20 research outputs found
Минимизация погрешности экспериментального определения переходных характеристик линейных аналоговых устройств с сосредоточенными параметрами
Розроблений та досліджений метод мінімізації похибки вимірювання перехідних характеристик лінійних аналогових пристроїв із зосередженими параметрами, обумовленої неідеальністю за формою реально сформованих ступінчастих випробувальних сигналів у наносекундному діапазоні тривалості. Мінімізація здійснюється шляхом корекції випробувальних сигналів за формою або врахуванні при вимірюваннях моделі неідеальності реально сформованих сигналів по системі “точкових” параметрів, які є зручними для безпосереднього експериментального визначення та введення по ним корекції.The determining error of finding transitional characteristics by the response of the direct method in the nanosecond range (for testing signals with edges 1-10 ns) is the error which is caused by the imperfection of real testing signal (TS) form. Imperfection is defined as the deviation of the real stepped TS from the ideal signal (a unit function). The method of the minimization of error of experimental determination of transitional characteristics, which is caused by the imperfection of real stepped TS form, is suggested and analyzed. Subject to this proviso, the estimate of the TS’ imperfection is proposed as the realization by the experimental determinated "point" parameters. For example such parameters may be the coordinates of the point of the spike maximum at the TS top, the settling time of the transitional process at the TS top with a specified error. The main points of the methods. With a prior information about that, the minimization of measuring error of nominal model' transitional characteristics is realized by the identification of the relation between real TS’ "point" parameters during forming of TS. Subject to this proviso, the spike at the TS’ top compensates the playback error of transitional characteristic (as the response) through the finite acceleration time. The method is considered as an example of imperfection stepped TS typical forms in the nanosecond range, which have a finite acceleration time, the spike and the oscillations at the top. The estimates of the effectiveness of minimizing the error compared to the error in determining the transitional characteristic, when the TS front is growing exponentially without the spike at the top, are obtained. The error can be minimized by experimental estimate of values real TS’ "point" parameters and introducing the correction to the calculation parameters result of the analytical model of the transitional characteristic. The method allows to measure the transitional characteristics based on their direct estimate by the response using real generated TS, which can be skewed in the nanosecond range, and to simplify the control.Разработан и исследован метод минимизации погрешности определения переходных характеристик линейных аналоговых устройств с сосредоточенными параметрами, обусловленной неидеальностью по форме реально сформированных ступенчатых испытательных сигналов в наносекундному диапазоне длительностей. Минимизация осуществляется путем коррекции испытательных сигналов по форме по системе “точечных” параметров, которые удобны для непосредственного экспериментального определения и введения по ним коррекции
Синтез экспоненциальных сплайнов на основе моделей линейных электрических цепей
Дано обґрунтування щодо застосування при визначенні параметрів лінійних електричних кіл і їх компонентів класу експоненціальних випробувальних сигналів (ВС) із метою отримання уніфікованого відгуку, форма якого є зручної до аналізу та контролю. Наведені основні визначення та методологія щодо синтезу експоненціальних сплайнів, що можуть бути безпосередньо сформовані у вигляді електричного сигналу у лінійних електричних колах.The grounds of application are given during measuring of parameters linear electric circuits and their components of class of exponential test signals in order to receive compatible response, the form which is comfortable for analysis and control. The main definitions and the synthesis of exponential splines methodology are given, which can be formulated as electric signal in linear electric circuits.Дано обоснование применения при измерениях параметров линейных электрических цепей и их компонентов класса экспоненциальных испытательных сигналов с целью получения унифицированного отклика, форма которого является удобной для анализа и контроля. Даны основные определения и методология синтеза экспоненциальных сплайнов, которые могут быть непосредственно сформированы в виде электрического сигнала в линейных электрических цепях
The MASTER-II network of robotic optical telescopes. First results
