The fusion power density produced in a tokamak is proportional to its magnetic field strength to the fourth power. Second-generation high temperature superconductor (2G HTS) wires demonstrate ...remarkable engineering current density (averaged over the full wire), JE, at very high magnetic fields, driving progress in fusion and other applications. The key challenge for HTS wires has been to offer an acceptable combination of high and consistent superconducting performance in high magnetic fields, high volume supply, and low price. Here we report a very high and reproducible JE in practical HTS wires based on a simple YBa2Cu3O7 (YBCO) superconductor formulation with Y2O3 nanoparticles, which have been delivered in just nine months to a commercial fusion customer in the largest-volume order the HTS industry has seen to date. We demonstrate a novel YBCO superconductor formulation without the c-axis correlated nano-columnar defects that are widely believed to be prerequisite for high in-field performance. The simplicity of this new formulation allows robust and scalable manufacturing, providing, for the first time, large volumes of consistently high performance wire, and the economies of scale necessary to lower HTS wire prices to a level acceptable for fusion and ultimately for the widespread commercial adoption of HTS.
The article atempts to retrace the establishment of the terrorist group “Islamic State” (IS, ISIS) by analyzing its structure, ideological and propaganda pratices, economic foundation and sources of ...recruitment.
The SuperOx and SuperOx Japan LLC companies were founded with the goal of developing a cost-effective technology for second generation HTS (2G HTS) tapes by utilizing a combination of the most ...advanced chemical and physical deposition techniques, together with implementing original tape architectures. In this paper we present a brief overview of our production and experimental facilities and recent results of 2G HTS tape fabrication, and describe the first tests of the tapes in model cables for AC and DC power application.
The article examines the history of the formation and reform of the system of state and municipal administration in Ukraine. In the conditions when the socio-political space of Ukraine is ...characterized by pronounced regionalism, and the issue of transition to a federal state system is excluded from the real political agenda, the nature of the development of the system of state and municipal administration can serve as a reflection of the ratio of centrifugal and centripetal trends in the internal political development of Ukraine. The article presents an analysis of the factors of internal political development of Ukraine that most influenced the formation of a centralized system of territorial administration in the country in the post- Soviet period and predetermined the weakness of local self-government, as well as the reasons for the failure of several attempts at reforms. Special attention is paid to the implementation of the decentralization policy after 2014. The article reveals the connection of the concept of modern administrative-territorial reform in Ukraine with the settlement process in the Donbas, as well as with the approaches in Western political science, according to which decentralization is considered as a tool for neutralizing the political potential of regionalism and countering regional separatism. The results and political orientation of decentralization in the context of the acute socio- economic crisis in Ukraine are evaluated.
The appearance in world politics of a dangerous phenomenon of the terrorist «Islamic state» was caused by a number of factors on global, regional and country levels. The worsening regional situation ...as a result of the overdue fundamental changes in turbulent development of the countries in the Middle East and North Africa is aggravated by an unlawful interference, dictated by the desire of some influential actors in the world politics to realize their geostrategic and geopolitical interests. As a result the international community has to confront a sharp rise of religious extremism that threatens to deepen a civilizational schism. Following steadfastenly a course on non-interference in the internal affairs of the countries in the region, Russia consistently appeals for the unification of the forces of the world community to address the new challenge to international stability and security.
To choose an optimal mathematical model and to practice the method of its use during finding the corpse under exposure of a direct solar radiation.
The studies were carried out on 9 corpses with body ...weight from 50 to 83 kg. The influence of black (6 corpses) and white (3 corpses) colored cotton fabrics was investigated to standardize a photoreceptive surface of clothes. In addition, the objects (bags made of substantial polyethylene, densely filled with moderately humid black soil) replacing corpses with mass of 5.5, 11.0, 16.5 and 22.0 kg, wrapped in cotton fabric of specified colors, that imitates clothes, were used. The objects' temperature was measured within the accuracy of 0.001 °C, air temperature - within accuracy of 0.1 °C. A simplified one-dimensional variant of the finite mathematical differences method, representing the process of corpse's cooling as a discrete transfer of heat from one layer (node) to another, was used in developing the mathematical modeling algorithm. The model consisted of ten nodes was used in calculations.
A mathematical model in the form of equations' system was developed, in which the variable reflecting the intensity of corpse's surface heating by sun rays was introduced. The example of calculation made with data of real measurements of corpse's temperature, that was in open place for the sun rays, is shown.
The results of numerical studies of an induction-melting furnace with a cone-shaped cold crucible for vitrification of high-level wastes with noble metals are presented. The study has been carried ...out using a 2D electrohydrodynamic two-frequency model taking into account the movement of noble-metal particles in a borosilicate-glass melt. Based on the mathematical modeling, a furnace with an induction-drain unit that ensures complete removal of noble metals together with the drained glass melt has been developed. The directions for further numerical and experimental studies are presented.
Much ink has been spilled in the last few decades on computer proofs, computer-assissted proofs, computer-verified proofs, etc. It is obvious that the advent and proliferation of computers have ...drastically changed the applications of mathematics. What is far less discussed, however, is how computers changed mathematics itself, as well as the stance of mathematicians in regard to mathematical reality, both as far as the possibilities to immediately observe it and the apprehension of what we can hope to prove. I am recounting my personal experience of using computers as a mathematical tool and the experience of similar use in the works of colleagues that I observed at close range. This experience has radically changed my perception of many aspects of mathematics; how it functions; and, especially, how it should be taught. This first introductory part consists mostly of reminiscences and some philosophical observations. Later parts describe several specific important advances in algebra and number theory that would had been impossible without computers.
In this part I pursue the discussion of the role of computers in additive number theroy. I sketch the definitive solution of the ternary = odd Goldbach conjecture, not in one of its 20th century ...asymptotric reformulations, but in its original 17th century form. Namely, that every odd number
n
> 5 is a sum
of three positive rational primes. This problem was only solved in 2013–2014 by Harald Helfgott, and there is no chance that it could have been obtained without the use of computers. Apart from that, I discuss the status of the binary = even Goldbach conjecture and partial results leading towards its solution, as well as some further related problems.
PDF
