Academic literature on the topic '[519.1'
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Journal articles on the topic "[519.1"
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Rebenko, O. L. "Нове найпростіше доведення формули келі та зв’язок із рівняннями Кірквуда – Зальцбурга." Ukrains’kyi Matematychnyi Zhurnal 74, no. 10 (November 27, 2022): 1441–44. http://dx.doi.org/10.37863/umzh.v74i10.7156.
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Stegantseva, P. G., and A. V. Skryabina. "Топології на -елементній множині, узгоджені з топологіями близькими до дискретних на -елементній множині." Ukrains’kyi Matematychnyi Zhurnal 73, no. 2 (February 22, 2021): 238–48. http://dx.doi.org/10.37863/umzh.v73i2.6174.
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УДК 519.1 В роботi топологiї на скiнченнiй множинi описуються неспадною послiдовнiстю невiд’ємних цiлих чисел (вектором топологiї). Дослiджуються -топологiї на -елементнiй множинi, якi iндукують на -елементнiй множинi топологiї з (цi iндукованi топологiї називають близькими до дискретної). Символом позначено кiлькiсть вiдкритих множин у топологiї. Знайдено вигляд вектора -топологiй з , якi описано в роботах Stanley i Kolli, i значення , для яких не iснують -топологiї з вiдкритими множинами. Описано всi помiченi -топологiї i знайдено їхню кiлькiсть для кожного . Показано iснування таких значень , що жодна -топологiя з вiдкритими множинами не iндукує на -елементнiй множинi близьку до дискретної топологiю.
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John, J., and M. S. Malchijah Raj. "Graphs with large Steiner number." Ukrains’kyi Matematychnyi Zhurnal 76, no. 5 (June 2, 2024): 719–27. http://dx.doi.org/10.3842/umzh.v76i5.7409.
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UDC 519.1 In 2002, Gary Chartrand and Ping Zhang [<em>The Steiner number of a graph,</em> Discrete Math., <strong>242</strong>, 41--54 (2002)] characterized the connected graphs G of order p ≥ 3 with Steiner number p , p - 1 , or 2. In our paper, we characterize all connected graphs G of order p ≥ 4 with Steiner number s ( G ) = p - 2 . In addition, we obtain some sharp Nordhaus–Gaddum bounds for the Steiner number of connected graphs whose complement is also connected.
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Raucci, Gaetana, Camila Pachêco-Pereira, Maryam Elyasi, Fabrizia d’Apuzzo, Carlos Flores-Mir, and Letizia Perillo. "Short- and long-term evaluation of mandibular dental arch dimensional changes in patients treated with a lip bumper during mixed dentition followed by fixed appliances." Angle Orthodontist 86, no. 5 (January 15, 2016): 753–60. http://dx.doi.org/10.2319/073015-519.1.
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ABSTRACT Objective: To evaluate short- and long-term mandibular dental arch changes in patients treated with a lip bumper during the mixed dentition followed by fixed appliances, compared with a matched control sample. Materials and Methods: Dental casts and lateral cephalograms obtained from 31 consecutively treated patients before (T0) and after (T1) lip bumper, after fixed appliances (T2), and a minimum of 3 years after fixed appliances (T3) were analyzed. The control group was matched as closely as possible. Arch width, arch perimeter, arch length, and incisor proclination were evaluated. Repeated measures ANOVA was used to analyze changes in measurements over all four time points between treatment and control groups. Results: Arch widths and crowding were always significantly different except at T2−T1. At T1−T0, only crowding decreased 3.2 mm while intercanine, interpremolar, and intermolar widths increased by 3.8, 3.3, and 3.9 mm, respectively. Changes at T3−T2 showed a significant decrease of 2.1 mm for crowding and an increase of 3.5, 2.9, 2.7, and 0.8 mm for intercanine, interpremolar, and intermolar widths and arch perimeter, respectively. Finally, at T3−T0, the reduction in crowding of 5.03 mm was significant and clinically important in the treated group. The differences between intercanine, interpremolar, and intermolar widths were also significant (2.1, 3.8, and 3.6 mm, respectively). All those differences favored the treated group. Conclusions: Mandibular dental arch dimensions were significantly changed after lip bumper treatment. At follow-up, all arch widths were slightly decreased, generating an increase of 0.4 mm in crowding, considered clinically irrelevant. Overall changes remained stable after an average 6.3-year follow-up.
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Premaraj, Sundaralingam, Isabela Souza, and Thyagaseely Premaraj. "Mechanical loading activates β-catenin signaling in periodontal ligament cells." Angle Orthodontist 81, no. 4 (July 2011): 592–99. http://dx.doi.org/10.2319/090310-519.1.
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Muller, Mathieu, Fanja Rabenoelina, Patrick Balaguer, Dominique Patureau, Karin Lemenach, Hélène Budzinski, Damia Barceló, et al. "CHEMICAL AND BIOLOGICAL ANALYSIS OF ENDOCRINE-DISRUPTING HORMONES AND ESTROGENIC ACTIVITY IN AN ADVANCED SEWAGE TREATMENT PLANT." Environmental Toxicology and Chemistry 27, no. 8 (2008): 1649. http://dx.doi.org/10.1897/07-519.1.
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de Jesus Silva, Raquel, Lysandro Pinto Borges, Lucindo José Quintans-Júnior, Camila Ferezin Resende, Flávio Adsuara Cadegiani, João Henrique Gomes, and Renata Rebello Mendes. "Acute effects of a typical rhythmic gymnastic training session on physiological parameters in Olympic athletes." Kinesiology 54, no. 2 (2022): 278–87. http://dx.doi.org/10.26582/k.54.2.9.
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The aim of this study was to evaluate the effects of a day with two separate training sessions (morning and afternoon) of rhythmic gymnastics on erythrocytes, leukocytes, muscle damage, oxidative stress, and hydration of Brazilian team [age 17.7 (±1.1) years; body height 165 (±0.5) cm; body mass 49.7 (±4.2) kg]. Heart rate and session-ratings of perceived exertion were used to monitor training intensity. Blood samples were collected immediately before (M1) and after (M2) the training day for analyzing erythrocytes, leukocytes, plasma creatine kinase activity, lactate dehydrogenase, alanine aminotransferase, aspartate aminotransferase, ferric reducing ability plasma, thyroid-stimulating hormone, and free T4. Saliva was collected for cortisol analysis. After 24 hours rest (M3), blood collection was performed to analyze creatine kinase and lactate dehydrogenase. The moderate-intensity training day induced significant elevations of total leukocytes (5,163.3 to 9,617.8), lymphocytes (1,752.7 to 2,729.7), neutrophils (2,873.9 to 6,163.6), monocytes (255.7 to 519.1), platelets (280,000.0 to 300,666.7), aspartate aminotransferase (13.1 to 25.6), lactate dehydrogenase (102.5 to 249.1), thyroid-stimulating hormone (1.0 to 3.2), and ferric reducing ability plasma (136.8 to 165.4), as well as significant reductions in red cells (4,691,111.1 to 4,497,777.8), hematocrit (42.1 to 39.3), and hemoglobin (12.9 to 12.5) at M2. There were also significant increases in creatine kinase (144.2 to 519.3) and lactate dehydrogenase (102.5 to 538.2) at M3. The average dehydration rate was 1.3%. A moderate-intensity day of training in rhythmic gymnastics of 8h21min duration caused hemolysis, leukocytosis, muscle damage, redox status perturbations, and insufficient hydration status. These findings show that athletes are exposed to physiological vulnerabilities that can possibly harm their performance and health.
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Chen, Wei, Guangfu Yin, Zai Feng, and Xiaoming Liao. "Effect of Powder Feedstock on Microstructure and Mechanical Properties of the 316L Stainless Steel Fabricated by Selective Laser Melting." Metals 8, no. 9 (September 17, 2018): 729. http://dx.doi.org/10.3390/met8090729.
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Additive manufacturing by selective laser melting (SLM) was used to investigate the effect of powder feedstock on 316L stainless steel properties include microstructure, relative density, microhardness and mechanical properties. Gas atomized SS316L powders of three different particle size distribution were used in this study. Microstructural investigations were done by scanning electron microscopy (SEM). Tensile tests were performed at room temperatures. Microstructure characterization revealed the presence of hierarchical structures consisting of solidified melt pools, columnar grains and multiform shaped sub-grains. The results showed that the SLM sample from the fine powder obtained the highest mechanical properties with ultimate tensile strength (UTS) of 611.9 ± 9.4 MPa and yield strength (YS) of 519.1 ± 5.9 MPa, and an attendant elongation (EL) of 14.6 ± 1.9%, and a maximum of 97.92 ± 0.13% and a high microhardness 291 ± 6 HV0.1. It has been verified that the fine powder (~16 μm) could be used in additive manufacturing with proper printing parameters.
