Tesis sobre el tema "Rotational loss"
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KHAN, MAHMOOD. "Experimental and Theoretical Analysis of Soft Magnetic Materials for Power applications". Doctoral thesis, Politecnico di Torino, 2017. http://hdl.handle.net/11583/2669467.
Texto completoHegrová, Michaela. "Vliv etherů celulózy na reologické vlastnosti vápna". Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2018. http://www.nusl.cz/ntk/nusl-371927.
Texto completoSchultz, Frederick William. "Loss of rotation of a rotating two-body tethered spacecraft, analytical and experimental techniques". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape3/PQDD_0019/MQ48473.pdf.
Texto completoSchultz, Frederick William Carleton University Dissertation Engineering Mechanical and Aerospace. "Loss of rotation of a rotating two-body tethered spacecraft-analytical and experimental techniques". Ottawa, 1999.
Buscar texto completoCruz, López Pedro Gerson, Palomino Christian Castro, Quintana Clarisse Giannina Palomino, Montero Diego Vingerhoets y Siccha Giancarlo Alberto Morote. "Identificación de los principales factores de rotación de los millennials de puestos administrativos en empresas de Lima metropolitana". Master's thesis, Universidad Peruana de Ciencias Aplicadas (UPC), 2019. http://hdl.handle.net/10757/648660.
Texto completoAbstrac: Once and for different reasons the word millennials have been heard and read in different fields, whether personal, professional or academic. The members of this generation stand out for their adaptation to change, their high self-esteem, their familiarity with technology and their contribution with new ideas about a particular activity. This generation currently represents a quarter of the Peruvian population, which is equivalent to eight million inhabitants, who have very particular interests in relation to work, quality of life and personal development. Their relationship capacity is different from that of other generations, they are pending the latest communication trends; Connectivity is part of your being, it is the generation of speed, from the here and now. However, being always aware of new technologies and new processes mean that millennials do not feel comfortable in an organization that does not challenge them especially when they have been working for more than two or three years. Given this, labor turnover is a problem that all organizations worldwide must face, even more, large companies, where most of their employees are represented by this generation. These companies must ask themselves what or what are the reasons why this staff rotates from work to work, but not before recognizing in their organization the true millennial to know the type of leadership that the bosses must apply to have them and retain them within their team. The time for the millennial generation is worth a lot, largely because they have grown up watching their parents and grandparents dedicating most of their lives to work, their families have lived to work and this generation seeks to change this concept, based on the balance between Work and its quality of life. This research work will search through research, surveys, interviews, tables, theories and statistical tables to know what are the main reasons why this group tends to change companies in the short term and what actions organizations should take to retain them.
Trabajo de investigación
Guillaud, Étienne. "Contribution vestibulaire au contrôle des mouvements du bras lors d'une rotation du corps". Thesis, Université Laval, 2006. http://www.theses.ulaval.ca/2006/23976/23976.pdf.
Texto completoRecent studies in human motor control have shown that vestibular signals can be used to control goal directed arm movements when an unexpected body displacement occurs during the movement. In this thesis, we investigated the specific functions of the vestibular signals to this control, and the mechanisms that are involved. This was done through behavioural studies performed with healthy human subjects and one deafferented patient, and biomechanical modelling. Our results highlight the remarkable computationnal capabilities of the brain which can process vestibular information to predict the consequences of body rotation on reaching movements. The vestibular control of arm movement i) is characterised by short latencies, ii) operates efficiently in darkness, iii) is largely automatic and iv) defines the temporal aspect of the movement. The control of the arm through vestibular information has therefore common characteristics with the vestibular control of ocular, cephalic and postural movements. Our findings bring important new insights about the functions of the vestibular because they suggest that there is a general principle underlying the contribution of vestibular signal to motor control. Keywords: Arm movements, Body rotation, Vestibular information, Multisensorial integration, Biomechanical modelling, Deafferentation.
Guillaud, Etienne. "Contribution vestibulaire au contrôle des mouvements du bras lors d'une rotation du corps". Aix-Marseille 2, 2006. http://theses.univ-amu.fr.lama.univ-amu.fr/2006AIX22063.pdf.
Texto completoRecent studies in human motor control have shown that vestibular signals can be used to control goal directed arm movements when an unexpected body displacement occurs during the movement. In this thesis, we investigated the specific functions of the vestibular signals to this control, and the mechanisms that are involved. This was done through behavioural studies performed with healthy human subjects and one deafferented patient, and biomechanical modelling. Our results highlight the remarkable computationnal capabilities of the brain which can process vestibular information to predict the consequences of body rotation on reaching movements. The vestibular control of arm movement i) is characterised by short latencies, ii) operates efficiently in darkness, iii) is largely automatic and iv) defines the temporal aspect of the movement. The control of the arm through vestibular information has therefore common characteristics with the vestibular control of ocular, cephalic and postural movements. Our findings bring important new insights about the functions of the vestibular because they suggest that there is a general principle underlying the contribution of vestibular signal to motor control
Ibáñez, Usach Carmen. "FIRE RESPONSE ANALYSIS OF CIRCULAR CONCRETE FILLED TUBULAR COLUMNS AND THE EFFECTS OF AXIAL AND ROTATIONAL RESTRAINTS". Doctoral thesis, Universitat Politècnica de València, 2016. http://hdl.handle.net/10251/60150.
