RADIO STAR SCINTILLATION NEAR THE AURORAL ZONE

1964 ◽  
Vol 42 (3) ◽  
pp. 458-464 ◽  
Author(s):  
W. D. Ryan

The Queen's University Radio Observatory at Kingston, Ontario, geomagnetic latitude 55° 33′ N, is particularly well situated for radio star scintillation observations looking both north into the auroral zone and south away from the auroral zone. An analysis of the scintillation data has indicated that radio sources observed to the south of the zenith have scintillation characteristics which are typical of observations made at lower geomagnetic latitudes, while sources observed near and to the north of the zenith exhibit the highly disturbed "auroral zone" characteristics. If the scintillation is assumed to be imposed on the incident radiation at a height of 350 kilometers, the transition described above occurs in a north–south distance of about 240 kilometers.


1960 ◽  
Vol 38 (10) ◽  
pp. 1366-1375 ◽  
Author(s):  
J. A. Kim ◽  
B. W. Currie

A previous paper showed that systematic motions of aurora parallel and normal to the geomagnetic meridians could be deduced from successions of all-sky camera photographs. More reliable deductions which are based on a much larger number of observations, including some from a station inside the auroral zone, are reported in this paper. Both southward and northward speeds increase with geomagnetic latitude to the auroral zone where they become constant, or even decrease slightly, before continuing to increase inside the auroral zone. A seasonal variation of north–south speeds does not appear to exist. A diurnal variation of north–south speeds, dependent on geomagnetic latitude, is evident, the speeds decreasing to a minimum during the morning hours to the south of the auroral zone and increasing to a maximum during the same hours to the north of the zone. Large positive correlations exist between north–south speeds and departures of the magnetic field intensity from normal. East–west speeds either decrease or remain constant with increasing geomagnetic latitude. A significant seasonal variation of east–west speeds is not evident. Eastward speeds are at a maximum between 03 and 04 hours L.M.T., and are associated with negative magnetic bays; westward speeds, between 21 and 22 hours L.M.T., and are associated with positive magnetic bays.



1959 ◽  
Vol 9 ◽  
pp. 487-491 ◽  
Author(s):  
S. Archer ◽  
J. E. Baldwin ◽  
D. O. Edge ◽  
B. Elsmore ◽  
P. A. G. Scheuer ◽  
...  

Two years ago the Cambridge 4-aerial interferometer [1] was adapted to work at a frequency of 159 Mc/s, the resolving power thereby being increased by a factor of four over that at the previous frequency, 81.5 Mc/s. The overall beamwidth at 159 Mc/s is 1.2 degrees by 7 degrees but the beam contains interference fringes in two planes at right angles, so that, by phase-switching between the east pair and the west pair of aerials, sources with angular diameters greater than about 7 minutes of arc are eliminated. A survey using this technique has been carried out by Edge and Shakeshaft and may be called a “small diameter” survey. If the phase-switching receiver is connected between the north pair and the south pair of aerials it is possible to record sources with diameters up to about 1 degree and to measure diameters between 2 and 8 minutes of arc. Archer and Baldwin have used the aerial in this way to make a “large diameter” survey. These two surveys will be referred to collectively as the 3C survey.



Data ◽  
2021 ◽  
Vol 6 (6) ◽  
pp. 57
Author(s):  
Hassan Gholami ◽  
Harald Nils Røstvik

The prosperous implementation of Building Integrated Photovoltaics (BIPV), as well as Building Attached Photovoltaics (BAPV), needs an accurate and detailed assessment of the potential of solar irradiation and electricity production of various commercialised technologies in different orientations on the outer skins of the building. This article presents a dataset for the solar incident radiation and electricity production of PV systems in the north and south orientations in a dense urban area (in the northern hemisphere). The solar incident radiation and the electricity production of two back-to-back PV panels with a ten-centimetre gap for one year are monitored and logged as primary data sources. Using Microsoft Excel, both panels’ efficiency is also presented as a secondary source of data. The implemented PV panels are composed of polycrystalline silicon cells with an efficiency of 16.9%. The results depicted that the actual efficiency of the south-facing panel (13%–15%) is always closer to the standard efficiency of the panel compared to the actual efficiency of the north-facing panel (8%–12%). Moreover, although the efficiency of the south-facing panel on sunny days of the year is almost constant, the efficiency of the north-facing panel decreases significantly in winter. This phenomenon might be linked to the spectral response of the polycrystalline silicon cells and different incident solar radiation spectrum on the panels. While the monitored data cover the radiation and system electricity production in various air conditions, the analysis is mainly conducted for sunny days, and more investigation is needed to analyse the system performance in other weather conditions (like cloudy and overcast skies). The presented database could be used to analyse the performance of polycrystalline silicon PV panels and their operational efficiency in a dense urban area and for different orientations.



