scholarly journals Statistical study of the night-time F-layer dynamics at the magnetic equator in West Africa during the solar minimum period 1995–1997

2015 ◽  
Vol 33 (1) ◽  
pp. 143-157 ◽  
Author(s):  
K. S. Tanoh ◽  
B. J.-P. Adohi ◽  
I. S. Coulibaly ◽  
C. Amory-Mazaudier ◽  
A. T. Kobea ◽  
...  
Keyword(s):  
Solar Minimum ◽  
Transition Process ◽  
The Other ◽  
Winter Period ◽  
Night Time ◽  
Minimum Period ◽  
Bottom Part ◽  
Layer Height ◽  
Northern Summer ◽  
The One

Abstract. In this paper, we report on the night-time equatorial F-layer height behaviour at Korhogo (9.2° N, 5° W; 2.4° S dip lat), Ivory Coast, in the West African sector during the solar minimum period 1995–1997. The data were collected from quarter-hourly ionograms of an Ionospheric Prediction Service (IPS) 42-type vertical sounder. The main focus of this work was to study the seasonal changes in the F-layer height and to clarify the equinox transition process recently evidenced at Korhogo during 1995, the year of declining solar flux activity. The F-layer height was found to vary strongly with time, with up to three main phases. The night-to-night variability of these morphological phases was then analysed. The early post-sunset slow rise, commonly associated with rapid chemical recombination processes in the bottom part of the F layer, remained featureless and was observed regardless of the date. By contrast, the following event, either presented like the post-sunset height peak associated with the evening E × B drift, or was delayed to the midnight sector, thus involving another mechanism. The statistical analysis of the occurrence of these events throughout the solar minimum period 1995–1997 revealed two main F-layer height patterns, each characteristic of a specific season. The one with the post-sunset height peak was associated with the northern winter period, whereas the other, with the midnight height peak, characterized the northern summer period. The transition process from one pattern to the other took place during the equinox periods and was found to last only a few weeks. We discuss these results in the light of earlier works.

scholarly journals Artificially Induced Phase Scintillation Observed From GLONASS Signals

2021 ◽  
Author(s):  
Abdollah Darya ◽  
Muhammad Shaikh ◽  
Ilias Fernini ◽  
Hamid AlNaimiy
Keyword(s):  
Remote Sensing ◽  
Solar Minimum ◽  
Elevated Level ◽  
The Other ◽  
Scintillation Index ◽  
Satellite Constellations ◽  
Minimum Period ◽  
Positioning Accuracy ◽  
Phase Lock ◽  
Future Studies

The phase scintillation index is a commonly used metric in the remote sensing of ionospheric irregularities. In this work, we analyze the phase scintillation index observed from the GPS, GLONASS, Galileo, and BeiDou satellite constellations, for a continuous period of three years. Our analysis reveals an elevated level of L1 phase scintillation observed from most GLONASS satellites, and non of the other GNSS constellations during the same period. This is of particular interest as the abnormality was observed during a solar minimum period, and from satellites labeled as healthy. Furthermore, the observations made were verified with data from three other receivers in different regions. This study was conducted to highlight these artificially induced phase scintillations from GLONASS satellites so that future studies can take them into considerations, especially during periods of heightened geomagnetic activity. Additionally, these artificially induced phase scintillations may result in loss of phase lock, as well as reduced positioning accuracy, which may have serious effects on the reliability and integrity of the GLONASS positioning service.

scholarly journals EUNUS: THE COWARDLY KING

2013 ◽  
Vol 63 (1) ◽  
pp. 237-252 ◽  
Author(s):  
Peter Morton
Keyword(s):  
Historical Context ◽  
Status Quo ◽  
The Other ◽  
Night Time ◽  
Slave Owner ◽  
Other Hand ◽  
Diodorus Siculus ◽  
The Status ◽  
The One ◽  
The City