Texto completo[ES] Combinar diferentes materiales en un único elemento estructural para aprovechar las fortalezas individuales de cada uno es una práctica consolidada con éxito en el sector de la construcción. En los pilares tubulares de acero rellenos de hormigón (CFT) la acción conjunta del acero y el hormigón presenta muy buenas cualidades a temperatura ambiente: alta capacidad de carga con secciones pequeñas, buena apariencia, alta rigidez y ductilidad y bajo coste de puesta en obra. En las últimas décadas, el uso de pilares CFT en el sector de la construcción, especialmente en edificios de gran altura, ha aumentado no solo debido a sus buenas características a temperatura ambiente sino también por su inherente alta resistencia al fuego. Además, las secciones de pilares CFT son muy versátiles ya que admiten diferentes tipos de relleno, como hormigón en masa, con armaduras o reforzado con fibras; y también una amplia variedad de formas. Aunque los perfiles tubulares más usados son los circulares y rectangulares, nuevas configuraciones están continuamente en desarrollo junto con nuevos materiales. El comportamiento de los pilares CFT a temperatura ambiente ha sido ampliamente estudiado y, a su vez, las investigaciones sobre su comportamiento a fuego han aumentado. Para su análisis estructural, el pilar puede ser considerado como un elemento aislado o como un elemento integrado en una estructura que interactúa con otros elementos estructurales. La revisión del estado del arte en el área de los pilares CFT sometidos a fuego llevado a cabo en el marco de esta tesis ha puesto de manifiesto que la mayoría de los trabajos cubren la respuesta a fuego de elementos aislados y que los estudios existentes sobre pilares en estructuras difieren en sus propuestas y conclusiones. En esta tesis, la respuesta a fuego de pilares CFT se analiza por medio de un modelo de elementos viga con integración por fibras. En primer lugar, se implementa un modelo térmico realista para ser integrado en el modelo termo-mecánico desarrollado cuya precisión se valida con resultados experimentales después de ser calibrado. Un estudio paramétrico se lleva a cabo con el objeto de estudiar los principales factores que afectan al problema y desarrollar un modelo simplificado de cálculo basado en el Eurocódigo 4 Parte 1-1 y que emplea el concepto de sección equivalente del núcleo de hormigón. Finalmente, dado el reducido coste computacional del modelo de fibras, se investigan los efectos de la restricción axial y rotacional en la respuesta frente al fuego de los pilares CFT integrando la columna expuesta a fuego dentro de una subestructura. Se ejecuta un estudio paramétrico para extraer conclusiones sobre esta interacción y contrastar las prescripciones de la normativa actual. El alcance de esta tesis queda limitado a pilares CFT sin protección externa, de sección circular y sometidos a carga axial centrada.
[CAT] Combinar distints materials en un únic membre estructural per a aprofitar les fortaleses individuals de cada u és una pràctica consolidada amb èxit en el sector de la construcció. En els pilars tubulars d'acer omplerts de formigó (CFT) l'acció conjunta de l'acer i el formigó presenta molt bones qualitats a temperatura ambient: alta capacitat de càrrega amb seccions xicotetes, bona aparença, alta rigidesa i ductilitat i baix cost de posada en obra. En les últimes dècades, l'ús de pilars CFT en el sector de la construcció, especialment en edificis de gran altura, ha augmentat no sols degut a les seues bones característiques a temperatura ambient, sinó també per la seua inherent alta resistència al foc. A més, les seccions de pilars CFT són molt versàtils, doncs admeten distints tipus de farcit, com formigó en massa, amb armadures o reforçat amb fibres; i també una àmplia varietat de formes. Encara que els perfils tubulars més usats són els circulars i rectangulars, noves configuracions estan contínuament en desenvolupament junt amb nous materials. El comportament dels pilars CFT a temperatura ambient ha sigut àmpliament estudiat i, al mateix temps, les investigacions sobre el seu comportament a foc han augmentat. Per a la seua anàlisi estructural, el pilar pot ser considerat com un element aïllat o com un element integrat en una estructura que interactua amb altres elements estructurals. La revisió de l'estat de l'art en l'àrea dels pilars CFT sotmesos a foc, duta a terme en el marc d'aquesta tesi, ha posat de manifest que la majoria dels treballs cobreixen la resposta a foc d'elements aïllats, i que els estudis existents sobre pilars en estructures difereixen en les seues propostes i conclusions. En aquesta tesi, la resposta a foc de pilars CFT s'analitza mitjançant un model d'elements biga amb integració per fibres. En primer lloc, s'implementa un model tèrmic realista per a ser integrat en el model termo-mecànic desenvolupat, i la seua precisió es valida amb resultats experimentals desprès de ser calibrat. Un estudi paramètric es du a terme amb l'objectiu d'estudiar els principals factors que afecten al problema i desenvolupar un model simplificat de càlcul basat en l'Eurocodi 4, Part 1-1 i que empra el concepte de secció equivalent del nucli de formigó. Finalment, tenint en compte el reduït cost computacional del model de fibres, s'investiguen els efectes de les restriccions axial i rotacional en la resposta a foc dels pilars CFT integrant la columna exposada a foc dins d'una subestructura. Un estudi paramètric s'executa per a obtenir conclusions sobre aquesta interacció i contrastar les prescripcions de la normativa actual. L'abast d'aquesta tesi queda limitat a pilars CFT sense protecció externa, de secció circular i sotmesos a càrrega axial centrada.
