137 research outputs found
Some results of cislunar plasma research
The main results of plasma cislunar investigations, carried out during Luna-19 and Luna-22 spacecraft flights by means of dual frequency dispersion interferrometry, are briefly outlined. It is shown that a thin layer of plasma, with a height of several tens of kilometers and a maximum concentration of the order 1,000 electrons/cu cm exists above the solar illuminated lunar surface. A physical model of the formation and existence of such a plasma in cislunar space is proposed, taking into account the influence of local magnetic areas on the moon
The nighttime ionosphere of Mars from Mars-4 and Mars-5 radio occultation dual-frequency measurements
Dual frequency radio sounding of the Martian nighttime ionosphere was carried out during the exits from behind the planet of the Mars-4 spacecraft on February 2, 1974 and the Mars-5 spacecraft on February 18, 1974. In these experiments, the spacecraft transmitter emitted two coherent monochromatic signals in decimeter and centimeter wavelength ranges. At the Earth receiving station, the reduced phase difference (or frequencies) of these signals was measured. The nighttime ionosphere of Mars measured in both cases had a peak electron density of approximately 5 X 1,000/cu cm at an altitude of 110 to 130 km. At the times of spacecraft exit, the solar zenith angles at the point of occultation were 127 deg and 106 deg, respectively. The height profiles of electron concentration were obtained assuming spherical symmetry of the Martian ionosphere
Multivariate p-dic L-function
We construct multivariate p-adic L-function in the p-adic number fild by
using Washington method.Comment: 9 page
SOME ABSTRACT PROPERTIES OF SEMIGROUPS APPEARING IN SUPERCONFORMAL THEORIES
A new type of semigroups which appears while dealing with
superconformal symmetry in superstring theories is considered. The ideal series
having unusual abstract properties is constructed. Various idealisers are
introduced and studied. The ideal quasicharacter is defined. Green's relations
are found and their connection with the ideal quasicharacter is established.Comment: 11 page
Compaction and flow rule of oxide nanopowders
Transparent Al2O3 ceramics have attracted considerable interest for use in a wide range of optical, electronic and structural applications. The fabrication of these ceramics using powder metallurgy processes requires the development of theoretical approaches to the compaction of nanopowders. In this work, we investigate the compaction processes of two model granular systems imitating Al2O3 nanosized powders. System I is a loosely aggregated powder, and system II is a powder strongly inclined to agglomeration (for instance, calcined powder). The processes of isostatical (uniform), biaxial, and uniaxial compaction as well as uniaxial compaction with simultaneous shear deformation are studied. The energy parameters of compaction such as the energy change of elastic interparticle interactions and dispersion interactions, dissipative energy losses related to the processes of interparticle friction, and the total work of compaction are calculated for all the processes. The nonapplicability of the associated flow rule to the description of deformation processes of oxide nanopowders is shown and an alternative plastic flow rule is suggested. A complete system of determining the relationship of the flow including analytical approximations of yield surfaces is obtained. © 2016 Elsevier B.V
Segregation, mobility and encounters in Jerusalem: The role of public transport infrastructure in connecting the ‘divided city’
This paper assesses ways in which urban segregation is shaped and transformed by Jerusalem’s public transport network, enhancing mobility and potential group encounters. We suggest that segregation should be understood as an issue of mobility and co-presence in public space, rather than the static residential-based segregation that continues to be a central focus of debate in urban studies. We explore public transport infrastructures, considering how their implementation reflects the variety of ways that transport can have impact: segmenting populations, linking populations and/or creating spaces for interaction or conflict between the city’s Jewish Israeli and Arab Palestinian populations. Space syntax network analysis suggests that in the case of Jerusalem, access to public transport is multi-dimensional: as well as providing access to resources, it shapes opportunities for spatial mobility that may either overcome or reinforce area-based housing segregation. We discuss these opportunities in the light of Jerusalem’s on-going ethno-national division in an increasingly fractured urban reality
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