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1
Angelini, Lorenzo. "Valutazione della massa equivalente per i veicoli da trasporto pubblico urbano: effetti della trasmissione." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2017. http://amslaurea.unibo.it/13037/.
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L’obiettivo del presente elaborato consiste nel valutare l’incidenza del fenomeno della massa equivalente negli autobus utilizzati per il trasporto pubblico urbano sia da un punto di vista prestazionale che per quanto concerne il comfort dei passeggeri.
A tal fine si è indagata nel dettaglio la correlazione tra la massa equivalente e la tipologia di trasmissione del veicolo partendo dallo studio dell’equazione del moto e dalla differenziazione tra
caratteristica meccanica interna riferita al motore e caratteristica propulsiva ideale riferita all’organo propulsore.
Successivamente sono stati analizzati i parametri che entrano in gioco nella determinazione della massa equivalente, con particolare attenzione al rapporto totale di trasmissione e quindi sono stati trattati tutti gli organi di trasmissione del moto e in particolar modo, dipendendo il rapporto totale di trasmissione dal rapporto al cambio, sono state studiate le varie tipologie di cambi, soffermandosi principalmente su una particolare tipologia di cambio automatico, ovvero il Cambio ZF Ecomat 4
modello HP 604 C.
In seguito, partendo dai dati delle caratteristiche tecniche del motore New Cursor 8 e del sopraccitato cambio ZF, forniti dall’azienda di Trasporto Passeggeri Emilia-Romagna (Tper) e montati sugli Autosnodati Citelis da 18 metri a CNG (Compressed Natural Gas) e Diesel, si è calcolato numericamente per ogni marcia il valore del coefficiente di massa equivalente.
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Vercilli, Maria Chiara. "Studio del comportamento sismico di edifici multipiano in CLT in differenti zone sismiche e climatiche." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2017.
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A partire da quanto già scoperto grazie al progetto TimBeest, in questo elaborato si è studiato il comportamento sismico di edifici in Cross-lam Lamited Timber (CLT) a tre, cinque e sette piani in diverse zone sismiche e climatiche in Italia. Per ognuna di queste strutture si è studiato quanto e in che modo influiscono il fattore di struttura della costruzione, la presenza o meno di massa termica nei pacchetti di solai e pareti, e il tipo di analisi eseguita, sui risultati che ne rispecchiano il comportamento sismico.
Infine si è fatto un confronto tra tutti i risultati ottenuti in termini di sollecitazioni, di periodi principali di vibrazione e numero di connessioni necessarie per un buon livello di dissipazione di energia sismica da parte dell'edificio. In questo modo si è cercato di capire dove e in quali condizioni è possibile costruire questa tipologia di edifici in Italia.
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Barreto, Marco Antonio Zanussi. "Dinâmica longitudinal : efeitos da geometria de suspensão nas mudanças de atitude da massa suspensa e os esforços nos elementos da suspensão." Universidade de São Paulo, 2005. http://www.teses.usp.br/teses/disponiveis/18/18135/tde-22122005-165842/.
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Este trabalho tem como objetivo estudar a influência da geometria de suspensão do veículo nas atitudes da massa suspensa. Apresenta um confronto entre obras e autores e está segmentada em três partes; onde na primeira parte são definidos os conceitos básicos como dive, squat, lift, anti-dive, anti-squat, anti-lift e equivalente trailing-arm; na segunda parte são apresentadas as limitações e os novos conceitos definidos por R. S. Sharp e na terceira parte é apresentado o modelo dinâmico bidimensional introduzido por Fu-Cheng Wang. Apresenta um modelo virtual em sistema de multi-corpos desenvolvido no programa ADAMS, com todos os subsistemas que compõe um veículo completo. Inova ao trazer como objeto de estudo um veículo de competição (fórmula SAE) que possui como particularidade o sistema de suspensão push-rod. Surpreende com os resultados obtidos, pois, contrariam os conceitos básicos encontrados na maioria dos livrosThis work has objective study the influence of suspension geometry on the sprung mass attitudes. It presents a confrontation among works and authors and this segmented in three parts; where in the first part the basic concepts are defined, dive, squat, lift, anti-dive, anti-squat, anti-lift and equivalent trailing-arm; in the second part the limitations are presented and the new concepts are defined for R. S. Sharp and in the third part are presented the bidimensional dynamic model introduced by Fu-Cheng Wang. It presents a virtual model in system of multi-bodies developed in the program ADAMS, with all the subsystems that composes a complete vehicle. It innovates when bringing such object to study one vehicle of competition (formula SAE) that it has a particularity suspension system push-rod. It surprises with results because its opposite of the basic concepts which is present in the majority of books
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Maya, Manzano Cristina. "Práctica de la actividad física en trabajadores de universidad." Master's thesis, Universidade de Évora, 2013. http://hdl.handle.net/10174/16367.
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Objetivo: conocer los niveles de actividad física, salud y calidad de vida de dos
grupos de personal universitario, personal docente investigador (PDI) y personal
administración y servicios (PAS).
Metodología: se utilizó el cuestionario IPAQ para calcular los equivalentes
metabólicos (METs) y determinar si la actividad física (AF) es baja, moderada o alta.
Además se calculó el índice de masa corporal (IMC) para clasificar la muestra en
infrapeso, normal, sobrepeso y obesidad. Por otra parte, se dividió la muestra en dos
grupos considerando la edad (≤49 años y ≥50 años) para determinar si existe relación
por un lado entre la edad y cantidad de actividad física y por otro entre edad e IMC. Se
realizaron los análisis descriptivos y se aplicó el test de Pearson para determinar la
relación entre las variables estudiadas.
Resultados: existe una correlación significativa entre la variable género y el IMC
(r=0.505; p<0.050). El 80% de mujeres y el 36,2% de hombres tienen un IMC normal.
El 55% de mujeres y el 44,7% de hombres realizan un nivel de AF alto, el 15% de
mujeres y el 31,9% de hombres presentan un nivel de AF moderado, y por último el
30% de mujeres y el 23,4% de hombres se encuentran en el nivel de AF bajo.
Conclusiones: los resultados obtenidos reflejan que el IMC de los encuestados es
normal y que el nivel práctica de actividad física es alto en su mayoría. No hay relación
entre la edad y el IMC, ni entre edad y nivel de actividad física; ABSTRACT:Objective: to determine levels of physical activity, health and quality of life from
two university staff groups: 1) teaching and research staff (PDI); 2) administrative and
service staff (PAS).
Methodology: IPAQ questionnaire was used to calculate metabolic equivalents
(METs) and determine whether Physical Activity (PA) is low, moderate or high. We
also calculated the Body Mass Index (BMI) to classify the sample in: underweight,
normal, overweight and obesity. Moreover, the sample was divided into two groups
according to age (≤ 49 years and ≥ 50 years), to determine the existence of a
relationship between the age and the amount of physical activity on the one hand and
between age and BMI on the other hand. Descriptive analyzes were performed and
Pearson test was applied to determine the relationship between studied variables.
Results: we found a significant correlation between the gender variable and BMI
(r = 0.505, P <0.050). 80% of women and 36.2% of men have a normal BMI. 55% of
women and 44.7% of men perform a high AF level, 15% of women and 31.9% of men
have a moderate AF level, and finally, 30% of women and 23.4% of men are in the low
level of AF.
