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We propose and analyze a high order unfitted hybridizable discontinuous Galerkin method to numerically solve Oseen equations in a domain Ω having a curved boundary. The domain is approximated by a polyhedral computational domain not necessarily fitting Ω . The boundary condition is transferred to the computational domain through line integrals over the approximation of the gradient of the velocity and a suitable decomposition of the pressure in the computational domain is employed to obtain an approximation of the pressure having zero-mean in the domain Ω . Under assumptions related to the distance between the computational boundary and Ω , we provide stability estimates of the solution that will lead us to the well-posedness of the scheme and also to the error estimates. In particular, we prove that the approximations of the pressure, velocity and its gradient are of order h k + 1 , where h is the meshsize and k the polynomial degree of the local discrete spaces. We provide numerical experiments validating the theory and also showing the performance of the method when applied to the steady-state incompressible Navier–Stokes equations.

Resumen: Debido al aumento en el uso de la Tomografía Computada (TC), y en consecuencia, la probabilidad de generar un incremento progresivo de la dosis recibida por los paciente y su relación en el potencial riesgo de los efectos de las radiaciones ionizantes, es importante implementar el uso de niveles de referencia diagnóstico (DRLs) en TC, como herramienta fundamental dentro de un programa de control de calidad que permita la evaluación y optimización de las dosis entregadas a los pacientes según la tarea clínica deseada. Con el objetivo de establecer valores típicos de dosis en TC de cerebro en Clínica Bupa Reñaca, se estudió una muestra de 73 informes dosimétricos generados en un equipo TC Toshiba Aquilion 64, en términos de indicadores de dosis para TC: Índice de dosis en TC por volumen (CTDIvol) y Producto dosis longitud (DLP). Con los datos obtenidos, se estimó el valor del percentil 50 (p50) para cada indicador de dosis, y se determinaron los valores típicos de dosis en cada grupo estudiado según sexo, edad e indicación clínica. Se logró definir y establecer una metodología que permitió la obtención de los valores típicos de dosis para TC de cerebro, optimizando las dosis sin producir una disminución en la calidad de la imagen necesaria para nuestro propósito clínico. Abstract: Due to the increase in the use of Computed Tomography (CT), and consequently, the probability of generating a progressive increase in the dose received by the patient and its relationship in the potential risk of the effects of ionizing radiation, it is important to implement the use of diagnostic reference levels (DRLs) in CT, as a fundamental tool within a quality control program that allows the evaluation and optimization of the doses delivered to patients according to the desired clinical task. In order to establish typical dose values in brain CT at Bupa Reñaca Clinic, a sample of 73 dosimetric reports generated on a Toshiba Aquilion 64 CT unit was studied, in terms of dose indicators for CT: Dose rate on CT by volume (CTDIvol) and Dose Length Product (DLP). With the data obtained, the value of the 50th percentile (p50) for each dose indicator was estimated, and typical dose values were determined in each group studied according to sex, age and clinical indication. It was possible to define and establish a methodology that allowed obtaining typical dose values for brain CT, optimizing the doses without producing a decrease in the image quality necessary for our clinical purpose.

RESUMEN Introduction Hay diferentes estilos de aprendizaje según vía de ingreso de información, los cuales pueden evaluarse con el modelo de programación neurolingüística o VAK (visual, auditivo o kinestésico). En programas académicos altamente competitivos un estilo específico podría jugar un rol en rendimiento académico, originado desde el docente, pudiendo favorecer estudiantes con un estilo mediante su enseñanza. Objetivo Analizar relación entre estilo de aprendizaje según via de ingreso de información de estudiantes de postítulo en otorrinolaringología y rendimiento académico basado en modelo VAK Material y método Estudio corte transversal en residentes de postítulo en otorrinolaringología de universidades chilenas, cuestionario de estilos de aprendizaje para definir estilo preferente, correlación con calificaciones. Estadística no paramétrica con mediana y RIC, análisis con Mann-Whitney, Kruskall-Wallis y Kendall-Tau. Resultados Participaron 45/50 residentes, 31% mujeres, 69% hombres; 29,4 años edad promedio; 4,3 años promedio desde pregrado. 46,6% predominio estilo de aprendizaje visual, 35,5% kinestésico, 8,8% auditivo; género femenino predominio kinestésico, masculino predominio visual (p

