250 research outputs found
Preliminary results of investigation of solid interplanetary matter in the vicinity of the moon
Density of matter near moon found to be greater than that of interplanetary spac
Energy risk management in urban projects management
global and significantly affect (negatively, positively) the state and development of the national and world economy. The purpose of the paper is the formation of methodical-practical foundations of energy risk management in the energy sector.METHODS: The matrix method was used in building the energy security risk assessment matrix. Economic-mathematical modeling was used. Depending on the characteristics of the dynamic series and the available information, the methods of analytical alignment, smoothing using the moving average, the average absolute increase, and the average coefficient of change were applied.FINDINGS: The energy security risk assessment matrix was created. The development of a strategy for the behavior of subjects of market relations in the electricity market should be based not only on the results of risk identification and assessment and the developed risk management plan, but also on the risk response plan and the method of their control (monitoring). The coefficient of use of the installed energy capacity was in the range of 32–26% in Poland in 2021. Calculations of average annual growth rates for each of the dynamic series give reason to state that the highest growth rates of dependence on energy imports were characteristic of coal (+4.17%) and the lowest ones — of oil (+0.35%) during 1990–2021. Considering the forecast values for 2030, a certain decrease in the growth rate of dependence on the import of energy resources (for coal and oil) and an increase- for gas are expected.CONCLUSION: As a conclusion, the method of forecasting the total final energy consumption of the country was improved for forecasting the amount of energy resources in order to use it for building an energy policy that considers such variables as the economic situation and the political situation in the country. The formation of a risk response plan should be based on management plans and documentation of risk manifestations, intellectual and organizational assets of the economic entity (generalized risk management experience, management strategies, templates, etc.). manifestations, intellectual and organizational assets of the economic entity (generalized risk management experience, management strategies, templates, etc.)
Evaluation as a tool for quality management of inclusive processes in education
The article suggests a number of systematized criteria which can be used when evaluating the effects of inclusive processes in education institutions. Evaluation is considered as a set of measures to prepare and conduct a systematic study of the activities of an education institution in order to obtain reliable information about the state and prospects for the development of inclusive processes, to obtain data for predicting the further development of the inclusive educational process and to achieve the planned results of the implementation of inclusion by the education institution.В статье рассматривается ряд критериев, которые целесообразно использовать при эвалюации эффектов инклюзивных процессов в образовательных организациях
Representation theory of some infinite-dimensional algebras arising in continuously controlled algebra and topology
In this paper we determine the representation type of some algebras of
infinite matrices continuously controlled at infinity by a compact metrizable
space. We explicitly classify their finitely presented modules in the finite
and tame cases. The algebra of row-column-finite (or locally finite) matrices
over an arbitrary field is one of the algebras considered in this paper, its
representation type is shown to be finite.Comment: 33 page
Coherent spin relaxation in molecular magnets
Numerical modelling of coherent spin relaxation in nanomagnets, formed by
magnetic molecules of high spins, is accomplished. Such a coherent spin
dynamics can be realized in the presence of a resonant electric circuit coupled
to the magnet. Computer simulations for a system of a large number of
interacting spins is an efficient tool for studying the microscopic properties
of such systems. Coherent spin relaxation is an ultrafast process, with the
relaxation time that can be an order shorter than the transverse spin dephasing
time. The influence of different system parameters on the relaxation process is
analysed. The role of the sample geometry on the spin relaxation is
investigated.Comment: Latex file, 22 pages, 7 figure
Paleo-Ecology of the Yedoma Ice Complex on Sobo-Sise Island (EasternLena Delta, Siberian Arctic)
Late Pleistocene permafrost of the Yedoma type constitutes a valuable paleo-environmental archive due to the presence of numerous and well-preserved floral and faunal fossils. The study of the fossil Yedoma inventory allows for qualitative and quantitative reconstructions of past ecosystem and climate conditions and variations over time. Here, we present the results of combined paleo-proxy studies including pollen, chironomid, diatom and mammal fossil analyses from a prominent Yedoma cliff on Sobo-Sise Island in the eastern Lena Delta, NE Siberia to complement previous and ongoing paleo-ecological research in western Beringia. The Yedoma Ice Complex (IC) cliff on Sobo-Sise Island (up to 28 m high, 1.7 km long) was continuously sampled at 0.5 m resolution. The entire sequence covers the last about 52 cal kyr BP, but is not continuous as it shows substantial hiatuses at 36–29 cal kyr BP, at 20–17 cal kyr BP and at 15–7 cal kyr BP. The Marine Isotope Stage (MIS) 3 Yedoma IC (52–28 cal kyr BP) pollen spectra show typical features of tundra–steppe vegetation. Green algae remains indicate freshwater conditions. The chironomid assemblages vary considerably in abundance and diversity. Chironomid-based TJuly reconstructions during MIS 3 reveal warmer-than-today TJuly at about 51 cal kyr BP, 46-44 and 41 cal kyr BP. The MIS 2 Yedoma IC (28–15 cal kyr BP) pollen