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Error concealment method for HEVC based on motion vector redundancy

Domingo Guzman (2018)

Several video compression standards have been produced with the aim of reducing transmission bit rates without decreasing the video quality. The High Effciency Video Coding (HEVC) standard, developed by the Joint Collaborative Team on Video Coding (JCT-VC), is characterized by delivering improved coding efficiency relative to previous standards, such as H.264/AVC. HEVC provides improved compression ratios mainly for High Definition (HD) and Ultra High Definition (UHD) video, however, such gains are associated with high increases in computational complexity and therefore long processing times. Due to the characteristics of the HEVC design, it is shown that the temporal and spatial dependency of motion information is higher than in the H.264/AVC standard, producing a lack of robustness against the loss of information caused by transmission errors or data losses in storage. Based on the above, current error concealment methods might not be prepared to work with these new features. This work addresses the development of an Error Concealment (EC) method for improving the resilience of the HEVC standard, backing up a set of intra coded Coding Units (CUs), including its corresponding motion information and partitioning. CUs are selected by choosing quad-tree structures and PU shapes with lower partitioning depth, because losing larger structures represent a signi_cant degradation of the visual quality, and then transmitted as redundancy. Redundant information is embedded in a reversible way introducing no visible distortion within Discrete Cosine Transform (DCT) coefficients. A lost CU could be restored using the backup structure and motion information at the decoding stage or could be restored through a generic structure choosing between neighboring candidates through the use of the Outer Boundary Matching Algorithm (OBMA), in situations where the coding unit and its backup information gets lost. Simulations show that the proposed method can efficiently restore lost CUs using redundant motion information, improving error resilience up to 3 dB in Peak

Signal-to-Noise Ratio (PSNR) and quality when compared to the related proposal in state of the art at the frame level, and up to 4 dB compared to the original HEVC standard without redundant embedded information.

Master thesis

HEVC Error concealment Coding unit Motion vector Inter coding CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA MATEMÁTICAS CIENCIA DE LOS ORDENADORES DISPOSITIVOS DE CONTROL

Stabilization of bed Inclination angle in rotary drums by using computer vision

CLAUDIA PATRICIA FLORES GUTIERREZ ANTONIO REYES OBANDO OCTAVIO ISRAEL RENTERIA VIDALES Alejandro Ricardo Femat Flores (2018)

"Computer vision systems have had great importance in research of different industrial processes. Videos and photographs have been used to characterize the bed behavior in a rotary drum; in this way, the bed motion, repose angles, trajectories, and particle velocity can be determined This work shows the development of a computer vision system that measures the bed inclination angle in industrial rotary drums. The purpose of the vision system is to capture the images when the angular velocity on the drum changes. Eventually, with the data measured during the two experiments in industrial rotary drums, we have identified two input-output models representing the slumping motion. Based on the control objective, we considered two approaches: regulation and tracking PI and PII2 controllers have been designed to show that a bed inclination angle can be stabilized for rolling motion considering plants that represent slumping motion and the inclination angle as the measured variable."

Article

Rotating drum Granular material Rolling bed Kilns Flow Motion Particles Behavior Solids Transition INGENIERÍA Y TECNOLOGÍA INGENIERÍA Y TECNOLOGÍA

Bases normales óptimas sobre campos finitos

Vither Franco Rojas Tarquino (2014)

Instituto de Física y Matemáticas. Facultad de Ciencias Físico Matemáticas. Unidad Morelia del Instituto de Matemáticas de la UNAM. Programa Conjunto de Maestría en Matemáticas

