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Tracking control of the boost converter

DOMINGO DE JESUS CORTES RODRIGUEZ (2004)

"The tracking control problem of amplifying converters encompasses an important practical concern and a challenging theoretical problem. These converters are nonlinear, nonminimum phase systems with saturated control and a highly variable parameter (the load). Such characteristics make amplifying converters devices difficult to control, even for the regulation case. Several aspects of the tracking control problem of the boost converter are addressed. A characterisation of the signal the converter is able to follow is given. The relationship between the parameter values and the tracking error is established, and it is shown that adequate parameters for the DC-to-DC converter are not always suitable for DC-to-AC conversion."

Article

Nonlinear control systems, Voltage control, Power amplifiers, Closed loop systems, DC-DC power convertors CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA FÍSICA ELECTRÓNICA

Robust H∞ control of glycemia in Type 2 Diabetes Mellitus via continous insulin plus Metformin

NELIDA ELIZABETH LOPEZ PALAU CLAUDIA PATRICIA FLORES GUTIERREZ Alejandro Ricardo Femat Flores (2018)

"Several studies have shown that an adequate therapy for glycemic control in patients with type 2 diabetes mellitus (T2DM) can delay or prevent complications derived from this condition. To achieve the control objectives an adequate therapy should be performed by using insulin alone or in combination with an oral hypoglycemic agent. However, the key point of glycemic control is to determine the amount of insulin to be delivered. In order to achieve the above different strategies have been proposed, one of them is the design of feedback control algorithms. In this article a robust feedback control algorithm of glycemia in T2DM was designed. The algorithm determines the continuous insulin infusion to be delivered to maintain normoglycemia considering a combined therapy with a dose of metformin. The problem approach was to find a controller that minimized in the sense of the H? norm: i) the difference between the glycemia of a T2DM patient and a healthy subject (tracking problem) and ii) the effect of disturbances due to glucose intake and noise from a glucose sensor."

Article

Robust control Dynamic modelling Closed-loop Control Biomedical systems Pharmacokinetic-Pharmacodynamic modelling CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA MATEMÁTICAS MATEMÁTICAS

Complete stability region of PD controllers for TCP/AQM networks

ADRIAN KARIN PUERTO PIÑA DANIEL ALEJANDRO MELCHOR AGUILAR (2016)

"This paper addresses the stabilization problem of delay models of Transmission Control Protocol/Active Queue Management (TCP/AQM) by using a Proportional- Derivative (PD) controller as AQM strategy. The complete set of PD controllers that exponentially stabilizes the linearization is determined in counterpart with the existing works in the literature which only give an estimate of it. Additionally, a simple procedure for determining a non-fragile PD controller that admits controller coefficient perturbations is provided."

Lecture

PD control Delay systems Stability analysis Mathematical model Delays Closed loop systems Aerospace electronics CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA MATEMÁTICAS

Further results on the global continuous control for finite-time and exponential stabilization of constrained-input mechanical systems: desired conservative-force compensation and experiments

Griselda Ivone Zamora Gómez Arturo Zavala Río DANIELA JUANITA LOPEZ ARAUJO Victor Santibanez (2019)

"Saturating-Proportional-Derivative (SPD) type global continuous control for the finite-time or (local) exponential stabilization of mechanical systems with bounded inputs is achieved involving desired conservative-force compensation. Far from what one could expect, the proposed controller is not a simple extension of the on-line compensation case but it rather proves to entail a closed-loop analysis with considerably higher degree of complexity. This gives rise to more involved requirements to guarantee its successful performance and implementability. Interesting enough, the proposal even shows that actuators with higher power-supply capabilities than in the on-line compensation case are required. Other important analytical limitations are further overcome through the developed algorithm. Experimental tests on a 2-degree-of-freedom robotic arm corroborate the efficiency of the proposed scheme."