Conclusions: results show that respondents BMI is normal and that the physical activity
level is mostly high. There is no relationship between Age and BMI, nor between Age
and Physical Activity Level.
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Ceccacci, Silvia. "Equivalenza massa-energia: conseguenze a livello nucleare e subnucleare." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2012. http://amslaurea.unibo.it/4123/.
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Shiomi, Sachie. "Test mass metrology for tests of the equivalence principle." Thesis, University of Birmingham, 2002. http://etheses.bham.ac.uk//id/eprint/96/.
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The Equivalence Principle is accepted as one of the most fundamental principles in modern Physics. However, theories towards the unification of the four forces typically predict violations of this principle. Testing it at a high sensitivity is expected to make a breakthrough in the current understanding of Physics. A space-based project, STEP (Satellite Test of the Equivalence Principle), aims at testing the principle to the level of 10\(^{−18}\). This corresponds to an improvement of the current limits, established by ground-based experiments, by approximately five orders of magnitudes. To achieve the sensitivity, imperfections in STEP test masses, such as density inhomogeneity and thermal distortion, could be a problem. This thesis presents preliminary work on the verification of STEP test masses. We have measured density inhomogeneities in materials intended to be used as STEP test masses (beryllium and niobium). In addition, we have developed a device to measure differential thermal expansion of samples that cannot be machined, by using a capacitive sensing method. It is shown that the device has a precision of approximately 0.3 % in the differential thermal expansion of beryllium. This device could in principle be applied for the measurements of the real STEP test masses in the final shape. Our analysis based on the results of our measurements and literature survey shows that it is feasible to obtain materials that satisfy STEP requirements.
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Jade, (B) Sridevi. "Numerical Modeling Of Jointed Rock Mass." Thesis, Indian Institute of Science, 2000. http://hdl.handle.net/2005/257.
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The behavior of jointed rock mass is very complex and is influenced by many factors such as location of joints, joint frequency, joint orientation and joint strength. A thorough review of literature on different aspects of jointed rock mass indicate that the discontinuities or planes of weakness present in rock mass significantly influence its behavior. Numerous experimental tests were conducted to study the behavior of natural as well as artificial joints in rocks. Laboratory tests are time consuming and give results applicable to specific joint fabric and confining pressure. Numerical methods are the best alternative to laboratory tests to study the behavior of jointed rock mass. With the advent of computers numerical methods of analysis have become very popular, as they are highly flexible and can represent all complex geometries and material behavior. The accuracy of a numerical model depends upon the how well constitutive relations for the jointed rock mass are defined in the analysis. Empirical relationships for describing the mechanical behavior of discontinuities obtained from scaling the laboratory data is crucial unresolved problem, which will affect the quality of results obtained. One more important aspect in the numerical model is strength criteria used for jointed rock mass. The applicability of existing strength criteria to a particular jointed rock has to be carefully examined before they are used.
Equivalent continuum approach simplifies the modeling of jointed rock mass as the joints are not modeled separately. Instead in equivalent continuum approach the jointed rock mass is represented by an equivalent continuum whose properties are defined by a combination of intact rock properties and joint properties. The accuracy of this kind of modeling depends upon the relationships used to define the jointed rock mass properties as a function of intact rock properties and joint properties. In the present study, an effort has been made (i) to establish empirical relations to define the properties of jointed rock mass as a function of intact rock properties and joint factor (ii) to develop a numerical model based on equivalent continuum approach using the empirical relations derived above, for easy and efficient modeling of jointed rock mass (iii) comparison of existing strength criteria for jointed rock masses using the equivalent continuum model developed above (iv) Modeling of joints explicitly and comparing these results with the equivalent continuum model results.
Empirical relationships expressing the uniaxial compressive strength and elastic modulus of jointed rock as a function of corresponding intact rock properties and joint factor have been derived based on the statistical analysis of large amount of experimental data of uniaxial and triaxial tests collected from the literature. The effect of joints in the jointed rock is taken in to account by the joint factor. A comparative study of the empirical relationships arrived by the above analysis has been made to choose the best relation for the numerical analysis. Empirical relationships thus arrived for jointed rock mass are used in the equivalent continuum approach to represent the jointed rock properties as a combination of intact rock properties and joint factor. Equivalent continuum model developed is thoroughly tested, validated and applied for single, multiple and block jointed rocks. The equivalent continuum model developed has been applied for analysis of the power cavern for Shiobara power station. Different strength criteria available for jointed rock namely Mohr-Coulomb, Hoek and Drown, Yudhbir et al. and Rarnamurthy are incorporated in the equivalent continuum model to evaluate their applicability for jointed rock masses. Ramarnurthy's strength criterion gives the best values of failure stress for almost all the test cases and hence used in the equivalent continuum model.
Alternatively, the joints in jointed rock mass are represented explicitly using interface element in the nonlinear finite element analysis. The explicit finite element model has been tested and validated using the experimental stress strain curves and failure stress values. Comparison of results obtained using equivalent continuum analysis and explicit modeling of joints has been given in the form of stress strain curves and failure stress plots for jointed rock masses along with the experimental results.
Some of the major conclusions from the present study are as follows. Statistical relationships arrived to express the properties of the jointed rock as a function of intact rock and joint factor give a fair estimate of jointed rock in the absence of experimental data. Equivalent continuum model developed using statistical relations arrived above simplifies the numerical modeling of jointed rock to a large extent and also gives a fair estimate of jointed rock behavior with minimum input data. From the equivalent continuum analysis of Shiobara power cavern, it can be concluded that this approach is very advantageous for modeling highly discontinuous systems provided the joint factor is estimated properly so that it represents the real fabric of the joints present in the system. Comparison of different strength criteria shows that Ramamurthy's strength criterion is the best for jointed rocks. When the rock mass has one or two major joints it is advantageous to model it explicitly so that the behavior of the joint can be studied in detail. Explicit representation of the joints in the finite element analysis gives a lair estimate of the zones most susceptible to failure in a jointed rock. From comparison of experimental values, equivalent continuum model results and the explicit joint model results, it can be concluded that results obtained using equivalent continuum model are nearest to the experimental results in almost all the cases.
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Thigpen, Ashley Lauren Clark C. Randall. "Chromatographic and mass spectral studies on mass equivalent substituted phenethlamines related to MDEA, MDMMA and MBDB." Auburn, Ala., 2006. http://repo.lib.auburn.edu/2006%20Fall/Theses/THIGPEN_ASHLEY_11.pdf.
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Li, Bingjue. "Improving Techniques for Center of Mass Estimation Using Statically Equivalent Serial Chain Modeling." University of Dayton / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1374170027.
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Tajmar, Martin. "Weak-Equivalence Principle Violation and Mass Change of Charged Matter Due to Vacuum Polarization." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-197185.
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Vacuum polarization by electric fields is a well established fact. Assuming that anti-matter has negative gravitational properties, the fluctating electric dipoles from the quantum vacuum may also have gravitational dipolar properties. A model is developed that describes how electric fields could gravitationally polarize the vacuum causing gravitational screening or anti-screening effects. This leads to a violation of the Weak Equivalence Principle or a general mass change most notabily for elementary particles, such as the electron or positron, below but close to measured boundaries. Also a gravitational vacuum torque is predicted to act on a charged capacitor perpendicular to a gravitational field. The predictions could be verified by future laboratory experiments that could contribute on our understanding of the gravitational properties of anti-matter.
