There is a need to develop spoken dialog systems, such as chatbots, which are capable of engaging in natural conversations with people, especially the socially isolated elderly. We propose an example-based dialog system featuring an... more
There is a need to develop spoken dialog systems, such as chatbots, which are capable of engaging in natural conversations with people, especially the socially isolated elderly. We propose an example-based dialog system featuring an adaptation method which customizes the dialog for each user. After retrieving profile information about the user from the Web, morpheme analysis is applied to the retrieval results and only nouns and proper nouns are extracted. Those which appear with high frequency are considered to be related to the user. We then calculate the similarity between the selected words related to the user and words in the existing example phrases of the dialog system. Cosine similarity between the distributed representations of the nouns is calculated using the word2vec program. We then generate phrases adapted to the user by substituting user-related words for highly similar words in the original example phrases. We manually evaluated the naturalness of the generated phrases and found that the system could generate natural-sounding phrases. Word2vec has a special property which allows arithmetic operations such as plus and minus to be applied to distributed word representations. Using this feature, we were able to derive replacement of words for the example phrases by applying operations to the words used in the original phrases, improving the success rate for generating natural-sounding phrases.
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Gillespie syndrome (GS) [MIM: 206700] is a very rare condition characterized by bilateral iris defect, congenital hypotonia, cerebellar ataxia and intellectual disability. The typical iris anomaly is considered necessary to the diagnosis... more
Gillespie syndrome (GS) [MIM: 206700] is a very rare condition characterized by bilateral iris defect, congenital hypotonia, cerebellar ataxia and intellectual disability. The typical iris anomaly is considered necessary to the diagnosis of GS. Recently, variants in ITPR1 were described causing GS. Non-neurological features were reported in few patients. Here we describe two consanguineous siblings with GS and a novel homozygous ITPR1 pathogenic variant (p.N984fs). They also present a cardiac defect (pulmonary valve stenosis) and one sib had a genitourinary malformation (ureteropelvic junction obstruction). Our report reinforces ITPR1 as the cause of GS and suggests a possible role of ITPR1 in the development of other organs.
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ABSTRACT
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Recently there is an increased interest in developing magnetic semiconductors due to their promising applications in spintronics. The semiconductors can be made ferromagnetic by doping with transition-metal ions. In this paper, the... more
Recently there is an increased interest in developing magnetic semiconductors due to their promising applications in spintronics. The semiconductors can be made ferromagnetic by doping with transition-metal ions. In this paper, the results of our studies using x-ray diffraction (XRD) and IR and Raman spectroscopic techniques on the effect of Fe doping on the structural properties of SnO2 are presented.
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ABSTRACT NiO–SiO2 nanocomposite thin films were prepared by sol–gel technique. The formed films gels were calcined at 200, 400, 600, 800 and 1100 °C for 4 h leading to NiO–SiO2 nanocomposites. For these films, the X-ray diffraction, the... more
ABSTRACT NiO–SiO2 nanocomposite thin films were prepared by sol–gel technique. The formed films gels were calcined at 200, 400, 600, 800 and 1100 °C for 4 h leading to NiO–SiO2 nanocomposites. For these films, the X-ray diffraction, the Fourier transform infrared absorption and the field emission scanning electron microscopy were investigated. Our results show that the NiO(2 0 0) diffraction peak dominates in the preset work. NiO phase appeared in the XRD patterns for all samples. The newly prepared photocatalysts films have been evaluated by the determination of their photonic efficiencies for degradation of methylene. The results reveal that the photonic efficiency increases with increasing calcination temperature up to 600 °C with the maximum photonic efficiency being 0.62%. In addition, porous structures were observed and improve the sensitivity of these nanocomposites for gas sensing.
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Se describe el análisis de factibilidad técnica y económica del secado solar de café pergamino en plazoletas de hormigón ennegrecidas. Se presenta de forma comparativa el estudio de la cinética del secado y la valoración económica del... more
Se describe el análisis de factibilidad técnica y económica del secado solar de café pergamino en plazoletas de hormigón ennegrecidas. Se presenta de forma comparativa el estudio de la cinética del secado y la valoración económica del efecto de la plazoleta ennegrecida, la ...