Article

Actuators Asymptotic stability Closed loop systems Compensation Continuous systems Control system synthesis PD control CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA MATEMÁTICAS MATEMÁTICAS

Control visual de manipuladores en ambiente con objeto móvil

Visual servoing of robot manipulators tracking a moving target

Ana María Hernández Campos (2000)

En esta tesis se propone un control servo visual para un robot manipulador planar de 2 g.d.l., en configuración de cámara fija y siguiendo un objeto que recorre una trayectoria de forma conocida pero con parámetros desconocidos; por ello se dirá que sigue una trayectoria semi-estructurada. Una cámara de video sensa el objeto móvil y el extremo operativo del robot; una etapa de procesamiento de imágenes obtiene los centroides del extremo operativo del manipulador y del objeto móvil. La diferencia de posición entre ambos centroides se le denomina error en coordenadas de pantalla o de imagen. El problema de control consiste en lograr que el error en coordenadas de imagen presente convergencia a cero. La solución propuesta a este problema de control se basa en un sistema de doble lazo de control. El lazo interno es un controlador de velocidad articular y el lazo externo un controlador basado en coordenadas de imagen. Debido a que se han supuesto desconocidos los valores de los parámetros que describen la trayectoria del objeto móvil, la solución adoptada en esta tesis se inspira en técnicas de control adaptable. En este documento se presenta el controlador, un análisis de estabilidad de sistema propuesto y se comprueba la convergencia a cero del error en coordenadas de pantalla. También, se muestran resultados de la simulaciones del sistema; se supone que el objeto móvil recorre una trayectoria circular en la pantalla de un monitor, desconociéndose el valor de radio y la ubicación del centro del círculo.

In the present dissertation a law control is proposed for visual servoing of 2 DOF planar robot manipulator whose end-effector must track a moving target under fixed camera configuration. The moving target covers a trayectory with a known form but its description parameters are unknown; because of this, the path is denominated as a semi-structured path. A video camera senses both, end-effector ang the moving target; an image processing system calculates their centroids. The difference between the end-effector and moving target centroids is referenced as image feature error. The control problem objective is to ensure that the image error converges to zero. To achieve this goal, a two-loop control system is proposed. The inner loop consists of a joint velocity controller and the outer loop is comprised of an image-based controller. Due to the unknown path parameters, the solution proposed in this thesis is inspired in the adaptive control techniques. In this document we addressed the controller, a stability analysis for the proposed system is performed, and image feature error convergence to zero is demonstrated. Also, simulations results are presented, under the assumption that the moving target does a circular path on the screen but its radio and center location are unknown.

Master thesis

Robot,Control servo visual,Doble lazo de control,Control adaptable,Controlador de velocidad articular,Cámara fija,Visual servoing,Two-loop controller, Adaptative control,Joint velocity controller,Fixed camera INGENIERÍA Y TECNOLOGÍA CIENCIAS TECNOLÓGICAS TECNOLOGÍA DE LAS TELECOMUNICACIONES

Propagación de pulsos de luz en un lazo cerrado resonante de fibra óptica dopada con erbio

Slow and fast light propagation in the closed-loop cavity controlled by saturation of erbium doped fiber

Anna Shlyagina (2013)

Se presentan los resultados del estudio sobre la propagación de luz modulada en intensidad en una configuración de lazo cerrado de fibra óptica con un segmento de fibra dopada con erbio incorporado a éste. Existen tres regímenes de operación de la cavidad resonante de este tipo: undercoupling (con la transmitancia del lazo t menor que la transmitancia del acoplador κ), acoplamiento ideal (t=κ) y el régimen overcoupling (t>κ). Es bien conocido que controlando las pérdidas dentro del lazo (t) y modificando el acoplamiento con la cavidad es posible cambiar el retraso temporal de la señal trasmitida y pasar de un retraso a un adelanto de pulsos de luz. Primeramente se estudió una cavidad formada únicamente de fibra óptica convencional monomodo y, en particular, la influencia de la polarización de la luz incidente, la longitud de lazo cerrado y la atenuación dentro del anillo. Así mismo se observó la propagación de la señal con longitud de onda resonante bajo los regímenes overcoupling y undercupling en donde las pérdidas dentro de lazo cerrado fueron controladas mecánicamente mediante el doblez de la fibra. La parte original de este trabajo es que la transmitancia del lazo cerrado fue controlada ópticamente por la intensidad de la potencia de luz incidente la cual cambia la saturación de fibra dopada con erbio. Se estudió la saturación de fibra dopada y la propagación de la luz modulada a través de esta configuración resonante en donde variando la potencia incidente al lazo se pudo observar los tres regímenes de operación principales. Se obtuvo como resultado, un cambio controlado de adelanto de la señal óptica de salida en el régimen overcoupling y un retraso en el undercoupling. Los datos experimentales fueron validados con el análisis teórico, obteniendo una buena concordancia entre ellos.

