3,085 research outputs found

    Dimension on Discrete Spaces

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    In this paper we develop some combinatorial models for continuous spaces. In this spirit we study the approximations of continuous spaces by graphs, molecular spaces and coordinate matrices. We define the dimension on a discrete space by means of axioms, and the axioms are based on an obvious geometrical background. This work presents some discrete models of n-dimensional Euclidean spaces, n-dimensional spheres, a torus and a projective plane. It explains how to construct new discrete spaces and describes in this connection several three-dimensional closed surfaces with some topological singularities It also analyzes the topology of (3+1)-spacetime. We are also discussing the question by R. Sorkin [19] about how to derive the system of simplicial complexes from a system of open covering of a topological space S.Comment: 16 pages, 8 figures, Latex. Figures are not included, available from the author upon request. Preprint SU-GP-93/1-1. To appear in "International Journal of Theoretical Physics

    Implementation of ICO European best practices by SMEs

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    The article deals with a new financial tool of attracting capital, known as Initial Coin Offering (ICO). In conditions of reduced banking lending and difficult access to finance for SMEs, ICO is viewed to be one of the possible ways to access capital. It considers the main advantages and disadvantages of ICO performance, including its typical features, challenges and regulatory approaches to tax regulation, cybersecurity. The authors of the article determine stages of the ICO mechanism, identifying potential risks and ways to mitigate them, focusing primarily on the need to control and regulate ICO projects. The authors identify the main types of ICO funding, including hybrid and pure funding. The research contains an analysis of ICO trends and their duration for the period of 2013-2017. The capital raised through ICO performance over the period of 2013-2017 is analysed, and determination of the exponential trend line showing the level of its approximation is determined. The study covers the territorial distribution of ICO, in which the top positions regarding the amount of capital raised by ICO are attributed to the USA and EU member states. The existence of ICO regulation in European countries, such as Switzerland and UK, was defined positive in terms of further development of the relevant regulation in the financial market. The article considers the best ICO practices in EU member states. To mitigate risks relating to ICO performance and to increase the level of investment, it would be reasonable to create regulatory rules in every country where cases of ICO performance are reported, based on the practice of the mentioned European countries. The authors give recommendations regarding ICO regulation in Ukraine, taking into consideration the relevant European experience

    Estimation of Reserves for Improving the Results of Patients with Multipresistant Pulmonary Tuberculosis in the Application of Surgical Methods Based on Analysis of the Efficiency of Conservative Treatment of a Specified Cohort

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    In order to improve the results of treatment of patients with multi-resistant pulmonary tuberculosis with the use of surgical methods, the effectiveness estimation of conservative treatment of 176 patients with this form of tuberculosis according to cohort analysis data in two districts of Kyiv were done.In the list were included following parameters: type of the tuberculosis, its clinical-radiological form and the prevalence of the process, the results of conservative treatment in patients who completely finished the course of anti-TB chemotherapy and the results of conservative treatment of 81 patients who had indications for surgical treatment but had not been operated. Processing of the materials of the study was carried out with the use of licensed software products included in the Microsoft Office Professional 2007 package. The predicted results of treatment were calculated on the condition of surgical intervention.Out of the total sample of patients, 31.3 % of the patients completed treatment. Mortality was 16.5 %, transferred to palliative care 11.9 %. More than one in three patients (35.2 %) stopped treatment at different times from the start.According to the clinic of thoracic surgery SU "National Institute of Phthisiology and Pulmonology named after F.G. Yanovsky NAMS of Ukraine ", the overall effectiveness of treatment for patients with limited multidrug-resistant tuberculosis with the use of surgical intervention is about 95 % in the absence of mortality. We have modelled the potential results of treatment of the selected cohort in case of the surgical stage is fully and timely applied in a complex of therapeutic treatment. If all 81 patients with indications for surgical treatment used that way, then, with the above efficiency, a complete cure could be predicted in 77 patients (44.5 % of the total number of observations), which in turn would allow predicting the achievement completion of treatment at 64.2 % with complete cure for 60.6 % of patients.Thus, it is established that the positive result of surgical treatment in the general complex of treatment measures in patients with multidrug-resistant pulmonary tuberculosis is able to improve the results of treatment of this contingent more than twice, reduce the mortality almost by three times, reduce the need for repeated courses of treatment from 7.4 % to 1.7 %, as well as to reduce the epidemiological reservoir of infection due to a significant decrease in the number of patients with failure to treat tuberculosis, interrupted and palliative treatment

    Effect of Added Nitrogen on Properties of SiCN Films Prepared by PECVD Using Hexamethyldisilazane

