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This thesis presents a study on the design and analysis of a morphing flap structure integrated with actuation mechanism for potential application to large aircraft. Unlike the conventional rigid flap mounted on the wing trailing edge, the morphing flap is designed as a unitized structural system integrated with three primary components: the upper and lower flexible skins reinforced by stringers, an eccentric beam actuation mechanism (EBAM) with discs fixed on it, and the connection of the discs with the stringers. Based on the EBAM concept proposed by Dr Guo in previous research [1], the current study has been focused on the EBAM design and optimization, kinematic simulation and structural modelling of the morphing flap. Although a lot of efforts have been made to develop the morphing flap in previous research, it is lack of detailed design of the disc-skin linkage and clear view on the mechanism optimization in relation to the shape requirement. The main objective of this research is to meet the morphing shape requirements and calculate the actuation torque for a specified morphing flap. Firstly effort was made to design and optimize the disc shape and locations in the EBAM for the best matching of the specified morphing shape with minimum actuation torque demand. It is found that minimum three discs are required and their locations have little effect on the actuation torque. Secondly attention was focused on designs of the disc and a C-linkage with the stringers. To ensure that the C- linkage works in practice, a twisted stringer flange design was proposed. Thirdly the actuation mechanism was integrated with the stiffened skin to play the role of an active rib in the flap structure. Based on the design, FE modelling and analysis of the morphing flap structure was carried out. The behaviour of the morphing flap under the internal actuation and external aerodynamic load was applied for stress analysis and detailed design of the structures. Finally the kinematics of the integrated morphing flap was simulated by using CATIA to demonstrate the feasibility and the effectiveness of the improved design.

Il est actuellement bien connu que les molécules non sphériques peuvent former des mésophases (ou cristaux liquides), c'est-à-dire des phases dont les propriétés sont intermédiaires entre celles des liquides et celles des cristaux. La mésophase la plus connue est la phase nématique. Il s'agit d'une phase caractérisée par une distribution aléatoire des centres de masse des molécules, mais dans laquelle l'orientation des molécules présente une direction préférentielle, désignée par un vecteur unité appelé le directeur du nématique. Une telle phase possède donc la fluidité d'un liquide tout en présentant, tel un cristal, une biréfringence. C'est cette dernière propriété qui est exploitée dans les applications technologiques, principalement dans les dispositifs d'affichage. Dans un tel dispositif, le liquide nématique est contenu dans une cellule (il y a une cellule par pixel), et son directeur est manipulé à l'aide d'un champ extérieur, électrique ou magnétique. Pour une bonne compréhension du fonctionnement de ce dispositif, il est essentiel de connaître le profil du directeur à travers la cellule en l'absence de champ extérieur. Dans le cadre de ce travail, nous avons étudié un nématique torsadé, c'est-à-dire dont le directeur décrit une hélice à travers la cellule. Ce profil est déterminé principalement par les propriétés d'ancrage du liquide nématique sur les parois solides de la cellule. En effet, celles-ci peuvent posséder une direction d'ancrage privilégiée, qui favorise l'alignement du directeur dans une direction particulière. Nous avons considéré ici le cas de directions d'ancrage planaires, c'est-à-dire que le directeur est dans le plan des parois. Alors que l'ajout de parois identiques dans le système induit toujours une non-uniformité spatiale dans la densité du nématique (en comparaison avec un nématique en coeur de phase), l'utilisation de directions d'ancrage différentes induit une non-uniformité orientationnelle dans le directeur du nématique; dans notre cas une torsion. C'est principalement ce profil de directeur torsadé qui nous intéresse ici. L'objectif général de ce travail consiste donc à étudier les propriétés d'ancrage d'une phase nématique confinée et torsadée, d'une part par une théorie microscopique (théorie de la fonctionnelle de la densité), et d'autre part sur le plan de simulations de Monte Carlo, en particulier dans le cas où les molécules ont la forme de disques (discotiques).

Around 1990, Arthur proved a local (ordinary) trace formula for real or p-adic connected reductive groups. The local trace formula is a powerful tool in the local harmonic analysis of reductive groups. One of the aims of this thesis is to establish a local twisted trace formula for certain non-connected reductive groups, which is a twisted version of Arthur’s local trace formula. As an application of the local twisted trace formula, we will prove some twisted orthogonality relations, which are generalizations of Arthur’s results about orthogonality relations for tempered elliptic characters. To establish these relations, we will also give a classification of twisted elliptic representations.

Around 1990, Arthur proved a local (ordinary) trace formula for real or p-adic connected reductive groups. The local trace formula is a powerful tool in the local harmonic analysis of reductive groups. One of the aims of this thesis is to establish a local twisted trace formula for certain non-connected reductive groups, which is a twisted version of Arthur’s local trace formula. As an application of the local twisted trace formula, we will prove some twisted orthogonality relations, which are generalizations of Arthur’s results about orthogonality relations for tempered elliptic characters. To establish these relations, we will also give a classification of twisted elliptic representations.

