scholarly journals Research of Bibliographic References in Math-Net.Ru using the Journal Citation Graph

2021 ◽  
Vol 24 (5) ◽  
pp. 923-943
Author(s):  
Андрей Анатольевич Печников ◽  
Дмитрий Евгеньевич Чебуков

According to the portal Math-Net.Ru a graph of journal citation is constructed. To increase the reliability of the model, the citation time interval was chosen from 2010 to 2021, when the distribution of citation articles stabilized at the level of 3500-4500 citations per year. The structure of link aging is studied and it is shown that their half-life is equal to 8 years. Therefore, the publication date of the cited articles was limited to 2002. For the constructed citation graph, the main properties, such as a small diameter and a high density, are obtained, indicating a high level of scientific communication in the Math-Net.Ru. The absence of the “Matthew effect” as a pronounced advantage in quoting established journals in relation to less well-known ones is shown. Adequacy of the journal citation graph Math-Net.Ru as a model of scientific communication confirmed by comparing the ranking of journals in the citation graph with their SCIENCE INDEX rating in eLIBRARY.RU. A direct moderate relationship between the two rankings is shown. A number of meaningful conclusions are drawn from the analysis of the citation graph.

2021 ◽  
Author(s):  
Andrey Anatolievich Pechnikov ◽  
Dmitry Evgenievch Chebukov

According to the portal Math-Net.Ru a graph of journal citation is constructed. To increase the reliability of the model, the citation time interval was chosen from 2010 to 2021, when the distribution of citation articles stabilized at the level of 3500-4500 citations per year. The structure of link aging is studied and it is shown that their half-life is equal to 8 years. Therefore, the publication date of the cited articles was limited to 2002. For the constructed citation graph, the main properties, such as a small diameter and a high density, are obtained, indicating a high level of scientific communication in the Math-Net.Ru. Adequacy of the journal citation graph Math-Net.Ru as a model of scientific communication confirmed by comparing the ranking of journals in the citation graph with their SCIENCE INDEX rating in eLIBRARY.RU. A direct moderate relationship between the two rankings is shown. A number of meaningful conclusions are drawn from the analysis of the citation graph.


