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1062. Analysis of nonradial oscillations of rapidly rotating δ Scuti stars
- Creator:
- Walker, Gordon, Yang, Stephenson, McDowall, Gennen, and Fahlman, Gregory
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- astronomy, δ Scuti stars, and nonradial oscillations
- Language:
- Czech
- Description:
- We have reported elsewhere the discovery of apparently high-degree nonradial oscillations for the four rapidly rotating (-120 kms^-1) δ Scuti stars: 21 Mon, κ^2 Boo, ν UMa, and o Eri. Here we discuss some of the techniques which we have used to isolate and to analyse the time varying components (-1% continuum) of the line profiles. They are best seen after subtraction of an average, filtered spectrum. For the δ Scuti stars, periodograms of the residual spectra show several peaks, some of which can be identified with the degrees of oscillation found in our preliminary analysis. In the latter, values of |m| were estimated from the sub-feature accelerations and delay in transit of the features. While one mode tends to dominate it is clear that often more than one Is present. The sub-features are not always equally spaced and they can show phase changes and doubling. While nrp provides an adequate, general description of the phenomena, we are probably seeing only part of something more complex. The immediate challenge is to combine the results from many lines plus higher spectral resolution to improve the visibility of the time varying features by at least an order of magnitude.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1063. Analysis of state space of RNNs trained on a chaotic symbolic sequence
- Creator:
- Makula, Matej and Beňušková, Ľubica
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- recurrent neural networks, state space, clustering, architectural bias, and information gain
- Language:
- English
- Description:
- We investigate Solutions provided by the finite-context predictive model called neural prediction machine (NPM) built on the recurrent layer of two types of recurrent neural networks (RNNs). One type is the first-order Elman’s simple recurrent network (SRN) trained for the next symbol prediction by the technique of extended Kalman filter (EKF). The other type of RNN is an interesting unsupervised counterpart to the “claissical” SRN, that is a recurrent version of the Bienenstock, Cooper, Munro (BCM) network that performs a kind of time-conditional projection pursuit. As experimental data we chose a complex symbolic sequence with both long and short memory structures. We compared the Solutions achieved by both types of the RNNs with Markov models to find out whether training can improve initial Solutions reached by random network dynamics that can be interpreted as an iterated function system (IFS). The results of our simulations indicate that SRN trained by EKF achieves better next symbol prediction than its unsupervised counterpart. Recurrent BCM network can provide only the Markovian solution that is not able to cover long memory structures in sequence and thus beat SRN.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1064. Analysis of structural properties of Petri nets based on product incidence matrix
- Creator:
- Ji, Guangyou and Wang, Mingzhe
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Petri net, structural property, linear inequality, and product incidence matrix
- Language:
- English
- Description:
- This paper presents some structural properties of a generalized Petri net (PN) with an algorithm to determine the (partial) conservativeness and (partial) consistency of the net. A product incidence matrix A=CCT or A~=CTC is defined and used to further improve the relations among PNs, linear inequalities and matrix analysis. Thus, based on Cramer's Rule, a new approach for the study of the solution of a linear system is given in terms of certain sub-determinants of the coefficient matrix and an efficient algorithm is proposed to compute these sub-determinants. The paper extends the common necessary and/or sufficient conditions for conservativeness and consistency in previous papers and some examples are designed to explain the conclusions finally.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1065. Analysis of the flare evolution in the emission measure-temperature diagrams for selected events observed by SMM
- Creator:
- Sylwester, B., Sylwester, J., Siarkowski, M., Fludra, A., and Serio, S.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Solar Maximum Mission satellite and flare evolution
- Language:
- Czech
- Description:
- We have investigated the time profiles of flare heating function for selected flares based on the analysis of their evolutionary paths in the Emission Measure - Temperature diagrams. The emission measures and the temperatures werederived from the Ca XIX soft X-ray spectra observed by the Bent Crystal Spectrometer aboard the Solar Maximum Mission satellite. Interpretation of these diagrams allows to study the rate of energy deposition during both rise and decay phase of flares. The investigation of (EM-T) diagrams during the decay phase allows furthermore for determination of effective length/cross-sectional area ratio of the flaring loop. We háve used the value of this ratio to derive the effective loop cross-sectional radius and the plasma density from deconvolved Fiat Crystal Spectrometer soft X-ray images.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1066. Analysis of the flows of incompressible fluids with pressure dependent viscosity fulfilling $\nu (p, \cdot ) \to + \infty $ as $p \to +\infty $
- Creator:
- Bulíček, M., Málek, Josef, and Rajagopal, Kumbakonam R.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- existence, weak solution, incompressible fluid, pressure-dependent viscosity, shear-dependent viscosity, and spatially periodic problem
- Language:
- English
- Description:
- Over a large range of the pressure, one cannot ignore the fact that the viscosity grows significantly (even exponentially) with increasing pressure. This paper concerns long-time and large-data existence results for a generalization of the Navier-Stokes fluid whose viscosity depends on the shear rate and the pressure. The novelty of this result stems from the fact that we allow the viscosity to be an unbounded function of pressure as it becomes infinite. In order to include a large class of viscosities and in order to explain the main idea in as simple a manner as possible, we restrict ourselves to a discussion of the spatially periodic problem.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1067. Analysis of thermally-induced transformations of silica rocks after high temperature heat treatment