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    Silicon carbonitride thin films were obtained by plasma-enhanced chemical vapor deposition using native precursor hexamethyldisilazane with a nitrogen addition. Films were investigated by X-ray diffraction spectroscopy, Fourier transform infrared spectroscopy and nanoindentation. It is established that all the films were X-ray amorphous. An increase in nitrogen flow rate leads to increasing the number of Si-N bonds, which, in turn, promotes the rise of nanohardness and elastic modulus up to 20 GPa and 160 GPa, respectively. The optimum deposition parameters were established. The films can be recommended as hard coatings for strengthening cutting tools. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3532

    Soviet Illegal Whaling: The Devil and the Details

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    In 1948, the U.S.S.R. began a global campaign of illegal whaling that lasted for three decades and, together with the poorly managed “legal” whaling of other nations, seriously depleted whale populations. Although the general story of this whaling has been told and the catch record largely corrected for the Southern Hemisphere, major gaps remain in the North Pacific. Furthermore, little attention has been paid to the details of this system or its economic context. Using interviews with former Soviet whalers and biologists as well as previously unavailable reports and other material in Russian, our objective is to describe how the Soviet whaling industry was structured and how it worked, from the largest scale of state industrial planning down to the daily details of the ways in which whales were caught and processed, and how data sent to the Bureau of International Whaling Statistics were falsified. Soviet whaling began with the factory ship Aleut in 1933, but by 1963 the industry had a truly global reach, with seven factory fleets (some very large). Catches were driven by a state planning system that set annual production targets. The system gave bonuses and honors only when these were met or exceeded, and it frequently increased the following year’s targets to match the previous year’s production; scientific estimates of the sustainability of the resource were largely ignored. Inevitably, this system led to whale populations being rapidly reduced. Furthermore, productivity was measured in gross output (weights of whales caught), regardless of whether carcasses were sound or rotten, or whether much of the animal was unutilized. Whaling fleets employed numerous people, including women (in one case as the captain of a catcher boat). Because of relatively high salaries and the potential for bonuses, positions in the whaling industry were much sought-after. Catching and processing of whales was highly mechanized and became increasingly efficient as the industry gained more experience. In a single day, the largest factory ships could process up to 200 small sperm whales, Physeter macrocephalus; 100 humpback whales, Megaptera novaeangliae; or 30–35 pygmy blue whales, Balaenoptera musculus brevicauda. However, processing of many animals involved nothing more than stripping the carcass of blubber and then discarding the rest. Until 1952, the main product was whale oil; only later was baleen whale meat regularly utilized. Falsified data on catches were routinely submitted to the Bureau of International Whaling Statistics, but the true catch and biological data were preserved for research and administrative purposes. National inspectors were present at most times, but, with occasional exceptions, they worked primarily to assist fulfillment of plan targets and routinely ignored the illegal nature of many catches. In all, during 40 years of whaling in the Antarctic, the U.S.S.R. reported 185,778 whales taken but at least 338,336 were actually killed. Data for the North Pacific are currently incomplete, but from provisional data we estimate that at least 30,000 whales were killed illegally in this ocean. Overall, we judge that, worldwide, the U.S.S.R. killed approximately 180,000 whales illegally and caused a number of population crashes. Finally, we note that Soviet illegal catches continued after 1972 despite the presence of international observers on factory fleets

    Phase transformation B1 to B2 in TiC, TiN, ZrC and ZrN under pressure

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    Phase stability of various phases of MX (M = Ti, Zr; X = C, N) at equilibrium and under pressure is examined based on first-principles calculations of the electronic and phonon structures. The results reveal that all B1 (NaCl-type) MX structures undergo a phase transition to the B2-structures under high pressure in agreement with the previous total-energy calculations. The B1-MX structures are dynamically stable under very high pressure (210-570 GPa). The pressure-induced B2 (CsCl-type) MC phases are dynamically unstable even at high pressures, and TiN and ZrN are found to crystallize with the B2-structure only at pressures above 55 GPa. The first-order B1-to-B2 phase transition in these nitrides is not related to the softening of phonon modes, and the dynamical instability of B2-MX is associated with a high density of states at the Fermi level.Comment: 9 pages, 4 figure

    Ukrainian School оf Terminology

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    The main stages of establishment and origins of Ukrainian terminology school are analyzed beginning from the history of Ukrainian scientific terminology in correlation with the history of development of terminological activity in Ukraine, through formation of practical and theoretical foundations of Ukrainian terminology, development of theoretical and practical principles of Ukrainian terminology on the basis of russification of specialized terminologies and development of contemporary Ukrainian terminology following the formation of an independent Ukrainian state
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