Invariants of knots coming from twisted signatures have played a central role in the study of knot concordance. Unfortunately, except in the simplest of cases, these signature invariants have proven exceedingly difficult to compute. As a consequence, many knots which presumably can be detected by these invariants are not a well understood as they should be. We study a family of signature invariants of knots and show that they provide concordance information. Significantly, we provide a tractable means for computing these signatures. Once armed with these tools we use them first to study the knot concordance group generated by the twist knots which are of order 2 in the algebraic concordance group. With our computational tools we can show that with only finitely many exceptions, they form a linearly independent set in the concordance group. We go on to study a procedure given by Cochran-Harvey-Leidy which produces infinite rank subgroups of the knot concordance group which, in some sense are extremely subtle and difficult to detect. The construction they give has an inherent ambiguity due to the difficulty of computing some signature invariants. This ambiguity prevents their construction from yielding an actual linearly independent set. Using the tools we develop we make progress to removing this ambiguity from their procedure.

Twenty-odd years ago, scientists managed to produce several new techniques for manipulating certain properties of laser and microwave radiation. These new properties made it possible for the radiation to contain a lot more information than what was previously known. What they had discovered was that light could be twisted, thereby not only carrying polarization, also known as spin angular momentum (SAM) but also orbital angular momentum (OAM).Radar beams are used by scientists to probe the earth’s ionosphere. By measuring the echo of the radar waves one can deduce a lot of information, such as density and temperature of the plasma. In this thesis we will expand an existing program (iscatspb0.m) which computes the spectrum of plasma fluctuations as seen with an incoherent scatter radar, to having it incorporate radar beams carrying OAM, to see what new information of the plasma can be obtained.The three major findings in this thesis were what magnitude of the integer l is needed in order for the contribution of OAM to equal the contribution for the beam opening angle, how much the radar beam opening angle affected the measurements and in what way the spectrum obtained by a twisted beam is affected by different flows

Twisted pan (structured wire) cabling is a principal component in the communications infrastructure, with millions of meters being installed weekly. The rate of increase in upper frequency for this cable appears to be doubling approximately every two years. Clearly, a rigorous approach to the design of these cables is fundamental to achieving data transmission at these frequencies with increasingly stringent performance requirements. This thesis derives a family of equations for the secondary parameters based on an explicit relationship between cable dimensions and materials. These equations have been validated against experimental results and fOWld accurate. Further. equations are developed which calculate the overall S-parameters for cascaded multi.pair cables, the return loss and cross-talk between transmission charmels. In tenns of cable specification. the secondary parameters are the most significant with many of the perfonnance criteria based on these. With designs based largely on the manipulation of physical dimensions, there has been no family of secondary parameter equations given explicitly as functions of cable dimensions and material properties. Similarly, tools have not existed to allow the investigation of design variability or the effects of handling and installation. These are principal requirements in the cable design process. A modelling package, based on Transmission-Line Matrix (TLM) modelling, is developed to a1low the investigation of manufacturing variability and installation handling effects on overall perfonnance of a cable. This modelling technique is validated against both experimental results and analytical results the comparison is excellent. Finally a novel method for the calculation of cross talk between cable pairs is presented. This method is based on a hybrid field·circuit model. Comparisons with measurements show good agreement.

An experimental study is presented on the non-linear twisting of plates with free edges, through the application of self-equilibrating corner loads. A simple apparatus was designed and various sizes of plates were twisted while measuring the surface strains on both sides at the centre. Initial difficulty was encountered due to unwanted deflection of the plate under its own weight. The Rayleigh-Ritz method is used to determine an analytical relationship between midsurface strains and curvatures in the pre- and post-bifurcation regions of twisting. In both the experimental and analytical results, the midsurface strains are found to vary linearly with the Gaussian curvature. Non-dimensional groups are identified which collapse the experimental load-strain, load-curvature and midsurface strain-Gaussian curvature relationships. These non-dimensional groups collapse the results in both the linear and non-linear regions. The curvature at the point of bifurcation is identified as a function of plate dimensional parameters. Also shown are the expressions for critical surface strain and corner load at which bifurcation occurs. The experimental load-curvature relationship and point of bifurcation are compared with analytical results found in the literature. A large discrepancy in the literature is resolved for the theoretical point of bifurcation. The present results form a basis for verification of future analytical results, and are important in the measurement of constitutive relationships using the twisted plate test. / Applied Science, Faculty of / Mechanical Engineering, Department of / Graduate

京都大学 / 0048 / 新制・論文博士 / 博士(医学) / 乙第13234号 / 論医博第2174号 / 新制||医||1036(附属図書館) / 京都大学大学院医学研究科内科系専攻 / (主査)教授 長船 健二, 教授 瀬原 淳子, 教授 小川 修 / 学位規則第4条第2項該当 / Doctor of Medical Science / Kyoto University / DFAM