1,736 research outputs found
Detección y localización automática de la superficie facial en imágenes 3d de una profundidad
La detección del rostro es uno de los primeros pasos en las aplicaciones de procesamiento facial, cuyo propósito es identificar y localizar todos los rostros que se encuentran en una imagen, independientemente de su posición, escala y orientaciones. En esta tesis se reporta la investigación realizada en la Maestría en Ciencias de la Ingeniería de la Universidad Autónoma del Estado de México para detectar y localizar automáticamente la superficie facial utilizando imágenes 3D de una profundidad con variaciones en número y posición de las personas en la escena. Para esto se revisó la literatura relacionada y se discute la problemática actual en la detección de la superficie facial en imágenes 3D. Se propone y evalúa experimentalmente una técnica para la detección de la superficie facial automáticamente con variaciones en el número de usuarios y su posición con respecto a la cámara. Esta técnica consta de cuatro etapas: a) Eliminación de partes planas en la imagen 3D utilizando el algoritmo MSAC, b) Análisis de curvatura para detectar puntos convexos, c) Selección automática de la punta de la nariz utilizando SpinImages y d) Clasificación rostro o no rostro. En esta investigación se utilizó el sensor Kinect One™, para colectar una base de datos de 1020 imágenes 2D/3D variando el número y posición en la escena de treinta y dos sujetos. Las imágenes 3D colectadas fueron utilizadas para la evaluación de nuestro proceso de detección de la superficie facial. Este proceso ha sido capaz de detectar con éxito el 91% de los rostros en las imágenes colectadas que contienen más de un sujeto en la escena, y el 100% y 98% de los rostros contenidos en las bases de datos Face Recognition Grand Challenge y CurtinFaces, respectivamente. En ese sentido, se obtuvieron resultados que son alentadores para abordar el problema general en la detección de la superficie facial en condiciones no controladas, con más de una persona en la escena y variación en su posición con el objetivo de crear sistemas de procesamiento facial automáticos.CONACYT (CVU: 634473
Application of a sensitivity analysis technique to high-order digital flight control systems
A sensitivity analysis technique for multiloop flight control systems is studied. This technique uses the scaled singular values of the return difference matrix as a measure of the relative stability of a control system. It then uses the gradients of these singular values with respect to system and controller parameters to judge sensitivity. The sensitivity analysis technique is first reviewed; then it is extended to include digital systems, through the derivation of singular-value gradient equations. Gradients with respect to parameters which do not appear explicitly as control-system matrix elements are also derived, so that high-order systems can be studied. A complete review of the integrated technique is given by way of a simple example: the inverted pendulum problem. The technique is then demonstrated on the X-29 control laws. Results show linear models of real systems can be analyzed by this sensitivity technique, if it is applied with care. A computer program called SVA was written to accomplish the singular-value sensitivity analysis techniques. Thus computational methods and considerations form an integral part of many of the discussions. A user's guide to the program is included. The SVA is a fully public domain program, running on the NASA/Dryden Elxsi computer
Britain's pivot to Asia: the perils & possibilities of post-Brexit politics
As the United Kingdom prepares to leave the European Union, will the Brexiteers’ vision of a “Global Britain” finally emerge? Will a pivot to Asia unlock the possibilities they claim? In this Strategic Update, Stephen Paduano explores the future of British engagement in the Indo-Pacific, the opportunities that exist, and the dangers that lie ahead
Black Holes and Neutron Stars in Galactic Globular Clusters
In this thesis I observed black holes and neutron stars in Galactic globular clusters with radio and X-ray telescopes to explore the unique properties of these systems. I investigated the extreme and unusual accretion scenarios that are found in these systems. Finally, I created the most sensitive radio image made using an Australian radio telescope to detect the very faintly accreting black holes in globular clusters in preparation for science with the Square Kilometre Array
Effects of Glucagon-Like Peptide 1 Receptor Agonist and Sodium-glucose Cotransporter-2 Inhibitors on the N-terminal prohormone of brain natriuretic peptide concentrations: a meta-analysis approach.
openThe purpose of this work is to demonstrate, through a meta-analysis of the main scientific works on the subject, the efficacy of two categories of recently introduced drugs in the therapy of diabetes - glucagon-like peptide 1 receptor agonists (GLP-1) and sodium-glucose cotransporters 2 inhibitors (SLGT-2) - with particular attention to patients with heart failure.
With worsening epidemiological trends for both the incidence and prevalence of type 2 diabetes mellitus (T2DM) and heart failure (HF) worldwide, it is critical to implement optimal prevention and treatment strategies for patients with these comorbidities, either alone or concomitantly. Several guidelines and consensus statements have recommended GLP-1 and SLGT-2 as add-ons to lifestyle interventions with or without metformin in those at high atherosclerotic cardiovascular disease risk.
