by Lam Ching Chi. / Parallel title in Chinese characters. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1991. / Includes bibliographical references. / List of Table --- p.v / List of Figures --- p.vi / Acknowledgments --- p.xv / Abstract --- p.xvi / Chapter Chapter 1 --- Introduction --- p.1 / Chapter Chapter 2 --- Electromagnetic wave scattering from a homogeneous sphere : Mie scattering --- p.13 / Chapter 2.1 --- Introduction / Chapter 2.2 --- Formulation / Chapter 2.3 --- Morphology-dependent resonance (MDR) / Chapter 2.4 --- Quasinormal modes / Chapter 2.4.1 --- Introduction / Chapter 2.4.2 --- Location of poles of the S-matrix / Chapter 2.4.3 --- Quality factor / Chapter 2.4.4 --- Scattering efficiency / Chapter 2.5 --- The general effect on scattering from a perturbed sphere / Chapter Chapter 3 --- T-matrix method for scalar wave scattering --- p.48 / Chapter 3.1 --- Introduction / Chapter 3.2 --- Formalism for scalar waves / Chapter 3.3 --- Evaluation of matrix element / Chapter 3.4 --- Incident wave expansion coefficients / Chapter 3.5 --- Scattering efficiency / Chapter 3.6 --- An application of the T-matrix method / Chapter 3.7 --- Discussions and conclusion / Chapter Chapter 4 --- Logarithmic perturbation method in scattering of scalar waves --- p.77 / Chapter 4.1 --- Introduction / Chapter 4.2 --- Formalism / Chapter 4.2.1 --- Defining relations / Chapter 4.2.2 --- The matrix equation / Chapter 4.3 --- Evaluation of matrix element / Chapter 4.4 --- Scattering features and properties / Chapter 4.4.1 --- Poles of the S-matrix / Chapter (a) --- First order / Chapter (b) --- Second order / Chapter 4.4.2 --- Quality factor / Chapter 4.4.3 --- T-matrix representation / Chapter 4.5 --- Degenerate perturbation / Chapter (a) --- Weak coupling limit / Chapter (b) --- Stong coupling limit / Chapter Chapter 5 --- Study of wave scattering from slightly deformed spheres using logarithmic perturbation method --- p.110 / Chapter 5.1 --- Introduction / Chapter 5.2 --- Results and Discussions / Chapter 5.2.1 --- Evaluation of matrix element / Chapter 5.2.2 --- Scattering efficiency / Chapter 5.2.3 --- Frequency shift / Chapter 5.2.4 --- Quality factor / Chapter 5.2.5 --- Physical interpretation for quadrupole distortions / Chapter Chapter 6 --- Morphology-dependent resonances in radially-inhomogeneous spheres --- p.143 / Chapter 6.1 --- Introduction / Chapter 6.2 --- Formalism / Chapter 6.3 --- Numerical method / Chapter 6.4 --- Logarithmic perturbation method / Chapter 6.5 --- Scattering properties / Chapter 6.5.1 --- Pole shift / Chapter 6.5.2 --- Quality Factor / Chapter 6.6 --- A specific example : Results and Discussions / Chapter Chapter 7 --- Conclusion --- p.165 / Appendix A --- p.168 / Appendix B --- p.170 / Appendix C --- p.171 / Appendix D --- p.175 / Appendix E --- p.178 / Appendix F --- p.181 / Appendix G --- p.183 / Appendix H --- p.186 / Appendix I --- p.192 / References --- p.195