spectra represent tundra-steppe vegetation as during MIS 3, but higher abundance of Artemisia and lower abundances of algae remains indicate drier summer conditions. The chironomid records are poor. The MIS 1 (7–0 cal kyr BP) pollen spectra indicate shrub-tundra vegetation. The chironomid fauna is sparse and not diverse. The chironomid-based TJuly reconstruction supports similar-as-today temperatures at 6.4–4.4 cal kyr BP. Diatoms were recorded only after about 6.4 cal kyr BP. The Sobo-Sise Yedoma record preserves traces of the West Beringian tundra-steppe that maintained the Mammoth fauna including rare evidence for woolly rhinoceros’ presence. Chironomid-based TJuly reconstructions complement previous plant-macrofossil based TJuly of regional MIS 3 records. Our study from the eastern Lena Delta fits into and extends previous paleo-ecological Yedoma studies to characterize Beringian paleo-environments in the Laptev Sea coastal region
Characterization of the absolute frequency stability of an individual reference cavity
We demonstrated for the first time the characterization of absolute frequency
stability of three reference cavities by cross beating three laser beams which
are independently locked to these reference cavities. This method shows the
individual feature of each reference cavity, while conventional beatnote
measurement between two cavities can only provide an upper bound. This method
allows for numerous applications such as optimizing the performance of the
reference cavity for optical clockwork.Comment: 3 figures, 9 page
A high stability semiconductor laser system for a Sr-based optical lattice clock
We describe a frequency stabilized diode laser at 698 nm used for high
resolution spectroscopy of the 1S0-3P0 strontium clock transition. For the
laser stabilization we use state-of-the-art symmetrically suspended optical
cavities optimized for very low thermal noise at room temperature. Two-stage
frequency stabilization to high finesse optical cavities results in measured
laser frequency noise about a factor of three above the cavity thermal noise
between 2 Hz and 11 Hz. With this system, we demonstrate high resolution remote
spectroscopy on the 88Sr clock transition by transferring the laser output over
a phase-noise-compensated 200 m-long fiber link between two separated
laboratories. Our dedicated fiber link ensures a transfer of the optical
carrier with frequency stability of 7 \cdot 10^{-18} after 100 s integration
time, which could enable the observation of the strontium clock transition with
an atomic Q of 10^{14}. Furthermore, with an eye towards the development of
transportable optical clocks, we investigate how the complete laser system
(laser+optics+cavity) can be influenced by environmental disturbances in terms
of both short- and long-term frequency stability.Comment: 9 pages, 9 figures, submitted to Appl. Phys.
Paleo-Ecology of the Yedoma Ice Complex on Sobo-Sise Island (Eastern Lena Delta, Siberian Arctic)
Late Pleistocene permafrost of the Yedoma type constitutes a valuable paleo-environmental archive due to the presence of numerous and well-preserved floral and faunal fossils. The study of the fossil Yedoma inventory allows for qualitative and quantitative reconstructions of past ecosystem and climate conditions and variations over time. Here, we present the results of combined paleo-proxy studies including pollen, chironomid, diatom and mammal fossil analyses from a prominent Yedoma cliff on Sobo-Sise Island in the eastern Lena Delta, NE Siberia to complement previous and ongoing paleo-ecological research in western Beringia. The Yedoma Ice Complex (IC) cliff on Sobo-Sise Island (up to 28 m high, 1.7 km long) was continuously sampled at 0.5 m resolution. The entire sequence covers the last about 52 cal kyr BP, but is not continuous as it shows substantial hiatuses at 36–29 cal kyr BP, at 20–17 cal kyr BP and at 15–7 cal kyr BP. The Marine Isotope Stage (MIS) 3 Yedoma IC (52–28 cal kyr BP) pollen spectra show typical features of tundra–steppe vegetation. Green algae remains indicate freshwater conditions. The chironomid assemblages vary considerably in abundance and diversity. Chironomid-based TJuly reconstructions during MIS 3 reveal warmer-than-today TJuly at about 51 cal kyr BP, 46-44 and 41 cal kyr BP. The MIS 2 Yedoma IC (28–15 cal kyr BP) pollen spectra represent tundra-steppe vegetation as during MIS 3, but higher abundance of Artemisia and lower abundances of algae remains indicate drier summer conditions. The chironomid records are poor. The MIS 1 (7–0 cal kyr BP) pollen spectra indicate shrub-tundra vegetation. The chironomid fauna is sparse and not diverse. The chironomid-based TJuly reconstruction supports similar-as-today temperatures at 6.4–4.4 cal kyr BP. Diatoms were recorded only after about 6.4 cal kyr BP. The Sobo-Sise Yedoma record preserves traces of the West Beringian tundra-steppe that maintained the Mammoth fauna including rare evidence for woolly rhinoceros’ presence. Chironomid-based TJuly reconstructions complement previous plant-macrofossil based TJuly of regional MIS 3 records. Our study from the eastern Lena Delta fits into and extends previous paleo-ecological Yedoma studies to characterize Beringian paleo-environments in the Laptev Sea coastal region
A vibration-insensitive optical cavity and absolute determination of its ultrahigh stability
We use the three-cornered-hat method to evaluate the absolute frequency
stabilities of three different ultrastable reference cavities, one of which has
a vibration-insensitive design that does not even require vibration isolation.
An Nd:YAG laser and a diode laser are implemented as light sources. We observe
Hz beat note linewidths between all three cavities. The measurement
demonstrates that the vibration-insensitive cavity has a good frequency
stability over the entire measurement time from 100 s to 200 s. An
absolute, correlation-removed Allan deviation of at 1 s of
this cavity is obtained, giving a frequency uncertainty of only 0.44 Hz.Comment: 13 pages, 10 figure
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