Consider the finite field Fqn. This field can be viewed as a n-dimensional vector space over Fq, thus, it has a basis formed by n elements of Fqn. A basis of the form {α, αq , αq2 , ..., αqn−1 } with α ∈ Fqn is called normal basis of Fqn over Fq . When an element is identified by its coordinate vector in this basis, its q-th power has the same vector, but shifted to the right one position. Multiplication with respect to a normal basis can be defined in terms of a certain bilinear form represented by a matrix. We define the complexity of that normal basis to be the number of nonzero entries in this matrix. An argument due to Mullin et al. shows that this matrix has at least 2n − 1 non zero entries. If it contains exactly 2n − 1 non zero entries, then the normal basis is said to be optimal. In this dissertation is explained and described the stage of normal bases in finite fields. Normal Bases Theorem is showed and the normal elements of Fqn over Fq were characterized. The argument due to Mullin et al. is exposed. On the one hand, the criteria for constructing optimal normal bases is analyzed, on the other hand the classification of all optimal normal bases is explained. The proofs of results were detailed, the facts that are assumed true in original sources were isolated in lemas, which were shown for get clear proofs. An equivalent and alternative formulation is proposed of Theorem due S. Gao, which allows to construct optimal normal bases and low complexity normal bases. Finally, explanatory observations about the objects into the statement of this Theorem are made in the form of propositions.

Consideremos el campo finito Fqn . Dicho campo puede verse como un espacio vectorial de dimensión n sobre Fq, as ́ı, tiene una base formada por n elementos de Fqn. Una base de la forma {α,αq,αq2,...,αqn−1} con α ∈ Fqn se llama base normal de Fqn sobre Fq. Cuando un elemento se identifica con su vector de coordenadas en esta base, su potencia q-ésima tiene el mismo vector pero rotado una posición a la derecha. La multiplicación con respecto a una base normal puede ser definida en términos de una cierta forma bilineal representada por una matriz, se define entonces la complejidad de esa base normal como el número de entradas distintas de cero en dicha matriz. Un argumento debido a Mullin et al. muestra que dicha matriz tiene al menos 2n − 1 entradas distintas de cero. Cuando tiene exactamente 2n − 1 entradas distintas de cero, la base normal se dice que es ́optima. En esta tesina se explica y describe el escenario de las bases normales en campos finitos. Se prueba el Teorema de la Base Normal y se caracteriza a los elementos normales de Fqn sobre Fq. Se expone el argumento de Mullin et al., se explican por un lado los criterios para construir bases normales ́optimas y por otro lado su clasificación.
Las pruebas de los resultados fueron detalladas, los hechos que en las fuentes originales se dan por sentados se aislaron en lemas, los cuales fueron demostrados para conseguir pruebas claras. Se propone una formulación equivalente y alternativa al Teorema de S. Gao que permite construir bases normales ́optimas y de baja complejidad, además se hacen observaciones aclaratorias en la forma de proposiciones, relativas a los objetos que participan en el enunciado de dicho Teorema.

Master thesis

CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA IFM-M-2014-0197 Base Vector Matriz

Estudio de la interacción de la simbiosis micorrízica arbuscular en plantas infectadas con Tobacco mosaic virus

ESMERALDA JUDITH CRUZ GUTIERREZ (2013)

Tesis (Doctorado en Ciencias, especialista en Edafología).- Colegio de Postgraduados, 2013.

