357 research outputs found
Geo-simulation approach to modelling spatial objects and its application to creating thermokarst lake model using remote sensing data
Василь Стус і український окциденталізм. (Vasyl Stus and Ukrainian intellectual westernizer.)
Автор розглядає постать Василя Стуса в контексті європейських інтенцій української інтеліґенції. Західна орієнтація виразно засвідчена у творчості шістдесятників. Із трьох пластів європейської культури – класики, аванґарду та сучасного мистецтва (ґенерації гіпі) – молоді українські творці віддавали перевагу класичній спадщині. Цю парадигму переконливо втілив Василь Стус у своїй поетичній творчості, кореспондуючи з ідеями Ґете, Рільке, Камю тощо. Принциповий окциденталізм Стуса, хоча й був позицією самітника, вказував стратегію розвитку української культури та її виходу з-під колоніального впливу. (The author examines creative personality of Vasyl Stus in the context of European aspirations of the Ukrainian intellectual persons. Work of generation of 60th of ХХ century certainly testifies to their western orientation. From three layers of the European culture - the classics, advance-guard and contemporaneity - the young Ukrainian intellectual persons gave preference to classic heritage. This paradigm was convincingly incarnated by Stus in the poetry, which calls with the ideas of Goethe, Rilke, Camus of and other. Fundamental westernizer of Vasyl Sts, though was the special position, however specified strategy of development of the Ukrainian culture and her output from the colonial affected zone.
Negative parity states of B and C and the similarity with $^{12}C
The negative parity states of B and C were studied based on the
calculations of antisymmetrized molecular dynamics(AMD). The calculations well
reproduced the experimental strengths of Gamov-Teller(GT), and monopole
transitions. We, especially, focused on the and states, for
which GT transition strengths were recently measured. The weak and GT
transitions for the in B and C are described by a
well-developed cluster structure of + and +He,
respectively, while the strong transitions for the is characterized
by an intrinsic spin excitation with no cluster structure. It was found that
the state is a dilute cluster state, and its features are similar to
those of the C which is considered to be a gas state of three
clusters.Comment: 10 pages, 4 figures, submitterd to Physical Review
Effect of nuclear quadrupole interactions on the dynamics of two-level systems in glasses
The standard tunneling model describes quite satisfactorily the thermal
properties of amorphous solids at temperatures in terms of an ensemble
of two-level systems possessing logarithmically uniform distribution over their
tunneling amplitudes and uniform distribution over their asymmetry energies. In
particular, this distribution explains the observable logarithmic temperature
dependence of the dielectric constant. Yet, experiments have shown that at
ultralow temperatures such a temperature behavior breaks down and the
dielectric constant becomes temperature independent (plateau effect). In this
letter we suggest an explanation of this behavior exploiting the effect of the
nuclear quadrupole interaction on tunneling. We show that below a temperature
corresponding to the characteristic energy of the nuclear quadrupole
interaction the effective tunneling amplitude is reduced by a small overlap
factor of the nuclear quadrupole ground states in the left and right potential
wells of the tunneling system. It is just this reduction that explains the
plateau effect . We predict that the application of a sufficiently large
magnetic field should restore the logarithmic dependence because of the
suppression of the nuclear quadrupole interaction.Comment: To appear in the Physical Review Letter
МІНІМІЗАЦІЯ ВТРАТ В КАБЕЛЯХ ТРИФАЗНОЇ ЧОТИРЬОХПРОВІДНОЇ МЕРЕЖІ З ПАРАЛЕЛЬНИМИ АКТИВНИМИ ФІЛЬТРАМИ ЗА ДОПОМОГОЮ МИТТЄВОЇ КОМПЕНСАЦІЇ
Control strategy of shunt active filter based on forming the network current vector proportional to the instantaneous phase voltage vector with partial decrease of zero-sequence component that gives advantages of power losses in the four-wirecables is proposed. The optimal coefficient of decrease is determined by the ratio of specific active resistance values of the phase and neutral conductors, i.e. for each brand of four-wire power cable of three-phase network is its optimalcoefficient of decrease of zero-sequence component that provides a minimum of active power losses. Comparison of control strategies in value of instantaneous reactive power consumed by the three-phase source was performed. References 8, figures 5.Предложена стратегия управления параллельным активным фильтром, который базируется на формировании вектора тока источника пропорционального мгновенному вектору фазовой мощности с частичным ослабленим составляющей нулевой последовательности, дающей преимущества по величине мощности потерь в силовом четырёхпроводном кабеле в сравнении с известными стратегиями. Бібл. 9, рис. 4.Запропоновано стратегію керування паралельним активним фільтром, яка базується на формуванні вектора струму джерела пропорційним миттєвому вектору фазної напруги з частковим послабленням складової нульової послідовності, що дає переваги за величиною потужності втрат у силовому чотирьохпровідному кабелі в порівнянні з відомими стратегіями. Бібл. 9, рис. 4