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Xu, Zhe, Jian Qiang Li, and Guo Cai Zhang. "Synthesis and Properties of Microencapsulated Solid Paraffin Phase Change Materials." Key Engineering Materials 519 (July 2012): 1–5. http://dx.doi.org/10.4028/www.scientific.net/kem.519.1.
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To prepare the phase change materials for efficient low-temperature latent heat storage, microcapsules with commercial solid paraffin were synthesized by using in-situ polymerization process. Liquid paraffin was used first as core materials since it facilitates the direct observation of containment by the shell of melamine-formaldehyde resin (MF resin), and examines easily the optimal synthesizing condition. The effects of emulsion processes, pre-polymerization conditions, shell material content and reaction time on the quality of microcapsules were investigated. The experimental investigations show that the optimal process of synthesizing liquid paraffin microcapsules is adoptable to that of solid paraffin microcapsules. The as-prepared solid paraffin microcapsules show high quality. The microcapsules surface was smooth and dense, and be free of any adhesion. The measurements show that in the microcapsules solid paraffin was well encapsulated by MF resin. The microcapsule size was almost within the range of 6~33 μm and most intense distribution at 23 μm. DSC measurements gave two endothermic peaks with initial phase change temperature at 35°C and 50°C respectively, and the total enthalpy was above 134 J/g.
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Oh, Tak, Jung-Won Hwang, Young-Tae Jeon, and Sang-Hwan Do. "Perioperative Cumulative Fluid Balance and Its Association with an Increase in Costs after Major Surgery." Journal of Clinical Medicine 7, no. 9 (August 21, 2018): 227. http://dx.doi.org/10.3390/jcm7090227.
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Positive fluid balance (FB) during the perioperative period may increase the incidence of postoperative complications, which may lead to longer hospitalization and higher hospital costs. However, a definitive association between positive FB and hospital costs has not yet been established. This retrospective observational study examined the association between perioperative FB and hospital costs of patients who underwent major surgical procedures. Medical records of patients who underwent major surgery (surgery time >2 h, estimated blood loss >500 mL) from January 2010 to December 2017 were analyzed to determine the associations between calculated FB (%, total input fluid—output fluid in liter/weight (kg) at admission) and total hospital cost ($). The analysis included medical data of 7010 patients. Multivariable linear regression analyses showed that a 1% increase in FB in postoperative day (POD) 0 (24 h), 0–1 (48 h), 0–2 (72 h), and 0–3 (96 h) significantly increased the total cost by $967.8 (95% confidence interval [CI]: 803.4–1132.1), $688.8 (95% CI: 566.3–811.2), $591 (95% CI: 485.7–696.4), and $434.2 (95% CI: 349.4–519.1), respectively (all p < 0.001). Perioperative cumulative FB was positively associated with hospital costs of patients who underwent major surgery.
Dissertations / Theses on the topic "[519.1"
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Villamizar, Vergel Michael Alejandro. "Efficient approaches for object class detection." Doctoral thesis, Universitat Politècnica de Catalunya, 2012. http://hdl.handle.net/10803/96775.
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La visión por computador y más específicamente el reconocimiento de objetos han demostrado en los últimos años un impresionante progreso que ha llevado a la aparición de nuevas y útiles tecnologías que facilitan nuestras actividades diarias y mejoran ciertos procesos industriales. Actualmente, nosotros podemos encontrar algoritmos para el reconocimiento de objetos en computadores, videocámaras, teléfonos móviles, tablets o sitios web para la realización de ciertas tareas específicas tales como la detección de caras, el reconocimiento de gestos y escenas, la detección de peatones, la realidad aumentada, etc.
No obstante, estas aplicaciones siguen siendo problemas abiertos que cada año reciben más atención por parte de la comunidad de visión por computador. Esto se demuestra por el hecho de que cientos de artículos abordando estos problemas son publicados en congresos internacionales y revistas anualmente. Desde una perspectiva general, los trabajos más recientes intentan mejorar el desempeño de clasificadores, hacer frente a nuevos y más desafiantes problemas de detección, y a aumentar la eficiencia computacional de los algoritmos resultantes con el objetivo de ser implementados comercialmente en diversos dispositivos electrónicos. Aunque actualmente, existen enfoques robustos y confiables para la detección de objetos, la mayoría de estos métodos tienen un alto coste computacional que hacen imposible su aplicación en tareas en tiempo real. En particular, el coste computacional y el desempeño de cualquier sistema de reconocimiento está determinado por el tipo de
características, método de reconocimiento y la metodología utilizada para localizar los objetos dentro de las imágenes. El principal objetivo de estos métodos es obtener sistemas de detección eficaces pero también eficientes.
A través de esta tesis diferentes enfoques son presentados para abordar de manera eficiente y discriminante la detección de objetos en condiciones de imagen diversas y difíciles. Cada uno de los enfoques propuestos ha sido especialmente diseñado y enfocado para la detección de objetos en circunstancias distintas, tales como la categorización de objetos, la detección bajo rotaciones en el plano o la detección de objetos a partir de múltiples vistas. Los métodos propuestos combinan varias ideas y técnicas para la obtención de detectores de objetos que son tanto altamente discriminantes como eficientes. Esto se demuestra experimentalmente en varias bases de datos del estado del arte donde los resultados alcanzados son competitivos al ser contrastados con otros métodos recientes. En concreto, esta tesis estudia y desarrolla características rápidas, algoritmos de aprendizaje, métodos para reducir el coste computacional de los clasificadores y representaciones de imagen integral que permiten un mejor cálculo de las características.Computer vision and more specifically object recognition have demonstrated in recent years an impressive progress that has led to the emergence of new and useful technologies that facilitate daily activities and improve some industrial processes. Currently, we can find algorithms for object recognition in computers, video cameras, mobile phones, tablets or websites, for the accomplishment of specific tasks such as face detection, gesture and scene recognition, detection of pedestrians, augmented reality, etc. However, these applications are still open problems that each year receive more attention in the computer vision community. This is demonstrated by the fact that hundreds of articles addressing these problems are published in international conferences and journals annually. In a broader view, recent work attempts to improve the performance of classifiers, to face new and more challenging problems of detection and to increase the computational efficiency of the resulting algorithms in order to be implemented commercially in diverse electronic devices. Although nowadays there are robust and reliable approaches for detecting objects, most of these methods have a high computational cost that make impossible their application for real-time tasks. In particular, the computational cost and performance of any recognition system is determined by the type of features, the method of recognition and the methodology used for localizing objects within images. The main objective of these methods is to produce not only effective but also efficient detection systems. Through this dissertation different approaches are presented for addressing efficiently and discriminatively the detection of objects in diverse and difficult imaging conditions. Each one of the proposed approaches are especially designed and focus on different detection problems, such as object categorization, detection under rotations in the plane or the detection of objects from multiple views. The proposed methods combine several ideas and techniques for obtaining object detectors that are both highly discriminative and efficient. This is demonstrated experimentally in several state-of-the-art databases where our results are competitive with other recent and successful methods. In particular, this dissertation studies and develops fast features, learning algorithms, methods for reducing the computational cost of the classifiers and integral image representations for speeding up feature computation.
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Martínez, Ruiz Alba. "Patent value models: partial least squares path modelling with mode C and few indicators." Doctoral thesis, Universitat Politècnica de Catalunya, 2011. http://hdl.handle.net/10803/116489.
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Two general goals were raised in this thesis: First, to establish a PLS model for patent value and to investigate causality relationships among
variables that determine the patent value; second, to investigate the performance of Partial Least Squares (PLS) Path Modelling with Mode C inthe context of patent value models.
This thesis is organized in 10 chapters. Chapter 1 presents an introduction to the thesis that includes the objectives, research scope and the
document’s structure. Chapter 2 gives an overview of the different approaches for patent value from the perspective of technological change. Definitions related to patent documents and patent indicators are provided. Chaper 3 reports on patent sample descriptions. We present criteria to retrieve data, the procedure for calculating patent indicators, and a statistical data description. Chapter 4 provides an introduction to structural equation models (SEMs) including origins, basic background and recent developments. In addition, it provides guidelines for model specification and modelling process for SEMs. Special emphasis is placed on determining the reflective or formative nature of measurement models. Chapter 5 puts forward the main PLS algorithms: NIPALS, PLS Regression and PLS Path Modelling. We present two path modelling implementations: Lohmöller and Wold’s procedures. Additionally, insights are given on procedure sensitivity to starting weight values and weighting schemes; algorithm properties, such as consistency and consistency at large; and convergence. We briefly review some PLS Path Modelling extensions and relationships with other procedures. The chapter ends by describing validation techniques. Chapter 6 provides evidence about the accuracy and precision of PLS Path Modelling with Mode C to recover true values in SEMs with few indicators per construct. Monte Carlo simulations and computational experiments are carried out to study the performance of the algorithm. Chapter 7 addresses the formulation and estimation of patent value models. This entails the identification and definition of observable and unobservable variables, the determination of blocks of manifest variables and structural relationships, the specification of a first- and a second-order models of patent value, and the models’ estimation by PLS Path Modelling. In Chapter 8, the evolution of patent value over time using longitudinal SEMs is investigated. Two set-ups are explored. The first longitudinal model includes time-dependent manifest variables and the second includes time-dependent unobservable variables. The SEMs are estimated using PLS Path Modelling. In Chapter 9, there is a description of a Two-Step PLS Path Modelling with Mode C (TsPLS) procedure to study nonlinear and interaction effects among formative constructs. Monte Carlo simulations are performed to generate data and to determine the accuracy and precision of this approach to recover true values. This chapter includes an application of the TsPLS algorithm to patent value models. Finally, in Chapter 10, we provide a summary of conclusions and future researchs.