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Almandeel, Ali. "Rapidly Locating and Accurately Tracking the Center of Mass Using Statically Equivalent Serial Chains." University of Dayton / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1449255542.
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Cornwell, Varela Edward Neville. "Reconstrucción del equivalente en agua de nieve mediante imágenes MODIS incorporadas a un balance de masa - energía." Tesis, Universidad de Chile, 2012. http://www.repositorio.uchile.cl/handle/2250/112347.
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Magíster en Ciencias de la Ingeniería, Mención Recursos y Medio Ambiente HídricoIngeniero Civil
La disponibilidad del recurso hídrico en Chile central está relacionada con el volumen total de deshielo proveniente de las cuencas nivales, especialmente en el periodo de estiaje. Por este motivo, surge la necesidad de entender los procesos físicos relacionados con el derretimiento y cuantificar el volumen de agua contenido en el manto nival. El presente estudio propone un modelo de reconstrucción retrospectiva distribuido a escala diaria del equivalente en agua de nieve (SWE, por sus siglas en inglés) contenido en el manto nival considerando el balance de masa - energía propio de la interfaz superficie del manto nival - aire. La modelación incorpora datos meteorológicos locales e información satelital (MODIS) de cobertura nival fraccional y albedo nival. La zona de estudio corresponde a la cuenca Ojos e Agua (39 [Km2]), ubicada en la subcuenca Alta del Aconcagua, Chile. La reconstrucción del SWE propuesta, es aplicada durante la temporada de deshielo de los años 2010 y 2011. Los resultados muestran un volumen máximo de SWE al inicio de la temporada de deshielo de 11 y 16 millones de metros cúbicos respectivamente, valores consecuentes con la disponibilidad hídrica registrada para cada año modelado. Tras la reconstrucción, se procede a la validación del modelo considerando (1) mediciones puntuales del espesor del manto nival y (2) el volumen total de deshielo observado a la salida de la cuenca. La validación muestra que el modelo propuesto solo es capaz de explicar el promedio espacial del SWE observado y la distribución espacial de SWE a una escala mayor a la de ladera, explicando de forma más satisfactoria los volúmenes de deshielo (con un error promedio anual de un 20%). Luego, se estudian diversos aspectos de interés tales como: (1) la influencia de cada forzante meteorológica, parámetro del manto nival y característica fisiográfica incluida en el modelo por medio un análisis de sensibilidad enfocado a la cuantificación del efecto ejercido sobre el flujo de energía total externa, (2) la definición de áreas representativas para la medición en terreno del SWE (ARs) mediante dos enfoques complementarios basados en la representatividad del SWE promedio espacial, obteniendo un área porcentual (2010 y 2011) de un 10% y 17% para ambos enfoques respectivamente, (3) la evaluación de la capacidad predictiva del equivalente en agua de nieve máximo respecto al volumen total de deshielo. El modelo desarrollado es una herramienta potencialmente útil para efectos de predicción y estudio de procesos físicos relacionados con el manto nival, siendo de interés la instrumentación nivométrica ubicada en distintas ARs (definidas según los enfoques propuestos en este estudio) con el propósito de la futura aplicación de modelos de derretimiento de base semi empírica, disminuyendo el error de predicción al mejorar la calidad de la calibración de los parámetros requeridos.
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Wernet, Jack R. "Comparison of the Statically Equivalent Serial Chain Center of Mass Estimation Method to OpenSim's Residual Reduction Algorithm." University of Dayton / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1628009554478147.
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Shakya, Rikesh. "Mass Airflow Sensor and Flame Temperature Sensor for Efficiency Control of Combustion Systems." University of Akron / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=akron1447679976.
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Tajmar, Martin, and Andre Koch Torres Assis. "Influence of Rotation on the Weight of Gyroscopes as an Explanation for Flyby Anomalies." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-197196.
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We consider two models which lead to the prediction of a weight change of gyroscopes depending on the rate of rotation: mass-energy equivalence and Weber's force for gravitation. We calculate the order of magnitude of this effect in both models and show that Weber's model predicts a weight change depending on the spin axis orientation resembling close similarities to observed Earth flyby anomalies. however, our predicted effect is much smaller than the observed effect, which could explain why flyby anomalies were not detected anymore in recent spracecraft trajectories.
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Medina, Alberto Martin Gago. "Soluções de grande comprimento de oscilação para o problema de neutrinos solares." Universidade de São Paulo, 2001. http://www.teses.usp.br/teses/disponiveis/43/43134/tde-04122013-105222/.
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Esta tese apresenta uma análise estatística detalhada dos dados de experimentos com neutrinos solares mais recentes, com duas diferentes soluções para oscilações de neutrinos, ambas caracterizadas por um grande comprimento de oscilação. A primeira baseada no mecanismo de oscilação padrão, ou seja, induzida por massa, sendo esta estudada nos casos de duas e três gerações e dentro do regime de quase-vácuo. E a segunda, uma exótica, que usa como mecanismo de oscilação uma possível violação do princípio de equivalência, que foi analisada somente para o caso de duas gerações, sendo este discutido para transições entre neutrinos ativos, e entre neutrinos ativos e estéreis. Nossos resultados mostraram que ambas soluções são consistentes com os dados de neutrinos solares e, também, no caso específico do quase-vácuo, observamos que a hipótese de três gerações ficou desfavorecida.This thesis presents a well detailed statistical analysis using the recent data from solar neutrino experiments. This analysis was done in the framework of two different solutions of neutrino oscillations, both characterized by a long oscillation wavelength. The first was based on the standard mass induced oscillation mechanism, here we worked in the scheme of two and three neutrino generations within the quasivacuum regime. The second was an exotic mechanism, where the neutrino oscillation is due to a possible breakdown of the equivalence principle, this alternative was analyzed only for two neutrino generations, in the cases for the conversion among active neutrino and active to sterile neutrino. Our results show a good agreement between the solar neutrino data and both solutions, also in the specific case of quasivacuum, we found that the hypothesis for the three neutrino generation is disfavored.
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Fortier, Robin. "Vers un système d'information géographique du couvert nival en Estrie." Mémoire, Université de Sherbrooke, 2010. http://savoirs.usherbrooke.ca/handle/11143/2651.
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The objective of this research is to develop a system capable of simulating snow depth and snow water equivalent in the Sherbrooke to Mount-Megantic area of Quebec's Eastern Townships using meteorological and digital terrain data as input.The working hypothesis is that meteorological data may drive a point energy and mass balance snow cover model.The model used was developed by the Hydrologic Research Lab (National Weather Service) which was calibrated for local conditions using field data collected during two winters at several sites on Mount-Megantic. Snow water equivalent and depth are used for calibration and validation of the model. Automated snow sensors were also used to obtain temperature calibration data.The snow surveys and correction of the air temperature for elevation improves the estimates of snow depth and water equivalent.The results suggest that data from the Sherbrooke meteorological stations can be used to estimate the snow cover over the area of Eastern Townships. Air temperature extrapolation across the field area is a challenge. However the simulated snow cover conforms generally well with data observed at several stations throughout the region.
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Al-Faisali, Nihad. "An Open Source Platform for Controlling the MANOI AT01 Humanoid Robot and Estimating its Center of Mass." University of Dayton / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1399035167.
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Piani, Goffredo. "Sull'interferenza quantistica indotta dal potenziale gravitazionale." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2019. http://amslaurea.unibo.it/19167/.