This thesis presents original results on study of propagation of modulated intensity signals in fiber optic system containing a close-loop resonator with an incorporated section of the Er-doped fiber. There are three operating regimes of the resonant cavity of this type: undercoupling (transmittance of the loop,t, is less than coupler transmittance, κ), ideal coupling (tκ=) and the overcoupling regime (tκ>). It is well known that controlling the losses within the loop (t) and varying the coupling of the cavity is possible to modify the time delay of the transmitted signal and change from a delay to an advancement of the light pulse. Firstly, a resonator formed by only a conventional single-mode optical fiber was studied. The influence of the polarization of light, length of the loop resonator, attenuation within the ring and others effects were analyzed. Also the propagation of a signal inside the loop under these three regimes was investigated. The losses within the system were created mechanically by bending the optical fiber. The original part of this work is the fact that the closed loop transmittance was optically controlled by the intensity of incident light power which changes the saturation of erbium-doped fiber. The light signal propagation through this configuration was studied. Varying the incident power allowed us to observe all three regimes of the cavity operation. It was demonstrated an advance of the output signal in the overcoupling regime and delay of the signal in undercoupling regime The experimental data were compared with theoretical data and a good agreement between them was obtained.

Master thesis

Fast-slow light,Light pulses,Closed loop optical resonator,Regime overcoupling,Propagación de luz modulada,Fibra dopada con erbio,Régimen undercoupling,Régimen overcoupling,Resonador óptico de lazo cerrado,Pulsos de luz,Propagation of modulated light,Erbium doped fiber,Regime undercoupling CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA FÍSICA ÓPTICA ÓPTICA

Chromatin loop formation induced by a subtelomeric protosilencer represses EPA genes in Candida glabrata

EUNICE LOPEZ FUENTES GRECIA HERNANDEZ HERNANDEZ Leonardo Castanedo Ibarra Ma. Guadalupe Gutiérrez Escobedo KATARZYNA OKTABA SOSIN Alejandro de las Peñas Nava Irene Beatriz Castaño Navarro (2018)

"Adherence, an important virulence factor, is mediated by the EPA (Epithelial Adhesin) genes in the opportunistic pathogen Candida glabrata. Expression of adhesin-encoding genes requires tight regulation to respond to harsh environmental conditions within the host. The majority of EPA genes are localized in subtelomeric regions regulated by subtelomeric silencing, which depends mainly on Rap1 and the Sir proteins. In vitro adhesion to epithelial cells is primarily mediated by Epa1. EPA1 forms a cluster with EPA2 and EPA3 in the right telomere of chromosome E (E-R). This telomere contains a cis-acting regulatory element, the protosilencer Sil2126 between EPA3 and the telomere. Interestingly, Sil2126 is only active in the context of its native telomere. Replacement of the intergenic regions between EPA genes in E-R revealed that cis-acting elements between EPA2 and EPA3 are required for Sil2126 activity when placed 32 kb away from the telomere (Sil@-32kb). Sil2126 contains several putative binding sites for Rap1 and Abf1, and its activity depends on these proteins. Indeed, Sil2126 binds Rap1 and Abf1 at its native position and also when inserted at ?32 kb, a silencing-free environment in the parental strain. In addition, we found that Sil@-32kb and Sil2126 at its native position can physically interact with the intergenic regions between EPA1-EPA2 and EPA2-EPA3 respectively, by chromosome conformation capture assays. We speculate that Rap1 and Abf1 bound to Sil2126 can recruit the Silent Information Regulator complex, and together mediate silencing in this region, probably through the formation of a chromatin loop."

Article

Candida glabrata Cis-elements Transcriptional regulation Protosilencer EPA genes Rap1 Chromatin loop BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA GENÉTICA GENÉTICA

Estudio de la diversidad genética y manejo tradicional del guajolote autóctono (Meleagris gallopavo) del centro de México

ALEJANDRO ESTRADA MORA (2014)

Tesis (Doctorado en Ciencias, especialista en Ganadería).- Colegio de Postgraduados, 2014.