Ibáñez Usach, C. (2016). FIRE RESPONSE ANALYSIS OF CIRCULAR CONCRETE FILLED TUBULAR COLUMNS AND THE EFFECTS OF AXIAL AND ROTATIONAL RESTRAINTS [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/60150
TESIS
Premiado
Celse-Giot, Carole. "Influence du degré d'habileté motrice lors d'un amorçage visuomoteur chez les sujets droitiers manuels". Nice, 2008. http://www.theses.fr/2008NICE2005.
Texto completoSorgun, Mehmet. "Modeling Of Newtonian Fluids And Cuttings Transport Analysis In High Inclination Wellbores With Pipe Rotation". Phd thesis, METU, 2007. http://etd.lib.metu.edu.tr/upload/12612385/index.pdf.
Texto completoNatural Gas Engineering Flow Loop using water and numerous drilling fluids for hole inclinations from horizontal to 60 degrees, flow velocities from 0.64 m/s to 3.05 m/s, rate of penetrations from 0.00127 to 0.0038 m/s, and pipe rotations from 0 to 120 rpm. Pressure loss within the test section and stationary and/or moving bed thickness are recorded. New friction factor charts and correlations as a function of Reynolds number and cuttings bed thickness with the presence of pipe rotation for water and drilling fluids in horizontal and deviated wellbores are developed by using experimental data. Meanwhile empirical correlations that can be used easily at the field are proposed for predicting stationary bed thickness and frictional pressure loss using dimensional analysis and the effect of the drilling parameters on hole cleaning is discussed. It has been observed that, the major variable influencing cuttings transport is fluid velocity. Moreover, pipe rotation drastically decreases the critical fluid velocity that is required to prevent the stationary cuttings bed development, especially if the pipe is making an orbital motion. A decrease in the pressure loss is observed due to the bed erosion while rotating the pipe. Cuttings transport in horizontal annulus is modeled using a CFD software for different fluid velocities, pipe rotation speeds and rate of penetrations. The CFD model is verified by using cuttings transport experiments. A mathematical model is also proposed to predict the flow characteristics of Newtonian fluids in concentric horizontal annulus with drillpipe rotation. The Navier-Stokes equations of turbulent flow are numerically solved using finite differences technique. A computer code is developed in Matlab 2007b for the proposed model. The performance of the proposed model is compared with the experimental data which were available in the literature and gathered at METU-PETE Flow Loop as well as Computational Fluids Dynamics (CFD) software. The results showed that the mechanistic model accurately predicts the frictional pressure loss and the velocity profile inside the annuli. The model&rsquo
s frictional pressure loss estimations are within an error range of ±
10%.
Mathieu, Daniel. "Etude de la dynamique d'étalement de fluides newtoniens et non newtoniens lors d'un processus d'enduction par rotation". Mulhouse, 1997. http://www.theses.fr/1997MULH0468.
Texto completoCaissié, André. "Étude des transferts intermodaux lors de taches de rotation mentale : spécificité tactile, indépendance sensorielle ou dépendance visuelle ?" Thesis, Poitiers, 2012. http://www.theses.fr/2012POIT5002/document.
Texto completoThe work presented in this dissertation is based on the combination of two research paradigms in the field of cognitive psychology: mental rotation and intermodal/inter-task transfer of learning. In our first study (Experiments 1a, 1b, 1c, 2a, and 2b), the objective was to evaluate the processing dependence/independence of visual and tactile information during two mental rotation tasks: the Mental Rotation Test (Vandenberg & Kuse, 1978) and an object mental rotation task (Shepard & Metzler, 1971). Using an intra-subject experimental design, we compared four experimental conditions including intramodal learning: 1. Visual-Visual ; 2. Tactile-Tactile, and intermodal transfer: 3. Visual-Tactile ; 4. Tactile-Visual. Subjects performed two successive tasks in similar perceptual conditions or different perceptual conditions (session 1 and session 2). Our results revealed that mental rotation can depend on treatment processes of mental representations specific to the perceptual modality being used. The information derived from visual prior experience can be used in the tactile condition, whereas we observed few significant tactile transfers in the visual condition. Visual and tactile treatments on complex three-dimensional objects thus permit specific mental imagery strategies (Visual-Visual-IM vs. Tactile-Spatial-IM), derived from different perceptual exploration strategies (visual-global vs. tactile-spatial)
Neilson, Hilding R. y Richard Ignace. "Period Change and Stellar Evolution of β Cephei Stars". Digital Commons @ East Tennessee State University, 2015. https://dc.etsu.edu/etsu-works/2689.
Texto completoArriagada, César. "Rotations tectoniques et déformation de l'avant arc des Andes centrales au cours du Cénozoïque = Rotaciones tectónicas y deformación del antearco en los Andes centrales durante el cenozoico /". Rennes : Géosciences Rennes, Université de Rennes 1, 2004. http://catalogue.bnf.fr/ark:/12148/cb392302035.
Texto completoMention parallèle de titre ou de responsabilité : Rotaciones tectónicas y deformación del antearco en los Andes centrales durante el cenozoico. Textes en français et en anglais. Bibliogr. p. 301-308. Notes bibliogr. Résumé en français, en anglais et en espagnol.
Salazar-Prado, Talia-Milagros. "Identificación de los factores que determinan la alta rotación del personal de ventas en empresas de retail de prendas de vestir: caso tiendas Piero". Bachelor's thesis, Universidad de Lima, 2016. http://repositorio.ulima.edu.pe/handle/ulima/1724.