The main contribution of this thesis is to set-up a PLS model for patent value, and around this issue, we have also contributed in two main areas: Contributions to the field of Technological Change are comprised of:
(1) Evidence on the role of the knowledge stock, technological scope and international scope as determinants of patent value and technological usefulness. A stable pattern of path coefficients was found across samples in different time periods.
(2) To conceptualize the patent value as a potential and a recognized value for intangible assets. It was also shown that the potential value of
patent is small compared to the value that is given later.
(3) Evidence for the importance of considering the longitudinal nature of the indicators in the patent value problem, especially for forward
citations, which are the most widely used indicator of patent value.
(4) To introduce a multidimensional perspective of the patent valuation problem. This novel approach may offer a robust understanding of the
different varia bles that determine patent value.
Contributions to the field of PLS Path Modelling are comprised of:
(5) Empirical evidence on the performance of PLS Path Modelling with Mode C. If properly implemented, the procedure can adequately capture
some of the complex dynamic relationships involved in models. Our research shows that PLS Path Modelling with Mode C performs
according to the theoretical framework established for PLS procedures and PLS-models (Wold, 1982; Krämer, 2006; Hanafi, 2007; Dijkstra,
2010).
(6) Empirical evidence for the consistency at large of the PLS Path Modelling with Mode A.
(7) Empirical evidence for formative outer models with few manifest variables.
(8) Empirical evidence on the performance of a Two-Step PLS Path Modelling with Mode C procedure to estimate nonlinear and interaction
effects among formative constructs.Dos objetivos general fueron planteados en esta tesis. Primero, establacer un modelo PLS para el valor de las patentes e investigar las relaciones de causalidad entre las variables que determinan el valor de las patentes. Segundo, investigar el desempeño del procedimiento Partial Least Squares (PLS) Path Modelling con Modo C en el contexto de los modelos de valor de las patentes. La tesis es organizada en 10 capítulos. El Capítulo 1 presenta una introducción a la tesis que incluye los objetivos, el alcance de la investigación y la estructura del documento. El Capítulo 2 entrega una presentación general de los diferentes enfoques para valoración de patentes desde una perspectiva del cambio tecnológico. También se entregan las definiciones necesarias relacionadas con los documentos e indicadores de patentes. El Capítulo 3 describe la muestra de patentes usada en esta investigación. Se presentan los criterios utilizados para recuperar los datos, el procedimiento seguido para calcular los indicadores de patentes y la descripción estadística de la muestra. El Capítulo 4 provee una introducción a los modelos de ecuaciones estructurales (SEMs) incluyendo orígenes, antecedentes básicos y desarrollos recientes. Además se entregan los lineamientos para la especificación de los modelos y el proceso de modelamiento para SEMs. Este capítulo discute con especial énfasis la determinación de la naturaleza reflectiva o formativa de los modelos de medida. El Capítulo 5 presenta los principales algoritmos PLS: NIPALS, Regresión PLS y PLS Path Modelling. Se presentan dos implementaciones de PLS Path Modelling: los procedimientos de Lohmöller y Wold. Adicionalmente, se analyzan resultados previos relacionados con: la sensibilidad del procedimiento al valor inicial de los vectores de pesos y el esquema de ponderación, y las propiedades del algoritmo, tales como consistencia, consistencia “at large” y convergencia. También brevemente se revisan algunas extensiones del procedimiento y su relación con otros métodos. El capítulo termina describiendo las técnicas de validación. El Capítulo 6 provee evidencia acerca de la exactitud y precisión con que PLS Path Modelling con Modo C recupera valores verdaderos en SEMs con pocos indicadores por constructo. Simulaciones Monte Carlo y experimentos computacionales son llevados a cabo para estudiar el rendimiento del algoritmo. El Capítulo 7 trata la formulación y estimación de los modelos de valoración de patentes. Esto comprende la identificación y definición de las variables observables y no observables, la determinación de los bloques de variables manifiestas y las relaciones estructurales, la especificación de los modelos de primer y segundo orden del valor de las patentes y la estimación de los mismos con PLS Path Modelling. En el Capítulo 8, la evolución del valor de las patentes a través del tiempo es investigado usando SEMs longitudinales. Dos set-ups son explorados. El primer modelo longitudinal considera variables manifiestas dependientes del tiempo y el segundo incluye variables latentes dependientes del tiempo. Los SEMs son estimados usando PLS Path Modelling. En el Capítulo 9, el procedimiento Two-Step PLS Path Modelling con Modo C (TsPLS) es implementado para estudiar los efectos no lineales y de interacción entre constructos formativos. Simulaciones Monte Carlo son llevadas a cabo para generar datos y determinar la exactitud y precisión con que este enfoque recupera valores verdaderos. Este capítulo incluye una aplicación del procedimiento a los modelos de patentes. Finalmente, el Capítulo 10 provee un resumen de las conclusiones y lineamientos para futuras investigaciones. La principal contribución de esta tesis es proponer modelos PLS para el valor de las patentes, y alrededor de este objetivo, nosotros hemos también contribuido en dos áreas principales: Contribuciones en el área del Cambio Tecnológico comprenden: (1) Evidencia empírica del rol del stock de conocimiento, el alcance tecnológico y el alcance internacional como determinantes del valor de las patentes y la utilidad tecnológica. Un patrón estable de coeficientes de trayectoria fue encontrado al estimar los modelos con muestras en diferentes periodos de tiempo. (2) Conceptualizar el valor de las patentes en un valor potencial y uno reconocido. También proveer evidencia acerca de que el valor potencial es pequeño al compararlo con el valor que las patentes adquieren con posterioridad. (3) Evidencia acerca de la importancia de considerar la naturaleza longitudinal de los indicatores en el problema de valorización de patentes, especialmente de las citas recibidas, el indicador de valor más utilizado. (4) Introducir una perspectiva multidimensional en el problema de valoración de patentes. Este nuevo enfoque puede ofrecer un entendimiento robusto de las diferentes variables que determinar el valor de las patentes. Contribuciones en el área del PLS PLS Path Modelling comprenden: (5) Evidencia empírica acerca del desempeño de PLS Path Modelling con Modo C. Apropiadamente implemetado, el procedimiento puede adecuadamente capturar algunas de las complejas relaciones dinámicas en los modelos. Nuestra investigación muestra que PLS Path Modelling con Modo C se comporta de acuerdo al marco teórico establecido para los procedimientos PLS y los modelos PLS (Wold, 1982; Krämer, 2006; Hanafi, 2007; Dijkstra, 2010). Es decir, (a) las estimaciones PLS estan siempre sesgadas, (b) las relaciones internas son subestimadas, (c) las relaciones externas son sobrestimadas, (d) el Modo A carece de la propiedad de convergencia monótona, (3) el Modo B tiene la propiedad de convergencia monótona. (6) Evidencia empírica acerca de la convergencia “at large” de PLS Path Modelling con Modo A. (7) Evidencia empírica para los modelos formativos con pocos indicadores (8) Evidencia empírica del desempeño del procedimiento Two-Step PLS Path Modelling con Modo C para estimar efectos no lineales y de interacción entre constructos formativos.
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Perarnau, Llobet Guillem. "Random combinatorial structures with low dependencies : existence and enumeration." Doctoral thesis, Universitat Politècnica de Catalunya, 2013. http://hdl.handle.net/10803/362940.
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En aquesta tesi s'estudien diferents problemes en el camp de la combinatòria i la teoria de grafs, utilitzant el mètode probabilístic. Aquesta tècnica, introduïda per Erdős , ha esdevingut una eina molt potent per tal de donar proves existencials per certs problemes en diferents camps de les matemàtiques on altres mètodes no ho han aconseguit.
