764 research outputs found

    Emission activity of the Be star 60 Cygni

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    In this paper we present results of the spectroscopic analysis of Hα\alpha line profile of the Be star 60 Cygni. We present time evolution of the equivalent width of the Hα\alpha line profiles during years 1992 - 2016 and V/RV/R variation during years 1995 - 2016. We analyzed data from Ond\v{r}ejov Observatory and from BeSS Database. The circumstellar disk of the star was present twice during years 1992 - 2016 and the second cycle shows stronger emission activity. We found out that the formation of the disk takes longer time than the disk extinction (extinction is much steeper than the formation) and that there is no evident period of changes in V/RV/R variation

    Time-dependent spectral-feature variations of stars displaying the B[e] phenomenon III. HD 50138

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    We analyse spectroscopic observations of the B[e] star HD 50138 (MWC 158, V743 Mon, or IRAS 06491-0654), a member of the FS CMa group, obtained over the last twenty years. Four different epochs are identified in the observational data, where the variability of the spectral features is substantially different. Additionally, two long periods of (3 000 +/- 500) and (5 000 +/- 1000) days are found in the variations of the equivalent widths of the H alpha and [OI] 6300 A lines and radial velocities of the H alpha line violet peak. Modest signatures of a regular period of ~34 days in the radial velocities of the H alpha red peak and H beta central depression are found in the season 2013/2014. The H alpha V/R changes indicate a periodicity of ~50 days. The correlations between individual spectral features significantly restricts the model of the object and suggest that it is most likely a binary system with a highly distorted disc with spiral arms around the primary component. At the same time, no obvious signs of the secondary component has been found in the object's spectrum

    Time-dependent spectral-feature variations of stars displaying the B[e] phenomenon; I. V2028 Cyg

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    We present results of nearly six years of spectroscopic observations of the B[e] star V2028 Cyg. The presence of the cold-type absorption lines combined with a hot-type spectrum indicate the binarity of this object. Since B[e] stars are embedded in an extended envelope, the usage of common stellar atmosphere models for the analysis is quite inappropriate. Therefore, we focus on the analysis of the long-term spectral line variations in order to determine the nature of this object. We present the time dependences of the equivalent width and radial velocities of the H alpha line, [O I] 6300 A, Fe II 6427, 6433, and 6456 A lines. The bisector variations and line intensities are shown for the H alpha line. The radial velocities are also measured for the absorption lines of the K component. No periodic variation is found. The observed data show correlations between the measured quantities, which can be used in future modelling

    Reliability of Human Subject - Artificial System Interactions

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    Main problems related to reliability of interaction between human subject and artificial system (namely of the transportation character) are discussed. The paper consists of three mayor parts:The first one is devoted to the theoretical backgrounds of the problem from the both theory of system reliability and neurology/psychology views.Second part presents the discussion of relevant methodologies of the classification and prediction of the reliability decline. The methodology based on EEG pattern analysis is chosen as the appropriate one for the presented task. The key phenomenon of "micro-sleep" is discussed in detail.The last part presents some latest experimental results in context of presented knowledge. Proposals for the future studies are presented at the end of the presented article. The special interest should be devoted to the analysis and in-time prediction of fatal attention decreases and to the design and construction of the respective on-board applicable warning system

    Lay Judgments about Child Custody after Divorce

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    In a pair of studies, we examine lay people’s judgments about how hypothetical cases involving child custody after divorce should be resolved. The respondents were citizens called to jury service in Pima County, Arizona. Study 1 found that both male and female respondents, if they were the judge, would most commonly award equally shared custody arrangements, as advocated by most fathers’ groups. However, if the predivorce child care had been divided disproportionately between the parents, this preference shifted, slightly but significantly, toward giving more time to the parent who had provided most of that care, consistent with the Approximation Rule advocated by the American Law Institute. Moreover, respondents judged that the arrangements prevailing in today’s court and legal environment would award equal custody considerably less often, and would thereby provide much less parenting time to fathers, than the respondents themselves would award. Study 2 found that respondents maintained their strong preference for equally shared custody even when there are very high levels of parental conflict for which the parents were equally to blame, but awarded substantially less time to the culpable parent when only one was the primary instigator of the parental conflict. The striking degree to which the public favors equal custody combined with their view that the current court system under-awards parenting time to fathers could account for past findings that the system is seriously slanted toward mothers, and suggests that family law may have a public relations problem

    Lay Judgments about Child Custody after Divorce

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    In a pair of studies, we examine lay people’s judgments about how hypothetical cases involving child custody after divorce should be resolved. The respondents were citizens called to jury service in Pima County, Arizona. Study 1 found that both male and female respondents, if they were the judge, would most commonly award equally shared custody arrangements, as advocated by most fathers’ groups. However, if the predivorce child care had been divided disproportionately between the parents, this preference shifted, slightly but significantly, toward giving more time to the parent who had provided most of that care, consistent with the Approximation Rule advocated by the American Law Institute. Moreover, respondents judged that the arrangements prevailing in today’s court and legal environment would award equal custody considerably less often, and would thereby provide much less parenting time to fathers, than the respondents themselves would award. Study 2 found that respondents maintained their strong preference for equally shared custody even when there are very high levels of parental conflict for which the parents were equally to blame, but awarded substantially less time to the culpable parent when only one was the primary instigator of the parental conflict. The striking degree to which the public favors equal custody combined with their view that the current court system under-awards parenting time to fathers could account for past findings that the system is seriously slanted toward mothers, and suggests that family law may have a public relations problem

