scholarly journals Evaluation of automatic ionogram scaling for use in real-time ionospheric density profile specification: Dourbes DGS-256/ARTIST-4 performance

2012 ◽  
Vol 55 (2) ◽  
Author(s):  
Stanimir M. Stankov ◽  
Jean-Claude Jodogne ◽  
Ivan Kutiev ◽  
Koen Stegen ◽  
René Warnant
Keyword(s):  
Solar Activity ◽  
Real Time ◽  
Local Time ◽  
Density Profile ◽  
Error Bounds ◽  
Statistical Evaluation ◽  
Geomagnetic Storms ◽  
Automatic Scaling ◽  
Time Period ◽  
Analysis Error

<p>Statistical evaluation of the Dourbes (4.6˚E, 50.1˚N) digisonde automatic scaling of the more frequently used ionospheric parameters (foF2, foF1, foE, h’F2, h’F, h’E, and M3000F2) was performed using automatically and manually scaled data from the time period of 2002 to 2008. Automatic scaling was provided in 92% to 94% of cases for most characteristics, except for foF1 (81%). In terms of the automatic scaling accuracy, the magnitude of the residual error for foF2 and M3000F2 (automatically minus manually scaled values) varied according to local time, season, and solar activity. Although geomagnetic storms appear to affect the automatic scaling, the overall results for the influence of geomagnetic activity were inconclusive. Based on this analysis, error bounds were determined (95% probability) for each characteristic: foF2 (–0.75,+0.85), foF1(–0.25,+0.35), foE(–0.35,+0.40), h’F2(–68,+67), h’F(–38,+32), h’E(–26,+2), and M3000F2(–0.55,+0.45).</p>

Latitudinal Dependence of Ionospheric Responses to Some Geomagnetic Storms during Low Solar Activity

2021 ◽  
Vol 61 (3) ◽  
pp. 418-437
Author(s):  
B. W. Joshua ◽  
J. O. Adeniyi ◽  
A. O. Olawepo ◽  
Babatunde Rabiu ◽  
Okoh Daniel ◽  
...  
Keyword(s):  
Solar Activity ◽  
Geomagnetic Storms ◽  
Latitudinal Dependence

Improving Operational Efficiency Using Automated Time Analysis for Multi-Well Pad Fracturing

2021 ◽  
Author(s):  
Fahd Siddiqui ◽  
Mohammadreza Kamyab ◽  
Michael Lowder
Keyword(s):  
Real Time ◽  
Operational Efficiency ◽  
Permian Basin ◽  
Potential Cost ◽  
Time Period ◽  
Cloud Server ◽  
The Us ◽  
Single Well ◽  
Complete Automation

Abstract The economic success of unconventional reservoirs relies on driving down completion costs. Manually measuring the operational efficiency for a multi-well pad can be error-prone and time-prohibitive. Complete automation of this analysis can provide an effortless real-time insight to completion engineers. This study presents a real-time method for measuring the time spent on each completion activity, thereby enabling the identification and potential cost reduction avenues. Two data acquisition boxes are utilized at the completion site to transmit both the fracturing and wireline data in real-time to a cloud server. A data processing algorithm is described to determine the start and end of these two operations for each stage of every well on the pad. The described method then determines other activity intervals (fracturing swap-over, wireline swap-over, and waiting on offset wells) based on the relationship between the fracturing and wireline segments of all the wells. The processed data results can be viewed in real-time on mobile or computers connected to the cloud. Viewing the full operational time log in real-time helps engineers analyze the whole operation and determine key performance indicators (KPIs) such as the number of fractured stages per day, pumping percentage, average fracture, and wireline swap-over durations for a given time period. In addition, the performance of the day and night crews can be evaluated. By plotting a comparison of KPIs for wireline and fracturing times, trends can be readily identified for improving operational efficiency. Practices from best-performing stages can be adopted to reduce non-pumping times. This helps operators save time and money to optimize for more efficient operations. As the number of wells increases, the complexity of manual generation of time-log increases. The presented method can handle multi-well fracturing and wireline operations without such difficulty and in real-time. A case study is also presented, where an operator in the US Permian basin used this method in real-time to view and optimize zipper operations. Analysis indicated that the time spent on the swap over activities could be reduced. This operator set a realistic goal of reducing 10 minutes per swap-over interval. Within one pad, the goal was reached utilizing this method, resulting in reducing 15 hours from the total pad time. The presented method provides an automated overview of fracturing operations. Based on the analysis, timely decisions can be made to reduce operational costs. Moreover, because this method is automated, it is not limited to single well operations but can handle multi-well pad completion designs that are commonplace in unconventionals.

Past participles of strong verbs in Jutland Danish: A real-time study of regionalization and standardization

2012 ◽  
Vol 35 (2) ◽  
pp. 169-195 ◽  
Author(s):  
Torben Juel Jensen ◽  
Marie Maegaard
Keyword(s):  
Real Time ◽  
Geographical Location ◽  
Past Participle ◽  
Time Study ◽  
The Past ◽  
Time Period ◽  
The Status ◽  
Standardization Process ◽  
Large Corpus ◽  
Strong Verbs

The article presents a real-time study of standardization and regionalization processes with respect to the use of past participles of strong verbs in the western part of Denmark. Analyses of a large corpus of recordings of informants from two localities show that the use of the dialectalenform of the past participle suffix has been in decline during the last 30 years. Theenforms are replaced by three other forms, one of which is (partly) dialectal, one regional and one standard Danish. The study indicates that a regionalization process has taken place prior to the time period studied, but that it has now been overtaken by a Copenhagen-based standardization process. The study also shows interesting differences between the two localities, arguably due to the geographical location and size, and to the status of the different participle forms in the traditional local dialects.

scholarly journals Topside equatorial zonal ion velocities measured by C/NOFS during rising solar activity