El guajolote autóctono de México es un recurso zoogenético de gran importancia al ser este país su centro de origen y domesticación. Para conocer más acerca de su situación se planteó investigar en localidades indígenas del centro de México sus características genéticas y de manejo. En el ámbito genético se estudió el fenotipo, caracterizando variables morfológicas, como son, mediciones de tarso, cuerda alar, pico, cola y masa corporal, creando un modelo respecto a los factores plumaje, pigmento de tarso y localidad para un análisis de regresión mediante GLM y un análisis estadístico multivariado de componentes principales; para el genotipo se valoraron dos genes mitocondriales D-Loop y COI dentro y entre poblaciones de guajolote autóctono y fueron comparadas con las de individuos híbridos comerciales y silvestres obteniendo secuencias de los dos genes de 42 individuos, las cuáles se ensamblaron y alinearon con lo que se detectaron los niveles de polimorfismo de cada uno de los genes. Respecto al manejo se aplicó una encuesta teniendo como instrumento un cuestionario (n=65) obteniendo información en la que se llevó a cabo un análisis de correspondencia, tablas de contingencia IxJ, prueba de Chi cuadrada y pruebas no paramétricas como medidas de asociación. Los resultados muestran que la longitud de tarso y el peso explican la variabilidad tanto en las hembras como en los machos de acuerdo al análisis de CP, mientras que, las diferencias como resultado del análisis de GLM no son suficientes para discriminar grupos o variedades; sin embargo, las características peculiares en la diversidad del plumaje que comparte con el guajolote mesoamericano y que lo distingue de otras poblaciones de guajolote doméstico, podría hacerlo susceptible para proponerlo como variedad, raza o ecotipo; el citocromo oxidasa I (COI) no es informativo en tanto que el gen D-Loop, presentó polimorfismo dentro y entre las poblaciones; la reconstrucción de la filogenia señala que los guajolotes autóctonos de México conservan información genética, de la cual derivan las subpoblaciones de otras regiones; el manejo en alimentación, confinamiento y uso manifiesta coincidencias; no existe asociación en el tipo de enfermedades que les afectan y en la supervivencia de los guajolotes. _______________ STUDY OF GENETIC DIVERSITY AND AUTOCHTHONOUS TURKEY (Meleagris gallopavo) TRADITIONAL HANDLING IN CENTRAL MEXICO. ABSTRACT: The Mexican autochthonous turkey is a very important animal genetic resource since Mexico is its centre of origin and domestication. In order to know more about its situation, a research on its genetic characteristics and handling was therefore carried out in indigenous communities of Central Mexico. In the field of Genetics, the phenotype was studied by characterising morphological variables, such as tarsus, wing chord, beak, tail and body mass measurements in order to create a model regarding plumage, tarsus pigment and location so a regression analysis by means of GLM and a multivariate statistical analysis of main components could be both performed. For genotype two mitochondrial genes D-Loop and COI within and among populations of indigenous turkeys were evaluated and were compared with those of commercial hybrid and wild individuals obtaining sequences of the two genes of 42 individuals, which were assembled and aligned with what polymorphism levels of each of the genes were detected. Regarding handling of turkeys, a survey was conducted by means of a questionnaire (n=65) to obtain information that was studied by a correspondence analysis, an IxJ contingency table, a chi-squared test and nonparametric tests as measures of association. The results show that the weight and tarsus length explain the variability in both females and males according to the analysis of CP while differences result GLM analysis are insufficient to discriminate groups or varieties, however peculiar plumage in diversity shared with the Mesoamerican turkey and distinguishes it from other domestic turkey populations could make it susceptible to propose it as variety, race or ecotype; cytochrome oxidase I (COI) is not informative while the D-Loop gene, presented polymorphism within and among populations; reconstructing the phylogeny indicates that the native turkeys in Mexico retain genetic information, which subpopulations derived from other regions; feeding, confinement and usage management show some coincidences. Finally, there is no relation regarding the type of diseases or the survival that affect them.