- Creator:
- Geng, Jishi, Sun, Qiang, Zhang, Yuchun, and Zhang, Yuliang
- Format:
- print, bez média, and svazek
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Geologie. Meteorologie. Klimatologie, vysoké teploty, high temperatures, silica rocks, non-destructive analytical method, thermal expansion, 7, and 551
- Language:
- English
- Description:
- High temperature alters the internal microstructure of rocks and consequently changes the physical and mechanical properties of rocks. Many studies have been carried out to examine the transformations in the microstructures of rocks under high temperature through near infrared spectroscopy (NIR), Raman spectroscopy, or thermo gravimetric analysis (TGA). The current review synthesizes the data from a number of literatures and summarizes the major transformations of silica rocks under high temperature. The analysis shows that silica rocks starts to lose the water adsorbed in open pores upon heating at about 150 °C. At 200-300 °C, the reaction between SiOH (silanole) in the rocks generates new Si-O-Si bonds as well as H2O, and decreases the open pores. The rocks undergo volume expansion at >550 °C, and the volume contracts and forms new micro pores or cracks which play an important role in the evacuation of the water., Jishi Geng, Qiang Sun, Yuchun Zhang and Yuliang Zhang., and Obsahuje bibliografické odkazy
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1068. Analysis of time references in natural language by means of transparent intensional logic
- Creator:
- Duží, Marie and Macek, Jakub
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- calendar, Gregorian calendar, Julian calendar, time duration, time interval, TIL, time point, time span, transparent intensional logic, typed system, and year
- Language:
- Slovak
- Description:
- In this paper, we deal with sentences containing time references like ''five years ago'', ''three years older'', ''in five seconds''. It turns out that such sentences are pragmatically incomplete, because there is an elliptic reference to a calendar that makes it possible to determine the length of the time interval associated with a time duration like a year, month, day, or to compute the time interval denoted by terms like ''February 29, 2016''. Since Transparent Intensional Logic (TIL) takes into account two modal parameters, namely possible worlds of type ω and times of type τ, and this system is particularly apt for the analysis of natural language expressions, our background theory is TIL. Within this system, we define time intervals, calendar time durations, and last but not least a method for adding and multiplying time durations in a way that takes into account the leap days and leap seconds. As sample applications, we analyse two sentences, to wit, ''A year has 365 days'' and ''Adam is 5 years older than Bill''. and V tomto článku se zabýváme věty obsahujícími časové odkazy jako ''před pěti lety'', ''o tři roky starší'', ''za pět sekund''. Ukazuje se, že takové věty jsou pragmaticky neúplné, protože existuje eliptický odkaz na kalendář, který umožňuje určit délku časového intervalu spojeného s časovým obdobím jako rok, měsíc, den nebo vypočítat časový interval označované slovy ''29. února 2016''. Vzhledem k tomu, že Transparentní Intenzivní Logika (TIL) zohledňuje dva modální parametry, jmenovitě možné světy typu ω a časy typu τ, a tento systém je obzvláště vhodný pro analýzu přirozených jazykových výrazů, je naší teorií pozadí TIL. V rámci tohoto systému definujeme časové intervaly, trvání kalendáře, a v neposlední řadě metoda pro přidání a násobení doby trvání způsobem, který bere v úvahu skokové a skokové sekundy. Jako vzorové aplikace analyzujeme dvě věty s názvem ''rok má 365 dní'' a ''Adam je o 5 let starší než Bill''.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1069. Analytic method
- Creator:
- Kosterec, Miloš
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- analytic method, analytic proposition, closure, instruction, and knowledge base
- Language:
- Slovak
- Description:
- This paper proposes a non-trivial definition of the notion of analytic method. Working within the so-called instructional model of method, I distinguish three kinds of instructions which occur in methods: selective, executive, and declarative instructions. I discuss the relation between each of these and the analyticity of a method. Then I define the notions of an analytic use of an instruction and of an analytic instruction, which are at the basis of the proposed definition of an analytic method. Finally, I discuss the issue of circularity in the presented model which arises if we consider a finite agent testing a method for analyticity., Tato práce navrhuje netriviální definici pojmu analytická metoda. V rámci tzv. Instruktážního modelu metody rozlišuji tři druhy instrukcí, které se vyskytují v metodách: selektivní, exekutivní a deklarativní . Diskutuji o vztahu mezi každou z nich a analytičnosti metody. Dále definuji pojmy analytického použití instrukce a analytické instrukce , které jsou základem navrhované definice analytické metody. Závěrem se zabývám otázkou kruhovitosti v prezentovaném modelu, která vzniká, pokud uvažujeme konečný agent testující metodu analyticity., and Miloš Kosterec
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1070. Analytical derivation of time spectral rigidity for thermodynamic traffic gas
- Creator:
- Krbálek, Milan
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- thermodynamic traffic gas, clearance distribution, and spectral rigidity
- Language:
- English
- Description:
- We introduce an one-dimensional thermodynamical particle model which is efficient in predictions about a microscopical structure of animal/human groups. For such a model we present analytical calculations leading to formulae for time clearance distribution as well as for time spectral rigidity. Furthermore, the results obtained are reformulated in terms of vehicular traffic theory and consecutively compared to experimental traffic data.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public