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Nano-structured hydrotalcite based mixed oxides have been synthesized using coprecipitation method under variable pH and low supersaturation condition. XRD technique has been used to confirm the hydrotalcite structure and its derived... more
Nano-structured hydrotalcite based mixed oxides have been synthesized using coprecipitation method under variable pH and low supersaturation condition. XRD technique has been used to confirm the hydrotalcite structure and its derived different phase of mixed oxides. The metal dispersion of mixed oxides was analyzed using ICP-MS. The nanostructures of the mixed oxides have been investigated using FESEM and HRTEM. The textural properties of mixed oxides were analyzed using N2 adsorption-desorption (BET) technique. The Characterizations have revealed that the developed mixed oxides were consisted with hexagonal/rhombohedral well dispersed nano-particles. Polycrystalline mixed oxides formed mesopore surface and narrower pore size distribution.
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... El resultado del análisis muestra una distribución favorable de las áreas de captación y de pérdidas, por lo que es posible pronosticar un buen funcionamiento térmico en el secado de granos para las condiciones de diseño. Palabras... more
... El resultado del análisis muestra una distribución favorable de las áreas de captación y de pérdidas, por lo que es posible pronosticar un buen funcionamiento térmico en el secado de granos para las condiciones de diseño. Palabras clave: secador rotatorio, secador solar. ...
Nanostructured CdS thin films doped with Cu were synthesized by chemical bath deposition. The structural, morphological, optical and opto-electronic properties of CdS were modified by Cu doping and resulted in the formation of... more
Nanostructured CdS thin films doped with Cu were synthesized by chemical bath deposition. The structural, morphological, optical and opto-electronic properties of CdS were modified by Cu doping and resulted in the formation of nanostructured films. No com- pounds other than CdS were formed in this process. The atomic force microscopy (AFM) studies showed that the particle morphology transformed from spherical to nanostructured or amorphous for un-doped to doped, caused by Cu doping. The optical absorption maxima was displaced for the doped films compared to the un-doped films, so also variation in the band gap energy (Eg) which may be attributed to the variation in the grain size of the films with doping. The intensity of photocurrent response of the doped CdS was reduced compared to the un-doped films, due to the increase in the minority carrier concentration by Cu doping.
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The Nafion perfluorinated membranes are one of the best electrolytes used in the Proton Exchange Membrane Fuel Cell (PEMFC). Some methods have been used to study the electrical properties of Nafion; nevertheless, there are some aspects of... more
The Nafion perfluorinated membranes are one of the best electrolytes used in the Proton Exchange Membrane Fuel Cell (PEMFC). Some methods have been used to study the electrical properties of Nafion; nevertheless, there are some aspects of the conduction process that are not well understood, such as the contribution of the bulk and the interfacial phenomena to the total proton conduction process. In this work the Electrochemical Impedance Spectroscopy (EIS) was employed in a four electrode system to study the protonic charge transport under conditions that simulate the operation of the PEMFC. Two Nafion membranes were evaluated to determine the relation of the activation procedure with the resistance to the protonic charge transference. The results are not only consistent with other measurements but also allow to separate the protonic charge transference process in two stages. Each stage was studied and their electrical parameters were calculated using Electrical Equivalent Circuits.
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Polycrystalline CdTe thin films were prepared by electrodeposition from an aqueous solution containing 1.5 M CdSO 4 and 100–200 μm HTeO 2+. The films were characterized by X-ray diffraction to evaluate the structure. Photoelectrochemical... more
Polycrystalline CdTe thin films were prepared by electrodeposition from an aqueous solution containing 1.5 M CdSO 4 and 100–200 μm HTeO 2+. The films were characterized by X-ray diffraction to evaluate the structure. Photoelectrochemical investigation has been carried ...