The main stages in the creation of the Russian segment of the MASTER network of robotic telescopes is described. This network is designed for studies of the prompt optical emission of gammaray bursts (GRBs; optical emission synchronous with the gamma-ray radiation) and surveys of the sky aimed at discovering uncataloged objects and photometric studies for various programs. The first results obtained by the network, during its construction and immediately after its completion in December 2010, are presented. Eighty-nine alert pointings at GRBs (in most cases, being the first ground telescopes to point at the GRBs) were made from September 2006 through July 2011. The MASTER network holds first place in the world in terms of the total number of first pointings, and currently more than half of first pointings at GRBs by ground telescopes are made by the MASTER network. Photometric light curves of GRB 091020, GRB 091127, GRB 100901A, GRB 100906A, GRB 10925A, GRB 110106A, GRB 110422A, and GRB 110530A are presented. It is especially important that prompt emission was observed for GRB 100901A and GRB 100906A, and thar GRB 091127, GRB 110422A, and GRB 110106A were observed from the first seconds in two polarizations. Very-wide-field cameras carried out synchronous observations of the prompt emission of GRB 081102, GRB 081130B, GRB 090305B, GRB 090320B, GRB 090328, and GRB 090424. Discoveries of Type Ia supernovae are ongoing (among them the brightest supernova in 2009): 2008gy, 2009nr, 2010V, and others. In all, photometry of 387 supernovae has been carried out, 43 of which were either discovered or first observed with MASTER telescopes; more than half of these are Type Ia supernovae. Photometric studies of the open clusters NGC 7129 and NGC 7142 have been conducted, leading to the discovery of 38 variable stars. Sixty-nine optical transients have been discovered. © 2013 Pleiades Publishing, Ltd
MASTER OT J004207.99+405501.1/M31LRN 2015 luminous red nova in M31: Discovery, light curve, hydrodynamics and evolution
We report the discovery and multicolour (VRIW) photometry of the rare explosive star MASTEROT J004207.99+405501.1 - a luminous red nova - in theAndromeda galaxy M31N2015-01a. We use our original light curve acquired with identical MASTER Global Robotic Net telescopes in one photometric system: VRI during the first 30 d and W (unfiltered) during 70 d. Also, we added published multicolour photometry data to estimate the mass and energy of the ejected shell and we discuss the likely formation scenarios of outbursts of this type. We propose an interpretation of the explosion that is consistent with an evolutionary scenario where the merging of stellar components or the disruption of the common envelope of a close binary can explain some luminous red novae. Radiative hydrodynamic simulations of a luminous red nova were carried out in extended parameter space to fit its light curves. We find that the multicolour passband light curves of the luminous red nova are consistent with an initial common envelope radius of 10 R⊙, a merger mass of 3M⊙ and an explosion energy of 3 × 1048 erg. As a result, the phenomenon of novae consists of two classes: classical nuclear novae and more rare events (red novae) connected with the loss of compact common envelopes. © 2017 The Authors. Published by Oxford University Press on behalf of the Royal Astronomical Society
"River Potudan" short story by A. Platonov and lost generation prose
В статье раскрывается типологическое сходство образа Никиты Фирсова и героев "потерянного поколения" зарубежной литературы. Прослеживается осмысление Платоновым феномена "потерянного поколения" и рассматриваются причины, по которым его интересовало это социокультурное явление. Дается краткий обзор зарубежной прозы "потерянного поколения". Автор выдвигает предположение о том, что топос войны и город на реке Потудани поляризуются как "мужской" и "женский", "непредсказумый" и "стабильный". Показывается, что неизбежность инициатического испытания героя заложена уже в самой ситуации пересечения границы двух миров. Отмечается, что трудности Никиты в общении с близкими людьми типичны для героев "потерянного поколения", вернувшихся домой. Намечаются возможности более глубокого рассмотрения диалектики социального и экзистенциального измерения в рассказах А. Платонова.The article reveals the typological similarity between Nikita Firsov and the "lost generation" characters in the foreign literature. Platonov's comprehension of the "lost generation" and the reasons for which he was interested in this sociocultural phenomenon are traced. A brief review of foreign prose of the "lost generation" is given. The author analyzes the polarizing of war space and the town on the Potudan′ river, like "masculine" and "feminine", "unpredictable" and "stable". The inevitability of the Nikita's initiative trial is already laid down in the situation of crossing the border of two worlds. Nikita's difficulties in communicating with folks are indicated like the typical feature of "lost generation" characters, who returned home. The opportunities for deeper consideration of the dialectics of the social and existential dimension in A. Platonov's novels are outlined
Metaphysics of sex and love in A. Platonovs’ prose (on the material of the short stories of 1930-1940s)