Un dels seus principals objectius és l'estudi del comportament de les variables aleatòries. El cas en que aquestes variables compten el nombre d'esdeveniments dolents que tenen lloc en una estructura combinatòria és de particular interès. La idea del Paradigma de Poisson és estimar la probabilitat que tots aquests esdeveniments dolents no succeeixin a la vegada, quan les dependències entre ells són febles o escasses. En tal cas, aquesta probabilitat s'hauria de comportar de forma similar al cas on tots els esdeveniments són independents. El Lema Local de Lovász o la Desigualtat de Suen són exemples d'aquesta idea.
L'objectiu de la tesi és estudiar aquestes tècniques ja sigui proveint-ne noves versions, refinant-ne les existents per casos particulars o donant-ne noves aplicacions. A continuació s'enumeren les principals contribucions de la tesi.
La primera part d'aquesta tesi estén un resultat d' Erdős i Spencer sobre transversals llatins. Els autors proven que qualsevol matriu d'enters on cap nombre apareix massa vegades, admet un transversal on tots els nombres són diferents. Això equival a estudiar els aparellaments multicolors en aresta-coloracions de grafs complets bipartits. Sota les mateixes hipòtesis que, es donen resultats sobre el nombre d'aquests aparellaments. Les tècniques que s'utilitzen estan basades en l'estratègia desenvolupada per Lu i Székely.
En la segona part d'aquesta tesi s'estudien els codis identificadors. Un codi identificador és un conjunt de vèrtexs tal que tots els vèrtexs del graf tenen un veïnatge diferent en el codi. Aquí s'estableixen cotes en la mida d'un codi identificador mínim en funció dels graus i es resol parcialment una conjectura de Foucaud et al.. En un altre capítol, es mostra que qualsevol graf suficientment dens conté un subgraf que admet un codi identificador òptim.
En alguns casos, provar l'existència d'un cert objecte és trivial. Tot i així, es poden utilitzar les mateixes tècniques per obtenir resultats d'enumeració. L'estudi de patrons en permutacions n'és un bon exemple. A la tercera part de la tesi es desenvolupa una nova tècnica per tal d'estimar el nombre de permutacions d'una certa llargada que eviten còpies consecutives d'un patró donat.
En particular, es donen cotes inferiors i superiors per a aquest nombre. Una de les conseqüències és la prova de la conjectura CMP enunciada per Elizalde i Noy així com nous resultats en el comportament de la majoria dels patrons.
En l'última part de la tesi s'estudia la Conjectura Lonely Runner, enunciada independentment per Wills i Cusick i que té múltiples aplicacions en diferents camps de les matemàtiques. Aquesta coneguda conjectura diu que per qualsevol conjunt de corredors que corren al llarg d'un cercle unitari, hi ha un moment on tots els corredors estan suficientment lluny de l'origen. Aquí, es millora un resultat de Chen ampliant la distància de tots els corredors a l'origen. També s'estén el teorema del corredor invisible de Czerwiński i Grytczuk .In this thesis we study different problems in combinatorics and in graph theory by means of the probabilistic method. This method, introduced by Erdös, has become an extremely powerful tool to provide existential proofs for certain problems in different mathematical branches where other methods had failed utterly. One of its main concerns is to study the behavior of random variables. In particular, one common situation arises when these random variables count the number of bad events that occur in a combinatorial structure. The idea of the Poisson Paradigm is to estimate the probability of these bad events not happening at the same time when the dependencies among them are weak or rare. If this is the case, this probability should behave similarly as in the case where all the events are mutually independent. This idea gets reflected in several well-known tools, such as the Lovász Local Lemma or Suen inequality. The goal of this thesis is to study these techniques by setting new versions or refining the existing ones for particular cases, as well as providing new applications of them for different problems in combinatorics and graph theory. Next, we enumerate the main contributions of this thesis. The first part of this thesis extends a result of Erdös and Spencer on latin transversals [1]. They showed that an integer matrix such that no number appears many times, admits a latin transversal. This is equivalent to study rainbow matchings of edge-colored complete bipartite graphs. Under the same hypothesis of, we provide enumerating results on such rainbow matchings. The second part of the thesis deals with identifying codes, a set of vertices such that all vertices in the graph have distinct neighborhood within the code. We provide bounds on the size of a minimal identifying code in terms of the degree parameters and partially answer a question of Foucaud et al. On a different chapter of the thesis, we show that any dense enough graph has a very large spanning subgraph that admits a small identifying code. In some cases, proving the existence of a certain object is trivial. However, the same techniques allow us to obtain enumerative results. The study of permutation patterns is a good example of that. In the third part of the thesis we devise a new approach in order to estimate how many permutations of given length avoid a consecutive copy of a given pattern. In particular, we provide upper and lower bounds for them. One of the consequences derived from our approach is a proof of the CMP conjecture, stated by Elizalde and Noy as well as some new results on the behavior of most of the patterns. In the last part of this thesis, we focus on the Lonely Runner Conjecture, posed independently by Wills and Cusick and that has multiple applications in different mathematical fields. This well-known conjecture states that for any set of runners running along the unit circle with constant different speeds and starting at the same point, there is a moment where all of them are far enough from the origin. We improve the result of Chen on the gap of loneliness by studying the time when two runners are close to the origin. We also show an invisible runner type result, extending a result of Czerwinski and Grytczuk.
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Mitjana, Margarida. "Propagació d'informació en grafs i digrafs que modelen xarxes d'interconnexió simètriques." Doctoral thesis, Universitat Politècnica de Catalunya, 1999. http://hdl.handle.net/10803/315841.
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L'objectiu d'aquesta tesi és aprofondir en l'estudi d'una certa família de dígrafs, els dígrafs de prefix-cicle, donant nous detalls sobre la seva estructura, noves maneres d'enfocar el seu estudi, i dissenyant bons esquemes de comunicació. Es completa d'aquesta forma l'estudi iniciat per altres autors i s'en refoça el seu interès com a bon model de xarxa d'interconnexió.
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Salas, Piñón Julián. "On the structure of graphs without short cycles." Doctoral thesis, Universitat Politècnica de Catalunya, 2012. http://hdl.handle.net/10803/124508.
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The objective of this thesis is to study cages, constructions and properties of such families of graphs. For this, the study of graphs without short cycles plays a fundamental role in order to develop some knowledge on their structure, so we can later deal with the problems on cages. Cages were introduced by Tutte in 1947. In 1963, Erdös and Sachs proved that (k, g) -cages exist for any given values of k and g. Since then, large amount of research in cages has been devoted to their construction.
In this work we study structural properties such as the connectivity, diameter, and degree regularity of graphs without short cycles.
In some sense, connectivity is a measure of the reliability of a network. Two graphs with the same edge-connectivity, may be considered to have different reliabilities, as a more refined index than the edge-connectivity, edge-superconnectivity is proposed together with some other parameters called restricted connectivities.
By relaxing the conditions that are imposed for the graphs to be cages, we can achieve more refined connectivity properties on these families and also we have an approach to structural properties of the family of graphs with more restrictions (i.e., the cages).
Our aim, by studying such structural properties of cages is to get a deeper insight into their structure so we can attack the problem of their construction.
By way of example, we studied a condition on the diameter in relation to the girth pair of a graph, and as a corollary we obtained a result guaranteeing restricted connectivity of a special family of graphs arising from geometry, such as polarity graphs.
Also, we obtained a result proving the edge superconnectivity of semiregular cages. Based on these studies it was possible to develop the study of cages.
Therefore obtaining a relevant result with respect to the connectivity of cages, that is, cages are k/2-connected. And also arising from the previous work on girth pairs we obtained constructions for girth pair cages that proves a bound conjectured by Harary and Kovács, relating the order of girth pair cages with the one for cages. Concerning the degree and the diameter, there is the concept of a Moore graph, it was introduced by Hoffman and Singleton after Edward F. Moore, who posed the question of describing and classifying these graphs.
As well as having the maximum possible number of vertices for a given combination of degree and diameter, Moore graphs have the minimum possible number of vertices for a regular graph with given degree and girth. That is, any Moore graph is a cage. The formula for the number of vertices in a Moore graph can be generalized to allow a definition of Moore graphs with even girth (bipartite Moore graphs) as well as odd girth, and again these graphs are cages. Thus, Moore graphs give a lower bound for the order of cages, but they are known to exist only for very specific values of k, therefore it is interesting to study how far a cage is from this bound, this value is called the excess of a cage.
We studied the excess of graphs and give a contribution, in the sense of the work of Biggs and Ito, relating the bipartition of girth 6 cages with their orders. Entire families of cages can be obtained from finite geometries, for example, the graphs of incidence of projective planes of order q a prime power, are (q+1, 6)-cages. Also by using other incidence structures such as the generalized quadrangles or generalized hexagons, it can be obtained families of cages of girths 8 and 12.