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In this work, a sulfated titanium dioxide (STi) catalyst obtained from a commercial TiO2 precursor was synthesized and characterized. The catalyst was sulfated by the simple impregnation method with H2SO4 and subsequently calcined at... more
In this work, a sulfated titanium dioxide (STi) catalyst obtained from a commercial TiO2 precursor was synthesized and characterized. The catalyst was sulfated by the simple impregnation method with H2SO4 and subsequently calcined at different temperatures. The synthesized catalyst was characterized by X-ray Diffraction (XRD), Energy-Dispersive Spectroscopy (EDS), and Scanning Electron Microscopy (SEM). The sulfated catalyst was thermally treated at different temperatures (100, 200, 400, and 600 °C) and evaluated in oleic acid esterification reactions by varying the concentration of the catalyst during the conversion of oleic acid to methyl oleate. The conversion was measured from the variation of the acid index (AI)° and free fatty acids (FFA) during the reaction. The STi catalyst obtained was compared with two homogeneous catalysts, H2SO4 and ferric sulfate [Fe2(SO4)3], evaluating the reaction time in the conversion, from which improvements in the reaction performance of the catalyst synthesized in this work were observed versus the two homogeneous catalysts mentioned earlier. Catalyst reuse cycles were also evaluated as well as their performance in the esterification of waste cooking oil. The best catalyst yields reached values close to 86% in a reaction time of 6 h.
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... 6-8/ Detalles experimentales Se ensayaron diferentes variantes tecnológi-cas para el secado solar de café, éstas fueron: plazoletas tradicionales (Var. 1), plazoletas enne-grecidas (Var. 2), el secador solar multipropósito (Var. 3),... more
... 6-8/ Detalles experimentales Se ensayaron diferentes variantes tecnológi-cas para el secado solar de café, éstas fueron: plazoletas tradicionales (Var. 1), plazoletas enne-grecidas (Var. 2), el secador solar multipropósito (Var. 3), el secador solar de tambor rotatorio (Var. ...
Se diseno un secador solar de tiro forzado, para el secado de productos agricolas. Se realizaron pruebas en condiciones climaticas donde la temperatura ambiente promediaba los 28 grados centigrados y la humedad relativa era del 52 %. El... more
Se diseno un secador solar de tiro forzado, para el secado de productos agricolas. Se realizaron pruebas en condiciones climaticas donde la temperatura ambiente promediaba los 28 grados centigrados y la humedad relativa era del 52 %. El colector solar consta de dos placas una absorbedora (que esta expuesta directamente al sol a traves de los cristales), y otra que constituye el techo de la camara de secado, ambas forman un tunel en el cual se coloca un ventilador para forzar el aire a traves de estas, ademas de una camara de secado. Se hicieron las corridas experimentales para medir la temperatura utilizando termopares Tipo K, dispuestos en la camara de secado, placa absorbedora y en el aire; se midio la humedad relativa en la camara de secado con un equipo Hanna HI-9828, demostrandose finalmente que la eficiencia de este secador es del 45 %, lograndose una humedad relativa del aire en la camara de secado baja, de un 1.5 % como promedio, con una radiacion solar promedio de 700 w/m ...
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In the present work, a methodology that allows optimizing the permanent magnet synchronous generator (PMSG) design by establishing limit values of magnet radius and length that maximize efficiency for the nominal parameters of the wind... more
In the present work, a methodology that allows optimizing the permanent magnet synchronous generator (PMSG) design by establishing limit values of magnet radius and length that maximize efficiency for the nominal parameters of the wind turbine is developed. The methodology consists of two fundamental models. One model calculates the generator parameters from the radius of the magnet base, and the other optimization model determines two optimum generators according to the optimization criteria of maximum efficiency and maximum efficiency with minimum weight starting from the axial length and the radius of the magnet base. For the optimization, the numerical method of the golden section was used. The model was validated from a 10 kW PMSG and the results of two optimum generators are presented according to the optimization criteria. In addition, when the obtained results are compared with the reference electric generator, an increase in efficiency of 1.15% and 0.81% and a reduction in ...
