2,229 research outputs found
Factorization effects in a model of unstable particles
The effects of factorization are considered within the framework of the model
of unstable particles with a smeared mass. It is shown that two-particle cross
section and three-particle decay width can be described by the universal
factorized formulae for an unstable particles of an arbitrary spin in an
intermediate state. The exact factorization is caused by the specific structure
of the model unstable-particle propagators. This result is generalized to
complicated scattering and decay-chain processes with unstable particles in
intermediate states. We analyze applicability of the method and evaluate its
accuracy.Comment: 13 pages, 7 figure
Recognition of breaks relief according LIDAR-shooting
This paper discusses methods of recognition breaks relief according LIDAR-shooting. The findings suggested to approximate the cardinal cubic splines: for isohypses - in two-dimensional space, for breaks relief - in three-dimensional space. The results can be used in tasks of tracking the dynamics of changes in the terrainВ данной работе рассмотрены методы распознавания изломов рельефа по данным LIDAR-съемки. Полученные данные предложено аппроксимировать кардинальными кубическими сплайнами: для изогипс ? в двумерном пространстве, для изломов рельефа – в трехмерном пространстве. Результаты работы могут быть использованы в задачах отслеживания динамики изменения рельефа местности
Stress fields and energy of disclination-type defects in zones of localized elastic distortions
This paper studies theoretically the elastically deformed state and analyzes deformation mechanisms in nanocrystals in the zones of localized elastic distortions and related disclination-type defects, such as dipole, quadrupole and multipole of partial disclinations. Significant differences in the energies of quadrupole and multipole configurations in comparison with nanodipole are revealed. The mechanism of deformation localization in the field of elastic distortions is proposed, which is a quasi-periodic sequence of formation and relaxation of various disclination ensembles with a periodic change in the energy of the defect
Radioastron flight operations
Radioastron is a space-based very-long-baseline interferometry (VLBI) mission to be operational in the mid-90's. The spacecraft and space radio telescope (SRT) will be designed, manufactured, and launched by the Russians. The United States is constructing a DSN subnet to be used in conjunction with a Russian subnet for Radioastron SRT science data acquisition, phase link, and spacecraft and science payload health monitoring. Command and control will be performed from a Russian tracking facility. In addition to the flight element, the network of ground radio telescopes which will be performing co-observations with the space telescope are essential to the mission. Observatories in 39 locations around the world are expected to participate in the mission. Some aspects of the mission that have helped shaped the flight operations concept are: separate radio channels will be provided for spacecraft operations and for phase link and science data acquisition; 80-90 percent of the spacecraft operational time will be spent in an autonomous mode; and, mission scheduling must take into account not only spacecraft and science payload constraints, but tracking station and ground observatory availability as well. This paper will describe the flight operations system design for translating the Radioastron science program into spacecraft executed events. Planning for in-orbit checkout and contingency response will also be discussed
Geological-morphological description of the Ishtar Terra (photomap of the Venusian surface sheet B-5)
The main part of the Ishtar Terra east of the Maxwell Montes is covered with systems of areal dislocations of several directions, which are called Parquet. According to the structural patterns these may be divided into: (1) the central stable block; (2) the lesser peripheral blocks separated from the central one by gaps and grabens; (3) the zones of mobilized parquet, whose substance flowed downward at an incline in the directions away from the central block in the form of plastic flows; and (4) the partially parqueted lava sheets. The Maxwell Montes were formed as a result of the collision between the central parquet block and the Lakshmi Planum
The state of hemostasis in pregnant women with hydramnion
Purpose. To determine the state of various stages of hemostasis in pregnant women with
hydramnion as a risk factor for premature detachment of the placenta.
Results. There was investigated the state of hemostasis in pregnant women with hydramnion
by low piezoelectric thromboelastography (LPTEG) and standard coagulogram. According to
the LPTEG results this group of women was found to have increased plasma coagulation
potential manifested in elevated constant thrombin activity (TAC) by 76.8%, the intensity of
coagulation drive (ICD) by 74.9%, maximum clot density (MA) by 16.8%, shortening of
coagulation time (T3) by 7.8% and inhibition of fibrinolysis manifested by decrease in
retraction intensity and clot lysis (RICL) by 67.7% (p<0.05).
Conclusions. The state of hemostasis in pregnant women with hydramnion is characterized
by increased plasma coagulation and inhibition of fibrinolysis potential that are factors of
preparing the woman’s body for the upcoming birth to control and minimize blood loss
Insurance as a tool to maintain the agrobusiness financial stability
The article is devoted to the Russian system of agricultural insurance as an important tool for maintaining the financial stability of the industry. The historical aspect of the formation mechanism of the insurance agrobusiness in Russia is discussed; the main challenges of its current development with market participants are estimate
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