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Con l’avvento della meccanica quantistica è emerso un nuovo parametro che non ha alcun equivalente nella meccanica classica. La fase di un’onda di materia. Essa è direttamente influenzata dal potenziale cui l’onda è sottoposta, dunque anche dal potenziale gravitazionale.
Colella, Overhauser e Werner in uno storico esperimento del 1975 ne introdussero una modalità di verifica che prevede un’interferometria su di un fascio di neutroni. Infatti, i due rami dell’interferometro, se soggetti a un livello differente di potenziale, producono una figura di interferenza.
In questa tesi sono trattati i vari fattori che influenzano gli esperimenti COW. A fianco degli effetti gravitazionali, vi sono quelli causati dalla rotazione terrestre, quelli dovuti alla deformazione del cristallo interferometrico e quelli introdotti dalla teoria della dynamical diffraction.
Infine viene descritta, una tra le tante, l’applicazione di questa tipologia di esperimenti nella verifica del principio di equivalenza in ambito quantistico.
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Mnasri, Faiza. "Étude du transfert de chaleur et de masse dans les milieux complexes : application aux milieux fibreux et à l’isolation des bâtiments." Thesis, Université de Lorraine, 2016. http://www.theses.fr/2016LORR0169/document.
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Le contexte énergétique international impose de nouvelles orientations au secteur du bâtiment neuf ou en rénovation. Toute nouvelle solution doit être techniquement efficace et respectueuse pour l’environnement. Il s'agit dans ce travail de thèse de réaliser une étude numérique et expérimentale de matériaux de construction biosourcés liés au contexte transfrontalier Lorrain (France-Belgique- Luxembourg). En effet, ce travail intègre une partie du projet européen « Ecotransfaire » mené pour le développement d'une filière durable propre aux éco-matériaux. La sélection des matériaux selon une liste de critères à la fois scientifiques, géographiques et environnementaux a permis de répondre à notre problématique en s'orientant vers l'intégration des matériaux biosourcés pour leurs aspects favorables à l'environnement et à l’efficacité énergétique du bâtiment. Intégrés au bâtiment, ces matériaux sont sujets à plusieurs phénomènes de transfert de chaleur et de masse. Dans un premier temps et pour mieux appréhender ces phénomènes, un modèle de transfert couplé de chaleur, d'air, d'humidité (HAM transfers) est utilisé pour simuler le comportement hygrothermique d’un matériau en bois massif à structure supposée homogène. Ce modèle, mis en œuvre et résolu par la méthode des éléments finis, a été validé par des résultats analytiques retenus dans la littérature. L'étude de sensibilité du modèle au couplage, aux dimensions dans l'espace, aux conditions aux limites et aux variabilités des paramètres d'entrée est également présentée. Une des difficultés de l’utilisation de ce modèle réside dans la prise en considération de l'aspect fortement hétérogène de certains matériaux. Ainsi, dans ce travail, nous proposons une approche de caractérisation d'un composite lignocellulosique hétérogène de structure poreuse. En effet ce matériau est composé de deux constituants bien connus dans le domaine de l’industrie de construction: Le bois et le ciment. Le bois est incorporé sous forme de granulats avec des formes et des tailles irrégulières et le ciment est utilisé comme un liant. Le travail réalisé permet de remonter aux propriétés intrinsèques équivalentes de ce matériau (conductivité thermique et perméabilité à la vapeur) à l’aide des techniques de micro-tomographie. La méthodologie suivie consiste à la détermination de la structure d'échantillon par une prise d'images à l'échelle microscopique. Une fois la structure de l’échantillon générée, une reconstruction de la représentation bidimensionnelle précède la génération de la structure tridimensionnelle à l'aide d’un outil numérique qui permet de déterminer les propriétés équivalentes des domaines reconstruits en 3D. La perméabilité et la conductivité thermique équivalentes sont les deux propriétés évaluées dans cette configuration. Ces deux propriétés dépendent fortement de la porosité et de la distribution des pores dans la phase continue (la phase solide). De plus la composition de ce matériau et les fractions volumiques de chacun de ses constituants influent sur la formation de sa microstructure et par conséquent sur ses propriétés de transferts thermiques et hydriques. L'ensemble des connaissances développées dans ce travail permet une piste sérieuse pour l'élaboration d'un éco-matériau à propriétés contrôlées pour des usages spécifiques dans la construction et la rénovationInternational energy context requires a new orientation to the building sector as in construction or in renovation. Any new solution must be technically efficient and environmentally acceptable. In this thesis, the object is to achieve a numerical and experimental analysis of a building biobased materials. Some of these materials are included from the study of a transborder project to the Lorraine region (France, Belgium and Luxembourg). Indeed an Ecotransfaire project was included in this work. This project has been oriented to the development of a sustainable eco materials chain. A process of analysis has been established in order to select the materials candidates on the basis of scientific, geographical and environmental criteria. The answers are moving towards the integration of bio-based materials. These materials are subject of several heat and mass transfers phenomena. So understanding these mechanisms within a building material has been achieved firstly. This resulted on a coupled model of heat transfer, air, moisture experienced by the HAM model. This model is applied to a wooden building material whose its structure is assumed homogeneous. Then, this model was implemented and solved by the finite element method. Its numerical solution is validated by analytical results available in the literature. The study of sensitivity of the model coupling, dimensions in space, the boundary conditions and the variability of input parameters is also presented. One of the difficulties of using this model is the case of heterogeneous materials. Thus, in this work, we propose an approach of characterization of a heterogeneous lignocellulosic composite material with a porous structure. In fact, this material is composed of two components: Wood and cement. The wood is presented by a shapes aggregates with irregulars sizes and the cement is considered as the binder in the composition. The object was to predict its equivalent intrinsic properties (thermal conductivity and vapor permeability) by using the micro-tomography techniques.The methodology consists to determine the structure of the sample by taking images at the microscopic scale. Once the structure of the sample is generated, we will conduct from a reconstruction of the two-dimensional representation to a three dimensional structure by using a numerical tool which determines the equivalent properties of the 3D reconstructed domain. The permeability as well as the equivalent thermal conductivity are the two properties evaluated in this configuration. These two properties are strongly depend to the porosity and to pore distribution in the continuous phase (the solid one). Moreover the composition of the material and the volume fractions of each components influence the formation of microstructure and consequently the thermal and hydric transfers
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Cavedal, Luiz Eduardo 1974. "Quantificação do clonazepam em plasma humano por cromatografia líquida de alta performance acoplada ao espectrômetro de massas em um estudo de bioequivalência." [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/312668.
