Logistic equation and COVID-19
The generalized logistic equation is used to interpret the COVID-19 epidemic data in several countries: Austria, Switzerland, the Netherlands, Italy, Turkey and South Korea. The model coefficients are calcu- lated: the growth rate and the expected number of infected people, as well as the exponent indexes in the generalized logistic equation. It is shown that the dependence of the number of the infected people on time is well described on average by the logistic curve (within the framework of a simple or general- ized logistic equation) with a determination coefficient exceeding 0.8. At the same time, the dependence of the number of the infected people per day on time has a very uneven character and can be described very roughly by the logistic curve. To describe it, it is necessary to take into account the dependence of the model coefficients on time or on the total number of cases. Variations, for example, of the growth rate can reach 60%. The variability spectra of the coefficients have characteristic peaks at periods of sev- eral days, which corresponds to the observed serial intervals. The use of the stochastic logistic equation is proposed to estimate the number of probable peaks in the coronavirus incidence.
The article deals with a model of the dynamics of aggregate banking assets to GDP in the Eurasian Economic Union member states based on the logistic equation. A fuzzy Mamdani model is applied to measure the extent to which this dynamics has an effect on Capital Adequacy Ration as a regulatory standard. Based on this model we consider scenarios of transition to regulatory standards recommended by the Basel Committee on Banking Supervision in the framework of Basel III transformation.
The global economy passes the COVID-19 related crises. For various projections, the output fall in Russia in 2020 will vary from 2 to 8 percent. So, in comparison with the crises of 1998 and 2008, the current shock can be more severe. In the upcoming years the Russian economy will pass the recovery stage, approaching the new balanced growth path. What proximate sources would push this growth?
With the neoclassical industry growth accounting and the Russia KLEMS dataset the present report aims to shed light on this, considering the growth patterns and sources of growth after the crises of 1998 and 2008. The report unveils the most important sources of the after-2008 stagnation in Russia, which are the decreasing efficiency of the extended oil and gas sector and the suspension of technology convergence. Since the recovery in Russia will be, most probably, caused by the increasing demand on energy and raw materials, driven by the recovery of global markets, policy implications for Russia should include efforts to improve efficiency in such export-oriented sectors, as oil and gas, and efforts, which aim to boost technology convergence such as backing export-oriented firms, which have been integrated to global value chains.
This work contains an express answer to four questions about what happened in the higher education system at the very beginning of the introduction of quarantine measures: (1) how have universities and the states reacted worldwide? (2) what are the reaction of Russian universities? (3) how do students and teachers perceive the situation? (4) Is there enough infrastructure to implement quarantine measures of remote work and training?
Most of the analytics were collected on an initiative basis, but the most important sections were written on the basis of data collected within the working group of the Russian Ministry of Education and Science to organize educational activities in the context of preventing the spread of COVID-19 infection in the Russian Federation under the leadership of the Department of Youth Policy (in terms of sociological student survey) and the Department of Information Technology in the field of science and higher education (in terms of monitoring infrastructure and opportunities Translation courses in distance learning). Data collection and analysis would not have been possible without cooperation with MIREA, as well as representatives of ITMO University, Ural Federal University, Tomsk State University and support from Mail.ru Group and the Association of Volunteer Centers.
Debt, as one of basic human relations, has profound effects on economic growth. Debt accumulation in the global economy was modeled by the stochastic logistic equation reflecting causality between leverage and its relative rate of change. The model, identifying interactions and feedbacks in aggregate behaviour of creditors and borrowers, addressed various issues of macrofinancial stability. Qualitatively diverse patterns, including the Wicksellian (normal) market, the Minsky financial bubbles and the Fisherian debt-deflation, were discerned by appropriate combinations of rates of return, spreads and leverage. The Kolmogorov-Fokker-Plank equation was used to find out the stationary gamma distribution of leverage that was instrumental for the evaluation of appropriate failure and survival functions. Two patterns corresponding to different forms of a stationary gamma distribution were recognized in the long run leverage dynamics and were simulated as scenarios of a possible system evolution. In particular, empirically parameterized asymptotical distribution indicated excessive leverage and unsustainable global debt accumulation. It underlined the necessity of comprehensive reforms aiming to decrease uncertainty, debt and leverage. Assuming these reforms were successfully implemented, global leverage distributions would have converged in the long run to a peaked gamma distribution with the mode identical to the anchor leverage. The latter corresponded to a balanced long run debt demand and supply, hence to fairly evaluated financial assets fully collateralized by real resources. A particular case of macrofinancial Tobin’s q-coefficients following the Ornstein-Ulenbeck process was studied to evaluate a reasonable range of squeezing the bloated world finance. The model was verified on data published by the IMF in Global Financial Stability Reports for the period 2003-2013.
In the article, the authors analyze the nature of the genesis and features of the spread of false information under the coronavirus infection COVID-19’s outbreak. An original classification of fakes distributed during the period of infodemia with an attempt to identify beneficiaries of media activity, indicators of fake information, as well as the summary of the most famous models for the spread of fake information on social networks, is given
Cities possess massive resources, talent and creativity and serve as hubs for knowledge sharing, experimentation and innovation, generating new ideas, embedding these solutions locally and scaling-up successful practices. Cities, however, are not abstract sustainability-making machines; they are places where real people live, work, study and flourish. Cities are made of people, by people and for people. Sustainable measures will have to make sense to inhabitants of cities, making their life more liveable. Furthermore, it is people who drive sustainability and who are its ultimate source and beneficiaries. This vision underpins the notion of people-smart sustainable cities, introduced in this publication.
