Pitchfork bifurcations in blood-cell shaped dipolar Bose-Einstein condensates

We demonstrate that the method of coupled Gaussian wave packets is a full-fledged alternative to direct numerical solutions of the Gross-Pitaevskii equation of condensates with electromagnetically induced attractive 1/r interaction, or with dipole-dipole interaction. Moreover, Gaussian wave packets are superior in that they are capable of producing both stable and unstable stationary solutions, and thus of giving access to yet unexplored regions of the space of solutions of the Gross-Pitaevskii equation. We apply the method to clarify the theoretical nature of the collapse mechanism of blood-cell shaped dipolar condensates: On the route to collapse the condensate passes through a pitchfork bifurcation, where the ground state itself turns unstable, before it finally vanishes in a tangent bifurcation.Comment: 5 pages, 4 figures, submitted to Phys. Rev.

Electronic interaction in tax administration

In this article ways electronic interaction of tax authorities and taxpayers are considered. Prospects of tax department are also considered

Variational methods with coupled Gaussian functions for Bose-Einstein condensates with long-range interactions. II. Applications

Bose-Einstein condensates with an attractive 1/r interaction and with dipole-dipole interaction are investigated in the framework of the Gaussian variational ansatz introduced by S. Rau, J. Main, and G. Wunner [Phys. Rev. A, submitted]. We demonstrate that the method of coupled Gaussian wave packets is a full-fledged alternative to direct numerical solutions of the Gross-Pitaevskii equation, or even superior in that coupled Gaussians are capable of producing both, stable and unstable states of the Gross-Pitaevskii equation, and thus of giving access to yet unexplored regions of the space of solutions of the Gross-Pitaevskii equation. As an alternative to numerical solutions of the Bogoliubov-de Gennes equations, the stability of the stationary condensate wave functions is investigated by analyzing the stability properties of the dynamical equations of motion for the Gaussian variational parameters in the local vicinity of the stationary fixed points. For blood-cell-shaped dipolar condensates it is shown that on the route to collapse the condensate passes through a pitchfork bifurcation, where the ground state itself turns unstable, before it finally vanishes in a tangent bifurcation.Comment: 14 pages, 14 figures, submitted to Phys. Rev. A, some equations correcte

Изотопный состав и радиационные характеристики отработавшего топливного блока ВТГР

В ходе настоящих исследований создана расчетная модель эквивалентной ячейки ВГТРУ, а также трехмерная модель топливного блока для определения радиационных характеристик ОЯТ ВГТРУ. В численных экспериментах выполнен расчет изотопного состава ОЯТ топливного блока ВГТРУ. Проведена расчетная оценка функционалов необходимых для разработки процедур и регламентов обращения с ОЯТ в ЯТЦ нового поколения.In this work a computational 3-D model of core cell and fuel block of HGTRU were created. In numerical experiments, the isotopic composition of SNF of the HGTRU fuel block was calculated. A calculation estimation of the functionals necessary for the development of procedures and regulations for the management of SNF in a new generation nuclear fuel cycle was carried out. The most important for the development of procedures and regulations for the SNF management in a nuclear fuel cycle of new generation neutron and gamma flux functionals were calculated

Економічний менеджмент підприємства і суспільний інноваційний розвиток в умовах ризиків

The knowledge of surface electromyography (SEMG) and the number of applications have increased considerably during the past ten years. However, most methodological developments have taken place locally, resulting in different methodologies among the different groups of users. A specific objective of the European concerted action SENIAM (surface EMG for a non-invasive assessment of muscles) was, besides creating more collaboration among the various European groups, to develop recommendations on sensors, sensor placement, signal processing and modeling. This paper will present the process and the results of the development of the recommendations for the SEMG sensors and sensor placement procedures. Execution of the SENIAM sensor tasks, in the period 1996–1999, has been handled in a number of partly parallel and partly sequential activities. A literature scan was carried out on the use of sensors and sensor placement procedures in European laboratories. In total, 144 peer-reviewed papers were scanned on the applied SEMG sensor properties and sensor placement procedures. This showed a large variability of methodology as well as a rather insufficient description. A special workshop provided an overview on the scientific and clinical knowledge of the effects of sensor properties and sensor placement procedures on the SEMG characteristics. Based on the inventory, the results of the topical workshop and generally accepted state-of-the-art knowledge, a first proposal for sensors and sensor placement procedures was defined. Besides containing a general procedure and recommendations for sensor placement, this was worked out in detail for 27 different muscles. This proposal was evaluated in several European laboratories with respect to technical and practical aspects and also sent to all members of the SENIAM club (>100 members) together with a questionnaire to obtain their comments. Based on this evaluation the final recommendations of SENIAM were made and published (SENIAM 8: European recommendations for surface electromyography, 1999), both as a booklet and as a CD-ROM. In this way a common body of knowledge has been created on SEMG sensors and sensor placement properties as well as practical guidelines for the proper use of SEMG

Исследование параметров плазмы реактивного магнетронного разряда с помощью зонда Ленгмюра

One of the most prospective methods of making the biocompatible coatings is reactive magnetron sputtering. It allows obtaining coatings with well controllable chemical composition. In order to control magnetron plasma parametersa Langmuir probe is widely used. A method for probe data processing has been developed. It includes raw data averaging and least-square methods for determining of plasma parameters such as electron temperature and ion density. The averaging is used in order to reduce an impact of data oscillations caused by proximity of probe and discharge frequencies. Using the method, plasma discharge parameters dependence on reactive gas mixture type has been investigated