Texto completoTrabajo de investigación
Aucalla, Taira Sheyla Eunice y Cordova Olenka Valeria Benavente. "Impacto de la satisfacción laboral en la intención de rotación del personal millennials en los fast food de Lima Centro". Bachelor's thesis, Universidad Peruana de Ciencias Aplicadas (UPC), 2019. http://hdl.handle.net/10757/653313.
Texto completoEn el sector Fast Food, se reconoce a la rotación laboral como una relevante problemática, no obstante, esta variable es precedida por la intención que tiene el trabajador de desistir de manera voluntaria a una compañía. Por esta razón, el presente estudio busca identificar cuál es el impacto de la satisfacción laboral y la relación que mantiene con la intención de rotación del personal Millennials en los Fast Food de Lima Centro. Esta investigación aplicó un diseño de enfoque no experimental y transversal en el que se obtuvo una muestra de 372 colaboradores Millennials que laboran en los Fast Food de Lima Centro con el objetivo de identificar el impacto de la satisfacción laboral de estos colaboradores y la relación de esta variable con la intención de rotación del personal. De este modo, se empleó como instrumento a la “Escala de Satisfacción Laboral SL-SPC” (Palma, 1999) y el cuestionario de “Intención de Rotación Laboral” (Jacobo & Roodt, 2008). Se pudo identificar que las siete dimensiones de satisfacción laboral presentan relaciones negativas e impactan significativamente en la intención laboral del colaborador. En otras palabras, a medida que se incrementa el nivel de satisfacción del trabajador Millennials en los Fast Food de Lima Centro, se reduce su intención de rotación laboral. Cabe mencionar, que el objetivo de la investigación es contribuir con estudios del sector fast food y el segmento millenials, ya que actualmente no se cuenta con información o estudios suficientes en Perú que hagan hincapié a los temas desarrollados en el transcurso de la tesis.
In the Fast Food sector, labor turnover is recognized as a relevant problem, however, this variable is preceded by the intention of the worker to voluntarily withdraw from a company. For this reason, the present study seeks to identify the impact of job satisfaction and the relationship it maintains with the intention of rotating Millennials in Fast Food in Lima Centro. The present investigation would use a design of non-experimental and transversal focus in which a sample of 372 Millennials collaborators working in Fast Food of Lima Centro was obtained with the objective of identifying the impact of job satisfaction on the intention of staff turnover. For this reason, the questionnaire of "SL-SPC Job Satisfaction Scale" (Palma, 1999) and the questionnaire "Intention of Labor Rotation" (Jacobo & Roodt, 2008) were used. Therefore, it could be concluded that the seven dimensions of job satisfaction present negative relationships and have a considerable impact on the intention of labor rotation. In other words, as the level of satisfaction of the Millennial worker in Fast Food in Lima Centro increases, their intention of labor rotation is reduced. It should be noted that the objective of the research is to contribute to studies of the fast food sector and the millennial segment, since there is currently no specific information or studies in Peru that emphasize the topics developed during the thesis.
Tesis
Aquice, Quispe Julio Cesar, JoséJuan Mamani y Carrillo Meira Peña. "Pérdida de fidelidad de los clientes, por la alta rotación de personal del área de negocios en las instituciones especializadas en microfinanzas. (ciudad Arequipa)". Master's thesis, Universidad Peruana de Ciencias Aplicadas (UPC), 2019. http://hdl.handle.net/10757/625988.
Texto completoJob rotation in companies in the Microfinance sector in Arequipa has generated special interest, turnover in the Business Area, specifically the position of Credit Analysts, because they have a direct impact on the loss of customer loyalty; At the same time, it generates different effects in the following areas of the company: in the area of human talent, recruitment, training and Impact costs are generated in the work environment; In the Business area, reduction of the loan portfolio, loss of clients, increase of the overdue portfolio, delay in the achievement of goals and reduction of profitability The rotation occurs between Banks (specialized in Microfinance), Financial, Municipal Savings Banks, Rural Savings Banks, Edpymes and Cooperatives, this rotation generates mainly three effects: (1) loss of clients, due to debt purchases; (2) decrease in the level of exclusivity, customers begin to have credit with other entities; (3) Over-indebtedness, increase your credit amount, maintaining your ability to pay The present research work will be based on a qualitative approach, finding that the rotation in the business area in the position of Credit Analyst, in the microfinance sector in the province of Arequipa, is caused by personal and Organizational type; This problem makes it necessary to identify the reasons for the rotation and be able to propose solutions, and to reduce the turnover of the Credit Analyst position, this will allow the loyalty loss of the clients to be mitigated. Therefore, this research work will review literature on Human Resources Management, Articles and studies on Staff turnover, which will allow finding suitable solutions to this problem.
Trabajo de investigación
Yáñez, Siller Federico A. "Variabilidad de diferentes tecnicas quirúrgicas al establecer la rotación de los componentes en la artroplastia total de rodilla y su correlación clínica". Doctoral thesis, Universitat Autònoma de Barcelona, 2021. http://hdl.handle.net/10803/673381.