In addition to the international health emergency represented by diabetes with the consequent increase in cardiovascular diseases, the scope of this thesis is to describe the mechanisms of action of the aforementioned molecules and methods used in the meta-analysis
Book review: the price of peace: money, democracy, and the life of John Maynard Keynes by Zachary D. Carter
In The Price of Peace: Money, Democracy, and the Life of John Maynard Keynes, Zachary D. Carter offers a new intellectual biography tracing the life and legacy of the influential economist, which argues that in the years since Keynes’s death, Keynesian economics has been stripped of Keynesian thought. Weaving together a dazzling array of Keynes’s private letters, journalistic works and academic research, this accessible book may help to hasten Keynes’s revival, writes Stephen Paduano
Development of a sensitivity analysis technique for multiloop flight control systems
This report presents the development and application of a sensitivity analysis technique for multiloop flight control systems. This analysis yields very useful information on the sensitivity of the relative-stability criteria of the control system, with variations or uncertainties in the system and controller elements. The sensitivity analysis technique developed is based on the computation of the singular values and singular-value gradients of a feedback-control system. The method is applicable to single-input/single-output as well as multiloop continuous-control systems. Application to sampled-data systems is also explored. The sensitivity analysis technique was applied to a continuous yaw/roll damper stability augmentation system of a typical business jet, and the results show that the analysis is very useful in determining the system elements which have the largest effect on the relative stability of the closed-loop system. As a secondary product of the research reported here, the relative stability criteria based on the concept of singular values were explored
A COMPARISON OF UNIDIMENSIONAL AND MULTIDIMENSIONAL LOCUS OF CONTROL SCALES FOR THE MEASUREMENT OF THE EFFECTS OF SELF-REGULATION TRAINING
Comprehensive training in self regulation (SR) (including biofeedback training, relaxation techniques, and cognitive therapy principles) has been proposed as a means of affecting change in individual locus of control (LOC) orientation. The current study directly compared a uni-dimensional LOC scale (Ratter, 1966) with a multidimensional LOC scale (Levenson, 1973) in the ability to detect changes in the LOC orientation. Other effects of SR training were measured by the State-Trait Anxiety Scale (STAY) and the Irrational Beliefs Test (IBT). Nineteen participants in a biofeedback/stress reduction class completed a course in SR training. The pre-test/post-test results were compared with those of a matched control group. Results indicated SR training did not affect either state anxiety or LOC orientation as measured by the instruments. Consequently, the comparison of the two LOC scales revealed no differences and the null hypothesis could not be rejected. However, the scores on the IBT indicated the experimental group significantly decreased in their scores on four irrational beliefs (p‹.05) while the control group decreased in one irrational belief (p‹.05). It was concluded that SR training decreased some aspects of irrationality in participants
Ultrasound in Olive Oil Extraction
Each olive oil extraction system should combine the best product quality and the highest efficiency. At the same time, the innovative technologies can develop only if they provide sustainable processes. To reach these goals, academic and industrial researchers need to understand the key elements that allow to modulate the events that occur during oil extraction. In the past years, many emerging technologies, that is techniques perceived as capable of changing the present situation, have been developed. Among these, ultrasounds applications seem to be the most promising for their mechanical and slightly thermal effects, without affecting sustainability. In order to explain the maturity of this emerging technology, the main effects of the ultrasounds application in the olive oil extraction process are discussed, the developed plants are presented, and the patents are reported
Potential use of human periapical cyst-mesenchymal stem cells (hPCy-MSCs) as a novel stem cell source for regenerative medicine applications
Mesenchymal stem cells (MSCs) are attracting growing interest by the scientific community due to their huge regenerative potential. Thus, the plasticity of MSCs strongly suggests the utilization of these cells for regenerative medicine applications. The main issue about the clinical use of MSCs is related to the complex way to obtain them from healthy tissues; this topic has encouraged scientists to search for novel and more advantageous sources of these cells in easily accessible tissues. The oral cavity hosts several cell populations expressing mesenchymal stem cell like-features, furthermore, the access to oral and dental tissues is simple and isolation of cells is very efficient. Thus, oral-derived stem cells are highly attractive for clinical purposes. In this context, human periapical cyst mesenchymal stem cells (hPCy-MSCs) exhibit characteristics similar to other dental-derived MSCs, including their extensive proliferative potential, cell surface marker profile and the ability to differentiate into various cell types such as osteoblasts, adipocytes and neurons. Importantly, hPCy-MSCs are easily collected from the surgically removed periapical cysts; this reusing of biological waste guarantees a smart source of stem cells without any impact on the surrounding healthy tissues. In this review, we report the most interesting research topics related to hPCy-MSCs with a newsworthy discussion about the future insights. This newly discovered cell population exhibits interesting and valuable potentialities that could be of high impact in the future regenerative medicine applications
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