In this thesis, we present a construction of an entire family of girth 7 cages that arises from some combinatorial properties of the incidence graphs of generalized quadrangles of order (q,q).
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Castellanos, Carrazana Abel. "Performance model for hybrid MPI+OpenMP master/worker applications." Doctoral thesis, Universitat Autònoma de Barcelona, 2014. http://hdl.handle.net/10803/283403.
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En el entorno actual, diversas ramas de las ciencias, tienen la necesidad de auxiliarse de la computación de altas prestaciones para la
obtención de resultados a relativamente corto plazo. Ello es debido fundamentalmente, al alto volumen de información que necesita ser
procesada y también al costo computacional que demandan dichos cálculos. El beneficio al realizar este procesamiento de manera distribuida y
paralela, logra acortar de manera notable los tiempos de espera en la obtención de los resultados.
Para soportar ello, existen fundamentalmente dos modelos de programación ampliamente extendidos: el modelo de paso de mensajes a través de
librerías basadas en el estándar MPI, y el de memoria compartida con la utilización de OpenMP. Las aplicaciones híbridas son aquellas que
combinan ambos modelos con el fin de aprovechar en cada caso, las potencialidades específicas del paralelismo en cada uno. Lamentablemente,
la práctica ha demostrado que la utilización de esta combinación de modelos, no garantiza necesariamente una mejoría en el comportamiento de
las aplicaciones. Existen varios parámetros que deben ser considerados a determinar la configuración de la aplicación que proporciona el mejor
tiempo de ejecución. El número de proceso que se debe utilizar, el número de hilos en cada nodo, la distribución de datos entre procesos e hilos,
y así sucesivamente, son parámetros que afectan seriamente elrendimiento de
la aplicación. El valor apropiado de tales parámetros depende, por una parte, de las características de arquitectura del sistema
(latencia de las comunicaciones, el ancho de banda de comunicación, el tamaño y la distribución de los niveles de memoria cache,
la capacidad de cómputo, etc.) y, por otro lado, de la características propias del comportamiento de la aplicación.
La contribución fundamental de esta tesis radica en la utilización de una técnica novedosa para la predicción del rendimiento y la
eficiencia de aplicaciones híbridas de tipo Master/Worker. En particular, dentro del mundo del aprendizaje automatizado, este método de
predicción es conocido como arboles de regresión basados en modelos análiticos. Los resultados experimentales obtenidos permiten ser
optimista en cuanto al uso de este algoritmo para la predicción de ambas métricas o para la selección de la mejor configuración de
parámetros de ejecución de la aplicación.In the current environment, various branches of science are in need of auxiliary high-performance computing to obtain relatively short-term results. This is mainly due to the high volume of information that needs to be processed and the computational cost demanded by these calculations. The benefit to performing this processing using distributed and parallel programming mechanisms is that it achieves shorter waiting times in obtaining the results. To support this, there are basically two widespread programming models: the model of message passing based on the standard libraries MPI and the shared memory model with the use of OpenMP. Hybrid applications are those that combine both models in order to take the specific potential of parallelism of each one in each case. Unfortunately, experience has shown that using this combination of models does not necessarily guarantee an improvement in the behavior of applications. There are several parameters that must be considered to determine the configuration of the application that provides the best execution time. The number of process that must be used,the number of threads on each node, the data distribution among processes and threads, and so on, are parameters that seriously affect the performance of the application. On the one hand, the appropriate value of such parameters depends on the architectural features of the system (communication latency, communication bandwidth, cache memory size and architecture, computing capabilities, etc.), and, on the other hand, on the features of the application. The main contribution of this thesis is a novel technique for predicting the performance and efficiency of parallel hybrid Master/Worker applications. This technique is known as model-based regression trees into the field of machine learning. The experimental results obtained allow us to be optimistic about the use of this algorithm for predicting both metrics and to select the best application execution parameters.
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De, la Cruz Raúl. "Leveraging performance of 3D finite difference schemes in large scientific computing simulations." Doctoral thesis, Universitat Politècnica de Catalunya, 2015. http://hdl.handle.net/10803/325139.
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Gone are the days when engineers and scientists conducted most of their experiments empirically. During these decades, actual tests were carried out in order to assess the robustness and reliability of forthcoming product designs and prove theoretical models. With the advent of the computational era, scientific computing has definetely become a feasible solution compared with empirical methods, in terms of effort, cost and reliability. Large and massively parallel computational resources have reduced the simulation execution times and have improved their numerical results due to the refinement of the sampled domain. Several numerical methods coexist for solving the Partial Differential Equations (PDEs). Methods such as the Finite Element (FE) and the Finite Volume (FV) are specially well suited for dealing with problems where unstructured meshes are frequent. Unfortunately, this flexibility is not bestowed for free. These schemes entail higher memory latencies due to the handling of irregular data accesses. Conversely, the Finite Difference (FD) scheme has shown to be an efficient solution for problems where the structured meshes suit the domain requirements. Many scientific areas use this scheme due to its higher performance.
This thesis focuses on improving FD schemes to leverage the performance of large scientific computing simulations. Different techniques are proposed such as the Semi-stencil, a novel algorithm that increases the FLOP/Byte ratio for medium- and high-order stencils operators by reducing the accesses and endorsing data reuse. The algorithm is orthogonal and can be combined with techniques such as spatial- or time-blocking, adding further improvement. New trends on Symmetric Multi-Processing (SMP) systems -where tens of cores are replicated on the same die- pose new challenges due to the exacerbation of the memory wall problem. In order to alleviate this issue, our research is focused on different strategies to reduce pressure on the cache hierarchy, particularly when different threads are sharing resources due to Simultaneous Multi-Threading (SMT). Several domain decomposition schedulers for work-load balance are introduced ensuring quasi-optimal results without jeopardizing the overall performance. We combine these schedulers with spatial-blocking and auto-tuning techniques, exploring the parametric space and reducing misses in last level cache.
As alternative to brute-force methods used in auto-tuning, where a huge parametric space must be traversed to find a suboptimal candidate, performance models are a feasible solution. Performance models can predict the performance on different architectures, selecting suboptimal parameters almost instantly. In this thesis, we devise a flexible and extensible performance model for stencils. The proposed model is capable of supporting multi- and many-core architectures including complex features such as hardware prefetchers, SMT context and algorithmic optimizations. Our model can be used not only to forecast execution time, but also to make decisions about the best algorithmic parameters. Moreover, it can be included in run-time optimizers to decide the best SMT configuration based on the execution environment.
Some industries rely heavily on FD-based techniques for their codes. Nevertheless, many cumbersome aspects arising in industry are still scarcely considered in academia research. In this regard, we have collaborated in the implementation of a FD framework which covers the most important features that an HPC industrial application must include. Some of the node-level optimization techniques devised in this thesis have been included into the framework in order to contribute in the overall application performance. We show results for a couple of strategic applications in industry: an atmospheric transport model that simulates the dispersal of volcanic ash and a seismic imaging model used in Oil & Gas industry to identify hydrocarbon-rich reservoirs.Atrás quedaron los días en los que ingenieros y científicos realizaban sus experimentos empíricamente. Durante esas décadas, se llevaban a cabo ensayos reales para verificar la robustez y fiabilidad de productos venideros y probar modelos teóricos. Con la llegada de la era computacional, la computación científica se ha convertido en una solución factible comparada con métodos empíricos, en términos de esfuerzo, coste y fiabilidad. Los supercomputadores han reducido el tiempo de las simulaciones y han mejorado los resultados numéricos gracias al refinamiento del dominio. Diversos métodos numéricos coexisten para resolver las Ecuaciones Diferenciales Parciales (EDPs). Métodos como Elementos Finitos (EF) y Volúmenes Finitos (VF) están bien adaptados para tratar problemas donde las mallas no estructuradas son frecuentes. Desafortunadamente, esta flexibilidad no se confiere de forma gratuita. Estos esquemas conllevan latencias más altas debido al acceso irregular de datos. En cambio, el esquema de Diferencias Finitas (DF) ha demostrado ser una solución eficiente cuando las mallas estructuradas se adaptan a los requerimientos. Esta tesis se enfoca en mejorar los esquemas DF para impulsar el rendimiento de las simulaciones en la computación científica. Se proponen diferentes técnicas, como el Semi-stencil, un nuevo algoritmo que incrementa el ratio de FLOP/Byte para operadores de stencil de orden medio y alto reduciendo los accesos y promoviendo el reuso de datos. El algoritmo es ortogonal y puede ser combinado con técnicas como spatial- o time-blocking, añadiendo mejoras adicionales. Las nuevas tendencias hacia sistemas con procesadores multi-simétricos (SMP) -donde decenas de cores son replicados en el mismo procesador- plantean nuevos retos debido a la exacerbación del problema del ancho de memoria. Para paliar este problema, nuestra investigación se centra en estrategias para reducir la presión en la jerarquía de cache, particularmente cuando diversos threads comparten recursos debido a Simultaneous Multi-Threading (SMT). Introducimos diversos planificadores de descomposición de dominios para balancear la carga asegurando resultados casi óptimos sin poner en riesgo el rendimiento global. Combinamos estos planificadores con técnicas de spatial-blocking y auto-tuning, explorando el espacio paramétrico y reduciendo los fallos en la cache de último nivel. Como alternativa a los métodos de fuerza bruta usados en auto-tuning donde un espacio paramétrico se debe recorrer para encontrar un candidato, los modelos de rendimiento son una solución factible. Los modelos de rendimiento pueden predecir el rendimiento en diferentes arquitecturas, seleccionando parámetros suboptimos casi de forma instantánea. En esta tesis, ideamos un modelo de rendimiento para stencils flexible y extensible. El modelo es capaz de soportar arquitecturas multi-core incluyendo características complejas como prefetchers, SMT y optimizaciones algorítmicas. Nuestro modelo puede ser usado no solo para predecir los tiempos de ejecución, sino también para tomar decisiones de los mejores parámetros algorítmicos. Además, puede ser incluido en optimizadores run-time para decidir la mejor configuración SMT. Algunas industrias confían en técnicas DF para sus códigos. Sin embargo, no todos los aspectos que aparecen en la industria han sido sometidos a investigación. En este aspecto, hemos diseñado e implementado desde cero una infraestructura DF que cubre las características más importantes que una aplicación industrial debe incluir. Algunas de las técnicas de optimización propuestas en esta tesis han sido incluidas para contribuir en el rendimiento global a nivel industrial. Mostramos resultados de un par de aplicaciones estratégicas para la industria: un modelo de transporte atmosférico que simula la dispersión de ceniza volcánica y un modelo de imagen sísmica usado en la industria del petroleo y gas para identificar reservas ricas en hidrocarburos
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Sales, i. Inglès Vicenç. "Aportaciones al estudio de los sistemas electorales." Doctoral thesis, Universitat Politècnica de Catalunya, 2016. http://hdl.handle.net/10803/385426.