RESUMEN En la práctica clínica es habitual el estudio de linfonodos cervicales. La anamnesis y el examen físico orientan la etiología, pero ocasionalmente debemos recurrir a estudios imagenológicos. Esto es muy relevante en contexto de un linfonodo metastásico por un carcinoma escamoso de cabeza y cuello. Para esto podemos utilizar diversas herramientas imagenológicas. El ultrasonido se utiliza para el estudio inicial de una masa cervical en donde clínicamente no queda claro el origen. La tomografía computarizada permite la evaluación de manera global del cuello. Se utiliza ante sospechas o diagnósticos confirmados de carcinoma escamoso de cabeza y cuello. La resonancia magnética tiene utilidad en casos que requieren evaluación de un primario y el cuello, como cánceres de glándulas salivales, base de lengua, lengua oral o piso de boca. El PET-TC es un buen examen a la hora de evaluar un cáncer de cabeza y cuello de primario desconocido y posibles metástasis a distancia, como también cuando se quiere evaluar adenopatías persistentes postratamiento con radioquimioterapia. Tener una evaluación ordenada en el estudio de un linfonodo, por sobre todo con un uso adecuado del recurso imagenológico ayuda a no enlentecer el proceso diagnóstico y dar un diagnóstico y tratamiento más certero. ABSTRACT In clinical practice, the study of cervical lymph nodes is common. The anamnesis and the physical examination often guide the etiology, however sometimes we have to use images studies. This is very relevant when we are assessing a metastatic lymph node due to head and neck squamous cell carcinoma. Ultrasound is usually used for the initial study of a cervical mass where the physician cannot determine its origin. The computed tomography allows a global evaluation of the neck. It is most often used when there is suspicion or confirmed diagnoses of head and neck squamous cell carcinoma. Magnetic resonance imaging is useful in cases that require evaluation of a primary neoplasm and the neck, such in salivary gland cancers, tongue base cancers, oral tongue or mouth floor tumors. PET-CT is a good test to evaluate head and neck cancers of unknown primary site and possible distant metastases, as well as evaluation of persistent adenopathies after treatment with radiochemotherapy. Having an organized evaluation in the study of a lymph node, with an adequate use of the imaging resource, helps not to hinder the diagnostic process and give an accurate diagnosis and treatment.

Ant colony optimization (ACO) algorithms have proved to be suitable for solving dynamic optimization problems (DOPs). The integration of local search operators with ACO has also proved to significantly improve the output of ACO algorithms. However, almost all previous works of ACO in DOPs do not utilize local search operators. In this work, the MAX-MIN Ant System (MMAS), one of the best ACO variations, is integrated with advanced and effective local search operators, i.e., the Lin-Kernighan and the Unstringing and Stringing heuristics, resulting in powerful memetic algorithms. The best solution constructed by ACO is passed to the operator for local search improvements. The proposed memetic algorithms aim to combine the adaptation capabilities of ACO for DOPs and the superior performance of the local search operators. The travelling salesperson problem is used as the base problem to generate both symmetric and asymmetric dynamic test cases. Experimental results show that the MMAS is able to provide good initial solutions to the local search operators especially in the asymmetric dynamic test cases.

RESUMEN El objetivo de la presente investigacion fue determinar en que medida se puede reducir el consumo de energia en el sector residencial de la ciudad de Cuenca, manteniendo optimas condiciones de confort. El estudio se centra en la definicion de indicadores de eficiencia energetica para la vivienda, mediante la determinacion de la demanda de energia y la definicion de los factores de mayor consumo, usando un enfoque cualitativo y cuantitativo. Se realizaron encuestas en 280 viviendas del sector residencial de la ciudad de Cuenca. Paralelamente se monitorizo el consumo de luz y la calidad del ambiente interior de 6 viviendas y se las analizo mediante simulaciones. Los resultados fueron analizados y comparados con los estandares nacionales e internacionales de eficiencia, y utilizados como base para la definicion de las estrategias de reduccion de consumo de energia y la definicion de indicadores minimos de consumo de energia electrica. Palabras clave : Eficiencia energetica, consumo electrico, indicadores de consumo de energia, area residencial, Cuenca. ABSTRACT The objective of the research presented herein was to determine how far in the residential area of the City of Cuenca the consumption of energy can be reduced, maintaining optimal comfort conditions. In addition, the research focused on the definition of energy efficiency indicators for residential homes. The study involved determination of the energy demand and assessment of the major consumption factors using both qualitative and quantitative approaches. Surveys were conducted in 280 households of the residential area of Cuenca. Parallel, light consumption and indoor environmental quality was monitored in 6 houses and reconstructed using simulation models. The results were analysed and compared with national and international standards of efficiency, and used as a basis for defining strategies for reducing energy consumption and the definition of indicators of minimum power consumption. Keywords : Energy efficiency, electrical consumption, energy consumption indicators, residential area, Cuenca.

