La medida de parámetros dinámicos de objetos en movimiento es importante en diversas actividades tales como el entrenamiento de deportes, la balística o la aeronáutica. Los parámetros básicos requeridos en estas aplicaciones son la velocidad, la trayectoria y la velocidad de rotación. Esta última es importante puesto que algunos de los principales efectos aerodinámicos que se producen dependen de su existencia. Para la medida de estos parámetros se usan técnicas muy diferentes. Los coeficientes aerodinámicos suelen obtenerse con la ayuda de túneles de viento para medir las fuerzas que aparecen sobre el objeto mientras que la velocidad y la rotación son obtenidos principalmente mediante técnicas basadas en el procesado de la imagen. El uso de túneles de viento suele ser complicado y costoso mientras que las técnicas de procesado de imagen, si bien proporcionan buenos resultados en las medidas, presentan una serie de inconvenientes y condiciones de uso que limitan su aplicación. Además, si bien la medida de la velocidad de rotación es interesante debido a que este parámetro es el causante de una serie de efectos aerodinámicos que modifican la trayectoria, son los coeficientes aerodinámicos los que realmente permiten reconstruir toda la trayectoria del objeto. El objetivo del presente trabajo es el desarrollo y la construcción de un dispositivo que permita la determinación de los coeficientes aerodinámicos de objetos esféricos en movimiento mediante un procedimiento alternativo al tratamiento de imagen o uso de túneles de viento. Este procedimiento se basa en la medida de las variaciones de velocidad que sufre el objeto debido a la presencia de las fuerzas que intervienen en el movimiento. La medida de la velocidad se realiza mediante el uso de barreras ópticas de gran área de medida, para lo cual también se ha desarrollado un procedimiento para medir las tres componentes de la velocidad instantánea usando estos dispositivos. Una vez conocidos los coeficientes los demás parámetros pueden derivarse de estos. Se han realizado pruebas usando balones deportivos, puesto que es una de las áreas de aplicación más directa y facilita el desarrollo de un prototipo. / Lluna Gil, E. (2011). Sistema electro-óptico para la medida de los coeficientes aerodinámicos de objetos esféricos en movimiento [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/11236 / Palancia

A wing was designed with a moving surface high-lift device in the form of a rotating cylinder at the leading edge to improve low speed flight characteristics. This rotating cylinder accelerates the air flow over the top of the wing, effectively combining the concept of lift generated by an airfoil and lift generated by a rotating cylinder. This faster moving air over the top of the wing increases the pressure differential, thus increasing lift. The added momentum to the air flow results in delayed flow separation and a decrease in drag. For experimental testing, a wing was built using balsawood, basswood and MonoKote and was tested in a subsonic wind tunnel using two different tests stands. For validation and further testing, the high-lift device was modeled in Gambit and numerical simulations were performed using ANSYS Fluent. Experimental and numerical data show the high-lift device to be effective.

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The computation of Schrödinger equations in the semiclassical regime presents several enduring challenges due to the presence of the small semiclassical parameter. Standard approaches for solving these equations commence with spatial discretisation followed by exponentiation of the discretised Hamiltonian via exponential splittings. In this thesis we follow an alternative strategy${-}$we develop a new technique, called the symmetric Zassenhaus splitting procedure, which involves directly splitting the exponential of the undiscretised Hamiltonian. This technique allows us to design methods that are highly efficient in the semiclassical regime. Our analysis takes place in the Lie algebra generated by multiplicative operators and polynomials of the differential operator. This Lie algebra is completely characterised by Jordan polynomials in the differential operator, which constitute naturally symmetrised differential operators. Combined with the $\mathbb{Z}_2$-graded structure of this Lie algebra, the symmetry results in skew-Hermiticity of the exponents for Zassenhaus-style splittings, resulting in unitary evolution and numerical stability. The properties of commutator simplification and height reduction in these Lie algebras result in a highly effective form of $\textit{asymptotic splitting:} $exponential splittings where consecutive terms are scaled by increasing powers of the small semiclassical parameter. This leads to high accuracy methods whose costs grow quadratically with higher orders of accuracy. Time-dependent potentials are tackled by developing commutator-free Magnus expansions in our Lie algebra, which are subsequently split using the Zassenhaus algorithm. We present two approaches for developing arbitrarily high-order Magnus--Zassenhaus schemes${-}$one where the integrals are discretised using Gauss--Legendre quadrature at the outset and another where integrals are preserved throughout. These schemes feature high accuracy, allow large time steps, and the quadratic growth of their costs is found to be superior to traditional approaches such as Magnus--Lanczos methods and Yoshida splittings based on traditional Magnus expansions that feature nested commutators of matrices. An analysis of these operatorial splittings and expansions is carried out by characterising the highly oscillatory behaviour of the solution.