Texto completoLa adecuada alineación rotacional de los componentes es una de las claves para un buen resultado clínico y una adecuada supervivencia a largo plazo de la ATR (Berger, 1998; Bedard, 2011). Se han descrito distintas técnicas para analizar la alineación rotacional, casi todas ellas utilizando los cortes axiales en la tomografía axial computarizada (TAC), aunque no hay consenso a cerca de cual es la mejor o mas reproducible (Van Houten, 2018). Existen diferentes técnicas quirúrgicas para establecer la rotación de los componentes, las más utilizadas son: la resección anatómica (MR), el uso de sensores de fuerza para equilibrado de espacios (FS_STB) y la técnica asistida por ordenador o navegada (CAS_GB). Es controvertido el hecho de si alguna técnica quirúrgica es superior a otra al momento de establecer la alineación rotacional o que alineación rotacional es la mas adecuada. Este estudio se divide en dos partes. La primera parte, analiza 9 técnicas medición en 2D-TAC para determinar la rotación del componente femoral, tibial y de la ATR en su conjunto. Se estudiaron 27 pacientes y se estudiaron 9 ángulos de rotación, se hicieron dos mediciones de cada ángulo, por tres observadores independientes para calcular la variabilidad intra e inter observador, además de analizó la relación con los resultados clínicos. La segunda parte, es un estudio prospectivo, aleatorizado en la que se incluyeron 60 pacientes distribuidos en tres grupos según la técnica quirúrgica analizada: MR, CAS_GB y FS_STB. Se realizaron 3 mediciones en 2D-TAC: rotación femoral (BFA) y rotación de la rodilla (TE_PTCA y BC_PTCA). Se analizó que técnica quirúrgica reproduce mejor la rotación de la rodilla nativa y el resultado clínico (KSS y WOMAAC) y que técnica quirúrgica proporciona mejores resultados clinicos. En el primer estudio, los resultados muestran que para el componente femoral la técnica mas reproducible es la descrita por Berger en 1993, para el componente tibial es la técnica de el ángulo anatómico de la tibia (ATA). En cuanto a la rotación de la ATR, la técnica mas reproducible es el BC_PTCA y la TE_PTCA que relaciona el eje bicondileo posterior y el eje transepicondileo con el margen posterior de plato tibial. El ángulo BC_PTCA se relaciona significativamente con el resultado clínico según KSS. En el segundo estudio, se apreció que las tres técnicas quirúrgicas no tenían diferencias de rotación preoperatoria y reprodujeron el BFA nativo. La técnica FS_STB y la CAS_GB reproducen el TE_PTCA y la FS_STB reproduce el BC_PTCA. Así mismo, el KSS_FUNCTIONAL fue significativamente mejor en la técnica FS_STB respecto a las otras dos. En conclusión, nuestros resultados confirman que en la medición por 2D-TAC el Angulo de rotación femoral (BFA) fue el mas reproducible y que los ángulos tibiales son poco reproducibles a excepción del ATA. Los ángulos de rotación de la rodilla presentan una buena reproducibilidad y se correlacionan bien con la clínica. La utilización de un sensor de fuerzas permite reproducir la rotación nativa de la rodilla (TE_PTCA y BC_PTCA) y alcanzar unos resultados clínicos significativamente mejores (KSS) que las otras técnicas quirúrgicas estudiadas (MR y CAS_GB).
Adequate rotational alignment of the components is one of the keys to a good clinical outcome and adequate long-term survival of TKA (Berger, 1998; Bedard, 2011). Different techniques have been described to analyze rotational alignment, almost all of them using axial slices in computerized axial tomography (CT), although there is no consensus about which is the best or most reproducible (Van Houten, 2018). Different surgical techniques to establish the rotation of the components can be used, the most common are: anatomical resection (MR), the use of force sensors for balancing spaces (FS_STB) and computer-assisted or navigated technique (CAS_GB). It is controversial whether any surgical technique is superior to another when establishing rotational alignment or which rotational alignment is the most appropriate. This study is divided into two parts. The first part analyzes 9 measurement techniques in 2D-CT to determine the rotation of the femoral and tibial components and of the ATR as a whole. 27 patients were studied, and 9 rotation angles were studied, two measurements of each angle, by three independent observers were done to calculate the intra and inter observer variability, in addition to analyzing the relationship with the clinical results. The second part is a prospective, randomized study that included 60 patients distributed in three groups according to the surgical technique analyzed: MR, CAS_GB and FS_STB. 3 measurements were made in 2D-CT: femoral rotation (BFA) and knee rotation (TE_PTCA and BC_PTCA). It was analyzed which surgical technique best reproduces the native knee rotation and the clinical result (KSS and WOMAAC) and which surgical technique provides better clinical results. In the first study, the results show that for the femoral component the most reproducible technique is that described by Berger in 1993, for the tibial component it is the technique of the anatomical tibial angle (ATA). Regarding the rotation of the ATR, the most reproducible technique is the BC_PTCA and the TE_PTCA which relates the posterior bicondylar axis and the transepicondyle axis with the posterior margin of the tibial plate. The BC_PTCA angle is significantly related to the clinical outcome according to KSS. In the second study, it was observed that the three surgical techniques did not have differences in preoperative rotation and reproduced the native BFA. The FS_STB technique and the CAS_GB reproduce the TE_PTCA and the FS_STB reproduce the BC_PTCA. Likewise, the KSS_FUNCTIONAL was significantly better in the FS_STB technique compared to the other two. In conclusion, our results confirm that in the measurement by 2D-CT the femoral rotation angle (BFA) was the most reproducible and that the tibial angles are not very reproducible with the exception of the ATA. The angles of rotation of the knee have good reproducibility and correlate well with the clinic. The use of a force sensor makes it possible to reproduce the native rotation of the knee (TE_PTCA and BC_PTCA) and achieve significantly better clinical results (KSS) than the other surgical techniques studied (MR and CAS_GB).
