scholarly journals Event-triggered sampled-data energy control of a pendulum * *This work was supported by Saint Petersburg State University, (grant 6.38.230.2015) and by Government of Russian Federation, Grant 074-U01. The proof of avoidance of Zeno phenomenon in continuous event-trigger was performed in IPME RAS under support of Russian Science Foundation (grant 14-29-00142). The results for event-trigger with a constant threshold (Proposition 2) was performed under support of the Russian Foundation for Basic Research, Grant 17-01-00102-a

2017 ◽  
Vol 50 (1) ◽  
pp. 15295-15300 ◽  
Author(s):  
Ruslan Seifullaev ◽  
Alexander Fradkov ◽  
Emilia Fridman
Keyword(s):  
Basic Research ◽  
State University ◽  
Sampled Data ◽  
Russian Science ◽  
Energy Control ◽  
Saint Petersburg ◽  
Event Trigger ◽  
Basic Research Grant ◽  
Event Triggered ◽  
Research Grant

scholarly journals Clustering the performance efficiency of Russian scientists in the natural sciences

2018 ◽  
pp. 76-91 ◽  
Author(s):  
Valery Arutyunov ◽  
Nataliya Grishina
Keyword(s):  
Citation Index ◽  
Basic Research ◽  
Natural Sciences ◽  
Computer Engineering ◽  
Russian Science ◽  
Scientific Performance ◽  
Russian Science Citation Index ◽  
Study Results ◽  
Basic Research Grant ◽  
Research Grant

The authors prove, on the basis of the analysis, that no one full-scale study of scientific performance of the organizations and researchers in the natural science has been conducted in the Russia. They propose to project the study of the publication flow in about 30 disciplines within the natural sciences based on the data of the Russian Science Citation Index to analyze the performance of Russian scientists and to obtain new knowledge on leading regional scientific clusters, organizations and personalia. The findings of the study, based on the Hirsch index and other citation indicators would enable to evaluate the Russia’s contribution into the disciplines in the form of the demanded and cited study results. The data for three disciplines are presented, namely: informatics, cybernetics, and computer engineering, supplemented with the ranking lists of Russian organizations with maximum values of citation and Hirsch indexes. The article is complemented with the tables. The article is prepared through the support of the Russian Foundation for Basic Research, Grant No. 18-07-00036.

New absolute paleointensity results from ~250 Ma Kuznetsk basalts. Weak versus strong geomagnetic field at the P-T boundary.

2020 ◽  
Author(s):  
Andrey Eliseev ◽  
Nikolay Mikhaltsov ◽  
Evgeniy Kulakov
Keyword(s):  
Basic Research ◽  
Linear Segment ◽  
Russian Science ◽  
Southern Siberia ◽  
Magnetic Remanence ◽  
Magnetic Analysis ◽  
Individual Grains ◽  
Basic Research Grant ◽  
Curie Temperatures ◽  
Research Grant