In 135b.c., unable to endure the treatment of their master Damophilus, a group of slaves, urged on by the wonder-worker Eunus, captured the city of Enna in Eastern Sicily in a night-time raid. The subsequent war, according to our sources the largest of its kind in antiquity, raged for three years, destroying the armies of Roman praetors, and engaging three consecutive consuls in its eventual suppression. The success of the rebels in holding out for years against a progression of Roman armies indicates the importance of the event, and the capabilities of their leaders. One expects the man capable of leading such a revolt to have been exceptional, and in this respect the ancient accounts do not disappoint: in a narrative replete with larger-than-life characters, ranging from the depraved slave-owner Damophilus (Diod. Sic. 34/5.2.10, 35–8) to the restrained Roman consul Calpurnius Piso (Val. Max. 4.3.10), one figure stands out in Diodorus Siculus' depiction: the leader of the slaves. This man, Eunus, whom Diodorus describes as the leader of the event he calls the (first) Sicilian Slave War, has been variously interpreted in modern scholarship. Analyses have fallen into two (not mutually exclusive) categories. On the one hand, the hostile and outlandish account of Diodorus is accepted uncritically, with the details of Eunus' character understood as faithful, historical representations. On the other hand, the negative facets of Eunus' character are reinterpreted in a positive historical context, thereby outlining his suitability and capability to lead such a large and successful insurgency against Rome. Indeed, Urbainczyk recently argued that despite the difficulties in saying anything definite about the leaders of the so-called Sicilian Slave Wars ‘[Diodorus] attributed to [Eunus] all the powers, abilities, wisdom, and cunning that challenges to the status quo had to have in order to succeed’.

scholarly journals <i>Letter to the Editor</i>: Post-midnight onset of spread-F at Kodaikanal during the June solstice of solar minimum

1999 ◽  
Vol 17 (8) ◽  
pp. 1111-1115 ◽  
Author(s):  
J. H. Sastri
Keyword(s):  
Solar Activity ◽  
Solar Minimum ◽  
Equatorial Ionosphere ◽  
Instability Mechanism ◽  
Layer Height ◽  
Northern Summer ◽  
June Solstice ◽  
Spread F ◽  
Rayleigh Taylor Instability ◽  
Distinct Increase

Abstract. At dip equatorial stations in the Indian zone, spread-F conditions are known to develop preferentially around midnight during the June solstice (northern summer) months of low solar activity, in association with a distinct increase in F layer height. It is currently held that this onset of spread-F far away from the sunset terminator is due to the generalised Rayleigh-Taylor instability mechanism, with the gravitational and cross-field instability factors (and hence F layer height) playing important roles. We have studied the quarter-hourly ionograms of Kodaikanal (10.2°N; 77.5°E; dip 4°N) for the northern summer months (May-August) of 1994 and 1995 to ascertain the ambient ionospheric conditions against which the post-midnight onset of spread-F takes place. A data sample of 38 nights with midnight onset of spread-F and 34 nights without spread-F is used for the purpose. It is found that a conspicious increase in F layer height beginning around 2100 LT occurs on nights with spread-F as well as without spread-F. This feature is seen in the nocturnal pattern of F layer height on many individual nights as well as of average F layer height for the two categories of nights. The result strongly suggests that the F layer height does not play a pivotal role in the midnight onset of spread-F during the June solstice of solar minimum. The implications of this finding are discussed.Key words. Ionosphere (equatorial ionosphere; ionospheric irregularities)

scholarly journals Integrated efficiency evaluation of the heat- supplying enterprises activity

2020 ◽  
Vol 164 ◽  
pp. 01024
Author(s):  
Evgeny Еvseev ◽  
Tatiana Kisel
Keyword(s):  
Heat Supply ◽  
Climatic Conditions ◽  
Living Environment ◽  
The Other ◽  
Winter Period ◽  
Thermal Mode ◽  
Efficiency Evaluation ◽  
Cold Winter ◽  
External Stakeholders ◽  
The One

Heat supply is the industry which forms the comfortable living environment in many respects. It is especially felt in those regions, where climatic conditions demand maintenance of the comfortable thermal mode during the cold winter period. On the one hand, the efficiency of the heat- supplying enterprises activity determines the level of the population comfort, including temperature condition in rooms, uninterrupted heat supply, on the other hand, it influences the tariff level for heat supply services. The article presents the results of the research, which purpose was to reveal the indicators of the heat-supplying enterprises activity, allowing to estimate their efficiency in the most complete way from the position of various stakeholders. The system of indicators, created as a result of the conducted research, can be used by both management of the enterprise, and external stakeholders for the efficiency evaluation of the heat-supplying enterprise in statics and in dynamics.