Doctoral thesis

Guajolote autóctono Indígenas Manejo Morfología D-Loop COI Autochthonous turkey Handling Morphology Ganadería Doctorado CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA

Análisis de la interacción entre las proteínas ABF1 y RAP1 de Candida glabrata con los elementos de regulación en CIS del telómero E derecho

LEONARDO CASTANEDO IBARRA (2015)

"La regulación de la expresión génica está gobernada por la unión de los factores de transcripción a los elementos de regulación en cis del genoma eucariota. En el patógeno Candida glabrata, un ejemplo de este tipo de regulación se encuentra representado por la familia de genes EPA (adhesina epitelial, por su siglas en inglés), que codifican para proteínas de la pared celular, las cuales, median la adhesión de la levadura a las células epiteliales del hospedero. En la cepa BG2, EPA1 es el único gen de la familia EPA que se expresa in vitro, mientras los 22 parálogos EPA permanecen transcripcionalmente reprimidos o silenciados. EPA1 está codificado en la región subtelomérica del cromosoma E izquierdo (tE-R), adyacente a EPA2 y EPA3. Las regiones subteloméricas de C. glabrata presentan un silenciamiento regional, no obstante, el tE-R manifiesta una combinación de silenciamiento regional y local sobre los genes EPA localizados allí. Este efecto podría deberse a la formación de bucles teloméricos (T-loop) al extremo del cromosoma, posiblemente mediado por las proteínas de unión al ADN, Abf1 y Rap1, mediante el reclutamiento de las proteínas Sir, las cuales son necesarias para el silenciamiento subtelomérico en C. glabrata. Para estudiar la función de éstas proteínas en el silenciamiento subtelomérico de C. glabrata, las etiquetamos con los epítopos c-Myc y FLAG y encontramos que las etiquetas pueden interferir con la función nativa de las proteínas. Adicionalmente, determinamos que Abf1 y Rap1 participan en la regulación de la expresión de los genes EPA de los telómeros E-R e I-R, posiblemente a través de la formación de T-loops."

"Regulation of gene expression in eukaryotes is governed by the binding of transcription factors to cis-acting elements in the genome. In the pathogenic yeast, Candida glabrata, an example of this regulation is the EPA (Epithelial Adhesin) gene family, which encodes cell surface proteins that mediate adhesion of the yeast to epithelial host cells. In the strain BG2, EPA1 is the only gene of this family that is expressed in vitro, whereas the remaining 22 EPA paralogues are transcriptionally repressed. EPA1 forms a cluster with EPA2 and EPA3 close to the right telomere of the Chromosome E (E-Rt). Contrary to the widespread silencing effect over the subtelomeric regions observed in other C. glabrata telomeres, the E-Rt exhibits a combination of regional and local silencing of the EPA genes. This effect could be due to repression at a distance, by telomere looping (T-loop), where the DNA-binding proteins Abf1 and Rap1 participate through the recruitment of the Sir proteins, which are completely necessary for the silencing at subtelomeric regions in C. glabrata. We tagged the Abf1 and Rap1 proteins with c- Myc and FLAG epitopes to study their function at Candida glabrata subtelomeric regions. We found that the tags can interfere with the normal silencing activity of the proteins and in the process, we determined that Abf1 and Rap1 participate in the regulation of the expression of EPA genes at the E-R and I-R telomeres, possibly through telomere loop formation."

Master thesis

Silenciamiento Telómeros T-loop Regulación Levadura BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA BIOLOGÍA MOLECULAR

Fine adjustment of cavity loss by sagnac loop for a dual wavelength generation¹

ARIEL FLORES ROSAS EVGENY KUZIN MIGUEL ANGEL BELLO JIMENEZ BALDEMAR IBARRA ESCAMILLA (2010)

We experimentally demonstrate a fine adjustment of cavity loss by Sagnac loop for a dual wave-length generation. The single or dual wavelengths are obtained by controlling the losses on both cavities through a fiber optical loop mirror (FOLM). Wavelength separation on the dual laser is 0.98 nm. The dual or single wavelength is obtained by changes in temperature in the order of 10⁻¹°C around the maximum in the FOLM. Also, we investigate energy fluctuations on signal level saturation effect in the cavity through different pumping power that act on the EDF, where we note that from the 60-mW pumping begins to generate dual-wavelength and 80-mW stabilizes.

Article

Sagnac loop Fiber optical CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA FÍSICA ÓPTICA ÓPTICA