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The Grand Challenge of Carbon Sequestration
This paper won a third place writing flag award in the collaborative category. Clayton Lawrence, Thomas Nguyen, Mitchell Tomazin, and Norberto Martinez, writing for Brandi DeMont 's ASE 333T class, " Engineering Communication ".DeMont, BrandiUndergraduate Studie
Recommending Learning Algorithms and Their Associated Hyperparameters
The success of machine learning on a given task dependson, among other
things, which learning algorithm is selected and its associated
hyperparameters. Selecting an appropriate learning algorithm and setting its
hyperparameters for a given data set can be a challenging task, especially for
users who are not experts in machine learning. Previous work has examined using
meta-features to predict which learning algorithm and hyperparameters should be
used. However, choosing a set of meta-features that are predictive of algorithm
performance is difficult. Here, we propose to apply collaborative filtering
techniques to learning algorithm and hyperparameter selection, and find that
doing so avoids determining which meta-features to use and outperforms
traditional meta-learning approaches in many cases.Comment: Short paper--2 pages, 2 table
Spontaneous PT symmetry breaking of a ferromagnetic superfluid in a gradient field
We consider the interaction of a ferromagnetic spinor Bose-Einstein
condensate with a magnetic field gradient. The magnetic field gradient realizes
a spin-position coupling that explicitly breaks time-reversal symmetry T and
space parity P, but preserves the combined PT symmetry. We observe using
numerical simulations, a first-order phase transition spontaneously breaking
this re-maining symmetry. The transition to a low-gradient phase, in which
gradient effects are frozen out by the ferromagnetic interaction, suggests the
possibility of high-coherence magnetic sensors unaffected by gradient
dephasing
Paper-based standard addition assays
Standard addition assays conducted on paper-based microfluidic devices are introduced as an alternative to external standards for calibrating quantitative tests. To demonstrate this technique, a colorimetric, paper-based, standard addition assay was optimized for the determination of glucose concentrations in the range of 0 to 5 mM. Comparable results were obtained from the assay via digital image colorimetry under three different lighting conditions
Poly(N-isopropylacrylamide) hydrogels for storage and delivery of reagents to paper-based analytical devices
The thermally responsive hydrogel N,N\u27-methylenebisacrylamide-cross-linked poly(N-isopropylacrylamide) (PNIPAM) was developed and evaluated as a reagent storage and delivery system for microfluidic paper-based analytical devices (microPADs). PNIPAM was shown to successfully deliver multiple solutions to microPADs in specific sequences or simultaneously in laminar-flow configuration and was found to be suitable for delivering four classes of reagents to the devices: Small molecules, enzymes, antibodies and DNA. PNIPAM was also able to successfully deliver a series of standard glucose solutions to microPADs equipped to perform a colorimetric glucose assay. The results of these tests were used to produce an external calibration curve, which in turn was used to determine the concentration of glucose in sample solutions. Finally, PNIPAM was used to store the enzyme horseradish peroxidase for 35 days under ambient conditions with no significant loss of activity. The combination of PNIPAM and microPADs may allow for more complex assays to be performed on paper-based devices, facilitate the preparation of external calibration curves in the field, and extend the shelf life of microPADs by stabilizing reagents in an easy-to-use format
Long-term laser frequency stabilization using fiber interferometers
We report long-term laser frequency stabilization using only the target laser
and a pair of 5 m fiber interferometers, one as a frequency reference and the
second as a sensitive thermometer to stabilize the frequency reference. When
used to stabilize a distributed feedback laser at 795 nm, the frequency Allan
deviation at 1000 s drops from 5.6*10^{-8} to 6.9*10^{-10}. The performance
equals that of an offset lock employing a second, atom-stabilized laser in the
temperature control
El desempeño docente y la competencia investigativa, según los estudiantes de MaestrÃa en Educación de la Escuela de Posgrado de la UNMSM, UNE y UCV, 2012
Determina la relación existente entre el desempeño docente y la competencia investigativa, según los estudiantes de MaestrÃa en Educación de la Escuela de Posgrado de la UNMSM, UNE y UCV en el año 2012. Desarrolla una investigación de tipo descriptivo correlacional y de corte trasversal. Aplica el método cuantitativo positivista. La muestra representativa es de 198 estudiantes obtenida por muestreo aleatorio simple. Luego se repartió esta cantidad mediante fijación proporcional: 94 de la UNMSM, 86 de la UNE y 18 de la UCV. En este último se pudo encuestar a 6 personas más por lo que finalmente se contó con 24 estudiantes de la UCV y una muestra final de 204 estudiantes de maestrÃa. Encuentra que existe evidencia estadÃstica suficiente para afirmar con un nivel de significancia del 5% que el desempeño docente se relaciona con la competencia investigativa, con un 95% de confianza que la responsabilidad se relaciona con la competencia investigativa, con un 5% de significancia que el dominio cientÃfico – tecnológico se relaciona con la competencia investigativa, y con un 95% de confianza que la relaciones interpersonales y formación en valores éticos se relaciona con la competencia investigativa según los estudiantes de MaestrÃa en Educación de la UNE - UNMSM - UCV.Tesi
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