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Search Results: 1 - 10 of 464011 matches for " Monika; García "
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Application of Learning Curves for Didactic Model Evaluation: Case Studies
Felix M?dritscher,Monika Andergassen,Effie Lai-Chong Law,Victor Manuel García-Barrios
International Journal of Emerging Technologies in Learning (iJET) , 2013, DOI: 10.3991/ijet.v8is1.2357
Abstract: The success of (online) courses depends, among other factors, on the underlying didactical models which have always been evaluated with qualitative and quantitative research methods. Several new evaluation techniques have been developed and established in the last years. One of them is ‘learning curves’, which aim at measuring error rates of users when they interact with adaptive educational systems, thereby enabling the underlying models to be evaluated and improved. In this paper, we report how we have applied this new method to two case studies to show that learning curves are useful to evaluate didactical models and their implementation in educational platforms. Results show that the error rates follow a power law distribution with each additional attempt if the didactical model of an instructional unit is valid. Furthermore, the initial error rate, the slope of the curve and the goodness of fit of the curve are valid indicators for the difficulty level of a course and the quality of its didactical model. As a conclusion, the idea of applying learning curves for evaluating didactical model on the basis of usage data is considered to be valuable for supporting teachers and learning content providers in improving their online courses.
Nuevas alternativas para la analgesia perioperatoria en cirugia cardiovascular: antecedentes
Agüero Martínez,Maria Oslaida; Jiménez Peneque,Rosa; Cruz Bouza,Raúl; Nodal Leyva,Pedro; Pérez Rodriguez,Monika; García,Raúl;
Revista Cubana de Anestesiolog?-a y Reanimaci?3n , 2009,
Abstract: like anesthesiologists and out of a sense of duty, we must to provide to our patients of a appropriate perioperative analgesia and to inhibit the organic response to surgical anesthetic stress. in cardiovascular surgery this response comes from two fundamental facts: tissue traumatism and extracorporeal circulation. aims: to explain the main causes for its control. development: many have been the techniques used to pain control in search of a better option. in last years the use of anesthesia-analgesia techniques (epidural and intrathecal) has increased, despite the present controversies, the benefits related to both are superior to reported risks. conclusions: anesthesia quality with spinal anesthetic methods has been valid in cardiovascular surgery to achieve a fast recovery of patient and its incorporation into family and working life.
Economic Evaluation of Early Peach (Prunus Persica L. batsch) Commercial Orchard under Different Irrigation Strategies  [PDF]
Jesus García García, Jose García Brunton
Open Journal of Accounting (OJAcct) , 2013, DOI: 10.4236/ojacct.2013.24014
Abstract: The main aim of this paper is to evaluate the economic response of different irrigation water levels in an early ripening peach variety. In this sense, we evaluate the economics and overall water use efficiency. The test is designed with 4 irrigation water strategies. The economic indices used that use net margin show that all the alternatives are viable although the control with its Net Margin (NM)/Cost (C) of 23.6% is of particular note. This is followed by R50, the highest deficit treatment, with an
NM/C of 16.0%. The mean production cost was almost identical in the optimal treatment (control) and the R50 deficit treatment, €0.69 and €0.70, respectively.
R50 was the most efficient treatment, with a Water Use Efficiency (WUE) of 5.54 kg·m-3. The NM m-3 as economic efficiency index was the greatest in the control (0.74 € m-3), followed by R50 (0.65 € m-3), while the other treatments were far from these figures. Peach cultivation generates a lot of employment and in all cases the Number of Agricultural Jobs (NAJ) ha-1 was around 0.59. As regards the social efficiency of water, the deficit treatments we applied reached high values in this respect, reaching 181 NAJ hm-3 in R50.

