noise level with the result of the survey. An average reduction of over 30 dB was observed compared with the sound pressure level before lockdown. Furthermore, it was found that the loudness parameter, together with the overall level, increased as the country started relaxing restrictions. Additionally, results showed that the perception of noise quality changed depending on the phase of de-escalation (p < 0.01), the type of property (p < 0.05), and the outside noise (p < 0.01). Moreover, noise annoyance was determined considering age (p < 0.01), gender (p < 0.05), type of property (p < 0.001), and home refurbishment (p < 0.05). It may be concluded that the most important measure to decrease noise levels is the reduction of traffic noise, through using eco-friendly public transportation or bicycles and limiting nightlife hours.

scholarly journals Simulation of Pose to Pose Moving of the Mobile Robot with Specified GPS Points

2020 ◽  
Vol 26 (11) ◽  
pp. 195-208
Author(s):  
Wahab Kareem Yousif ◽  
Ahmed Abdulhsein Ali
Keyword(s):  
Mobile Robot ◽  
Global Positioning System ◽  
Total Error ◽  
Gps Data ◽  
Lyapunov Theorem ◽  
Final Destination ◽  
Global Positioning ◽  
Polar Coordinate ◽  
Data Points ◽  
The Stability

The applications of mobile robots in rescue scenarios, surviving to search, and exploration for outdoor navigation have received increasing attention due to their promising prospects. In this paper, a simulation of a differential wheeled mobile robot was presented, implementing a Global Positioning System (GPS) data points to specified starting points, final destination, and total error. In this work, a simple kinematic controller for polar coordinate trajectory tracking is developed. The tracking between two points, pose to pose, was specified by using the GPS data points. After that, the geodesy (GEO) formulation was used to convert the geodesy coordinate to Euclidean or polar coordinate. The Haversine equation obtained the distance between the two points. The system performance and stability of the tracking controller are proved using the Lyapunov theorem of the stability. A python script was used in this work as a simulator. Computer simulation with pose to pose trajectory strategy conform to the simplicity of the proposed controller.

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