601 research outputs found
Methodology of design of the thin steel strip cold rolling energy efficient technology
The article states basic principles of the methodology of design of the thin steel strip production energy efficient technology, according to which the design process is structurally divided into seven interrelated modules of certain functions. Implementation of the represented approach resulted in the efficient technical mode of rolling providing reduction of overall power consumption subject to compliance with the requirements to quality parameters of the strip
Imitation forecast of railway system operation in a macroregion
The article describes an analytical and information system that was used for forecasting the operation parameters of the railway system in a macroregion of Russia - the Far North. Its economy is focused on the extraction and processing of hydrocarbons, metal production, construction materials, and generate large volumes of exports and inter-regional cargo flows. The region covers an expansive territory and is characterized by harsh weather, an extreme environment, and uneven development of the transportation network. Research into the transportation issues of economic development in such areas presents a challenging task because the region is unique, statistical data are incomplete and classified; there is a hierarchy of businesses and organizations operating in the region that have their own goals and objectives and compete against its other; the region is plagued with social and environmental problems and a lack of administrative integration between individual districts. Using rigorous mathematical tools for assessing transportation infrastructure projects under such conditions is only limited to finding solutions to stand-alone problems and scenario comparison. A model of the applied system that is outlined in the article makes it possible to analyze specific projects of regional railway system development that take into account strategic priorities and goals of the state, social and economic development problems experienced by the neighboring regions, the oil and gas sector and major employers, as well as corporate goals of the sustainable development of railway companies. The application of the model over an extended period of time showed that the analysis of the structure of cargo flows and customers bound to junctions of the transportation network makes it possible to suggest what aspects of the railway infrastructure should be reorganized in line with the development dynamics of economic entities that consume transportation services. The study is built upon a number of projects that were implemented in the north of Tyumen Region and the Yamal- Nenets and Khanty-Mansi autonomous areas of Russia. © 2018 WIT Press.ACKNOWLEDGEMENT The work was supported by Act 211 Government of the Russian Federation, contract № 02.A03.21.0006
Information and simulation model for complex regional transport
The main difficulties related to the economic study of traffic problems are caused by the large number of interrelated factors, hierarchical and competing goals of economic subjects, social and environmental problems of the territory, the degree of administrative independence of its individual parts, as well as the importance of regional economy within the country. The application of rigorous mathematical tools to assess trends in the development of transport infrastructure in these conditions is very limited and is usually reduced to the justification of a few scenarios. The paper offers specific methodological approaches, analytical apparatus with a number of the analyzed conditions and factors, a logical basis for the formation of scenarios in the design of transport systems, including the railway infrastructure of the region. The novelty of the approach used is a combination of accounting features of the territory from the perspective of mineral resources development, and quantification of long-term needs in the freight made on the balance calculations basis. © 2015 WIT Press
Hard-wall Potential Function for Transport Properties of Alkali Metals Vapor
This study demonstrates that the transport properties of alkali metals are
determined principally by the repulsive wall of the pair interaction potential
function. The (hard-wall) Lennard-Jones(15-6) effective pair potential function
is used to calculate transport collision integrals. Accordingly, reduced
collision integrals of K, Rb, and Cs metal vapors are obtained from
Chapman-Enskog solution of the Boltzman equation. The law of corresponding
states based on the experimental-transport reduced collision integral is used
to verify the validity of a LJ(15-6) hybrid potential in describing the
transport properties. LJ(8.5-4) potential function and a simple thermodynamic
argument with the input PVT data of liquid metals provide the required
molecular potential parameters. Values of the predicted viscosity of monatomic
alkali metals vapor are in agreement with typical experimental data with the
average absolute deviation 2.97% for K in the range 700-1500 K, 1.69% for Rb,
and 1.75% for Cs in the range 700-2000 K. In the same way, the values of
predicted thermal conductivity are in agreement with experiment within 2.78%,
3.25%, and 3.63% for K, Rb, and Cs, respectively. The LJ(15-6) hybrid potential
with a hard-wall repulsion character conclusively predicts best transport
properties of the three alkali metals vapor.Comment: 21 pages, 5 figures, 41 reference
Electromagnetic form factors in the J/\psi mass region: The case in favor of additional resonances
Using the results of our recent analysis of e^+e^- annihilation, we plot the
curves for the diagonal and transition form factors of light hadrons in the
time-like region up to the production threshold of an open charm quantum
number. The comparison with existing data on the decays of J/\psi into such
hadrons shows that some new resonance structures may be present in the mass
range between 2 GeVand the J/\psi mass. Searching them may help in a better
understanding of the mass spectrum in both the simple and a more sophisticated
quark models, and in revealing the details of the three-gluon mechanism of the
OZI rule breaking in K\bar K channel.Comment: Formulas are added, typo is corrected, the text is rearranged.
Replaced to match the version accepted in Phys Rev
The study of infl uence of work rolls vibration during cold rolling on the quality of steel strip surface
The article represents the results of the study of work rolls vibration influence on the quality of cold rolled strips on the basis of computer simulation of the rolling process in the DEFORM-2D program. It was determined that the size of alternating shadow zones on the surface of cold rolled strips received through simulation complies with experimental data. The comparison of the strip surface profile change depending on work roll vibration frequency and rolling speed demonstrated that rolling speed increase leads to increase in width of transversal stripes, and increase of vibration frequency leads to their decrease. The results of computer simulation led to the conclusion that vertical vibration of work rolls as the oscillation curve according to the Harmonic Law does not significantly influence the longitudinal strip off gauge. It was found that work rolls horizontal vibration does not influence the nature of deviations in the strip surface profile. Recommendations on use of simulation results are provided to evaluate the strip surface profile
Gauge vortex dynamics at finite mass of bosonic fields
The simple derivation of the string equation of motion adopted in the
nonrelativistic case is presented, paying the special attention to the effects
of finite masses of bosonic fields of an Abelian Higgs model. The role of the
finite mass effects in the evaluation of various topological characteristics of
the closed strings is discussed. The rate of the dissipationless helicity
change is calculated. It is demonstrated how the conservation of the sum of the
twisting and writhing numbers of the string is recovered despite the changing
helicity.Comment: considerably revised to include errata to journal versio
Rho primes in analyzing e+e- annihilation, MARK III, LASS and ARGUS data
The results of an analysis are presented of some recent data on the reactions
, with the
subtracted events, , , , , the decays
,
, upon taking into account both the strong energy
dependence of the partial widths on energy and the previously neglected mixing
of the type resonances. The above effects are shown to exert an
essential influence on the specific values of masses and coupling constants of
heavy resonances and hence are necessary to be accounted for in establishing
their true nature.Comment: 20 pages, ReVTeX, 9 Postscript figures As compared to hep-ph/9607398,
new material concerning the analysis of the ARGUS data on the tau decays into
four pion hadronic states is adde
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