Антенна решітка для радіомоніторингу
The radio control system based on the three elements antenna array with noise suppressionfunction is considered. Using of three elements allow to narrow the sector of space reviewing and to simplifythe block diagram. The proposed system provides suppression of the noise by means of simple technicalmeans including situation, when frequencies of the noise and useful signal coincideРассмотрена система радиоконтроля, в основу которой положена трехэлементная антенная решетка с функцией подавления помехи. Использование трех элементов позволяет сузить сектор обзора пространства и упростить блок-схему обработки сигнала. Предложенная система обеспечивает подавление помехи, в том числе совпадающей по частоте с полезным сигналом, при помощи простых технических средствРозглянуто систему радіоконтролю, що засновується на триелементній антенній решітці з функцією придушення завади. Використання трьох елементів дозволяє звузити сектор огляду простору та спростити блок-схему оброблення сигналу. Запропонована система забезпечує придушення завади, у тому числі співпадаючої за частотою з корисним сигналом, за допомогою простих технічних засобі
ФІЛЬТРАЦІЯ СТРУМІВ В ТРИФАЗНІЙ ТРИПРОВОДНІЙ СИСТЕМІ ЕЛЕКТРОЖИВЛЕННЯ ПРИ НЕСИМЕТРИЧНИХ СИНУСОЇДНИХ НАПРУГАХ
Purpose. Investigation of the optimal current distribution between source, shunt active filter and reactive compensator of a three-phase three-wire system that provides consumption of a sinusoidal symmetric current under asymmetric source voltages with minimal power losses was provided. Methodology. The tasks were solved by conducting theoretical and experimental studies. The main provisions of the theory of electrical circuits, the apparatus of mathematical analysis, methods for solving linear differential and algebraic equations, elements of matrix and complex calculus and vector algebra are used. During the development, modern methods and software of computer simulation of electrical engineering complexes and dynamic systems were applied: Matlab-Simulink, MATHCAD. Originality. The principle of compensating current distribution between PAF and reactive compensator of a three-phase three-wire power system with asymmetric sinusoidal voltage was proposed at which the input current is equal to the positive-sequence active current and rms value of PAF current is minimal. The feasibility to compensate the inactive sinusoidal Fryze current by reactive elements under arbitrary combination of load and source parameters was proved and expression for direct calculation of the reactive compensator parameters for generation of inactive Fryze current in the source unbalanced mode was obtained. Practical value. The simulative example for transmission line load showed that combined application of PAF and reactive compensator with the specified distribution of compensating currents ensured a reduction of power losses in 3.273 times and rms value of the SAF current is 12.9 % of rms value total compensation current.Розглянуто принципи активної фільтрації струму в трифазній трипровідній системі електроживлення при несиметричному синусоїдному джерелі живлення, що задовольняють вимогам стандарту IEEE Std.1459-2010. Показано переваги формування синусоїдного симетричного вхідного струму при паралельному підключенні активного фільтра та реактивного компенсатора. Доведено можливість компенсації неактивного синусоїдного струму Фрізе реактивними елементами при довільній комбінації параметрів лінійного навантаження та джерела. Отримана формула прямого розрахунку параметрів реактивного компенсатора для генерації неактивного струму Фрізе в несиметричному режимі трифазного джерела. Наводяться результати чисельного моделювання
The dynamic of secondary hemorrhagic progression of contusion in traumatic brain injury
