2,010 research outputs found
Isoperiodic deformations of the acoustic operator and periodic solutions of the Harry Dym equation
We consider the problem of describing the possible spectra of an acoustic
operator with a periodic finite-gap density. We construct flows on the moduli
space of algebraic Riemann surfaces that preserve the periods of the
corresponding operator. By a suitable extension of the phase space, these
equations can be written with quadratic irrationalities.Comment: 15 page
Hemispheric Asymmetry and Stress Exposure Model in a Professional Evaluation Situation
The urgency of the study on the system of psychophysiological and psychological (temperamental and personal) factors of stress exposure in a situation of professional evaluation of the subjects is considered. The results of the empirical study of stress factors including psychophysiological, temperological and personal characteristics of the subjects are given. The analysis is made with the use of hardware–software system ‘Aktivatsiometr 9К’ by Y.А. Tsagarelli to detect psychophysiological parameters (functional hemispheric asymmetry, activation of the brain hemispheres, strength and lability of the nervous system), «Structure of temperament questionary» by V.М. Rusalov, and diagnosis of the strategic options for choosing a life journey ofthe ‘Typology of Personal Choice’ by V.G. Gryazeva-Dobshinskaya and A.S. Maltseva. Individually typological, as well as dynamic and activity-situational (in a situation of professional evaluation) characteristics of activation and hemispheric asymmetry of the subjects are calculated. Stress reaction is detected, provided individual-typological and activity situational characteristics of activation of the subjects differ by more than 1.5 times. Fifty-six senior students aging between 20 and 25 are the sample of the analysis. The sample is divided into two groups in accordance with the response to the situation of assessment of professional competence: group 1 (n1 = 19 people) with a detected stress reaction, group 2 (n1 = 37 people), in which the stress reactionis not detected. The correctness of the obtained differentiation in the groups of students, differing in the system of indicators of psychophysiological, temperological and personal characteristics is proved with the help of discriminate analysis. The model of stress exposure in a situation of professional evaluation is developed.
Keywords: functional hemispheric asymmetry, everyday stress, professional evaluation, temperamental characteristics, personal choic
Introduction to Dynamic Linear Models for Time Series Analysis
Dynamic linear models (DLM) offer a very generic framework to analyse time
series data. Many classical time series models can be formulated as DLMs,
including ARMA models and standard multiple linear regression models. The
models can be seen as general regression models where the coefficients can vary
in time. In addition, they allow for a state space representation and a
formulation as hierarchical statistical models, which in turn is the key for
efficient estimation by Kalman formulas and by Markov chain Monte Carlo (MCMC)
methods. A dynamic linear model can handle non-stationary processes, missing
values and non-uniform sampling as well as observations with varying
accuracies. This chapter gives an introduction to DLM and shows how to build
various useful models for analysing trends and other sources of variability in
geodetic time series.Comment: A chapter submitted to a book with a proposed title: Geodetic Time
Series Analysis and Applications, editors. J.-P. Montillet and M. Bo
Model testing of radioactive contamination Cs-137 of soils and bottom sediments in the Romachka river (Tomsk region, Russia)
This paper presents results of testing models for the radioactive contamination of river water and bottom sediments by 137Cs. The scenario for the model testing is based on data from the Romashka River, which was contaminated as a result of accidents at the Siberian Chemical Combine (Russia, Region of Tomsk). The input data include the following: estimates of inventories of 137Cs in the floodplain of the downstream part of Romashka River; the estimated annual runoff of 137Cs from the downstream part of Romachka River; data on the precipitation, hydrological and hydrochemical characteristics of the river. The endpoints of the scenario are model predictions of the activity concentrations of 137Cs in water and bottom sediments along the Romachka River in 2012-2013. Calculations for the Romashka scenario were performed by the Institute of radioprotection and nuclear safety (model CASTEAUR and HAMSTER. As a whole, the radionuclide predictions for137Cs for all considered models. At the same time the CASTEAUR model estimate the activity concentrations of 137Cs and in water more precisely than in bottom sediments
Improvement of Calculation Methods for Heat Transfer Factor in Iron Ore Pellet Bed
For the sake of improving the calculation procedure for heat transfer in metallurgical unit dense beds a number of experiments has been carried out that allow adjustment of the heat transfer factor between the gas flow and the pellets in the course of heating. In the course of analysis, a permanent channeling flow was detected in thepellet bed at Re = 100 – 1400. The heat transfer factor was calculated and the pellet temperature was determined in the course of heating within ± 11.4∘C.