2021 ◽  
Vol 16 (1(21)) ◽  
pp. 22-31
Author(s):  
David Bidzinashvili

The new Corona-virus and the contagious disease which it causes, the so called COVID 19, put forward the serious challenges for many countries all over the world and for Georgia among them. Almost the whole world is facing very serious obstacles on the international and national levels. Too many problems emerged in the world countries. To resist against the new disease has become the main priority for each country. The global processes caused by the pandemics have influenced the audit service as well. The uncertainty and unpredictability caused the new risks of deficiencies and activated already existed ones in the new environment. The situation became more complicated due to the fact that it can happen that the auditors do not consider the mentioned risks in the process of planning for audits or the risks may be considered mistakenly. The firms and other economical institutions in which the audit is carried out are obliged to adopt the new rules and changing environments in which their businesses function; they should change the rules of fulfilling the operation, preparing the financial accounts, the processes of their representing the information processes, safety of information shown in the financial accounts, the rules of their preparing; they also evaluate the possibilities of keeping on their activities in the nearest future. The qualified performing of the audit implies the basical elemenst which helps to create such environment where the possibility of the high level audit will be at the maximum. Implementing the quality control implies that such system will include two stages; each of them is directed towards providing the audit processes according the international standards There are several types of the quality improvement system. In all of them the main variable value represents the amount of costs for the proper system. All countries choose the system which provides benefits taking the costs into consideration. There are four main stages in the process of implementation the system which will ensure the high quality audit. Here are four main stages shown in the process of implementation:  The first stage: to carry out diagnostic observation;  The second stage: stating the view;  The third sage: working out the system;  The fourth stage: implementation of the system. The firms and other economical institutions where the audit is carried out are obliged to be reliable with their activities in the changing situation in which their businesses function. The subjects change the rules of carrying out the usual operations, change the open information given in the financial accounts, and estimate the possibilities of maintaining the existing possibilities for the nearest future. It is important to revise some standards out of Audit International Standards and to make them fit for revealing and assessing the risks of essential mistakes and discrepencies. The controlled variation of the standard regulates such issues as the newly corrected risks caused by influences of COVID-19 pandemic on the planned approaches to the audit and also, evaluation of the risks already defined and making changes in them taking into consideration the influence of the errors in the risk evaluations and influence made upon the planned evaluations and audits the changes of which will influence the evaluations of the risks in the inner control of the subject on the previously made imagination of the control environment, in order to define the measures to be taken in order to change the reactions to the mistakes using different measures in order to reach the trustful mechanisms to rely on. International standards of audit– answering to the assessed risks, the checked variation of the standard implies that it maybecome necessary to change the measures of reaction to the changes in the circumstances in order to obtain enough reliable measures and activities to control the situation by means of enough auditory evidences. The auditor has responsibilities to take into consideration that largening the deadlines will cause growth of the period and the risks of the dates of events which will happen in the time interval between accountability date and the date of the conclusion made by audit, the audit is also responsible for any event taking place later in relation to the Covid-19 situation. He is responsible also for evaluation of the fact about financial information. The enterprise functioning within nowadays complex environment taking into consideration the situation of COVID 19, should consider such priority issues as the uncertainty accompanying the Covid situation, related covenants, and others which accompany the pandemic period, among them the region, the financial state of customers and dealers, liquidating and paying capacity. During the process of the risk assessments it should considered that Covid 19 pandemic greatly influenced the global economics and the separate branches such as hotels business, retail sail, tourism and others. As a result of pandemic, it is possible that the number of audit considerations and thee circumstances can modify them which can be conditioned by different circumstances and the audit will state if there are incorrectable improper conditioned due to the circumstances. The audit will make it certain there are unimprovable mistakes which apart and together are essential for the financial accountability and the auditor will conclude that they cannot acquire the proper conditioned which apart or together could be essential financial accounts or the audit will conclude that they are not able to the essential accountability. Important researches were led to assess the appeared situation and it was concluded that the COVID 19 pandemic had influenced the financial situation which showed that the specific actions and procedures became complicated.


Author(s):  
N. Belala ◽  
D.E. Saїdouni ◽  
R. Boukharrou ◽  
A.C. Chaouche ◽  
A. Seraoui ◽  
...  

The design of real-time systems needs a high-level specification model supporting at the same time timing constraints and actions duration. The authors introduce in this paper an extension of Petri Nets called Time Petri Nets with Action Duration (DTPN) where time is associated with transitions. In DTPN, the firing of transitions is bound to a time interval and transitions represent actions which have explicit durations. The authors give an operational semantics for DTPN in terms of Durational Action Timed Automata (DATA). DTPN considers both timing constraints and durations under a true-concurrency semantics with an aim of better expressing concurrent and parallel behaviours of real-time systems.


Paleobiology ◽  
2016 ◽  
Vol 42 (3) ◽  
pp. 359-379 ◽  
Author(s):  
Mark E. Patzkowsky ◽  
Steven M. Holland

AbstractBiotic invasions in the fossil record provide natural experiments for testing hypotheses of niche stability, speciation, and the assembly and diversity of regional biotas. We compare ecological parameters (preferred environment, occupancy, median abundance, rank abundance) of genera shared between faunal provinces during the Richmondian Invasion in the Late Ordovician on the Laurentian continent. Genera that spread from one faunal province to the other during the invasion (invading shared genera) have high Spearman rank correlations (>0.5) in three of four ecological parameters, suggesting a high level of niche stability among invaders. Genera that existed in both regions prior to and following the invasion (noninvading shared genera) have low correlations (<0.3) and suggest niche shift between lineages that diverged at least 8 Myr earlier. Niche shift did not accumulate gradually over this time interval but appears to have occurred in a pulse associated with the onset of the Taconic orogeny and the switch from warm-water to cool-water carbonates in southern Laurentia.