Este estudio evaluó la respuesta fisiológica en plantas de jitomate (Solanum lycopersicum L.) y de tabaco (Nicotiana tabacum L.) inoculadas con un consorcio de hongos micorrízicos arbusculares (HMA) o con Rhizophagus intraradices, e infectadas con el Tobacco mosaic virus (TMV). Además, se analizó la posible transferencia de partículas virales a través de las hifas de los HMA de una planta enferma a una planta sana. Este trabajo se dividió en dos capítulos, el primer capítulo describe el crecimiento, el contenido de clorofila total, la determinación de la fosfatasa ácida de la raíz, el contenido total de compuestos fenólicos, la actividad antioxidante total, y la colonización micorrízica, en plantas de jitomate colonizada por R. intraradices e infectada por el TMV. El segundo capítulo describe la posible transferencia del TMV de una planta enferma de tabaco (Nicotiana tabacum L.) a una planta sana a través de las hifas de los HMA, y evaluando el crecimiento de la planta, el contenido de clorofila total, la actividad de la fosfatasa ácida de la raíz, el contenido total de compuestos fenólicos, la actividad antioxidante total, la colonización micorrízica, y la detección de virus en hojas y raíz, y en esporas de los HMA por RT-PCR. En general, los resultados mostraron que los HMA no atenuaron el daño ni los síntomas causados por la enfermedad del TMV en las plantas de jitomate y tabaco. Las estructuras de los HMA podrían transmitir al TMV de una planta enferma a una planta sana por el contacto cercano de los HMA con las células de la raíz de una planta infectada con el virus. _______________ STUDYING THE INTERACTION BETWEEN THE ARBUSCULAR MYCORRHIZAL PLANTS INFECTED WITH THE Tobacco mosaic virus. ABSTRACT: This study evaluated the physiological responses of tomato (Solanum lycopersicum L.) and tobacco (Nicotiana tabacum L.) plants inoculated with a consortium of arbuscular mycorrhizal fungi (AMF) or with Rhizophagus intraradices, and infected with the Tobacco mosaic virus (TMV). The possible transference of viral particles throughout via mycelium of AMF from diseased plants to healthy plants was also analyzed. This research was divided in two chapters. First chapter describes the growth, total chlorophyll content, acid root phosphatase, total content of phenolic compounds, total antioxidant activity, and the mycorrhizal colonization of tomato plants inoculated with R. intraradices and/or infected with TMV. Second chapter describes the transference of TMV from a diseased tobacco plants (Nicotiana tabacum L.) to healthy ones via AMF mycelium, also evaluates the growth, the total chlorophyll content, acid root phosphatase, total content of phenolic compounds, total antioxidant activity, the mycorrhizal colonization, and the virus detection in leaves and roots, and in AMF spores by RT-PCR method. Overall, results showed that AMF did not attenuate either damage or symptoms caused by TMV in tomato or tobacco plants. AMF structures may harbor and transmit the TMV from diseased to healthy plants due to direct contact of AMF with roots of plants infected with this virus.

Doctoral thesis

Interacción virus-hongo Vector Solanáceas Fisiología Micorriza Virus-fungi interactions Vector Solanaceae Mycorrhiza Edafología Doctorado CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA

Motion Poster: Diseño metodológico y aplicación para la promoción de eBooks

JESUS DANIEL ESTRADA TAPIA (2016)

El presente documento de investigación denominado Motion Poster: Diseño Metodológico y aplicación para la promoción de eBooks, tiene como premisa la pertinencia y viabilidad del Motion Poster (MP) como recurso hacia la promoción de eBooks; y como objetivo, proponer un diseño metodológico para la realización de un MP, el cual se caracteriza por ser un poster en movimiento, exclusivo para el ámbito cinematográfico. Sin embargo, en este documento de investigación se realiza la propuesta para el ámbito cinematográfico. Sin embargo, en este documento de investigación se realiza la propuesta para el ámbito literario digital, es decir, para los eBooks o libros electrónicos, que sin duda tienen una caracterización y difusión específica, asi como un público que cada vez más, va en aumento, ya que poco a poco las generaciones nativas digitales están introduciéndose en la lectura con ayuda de esta pieza editorial.

Master thesis

Motion poster promoción eBooks CIENCIAS SOCIALES

Dynamics of subtropical vertical motions over the Americas during El Niño boreal winters

VICTOR ORLANDO MAGAÑA RUEDA Tercio ambrizzi (2005)