<p>We present absolute paleointensity results obtained from a collection of samples from ~250 Ma Kuznetsk Traps (Kuznetsk Depression, Southern Siberia). In addition to similar age these rocks display geochemical signatures similar to those reported for basalts of Siberan Traps and represent the southernmost affinity of the latter.</p><p>The primary nature of magnetic remanence in studied rocks was established by previous paleomagnetic studies Rock magnetic analysis indicates that the main magnetic mineral is titanomagnetite in a predominantly single-domain state with Curie temperatures between ~275 and 350⁰C. Scanning electron microscopy showed that titanomagnetite grains range in size from 0.5 to 1 μm. Individual grains are separated from each other and “sealed” within silicate matrix, which largely predetermined perfect preservation of primary mineral textures.</p><p>Paleointensity estimates were obtained using the Coe-version of Thellier-Thellier double-heating protocol with partial TRM checks. 36 samples (5 sites taken along the Tom River) yielded straight Arai-Nagata diagrams within temperature interval between 100 to 275⁰C. The average paleointensity value obtained from these samples was calculated at 12.7 ± 1 µT (with a factor q of about 11) with corresponding VDM=2.1 ± 0.2 × 10<sup>22</sup> Am<sup>2</sup>.</p><p>Arai-Nagata diagrams for 20 samples from two other sites (collected in quarries on the Karakansky ridge) display more complex behavior. Straight linear segment of Arai plots between ~100 and 300⁰C yielded an average paleointensity value of 44 ± 1 μT, which corresponds to a VDM=7.0 ± 0.1 × 10<sup>22</sup> Am<sup>2</sup>. However on higher temperatures, NRM vs. TRM data have a trend of flattening that increase in artificial TRM is accompanied by no loss of NRM. We interpret this observation as a result of laboratory-induced thermochemical alteration, namely, unmixing of homogeneous Ti-magnetites into Ti-rich and Fe-rich phases, with the latter phase responsible for such NRM-lost vs. TRM-gained behavior. Thermomagnetic analyses on these samples indicated mineralogical changes that set approximately at 300⁰C, supporting our interpretation. However, reversible thermomagnetic curves and p-TRM checks within 10% from initial pTRM, below ~300⁰C suggest that paleointensities determined between ~100 and 300 ⁰C of Arai plots are trustworthy.</p><p>We will discuss our results and reasons for such radical differences between paleointensity estimates obtained from the same suite of rocks sampled at different locations.</p><p>The study was supported by the Russian Foundation for Basic Research, grant No. 18-05-00234 and the Russian Science Foundation, grant No. 19-17-00091.</p>

Secular geomagnetic field variations in Bulgarian lands during Classical Age and Late Antiquity – new archaeomagnetic data

2021 ◽  
Author(s):  
Maria Kostadinova-Avramova ◽  
Petar Dimitrov ◽  
Andrei Kosterov ◽  
Mary Kovacheva
Keyword(s):  
Material Culture ◽  
Late Antiquity ◽  
Basic Research ◽  
Reference Points ◽  
Archaeological Sites ◽  
Historical Sources ◽  
National Science ◽  
Basic Research Grant ◽  
National Science Fund ◽  
Research Grant

<p>Numerous historical sources and archaeological monuments attest the age of Antiquity in Bulgaria – from both the early Roman period (I – III c.) and Late Antiquity (IV – VI c.). Owing to systematic archaeological excavations, lasting more than 100 years, plenty of information has been accumulated concerning not only all aspects and manifestations of its material culture, but also their evolution and chronology.  This in turn allows for interdisciplinary fields such as archaeomagnetism to progress.</p><p>There are many archaeomagnetically studied archaeological structures from the Antiquity. The results included in the Bulgarian database form 74 reference points. However, only 20 of them are full-vector determinations because 70 % of the investigated materials are bricks. Hence, the secular variation of declination is poorly constrained within the considered period. Moreover, the reuse of bricks in the constructions occurred quite often (especially in the Late Antiquity) providing for possible errors in archaeological dating. In addition, stronger effects of magnetic anisotropy and cooling rate are usually expected for bricks than for hearths, domestic ovens, production kilns or burnt dwelling remains (there are no results from pottery in the Bulgarian dataset) and both factors are not evaluated for most of the older results. All this can explain the contradictions observed between some of the experimental results juxtaposed over the absolute time scale. In an attempt to clarify these contradictions 13 baked clay structures from eight archaeological sites were archaeomagnetically studied producing seven new directional and eight new intensity data. The samples collected possess variable magnetic properties suggesting differences in clay sources and/or firing conditions. Magnetically soft minerals prevail in seven structures but in the remaining six, abundant HCSLT phase is detected. The success rate of archaeointensity determination experiments vary from 49 to 100 %. It appears that samples containing HCSLT phase always produces good araeointensity results unlike those with the dominant presence of soft carriers.</p><p>The new reference points are compared with the present compilation of Bulgarian archaeomagnetic dataset and with the data from the neighboring countries.</p><p> </p><p>This study is supported by the grant KP-06-Russia-10 from the Bulgarian National Science Fund and Russian Foundation of the Basic Research grant 19-55-18006.</p>

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