Author(s):  
Andrey Morozov ◽  
Mihai A. Diaconeasa ◽  
Mikael Steurer

Abstract Advanced classical Probabilistic Risk Assessment (PRA) effectively combines various methods for quantitative risk evaluation, such as event trees, fault trees, and Bayesian networks. PRA methods and tools provide the means for the qualitative reliability evaluation (e.g., cut sets) and the computation of quantitative reliability metrics (e.g., end states probabilities). Modern safety-critical systems from various industrial domains tend toward a high level of autonomy and demand not only reliability but also resilience, the ability to recover from degraded or failed states. The numerical resilience analysis of such dynamic systems requires more flexible methods. These methods shall enable the analysis of the systems with sophisticated software parts and dynamic feedback loops. A suitable candidate is the Dual-graph Error Propagation Model (DEPM) that can capture nontrivial failure scenarios and dynamic fault-tolerance mechanisms. The DEPM exploits the method for the automatic generation of Markov chain models and the application of probabilistic model checking techniques. Moreover, the DEPM enables the analysis of highly-customizable system resilience metrics, e.g., “the probability of system recovery to a particular state after a specified system failure during a defined time interval.” In this paper, we show how DEPM-based resilience analysis can be integrated with the general PRA methodology for resilience evaluations. The proposed methodology is demonstrated on a safety-critical autonomous UAV system.


Zootaxa ◽  
2012 ◽  
Vol 3512 (1) ◽  
pp. 75 ◽  
Author(s):  
THOMAS SAUCÈDE ◽  
JEAN-CHRISTOPHE DUDICOURT ◽  
PHILIPPE COURVILLE

Two new echinoid genera and species, Salvaster roberti gen. et sp. nov. and Pygolampas edita gen. et sp. nov. are de-scribed. They were collected in the Calcaires à Spatangues Formation (CSF) that consists of limestone and clay sedimentsdeposited in the southeast of the Paris Basin (France) during the Early Hauterivian (Early Cretaceous). The CSF is datedfrom the Acanthodiscus radiatus chronozone, a time-interval of overall high sea level in Western Europe, but it yields arich shallow-water fossil fauna mostly represented by benthic invertebrates. Of the 54 echinoid species ever described inthe CSF, 26 species are recognized here. They are distributed into 16 different families, among which regular (13 species)and irregular (13 species) echinoids are represented in equal proportion. This work confirms the high level of echinoid diversity in the CSF for that time-period.


Most of the work on the effect of fertilization on the metabolism of seaurchin eggs has been concerned with the average rate of O 2 consumption before and after activation. Although observations of this type are of interest, the changes which take place during the actual fertilization of the eggs are more indicative of the mechanisms responsible for the initiation of development. Technical difficulties have impeded experiments of this latter type. Early workers (Warburg 1915) found it necessary to fertilize the eggs before the beginning of the experiment, or, after measuring the O 2 consumption of unfertilized eggs, to open the manometer vessels to effect insemination. The former method precludes any measurements during the fertilization reaction, and the latter involves a period of manipulation and consequent re-equilibration which exceeds the duration of the fertilization reaction. When, therefore, it is stated that the O 2 consumption rate increases upon fertilization or parthenogenetic activation by some 200-400%, what is usually implied is that the O 2 consumption rate measured over a considerable period of time after insemination is some 200-400% more than the rate for a similar period of time before insemination. Shearer (1922) was the first to realize the importance of measurements immediately after insemination; 1 min. After insemination he observed an increase in O 2 consumption which was not maintained at the original high level. We have been unable to confirm Shearer’s results when using a similar method (see fig. 2). In recent years further attempts have been made (e. g. Runnström 1933 b ; Brook, Druckrey and Herken 1938) to make measurements immediately after fertilization by having the sperm inside the manometer vessel before fertilization but separate from the eggs; at a given moment sperm and eggs are mixed; but in these condition, the shortest time interval measured after insemination was 10 min. (Runnström), by which time the initial phase of the fertilization reaction is over.


Perception ◽  
1988 ◽  
Vol 17 (6) ◽  
pp. 729-736 ◽  
Author(s):  
George Mather

In ‘Kanizsa’ figures, vivid subjective shapes are seen in the absence of explicit contours to define them. When two or more such figures are presented sequentially, so that the subjective shape occupies different positions, good apparent motion of the shape is usually reported. This motion percept must be mediated by a high-level process, in which form extraction precedes motion detection. Some spatial and temporal properties of this motion process are investigated. A major finding is that motion is only perceived when the time interval between successive frames falls below about 500 ms, and the duration of each frame exceeds about 80 ms.


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