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Orientador: Gilberto De NucciDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas
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Resumo: O objetivo foi o desenvolvimento de um método rápido, sensível e específico para quantificar clonazepam em plasma humano. Posteriormente esse método foi utilizado em um estudo de bioequivalência para comparar a biodisponibilidade entre duas formulações de clonazepam comprimidos de 2 mg em 40 voluntários saudáveis de ambos os sexos. Materiais e métodos: O estudo foi conduzido em dois períodos de confinamento dos voluntários, com 18 dias de intervalo entre o primeiro período e o segundo. Os plasmas dos voluntários, após a administração dos medicamentos, foram obtidos em diversos pontos de coleta dentro de um intervalo de 72 horas. As concentrações de clonazepam foram analisadas por cromatografia de fase reversa combinada e espectrometria de massas (LC-MS-MS) com eletrospray de ionização positiva usando o método de monitoramento de ion selecionado. Das curvas de concentração plasmática de Clonazepam vs tempo foram obtidos os seguintes parâmetros farmacocinéticos: Cmax e ASC0-72. Resultados: A média geométrica da relação Clonazepam/ Rivotril? 2 mg foi de 100.30% (90% CI=91.59-109.85%) para Cmax e 101.1% (90% CI=97.60-104.72%) para ASC0-72. Conclusão: Considerando que o CI de 90% (intervalo de confiança) para ambos Cmax e ASC0-72 obedeceram ao intervalo proposto pela Agência Nacional de Vigilância Sanitária (ANVISA) de 80-125%, foi concluído que Clonazepam 2 mg comprimido é bioequivalente ao Rivotril? 2 mg
Abstract: The objective was a development of a rapid, sensitive and specific method for clonazepam quantification in human plasma. This method was used in a bioequivalence study to compare the bioavailability of two clonazepam tablet 2 mg formulations in 40 health volunteers of both sexes. Material and methods: The study was conducted in two-period crossover design and an 18 days washout period. The volunteers plasma samples were obtained, after dose, over several times until 72-hour interval. Clonazepam concentrations were analysed by combined reversed phase liquid chromatography and tandem mass spectrometry (LC-MS-MS) with positive ion electrospray ionisation using selected ion-monitoring method. From the Clonazepam plasma concentration vs time curves the following pharmacokinetic parameters were obtained: Cmax and ASClast. Results: Geometric mean of Clonazepam/ Rivotril? 2 mg individual percent ratio was 100.30% (90% CI=91.59-109.84%) for Cmax and 101.1% (90% CI=97.61-104.72%) for ASC0-72. Conclusion: Since the 90% CI (confidence interval) for both Cmax and ASClast were within the 80-125% interval proposed by the Agencia Nacional de Vigilância Sanitária (ANVISA), it was concluded that Clonazepam 2 mg tablets was bioequivalent to Rivotril? 2 mg, according to both the rate and extent of absorption
Mestrado
Farmacologia
Mestre em Farmacologia
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Yahi, Islem. "Modélisation des sources de rayonnement au sein d'un véhicule automobile avec prise en compte de la présence du plan de masse." Rouen, 2009. http://www.theses.fr/2009ROUES043.
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La thèse, ici présentée, traite des problématiques relatives au domaine de la Compatibilité Électromagnétique automobile. Ce travail porte sur le développement d'un outil de simulation, basé sur la méthode PEEC (Partiel Element Equivalent Circuit), destiné à traiter les problématiques automobiles de câblage. Cet outil de simulation sera un support d'aide à la décision ou à la conception pour les équipementiers ou les constructeurs automobiles. Le manuscrit est divisé en trois parties : dans la première, on justifie le choix d'utilisation de la méthode PEEC et on y étudie la caractérisation fréquentielle des câbles en présence des plans de masse pour. Dans la seconde partie du mémoire, nous détaillons toutes les contributions apportées pour optimiser l'outil existant sur deux aspects principaux : l'élargissement de sa bande de fréquence et l'optimisation de son temps d'exécution. La dernière partie est consacrée à deux applications concrètes : dans la première, on reproduit un processus lié aux mesures en champ proche, relatif à calibrage des sondes de mesure. La seconde application traite d'un cas de câblage automobile, où nous avons pu concrètement tester notre outil de simulation. L'exemple proposé regroupe tous les développements effectués jusque là dans le but d'en montrer la pertinenceThe thesis presented here, deals with the problems relating to the field of automotive Electromagnetic Compatibility. The work deals specifically on the development of a simulation tool based on the PEEC (Partial Element Equivalent Circuit) method, dedicated to the cabling problems in automobiles. This simulation tool would also support the vehicle manufacturers in decision-making or designing their products. The manuscript is divided into three parts: the first justifies the choice of using the PEEC method among the other numerical methods. We examine also the frequency characterization of cabling schematics in the presence of a ground plane. In the second part of the thesis, we detail all the contributions to optimize an existing version of this tool on two main aspects : the expansion of its frequency band and the optimization of its execution time. The last part is devoted to two applications : firstly, we show a process related to near-field measurements, on the calibration of measuring probes. The second application deals with a case study of the cabling in an automobile, in which we could exclusively test our simulation tool. The example includes all the proposed developments made so far in order to demonstrate its relevance
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Zatloukal, Lukáš. "Odlehčení ojnice vznětového řadového čtyřválce." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2008. http://www.nusl.cz/ntk/nusl-227896.
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This diploma thesis applies to the light-weight itself of a connecting rod of a mass-produced tractor-engine. As a one of the most important and first part of this task is creating a 3D simulation model of a connecting rod. The strenght calculation is following skip factor of the light-weight, the exact calculated dimension of relieve is providing by means of an engine imbalance including the connecting rod. The outcome data of research are instrumental to the new relieve and strengthen 3D design. The conclusion and ending point of the diploma thesis evaluate results.
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Kudlík, Michael. "Blok vznětového motoru 2.0L." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2017. http://www.nusl.cz/ntk/nusl-319930.
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This diploma thesis describes the problems of the engine block and crankcase. As a one of the most imprortant and first part of this task is creating a 3D simulation model of a engine block and calculating load forces of engine block. The simulation and evaluation of the solution are calculated by using method finite element, software Ansys. The conclusion and ending point of the od the diploma thesis construction desing of stiffness increase.
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Llerar, Meza Gerónimo. "Upscaling nonreactive solute transport." Doctoral thesis, Universitat Politècnica de València, 2009. http://hdl.handle.net/10251/5848.
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This thesis focuses on solute transport upscaling. Upscaling of solute transport is usually required to obtain computationally efficient numerical models in many field applications such as, remediation of aquifers, environmental risk to groundwater resources or the design of underground repositories of nuclear waste. The non-Fickian behavior observed in the field, and manifested by peaked concentration profiles with pronounced tailing, has questioned the use of the classical advection-dispersion equation to simulate solute transport at field scale using numerical models with discretizations that cannot capture the field heterogeneity. In this context, we have investigated the use of the advection-dispersion equation with mass transfer as a tool for upscaling solute transport in a general numerical modeling framework.
Solute transport by groundwater is very much affected by the presence of high and low water velocity zones, where the contaminant can be channelized or stagnant. These contrasting water velocity zones disappear in the upscaled model as soon as the scale of discretization is larger that the size of these zones. We propose, for the modeling solute transport at large scales, a phenomenological model based on the concept of memory functions, which are used to represent the unresolved processes taking place within each homogenized block in the numerical models.
We propose a new method to estimate equivalent blocks, for which transport and mass transfer parameters have to be provided. The new upscaling technique consists in replacing each heterogeneous block by a homogeneous one in which the parameters associated to a memory functions are used to represent the unresolved mass exchange between highly mobile and less mobile zones occurring within the block. Flow upscaling is based on the Simple Laplacian with skin, whereas transport upscaling is based in the estimation of macrodispersion and mass transfer parameters as a result of the interpretation of the rLlerar Meza, G. (2009). Upscaling nonreactive solute transport [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/5848
Palancia
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Janošková, Lenka. "Dynamická analýza konstrukce zatížené seismickým zatížením." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2013. http://www.nusl.cz/ntk/nusl-226464.