On the average, during boreal winter (December through February), the occurrence of El Niño/Southern Oscillation (ENSO) results in enhanced or diminished precipitation in various regions of the Americas. Anomalous convective activity in the central-eastern Pacific forces quasi-stationary Rossby waves that follow paths to the Northern and Southern hemispheres. The so-called Pacific-North American (PNA) pattern results in ascending motion and enhanced precipitation over California and the Gulf of Mexico. The PNA also affects the Caribbean Sea by inhibiting winter tropical convection due to subsidence. In the Southern Hemisphere (SH), a weak quasi-stationary wave train is observed over southeast South America that results in enhanced ascending motion and precipitation. Over the equatorial region, the descending branch of a stationary Kelvin wave inhibits convective activity over northeastern Brazil and other parts of northern South America. However, there are well known differences in the El Niño signal from one event to another in what is known as inter-ENSO variability. Through quasi-geostrophic analyses, the anomalous vertical motions associated with the quasi-stationary Rossby waves may be separated from those associated with the stationary equatorial Kelvin wave. Ray tracing analyses show that quasi-stationary Rossby waves with wavenumbers 3, 4 and 5 explain part of the spatial structure of the circulation anomalies over the subtropical Americas related to the upward and downward vertical motions. The phase and amplitude of these waves depend on the structure of the mean zonal flow and the location of the anomalous convective forcing, as concluded from sensitivity experiments with a baroclinic model. An error in the simulated intensity of the mean zonal flow may result in phase shifts of the vertical motions and consequently, on errors in the simulated precipitation anomalies over the subtropical Americas. Some General Circulation Models, such as the NCAR Community Climate Model (CCM3) have this problem. Even more, a systematic bias is found in the CCM3, with weaker (stronger) than observed anomalies in extratropical (tropical) vertical motions, and consequently, in weaker (stronger) than observed precipitation anomalies. The implication of these analyses for seasonal climate predictions at a regional level in the subtropical Americas is discussed.

Article

CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA ENOS Rossby waves vertical motion precipitation

Fusión de múltiples cámaras móviles para seguimiento de objetos

JORGE EDUARDO XALTENO ALTAMIRANO (2010)

In this work, a solution for the object tracking with moving cameras problem is presented; data fusion based on the Dezert-Smarandache Theory is used; the sensor movement is used to observe partially occluded objects.

The movement of the cameras is made in two different ways, named, linear movement and circular movement. In the linear movement, the cameras are set perpendicularly form each other; in the circular movement, the cameras are set around the scene and they turn around the center of the scene.

The movement of the cameras represents an advantage over the systems that use fixed cameras, because the movement of the cameras is used to observe partially or totally occluded objects, as in this work. As a difference from the systems with fixed cameras in which is necessary to use any method of prediction in order to solve the occlusion, with moving cameras this solution is reached without using any other method but the movement of the cameras itself.

During the movement of the cameras, an accumulation of evidence is done, this accumulation aloud to have a larger certainty of the object in order to take a more accurate decision.

Finally, a comparison between the results of the fusion based on Dezert-Smarandace theory and the Bayesian fusion is presented; there were made experiments in order to determine which approach was giving better results; for the evaluation of the experiments there were used rates of false and true positives, giving as a result that the Dezert-Smarandache Theory achieves better results.

El siguiente trabajo se enfoca en hacer seguimiento de objetos utilizando sensores en movimiento y fusión basada en la teoría Dezert-Smarandache para fusión de información; el movimiento de los sensores es aprovechado para lograr observar objetos parcialmente ocultos.

El movimiento de las cámaras se realiza de dos formas distintas, movimiento lineal y movimiento circular. En el movimiento lineal los sensores se mueven en línea recta y se sitúan perpendicularmente uno del otro; en el movimiento circular los sensores están dispuestos alrededor del centro de la escena y giran sobre este centro, describiendo el movimiento circular.

El movimiento de los sensores es una ventaja sobre los sistemas que utilizan sensores estáticos, en este trabajo se utiliza el movimiento de los sensores para observar objetos parcial o totalmente ocultos. A diferencia de los sistemas con sensores estáticos donde es necesario utilizar algún método de predicción para resolver la oclusión, con los sensores en movimiento esta solución se logra sin hacer uso de otro método más que el mismo movimiento de los sensores.

Durante el movimiento de los sensores se realiza una acumulación de evidencia, esta acumulación permite tener una mayor certeza sobre la observación del objeto y así tomar una decisión más precisa.

Finalmente, se presenta una comparación entre los resultados de la fusión utilizando la teoría Dezert-Smarandache y la fusión Bayesiana, se realizaron experimentos para determinar que enfoque daba mejores resultados, para la evaluación de estos experimentos se utilizaron tazas de falsos y verdaderos positivos, dando como resultado que la teoría Dezert-Smarandache da mejores resultados.