Design Mind or Laws of Nature: Space, Vital and Social Reality

2021 ◽  
Vol 13 (2-1) ◽  
pp. 143-164
Author(s):  
Vadim Rozin ◽  
Keyword(s):  
Social Action ◽  
Laws Of Nature ◽  
Transition Process ◽  
The Other ◽  
Second Nature ◽  
Different Types ◽  
The Origin Of Life ◽  
The One ◽  
The 19Th Century ◽  
First Nature

The article is devoted to the consideration of two interrelated topics: the opposition of two foundations of social action, one of which is called the ‘design mind’ by the author, and the other is known as ‘nature’, and the path of evolution, in which three types of realities arose sequentially - cosmic, vital (biological) and social. The discourse of the design mind is formed in ancient culture in the works of Plato, and the concept of nature in the works of Aristotle. The first is characterized by the predominance of ideas and patterns, as well as a belief in the possibility of their implementation. The second is characterized by considering the prevailing reality (nature) and mediating social action by knowledge of the processes of nature. The new European understanding of nature is a hybrid; it combines the Aristotelian and Platonic approaches. Nature is both actions in nature and design creation. The second difference is that the new European nature was understood as “written in the language of mathematics” and passed through experimentation. However, since the 19th century, the natural-scientific understanding of nature has been criticized and differentiated: a demarcation is made between the first and second nature, different types of realities, nature and technology. Within the framework of this process, in the course of explaining the origin of life, man and society, a diagram of the evolution of three types of realities is outlined: first, there is only cosmic reality, understood as the first nature, then comes vital reality, and then social (second nature). An assumption is introduced that the next type of reality in evolution appears as a new formation, on the one hand, as a result of development and complication, and on the other, as a number of random processes. The conditions of interaction of processes belonging to different types of reality are discussed; in this regard, the concepts of “renegade areas” and “maternal reality” are introduced. On the basis of the outlined distinctions and relationships, an explanation of the pandemic and the modern transition process from modernity to post-culture is proposed.

scholarly journals One-Day-Shock, Two-Days-Shock and Three-Days-Shocks foF2 Diurnal Variation with Solar Cycle Phases at Ouagadougou Station from 1966 to 1998. Comparison with IRI 2012 Predictions

2019 ◽  
Vol 12 (1) ◽  
pp. 38
Author(s):  
Abdoul-kader SEGDA ◽  
Doua Allain GNABAHOU ◽  
Frédéric OUATTARA
Keyword(s):  
Solar Cycle ◽  
Time Variation ◽  
Solar Minimum ◽  
The Other ◽  
Cycle Phase ◽  
Minimum Phase ◽  
Solar Cycles ◽  
Night Time ◽  
Maximum Phase ◽  
Phase Dependence

The present work concerns foF2 time variation at Ouagadougou station for three solar cycles (from cycle 20 to cycle 22). We not only investigate solar cycle phase dependence under shock activity that is divided into one-shock-activity, two-shock-activity and three-shock-activity but also compare the IRI 2012 model values with the data carried out at Ouagadougou station. This study reveals that there is no one-day-shock during solar minimum phase. For the other solar cycle phases IRI 2012 reproduces the ionosphere electrodynamics at daytime except during the increasing phase. During night time the model is not suitable. The best subroutine under one-day-shock activity is URSI for increasing and decreasing phases. During the maximum phase it is CCIR. For two-days-shock activity IRI 2012 reproduces the ionosphere electrodynamics during the minimum and the increasing phases. The best subroutine is CCIR during the minimum phase and URSI for the other solar cycle phases. For three-days-shock activity IRI 2012 is not suitable. The best model is URSI for all solar cycle phases.

scholarly journals Artificially Induced Phase Scintillation Observed From GLONASS Signals

2021 ◽  
Author(s):  
Abdollah Darya ◽  
Muhammad Shaikh ◽  
Ilias Fernini ◽  
Hamid AlNaimiy
Keyword(s):  
Remote Sensing ◽  
Solar Minimum ◽  
Elevated Level ◽  
The Other ◽  
Scintillation Index ◽  
Satellite Constellations ◽  
Minimum Period ◽  
Positioning Accuracy ◽  
Phase Lock ◽  
Future Studies

The phase scintillation index is a commonly used metric in the remote sensing of ionospheric irregularities. In this work, we analyze the phase scintillation index observed from the GPS, GLONASS, Galileo, and BeiDou satellite constellations, for a continuous period of three years. Our analysis reveals an elevated level of L1 phase scintillation observed from most GLONASS satellites, and non of the other GNSS constellations during the same period. This is of particular interest as the abnormality was observed during a solar minimum period, and from satellites labeled as healthy. Furthermore, the observations made were verified with data from three other receivers in different regions. This study was conducted to highlight these artificially induced phase scintillations from GLONASS satellites so that future studies can take them into considerations, especially during periods of heightened geomagnetic activity. Additionally, these artificially induced phase scintillations may result in loss of phase lock, as well as reduced positioning accuracy, which may have serious effects on the reliability and integrity of the GLONASS positioning service.