Vyval M. B., Polishchuk M. E., Perekopaiko Y. M. The dynamic of secondary hemorrhagic progression of contusion in traumatic brain injury. Journal of Education, Health and Sport. 2017;7(1): 369-376. eISSN 2391-8306. DOI http://dx.doi.org/10.5281/zenodo.292929http://ojs.ukw.edu.pl/index.php/johs/article/view/4271 The journal has had 7 points in Ministry of Science and Higher Education parametric evaluation. Part B item 754 (09.12.2016).754 Journal of Education, Health and Sport eISSN 2391-8306 7© The Author (s) 2017;This article is published with open access at Licensee Open Journal Systems of Kazimierz Wielki University in Bydgoszcz, PolandOpen Access. This article is distributed under the terms of the Creative Commons Attribution Noncommercial License which permits any noncommercial use, distribution, and reproduction in any medium, provided the original author(s) and source are credited. This is an open access article licensed under the terms of the Creative Commons Attribution Non Commercial License(http://creativecommons.org/licenses/by-nc/4.0/) which permits unrestricted, non commercial use, distribution and reproduction in any medium, provided the work is properly cited.This is an open access article licensed under the terms of the Creative Commons Attribution Non Commercial License (http://creativecommons.org/licenses/by-nc/4.0/) which permits unrestricted, non commercial use, distribution and reproduction in any medium, provided the work is properly cited.The authors declare that there is no conflict of interests regarding the publication of this paper.Received: 02.01.2017. Revised 16.01.2017. Accepted: 24.01.2017. УДК 616.831-001.3-005.1 The dynamic of secondary hemorrhagic progression of contusion in traumatic brain injury M. B. Vyval, M. E. Polishchuk, Y. M. Perekopaiko Department of Neurosurgery, National Medical Academy of Postgraduate Education named after P.L. Shupik, Ministry of Health of Ukraine, Kyiv, UkraineTraumatology Department, Ternopil City Municipal Hospital of Emergency medicine , Ternopil, Ukraine AbstractIntroduction. Secondary posttraumatic changes in the brain often determine the clinical flow during traumatic brain injury (TBI). Prevention and early detection of secondary hemorrhagic progression (SHP) is very important for determination of the treatment strategy in patients with brain contusion.We studied the dynamic of brain contusion and its impact on the clinical course of brain injury. We found that the secondary hemorrhagic progression of contusion occurs in 43% and can be detected at the place of primary brain damage, and far away from it, and often can be seen in patients with a subdural hematoma. The larger contusion has the greater probability of progression and needs for surgical decompression. Progression is associated with the significant risk of clinical deterioration and mortality.Conclusions. Treatment tactics depends on severity of volumetric effect on the surrounding brain structures and manifestations of herniation syndrome. Key words: traumatic brain injury, brain contusion, secondary hemorrhagic progression of contusion
On the theory of resonant susceptibility of dielectric glasses in magnetic field
The anomalous magnetic field dependence of dielectric properties of
insulating glasses in the temperature interval is considered. In
this temperature range, the dielectric permittivity is defined by the resonant
contribution of tunneling systems. The external magnetic field regulates
nuclear spins of tunneling atoms. This regulation suppresses a nuclear
quadrupole interaction of these spins with lattice and, thus, affects the
dielectric response of tunneling systems. It is demonstrated that in the
absence of an external magnetic field the nuclear quadrupole interaction
results in the correction to the permittivity in the
temperature range of interest. An application of a magnetic field results in a
sharp increase of this correction approximately by a factor of two when the
Zeeman splitting approaches the order of . Further increase of the
magnetic field results in a relatively smooth decrease in the correction until
the Zeeman splitting approaches the temperature. This smooth dependence results
from tunneling accompanied by a change of the nuclear spin projection. As the
magnetic field surpasses the temperature, the correction vanishes. The results
obtained in this paper are compared with experiment. A new mechanism of the low
temperature nuclear spin-lattice relaxation in glasses is considered.Comment: 9 Pages, 5 Figures, To be submitted to the Physical Review B, please
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Mirror duality and noncommutative tori
In this paper, we study a mirror duality on a generalized complex torus and a
noncommutative complex torus. First, we derive a symplectic version of Riemann
condition using mirror duality on ordinary complex tori. Based on this we will
find a mirror correspondence on generalized complex tori and generalize the
mirror duality on complex tori to the case of noncommutative complex tori.Comment: 22pages, no figure
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