Universitat Autònoma de Barcelona. Programa de Doctorat en Cirurgia i Ciències Morfològiques
Kuldavletova, Olga. "L'intégration multisensorielle fonctionnelle et la plasticité des réflexes vestibulaires Vestibulo-sympathetic Reflex in Patients With Bilateral Vestibular Loss Influence of Graviceptor Stimulation Initiated by Off-Vertical Axis Rotation on Ventilation Effect of self-motion perception on autonomic control Vestibulo-Ocular Responses, Visual Field Dependence, and Motion Sickness in Aerobatic Pilots". Thesis, Normandie, 2020. http://www.theses.fr/2020NORMC405.
Texto completoThe aim of this thesis was to specify the role of the vestibular system in the orientation-related homeostasis. We evaluated vestibular responses to changes in orientation in space (1) in normal population to reveal in what proportion different sensory systems are implicated in the generation of the cardio-vascular and respiratory responses, and (2) in populations with altered vestibular afference: bilateral vestibular loss patients and aerobatic pilots.The results indicated that the vestibular system cooperates with trunk graviceptors to evoke respiratory response to changes in orientation during Off-Vertical Axis Rotation protocol (OVAR). The contribution of each sensory source was found to vary between individuals. Another study tested the hypothesis that the vestibular modulation of cardio-vascular parameters can be influenced by visual input during OVAR. Preliminary results from this study have demonstrated that the OVAR stimulation has an effect on the mean cardio-vascular parameters. The modulatory effect of OVAR on the arterial pressure has also been shown. The phases of modulation were varying between individuals which can indicate the neural nature of the observed modulation. The effect of visual stimulation on modulation has been detected, however further analysis is required. In another study, subjects presenting bilateral vestibular loss were shown to have the same cardio-vascular response to changes in the position of the head during Head-Down-Neck-Flexion protocol (HDNF) as normals. This reconstruction of the vestibulo-sympathetic reflex in human seems to originate from the sensory sources other than labyrinthine. Finally, we studied aerobatic pilots as humans experiencing intense and unusual vestibular stimulations. We have not revealed the expected vestibular habituation in the study using the OVAR and EVAR (Earth-Vertical Axis Rotation) stimulations, but were significantly less susceptible to motion sickness. We suggest that the pilots do not develop habituation, as they require unsuppressed responses for a better performance.We conclude that to generate the orientation-related responses, the Central Nervous System integrates the vestibular and non-vestibular signals and is subject to plastic changes in altered sensory conditions, if the response needs to be changed or restored. This multisensory processing is individually tuned, with the variable portion of vestibular impact in this processing, depending on activities, sensory state and the requirements to the response
Alentorn, Puigcerver Jaume. "Estudio de la precisión del método de los componentes para la predicción del comportamiento rotacional de una basa de pilar : propuestas de mejora para el caso de estudio". Doctoral thesis, Universitat Politècnica de Catalunya, 2016. http://hdl.handle.net/10803/383526.
Texto completoLes unions entre els diversos elements estructurals, malgrat que sovint han estat menystingudes a nivell estructural i s'han considerat com a simples detalls constructius, són claus per garantir la correcta distribució d'esforços i assegurar una avinença entre model utilitzat pel càlcul i realitat construïda. Al llarg dels anys s'han dissenyat exclusivament sota el criteri de resistència aspecte que, arrel de la introducció de les noves normatives tals com l'Eurocodi, actualment es pot complementar amb el de rigidesa i, encara en una fase inicial de desenvolupament, amb el de capacitat de rotació o ductilitat. El present treball aprofundeix en un tipus d'unió determinat: les bases de pilars. A part de resumir tot el marc teòric del mètode dels components, que és el mètode predictiu de l'Eurocodi, aquest és aplicat també a nivell practic en un exemple concret de basa de pilar, arribant a obtenir els grafics que la norma preveu pel seu comportament M-0. Aquests es comparen amb els reals, extrets d'una modelització informàtica amb elements finits convenientment calibrada i testejada, per tal de coneixer la precisió que la predicció del metode ofert per la normativa posseeix. En base a aquesta comparació s'estudia la relació existent entre la precisió del comportament M-0 de la unió obtinguda per l'exemple treballat i el valor del ratio de rigidesa (µ) utilitzat. La tesi desenvolupa una nova formulació pel valor del rati de rigidesa que l'acosta més al real, expressions que quan s'incorporen a les del mètode dels components tan augmentar lleument, amb caracter general, la precisió de la predicció del comportament rotacional obtingut per la basa del pilar. Finalment, i a tenor de la millora modesta que provoca incidir únicament en el valor del rati de rigidesa, la tesi desenvolupa una formulació per la variació unitaria de la rigidesa (y) que modifica el traçat del gràfic M-0 de la predicció i l'acosta indefectiblement al real, aconseguint una precisió gairebé absoluta en el cas d'estudi. La principal línia futura d'investigació que es proposa és seguir amb el mètode de treball ideal en aquesta tesi, amb diferents configuracions geomètriques i materials de bases de pilars.Treballant els resultats extrets l'objectiu és aconseguir una formulació de caràcter general, vàlida per qualsevol configuració de basa de pilar que es tingui, que permeti millorar la predicció del seu comportament rotacional. Un cop aconseguides aproximacions més fiables, l'últim pas a per aquesta línia de treball, i el més important a nivell pràctic i professional, és l'invers, és a dir, a partir d'un determinat comportament rotacional desitjat pel dissenyador, oferir diverses configuracions de bases de pilars possibles.