    The spectroscopic evolution of the symbiotic-like recurrent nova V407 Cygni during its 2010 outburst. I. The shock and its evolution

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    On 2010 Mar 10, V407 Cyg was discovered in outburst, eventually reaching V< 8 and detected by Fermi. Using medium and high resolution ground-based optical spectra, visual and Swift UV photometry, and Swift X-ray spectrophotometry, we describe the behavior of the high-velocity profile evolution for this nova during its first three months. The peak of the X-ray emission occurred at about day 40 with a broad maximum and decline after day 50. The main changes in the optical spectrum began at around that time. The He II 4686A line first appeared between days 7 and 14 and initially displayed a broad, symmetric profile that is characteristic of all species before day 60. Low-excitation lines remained comparatively narrow, with v(rad,max) of order 200-400 km/s. They were systematically more symmetric than lines such as [Ca V], [Fe VII], [Fe X], and He II, all of which showed a sequence of profile changes going from symmetric to a blue wing similar to that of the low ionization species but with a red wing extended to as high as 600 km/s . The Na I D doublet developed a broad component with similar velocity width to the other low-ionization species. The O VI Raman features were not detected. We interpret these variations as aspherical expansion of the ejecta within the Mira wind. The blue side is from the shock penetrating into the wind while the red wing is from the low-density periphery. The maximum radial velocities obey power laws, v(rad,max) t^{-n} with n ~ 1/3 for red wing and ~0.8 for the blue. (truncated)Comment: Accepted for publication, A&A (submitted: 9 Oct 2010; accepted: 1 Dec 2010) in press; based on data obtained with Swift, Nordic Optical Telescope, Ondrejov Observatory. Corrected typo, Fermi?LAT detection was at energies above 100 MeV (with thanks to C. C. Cheung

    Moral Intuitions about Fault, Parenting, and Child Custody after Divorce

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    Allocations of child custody postdivorce are currently determined according to the best interest standard; that is, what is best for the child. Decisions about what is best for a child necessarily reflect cultural norms, at least in part. It is therefore useful as well as interesting to ask whether current understandings of the best interest standard align with moral intuitions of lay citizens asked to take the role of judge in hypothetical cases. Do factors such as whether 1 parent had an extramarital affair influence how respondents would award custody? In the current studies, a representative sample of citizens awaiting jury service was first given a neutral scenario portraying an “average” family. Almost 80% favored dividing custodial time equally between the 2 parents, replicating earlier findings. Then, in Study 1, they were given a second, test case, vignette in which either the mother or the father was said to have carried on an extramarital affair that “essentially ruined the marriage.” In Study 2, either the mother or the father was said to have sought the divorce, opposed by the other, simply because he or she “grew tired” of the marriage. For both test cases, our respondents awarded the offending parent significantly less parenting time; about half of our respondents in each Study. The findings indicate that many citizens feel both having an affair and growing tired of the marriage is sufficient cause to award decreased parenting time, reasons for which are explored in the discussion

    Lay Judgments about Child Custody after Divorce

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    In a pair of studies, we examine lay people’s judgments about how hypothetical cases involving child custody after divorce should be resolved. The respondents were citizens called to jury service in Pima County, Arizona. Study 1 found that both male and female respondents, if they were the judge, would most commonly award equally shared custody arrangements, as advocated by most fathers’ groups. However, if the predivorce child care had been divided disproportionately between the parents, this preference shifted, slightly but significantly, toward giving more time to the parent who had provided most of that care, consistent with the Approximation Rule advocated by the American Law Institute. Moreover, respondents judged that the arrangements prevailing in today’s court and legal environment would award equal custody considerably less often, and would thereby provide much less parenting time to fathers, than the respondents themselves would award. Study 2 found that respondents maintained their strong preference for equally shared custody even when there are very high levels of parental conflict for which the parents were equally to blame, but awarded substantially less time to the culpable parent when only one was the primary instigator of the parental conflict. The striking degree to which the public favors equal custody combined with their view that the current court system under-awards parenting time to fathers could account for past findings that the system is seriously slanted toward mothers, and suggests that family law may have a public relations problem

    Lay Judgments about Child Custody after Divorce

    Get PDF
    In a pair of studies, we examine lay people’s judgments about how hypothetical cases involving child custody after divorce should be resolved. The respondents were citizens called to jury service in Pima County, Arizona. Study 1 found that both male and female respondents, if they were the judge, would most commonly award equally shared custody arrangements, as advocated by most fathers’ groups. However, if the predivorce child care had been divided disproportionately between the parents, this preference shifted, slightly but significantly, toward giving more time to the parent who had provided most of that care, consistent with the Approximation Rule advocated by the American Law Institute. Moreover, respondents judged that the arrangements prevailing in today’s court and legal environment would award equal custody considerably less often, and would thereby provide much less parenting time to fathers, than the respondents themselves would award. Study 2 found that respondents maintained their strong preference for equally shared custody even when there are very high levels of parental conflict for which the parents were equally to blame, but awarded substantially less time to the culpable parent when only one was the primary instigator of the parental conflict. The striking degree to which the public favors equal custody combined with their view that the current court system under-awards parenting time to fathers could account for past findings that the system is seriously slanted toward mothers, and suggests that family law may have a public relations problem
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