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In this diploma thesis the seismic load on two different models is solved – the first model is a beam hall and the second model is a multistory building. The calculation of seismic load was performed according to standard ČSN EN 1998-1 (Eurocode 8) using the response spectrum analysis and the method of equivalent static forces (substi-tute load). For the combination of seismic responses in different directions are used SRSS and CQC rules. Models and calculations were solved in a student’s version of program RFEM 4.10 (Ing. Software Dlubal, s.r.o.). The comparison of mentioned methods in each models, also the comparison of combinative rules in calculation and the final evaluation of seismic responses on both of models are the subject of this thesis.
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Parkes, Anthony Richard. "The impact of size and location of pool fires on compartment fire behaviour." Thesis, University of Canterbury. Civil and Natural Resources Engineering, 2009. http://hdl.handle.net/10092/3444.
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An understanding of compartment fire behaviour is important for fire protection
engineers. For design purposes, whether to use a prescriptive code or performance
based design, life safety and property protection issues are required to be assessed. The
use of design fires in computer modelling is the general method to determine fire safety.
However these computer models are generally limited to the input of one design fire,
with consideration of the complex interaction between fuel packages and the
compartment environment being simplified. Of particular interest is the Heat Release
Rate, HRR, as this is the commonly prescribed design parameter for fire modelling. If
the HRR is not accurate then it can be subsequently argued that the design scenario may
be flawed. Therefore the selection of the most appropriate fire design scenario is
critical, and an increased level of understanding of compartment behaviour is an
invaluable aid to fire engineering assumptions.
This thesis details an experimental study to enhance the understanding of the impact and
interaction that the size and location of pool fires within an enclosure have upon the
compartment fire behaviour. Thirty four experiments were conducted in a reduced scale
compartment (½ height) with dimensions of 3.6m long by 2.4m wide by 1.2m high
using five typical ventilation geometries (fully open, soffit, door, window and small
window). Heptane pool fires were used, located in permutations of three evenly
distributed locations within the compartment (rear, centre and front) as well as larger
equivalent area pans located only in the centre. This thesis describes the experimental
development, setup and results of the experimental study. To assist in the classification
of compartment fire behaviour during the experiments, a ‘phi’ meter was developed to
measure the time dependent equivalence ratio. The phi meter was developed and
configured to measure O₂, CO₂ and CO. The background development, calibration, and
experimental results are reported. A review of compartment fire modelling using Fire
Dynamics Simulator, has also been completed and the results discussed.
The results of this experimental study were found to have significant implications for
Fire Safety Engineering in that the size of the fire is not as significant as the location of
the fire. The effect of a fire near the vent opening was found to have a significant impact
on compartment fire behaviour with the vent located fuel source increasing the total
compartment heat release rate by a factor of 1.7 to that of a centrally placed pool fire of
the same total fuel area. The assumption that a fire located in the centre of the room
provides for the highest heat release rate is not valid for post-flashover compartment
fires. The phi meter was found to provide good agreement with the equivalence ratio
calculated from total compartment mass loss rates, and the results of FDS modelling
indicate that the use of the model in its current form can not be applied to complex pool
fire geometries.
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Shareef, I. Khader. "Axially Symmetric Equivalents Of Three-Dimensional Rf Ion Traps." Thesis, 2010. http://hdl.handle.net/2005/2243.
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This thesis presents axially symmetric equivalents of three-dimensional rf ion traps. Miniaturization in mass spectrometry has focused on miniaturizing mass analyzers. Decrease in mass analyzer size facilitates reduction of the size of other components of a mass spectrometer, especially the radio frequency electronics and vacuum system. Miniaturized mass analyzers are made using advanced microfabrication techniques. Due to micromachining limitations, it is not possible to fabricate ion traps with exact axial symmetry.
The motivation for this thesis is to investigate newer three-dimensional geometries which do not possess axial symmetry, but are equivalent in performance to axially symmetric ion traps. We introduce a 3D geometry called square ion trap(SIT) having a ring electrode made off our square shaped planar surfaces and square shaped endcap electrodes resembling a cuboid. Initially, a SIT geometry is taken and it will be investigated if this unknown 3D geometry can be made equivalent to a well characterized, axially symmetric ion trap like the CIT. The purpose of showing equivalence will be to understand the ion dynamics and fields inside the new 3D SIT.
This thesis consists of five chapters.
In Chapter 1, we present the necessary background information required to understand the operation of a mass spectrometer. The Paul trap geometry is introduced followed by the derivation of equation of ion motion inside the Paul trap. The Mathieu stability plot and the modes of operation of a mass spectrometer are briefly discussed. The chapter ends by outlining scope of the thesis.
Chapter 2 describes the computational methods employed by us in the thesis. First, the geometry of square ion trap is introduced. Then the boundary element method(BEM) which is used to compute the charge distribution on the electrode surfaces is discussed. This is followed by the three-dimensional Green’s function which should be employed for non-axially symmetric structures. The method to calculate potential and field inside the ion trap from charge distribution is shown. Calculation of multipole coefficients for non-axially symmetric traps using charge distribution is shown. The methods used to generate ion trajectory and stability plot are discussed. The Nelder-Mead simplex method used for optimization is also presented.
To verify our numerical methods of charge calculation, we have taken standard textbook problems and compared our results with those presented therein. The multipoles calculation, field and ion trajectory was verified by comparing the results for the Paul trap and cylindrical ion traps.
Chapter 3 presents the results for axially symmetric equivalents of 3D rf ion traps. SIT geometry of dimensions equivalent to the CIT0 are taken and field and multipoles are studied in it. Then optimization is applied to create a CIT geometry equivalent to the SIT under study. Axial field and ion trajectory was compared and observed to be matching. Finally, stability plot was generated for both SIT and its equivalent CIT and was found to present a close match.
Chapter 4 presents the numerical results obtained for three-dimensional rf ion trap equivalent of CIT. In this chapter, we have considered two standard geometries, the CIT0 and the CITopt. Optimization was applied to create SIT geometries equivalent to the CIT0 and the CITopt respectively. Comparison of fields and ion trajectory confirmed the fact that non-axially symmetric traps can be created equivalent to any axially symmetric ion trap.
We have also considered another case of axially symmetric circular planar ion trap which has an annular ring electrode and two planar endcap electrodes. Square equivalent of circular planar trap was created by the optimizer and its equivalent was verified by ion trajectory comparison.
Chapter 5 summarizes the thesis with a few concluding remarks.
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Tong, Xuan-Wen, and 童瑄文. "Equivalent elastic moduli for a spatially variable soil mass subjected to a simple stress state." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/09498487437368033428.
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Hung, Chao-Lung, and 洪肇隆. "Use of Equivalent-Mass Method for calculating the free vibration characteristics of a rectangular plate carrying multiple three degree-of-freedom spring-mass systems." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/80819636851871140568.
Full textAbstract:
碩士國立高雄海洋科技大學
輪機工程研究所
98
This paper aims at presenting a technique to replace each three-degree-of-freedom (3-dof) spring-mass system (or substructure) by a set of equivalent masses so that the dynamic characteristics of a rectangular plate (or main structure) carrying any number of elastically mounted lumped masses may be obtained from the same plate carrying the same sets of rigidly attached equivalent masses. Because the three degrees of freedom (dof’s) of the substructure are embedded in its equivalent masses, the total dof of the entire vibrating system (i.e, the main structure together with all the substructures) is independent on the total number of the substructures attached to the main structure in the presented equivalent mass method (EMM). However, in the conventional finite element method (FEM), the total dof of the entire vibrating system increases by three when one more substructure is attached to the main structure. Compared with FEM, the merits of EMM are double: Firstly, since the total dof of the entire vibrating system in EMM is smaller than that in FEM, some computer storage memory may be saved. Secondly, since the dof’s for all the substructures are eliminated, the associated natural frequencies and mode shapes are excluded from those of the main structure and some effort required for the analysis of computer-output data may also be saved. It is evident that the last merits of EMM will be more predominant if the total number of substructures attached to the main structure is large.