Lázaro, Fernández Carlos Manuel. "Formulación material y espacial del modelo geometricamente exacto de piezas alargadas". Doctoral thesis, Universitat Politècnica de València, 2008. http://hdl.handle.net/10251/1872.
Texto completoLázaro Fernández, CM. (2005). Formulación material y espacial del modelo geometricamente exacto de piezas alargadas [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/1872
Palancia
Κόντος, Αναστάσιος. "Υπολογισμός απωλειών ασύγχρονης μηχανής τροφοδοτούμενης μέσω αντιστροφέα τάσης ελεγχόμενου με τεχνική PWM". Thesis, 2012. http://hdl.handle.net/10889/5593.
Texto completoIn electrical machines the calculation of loss and the mechanisms that cause them are a very demanding subject of study. Recently, the increasing need for ever more efficient machines has made the research focus on the calculation of their losses and more specifically the calculation of the iron losses. The iron losses or core losses, constitute an important part of the total machine losses, but also their calculation is particularly difficult. In this thesis we focus on the calculation of these losses in an asynchronous machine using various methods. More specifically, the first chapter is an introduction to the properties of ferromagnetic materials. First, we study the phenomenon of magnetization and saturation and then we examine the phenomenon of hysteresis and its properties which play a crucial role in the core losses of the machine. Finally we study eddy current phenomenon. In the second chapter we discuss the losses of the machine. In which way the phenomenon of hysteresis and eddy currents generate losses in the machine and the form in which they appear. Also presented are the mechanisms associated with the copper losses, skin effect and proximity effect. Also shown is a literature survey on various methods used to calculate the iron losses. The third chapter is essentially an introduction to power electronics, and more particularly to the PWM technique. Important in this chapter is the way in which the input voltage to the machine affects the iron losses. In the fourth and final chapter we produce results of the above theory using simulation methods. The work is done using a finite element model in two dimensions of a squirrel cage asynchronous machine. Initially the machine is fed by a sinusoidal input voltage. Firstly copper losses are calculated and then the iron losses with the help of computational methods which analyze the magnetic induction in Fourier series. Finally, we study the shape of the magnetic field in different parts of the machine and the losses occurring in each element of the model in each case. These additional losses are known as rotational core losses. These steps are repeated, this time powering the machine via inverter supply using the PWM technique.
(8108663), Mitchell J. Greve. "Edge-of-field Associated Nitrate-N Loss in a Soybean-corn Rotation". Thesis, 2019.
Buscar texto completoAcross the United States corn-belt region substantial quantities of nitrogen (N) fertilizer are applied in both continuous corn (Zea maysL.) and corn grown in rotation with soybean [Glycine max(L.) Merr.]. When compared to continuous corn, corn grown in rotation with soybean typically receives less applied N fertilizer (typically 20-45 kg ha-1less) than continuous corn due to expected carryover of N from biological N fixation (BNF) by soybean in the preceding year. However, when current N recommendations are followed in both systems, rotational corn has been shown to lose similar or, in some cases, greater amounts of N through subsurface tile lines than continuous corn although the reports in the literature have been inconsistent. In rain-fed systems a key limitation to many previous studies has been an insufficient number of site-years of data to fully characterize management effects across varied environments. Regardless, the development of better management practices to reduce nitrate leaching losses has largely remained focused on managing N applied to corn and soybean’s role in degradation of surface water has been relatively understudied in tile drained agroecosystems. Therefore, the objectives of this study were to use a 23-yr data record to: (1) compare quantities and patterns of N loss in tile drainage water among a soybean-corn rotation fertilized with the recommended preplant N rate, a soybean-corn rotation fertilized with a N reduced rate applied as a sidedress, continuous corn fertilized with the recommended preplant N rate, and an unfertilized, restored prairie as a natural system control, (2) determine whether and when cumulative soybean-corn load losses in drainage water surpassed that of continuous corn, and (3) evaluate the current recommended N credits from the dual perspective of crop productivity and protection of water quality.
Established in 1992, the Purdue University Water Quality Field Station has continuously assessed field-scale N cycling and losses in tile drains and the N management of the five treatments examined in this study have been maintained since 1995. Treatments were 135 kg N ha-1 applied in rotational corn as a sidedress at approximately V6 each year (CS-135), 157 kg N ha-1applied preplant in rotational corn (CS-157), and 180 kg N ha-1applied preplant in continuous corn (CC-180). All corn plots received 23 kg N ha-1as starter at planting. A restored perennial prairie control with no fertilizer applied (Pgrass) was utilized to compare and discuss the implications of intensively fertilized annual row crops. The 23-yr data record includes N concentration in drainage water, drainflow volume, N load losses in drainflow, grain yield, tissue N concentrations at harvest and N amounts returned to soil in crop residues and removed in grain.