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ABSTRACT The effects of wall heat flux boundary conditions, wall to fluid thermal conductivity ratio and slip flow on heat transfer and entropy generation by considering the conjugate heat transfer problem in microchannels are studied,... more
ABSTRACT The effects of wall heat flux boundary conditions, wall to fluid thermal conductivity ratio and slip flow on heat transfer and entropy generation by considering the conjugate heat transfer problem in microchannels are studied, analytically. The heat transfer equations in the fluid and the finite thickness walls of the microchannel are solved analytically using uniform heat flux boundary conditions at the outer surfaces of the walls with appropriate continuity of temperature and heat flux at the fluid-wall interfaces. Exact analytic solutions for the velocity and temperature fields in the fluid and walls of microchannel are utilized to compute the entropy generation rate. The latter is integrated in the whole region of analysis so that the finite dimensions of the device are considered to get the global entropy generation rate. Finally, this quantity is discussed in detail and investigated considering combined effects of wall and hydrodynamic slip. Findings reveal that it is possible to find optimum values of heat flux across the walls of microchannel where the global entropy generation reaches a minimum. Special attention has been given to the effect of the wall heat flux on optimal values of other parameters. The optimum values of both the slip length and wall to fluid thermal conductivity ratio, where the entropy generation is minimum, decrease with the wall heat flux. Also, optimum values of Peclet number with minimal entropy are found for certain suitable combination of geometrical and physical parameters of the system.
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Page 1. DEVELOPMENT OF WIDE BAND GAP Cd1-xMgx Te/CdS TOP CELLS FOR TANDEM DEVICES Omar S. Martinez 1,2, Roger C. Palomera 1,2, Joel P. Enriquez 3, Claudia M. Alons0 1, Xiangxin Liu5, Nini R. Mathews 1,4, Xavier Mathew 1, * and Alvin D.... more
Page 1. DEVELOPMENT OF WIDE BAND GAP Cd1-xMgx Te/CdS TOP CELLS FOR TANDEM DEVICES Omar S. Martinez 1,2, Roger C. Palomera 1,2, Joel P. Enriquez 3, Claudia M. Alons0 1, Xiangxin Liu5, Nini R. Mathews 1,4, Xavier Mathew 1, * and Alvin D. Compaan 5 ...
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ABSTRACT The effects of slip flow on heat transfer and entropy generation by considering the conjugate heat transfer problem in microchannels are studied, analytically. The heat transfer equations in the fluid and the finite thickness... more
ABSTRACT The effects of slip flow on heat transfer and entropy generation by considering the conjugate heat transfer problem in microchannels are studied, analytically. The heat transfer equations in the fluid and the finite thickness walls of the microchannel are solved analytically using thermal boundary conditions of the third kind at the outer surfaces of the walls and continuity of temperature and heat flux across the fluidewall interfaces. After the analytic solutions for the velocity and temperature fields in the fluid and walls of microchannel are obtained, the entropy generation rate is discussed in detail and investigated considering slip flow and convective effects, simultaneously. The results show that the global entropy generation rate is minimized for certain suitable combination of the geometrical and physical parameters of the system. It is possible to find an optimum slip velocity which leads to a minimum global entropy generation rate. The Nusselt number is also calculated and explored for different conditions. An optimum value of the slip length that maximizes the heat transfer is derived.
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Transparent TiO2 thin films were deposited on soda lime glass by spray pyrolysis method from precursor solutions of peroxo-titanium complex, it was prepared varying the substrate temperature at 230, 280, 330, 380 and 430º C, all films had... more
Transparent TiO2 thin films were deposited on soda lime glass by spray pyrolysis method from precursor solutions of peroxo-titanium complex, it was prepared varying the substrate temperature at 230, 280, 330, 380 and 430º C, all films had thickness of 400 nm, these samples was called Series 1. Series 2 was created by heat-treatment in air at 500º C for 3 hours and cooling for 15 hours. All films were characterized by Profilometric technique, AFM, SEM, EDS, TEM, XRD as well as UV-Vis spectroscopy, the photo catalytic activity was carried out by a photo catalytic reactor using degradation of methylene-blue solution. The main characteristics of Series 1 were its predominant amorphous structure, low porosity in the surface structure and grains agglomerates. Series 2 were characterized by a increase in the polycrystalline structure in both anatase and brookite phases, By the surface roughness and the crystal phases presented in our films, we can say that spraying coating method might be ...
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