Keywords: heat transfer in bed, pellet firing, dense bed, heat transfer factor, hydrodynamic resistance, gas flo
Tariffs Formation on oil transportation
Oil transportation via trunk pipelines is an important part of the oil industry's activity. The main instrument of tariff regulation is the method of tariffs formation. Three methods of tariffs formation such as the method of economically justified costs (the Cost plus method), the method of economically justified return on investment capital (the RAB method), and the method of tariffs indexation were considered
Geotechnical properties of gullying in Tomsk Oblast
The article deals with causes, conditions and factors of gullying in Tomsk Oblast, the case of site Grodnenskaya. A nuclear-power station was planned to be constructed in Closed Administrative Territorial Unit Seversk, which led to geotechnical investigation of the area to study the geological processes developing there. The investigation included reconnaissance traverse of the area, geological and geomorphic descriptions, and sampling. The area and percentage of the territory affected by the geological processes were estimated. As a result, it was proved that the geological processes of the area are conditioned by surface water activity leading to gullying and river erosion, and by both ground water and surface water activity resulting in bog formation. It appears that gullying is caused not only by natural factors but also by technogenic ones
Lamellodiscus aff. euzeti Diamanka, Boudaya, Toguebaye & Pariselle, 2011 (Monogenea: Diplectanidae) from the gills of Cheimerius nufar (Valenciennes) (Pisces: Sparidae) collected in the Arabian Sea, with comments on the distribution, specificity and historical biogeography of Lamellodiscus spp.
Specimens of Lamellodiscus Johnston & Tiegs, 1922 (Monogenea: Diplectanidae) were collected from the gills of Cheimerius nufar (Valenciennes) (Sparidae) in the Arabian Sea. All of these parasites belonged to one and the same species, which is morphologically very close to L. euzeti Diamanka, Boudaya, Toguebaye & Pariselle, 2011. A different host, distant locality and small morphological differences compared with the original description of L. euzeti acted as a stimulus for a detailed redescription. The specimens from the Arabian Sea differ slightly in the details of the male copulatory organ (MCO) from the type-specimens of L. euzeti, which were re-examined, and from the respective drawings in its original description. Such differences include a longer inner process of the large element of the accessory piece associated with the proximal part of the copulatory tube, a longer point on the small element of the accessory piece associated with the distal part of the copulatory tube, and the presence of a smooth or slightly folded inner margin of this element rather than structures resembling spines which occur in the typespecimens of L. euzeti. Therefore, the present specimens infecting C. nufar in the Indo-Pacific may represent a different, but morphologically very similar species to the Atlantic form L. euzeti; consequently, they are recognised here as Lamellodiscus aff. euzeti. This form belongs to the ‘ignoratus s. str.’ subgroup of the genus. The composition of this subgroup is redefined to comprise 17 species, including L. corallinus Paperna, 1965 but excluding L. acanthopagri Roubal, 1981, and the morphology of the MCO of representatives of this group is clarified. A link between the diversity of Lamellodiscus species and the ancestral origin of present-day sparid species in the Tethys Sea is suggested. It is shown that Lamellodiscus spp. exhibit rather high levels of specificity to their hosts, since half of them parasitise only a single host species and c.90% infect closely related host species. Comparison of the levels of host-specificity of the species of this genus with other narrowly specific genera of the Dactylogyridea revealed that their estimations are comparable. The possibility of intrahost speciation within Lamellodiscus is discussed. It is shown that a co-evolutionary model is more discernible if it includes data on the occurrence of morphologically similar species from different regions and host taxa
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