Analysis of variance found CS-157 resulted in significantly greater daily flow-proportional N concentrations (23-year mean 11.98 mg L-1) when compared to all other cropping systems (≤ 10.96 mg L-1). No reportable significant differences occurred in mean annual drainage flow volume among the respective cropping systems. Annual N load loss was statistically similar among cropping systems, ranging between 9.88 to 12.32 kg N ha-1yr-1, and these were all significantly higher than the Pgrass control (1.70 kg N ha-1yr-1). When corn and soybean years in rotational systems were analyzed separately for leaching losses, CS-157 was significantly higher than CS-135 and CC-180 (14.70, 10.85 and 11.88 kg N ha-1, respectively) whereas losses by SC-157 and SC-135 were similar averaging 12.26 and 12.13 kg N ha-1, respectively. Nitrogen treatment did not impact either corn or soybean mean yields. We concluded that soybean BNF production may be a major driver in N load loss in rotational corn when compared to continuous corn and further reductions in load losses from rotational systems will require a focus on managing soybean-derived N. Lastly, future research should include monthly or seasonal assessment of N load losses to better target practices at vulnerable times of nutrient loss.Wietzke, Alexander. "Arable plant diversity in conventionally managed farmland of Northwest Germany - Current state and a participative approach to increase farmland biodiversity". Doctoral thesis, 2020. http://hdl.handle.net/21.11130/00-1735-0000-0005-14A8-7.
Texto completoKREBSOVÁ, Lenka. "Uplatnění meziplodin jako stabilizujícího prvku v protierozní ochraně". Master's thesis, 2014. http://www.nusl.cz/ntk/nusl-174233.
Texto completoMazzalay, Ximena. "Los pársecs más internos de las galaxias activas /". Doctoral thesis, 2010. http://hdl.handle.net/11086/147.
Texto completoLos núcleos activos de galaxias o AGNs son considerados los objetos más luminosos del Universo. Estos emiten cantidades importantes de energía a lo largo de todo el espectro electromagnético, la cual es capaz de superar por varios órdenes de magnitud a la liberada por el resto de la galaxia. Se cree que esta energía es producida por material ubicado en un disco de acreción alrededor de un agujero negro supermasivo central. Gran parte de la investigación sobre estos objetos llevada a cabo en las últimas tres décadas está dedicada al entendimiento de la fuente central y sus efectos en el gas que la rodea. Con el objetivo de contribuir a estos estudios, en esta Tesis se analizaron las componentes más internas de galaxias activas cercanas a partir del estudio de la emisión continua y de las líneas coronales. La región donde son emitidas estas últimas es la más cercana a la fuente central que puede ser resuelta con los instrumentos ópticos e infrarrojos actuales y, por lo tanto, proveen información sobre los procesos energéticos que ocurren en el centro de los AGNs.
Galaxias activas -- La región de líneas coronales en AGNs -- Una mirada con el telescopio espacial Hubble -- Una visión 3D de la región de líneas coronales de NGC1068 -- La emisión continua de la galaxia activa Mrk 1239 -- Comentarios finales.
Fil: Mazzalay, Ximena. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física; Argentina.
KUKAČKA, Vladislav. "Uplatnění meziplodin jako stabilizujícího prvku proti erozním splachům". Master's thesis, 2010. http://www.nusl.cz/ntk/nusl-48045.
Texto completoEslami, Mansour. "Effect of foot angle changes on body joints and segments during standing and running = Effet de changement d'angle au pied sur les articulations et les segments lors de l'équilibre debout et de la course". Thèse, 2007. http://hdl.handle.net/1866/15466.
Texto completoNzokou, André. "Résultats des cupules de grand diamètre dans les reprises d’arthroplastie totale de hanche : suivi minimum de deux ans". Thèse, 2013. http://hdl.handle.net/1866/10306.
Texto completoAcetabular implant revision with large bone defects, can be challenging. One of the reconstruction options is a large outer diameter cup or “jumbo cup” (≥62 mm in women and ≥66 mm in men). We hypothesized that cementless jumbo cups is a reliable technique to preserve or reconstruct hip center of rotation. We also evaluated stability at least 2 two years follow up. Fifty-three consecutive non septic loosening acetabular arthroplasty revisions at Hopital Maisonneuve-Rosemont where a cementless jumbo cup was used were assessed. Bone defect was evaluated according to Paprosky classification. Mean implanted component size was 66 mm (62-81) in women and 68 mm (66-75) in men. Cancelous bone chips allograft was used in 34 cases and bulk bone allograft in 14. Immediate postoperative AP view showed a mean abduction cup angle of 41.3° (26.0-53.0). Hip centre were found at satisfy position in 78% on mediolateral axis, in 71% on craniopodal axis and it was improved in 27% in this late axis. At the mean follow up of 84.0 months (24.0-236.4) radiologically and 91.8 months (24.0-241.8) clinically: 6 patients were died and 3 were lost of follow up. Complications were: dislocation in 5 cases (4 revisions with constrained liner), infection in 4 cases (2 treated conservatively and 2 revised in 2 times procedure) and radiographic loosening in 1 case. Bone graft integration was completed in all except in 3 cases. Clinically, the mean HHS was 82% +/- 17, WOMAC 86 +/- 14, physical SF-12 46 +/- 12 and mentally SF-12 53 +/- 13. Jumbo cups appear as a reliable procedure to manage bone loss in acetabular revision. It allows conservation or improvement of physiologic hip center. Also, cementless fixation promote bone integration. with subsequent cup stabilitity. The complication rate is comparable or may be less than others reconstruction procedures .