2000 ◽  
Vol 179 ◽  
pp. 201-204
Author(s):  
Vojtech Rušin ◽  
Milan Minarovjech ◽  
Milan Rybanský

AbstractLong-term cyclic variations in the distribution of prominences and intensities of green (530.3 nm) and red (637.4 nm) coronal emission lines over solar cycles 18–23 are presented. Polar prominence branches will reach the poles at different epochs in cycle 23: the north branch at the beginning in 2002 and the south branch a year later (2003), respectively. The local maxima of intensities in the green line show both poleward- and equatorward-migrating branches. The poleward branches will reach the poles around cycle maxima like prominences, while the equatorward branches show a duration of 18 years and will end in cycle minima (2007). The red corona shows mostly equatorward branches. The possibility that these branches begin to develop at high latitudes in the preceding cycles cannot be excluded.





Author(s):  
Esraa Aladdin Noori ◽  
Nasser Zain AlAbidine Ahmed

The Russian-American relations have undergone many stages of conflict and competition over cooperation that have left their mark on the international balance of power in the Middle East. The Iraqi and Syrian crises are a detailed development in the Middle East region. The Middle East region has allowed some regional and international conflicts to intensify, with the expansion of the geopolitical circle, which, if applied strategically to the Middle East region, covers the area between Afghanistan and East Asia, From the north to the Maghreb to the west and to the Sudan and the Greater Sahara to the south, its strategic importance will seem clear. It is the main lifeline of the Western world.



Author(s):  
A., C. Prasetyo

Overpressure existence represents a geological hazard; therefore, an accurate pore pressure prediction is critical for well planning and drilling procedures, etc. Overpressure is a geological phenomenon usually generated by two mechanisms, loading (disequilibrium compaction) and unloading mechanisms (diagenesis and hydrocarbon generation) and they are all geological processes. This research was conducted based on analytical and descriptive methods integrated with well data including wireline log, laboratory test and well test data. This research was conducted based on quantitative estimate of pore pressures using the Eaton Method. The stages are determining shale intervals with GR logs, calculating vertical stress/overburden stress values, determining normal compaction trends, making cross plots of sonic logs against density logs, calculating geothermal gradients, analyzing hydrocarbon maturity, and calculating sedimentation rates with burial history. The research conducted an analysis method on the distribution of clay mineral composition to determine depositional environment and its relationship to overpressure. The wells include GAP-01, GAP-02, GAP-03, and GAP-04 which has an overpressure zone range at depth 8501-10988 ft. The pressure value within the 4 wells has a range between 4358-7451 Psi. Overpressure mechanism in the GAP field is caused by non-loading mechanism (clay mineral diagenesis and hydrocarbon maturation). Overpressure distribution is controlled by its stratigraphy. Therefore, it is possible overpressure is spread quite broadly, especially in the low morphology of the “GAP” Field. This relates to the delta depositional environment with thick shale. Based on clay minerals distribution, the northern part (GAP 02 & 03) has more clay mineral content compared to the south and this can be interpreted increasingly towards sea (low energy regime) and facies turned into pro-delta. Overpressure might be found shallower in the north than the south due to higher clay mineral content present to the north.



2019 ◽  
Author(s):  
Hamed D. Ibrahim

North and South Atlantic lateral volume exchange is a key component of the Atlantic Meridional Overturning Circulation (AMOC) embedded in Earth’s climate. Northward AMOC heat transport within this exchange mitigates the large heat loss to the atmosphere in the northern North Atlantic. Because of inadequate climate data, observational basin-scale studies of net interbasin exchange between the North and South Atlantic have been limited. Here ten independent climate datasets, five satellite-derived and five analyses, are synthesized to show that North and South Atlantic climatological net lateral volume exchange is partitioned into two seasonal regimes. From late-May to late-November, net lateral volume flux is from the North to the South Atlantic; whereas from late-November to late-May, net lateral volume flux is from the South to the North Atlantic. This climatological characterization offers a framework for assessing seasonal variations in these basins and provides a constraint for climate models that simulate AMOC dynamics.



Author(s):  
Andrei Sokolov ◽  
Andrei Sokolov ◽  
Boris Chubarenko ◽  
Boris Chubarenko

Three dumping sites located at the south-eastern part of the Baltic Sea (Kaliningrad Oblast) at shallow depths are considered. The first one is located to the south of the Vistula Lagoon inlet in front of a permanently eroded open marine shore segment. The second one is located to the north of the Vistula Lagoon inlet, and is used now for disposing of dredged material extracted from the Kaliningrad Seaway Canal. The third dumping site is located near the northern shore of the Sambian Peninsula to the east of the Cape Gvardeijski and assigned for disposing the dredged material extracted from the fairway to the Pionerskij Port located nearby. The last site is planned to be used for disposing of dredged material from the future port that should be constructed there before the beginning of the FIFA World Cup 2018. All three dumping sites are located not far from the eroded segments of the shore. The question behind the study is: would it possible that disposed material will naturally transported from the damping site to the shore and accumulate there to protect it from erosion? A numerical hydrodynamic-transport 3D model (MIKE) was used to model sediment transport under different wind actions. The winds with the speed stronger than 15 m/s complete wash out disposed material from the dumping site and spreading it over the wide area with a negligible layer thickness. Winds of about 7-10 m/s transport material along the shore at a distance of few kilometers that may be useful for shore protection. The first location of the dumping site (to the south of the Vistula Lagoon inlet) looks very ineffective for potential protection the shore nearby. At the other hand, the second and especially the third locations are favorable for transport of disposed material to the shore, the most favorable conditions are at onshore or alongshore currents.



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