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Maji, Vidya Bhushan. "Strength And Deformation Behaviour Of Jointed Rocks : An Equivalent Continuum Model." Thesis, 2007. http://hdl.handle.net/2005/545.
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Most rock masses encountered in civil and mining engineering projects contain pre-existing discontinuities. These discontinuities weaken the rock masses to an extent, which depends very much on the size of engineering structure relation to discontinuity spacing. The strength and deformability of rock mass is controlled not only by the intact portion of rock, but by the characteristic of the joints that break up the mass, particularly their pattern and their orientation with respect to the in-situ stresses. In considering the effect of joints, the discrete approach emerged as an efficient tool and advocated since 1970s (Cundall, 1971). However, the numerical approach with modelling the joints explicitly has the limitation of computational complexity for modelling large-scale problems with extremely large number of joints. As an alternative to this limitation, the equivalent continuum approach models the jointed rock masses as a continuum with the equivalent properties that represent implicitly the effects of the joints.
Several numerical methods have been developed by various researchers to model jointed rock masses as equivalent continuum, using various techniques. However, the existing equivalent continuum models are complicated and need more input data from experimental or field testing in order to carry out the analysis. Present approach attempts to use statistical relations, which are simple and obtained after analyzing a large data from the literature on laboratory test results of jointed rock masses. Systematic investigations were done including laboratory experiments to develop the methodologies to determine the equivalent material properties of rock mass and their stress-strain behaviour, using a hyperbolic approach (Duncan and Chang, 1970). Present study covers the development of equivalent continuum model for rock mass right from developing statistical correlations to find out equivalent material properties based on experimental results, to the implementation of the model in FLAC3D for 3-dimensional applications and subsequently verification leading to real field application involving jointed rocks.
Experimental work carried out to study the strength and deformation characteristics of jointed rock by using standard laboratory tests on cylindrical specimens of plaster of Paris by introducing artificial joints. The objective was to derive the compressive strength and elastic modulus of rock mass as a function of intact rock strength/modulus and joint factor. The obtained experimental results and developed relations were compared with the previous experimental data on jointed rocks. Further, a failure criterion as proposed by Ramamurthy (1993) has been validated from these experimental results of intact and jointed rock specimens. Empirical relationships similar to Ramamurthy’s relations are established for the prediction of rock mass strength and were compared with proposed equation by Ramamurthy (1993) and are found comparable. However, the equations by Ramamurthy were based on different variety of rocks and therefore recommended for further use and were used in numerical models.
For efficient application to the field problems the equivalent continuum model is implemented in the program Fast Lagrangian analysis of continua (FLAC3D). The model was rigorously validated by simulating jointed rock specimens. Element tests were conducted for both uniaxial and triaxial cases and then compared with the respective experimental results. The numerical test program includes laboratory tested cylindrical rock specimens of different rock types, from plaster of Paris representing soft rock to granite representing very hard rock. The results of the equivalent continuum modelling were also compared with explicit modelling results where joints were incorporated in the model as interfaces. To represent highly discontinuous system, the laboratory investigation on block jointed specimens of gypsum plaster (Brown and Trollope, 1970) was modelled numerically using equivalent continuum approach.
To extend the applicability of the model to field applications, investigation were done by undertaking numerical modelling of two case studies underground caverns, one Nathpa Jhakri hydroelectric power cavern in Himachal Pradesh, India, and the other one Shiobara hydroelectric power cavern in Japan. This study verifies the efficiency of the present approach in estimating ground movement and stress distribution around the excavations in jointed rock masses. The modelling results were also compared with six other computation models as presented by Horii et al. (1999) for the Shiobara power house cavern. An attempt has also been made to numerically model the support system for the cavern and investigate the efficiency of reinforcements using FLAC3D. The model was also used for analyzing large scale slope in jointed rocks using the equivalent continuum model by undertaking numerical modelling of Anji bridge abutment slopes, in Jammu and Kashmir, India. Slope stability analysis is done using equivalent continuum approach for both, the original profiles as well as with the pier loads on cut profiles. Attempt was also made to exhibit the shear strength dependency of the strain though the hyperbolic stress- strain model. The shear strain developed in the slope increases with reducing the shear strength. The relationship between the shear strength reduction ratio ‘R’ and axial strain ‘ε’, for different values of failure ratio ‘Rf’ was studied and it was observed that, the value of ‘ε’ increases, as the value of ‘R’ increases especially it increases rapidly when the value ‘R’ approaches certain critical value, which varies with the value of ‘Rf’. This critical value of R is known as the critical shear strength reduction factor Rc and is highly sensitive to the confining stress. As the value of Rf increases, representing a transition from linear elastic nature to nonlinear nature, the value of critical shear strength reduction ratio also decreases. Relationship between the critical shear strength reduction ratio and the safety factor were examined to elucidate their physical meaning. It was observed that at critical value of the shear strength reduction ratio, a well defined failure shear zone developed from the toe to the crest of the slope.
Intelligent models using ANNs were also developed to predict the elastic modulus of jointed rocks as an alternative to empirical equations and without predefining a mathematical model to correlate the properties.
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Chang, Ren-Jye, and 張仁傑. "Use of Equivalent Spring Method for Free Vibration Analyses of a Rectangular Plate Carrying Multiple Three-degree-of-freedom Spring-Mass Systems." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/40361217769884614758.
Full textAbstract:
碩士國立高雄海洋科技大學
輪機工程研究所
97
Due to the complexity of mathematical expressions, the literature concerning the free vibration analysis of plates carrying multiple three-degree-of-freedom (dof) spring-mass systems is rare. In this paper, the three degrees of freedom (dof’s) for a spring-mass system refer to the translational motion of its lumped mass in the vertical ( ) direction and the two pitching motions of its lumped mass about the two horizontal ( and ) axes. The basic concept of this paper is to replace each three-dof spring-mass system by a set of equivalent springs, so that the free vibration characteristics of a rectangular plate carrying any number of three-dof spring-mass systems can be obtained from those of the same plate supported by the same number of sets of equivalent springs. Since the three dof’s of the lumped mass for each three-dof spring-mass system are eliminated to yield a set of equivalent springs, the total dof of the entire vibrating system is not affected by the total number of the spring-mass systems attached to the rectangular plate. However, this is not true in the conventional finite element method (FEM), where the total dof of the entire vibrating system increases three if one more three-dof spring-mass system is attached to the rectangular plate. Hence, the computer storage memory required by using the presented equivalent spring method (ESM) is less than that required by the conventional FEM, and the more the total number of the three-dof spring-mass systems attached to the plate, the more the advantage of the ESM. In addition, since manufacturing a spring with the specified stiffness is much easier than making a three-dof spring-mass system with the specified spring constants and mass magnitude, the presented theory of replacing a three-dof spring-mass system by a set of equivalent springs will be also significant from this viewpoint.