Inhibiting Effect of Tetra-n-Butylammonium Iodide on the Corrosion of Mild Steel in Acidic Medium
,Monika; Siddique,W.A.;
Portugaliae Electrochimica Acta , 2007,
Abstract: the inhibition effect of tetra-n-butylammonium iodide (tbai) on mild steel in 1 n h2so4 has been studied by using weight loss, electrochemical polarization, fourier transform infrared (ftir) and scanning electron microscopic (sem) techniques. it has been concluded that the percentage inhibition increases with increasing the concentration of the inhibitor. the adsorption of tbai on mild steel surface in 1 n h2so4 obeys langmuir adsorption isotherm; surface analysis and ir studies are also carried out to establish the mechanism of corrosion inhibition.
Inhibiting Effect of Tetra-n-Butylammonium Iodide on the Corrosion of Mild Steel in Acidic Medium
Monika,W.A. Siddique
Portugaliae Electrochimica Acta , 2007,
Abstract: The inhibition effect of tetra-N-butylammonium iodide (TBAI) on mild steel in 1 N H2SO4 has been studied by using weight loss, electrochemical polarization, Fourier Transform Infrared (FTIR) and scanning electron microscopic (SEM) techniques. It has been concluded that the percentage inhibition increases with increasing the concentration of the inhibitor. The adsorption of TBAI on mild steel surface in 1 N H2SO4 obeys Langmuir adsorption isotherm; surface analysis and IR studies are also carried out to establish the mechanism of corrosion inhibition.
Synthesis, Structural, and Biological Studies of Some Schiff Bases and Their Metal Complexes
A. P. Mishra,Monika Soni
Metal-Based Drugs , 2008, DOI: 10.1155/2008/875410
Abstract: New bidentate or tridentate Schiff bases and their VO(II) and Co(II) complexes formed by the condensation of methyl isobutyl ketone with nicotinamide (mna)/2-amino-4-chlorophenol (map) and 2-hydroxy acetophenone with nicotinamide (han)/isoniazide (hai). Physicochemical characterization has been carried out to determine the structure of the complexes. The FAB mass and thermal data show degradation pattern of the complexes. XRD analysis reveals that all the studied complexes crystallize as tetragonal crystal system. Some of the complexes have been screened for their antimicrobial activity by the well diffusion technique using DMSO as solvent on different species of pathogenic bacteria/fungi, that is, E. coli, S. aureus, S. fecalis, A. niger, T. polysporum, and their antimicrobial potency have been discussed. It has been found that all the complexes are antimicrobially active and show higher activity than the free ligand. Metal chelation affects significantly the antimicrobial/bioactive behavior of the organic ligands.
Journey from the Heart of Darkness to the Heart of Sadness: Fiction v/s Reality
Yousof A. Qasaimeh,Monika Joshi
International Journal of Psychological Studies , 2009, DOI: 10.5539/ijps.v1n1p42
Abstract: The purpose of this study is to perceive the give – and – take between art and real life conditions. It presents information on the writing of the novel Heart of Darkness by Joseph Conrad whose continental experience and familiarity with the imperial milieu in the east and Africa rendered him capable of bringing much greater knowledge of real politic into literary work more than any one else. It seems fruitful to see how the authors deal with the gap between how things could or should be in a given society, and how they really are. International politics is devoid of moral values as can be seen in the case of Congo in Heart of Darkness (a fictional situation) and in the present Iraqi situation (a real- life situation). In Heart of Darkness there is a suggestion that the exploited will some day, sooner or later, rise in revolt against the exploitation of the foreign rule. Can oppressed nations like Congo and Iraq hope to conclude this tiresome journey in the near future and set out a fresh on new journey, perhaps one into the Heart of Happiness? The answer to this question remains unknown at the present time. In spite of this, people of these nations should be optimize, keeping in mind that it is always darkest before the dawn, and that Stars shine out the most brilliantly through dark clouds.
Methods for the Study of Transverse Momentum Differential Correlations
Monika Sharma,Claude A. Pruneau
Physics , 2008, DOI: 10.1103/PhysRevC.79.024905
Abstract: We introduce and compare three differential correlation functions for the study of transverse momentum correlation in $p+p$ and $A+A$ collisions. These consist of {\it inclusive}, {\it event-wise} and a differential version of the correlation measure $\tilde C$ introduced by Gavin \cite{Gavin} for experimental study of the viscosity per unit entropy of the matter produced in $A+A$ collisions. We study the quantitative difference between the three observables on the basis of PYTHIA simulations of $p+p$ collisions and $A+A$ collisions consisting of an arbitrary superposition of $p+p$ collision events at $\sqrt{s} = $200 GeV. We observe that {\it inclusive} and {\it event-wise} correlation functions are remarkably identical to each other where as the observable $\tilde C$ differs from the two. We study the robustness and efficiency dependencies of these observables based on truncated Taylor expansions in efficiency in $p+p$ collisions and on the basis of Monte Carlo simulation using an adhoc detector efficiency parameterization. We find that all the three observables are essentially independent of detector efficiency. We additionally study the scaling of the correlation measures and find all the observables exhibit an approximate $1/N$ dependence of the number of participants ({\it N}) in $A+A$ collisions. Finally, we study the impact of flow-like anisotropy on the {\it inclusive} correlation function and find flow imparts azimuthal modulations similar to those observed with two-particle densities.
The Effect of Different Movement Exercises on Cognitive and Motor Abilities  [PDF]
Monika Thomas
Advances in Physical Education (APE) , 2012, DOI: 10.4236/ape.2012.24030
Abstract: The influence of physical activity on motor and cognitive performance has been approved in several studies. However, it is still unclear which functions are affected, and why. It also remains unknown what type of physical training is best suitable. The present study focuses on special movement aspects based on the Brain Gym? program. Four groups of subjects (n = 64) participated in two experiments with pre-post intervention design. In experiment 1 two groups of subjects were exposed to a sensorimotor adaptation study design by executing center out pointing movements under distorted visual feedback conditions with their dominant and non-dominant arm to test for intermanual transfer (IMT) as pre- and posttest. The intervention in both groups consisted of specified movement exercises with the right and left extremities: participants of Experimental group executed movements crossing the body midline and participants of Control group movements without crossing the body midline. Results showed a decreased retention of adaptation but larger IMT for Experimental group during posttest. We conclude that movements crossing the body midline impede retention but enhance IMT of sensorimotor adaptation. A potential relationship to an improvement of communication between the cerebral hemispheres evoked by the movement exercises crossing the body midline is rather speculative. In experiment 2 two groups were exposed to the d2-test measuring concentration and attention and a dice-test testing for visual-spatial abilities as pre- and posttest. The interventions were similar to experiment 1. Results yielded no differences between groups such that different effects of both interventions could not have been shown.
Two Blind Adaptive Equalizers Connected in Series for Equalization Performance Improvement  [PDF]
Monika Pinchas
Journal of Signal and Information Processing (JSIP) , 2013, DOI: 10.4236/jsip.2013.41008
Abstract:

A variable step-size parameter is usually used to accelerate the convergence speed of a blind adaptive equalizer with N1 + N2 -1 coefficients where N1 and N2 are odd values. In this paper we show that improved equalization performance is achieved when using two blind adaptive equalizers connected in series where the first and second blind adaptive equalizer have N1 and N2 coefficients respectively compared with the case where a single blind adaptive equalizer is applied with N1 + N2 -1 coefficients. It should be pointed out that the same algorithm (cost function) is used for updating the filter taps for the different equalizers and that a fixed step-size parameter is used. Simulation results show that for the low signal to noise ratio (SNR) environment and for the case where the convergence speed is slow due to the channel characteristics, the new method has a faster convergence speed with a factor of approximately two while leaving the system with approximately the same or lower residual intersymbol interference (ISI).

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