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An important question that modern societies have to decide is the election of some people who represent them and can also make some decisions. Mechanisms to do it are called Electoral Systems. In fact, there are a lot of them and they are very different. In this work, we present some ideas to carry out a mathematical analysis of them.
The first chapter is a global analysis of electoral systems. It begins with the definition of electoral system --helped by Probability Theory-- and the introduction of most important simple examples found in practice. Next we define two operations on electoral systems and, in particular, we obtain two different generalizations of each one of the examples. We also introduce some important properties that electoral systems may have -- superadditivity, monotonicity, increasing and stability-- and we study which examples enjoy them and the behavior of these properties with respect to the operations defined before. Finally, stability give us the possibility to define majority and proportional electoral systems.
In the second chapter we study electoral systems individually. In this sense, we introduce the electoral expectatives, obtained when the vote vector of an arbitrary list of candidates is fixed. Then we study their connection with the operations before defined and we finish the chapter by introducing some individual properties that electoral systems may have and analysing what happens when we consider again the operations defined before.
The third chapter refers to a parameter introduced to assess whether an arbitrary list of candidates gets profit or not from an electoral system. The way used to do it consists in considering the expected value of electoral expectatives introduced in the second chapter. We obtain in this form the concept of average electoral expectative. And we finish the chapter by studying the behavior of this concept with respect to the operations and examples introduced above.
In the fourth chapter we analyse three questions of majority weighted games that we will use in the next chapter: another form to define them, a new operation between them and their convergence.
Finally, in the fifth chapter we replace the number of seats of each litst of candidates by its Shapley-Shubik power index and we study the electoral systems using this new indicator. In this form, we obtain the concept of power system and, analogously, the concepts of power expectative and average power expectative. We finish by introducing some new properties of each one of these concepts and we also analyse their relation with the analogous properties of electoral systems.Una cuestión importante que las sociedades modernas deben decidir es la elección de algunos individuos que los representen y puedan asimismo tomar ciertas decisiones. Los mecanismos encargados de hacer esto se llaman Sistemas Electorales. De hecho, existen muchos y son muy diferentes. En este trabajo, presentamos algunas ideas para analizamos matemáticamente. El primer capítulo es un análisis global de los sistemas electorales. Comienza con la definición de sistema electoral --con la ayuda de la Teoría de Probabilidades-- y la introducción de los ejemplos simples más importantes que hay. Después definimos dos operaciones para los sistemas electorales, con lo que obtenemos dos generalizaciones diferentes de cada uno de los ejemplos. Introducimos también algunas propiedades importantes que pueden poseer los sistemas electorales --superaditividad, monotonía, crecimiento y estabilidad-- y estudiamos cuáles de los ejemplos las poseen y el comportamiento de dichas propiedades respecto de las operaciones anteriormente definidas. Finalmente, la estabilidad nos proporciona la posibilidad de definir los sistemas electorales mayoritarios y proporcionales. En el segundo capítulo estudiamos los sistemas electorales desde el punto de vista individual. En tal sentido, introducimos las expectativas electorales, obtenidas fijando el vector de votos de una candidatura arbitraria. Seguidamente, estudiamos su relación con las operaciones anteriormente definidas y terminamos el capítulo introduciendo algunas propiedades de tipo individual que los sistemas electorales pueden poseer y analizando qué sucede cuando consideramos las operaciones anteriores. El tercer capítulo trata sobre un parámetro introducido para evaluar si una candidatura cualquiera resulta beneficiada o no por un sistema electoral. La forma de hacerlo ha sido considerar la media de las expectativas electorales introducidas en el segundo capítulo. Obtenemos de esta forma el concepto de expectativa electoral media. Y finalizamos el capítulo estudiando de nuevo su comportamiento respecto de las operaciones y los ejemplos introducidos. En el cuarto capítulo analizamos tres cuestiones sobre juegos de mayoría ponderada que serán utilizados en el capítulo siguiente: otra forma de definirlos, una nueva operación entre ellos y su convergencia. Finalmente, en el quinto capítulo substituimos el número de respresentantes de cada candidatura por su índice de poder de Shapley-Shubik y estudiamos los sistemas electorales utilizando este nuevo indicador. De esta forma, obtenemos el concepto de sistema de poder y, análogamente, los de expectativa de poder y expectativa de poder media. E introducimos algunas propiedades nuevas sobre cada uno de los conceptos anteriores y analizamos también su relación con las propiedades análogas de los sistemas electorales.
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Font, Valverde Martí. "Bayesian analysis of textual data." Doctoral thesis, Universitat Politècnica de Catalunya, 2016. http://hdl.handle.net/10803/384329.