在這篇畢業論文里，我們將闡述微分球面定理。這是由Brelldle和孫理察在2007年用里奇流所證明的。球面定理的研究在微分幾何中有很長的歷史。人們研究一種稱為δ-pillched的截面曲率條件(δ在0和1 之間) ，使得一個緊致單連通的黎曼流形滿足這個曲率條件就會同胚或者微分同胚于一個球面。里奇流是由哈密爾頓在1982年所引進的，當時，他證明了任意一個閉單連通三維黎曼流形只要滿足正的里奇曲率條件就微分同胚于一個球面。 / 在這里，我們會闡述關於里奇流的一些基本結果，包括曲率在里奇流下變化的方式、短時間存在性、唯一性以及曲率和一般張量的高階導數估計。同時，我們也會講述一般的在里奇流下的極大值原理以及收斂性定理。非負迷向曲率條件能夠在里奇流下得到保持的結果也會被詳細證明。最後，我們通過由Böhm 和Wilkillg斤引進的一簇不變圓錐來完成整個微分球面定涅的證明。 / In this thesis, we present the proof of the differentiable sphere theorem which was proved by Brendle and Schoen in 2007 using the Ricci flow. The sphere theorem in differential geometry has a long history. People studied the δ-pinched sectional curvature condition showing that for various cases of δ ∈ (0, 1), any simply-connected, compact Riemannian manifold with this curvature condition is homeomorphic or diffeomorphic to a sphere. The Ricci flow was introduced by Hamilton in his seminal paper in 1982 which proved that every simply-connected, compact three-manifold with positive Ricci curvature is diffeomorphic to a sphere. / In this text, we present some background materials for the Ricci flow, including curvature evolution under the Ricci flow, short-time existence, uniqueness and higher derivatives estimate for curvature and tensor. We also focus on the maximum principle and convergence criterion for the Ricci flow. The fact thatnonnegative isotropic curvature is preserved under the Ricci flow will be showed.Finally, we complete the proof of the differentiable sphere theorem using a family of invariant cones which was constructed by Böhm and Wilking. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Huang, Shaochuang. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2013. / Includes bibliographical references (leaves 96-98). / Abstracts also in Chinese. / Abstract --- p.i / Acknowledgements --- p.iii / Chapter 1 --- Introduction --- p.1 / Chapter 2 --- Background Materials for The Ricci Flow --- p.6 / Chapter 2.1 --- Evolution of curvature under the Ricci flow --- p.6 / Chapter 2.2 --- Short-time existence --- p.13 / Chapter 2.2.1 --- The Ricci tensor is not elliptic --- p.13 / Chapter 2.2.2 --- DeTurck’s trick --- p.17 / Chapter 2.3 --- Uniqueness --- p.20 / Chapter 2.4 --- Estimates for derivatives of curvature --- p.22 / Chapter 2.5 --- Estimates for derivatives of tensor --- p.25 / Chapter 3 --- Hamilton’s Maximum Principle for The Ricci Flow --- p.30 / Chapter 4 --- Hamilton’s Convergence Criterion for The Ricci Flow --- p.39 / Chapter 5 --- Nonnegative Isotropic Curvature --- p.54 / Chapter 5.1 --- Nonnegative isotropic curvature is preserved --- p.54 / Chapter 5.2 --- The Cone Ĉ --- p.67 / Chapter 6 --- Proof of The Differentiable Sphere Theorem --- p.73 / Chapter 6.1 --- An algebraic identity for curvature tensors --- p.73 / Chapter 6.2 --- Construction of a family of invariant cones --- p.80 / Chapter 6.3 --- Proof of The Differentiable Sphere Theorem --- p.87 / Bibliography --- p.96

Les critères d’accès à la citoyenneté « moderne » qui ont été élaborés pour les colonisé·e·s après la seconde guerre mondiale, comportent dès le départ une forte dimension genrée. Bien que ces normes voient le jour dans un contexte réputé pour son ouverture à une relative libéralisation de la vie sociale et politique, les restrictions qu’elles comportent et les mécanismes de leur mise en œuvre mettent à jour le souhait des autorités coloniales de contrôler un changement devenu inévitable. Elles instituent alors une sphère publique dans laquelle, elles sont garantes de la légitimité des interlocuteurs.trices qui y officient. Les soubassements disqualifiant qui régissent la participation politique moderne à l’origine, ont eu un effet durable sur la manière dont ce processus est investi par les autorités, les populations et l’historiographie. Ainsi, dans le cas du Cameroun, la construction genrée de la citoyenneté abouti d’une part, à une présence marginale des femmes au sein des instances politiques – et dans l’espace politique conventionnel, de manière générale – et, d’autre part, à leur sous-representation dans l’historiographie politique du Cameroun. Pour autant, cette sous-représentation des femmes dans l’histoire et la vie politique ne traduit pas une participation politique négligeable, mais, plutôt, une visibilité différenciée des hommes et des femmes dans la sphère publique. Ce travail vise alors à démontrer que des Camerounaises manifestent constamment la volonté de s’imposer comme agentes politiques. Dans une approche qui étend le périmètre de la participation politique à des modes d’action ne relevant pas uniquement de la modernité occidentale, cette recherche éclaire les actions politiques plurielles (collectives ou individuelles) de ces femmes. / Since the beginning, the access requirements to the “modern citizenship” developed for colonized people after the Second World War have a strong gendered dimension within their configuration. Although theses norms and regulations are emerging in a context renowned for its opening to a relative liberalization of social and political life, the limitations they contain plus the mechanisms of their implementation shed some light on the desire of the colonial authorities to seriously consider the inevitable change. They then set up a public sphere in which they guarantee the legitimacy of the interlocutors presiding there. The disqualifying underpinnings of the modern political participation have had a lasting effect on how the whole process is invested by authorities, populations and historiography. Thus, in the case of Cameroon, the gendered construction of citizenship lead to a marginal presence of women in political bodies – and more precisely in the formal political field –, as well as in the country’s political historiography. However, this underrepresentation within political space and history does not mean that women involvement in politics is insignificant. It reflects, rather, a visible distinction of men and women in the public sphere. So, this work aims to prove that Cameroonian women stand out as political agents on a constant basis. By extending the perimeter of political participation to actions, not being only derived from Western modernity, this research reveals the varied political actions (collective or individual) taken by these women