Organizational agility (OA), as a key dynamic capability, is a firm's ability to enable sensing environmental changes and responding efficiently and effectively to them. This study explores this topic further by analyzing the part that the information systems capabilities (ISC) variable plays as an antecedent of OA, and absorptive capacity (AC) as a mediator construct. Furthermore, this study tests the negative moderating role of hierarchy culture (HC) in the AC–OA link. Using partial least squares (PLS) and the PROCESS macro, this work finds evidence of these relations proposed, and the existence of a conditional mediating situation that HC generates. In addition, the main model with direct effects (ISC and AC as predictors) achieves an appropriate level of predictive validity for the key endogenous construct (OA).

In this article, we present an adaptive color similarity function defined in a modified hue-saturation-intensity color space, which can be used directly as a metric to obtain pixel-wise segmentation of color images among other applications. The color information of every pixel is integrated as a unit by an adaptive similarity function thus avoiding color information scattering. As a direct application we present an efficient interactive, supervised color segmentation method with linear complexity respect to the number of pixels of the input image. The process has three steps: (1) Manual selection of few pixels in a sample of the color to be segmented. (2) Automatic generation of the so called color similarity image (CSI), which is a gray level image with all the gray level tonalities associated with the selected color. (3) Automatic threshold of the CSI to obtain the final segmentation. The proposed technique is direct, simple and computationally inexpensive. The evaluation of the efficiency of the color segmentation method is presented showing good performance in all cases of study. A comparative study is made between the behavior of the proposed method and two comparable segmentation techniques in color images using (1) the Euclidean metric of the a* and b* color channels rejecting L* and (2) a probabilistic approach on a* and b* in the CIE L*a*b* color space. Our testing system can be used either to explore the behavior of a similarity function (or metric) in different color spaces or to explore different metrics (or similarity functions) in the same color space. It was obtained from the results that the color parameters a* and b* are not independent of the luminance parameter L* as one might initially assume in the CIE L*a*b* color space. We show that our solution improves the quality of the proposed color segmentation technique and its quick result is significant with respect to other solutions found in the literature. The method also gives a good performance in low chromaticity, gray level and low contrast images.© 2016 Wiley Periodicals, Inc. Col Res Appl, 00, 000–000, 2016

The task consists in estimating the personality traits of users from their handwritten texts. To classify them, we use the scanned image of the subject hand-written essay divided in patches and we propose in this work an architecture based on a Convolutional Neural Network (CNN) as classifier. The original dataset consists of 418 images in color, from which we obtained 216 patches of each image in grayscale and then we binarized them resulting in approximately 90,000 images. The CNN consists of five convolutional layers to extract features of the patches and three fully connected layers to perform the classification.

Resumen Introducción: Desde la década de los 90, los implantes cocleares han progresado desde aplicaciones experimentales a un uso clínico estandarizado en niños con pérdida auditiva severa y profunda. Las investigaciones han producido cambios en la tecnología de los implantes y ha dado lugar a la expansión de los candidatos a implante para incluir a los niños menores de 2 años de edad. El objetivo principal de la implantación coclear pediátrica es facilitar el desarrollo del lenguaje hablado. A pesar de los avances en la tecnología de implantes y los cambios en el manejo de la pérdida auditiva, los resultados de lenguaje en niños son todavía muy variables, participando de este proceso tanto el tratamiento oportuno, la red familiar y nivel socioeconómico entre algunos de ellos. Objetivo: Describir resultados de niños menores 6 años sometidos a cirugía de implante coclear en un centro terciario de salud. Material y método: Estudio longitudinal de cohorte retrospectivo, análisis a 99 pacientes implantados en centro terciario de salud desde inicio programa en 1994 a 2015. Resultados: 99 pacientes, 57% hombres 43% mujeres, edad promedio implantación 16,3 meses. 54,8% casos origen congénito no especificado o prematurez. En 74,4% se objetivó presencia de lenguaje auditivo verbal. El nivel socioeconómico (NSE) mostró asociación con no desarrollo de lenguaje (p =0,009) evidenciando que pacientes de bajo NSE 20% no desarrolla lenguaje. La variable discapacidad asociada (p