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Garber, Letal. "The Relationships Between Energy Balance, Timing and Quantity of Protein Consumption, and Body Composition in Collegiate Football Players." 2016. http://scholarworks.gsu.edu/nutrition_theses/79.
Full textAbstract:
Background Timing and quantity of protein (PRO) consumption are important considerations for muscle protein synthesis (MPS), fat-free mass (FFM) accretion, and body fat % (BF%) reduction. The effect of PRO ingestion on changes in FFM is mediated by many variables. Past studies have focused on specific composition of carbohydrate (CHO) and PRO consumption (CHO vs. PRO + CHO), and have also investigated PRO intake timing at pre-exercise, post-exercise, or both. Other studies have investigated FFM maintenance and growth with increased PRO consumption during catabolic or anabolic phases of energy balance (EB). These mechanisms have been studied in various populations, including healthy untrained individuals, overweight and obese people, and endurance athletes. However, studies have not explored relationships between the amount and timing of PRO ingested, and the state of EB, as it relates to FFM%. Method/Design A retrospective analysis design was used to assess relationships between PRO ingestion, timing, and EB on FFM in collegiate football players. Subjects were members of an intercollegiate Division 1 football team, had completed a one-day food and activity record, and had body composition assessed as part of a regular team screening procedure. Data acquisition was supervised by a PhD/Registered Dietitian. Food and activity records were analyzed using NutriTiming®, which predicts RMR via the Harris-Benedict equation, uses a MET-based relative intensity activity scale, and accesses the USDA Nutrient Database for Standard Reference, Release 26 to predict hourly EB and PRO consumption. EB was assessed as ±400 kcal EB (EBR), < 0 kcal EB (NEGEB), and > 0 kcal EB (POSEB). Total useable PRO (TUP) was defined as the sum of PRO consumed in units up to 30g max/meal, a value also assessed relative to EB at the time of ingestion. The goal was to assess the amount and timing of PRO intake with EB as these factors relate to FFM. Results Pearson's correlations found that BF% was negatively associated with TUP while in EBR (r=-.253; p=0.049), and FFM% was positively associated TUP in EBR (r=0.279; p=0.030) and in POSEB (r=0.282; p=0.028). NEGEB was positively associated with BF% (r=0.325; p=0.011), and negatively associated with FFM% (r=-0.322; p=0.011). Conclusions Results elucidate that players who ingest PRO in a relatively good energy-balanced state had higher FFM% and a lower BF%. Further, those players consuming TUP while in POSEB had an even stronger positive association with FFM% and a stronger inverse association with BF%. These data reject the null hypothesis that football players who consume PRO in POSEB have less FFM% than those who consume PRO in NEGEB.
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Bouqentar, Lamiae. "Les articulations de l'arabité et du genre à travers les chaines d'équivalence : le cas de Uprising of Women in the Arab World." Thèse, 2014. http://hdl.handle.net/1866/11973.
Full textAbstract:
Ce mémoire de maîtrise s’intéresse aux nouvelles expressions protestataires qui ont émergé après les soulèvements connus sous le « printemps arabe » en prenant, comme objet d’analyse, Uprising of Women in the Arab World (UWAW), une page Facebook qui œuvre pour les droits des femmes à travers le « monde arabe ». Ce travail propose de saisir cette page Facebook à travers les croisements d’enjeux d’arabité et de genre, dans une perspective discursive critique. La notion d’arabité désigne une appartenance commune au
« monde arabe » qui reposerait sur la production de référents religieux et linguistiques partagés par l’ensemble des pays arabes. Le genre est abordé comme un langage privilégié pour signifier les rapports de pouvoir (Scott, 1988). Afin de mettre en lumière les différentes intersections de l’arabité et du genre, je propose de recourir au concept d’articulation (Hall, 1980). Ce dernier réfère à l’assemblage de différentes pratiques de production qui constituent un discours. Cette mise en relation, non-nécessaire, s’effectue dans une conjoncture régie par les forces hégémoniques du moment. Ainsi, le concept d’articulation permet d’explorer ce que font dans leur (co)présence les discours hétérogènes par et dans lesquels l’arabité et le genre sont rendus visibles dans et à travers la page UWAW.
Ces articulations sont questionnées à partir du concept de chaine d’équivalence de Laclau (2008) qui désigne une condensation de revendications hétérogènes, à travers des relations d’équivalence et de différence. Ces dernières se produisent à travers l’affirmation des particularités des revendications, tandis que les relations d’équivalence sont basées sur la mise en avant de la communalité des revendications.
Cette recherche est guidée par la proposition de recherche suivante : UWAW peut être comprise comme un espace discursif traversé par des chaines d’équivalences où les articulations de l’arabité et du genre se matérialiseraient selon des relations d’équivalence et de différence. Elle fait l’objet d’une analyse critique de trois campagnes ayant eu cours sur l’UWAW en 2014. Ces dernières sont abordées comme des lieux de discours, soit des espaces construits dans et par un recours à des discours spécifiques qui participent à la production de savoirs situés dont ils sont aussi, de quelque manière, les produits. Ainsi, l’analyse s’attarde à comprendre comment la production de sens repose sur des discours concurrentiels qui puisent dans des savoirs différents qu’ils contribuent à faire circuler.
L’analyse démontre la grande hétérogénéité de l’arabité qui s’est manifestée sous un visage distinct dans chaque campagne. Elle est homogénéisée et universalisée dans Do You know, clivée dans Israël Apartheid Week, et citoyenne dans « Je ne resterai pas silencieuse ». Le genre est davantage stabilisé, puisqu’il agit principalement comme force universalisante dans les trois campagnes.This master’s thesis is concerned with the aftermath of the popular protests that have emerged in light of the « Arab Spring ». It addresses these issues by means of an analysis of the « Uprising of Women in the Arab World », a Facebook page that deals with women’s rights in the « arab world ». From a critical discursive standpoint, the research attempts to grasp the dynamics of this feminist collective through the lens of arabity and gender. On the one hand, the notion of arabity refers to a common belonging to the « arab world » that stems from the production of common religious and linguistic signifiers. On the other hand, gender refers to a privileged language used to signify power relations (Scott, 1988). I examine the intersections of gender and arabity through the concept of articulation (Hall, 1980) considered as the non-necessary assemblage of different production practices and hegemonic forces of a particular epoch that constitute a discourse. I use this concept of articulation to explore the intersections of different discourses through and by which gender and arabity are produced in the UWAW page. These articulations are analysed through the concept of chains of equivalence (Laclau, 2008), a concept that designates the aggregation of competing claims based on relations of equivalence and relations of difference. The latter are produced through the affirmation of the claims ‘particularity, while the former are constituted through the display of the claims' communalities. This research is guided by the following research proposal: UWAW can be understood as a discursive space constituted by chains of equivalence where articulations of arabity and gender are materialized through relations of difference and relations of equivalence. This proposal is explored through a critical discourse analysis of three of the campaigns that took place on the UWAW in 2014. Focusing on these campaigns as discursive spaces where competing and heterogeneous statements emerge, I examine how the production of meaning is both impacted and informed by the competing knowledges brought to the fore by UWAW. The analysis suggests that arabity is configured differently in each campaign. It is homogenized and universalized in « Do You Know », cleaved in « Israel Apartheid Week » and framed in civic terms in Je ne resterai pas silencieuse. Gender appears to be much more stable as it operated, for the most part, as a universalizing force throughout the campaigns.