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En esta tesis se desarrolla, siempre con el enfoque bayesiano en mente, una metodología estadística para el análisis de datos discretos en su aplicación en problemas estilometría. El análisis estadístico del estilo literario se ha utilizado para caracterizar el estilo de textos y autores, y para ayudar a resolver problemas de atribución de autoría. Estudios anteriores caracterizaron el estilo usando la longitud de las palabras, la longitud de las oraciones, y la proporción de los sustantivos, artículos, adjetivos o adverbios. Los datos que aquí se utilizan van, desde la frecuencia de frecuencias de palabras, hasta el análisis simultáneo de la frecuencia de longitud de palabra y de las palabras funcionales más frecuentes. Todos estos datos son característicos del estilo de autor y al mismo tiempo independiente del contexto en el que escribe. De esta forma, se introduce un análisis bayesiano de la frecuencia de frecuencias de palabras, que tiene una distribución en forma de J inversa con las colas superiores extraordinariamente largas. Se basa en la extensión de la metodología no bayesiana de Sichel para estos datos utilizando el modelo Poisson inversa gaussiana. Los modelos se comprueban mediante la exploración de la distribución a posteriori de los errores de Pearson y por la implementación de controles de consistencia de la distribución predictiva a posteriori. La distribución a posteriori de la inversa gausiana tiene una interpretación útil, al poder ser vista como una estimación de la distribución vocabulario del autor, de la cual se pueden obtener la riqueza y diversidad de la escritura del autor. Se propone también un análisis alternativo basado en la mixtura inversa gaussiana - poisson truncada en el cero, que se obtiene cambiando el orden de la mezcla y el truncamiento. También se propone un análisis de la heterogeneidad de estilo, que es un compromiso entre el modelo de punto de cambio, que busca un cambio repentino de estilo, y el análisi de conglomerados, que no tiene en cuenta el orden. El análisis incorpora el hecho de que partes próximas de un texto tienen más probabilidades de pertenecer al mismo autor que partes del texto más separadas. El enfoque se ilustra volviendo a revisar la atribución de autoría del Tirant lo Blanc. Para el análisis de la heterogeneidad del estilo literario se propone también un análisis estadístico que utiliza simultáneamente diferentes características estilométricas, como la longitud palabra y la frecuencia de las palabras funcionales más frecuentes. Las filas de todas tablas de contingencia se agrupan simultáneamente basandose en una mezcla finita de conjuntos de modelos multinomiales con un estilo homogéneo. Esto tiene algunas ventajas sobre las heurísticas utilizadas en el análisis de conglomerados, ya que incorpora naturalmente el tamaño del texto, la naturaleza discreta de los datos y la dependencia entre las categorías. Todo ello se ilustra a través del análisis del estilo en las obras de teatro de Shakespeare, el Quijote y el Tirant lo Blanc. Finalmente, los problemas de atribución y verificación de autoría, que se tratan normalmente por separado, son tratados de forma conjunta. Esto se hace asumiendo un escenario abierto de clasificación para el problema de la atribución, contemplando la posibilidad de que ninguno de los autores candidatos, con textos conocidos para aprendijaje, es el autor de los textos en disputa. Entonces, el problema de verificación se convierte en un caso especial de problema de atribución. El modelo multinomial bayesiano propuesto permite obtener una solución exacta y cerrada para este problema de atribución de autoría más general. El enfoque al problema de verificación se ilustra mediante la exploración de si un fallo judicial condenatorio podría haber sido escrito por el juez que lo firma o no, y el enfoque al problema de atribución se ilustra revisando el problema de la autoría de los Federalist Papers.In this thesis I develop statistical methodology for analyzing discrete data to be applied to stylometry problems, always with the Bayesian approach in mind. The statistical analysis of literary style has long been used to characterize the style of texts and authors, and to help settle authorship attribution problems. Early work in the literature used word length, sentence length, and proportion of nouns, articles, adjectives or adverbs to characterize literary style. I use count data that goes from the frequency of word frequency, to the simultaneous analysis of word length counts and more frequent function words counts. All of them are characteristic features of the style of author and at the same time rather independent of the context in which he writes. Here we intrude a Bayesian Analysis of word frequency counts, that have a reverse J-shaped distribution with extraordinarily long upper tails. It is based on extending Sichel's non-Bayesian methodology for frequency count data using the inverse gaussian Poisson model. The model is checked by exploring the posterior distribution of the Pearson errors and by implementing posterior predictive consistency checks. The posterior distribution of the inverse gaussian mixing density also provides a useful interpretation, because it can be seen as an estimate of the vocabulary distribution of the author, from which measures of richness and of diversity of the author's writing can be obtained. An alternative analysis is proposed based on the inverse gaussian-zero truncated Poisson mixture model, which is obtained by switching the order of the mixing and the truncation stages. An analysis of the heterogeneity of the style of a text is proposed that strikes a compromise between change-point, that analyze sudden changes in style, and cluster analysis, that does not take order into consideration. Here an analysis is proposed that strikes a compromise by incorporating the fact that parts of the text that are close together are more likely to belong to the same author than parts of the text far apart. The approach is illustrated by revisiting the authorship attribution of Tirant lo Blanc. A statistical analysis of the heterogeneity of literary style in a set of texts that simultaneously uses different stylometric characteristics, like word length and the frequency of function words, is proposed. It clusters the rows of all contingency tables simultaneously into groups with homogeneous style based on a finite mixture of sets of multinomial models. That has some advantages over the usual heuristic cluster analysis approaches as it naturally incorporates the text size, the discrete nature of the data, and the dependence between categories. All is illustrated with the analysis of the style in plays by Shakespeare, El Quijote, and Tirant lo Blanc. Finally, authorship attribution and verification problems that are usually treated separately are treated jointly. That is done by assuming an open-set classification framework for attribution problems, contemplating the possibility that neither one of the candidate authors, with training texts known to have been written by them is the author of the disputed texts. Then the verification problem becomes a special case of attribution problems.A formal Bayesian multinomial model for this more general authorship attribution is given and a closed form solution for it is derived. The approach to the verification problem is illustrated by exploring whether a court ruling sentence could have been written by the judge that signs it or not, and the approach to the attribution problem illustrated by exploring whether a court ruling sentence could have been written by the judge that signs it or not, and the approach to the attribution problem is illustrated by revisiting the authority attribution
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Argollo, de Oliveira Dias Júnior Eduardo. "Performance prediction and tuning in a multi-cluster environment." Doctoral thesis, Universitat Autònoma de Barcelona, 2006. http://hdl.handle.net/10803/5761.
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Los clusters de computadores son una alternativa actual usada para el cómputo de aplicaciones científicas. Sin embargo las aplicaciones crecen en complejidad y necesitan más recursos. Unir estos clusters distribuidos usando Internet en un multi-cluster puede permitir lograrlo. Un problema que se introduce con esta colaboración es un incremento en la heterogeneidad tanto de cómputo como de comunicación, aumentando la complejidad de dicho sistema lo que dificulta su uso.
El objetivo de esta tesis es lograr la reducción del tiempo de ejecución de aplicaciones, originalmente desarrolladas para un cluster, usando eficientemente un multi-cluster.
Proponemos una arquitectura del sistema para lograr una máquina virtual multi-cluster transparente a la aplicación que además la dota de escalabilidad y robustez tolerando los problemas de la comunicación por Internet. Esta arquitectura propone un master-worker jerárquico en el que se introducen elementos claves como los gestores de comunicación que dotan al sistema de robustez, seguridad y transparencia en las comunicaciones entre clusters a través de Internet.
Desarrollamos un modelo de prestaciones para poder hacer una estimación teórica del tiempo de ejecución y de la eficiencia de una aplicación ejecutándose en un multi-cluster. La precisión de las estimaciones es superior al 90%.
Proponemos una metodología que da un procedimiento que define los pasos para realizar la predicción del tiempo de ejecución, para garantizar un umbral de eficiencia seleccionando los recursos adecuados y para guiar a la sintonización de la aplicación encontrando los cuellos de botella de la ejecución.
Clusters of computers represent an alternative for speeding up scientific applications. Nevertheless applications grow in complexity and need more resources. The joint of distributed clusters, using Internet, in a multi-cluster can allow the resources obtainment.
A problem on reaching an effective collaboration from multiple clusters is the increase on the computation and communication heterogeneity. This factor increases the complexity of such a system bringing difficulties in its use.
The target of this thesis is to attain the reduction of the execution time of applications, originally written for a single cluster, efficiently using a multi-cluster. In order to reach this goal we propose a system architecture, an analytical model and a performance and tuning methodology.
The proposed system architecture aims to obtain a multi-cluster virtual machine, transparent to the application and that provides scalability and robustness, tolerating possible faults in the Internet communication between clusters. This architecture is organized around a hierarchical master-worker with communication managers. Communication managers are a key element responsible for the robustness, security and transparency in the communication between clusters using Internet.
The analytical performance model was developed to estimate the execution time and efficiency of an application executing in a multi-cluster. The precision on the estimations are over 90%.
The proposed performance prediction and application tuning methodology is a procedure that defines the steps to predict the execution time and efficiency, to guarantee an efficiency threshold and to guide on the application tuning, evaluating the execution bottlenecks.
Books on the topic "[519.1"
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United States. Congress. House. Committee on Small Business. Small Business Equity Enhancement Act of 1992: Report (to accompany H.R. 5191). [Washington, D.C.?: U.S. G.P.O., 1992.
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United States. Congress. House. Committee on Rules. Providing for the consideration of H.R. 5191: Report (to accompany H. Res. 531). [Washington, D.C.?: U.S. G.P.O., 1992.
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United States. Congress. House. Committee on Rules. Providing for the consideration of H.R. 5191: Report (to accompany H. Res. 531). [Washington, D.C.?: U.S. G.P.O., 1992.
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Ross, Sheldon M. Stochastic processes. 2nd ed. New York: Wiley, 1996.
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Marylees, Miller, and Freund John E, eds. John E. Freund's mathematical statistics with applications. 8th ed. Upper Saddle River, N.J: Pearson Education, 2013.
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Marylees, Miller, and Freund John E. 1921-, eds. John E. Freund's mathematical statistics. 6th ed. London: Prentice-Hall International, 1999.
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Marylees, Miller, and Freund John E, eds. John E. Freund's mathematical statistics. 6th ed. Upper Saddle River, N.J: Prentice Hall, 1999.
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1931-, Mayers D. F., ed. An introduction to numerical analysis. Cambridge: Cambridge University Press, 2006.
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R, Reeves Colin, ed. Modern heuristic techniques for combinatorial problems. London: McGraw-Hill, 1995.