Master thesis

Cameras Motion measurement Tracking CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA MATEMÁTICAS CIENCIA DE LOS ORDENADORES

Modelo flexible de movimiento de torso, brazo, antebrazo y muñeca

VICTOR LOBATO RIOS (2016)

Human motion analysis is an open research area that focuses on explaining,

by using different kind of sensors, the movements made by a person

and how they are accomplished. An important task of this research area is

proposing computational models able to represent human motion.

People move differently from each other, and some factors such as the

age or loss of physical abilities change their motion patterns, for that, it

is necessary to develop, on one hand flexible methods and motion models;

i.e. able to represent the movements of several groups of people, and on the

other hand simple ones; i.e. based on unsophisticated instruments, such as

wearable systems.

The main goal of this research is proposing and implementing a flexible

motion model based on signals of wireless inertial sensors and an electromyograph

to represent the motion of the trunk, arm, forearm and wrist of

a person with or without motion impairments. This motion model could

be used as a tool to analyze in detail the motion of people to determine

quantitatively the differences in their range of motion.

The developed model represents the motion of ten degrees of freedom of

the body: three of the trunk, three of the shoulder, two of the elbow and

two of the wrist. Our motion model is divided into two parts, on one hand,

the first part consists of a kinematic model that uses the information given

by three inertial measurement units to represent the motion of the trunk,

arm and forearm. On the other hand, the second part consists of a model

based on an ensemble of classifiers able to represent the motion of the wrist

by analyzing characteristics obtained through the electromyographic signals

of the forearm.

Two experiments were conducted in order to validate both parts of us

motion model. For the kinematic model, a reaching task was used as case

study and movement trajectories were compared. Namely, the trajectories of

the nape, arm and hand of five healthy people and one apoplexy patient obtained

through our motion model and through an optical system comprising eight cameras used as our ground truth. For the model based on the ensemble

of classifiers six decision trees were generated. A classification task of

the movements of the wrist of fifteen healthy people was accomplished using

two different data distributions, a random distribution and a distribution

based on individuals.

El análisis de movimiento humano es un área de investigación abierta

donde se busca explicar, a partir de diversos tipos de sensores, qué movimientos

realiza una persona y cómo los realiza. Una tarea importante de esta

área de investigación radica en proponer modelos computacionales capaces

de representar el movimiento humano.

La manera de moverse varía de una persona a otra, y algunos factores

como la edad o la pérdida de capacidades físicas modifican los patrones de

movimiento, por ello, es necesario desarrollar métodos y modelos de movimiento

flexibles, por un lado; es decir, con capacidad de capturar el movimiento

de varios grupos de personas, y simples por otro lado; es decir, que se

basen en instrumentos no sofisticados, como lo son los sistemas “vestibles".

El objetivo de esta investigación es proponer e implantar un modelo

de movimiento flexible basado en señales de sensores inerciales y un electro miógrafo inalámbricos para representar el movimiento del torso, brazo,

antebrazo y muñeca de una persona que tenga o no limitaciones de movimiento.

Este modelo de movimiento podría servir como una herramienta

para analizar de forma detallada el movimiento de las personas y así determinar

de manera cuantitativa las diferencias en sus grados de movilidad.

El modelo desarrollado representa el movimiento que generan diez grados

de libertad del cuerpo: tres del torso, tres del hombro, dos del codo y dos

de la muñeca. Nuestro modelo de movimiento se divide en dos partes, la

primera es un modelo cinemático que utiliza la información de tres unidades

de medición inercial para representar el movimiento del torso, el brazo y

el antebrazo. Y, por otra parte, se cuenta con un modelo basado en un

ensamble de clasificadores, el cual se encarga de representar los movimientos

generados por la muñeca al analizar características extraídas de las señales

electromiografícas del antebrazo.

Se realizaron experimentos para validar las dos partes de nuestro modelo

de movimiento. Para el modelo cinemático se utilizó una tarea de alcance

como caso de estudio y se compararon las trayectorias del movimiento de la nuca, del brazo y de la mano de cinco personas sanas y de un paciente que

sufrió una apoplejía obtenidas por medio de nuestro modelo cinemático y por

medio de un sistema óptico de ocho cámaras que sirve como nuestro ground

truth.

