5,495 research outputs found
Methodology for building a functionally stable intelligent information system of a manufacturing enterprise
The article analyzes the concept of process management in an industrial enterprise, which provides functional stability of technological processes using information systems of various types and allows to increase productivity of all production centers while reducing the number of people employed in production and the impact of various destabilizing factors. The research of existing mathematical models of functionally stable complex technical systems and formalization of the main types of procedures of the process of functioning of the intellectual information system of the enterprise is carried out. The method of ensuring the properties of functional stability of the intelligent information system of the enterprise is improved by presenting the functioning of the system in the form of a formalized process, in which the main types of procedures are accumulation of tests, analysis of test links, diagnosing a failed module and restoring the system. This technique allows to ensure the property of functional stability of the information system of the enterprise.
Pages of the article in the issue: 116 - 127
Language of the article: Ukrainia
Energy Relaxation at a Hot-Electron Vortex Instability
At high dissipation levels, vortex motion in a superconducting film has been
observed to become unstable at a certain critical vortex velocity v*. At
substrate temperatures substantially below Tc, the observed behavior can be
accounted for by a model in which the electrons reach an elevated temperature
relative to the phonons and the substrate. Here we examine the underlying
assumptions concerning energy flow and relaxation times in this model. A
calculation of the rate of energy transfer from the electron gas to the lattice
finds that at the instability, the electronic temperature reaches a very high
value close to the critical temperature. Our calculated energy relaxation times
are consistent with those deduced from the experiments. We also estimate the
phonon mean free path and assess its effect on the flow of energy in the film.Comment: 8 pages, 7 figure
Dynamics of vortex penetration, jumpwise instabilities and nonlinear surface resistance of type-II superconductors in strong rf fields
We consider nonlinear dynamics of a single vortex in a superconductor in a
strong rf magnetic field . Using the London theory, we
calculate the dissipated power , and the transient time scales
of vortex motion for the linear Bardeen-Stephen viscous drag force, which
results in unphysically high vortex velocities during vortex penetration
through the oscillating surface barrier. It is shown that penetration of a
single vortex through the ac surface barrier always involves penetration of an
antivortex and the subsequent annihilation of the vortex antivortex pairs.
Using the nonlinear Larkin-Ovchinnikov (LO) viscous drag force at higher vortex
velocities results in a jump-wise vortex penetration through the surface
barrier and a significant increase of the dissipated power. We calculate the
effect of dissipation on nonlinear vortex viscosity and the rf vortex
dynamics and show that it can also result in the LO-type behavior,
instabilities, and thermal localization of penetrating vortex channels. We
propose a thermal feedback model of , which not only results in the LO
dependence of for a steady-state motion, but also takes into account
retardation of temperature field around rapidly accelerating vortex, and a
long-range interaction with the surface. We also address the effect of pinning
on the nonlinear rf vortex dynamics and the effect of trapped magnetic flux on
the surface resistance calculated as a function or rf frequency and
field. It is shown that trapped flux can result in a temperature-independent
residual resistance at low , and a hysteretic low-field dependence of
, which can {\it decrease} as is increased, reaching a minimum
at much smaller than the thermodynamic critical field .Comment: 18 figure
Long-term operation of a multi-channel cosmic muon system based on scintillation counters with MRS APD light readout
A Cosmic Ray Test Facility (CRTF) is the first large-scale implementation of
a scintillation triggering system based on a new scintillation technique known
as START. In START, the scintillation light is collected and transported by WLS
optical fibers, while light detection is performed by pairs of avalanche
photodiodes with the Metal-Resistor-Semiconductor structure operated in the
Geiger mode (MRS APD). START delivers 100% efficiency of cosmic muon detection,
while its intrinsic noise level is less than 10^{-2} Hz. CRTF, consisting of
160 START channels, has been continuously operated by the ALICE TOF
collaboration for more than 25 000 hours, and has demonstrated a high level of
stability. Fewer than 10% of MRS APDs had to be replaced during this period.Comment: Proceedings of NDIP-2008. 8 pages, 8 figures, 6 reference
Rearrangement of the vortex lattice due to instabilities of vortex flow
With increasing applied current we show that the moving vortex lattice
changes its structure from a triangular one to a set of parallel vortex rows in
a pinning free superconductor. This effect originates from the change of the
shape of the vortex core due to non-equilibrium effects (similar to the
mechanism of vortex motion instability in the Larkin-Ovchinnikov theory). The
moving vortex creates a deficit of quasiparticles in front of its motion and an
excess of quasiparticles behind the core of the moving vortex. This results in
the appearance of a wake (region with suppressed order parameter) behind the
vortex which attracts other vortices resulting in an effective
direction-dependent interaction between vortices. When the vortex velocity
reaches the critical value quasi-phase slip lines (lines with fast vortex
motion) appear which may coexist with slowly moving vortices between such
lines. Our results are found within the framework of the time-dependent
Ginzburg-Landau equations and are strictly valid when the coherence length
is larger or comparable with the decay length of the
non-equilibrium quasiparticle distribution function. We qualitatively explain
