121 research outputs found
Using the Scale Software for Critical Analysis
This article shows the experience of using the SCALE software package (hereinafter SCALE) to analyze the criticality of critical benchmark experiments. This experience was obtained during the familiarization of SCALE for research purposes on the basis of the Department of Nuclear Physics and Technologies (DNPaT) of the IATE MEPhI. Test calculations of the effective multiplication factor ( ) critical assemblies with different parameters was produced, research different method of calculate multigroup constants
Features of Formation of the Cyclone Wakes (Fluctuations in Seawater Temperature) in the Area of Cape Svobodny, the Southeastern Part of the Sakhalin Island
Purpose. The purpose of this work is to study the particulars of the formation of cyclone wakes after the regular passage of cyclones over the area of the wave measurements, and to estimate the internal wave parameters along the track according to the field observations.
Methods and Results. The analysis of data from the field observations of sea waves and water temperature is presented. The measurements were carried out by a ARW-K14 device (autonomous recorder of the waves and water temperature) in the area of the Cape Svobodny on the southeastern coast of the Sakhalin Island at a depth about 8 m. The recorded time series of the sea level and temperature fluctuations, lasting about one and a half months, were subjected to spectral analysis using specialized Kyma spectral analysis software. Dominant temperature fluctuations reaching 8.5 °C with a 13.1 h period were detected in the upper mixed layer of the ocean. These fluctuations were identified as the cyclone wakes in the stage of their relaxation. Taking into account the synoptic circumstances that existed during the passage of several cyclones and the associated storms in the observation area, the authors investigated the presence or absence of a trace.
Conclusions. It is shown that if the next storm arrives earlier than 10 days after the previous one, the trace may be shorter or even absent due to active water mixing in the upper mixed layer of the ocean. For the data obtained, the value of the coefficient ∈ in the expression ω = (1 + ∈ ) f, which connects the dominant frequency ω of internal waves, i.e. almost inertial oscillations in the trace of each typhoon, with the inertial frequency f (the Coriolis parameter determined by the geographical latitude of the water area where the waves propagate), is close to the value proposed in the paper by E. Kunze. Using a formula due to J. F. Price, the characteristic horizontal lengths of internal waves in the direction of movement inside the wakes of cyclones moving at a speed 15–35 knots are determined. These lengths range from 304.6 to 1066.1 km
Time-optimal algorithms focused on the search for random pulsed-point sources
The article describes methods and algorithms related to the analysis of dynamically changing discrete random fields. Time-optimal strategies for the localization of pulsed-point sources having a random spatial distribution and indicating themselves by generating instant delta pulses at random times are proposed. An optimal strategy is a procedure that has a minimum (statistically) average localization time. The search is performed in accordance with the requirements for localization accuracy and is carried out by a system with one or several receiving devices. Along with the predetermined accuracy of localization of a random pulsed-point source, a significant complicating factor of the formulated problem is that the choice of the optimal search procedure is not limited to one-step algorithms that end at the moment of first pulse generation. Moreover, the article shows that even with relatively low requirements for localization accuracy, the time-optimal procedure consists of several steps, and the transition from one step to another occurs at the time of registration of the next pulse by the receiving system. In this case, the situation is acceptable when during the process of optimal search some of the generated pulses are not fixed by the receiving system. The parameters of the optimal search depending on the number of receiving devices and the required accuracy of localization are calculated and described in the paper.This work was supported in part by the Russian Foundation for Basic Research (projects no 18-51-00001 and 19-01-00128), and Ministry of Science and Higher Education of the Russian Federation (project no. № AAA-A17-117052410034-6)
Healthy ageing and regional health care system of the Great Patriotic War veterans