The Arctic Council is well-positioned to play a leadership role in better understanding the impact of Covid-19 in the Arctic and spearheading activities to respond to the pandemic in the short-, medium- and longer-term. This briefing document was prepared to inform initial discussions regarding the coronavirus pandemic in the Arctic at the Senior Arctic Officials’ executive meeting (SAOX) on 24-25 June 2020. It draws together available information – to date (June 2020) – about the impact of Covid-19 in the Arctic: Briefing Document for SAOs June 2020 For public release Page 10 of 83 Covid-19 and the actions taken to respond in the Arctic region. The document draws from a wide spectrum of sources, reflecting the complex and intricate nature of how Covid-19 affects Arctic peoples and communities, including national and subnational statistical databases and tools, peer-reviewed articles, policy statements, technical guidelines, field surveys, and local observations from Arctic communities.
The coronavirus pandemic (SARS-CoV-2 or COVID-19, 2019nCoV), which, according to the Chinese office of the World Health Organization (WHO), began to spread from Wuhan no later than December 2019, now has secured its place among global security challenges. Scientists are trying to develop a vaccine against the 2019-nCoV virus, and WHO is helping them. According to the Nature magazine, in April 2020, more than 90 vaccines against SARS-CoV-2 were in the development of a number of pharmaceutical companies (for example, Moderna, Pfizer, Johnson & Johnson, GlaxoSmithKline) and research groups at universities around the world. Researchers tested various technologies, some of which had not previously been used in licensed vaccines. In this paper, we will try to outline some trends in the fight against the pandemic within the countries of the Iberian Peninsula, special attention will be paid to information coverage of this process and misinformation (fake news phenomenon)
On April 21, 2020, the Presidium of the Supreme Court of the Russian Federation issued an “Overview of selected issues of judicial practice, related to the application of legislation and measures to stop the spread of the coronavirus infection (COVID-19) on the territory of the Russian Federation No. 1” (the “Overview”).
This Overview sets out a number of important clarifications on the practical application of recent legislative developments as well as recent COVID-19 related measures to dispute resolution, contract performance, creditors’ rights, the imposition of criminal liability for spreading fake news on COVID-19 and on administrative liability for the violation of sanitary rules and protective measures. We set forth herein a number of clarifications affecting contract performance and dispute resolution.
A model for organizing cargo transportation between two node stations connected by a railway line which contains a certain number of intermediate stations is considered. The movement of cargo is in one direction. Such a situation may occur, for example, if one of the node stations is located in a region which produce raw material for manufacturing industry located in another region, and there is another node station. The organization of freight traﬃc is performed by means of a number of technologies. These technologies determine the rules for taking on cargo at the initial node station, the rules of interaction between neighboring stations, as well as the rule of distribution of cargo to the ﬁnal node stations. The process of cargo transportation is followed by the set rule of control. For such a model, one must determine possible modes of cargo transportation and describe their properties. This model is described by a ﬁnite-dimensional system of diﬀerential equations with nonlocal linear restrictions. The class of the solution satisfying nonlocal linear restrictions is extremely narrow. It results in the need for the “correct” extension of solutions of a system of diﬀerential equations to a class of quasi-solutions having the distinctive feature of gaps in a countable number of points. It was possible numerically using the Runge–Kutta method of the fourth order to build these quasi-solutions and determine their rate of growth. Let us note that in the technical plan the main complexity consisted in obtaining quasi-solutions satisfying the nonlocal linear restrictions. Furthermore, we investigated the dependence of quasi-solutions and, in particular, sizes of gaps (jumps) of solutions on a number of parameters of the model characterizing a rule of control, technologies for transportation of cargo and intensity of giving of cargo on a node station.
Let k be a field of characteristic zero, let G be a connected reductive algebraic group over k and let g be its Lie algebra. Let k(G), respectively, k(g), be the field of k- rational functions on G, respectively, g. The conjugation action of G on itself induces the adjoint action of G on g. We investigate the question whether or not the field extensions k(G)/k(G)^G and k(g)/k(g)^G are purely transcendental. We show that the answer is the same for k(G)/k(G)^G and k(g)/k(g)^G, and reduce the problem to the case where G is simple. For simple groups we show that the answer is positive if G is split of type A_n or C_n, and negative for groups of other types, except possibly G_2. A key ingredient in the proof of the negative result is a recent formula for the unramified Brauer group of a homogeneous space with connected stabilizers. As a byproduct of our investigation we give an affirmative answer to a question of Grothendieck about the existence of a rational section of the categorical quotient morphism for the conjugating action of G on itself.
Let G be a connected semisimple algebraic group over an algebraically closed field k. In 1965 Steinberg proved that if G is simply connected, then in G there exists a closed irreducible cross-section of the set of closures of regular conjugacy classes. We prove that in arbitrary G such a cross-section exists if and only if the universal covering isogeny Ĝ → G is bijective; this answers Grothendieck's question cited in the epigraph. In particular, for char k = 0, the converse to Steinberg's theorem holds. The existence of a cross-section in G implies, at least for char k = 0, that the algebra k[G]G of class functions on G is generated by rk G elements. We describe, for arbitrary G, a minimal generating set of k[G]G and that of the representation ring of G and answer two Grothendieck's questions on constructing generating sets of k[G]G. We prove the existence of a rational (i.e., local) section of the quotient morphism for arbitrary G and the existence of a rational cross-section in G (for char k = 0, this has been proved earlier); this answers the other question cited in the epigraph. We also prove that the existence of a rational section is equivalent to the existence of a rational W-equivariant map T- - - >G/T where T is a maximal torus of G and W the Weyl group.