2014 ◽  
Vol 32 (2) ◽  
pp. 69-75 ◽  
Author(s):  
W. R. Coley ◽  
R. A. Stoneback ◽  
R. A. Heelis ◽  
M. R. Hairston
Keyword(s):  
Solar Activity ◽  
Local Time ◽  
Geomagnetic Field ◽  
General Pattern ◽  
Magnetic Latitude ◽  
Ion Drifts ◽  
F Region ◽  
Westerly Flow ◽  
Solar Local Time ◽  
Ion Velocity

Abstract. The Ion Velocity Meter (IVM), a part of the Coupled Ion Neutral Dynamic Investigation (CINDI) instrument package on the Communication/Navigation Outage Forecast System (C/NOFS) spacecraft, has made over 5 yr of in situ measurements of plasma temperatures, composition, densities, and velocities in the 400–850 km altitude range of the equatorial ionosphere. These measured ion velocities are then transformed into a coordinate system with components parallel and perpendicular to the geomagnetic field allowing us to examine the zonal (horizontal and perpendicular to the geomagnetic field) component of plasma motion over the 2009–2012 interval. The general pattern of local time variation of the equatorial zonal ion velocity is well established as westward during the day and eastward during the night, with the larger nighttime velocities leading to a net ionospheric superrotation. Since the C/NOFS launch in April 2008, F10.7 cm radio fluxes have gradually increased from around 70 sfu to levels in the 130–150 sfu range. The comprehensive coverage of C/NOFS over the low-latitude ionosphere allows us to examine variations of the topside zonal ion velocity over a wide level of solar activity as well as the dependence of the zonal velocity on apex altitude (magnetic latitude), longitude, and solar local time. It was found that the zonal ion drifts show longitude dependence with the largest net eastward values in the American sector. The pre-midnight zonal drifts show definite solar activity (F10.7) dependence. The daytime drifts have a lower dependence on F10.7. The apex altitude (magnetic latitude) variations indicate a more westerly flow at higher altitudes. There is often a net topside subrotation at low F10.7 levels, perhaps indicative of a suppressed F region dynamo due to low field line-integrated conductivity and a low F region altitude at solar minimum.

scholarly journals Towards Real-Time Density Profile Reconstruction With Cuda

2016 ◽  
Author(s):  
Pedro Carvalho ◽  
Diogo R. Ferreira ◽  
Horácio Fernandes ◽  
Luís Meneses
Keyword(s):  
Real Time ◽  
Density Profile ◽  
Profile Reconstruction ◽  
Time Density

scholarly journals Monitoring potential ionospheric changes caused by Van earthquake (Mw 7.2)

2018 ◽  
Author(s):  
Samed Inyurt ◽  
Selcuk Peker ◽  
Cetin Mekik
Keyword(s):  
Solar Activity ◽  
Local Time ◽  
Earthquake Prediction ◽  
Statistical Test ◽  
Van Earthquake ◽  
The North ◽  
The Times ◽  
Geomagnetic Activities

Abstract. Many scientists from different disciplines have studied earthquakes for many years. As a result of these studies, it has been proposed that some changes take place in the ionosphere layer before, during or after earthquakes, and the ionosphere should be monitored in earthquake prediction studies. This study investigates the changes in the ionosphere created by the earthquake with magnitude of Mw=7.2 in the northwest of the Lake Erçek which is located to the north of the province of Van in Turkey on 23 October 2011 and at 1.41 pm local time (−3 UT) with the epicenter of 38.75° N, 43.36° E using the TEC values obtained by the Global Ionosphere Models (GIM) created by IONOLAB-TEC and CODE. In order to see whether the ionospheric changes obtained by the study in question were caused by the earthquake or not, the ionospheric conditions were studied by utilizing indices providing information on solar and geomagnetic activities (F10.7 cm, Kp, Dst). One of the results of the statistical test on the TEC values obtained from the both models, positive and negative anomalies were obtained for the times before, on the day of and after the earthquake, and the reasons for these anomalies are discussed in detail in the last section of the study. As the ionospheric conditions in the analyzed days were highly variable, it was thought that the anomalies were caused by geomagnetic effects, solar activity and the earthquake.

Solar activity and its impact on the mid-latitude trough during geomagnetic storms

2021 ◽  
Author(s):  
Dorota Przepiórka ◽  
Barbara Matyjasiak ◽  
Agata Chuchra ◽  
Hanna Rothkaehl
Keyword(s):  
Solar Activity ◽  
Geomagnetic Activity ◽  
Evolutionary History ◽  
Geomagnetic Storms ◽  
Magnetic Activity ◽  
Topside Ionosphere ◽  
Auroral Region ◽  
Distinct Structure ◽  
Highly Sensitive ◽  
Rapid Changes

&lt;p&gt;Mid-latitude trough (MIT) is the distinct structure observed in Earth&amp;#8217;s ionosphere at high latitudes especially at the nighttimes. The phenomenon is observed at both hemispheres. As it resides at the topside ionosphere in the sub-auroral region, its behaviour and properties are highly sensitive to the solar and geomagnetic activity. Generally as the geomagnetic activity is more pronounced the MIT is observed at lower latitudes, it also deepens and becomes much more distinct in comparison to the low magnetic activity periods. MIT responds as well to the rapid changes in geomagnetic conditions, as are the geomagnetic storms, mainly caused by the CMEs.&amp;#160;&lt;/p&gt;&lt;p&gt;Based on the observations gathered by DEMETER data between 2005 and 2010 years&amp;#160; we present a set of geomagnetic storm cases and how the MIT properties has been changing as the storm evolves. We also discuss how it corresponds to the current solar activity and their evolutionary history&amp;#160; described by a set of different parameters.&lt;/p&gt;

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