8,117 research outputs found
Decision Making for Inconsistent Expert Judgments Using Negative Probabilities
In this paper we provide a simple random-variable example of inconsistent
information, and analyze it using three different approaches: Bayesian,
quantum-like, and negative probabilities. We then show that, at least for this
particular example, both the Bayesian and the quantum-like approaches have less
normative power than the negative probabilities one.Comment: 14 pages, revised version to appear in the Proceedings of the QI2013
(Quantum Interactions) conferenc
Intense CIII] 1907,1909 emission from a strong Lyman continuum emitting galaxy
We have obtained the first complete ultraviolet (UV) spectrum of a strong
Lyman continuum(LyC) emitter at low redshift -- the compact, low-metallicity,
star-forming galaxy J1154+2443 -- with a Lyman continuum escape fraction of 46%
discovered recently. The Space Telescope Imaging Spectrograph spectrum shows
strong Lya and CIII] 1909 emission, as well as OIII] 1666. Our observations
show that strong LyC emitters can have UV emission lines with a high equivalent
width (e.g. EW(CIII]) rest-frame), although their equivalent
widths should be reduced due to the loss of ionizing photons. The intrinsic
ionizing photon production efficiency of J1154+2443 is high, erg Hz, comparable to that of other recently discovered
LyC emitters. Combining our measurements and earlier
determinations from the literature, we find a trend of increasing with increasing CIII] 1909 equivalent width, which can be understood by
a combination of decreasing stellar population age and metallicity. Simple
ionization and density-bounded photoionization models can explain the main
observational features including the UV spectrum of J1154+2443.Comment: 5 pages, 4 figures. Accepted for publication in A&A Letter
Approaching equilibrium and the distribution of clusters
We investigate the approach to stable and metastable equilibrium in Ising
models using a cluster representation. The distribution of nucleation times is
determined using the Metropolis algorithm and the corresponding
model using Langevin dynamics. We find that the nucleation rate is suppressed
at early times even after global variables such as the magnetization and energy
have apparently reached their time independent values. The mean number of
clusters whose size is comparable to the size of the nucleating droplet becomes
time independent at about the same time that the nucleation rate reaches its
constant value. We also find subtle structural differences between the
nucleating droplets formed before and after apparent metastable equilibrium has
been established.Comment: 22 pages, 16 figure
The GREATS H+[OIII] Luminosity Function and Galaxy Properties at : Walking the Way of JWST
The James Webb Space Telescope will allow to spectroscopically study an
unprecedented number of galaxies deep into the reionization era, notably by
detecting [OIII] and H nebular emission lines. To efficiently prepare
such observations, we photometrically select a large sample of galaxies at
and study their rest-frame optical emission lines. Combining data from
the GOODS Re-ionization Era wide-Area Treasury from Spitzer (GREATS) survey and
from HST, we perform spectral energy distribution (SED) fitting, using
synthetic SEDs from a large grid of photoionization models. The deep
Spitzer/IRAC data combined with our models exploring a large parameter space
enables to constrain the [OIII]+H fluxes and equivalent widths for our
sample, as well as the average physical properties of galaxies, such
as the ionizing photon production efficiency with
. We
find a relatively tight correlation between the [OIII]+H and UV
luminosity, which we use to derive for the first time the [OIII]+H
luminosity function (LF) at . The [OIII]+H LF is higher
at all luminosities compared to lower redshift, as opposed to the UV LF, due to
an increase of the [OIII]+H luminosity at a given UV luminosity from
to . Finally, using the [OIII]+H LF, we make
predictions for JWST/NIRSpec number counts of galaxies. We find that
the current wide-area extragalactic legacy fields are too shallow to use JWST
at maximal efficiency for spectroscopy even at 1hr depth and JWST
pre-imaging to mag will be required.Comment: 13 pages, 9 figures, accepted for publication in MNRA
Economic Feasibility Study of Photovoltaic Panels Installation by PVsyst 6.73 Simulator
The increasing pursuit of industry modernization presenting efficiency gains, productivity and cost reduction raises the discussion about the use of new technologies that promote, simultaneously, business sustainability and productive and economic efficiency for offshore companies, which operates in the Campos Basin, located at the municipality of Macaé, Rio de Janeiro State, Brazil. This paper presents an economic feasibility evaluation to use photovoltaic panels in order to measure the project costs and highlight its benefits; to this end, a local supplier was contacted to estimate a budget. The author ran the PVsyst 6.73 simulator to calculate the energy produced by the photovoltaic system and other parameters. Taking into account the Minimum Attractive Rate (MAR) of 8,3 percent, established by the board of directors, the results, by the Simple Payback and Discounted Payback (SPDP); Profitability Index (PI); Return on Investment (ROI); Net Present Value (NPV); and Internal Rate of Return (IRR) methods applied, proved the project is economically feasible and that this company has physical structure to install the equipment. As such, it is possible to have a great medium-and long-term financial economy, contributing to produce clean energy in the country
Efeito das temperaturas e substratos sobre a germinação de Parkia gigantocarpa Ducke (Leguminosae-Mimosoideae).
Parkia gigantocarpa Ducke, conhecida popularmente como Fava- Atanã é uma espécie de grande porte, que pode ser utilizada para produção de celulose, recomposição de áreas degradadas e construção em geral. O objetivo desse estudo foi verificar a influência de diferentes substratos e temperaturas sobre a germinação de sementes de P. gigantocarpa. Realizou-se um experimento inteiramente casualizado em esquema fatorial 5 x 5, com 4 repetições de 25 sementes, por um período de 12 dias. Foram utilizados diferentes substratos (rolo de papel, areia, areia + serragem (1:1), vermiculita e fibra de coco triturada) em função de diferentes temperaturas constantes (15, 20, 25, 30 e 35ºC). Nas temperaturas de 15 e 20ºC houve inibição no desenvolvimento normal das plântulas, ocorrendo germinação de plântulas normais somente nas temperaturas de 25, 30 e 35°C. No geral, a temperatura de 30°C foi a mais favorável para a germinação das sementes de P. gigantocarpa, tendo como melhores substratos a areia, areia + serragem (1:1) e fibra de coco
Eigenlogic: a Quantum View for Multiple-Valued and Fuzzy Systems
We propose a matrix model for two- and many-valued logic using families of
observables in Hilbert space, the eigenvalues give the truth values of logical
propositions where the atomic input proposition cases are represented by the
respective eigenvectors. For binary logic using the truth values {0,1} logical
observables are pairwise commuting projectors. For the truth values {+1,-1} the
operator system is formally equivalent to that of a composite spin 1/2 system,
the logical observables being isometries belonging to the Pauli group. Also in
this approach fuzzy logic arises naturally when considering non-eigenvectors.
The fuzzy membership function is obtained by the quantum mean value of the
logical projector observable and turns out to be a probability measure in
agreement with recent quantum cognition models. The analogy of many-valued
logic with quantum angular momentum is then established. Logical observables
for three-value logic are formulated as functions of the Lz observable of the
orbital angular momentum l=1. The representative 3-valued 2-argument logical
observables for the Min and Max connectives are explicitly obtained.Comment: 11 pages, 2 table
- …