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1953-, Smith Richard L., ed. Essentials of statistical inference: G.A. Young, R.L. Smith. Cambridge, UK: Cambridge University Press, 2010.
Find full textBook chapters on the topic "[519.1"
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Quattrocchi, Umberto. "L." In CRC World Dictionary of Plant Names, 1399–557. Boca Raton: CRC Press, 2023. http://dx.doi.org/10.1201/b22802-5191.
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Ageev, Petr, and Svetlana Tarashnina. "Competition as a Hierarchical Multistage Game." In Static & Dynamic Game Theory: Foundations & Applications, 1–11. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-51941-4_1.
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Kuzyutin, Denis, Ivan Lipko, Yaroslavna Pankratova, and Igor Tantlevskij. "Cooperation Enforcing in Multistage Multicriteria Game: New Algorithm and Its Implementation." In Static & Dynamic Game Theory: Foundations & Applications, 141–59. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-51941-4_10.
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Meza, Mario Alberto Garcia, and Cesar Gurrola Rios. "Complementarity of Goods and Cooperation Among Firms in a Dynamic Duopoly." In Static & Dynamic Game Theory: Foundations & Applications, 161–71. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-51941-4_11.
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Orlova, Ekaterina. "Cooperative Solutions for the Eurasian Gas Network." In Static & Dynamic Game Theory: Foundations & Applications, 173–200. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-51941-4_12.
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Rokhlin, Dmitry B., and Gennady A. Ougolnitsky. "Optimal Incentive Strategy in a Continuous Time Inverse Stackelberg Game." In Static & Dynamic Game Theory: Foundations & Applications, 201–13. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-51941-4_13.
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Petrosian, Ovanes, Maria Nastych, and Yin Li. "The Looking Forward Approach in a Differential Game Model of the Oil Market with Non-transferable Utility." In Static & Dynamic Game Theory: Foundations & Applications, 215–44. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-51941-4_14.
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Rothfuß, Simon, Jannik Steinkamp, Michael Flad, and Sören Hohmann. "Cooperative Decision Making in Cooperative Control Systems by Means of Game Theory." In Static & Dynamic Game Theory: Foundations & Applications, 245–65. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-51941-4_15.
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Sidorov, Alexander. "Social Inefficiency of Free Entry Under the Product Diversity." In Static & Dynamic Game Theory: Foundations & Applications, 267–81. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-51941-4_16.
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Shevchenko, Igor. "An Alternative Pursuit Strategy in the Game of Obstacle Tag." In Static & Dynamic Game Theory: Foundations & Applications, 283–94. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-51941-4_17.
Full textConference papers on the topic "[519.1"
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Lambert, Arthur W., Sait Ozturk, and Sam Thiagalingam. "Abstract 5191: Periostin signaling in breast cancer stem cells." In Proceedings: AACR 103rd Annual Meeting 2012‐‐ Mar 31‐Apr 4, 2012; Chicago, IL. American Association for Cancer Research, 2012. http://dx.doi.org/10.1158/1538-7445.am2012-5191.
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Khalil, Md Imtiaz, Shu Yang, Anthony Blankenship, Zachary Connelly, and Xiuping Yu. "Abstract 5191: Functional role of EZH2 in neuroendocrine prostate cancer." In Proceedings: AACR Annual Meeting 2019; March 29-April 3, 2019; Atlanta, GA. American Association for Cancer Research, 2019. http://dx.doi.org/10.1158/1538-7445.sabcs18-5191.
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Khalil, Md Imtiaz, Shu Yang, Anthony Blankenship, Zachary Connelly, and Xiuping Yu. "Abstract 5191: Functional role of EZH2 in neuroendocrine prostate cancer." In Proceedings: AACR Annual Meeting 2019; March 29-April 3, 2019; Atlanta, GA. American Association for Cancer Research, 2019. http://dx.doi.org/10.1158/1538-7445.am2019-5191.
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Frees, Sebastian K., Igor Moskalev, Betty Zhou, Peter Raven, Claudia Chavez-Munoz, Peter Black, and Alan I. So. "Abstract 5191: An orthotopic xenograft renal cell carcinoma Sunitinib resistant murine model." In Proceedings: AACR 107th Annual Meeting 2016; April 16-20, 2016; New Orleans, LA. American Association for Cancer Research, 2016. http://dx.doi.org/10.1158/1538-7445.am2016-5191.
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McCleland, Mark, Adam Adler, and Ron Firestein. "Abstract 5191: Dual roles for CDK8 in cancer and stem cell maintenance." In Proceedings: AACR 102nd Annual Meeting 2011‐‐ Apr 2‐6, 2011; Orlando, FL. American Association for Cancer Research, 2011. http://dx.doi.org/10.1158/1538-7445.am2011-5191.
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Zhang, Xiaocui, Geneviève Lavoie, Loic Fort, Edward L. Huttlin, Joseph Tcherkezian, Jacob A. Galan, Haihua Gu, Steven P. Gygi, Sebastien Carreno, and Philippe P. Roux. "Abstract 5191: Gab2 phosphorylation by RSK inhibits Shp2 recruitment and cell motility." In Proceedings: AACR 104th Annual Meeting 2013; Apr 6-10, 2013; Washington, DC. American Association for Cancer Research, 2013. http://dx.doi.org/10.1158/1538-7445.am2013-5191.
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Agostinho Hernandez, Bruno, Alexander Paterno, Edson Antonio Capello Sousa, João Paulo de Oliveira Freitas, and Cesar Renato Foschini. "Fatigue Analysis of Dental Prostheses by Finite Element Method (FEM)." In ASME 2015 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/imece2015-51911.
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Introduction and Objectives: The dental prostheses are typical biomechanical structures because they have the objective to restore the mastication functions and are responsible for replacing the original tooth that was damaged. In the last few years, many studies have been done and big achievements have been noticed in this area. However, clinical studies and experimental procedures for these conditions are sometimes impractical, due to the biological nature of these components and the difficult to reproduce and to analyze such conditions. Moreover, it involves complex geometries, loads and mechanical behaviors, which analytical solution is very difficult to achieve. For these reasons, many researchers have applied the Finite Element Method (FEM). This method allows the evaluation of non-linear situations (e.g. biomechanical interactions) with complex geometries where experimental tests are usually difficult to be conducted. Furthermore, the uses of this method allow failure evaluation and it forecast occurrence. Like any mechanical structure, prostheses are sensible to failures. The cyclic nature of the loading that components are exposed means that fatigue failures are the type of failure which needs more attention in these kinds of structures. Therefore, this project aims to develop a tridimensional finite element model of dental prosthesis in order to evaluate the fatigue problem. Methods: A geometric model from a single dental prosthesis compounded by an implant, an abutment screw, an abutment, a fixation’s screw and a crown will be generated from Micro CT and scanning data. Then, the geometry will be exported to finite element software where a finite element model will be created. After these steps, boundaries conditions will be applied and simulations will be done. Finally, the simulation results will be analyzed. Results: The results from fatigue simulations and analysis demonstrated that abutment screw will have a finite life in most of the analyzed cases, and the fixation screw will be an infinite life. Conclusion: The results obtained illustrate the efficiency of Finite Element Method on simulating the biomechanical conditions, mainly in dental prostheses. In this study, the fatigue conditions were explored and analyzed. Finally, the knowledge about this problem could be improved.
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Maghsoudi, Elham, Uday Godse, and Alistair Gill. "Multiphase CFD Analysis of a Subsea Intervention System." In ASME 2015 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/imece2015-51921.
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In this study, a computational fluid dynamics (CFD) analysis was conducted to evaluate a new design of an intervention system. A multiphase analysis was performed to understand the mixing characteristics as the cement is pumped into the well and the degree to which the cement could be contaminated with spacer fluid. A transient multiphase analysis was conducted to examine the flow and the mixing behavior through the various sections of the intervention system. A combination of 2D and 3D CFD models was used, depending upon the geometry in each section. The results indicated that the intervention system operates efficiently without diluting the cement. Non-Newtonian methods used in CFD were validated using available theoretical and experimental data. In a large-scale yard test, good agreement was obtained for resin and water; however, cement did not show good agreement as the flow rate increased over 1 bbl/min.
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Lee, S. H., H. Tchelepi, and L. F. DeChant. "Implementation of a Flux-Continuous Finite Difference Method for Stratigraphic, Hexahedron Grids." In SPE Reservoir Simulation Symposium. Society of Petroleum Engineers, 1999. http://dx.doi.org/10.2118/51901-ms.
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Edwards, Michael G., Li Bin, and Khalid Aziz. "Modular Mesh Generation With Embedded Streamline Potential Grids." In SPE Reservoir Simulation Symposium. Society of Petroleum Engineers, 1999. http://dx.doi.org/10.2118/51911-ms.
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