1,024 research outputs found
Neural nets on the MPP
The Massively Parallel Processor (MPP) is an ideal machine for computer experiments with simulated neural nets as well as more general cellular automata. Experiments using the MPP with a formal model neural network are described. The results on problem mapping and computational efficiency apply equally well to the neural nets of Hopfield, Hinton et al., and Geman and Geman
Laboratorios matemáticos para la enseñanza desarrolladora del componente numérico variacional en los estudiantes del grado quinto
Este estudio tiene como objetivo diseñar una estrategia didáctica basada en laboratorios matemáticos para la enseñanza desarrolladora del componente numérico variacional en el grado quinto de la básica primaria de la IE Integrado Carrasquilla Industrial, de tal manera que los docentes dinamicen su quehacer educativo y tengan otra forma de llevar esos contenidos a sus estudiantes, en donde ellos se entusiasmen o se motiven para aprender. Está basado en una metodología descriptiva con enfoque cualitativo y cuantitativo, a través de la experimentación con materiales manipulativos. Como resultado se destacan las dificultades existentes en el componente numérico variacional en el 62% de los estudiantes, lo que deja ver la problemática de estudio y que el 58% se queja de la falta de materiales didácticos en las clases por parte de los docentes; esto muestra que para enseñar matemáticas es necesario un ambiente agradable en aula. Se concluye la importancia de la utilización de materiales manipulativos en el aula a través de la enseñanza desarrolladora y volver al estudiante en el protagonista de su conocimiento
A method for predicting full scale buffet response with rigid wind tunnel model fluctuating pressure data. Volume 1: Prediction method development and assessment
The method requires unsteady aerodynamic forces, natural airplane modes, and the measured pressure data as input. A gust response computer program is used to calculate buffet response due to the forcing function posed by the measured pressure data. By calculating both symmetric and antisymmetric solutions, upper and lower bounds on full-scale buffet response are formed. Comparisons of predictions with flight test results are made and the effects of horizontal tail loads and static aeroelasticity are shown. Discussions are also presented on the effects of primary wing torsion modes, chordwise and spanwise phase angles, and altitude
Molecular evidence for Anaplasma phagocytophilum in Israel
Sequences from the Anaplasma phagocytophilum 16S rRNA gene were detected in 5 ticks representing 3 species (Hyalomma marginatum, Rhipicephalus turanicus, and Boophilus kohlsi) collected from roe deer (Capreolus capreolus) in Mount Carmel, Israel. The sequences were all identical to those of Ap-variant 1 strain
Láser y luz pulsada intensa en el tratamiento de hemangiomas infantiles y malformaciones vasculares
The use of the indications of the laser in treating
vascular malformations and infantile haemangiomas is
based on the theory of selective photothermolysis, in
which the oxyhaemoglobin is the target chromophore
on which the light of the laser acts, thus avoiding damage
to neighbouring tissues. The pulsed dye laser is the
most employed and at present is the treatment of
choice in capillary malformations (port-wine stains). A
variable response is obtained, with a substantial clearing
of the colour of the lesion after several sessions.
Application at early ages seems to improve the results.
Venous malformations, especially those localised in
the mucosa, respond better to the Nd:YAG laser; lymphatic
malformations to the CO2 laser. Arteriovenous
malformations rarely respond. Use of the pulsed dye
laser in the phase of proliferation of the haemangiomas
is subject to controversy, except where there is ulceration.
A rapid re-epithelialization is obtained in these
cases following its use. In the involution phase,
patients with residual vascular lesions can benefit from
other lasers such as KTP or Nd:YAG. If they show an
atrophic surface and scars these complications
improve with the CO2 laser or Er:YAG. New treatment
modalities are emerging, such as photodynamic therapy,
whose efficacy and safety, both in the treatment of
haemangiomas and vascular malformations, have yet
to be confirmed
High Precision Measurements Using High Frequency Signals
Generalized lock-in amplifiers use digital cavities with Q-factors as high as
5X10^8. In this letter, we show that generalized lock-in amplifiers can be used
to analyze microwave (giga-hertz) signals with a precision of few tens of
hertz. We propose that the physical changes in the medium of propagation can be
measured precisely by the ultra-high precision measurement of the signal. We
provide evidence to our proposition by verifying the Newton's law of cooling by
measuring the effect of change in temperature on the phase and amplitude of the
signals propagating through two calibrated cables. The technique could be used
to precisely measure different physical properties of the propagation medium,
for example length, resistance, etc. Real time implementation of the technique
can open up new methodologies of in-situ virtual metrology in material design
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