529 research outputs found
Accuracy Uncomposed: Against Calibrationism
Pettigrew offers new axiomatic constraints on legitimate measures of inaccuracy.
His axiom called ‘Decomposition’ stipulates that legitimate measures of inaccuracy
evaluate a credence function in part based on its level of calibration at a world. I
argue that if calibration is valuable, as Pettigrew claims, then this fact is an explanandum
for accuracy-rst epistemologists, not an explanans, for three reasons. First,
the intuitive case for the importance of calibration isn’t as strong as Pettigrew
believes. Second, calibration is a perniciously global property that both contravenes
Pettigrew’s own views about the nature of credence functions themselves
and undercuts the achievements and ambitions of accuracy-rst epistemology.
Finally, Decomposition introduces a new kind of value compatible with but separate
from accuracy-proper in violation of Pettigrew’s alethic monism.
introductio
Critical Strain Region Evaluation of Self-Assembled Semiconductor Quantum Dots
A novel peak finding method to map the strain from high resolution transmission electron micrographs, known as the Peak Pairs method, has been applied to In(Ga) As/AlGaAs quantum dot (QD) samples, which present stacking faults emerging from the QD edges. Moreover, strain distribution has been simulated by the finite element method applying the elastic theory on a 3D QD model. The agreement existing between determined and simulated strain values reveals that these techniques are consistent enough to qualitatively characterize the strain distribution of nanostructured materials. The correct application of both methods allows the localization of critical strain zones in semiconductor QDs, predicting the nucleation of defects, and being a very useful tool for the design of semiconductor device
Numerical simulation of Ge solar cells using D-AMPS-1D code
A solar cell is a solid state device that converts the energy of sunlight directly into electricity by the photovoltaic effect. When light with photon energies greater than the band gap is absorbed by a semiconductor material, free electrons and free holes are generated by optical excitation in the material. The main characteristic of a photovoltaic device is the presence of internal electric field able to separate the free electrons and holes so they can pass out of the material to the external circuit before they recombine. Numerical simulation of photovoltaic devices plays a crucial role in their design, performance prediction, and comprehension of the fundamental phenomena ruling their operation. The electrical transport and the optical behavior of the solar cells discussed in this work were studied with the simulation code D-AMPS-1D. This software is an updated version of the one-dimensional (1D) simulation program Analysis of Microelectronic and Photonic Devices (AMPS) that was initially developed at The Penn State University, USA. Structures such as homojunctions, heterojunctions, multijunctions, etc., resulting from stacking layers of different materials can be studied by appropriately selecting characteristic parameters. In this work, examples of cells simulation made with D-AMPS-1D are shown. Particularly, results of Ge photovoltaic devices are presented. The role of the InGaP buffer on the device was studied. Moreover, a comparison of the simulated electrical parameters with experimental results was performed
Model for Anisotropic Directed Percolation
We propose a simulation model to study the properties of directed percolation
in two-dimensional (2D) anisotropic random media. The degree of anisotropy in
the model is given by the ratio between the axes of a semi-ellipse
enclosing the bonds that promote percolation in one direction. At percolation,
this simple model shows that the average number of bonds per site in 2D is an
invariant equal to 2.8 independently of . This result suggests that
Sinai's theorem proposed originally for isotropic percolation is also valid for
anisotropic directed percolation problems. The new invariant also yields a
constant fractal dimension for all , which is the same
value found in isotropic directed percolation (i.e., ).Comment: RevTeX, 9 pages, 3 figures. To appear in Phys.Rev.
Conductivity Exponent and Backbone Dimension in 2-d Percolation
We present high statistics simulations for 2-d percolation clusters in the
"bus bar" geometry at the critical point, for site and for bond percolation. We
measured their backbone sizes and electrical conductivities. For all sets of
measurements we find large corrections to scaling, most of which do not seem to
be described by single powers. Using single power terms for the corrections to
scaling of the backbone masses, we would obtain fractal dimensions which are
different for site and bond percolation, while the correct result is for both. For the conductivity, the corrections to scaling are
strongly non-monotonic for bond percolation. The exponent is
measured as 0.9826(8), in disagreement with the Alexander-Orbach and other
conjectures.Comment: 15 pages, including 5 figures and 2 tables; minor change
Paternity and Legal Abortion: A Comprehensive Analysis of Rights, Responsibilities and Social Impact
Introduction: the abortion debate in society revolves around women\u27s reproductive rights and autonomy, while also considering men\u27s perspectives and societal implications. Women argue for the right to make decisions about their bodies, emphasizing the potential consequences of denying this right, such as forced motherhood and restricted personal and professional development. Men, too, play a role in the debate, with some supporting women\u27s rights and emphasizing the importance of joint decision-making in relationships. Development: the historical context of abortion is complex, with different societies and time periods featuring varying views and regulations. From ancient civilizations to modern eras, practices and legal approaches to abortion have evolved. In the Middle Ages, the Catholic Church had a significant impact on abortion regulation, while scientific and medical advancements shaped modern debates. Abortion is defined as the deliberate termination of pregnancy before fetal viability, with legal definitions varying worldwide. Understanding these distinctions is essential to address abortion comprehensively. In Argentina, the historic reform of 2020 marked a significant change in abortion legislation, permitting termination of pregnancy up to 14 weeks without justification. The feminist movement played a crucial role in advocating for this reform, leading to a more inclusive and equitable approach. Despite this progress, challenges remain, including ensuring nationwide access and promoting comprehensive sexual education. Responsible fatherhood involves recognizing men\u27s rights and responsibilities in pregnancy and abortion. Men have the right to receive information, be present during pregnancy and childbirth, and establish custody and visitation arrangements. Emotional support, financial contributions, and active participation in decision-making are also essential aspects. Legislation regarding men\u27s involvement in abortion decisions varies, but a balanced, informed dialogue is encouraged.Conclusions: Argentina\u27s legalization of abortion represents a significant step forward for women\u27s reproductive rights and autonomy. The Law on the Voluntary Interruption of Pregnancy recognizes fundamental rights and guarantees and establishes access to safe and legal abortion services. However, challenges persist in ensuring equal access across the country. Responsible fatherhood involves recognizing men\u27s rights and responsibilities in pregnancy and abortion decision
Influence of Annealing on the Optical and Scintillation Properties of CaWO Single Crystals
We investigate the influence of oxygen annealing on the room temperature
optical and scintillation properties of CaWO single crystals that are being
produced for direct Dark Matter search experiments. The applied annealing
procedure reduces the absorption coefficient at the peak position of the
scintillation spectrum ( nm) by a factor of and leads to an
even larger reduction of the scattering coefficient. Furthermore, the annealing
has no significant influence on the \emph{intrinsic} light yield. An additional
absorption occurring at nm suggests the formation of O hole
centers. Light-yield measurements at room temperature where one crystal surface
was mechanically roughened showed an increase of the \emph{measured} light
yield by and an improvement of the energy resolution at 59.5 keV by
for the annealed crystal. We ascribe this result to the reduction of
the absorption coefficient while the surface roughening is needed to compensate
for the also observed reduction of the scattering coefficient after annealing
- …