Background: Pulmonary nodules are common, and surgery is the only alternative that allows a diagnostic and therapeutic management in a single procedure. Aim: To report the epidemiological, radiological, surgical and pathological features of excised pulmonary nodules. Material and Methods: Review of medical records of patients in whom a pulmonary nodule was excised between 2014 and 2018. Those with incomplete data or without a pathological study were excluded from analysis. Results: We retrieved 108 records and 8 had to be excluded, therefore 100 patients aged 34 to 82 years (57% females) were analyzed. Sixty percent had a history of smoking. Mean nodule size was 16 mm and the solid type was the most common (65%). Forty five percent of nodules had irregular margins and 55% were in the superior lobes. All patients operated by video-assisted thoracoscopic surgery and 40% underwent a lobectomy. Malignant lesions were observed in 87% of biopsies and a pulmonary adenocarcinoma was found in pathology in 40%. Conclusions: A multidisciplinary approach of pulmonary nodules, using adapted international guidelines, accomplishes an appropriate management, decreasing unnecessary surgical interventions.

Direct Travel System (SRD) is a technological system that allows you to count of passenger that use taxi sharing service for the purpose of reporting the exact number of passengers who used the mobile, as well as inform the potential passenger of what the route is and what is the capacity availability. The functionality of the system start for passenger detection through weight sensors installed inside of the vehicle publishing both inside and outside the state of gauging through different high resolution interfaces, passenger rise and fall events are recorded in a memory, wich are downloaded when mobile arrive to own base station. The data available is used to obtain information for control the route of mobile, as well as to exercise better regulation, inspection and planning by authorities. At this moment the system is in full development, generating three copies to be installed in respective cars.

RESUMEN Introducción: La hipoacusia sensorioneural es la tercera causa de discapacidad en Chile, con incidencia en recién nacidos de 1 a 3 casos cada 1.000 recién nacidos vivos, y prevalencia en adultos de hasta 70%, siendo muchos casos susceptibles de ser tratados mediante implante coclear. Objetivo: Describir resultados de los pacientes sometidos a cirugía de implante coclear en Clínica Las Condes (CLC). Material y método: Estudio longitudinal de cohorte retrospectiva, se analizaron a 237 pacientes implantados en Clínica Las Condes desde 1994 al año 2015. Resultados: Se analizan 237 pacientes, 106 mujeres (44,7%) y 131 hombres (55,3%). El 65,5% de los pacientes se implantaron entre los 2-6 años de vida. Las etiologías más frecuentes fueron hipoacusia congénita no sindrómica (45,9%), genética tardía (11,8%) y posmeningitis (11,4%). Se encontró asociación significativa entre promedio tonal de la palabra (PTP) y presencia de malformación coclear (p =0,008). Sólo 9,9% de los pacientes presentaron otra discapacidad asociada a la hipoacusia. La tasa de reimplante fue 16,3% y sólo la variable malformación coclear se asoció a ella (p =0,016). Conclusión: El implante coclear es una herramienta beneficiosa en pacientes hipoacúsicos que no se benefician de otros dispositivos auditivos ofreciendo la posibilidad de reinsertarlos social y laboralmente con bajo riesgo quirúrgico y alta tasa de éxito. ABSTRACT Introduction: Sensorineural hearing loss is the third leading cause of disability in Chile, with incidence in infants 1 to 3 cases per 1,000 newborn and prevalence in adult up to 70%, with many cases that can be treated with cochlear implant. Aim: to describe outcomes of our series of patients undergoing cochlear implant surgery at Clinica Las Condes (CLC). Material and method: Retrospective longitudinal cohort study, 237 patients implanted in our center since 1994 to 2015 were analyzed. Results: 237 patients, 106 women (44.7%) and 131 men (55.3%) received a cochlear implant during this period. 65.5% of patients were implanted between 2-6 years of age. The most common etiologies were; non-syndromic congenital deafness (45.9%), late genetic onset (11.8%) and meningitis (11.4%). A significant association between the average pure tone average and presence of cochlear malformation (p =0.008) was demonstrated. Only 9.9% of patients had other disabilities associated with hearing loss. Re-implantation rate was 16.3% and only the variable cochlear malformation was associated to it (p =0.016) Conclusions: The cochlear implant provides clear benefits to patients with hearing impairment who do not benefit from other hearing devices offering the possibility of social and labor reintegrating, with low surgical risk and high success rate.