experiments on the instability of vortex flow at low magnetic fields when the
distance between vortices . We speculate that a
similar instability of the vortex lattice should exist for even when
.Comment: 10 pages, 11 figure
Strategic Region of Southeast Asia: The Formation of a Security Architecture
The present study is aimed at studying the experience of forming a regional security architecture on the example of Southeast Asia.Aim. Study and generalization of the historical experience of the formation of the security architecture in Southeast Asia and its current state, participation in a scientific discussion on the problems of the Eurasian space.Tasks. To carry out an express analysis of the fundamental decisions of the Association of Southeast Asian Nations (hereinafter — ASEAN, the Association) on security issues, their effectiveness in regional political practice; to identify the main problems of the process of forming a regional security system and the impact of global instability, contradictory bilateral relations between the states of the region; to determine the reasons for the eclecticism of its current state, as well as different approaches to assessing the results of ASEAN’s activities over the entire period of its existence, caused by the lag in making operational decisions on security in the conditions of real modern socio-political and economic processes; to identify the main mechanisms and tools of the Southeast regional security architecture from the East Asian Summit to the Committees ASEAN by areas of activity, from Joint Statements to Programs, including the ASEAN Regional Security Architecture Program, and Action Plans.Methodology. Using historical, comparative and structural-functional methods based on the main content of the documents of the ASEAN Regional Forum, the East Asian Summit, the Russia-ASEAN dialogue program, as well as research models of Russian and foreign scientists and experts, existing problems were identified, the process of forming a regional security system, and the need to study the experience of ASEAN was justified.Results. The study showed the general and special features of the process of formation of the regional security system of Southeast Asia and regional security architectures in Central Asia and Europe. It is confirmed that the current global uncertainty and instability contribute to the formation of a trend towards regional coalitions and the strengthening of regional security architectures. The multidirectional positions of the members of the Association on issues of national and regional security have been revealed. ASEAN uses the experience of other regional coalitions, primarily NATO, in shaping the security architecture. There are problems in the efficiency of decision-making and this has both negative and positive consequences.Conclusions. In contrast to the established Euro-Atlantic security architecture, which excludes a significant part of Europe in the form of the European part of the Russian Federation, the Eurasian strategic space is currently in the process of forming a security system, which includes only certain groups of states. The research is mainly aimed at studying approaches to the content and forms of cooperation between these countries in security issues. Modern global processes negatively affect all levels of security and actualize the problem of strengthening it at the regional level. Even in the difficult conditions of Southeast Asia, ASEAN manages to partially minimize the consequences of challenges, threats and security risks. In the south-eastern strategic region, the problems of protracted conflicts, significant differences in the economic and political development of the member States of the Association still remain unresolved, and this negatively affects the achievement of unity and the development of cooperation relations between the countries of the region, as well as the stabilization of the regional situation. The existing problems in the efficiency of decision-making at the regional level have both negative and positive consequences. They are currently balanced. Participation in the work of various international institutions is of great political importance, and has an impact on the status of subjects of the global or regional political process. Participation in the dialogue programs of the ASEAN of Russia is justified and contributes to the continuation of contacts with the countries of Southeast Asia. The experience of the long-term existence of the regional coalition can be used in other regions of Eurasia
Financial Security of Eurasia: the Geopolitical Aspect
The article actualizes the main content and problems of implementation of the Monterrey consensus of the International conference on financing for development in the modern geopolitical and geo-economic space, the role of the International monetary Fund and its financial instruments in the Eurasian geopolitical space in this process.Purpose: to show the inconsistency of the financial policies of Western countries, challenges and threats to financial security of developing countries.Historical and comparative methods of research are used.The study revealed the selectivity of economically developed countries in approaches to financial support for developing countries, the use of financial instruments to protect the national interests of individual countries or groups to the detriment of others, the difference in approaches of the West and the East in solving problems of economic development
Steps in the Negative-Differential-Conductivity Regime of a Superconductor
Current-voltage characteristics were measured in the mixed state of
Y1Ba2Cu3O(7-delta) superconducting films in the regime where flux flow becomes
unstable and the differential conductivity dj/dE becomes negative. Under
conditions where its negative slope is steep, the j(E) curve develops a
pronounced staircase like pattern. We attribute the steps in j(E) to the
formation of a dynamical phase consisting of the succesive nucleation of
quantized distortions in the local vortex velocity and flux distribution within
the moving flux matter.Comment: 5 pages, 3 figure
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