In 13th century Europe, the German bishop and scholastic philosopher Albertus Magnus was one of the most influential writers on the natural world and theology. This thesis investigates the relationship between humans and animals in his Quaestiones super de animalibus and De animalibus. In writings on medieval history the theologically enforced boundary between humans and animals is both emphasized and treated as a given. This study nuances the picture presented by previous scholars by highlighting an alternative natural philosophical discourse on humans and animals. Using discourse analysis, I argue that the differences that Albertus used to differentiate humans from animals were based on an understanding of similarities rather than opposites. To Albertus, the human was one species in the animal kingdom, thus sharing many basic functions with other animals. His understandings entailed a theory of essential differences between species but also allowed for divisions based on gradation and relativity. This study sheds new light on the complex relationship between humans and animals in medieval Europe.

Nous étudions expérimentalement différentes figures d'impacts de solides sur des liquides. Dans un premier temps, nous lançons à grande vitesse une bille dans un bain. Nous mesurons sa décélération et en déduisons la force exercée par le fluide sur la bille. Nous montrons ainsi qu'une mousse fortement cisaillée se comporte comme un fluide visqueux. Lors de ces impacts violents, de l'air est entraîné dans le bain par le projectile. Il se forme alors au sein du liquide une cavité que nous caractérisons : elle prend la forme d'un tunnel dans la mousse, d'un vase dans une huile visqueuse, et d'une spirale dans l'eau si la bille tourne sur elle-même au moment de l'impact. Nous nous intéressons ensuite à des impacts à plus faible vitesse, en remplaçant le bain par un film liquide : film de savon ou film visqueux étendu sur un plan. Les forces capillaires deviennent alors comparables à l'inertie des projectiles. On montre alors qu'une bille venant frapper un film peut rester piégée dans le liquide. Une mousse, qui contient de nombreux films liquides, peut ainsi freiner puis capturer des solides par capillarité.

<p>Background: In the eighties the debate concerning the declining relevance of the traditional calculation started. The reason was that the method of calculating not had been changed despite that the costs and manufacturing had changed in many companies. This led to the development of activity-based costing. Management by means of activity information is called activity-based management, but there is no general accepted definition of what the term com- prises. Neither are there any studies which describe within which areas activity information is used as a base for decisions. </p><p>Purpose: The purpose of this thesis is to describe in which situations activity information is used as a base for different decisions, and to define the term activity-based management. </p><p>Method: The approach taken is qualitative. A total of 13 telephone interviews with four different companies, three producers and one wholesale firm, have been carried out. </p><p>Results: Activity information is used as a base for decisions principally in situations that concerns changes in the operational work through management of processes, price and product changes and costumer profitability. Changes within these areas may concern increases in efficiency and effectiveness, and changes in price, assortment and focus on different costumers. In a long perspective these changes may lead to an increase in the profitability. From the studied empirical applications we formulated the following definition of the ABM- term: “The use of activity information as a support for decisions, which concerns securing the companies profitability and to make activities and processes visible and in that way make improvements possible.”</p>

<p>Background: It has been shown that EDI can yield positive effects within companies. Which effects are possible for a company to direct assign to the introduction of EDI and is it possible to estimate the total effect.</p><p>Purpose: The purpose of this study is to estimate and analyze the effects of using EDI in electronic business. We also want to contribute with a model for measure and estimate the effects of EDI.</p><p>Accomplishment: We have studied literature concering EDI and realized a preliminary studie in form of interviews with experts to establish deeper knowledge of EDI. We have also tried to estimate the effects obtained in companies in three different businesses, power, government and transport industry.</p><p>Result: To obtain as good effects as possible it is important that the co- oporation is built on trust and engagement. Before implementing the EDI-system a thorough overhaul of the processes in the company should be done, involving both the top managers and the staff. Internet can be used to achieve minimal cost and it is important to limit the information sent by EDI to only send the information demanded. Finally companies also should mediate the advantages of EDI inside the organisation to make the co-operators realize the good effects obtained by EDI.</p>

<p>Almost everyday we can read about or listen to the radio the creation of a new company, which is of course successfull and just started several months ago. One succeed but for how many other failures. In our everyday life we only know the companies which exist. We never consider all the high number of companies that have failed. In addition to that, by analyzing some cases, we can notice that some"good"companies, with good team, good concept can failed too. In order to understand the views that exist, one needs to elucidate this problem. The early stage of a new-created company is the most important phase of the firm´s life, according to the fact that it will determine the evolution of its whole structure, and therefore will deeply affect its future. All the more so a firm in order to be successful must be able to growth in the long run. With this thesis, we hope to contribute to a better understanding of the key- success factors ofyoung companies. Therefore we will try to clarify issues concerning this early stage. In particular we will highlight and describe that the early development in a firm is a very important phase in its life. And to determine which factors must be take in consideration in order to avoid future difficulties.</p>