Actualmente, uno de los problemas que prevalecen en la sociedad son las enfermedades bucales, las cuales, por falta de información no son tratadas a tiempo o en ocasiones jamás, lo que lleva a grandes consecuencias en la salud; uno de los problemas más comunes son las maloclusiones dentales, de éstas a muchas personas no les interesa someterse a un tratamiento adecuado.De acuerdo a estudios epidemiológicos, se ha mostrado que la maloclusión se presenta con tasas de prevalencia considerablemente altas, ya que más de 60% de la población la desarrolla. Las investigaciones sobre maloclusiones en niños de 4 a 5 años reportan prevalencias de 70-80%, que evolucionan hasta encontrar tasas de prevalencia de 96.4% en adolescentes. [2]En el presente proyecto, se desarrolla un estudio de Maloclusiones dentales llevándolo, a predecir el éxito o fracaso en el tratamiento de ortodoncia, esto, a través de diversas técnicas de Minería de Datos, haciendo uso de algoritmos mismos de esta materia para crear un modelo predictivo. De la mano de Weka, una herramienta de Minería de Datos se comienza a modelar los datos para que arrojen reglas destinadas a crear un árbol de decisión.Como resultado se obtuvieron diversas reglas con relación a las enfermedades de Maloclusiones dentales, tales, con las que se desarrolló una interfaz gráfica para mayor interacción entre el programa y el paciente.

In this paper an evaluation of the influence of luminance L* at the L*a*b* color space during color segmentation is presented. A comparative study is made between the behavior of segmentation in color images using only the Euclidean metric of a* and b* and an adaptive color similarity function defined as a product of Gaussian functions in a modified HSI color space. For the evaluation synthetic images were particularly designed to accurately assess the performance of the color segmentation. The testing system can be used either to explore the behavior of a similarity function (or metric) in different color spaces or to explore different metrics (or similarity functions) in the same color space. From the results is obtained that the color parameters a* and b* are not independent of the luminance parameter L* as one might initially assume.

In this paper a study of the influence of luminance L* at the CIE L* a* b* color space during color segmentation in highly saturated color images is presented. A comparative study is made between the behavior of segmentation in color images using (1) the Euclidean metric of the RGB channels (2) the Euclidean metric of a* and b* in CIE L*a*b* color space and (3) an adaptive color similarity function defined as a product of Gaussian functions in a modified HSI color space. For the evaluation, synthetic images were particularly designed to accurately assess the performance of the color segmentation. The testing system can be used either to explore the behavior of a similarity function (or metric) in different color spaces or to explore different metrics (or similarity functions) in the same color space. From the results it was obtained that the color parameters a* and b* are not independent of the luminance parameter L* as one might initially assume. In the majority of cases the CIE L*a*b color space was more influenced by the faded shadow than the RGB color space. The segmentation using the Euclidean metric in L*a*b* color space suffered errors in all cases. It manifested in different degrees and at different levels of faded shadow (less than 10% to 80%).

In this paper a study of the influence of luminance L* at the L* a* b* color space during color segmentation is presented. The behavior of different color image segmentation algorithms is studied, in particular, the techniques based on only the Euclidean metric of a* and b* and an adaptive color similarity function defined as a product of Gaussian functions in a modified HSI color space. For the evaluation purposes, synthetic images that accurately assess the performance of the color segmentation were particularly designed. The testing system can be used either to explore the behavior of a similarity function (or metric) in different color spaces or to explore different metrics (or similarity functions) in the same color space. From the obtained results it follows that the color parameters a* and b* are not independent on the luminance parameter L* as one may initially assume.