Note on Selection of Coordinate Systems for Geodynamics

1975 ◽  
Vol 26 ◽  
pp. 395-407
Author(s):  
S. Henriksen
Keyword(s):  
Sea Level ◽  
The Other ◽  
Coordinate Systems ◽  
Mean Sea Level ◽  
The Earth ◽  
The One ◽  
Static Systems ◽  
Selection Of

The first question to be answered, in seeking coordinate systems for geodynamics, is: what is geodynamics? The answer is, of course, that geodynamics is that part of geophysics which is concerned with movements of the Earth, as opposed to geostatics which is the physics of the stationary Earth. But as far as we know, there is no stationary Earth – epur sic monere. So geodynamics is actually coextensive with geophysics, and coordinate systems suitable for the one should be suitable for the other. At the present time, there are not many coordinate systems, if any, that can be identified with a static Earth. Certainly the only coordinate of aeronomic (atmospheric) interest is the height, and this is usually either as geodynamic height or as pressure. In oceanology, the most important coordinate is depth, and this, like heights in the atmosphere, is expressed as metric depth from mean sea level, as geodynamic depth, or as pressure. Only for the earth do we find “static” systems in use, ana even here there is real question as to whether the systems are dynamic or static. So it would seem that our answer to the question, of what kind, of coordinate systems are we seeking, must be that we are looking for the same systems as are used in geophysics, and these systems are dynamic in nature already – that is, their definition involvestime.

Stories and the Self

2020 ◽  
Vol 32 (2) ◽  
pp. 47-58 ◽  
Author(s):  
Stefan Krause ◽  
Markus Appel
Keyword(s):  
Meta Analysis ◽  
The Self ◽  
The Other ◽  
Lower Degree ◽  
Contrast Effects ◽  
Self Perception ◽  
Self Perceptions ◽  
Other Hand ◽  
The One ◽  
Implicit And Explicit

Abstract. Two experiments examined the influence of stories on recipients’ self-perceptions. Extending prior theory and research, our focus was on assimilation effects (i.e., changes in self-perception in line with a protagonist’s traits) as well as on contrast effects (i.e., changes in self-perception in contrast to a protagonist’s traits). In Experiment 1 ( N = 113), implicit and explicit conscientiousness were assessed after participants read a story about either a diligent or a negligent student. Moderation analyses showed that highly transported participants and participants with lower counterarguing scores assimilate the depicted traits of a story protagonist, as indicated by explicit, self-reported conscientiousness ratings. Participants, who were more critical toward a story (i.e., higher counterarguing) and with a lower degree of transportation, showed contrast effects. In Experiment 2 ( N = 103), we manipulated transportation and counterarguing, but we could not identify an effect on participants’ self-ascribed level of conscientiousness. A mini meta-analysis across both experiments revealed significant positive overall associations between transportation and counterarguing on the one hand and story-consistent self-reported conscientiousness on the other hand.

Radioimmunotherapy for treatment of acute myeloid leukaemia and myelodysplastic syndrome

2005 ◽  
Vol 44 (03) ◽  
pp. 107-117
Author(s):  
R. G. Meyer ◽  
W. Herr ◽  
A. Helisch ◽  
P. Bartenstein ◽  
I. Buchmann
Keyword(s):  
Acute Myeloid Leukaemia ◽  
Myeloid Leukaemia ◽  
Primary Tumour ◽  
The Other ◽  
Haematopoietic Stem Cell ◽  
Other Hand ◽  
Primary Reduction ◽  
The One ◽  
Acute Myeloid

SummaryThe prognosis of patients with acute myeloid leukaemia (AML) has improved considerably by introduction of aggressive consolidation chemotherapy and haematopoietic stem cell transplantation (SCT). Nevertheless, only 20-30% of patients with AML achieve long-term diseasefree survival after SCT. The most common cause of treatment failure is relapse. Additionally, mortality rates are significantly increased by therapy-related causes such as toxicity of chemotherapy and complications of SCT. Including radioimmunotherapies in the treatment of AML and myelodyplastic syndrome (MDS) allows for the achievement of a pronounced antileukaemic effect for the reduction of relapse rates on the one hand. On the other hand, no increase of acute toxicity and later complications should be induced. These effects are important for the primary reduction of tumour cells as well as for the myeloablative conditioning before SCT.This paper provides a systematic and critical review of the currently used radionuclides and immunoconjugates for the treatment of AML and MDS and summarizes the literature on primary tumour cell reductive radioimmunotherapies on the one hand and conditioning radioimmunotherapies before SCT on the other hand.

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