The primary focus of this work is to develop an understanding of crystallisation in hard sphere systems. The thesis is presented in two parts. The first section is an investigation of the liquid/crystal interface at equilibrium using molecular dynamical simulations. The objective is to understand how the interface might bridge between the disordered and ordered states in liquid/crystal environments. Topological measures of structure are used to investigate whether any precursor structures are present in the liquid phase, close to the interface, that would allow transition from disorder to order. This differs from other work where simpler measures of structure, classifying phases into either liquid or crystal, are used. The results indicate that the liquid/crystal interface of a hard sphere system is very narrow and no readily observable structures were found that extended past the width of the equilibrium interface. The second section of the thesis is a theoretical study of growth kinetics in hard sphere systems using density functional theory. The kinetics in a fixed volume are examined with a single conserved order parameter. The work is extended incorporating both conserved particle and non-conserved structure dynamics. The kinetics of growth are examined and it is shown that the small initial crystals are quickly isolated from the higher pressure of the surrounding system through the development of a depletion zone.

The city of Valparaiso is an incredibly complex city with multiple actors each with a different cultural agenda. Compounded by the unclear laws and politics surrounding the 2003 UNESCO world heritage designation, it is an urban center brimming with tension. Within this space, graffiti articulates an unmediated, anti-hegemonic voice within the public sphere. The tactics and strategies used to disseminate this cultural expression have allowed graffiti to find a tenuous, if ever present existence in the city. Paradoxically, as the individual authors tactically and strategically align to produce a forceful graffiti movement, they have also put themselves and their graffiti in a position where it can be usurped and used for the purposes of promoting Valparaiso as a hip, bohemian site of authentic, consumable culture. Graffiti can be read as a written signal of disaccord, yet its move into the codified gallery spaces of Chilean government re-inscribe graffiti within a historical cannon determined by cultural and government authorities. By exploring graffiti in São Paulo as a parallel to graffiti in Valparaiso and the Expo Graffiti Porteño, I problematize the practice of delineating graffiti into categories of art verses vandalism. This division is polemical and divisive and obscures the significance of all and any graffiti within the public sphere. Ultimately, this project seeks to examine graffiti’s marginal position and the consequences of its acceptance by institutions that confer artistic or cultural legitimacy. / text

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The structure of a polymeric material has a great influence in many fundamental scientific areas as well as in more applied science, since it affects the diffusion, permeability, mechanical strength, elasticity, and colloidal properties of the materials. The results in this thesis demonstrate that it is possible to fabricate solid and hollow cellulose spheres with a cellulose shell and encapsulated gas, liquid or solid particles and with a sphere size ranging from a few hundreds of nanometres to several millimetres, all with a tailored design and purpose. The sizes of the different spheres have been controlled by three different preparation methods: large cellulose macrospheres by a solution solidification procedure, hollow micrometre-sized cellulose spheres by a liquid flow-focusing technique in microchannels, and nanometre-sized cellulose spheres by a membrane emulsification technique.  The spheres were then modified in different ways in order to functionalize them into more advanced materials. This thesis demonstrates how to control the cellulose sphere dimensions and the wall-to-void volume ratio, the elasticity and the functionality of the spheres as such, where they were prepared to be pH-responsive, surface specific and X-ray active. These modifications are interesting in several different types of final materials such as packaging materials, drug release devices or advanced in vivo diagnostic applications. In the more fundamental science approach, surface-smooth solid cellulose spheres were prepared for characterization of the macroscopic work of adhesion when a cellulose surface is separated from another material. Using these ultra-smooth macroscopic cellulose probes, it is possible to measure the compatibility and the surface interactions between cellulose and other materials which provide an important tool for incorporating cellulose into different composite materials. / <p>QC 20140829</p>

Mode of access: World Wide Web. / Thesis (Ph. D.)--University of Hawaii at Manoa, 2004. / Includes bibliographical references (leaves 113-114). / Electronic reproduction. / Also available by subscription via World Wide Web / vii, 114 leaves, bound ill. 29 cm