The term of "Healthy Ageing" is about creating the environments and opportunities that enable people to be and to do what they value throughout their lives. Healthy ageing require multipurpose policy framework with biological, social, economic, cultural and ecological aspects. The long-term experience of Saratov Regional Hospital for War Veterans in development and management of competencies required for healthy ageing programs is generalized in the article. Science evidence base of healthy ageing was formulated including results of the original studies with veterans of Great Patriotic War involved.</p
Magnetothemopower study of quasi two-dimensional organic conductor -(BEDT-TTF)KHg(SCN)
We have used a low-frequency magneto-thermopower (MTEP) method to probe the
high magnetic field ground state behavior of
-(BEDT-TTF)KHg(SCN) along all three principal crystallographic
axes at low temperatures. The thermopower tensor coefficients (
and ) have been measured to 30 T, beyond the anomalous low temperature,
field-induced transition at 22.5 T. We find a significant anisotropy in the
MTEP signal, and also observe large quantum oscillations associated with the de
Haas - van Alphen effect. The anisotropy indicates that the ground state
properties are clearly driven by mechanisms that occur along specific
directions for the in-plane electronic structure. Both transverse and
longitudinal magnetothermopower show asymptotic behavior in field, which can be
explained in terms of magnetic breakdown of compensated closed orbits.Comment: 9 pages, 10 figure
Measurements of spin rotation parameter A in pion-proton elastic scattering at 1.62 GeV/c
The ITEP-PNPI collaboration presents the results of the measurements of the
spin rotation parameter A in the elastic scattering of positive and negative
pions on protons at P_beam = 1.62 GeV/c. The setup included a
longitudinally-polarized proton target with superconductive magnet, multiwire
spark chambers and a carbon polarimeter with thick filter. Results are compared
to the predictions of partial wave analyses. The experiment was performed at
the ITEP proton synchrotron, Moscow.Comment: 7 pages, 3 figures. To be published in Phys. Lett.
Dispenser for water sampling from supercritical convection loop
Since 2009, the Kharkov Institute of Physics and Technology is working towards the development of equipment
and methods for testing the materials for reactors SCWR (STCU project P4841). Supercritical water convection loop
with a vessel, which is exposed to electron irradiation of the electron accelerator LU-10 (8…10 MeV, 10 kW), provides
an opportunity to study corrosion and mechanical damage of sample materials. Small quantity water sample
(1…3 ml) dispenser is designed for sampling the water out of the loop which is under 23.5 MPa pressure.С 2009 года в Харьковском физико-техническом институте ведутся работы, направленные на разработку оборудования и методологии для оценки реакторных материалов, предназначенных для реакторов SCWR (проект УНТЦ P4841). Специально разработана в ХФТИ сверхкритическая водяная конвекционная петля с камерой для облучения ускорителем электронов ЛУ-10 (8…10 МэВ, до 10 кВт) дает возможность изучения коррозии и механических повреждений материалов при облучении пучком электронов. Разработан дискретный дозатор для отбора проб воды (1…3 мл) из системы, находящейся под давлением 23,5 МПа.З 2009 року в Харківському фізико-технічному інституті ведуться роботи, що спрямовані на розробку устаткування та методології для оцінки реакторних матеріалів, призначених для реакторів SCWR (проект УНТЦ P4841). Спеціально розроблена в ХФТІ суперкритична водяна конвекційна петля з камерою для опромінення прискорювачем електронів ЛУ-10 (8…10 МеВ, до 10 кВт) дає можливість вивчення корозії і механічних пошкоджень матеріалів при опроміненні пучком електронів. Розроблено дискретний дозатор для відбору проб води (1…3 мл) з системи, яка знаходиться під тиском 23,5 МП
Membranes with a boundary
We investigate the recently developed theory of multiple membranes. In
particular, we consider open membranes, i.e. the theory defined on a membrane
world volume with a boundary. We first restrict our attention to the gauge
sector of the theory. We obtain a boundary action from the Chern-Simons terms.
Secondly, we consider the addition of certain boundary terms to various
Chern-Simons theories coupled to matter. These terms ensure the full bulk plus
boundary action has the correct amount of supersymmetry. For the ABJM model,
this construction motivates the inclusion of a boundary quartic scalar
potential. The boundary dynamics obtained from our modified theory produce
Basu-Harvey type equations describing membranes ending on a fivebrane. The
ultimate goal of this work is to throw light on the theory of fivebranes using
the theory of open membranes.Comment: 48 pages, Latex, v2 references adde
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