Master thesis

Motion model Wearable sensors Kinematic model Ensamble of classifiers CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA MATEMÁTICAS CIENCIA DE LOS ORDENADORES

Ion–laser interactions: The most complete solution

Héctor Manuel Moya Cessa FRANCISCO SOTO EGUIBAR JOSE MANUEL VARGAS MARTINEZ (2012)

Trapped ions are considered one of the best candidates to perform quantum information processing. By interacting them with laser beams they are, somehow, easy to manipulate, which makes them an excellent choice for the production of nonclassical states of their vibrational motion, the reconstruction of quasiprobability distribution functions, the production of quantum gates, etc. However, most of these effects have been produced in the so-called low intensity regime, this is, when the Rabi frequency (laser intensity) is much smaller than the trap frequency. Because of the possibility to produce faster quantum gates in other regimes it is of importance to study this system in a more complete manner, which is the motivation for this contribution. We start by studying the way ions are trapped in Paul traps and review the basic mechanisms of trapping. Then we show how the problem may be completely solved for trapping states; i.e., we find (exact) eigenstates of the full Hamiltonian. We show how, in the low intensity regime, Jaynes–Cummings and anti-Jaynes–Cummings interactions may be obtained, without using the rotating wave approximation and analyze the medium and high intensity regimes where dispersive Hamiltonians are produced. The traditional approach (low intensity regime) is also studied and used for the generation of non-classical states of the vibrational wavefunction. In particular, we show how to add and subtract vibrational quanta to an initial state, how to produce specific superpositions of number states and how to generate NOON states for the two-dimensional vibration of the ion. It is also shown how squeezing may be measured. The time dependent problem is studied by using Lewis–Ermakov methods. We give a solution to the problem when the time dependence of the trap is considered and also analyze a specific (artificial) time dependence that produces squeezing of the initial vibrational wave function. A way to mimic the ion–laser interaction via classical optics is also introduced.

Article

Ion–laser interactions Vibrational motion CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA FÍSICA ÓPTICA ÓPTICA

Characterization of chloroplast region rrn16-rrn23S from the tropical timber tree Cedrela odorata L. and de novo construction of a transplastomic expression vector suitable for Meliaceae trees and other economically important crops

LUISA ALHUCEMA LOPEZ OCHOA MAX MIZRAIM APOLINAR HERNANDEZ YURI JORGE JESUS PEÑA RAMIREZ (2015)

The forest tree Spanish cedar (Cedrela odorata L.) is well-known for its high-value timber; however, this species is attacked by the shoot borer (Hypsipyla grandella) during its early years of development, resulting in branched stems and making the plants useless for high-quality wood production. The generation of resistant varieties expressing entomotoxic proteins may be an alternative to pesticide treatments. The use of plastid transformation rather than nuclear transformation should be used because it reduces the risk of transgene dissemination by pollen. Chloroplast transformation vectors require an expression cassette flanked by homologous plastid sequences to drive plastome recombination. Thus, C. odorata plastome sequences are a prerequisite. The rrn16-rrn23 plastome region was selected, cloned, and characterized. When the sequence identity among the rrn16-rrn23 regions from C. odorata and Nicotiana tabacum was compared, 3 inDels of 240, 104, and 39 bp were found that might severely affect transformation efficiency. Using this region, a new transformation vector was developed using pUC19 as a backbone by inserting the rrn16-trnI and trnA-rrn23 sequences from C. odorata and adding 2 independent expression cassettes into the trnI-trnA intergenic region, conferring spectinomycin resistance, the ability to express the gfp reporter gene, and a site that can be used to express any other gene of interest.

Article

CHLOROPLAST TRANSFORMATION EXPRESSION VECTOR FLANKING REGIONS PLASTOME SEQUENCE TROPICAL TREE BIOTECHNOLOGY BIOLOGÍA Y QUÍMICA BIOLOGÍA Y QUÍMICA