This research is devoted to metaphysics of sex and love in the A. Platonovs’ mature short stories in the context of philosophy of the first half of the XX century. This topic is actual, because the question of the spiritual origins of love feelings in the Platonovs’ world is not developed systematically enough. At the same time, it is one of the most important to understanding the originality of the creative individuality of A.Platonov. The author substantiates the importance of love in the world of the writer and offers the original typology of love feelings, based on the mature short stories of Platonov which were written in 1930-1940-s.Данная работа посвящена исследованию метафизики любви и пола в зрелых рассказах А. Платонова в контексте философской мысли первой половины XX века. Данная тема актуальна, поскольку вопрос о духовных истоках любовного чувства в платоновском мире разработан недостаточно системно. При этом он является одним из важнейших для понимания своеобразия творческой индивидуальности А. Платонова. Автор обосновывает значимость любви в художественном мире писателя и предлагает оригинальную типологию любовного чувства, опираясь на зрелые рассказы Платонова 1930-1940-х годов
Publisher: Institute for Animal Husbandry, Belgrade-Zemun UDC 636.087.7 EFFECT OF THE Spirulina platensis INCLUDED IN THE MAIN DIET ON THE BOAR SPERM QUALITY
Abstract: Microalgae Spirulina platensis accumulates many chemical components which are suitable for all higher organisms as food and forage raw material. There are a lot of vitally important for the organisms minerals and macroelements such as iron, calcium, sodium, potassium, copper, magnesium, phosphorus, selenium, vitamins, carotin, nucleic acids, enzymes and other active substances. That should explain the value of Spirulina as a feed additive for the agricultural animals. In the present work the influence of the microalgae Spirulina platensis on the quantitative and qualitative characteristics of boars ' sperm was studied. The experiment was carried out with 6 boars from Danube white breed in the experimental animal base of the Agricultural Institute- Shumen. The time of the experiment was divided in the control and experimental periods. During the control period the animals received the main diet in accordance with Bulgarian state standard BDS- 1642-96. In the experimental period to the main diet was added 7 ml / per head the fresh biomass of microalgae preserved by melasa (final quantity- 1,4 mg Spirulina platensis). The obtained results shown that the addition of Spirulina improves the sperm parameters in boars: the volume of the ejaculates increased with 30 ml in experimental period (306 ml against 276 in control, P<0,05) as well as the spermatozoa concentration enhanced with 27 mln/ml. The total dehydrogenases activities estimated by reaction with methylene blue as well as LDH activity were higher in the experimental period. Also the survivability of the spermatozoids at 24, 48 and 72 hour in the experimental period was more than in control
Immunoassay for troponin I using a glassy carbon electrode modified with a hybrid film consisting of graphene and multiwalled carbon nanotubes and decorated with platinum nanoparticles
This article describes a bioelectrode for the determination of human cardiac troponin-I (cTnI). A glassy carbon electrode was coated with a hybrid film of graphene and multiwalled carbon nanotube (G-MWCNT) and modified with platinum nanoparticles (Pt NPs) that were capped with mercaptopropionic acid. The PtNPs were anchored on the G-MWCNT hybrid film via the cross-linker 1-pyrenemethylamine and subsequently functionalized with antibody against troponin (anti-cTnI). The bioelectrode was characterized by transmission electron microscopy, scanning electron microscopy, cyclic voltammetry, and electrochemical impedance spectroscopy. The performance of the immunoelectrode was investigated by electrochemical impedance spectroscopy, and response was fit to Randle's equivalent circuit model. The charge transfer resistance (R-et) at a.c. frequencies of < 1 Hz is found to be a viable sensing parameter. The dissociation constant of the immunoreaction between surface immobilized anti-cTnI and the analyte cTnI is 0.29 nM (with a Hill coefficient of 0.23), this indicating a negative cooperativity and high binding affinity of cTnI for anti-cTnI on the electrode surface. The EIS response is linear in the 1.0 pg mL(-1) to 10 ng mL(-1) concentration range, and the R-et sensitivity is 145.5 a"broken vertical bar cm(2) per decade
Electrochemical Impedance Analysis of Biofunctionalized Conducting Polymer-Modified Graphene-CNTs Nanocomposite for Protein Detection
We report an electrodeposited poly(pyrrole-co-pyrrolepropylic acid) copolymer modified electroactive graphene-carbon nanotubes composite deposited on a glassy carbon electrode to detect the protein antigen (cTnI). The copolymer provides pendant carboxyl groups for the site-specific covalent immobilization of protein antibody, anti-troponin I. The hybrid nanocomposite was used as a transducer for biointerfacial impedance sensing for cTnI detection. The results show that the hybrid exhibits a pseudo capacitive behaviour with a maximum phase angle of 49 degrees near 1 Hz, which is due to the inhomogeneous and porous structure of the hybrid composition. The constant phase element of copolymer is 0.61 (n = 0.61), whereas, it is 0.88 (n = 0.88) for the hybrid composites, indicating a comparatively homogeneous microstructure after biomolecular functionalization. The transducer shows a linear change in charge transfer characteristic (R-et) on cTnI immunoreaction for spiked human serum in the concentration range of 1.0 pg mL(-1) - 10.0 ng mL(-1). The sensitivity of the transducer is 167.8 +/- 14.2 Omega cm(2) per decade, and it also exhibits high specificity and good reproducibility