1,310 research outputs found
Uniqueness theorem for the non-local ionization source in glow discharge and hollow cathode
The paper is devoted to the proof of the uniqueness theorem for solution of
the equation for the non-local ionization source in a glow discharge and a
hollow cathode in general 3D geometry. The theorem is applied to wide class of
electric field configurations, and to the walls of discharge volume, which have
a property of incomplete absorption of the electrons. Cathode is regarded as
interior singular source, which is placed arbitrarily close to the wall. The
existence of solution is considered also. During the proof of the theorem many
of useful structure formulae are obtained. Elements of the proof structure,
which have arisen, are found to have physical sense. It makes clear physical
construction of non-local electron avalanche, which builds a source of
ionization in glow discharge at low pressures. Last has decisive significance
to understand the hollow cathode discharge configuration and the hollow cathode
effect.Comment: 31 pages. Short text (2 pages) was published in the Book of abstracts
of IV CESPC, August 21 - 25, 2011, Zlatibor, Serbi
Random matrix description of decaying quantum systems
This contribution describes a statistical model for decaying quantum systems
(e.g. photo-dissociation or -ionization). It takes the interference between
direct and indirect decay processes explicitely into account. The resulting
expressions for the partial decay amplitudes and the corresponding cross
sections may be considered a many-channel many-resonance generalization of
Fano's original work on resonance lineshapes [Phys. Rev 124, 1866 (1961)].
A statistical (random matrix) model is then introduced. It allows to describe
chaotic scattering systems with tunable couplings to the decay channels. We
focus on the autocorrelation function of the total (photo) cross section, and
we find that it depends on the same combination of parameters, as the
Fano-parameter distribution. These combinations are statistical variants of the
one-channel Fano parameter. It is thus possible to study Fano interference
(i.e. the interference between direct and indirect decay paths) on the basis of
the autocorrelation function, and thereby in the regime of overlapping
resonances. It allows us, to study the Fano interference in the limit of
strongly overlapping resonances, where we find a persisting effect on the level
of the weak localization correction.Comment: 16 pages, 2 figure
Data linkage for early intervention in the UK: Parental social license and social divisions
Electronic linking of public records and predictive analytics to identify families for preventive early intervention increasingly is promoted by governments. We use the concept of social license to address questions of social legitimacy, agreement, and trust in data linkage and analytics for parents of dependent children, who are the focus of early intervention initiatives in the UK. We review data-steered family policy and early intervention operational service practices. We draw on a consensus baseline analysis of data from a probability-based panel survey of parents, to show that informed consent to data linkage and use is important to all parents, but there are social divisions of knowledge, agreement, and trust. There is more social license for data linkage by services among parents in higher occupation, qualification, and income groups, than among Black parents, lone parents, younger parents, and parents in larger households. These marginalized groups of parents, collectively, are more likely to be the focus of identification for early intervention. We argue that government awareness-raising exercises about the merits of data linkage are likely to bolster existing social license among advantaged parents while running the risk of further disengagement among disadvantaged groups. This is especially where inequalities and forecasting inaccuracies are encoded into early intervention data gathering, linking, and predictive practices, with consequences for a cohesive and equal society
Capacity Assessment Of The System Of Gas Pipelines, Receiving And Transporting Gas Of Inland Production
Today, the majority of gas fields in Ukraine are in the final stages of development, which is characterized by a significant decrease in wellhead pressure, as well as an increased gas-water factor. As is well known, when lowering wellhead pressure arises the problem of ensuring the design capacity of the gas production system as a whole.The main function of the gas pipeline system of the gas producing company of Ukraine is collection of gas from deposits and transport natural gas to consumers.Taking into account the tasks of ensuring the energy independence of Ukraine, as well as the program to build up gas of its own production, the question of assessing the capacity of the gas pipeline system remains relevant, performing the function of collection and transportation.As part of the research, the current state of the gas collection and transportation system is analyzed. The workload of gas pipeline sections in the chain from the wellhead to the consumer is investigated. As a result, it is established that the initial sections of the gas production system are fully loaded. Areas that can be recharged are identified, as a result of which it will reduce the output pressure at the wellheads and stabilize hydrocarbon production.On the basis of the conducted research, it is revealed that one of the alternative methods of increasing the capacity of the gas production system at the initial sections is to increase the equivalent diameter and length of the system by building new gas pipelines. It is also found that the periodic cleaning of pipelines in existing parts of the system prevents the decrease in capacity.It has been established that reducing the backpressure of the system is possible only in conjunction with unloading the system by changing the flow directions, creating centralized gas collection points, as well as retrofitting existing booster compressor stations.The availability of data on the load on the gas transmission system will allow the gas producing company to plan the distribution of gas to areas with available free capacity, while ensuring an increase in the production of its own gas. As a result, when the gas is distributed to areas with partial load, it will prevent excessive pressure losses in the system, as well as provide optimal system operation conditions
Monomial integrals on the classical groups
This paper presents a powerfull method to integrate general monomials on the
classical groups with respect to their invariant (Haar) measure. The method has
first been applied to the orthogonal group in [J. Math. Phys. 43, 3342 (2002)],
and is here used to obtain similar integration formulas for the unitary and the
unitary symplectic group. The integration formulas turn out to be of similar
form. They are all recursive, where the recursion parameter is the number of
column (row) vectors from which the elements in the monomial are taken. This is
an important difference to other integration methods. The integration formulas
are easily implemented in a computer algebra environment, which allows to
obtain analytical expressions very efficiently. Those expressions contain the
matrix dimension as a free parameter.Comment: 16 page
Simulation of static and random errors on Grover's search algorithm implemented in a Ising nuclear spin chain quantum computer with few qubits
We consider Grover's search algorithm on a model quantum computer implemented
on a chain of four or five nuclear spins with first and second neighbour Ising
interactions. Noise is introduced into the system in terms of random
fluctuations of the external fields. By averaging over many repetitions of the
algorithm, the output state becomes effectively a mixed state. We study its
overlap with the nominal output state of the algorithm, which is called
fidelity. We find either an exponential or a Gaussian decay for the fidelity as
a function of the strength of the noise, depending on the type of noise (static
or random) and whether error supression is applied (the 2pi k-method) or not.Comment: 18 pages, 8 figures, extensive revision with new figure
Ways to improve the competitiveness of the economic complex of the Republic of Mordovia
The economic development of the Republic of Mordovia from 1998 to 2013 is analyzed in the article in the context of federal districts of the Russian Federation and regions of the Volga Federal District, the main trends and specifics of the development of economic complex of the Republic of Mordovia are established in comparison with those regions; key factors that affect the level of competitiveness of the regional economic complex of the Republic of Mordovia are determined; the main directions and measures to improve the competitiveness of the economic complex of the region are determined, considering economic, innovative and infrastructure opportunities that conform to the applicable program documents regulating the social and economic development of the Republic of Mordovia. In the article conclusions are made on the need for solving the problem of increasing the competitiveness of the regional economy through the use of its innovation and infrastructure capacities and the possibility of using the experience of the Republic of Mordovia in the implementation of this approach by other subjects of the Russian Federation with the same economic conditions as well as by relatively problem regions that don't have their own resource potential.peer-reviewe
A random matrix approach to decoherence
In order to analyze the effect of chaos or order on the rate of decoherence
in a subsystem, we aim to distinguish effects of the two types of dynamics by
choosing initial states as random product states from two factor spaces
representing two subsystems. We introduce a random matrix model that permits to
vary the coupling strength between the subsystems. The case of strong coupling
is analyzed in detail, and we find no significant differences except for very
low-dimensional spaces.Comment: 11 pages, 5 eps-figure
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