11,621 research outputs found

    Comments on "There is no axiomatic system for the quantum theory"

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    In a recent paper, Nagata [1] claims to derive inconsistencies from quantum mechanics. In this paper, we show that the inconsistencies do not come from quantum mechanics, but from extra assumptions about the reality of observables

    Beyond the quantum formalism: consequences of a neural-oscillator model to quantum cognition

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    In this paper we present a neural oscillator model of stimulus response theory that exhibits quantum-like behavior. We then show that without adding any additional assumptions, a quantum model constructed to fit observable pairwise correlations has no predictive power over the unknown triple moment, obtainable through the activation of multiple oscillators. We compare this with the results obtained in de Barros (2013), where a criteria of rationality gives optimal ranges for the triple moment.Comment: 4 pages; to appear in the Advances in Cognitive Neurodynamics, Proceedings of the 4th International Conference on Cognitive Neurodynamics - 201

    Comments on the Quantum Potential Approach to a Class of Quantum Cosmological Models

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    In this comment we bring attention to the fact that when we apply the ontological interpretation of quantum mechanics, we must be sure to use it in the coordinate representation. This is particularly important when canonical tranformations that mix momenta and coordinates are present. This implies that some of the results obtained by A. B\l aut and J. Kowalski-Glikman are incorrect.Comment: 7 pages, LaTe

    Assessing satellite-based precipitation estimates in the Southern Appalachian mountains using rain gauges and TRMM PR

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    A study was performed using the first full year of rain gauge records from a newly deployed network in the Southern Appalachian mountains. This is a region characterized by complex topography with orographic rainfall enhancement up to 300% over small distances (<8 km). Rain gauge observations were used to assess precipitation estimates from the Precipitation Radar (PR) on board of the TRMM satellite, specifically the TRMM PR 2A25 precipitation product. Results show substantial differences between annual records and isolated events (e.g. tropical storm Fay). An overall bias of −27% was found between TRMM PR 2A25 rain rate and rain gauge rain rates for the complete one year of study (−59% for tropical storm Fay). Besides differences observed for concurrent observations by the satellite and the rain gauges, a large number of rainfall events is detected independently by either one of the observing systems alone (rain gauges: 50% of events are missed by TRMM PR; TRMM PR: 20% of events are not detected by the rain gauges), especially for light rainfall conditions (0.1–2mm/h) that account for more than 80% of all the missed satellite events. An exploratory investigation using a microphysical model along with TRMM reflectivity factors at selected heights was conducted to determine the shape of the drop size distribution (DSD) that can be applied to reduce the difference between TRMM estimates and rain gauge observations. The results suggest that the critical DSD parameter is the number concentration of very small drops. For tropical storm Fay an increase of one order of magnitude in the number of small drops is apparently needed to capture the observed rainfall rate regardless of the value of the measured reflectivity. This is consistent with DSD observations that report high concentrations of small and/or midsize drops in the case of tropical storms

    Exploring the use of a column model for the characterization of microphysical processes in warm rain: results from a homogeneous rainshaft model

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    International audienceA study of the evolution of raindrop spectra (raindrop size distribution, DSD) between cloud base and the ground surface was conducted using a column model of stochastic coalescense-breakup dynamics. Numerical results show that, under steady-state boundary conditions (i.e. constant rainfall rate and DSD at the top of the rainshaft), the equilibrium DSD is achieved only for high rain rates produced by midlevel or higher clouds and after long simulation times (~30 min or greater). Because these conditions are not typical of most rainfall, the results suggest that the theoretical equilibrium DSD might not be attainable for the duration of individual rain events, and thus DSD observations from field experiments should be analyzed conditional on the specific storm environment under which they were obtained

    Tourism in Azores Islands: Persistence in the Monthly Arrivals

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    This study analyses the persistence in the international monthly arrivals to the Azores Islands using a model based on fractional integration and seasonal autoregressions. The estimated fractional differencing parameter gives an indication of the long run evolution of the series. We use both aggregate data and disaggregate monthly data by location of origin and island destination. The results show that the aggregate series corresponding to the total number of arrivals is a nonstationary I(d) process with d above 1, and the most persistent ones are those travelling to Säo Miguel, especially from Holland, Finland, Norway, Germany, Denmark and the UK.Monthly arrivals; Seasonal fractional integration; Persistence; Azores Islands.

    Persistence on airline accidents

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    This paper analyses airline accidents data from 1927-2006. The fractional integration methodology is adopted. It is shown that airline accidents are persistent and (fractionally) cointegrated with airline traffic. Thus, there exists an equilibrium relation between air accidents and airline traffic, with the effect of the shocks to that relationship disappearing in the long run. Policy implications are derived for countering accidents events.

    Synchronous Endometrioid Endometrial and Ovarian Cancer in a 34-Year-Old Woman

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    Ovarian cancer is the leading cause of death from gynaecological malignancy in developed countries. Synchronous endometrioid endometrial and ovarian cancer in patients appears with different clinical characteristics compared to patients with isolated endometrial cancer. A 34-year-old woman with lower abdominal pain of 1 year duration presented at the emergency department. On gynaecological examination, she had a left and midline pelvic mass. A transvaginal ultrasound showed it to be a complex hypervascularised mass, with cystic and solid components on left adnexal region. Ectopic pregnancy and pelvic inflammatory disease were excluded. Serum levels of tumour marker CA125 and ROMA were increased. The MR showed a complex mass, suggestive of primary fallopian tube or ovarian tumour. The patient underwent a total abdominal hysterectomy, bilateral salpingo-oophorectomy, pelvic and para-aortic lymph node dissection and subcolonic omentectomy. Histopathology revealed a synchronous endometrioid endometrial and ovarian cancer.info:eu-repo/semantics/publishedVersio
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