In the last years, well-ordered nanoclusters attract a lot of attention, because they are effectively used to enhance the catalytic capability and Curie temperature for ferromagnetism. However, in the conventional case, the nucleation sites will form 2-dimensional islands and then grow into films with increasing coverage. This kind of 2-D islands restricts the function for the further applications. Thus, in this report, we controlled the growth of 3-D Fe nanoclusters by the method of buffer layer assisted growth (BLAG) on Au(111) herringbone reconstruction structure. The method of BLAG was used to control the Fe nanoclusters size from 2 to 6 nm by the amount of Xe buffer layer and Fe deposition. In addition, the Fe nanodots are confined and arranged at the turning points of the Au(111) herringbone by Fe seeds before the BLAG method. They can be used as the nucleation sites to assemble the well-order nanoclusters by BLAG. From the result, the size controlled 3-D Fe nanoclusters self-assemble at special point. The method of ¡§BLAG on nano-patterned template¡¨ will be very helpful to prepare various 3-D nanoclusters with regular spatial arrangement and to control size of them.

Thèse doctorat : Génie Mécanique : Villeurbanne, INSA : 2001. / Titre provenant de l'écran-titre. Bibliogr. p. 303-307.

Thèse de doctorat : Histoire : Metz : 2007. / Thèse soutenue sur ensemble de travaux. Bibliogr. f.443-478. Index des cartes tabl., graph. f.479. Index des noms de personnes f. 483.

Thesis (M. Phil.)--University of Hong Kong, 2001. / Includes bibliographical references (leaves 89-92).

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This thesis presents an examination of the role of co-operatives in the economic development of pre-independent Cyprus and also in the economic reconstruction effort following the war events of 1974. The provision of credit is a key element of the contribution made by the co-operative movement during these two different phases of the island's modern economic history; first agricultural credit and then housing credit. Government involvement is treated as a very important variable in the co-operative function and various types of such involvement are examined in the course of the thesis, ranging from zero to maximum government input. This maximum type relates to a situation where the initiation, financing and control of co-operatives are tightly in the hands of state agents. In this respect various aspects of institutional theory are applied in order to explain empirical findings. Another important variable of the co-operative function relates to political party involvement. Existing beliefs about the ill-effects of politicisation are put to the test using highly sensitive empirical evidence from Cyprus, available to the author only due to his special relationship with the co-operative movement. The effects of such politicisation are also studied in relation to member participation.

In 3-dimensional positron emission tomography (PET), the proportion of the detected photon coincidences arising from scatter can be very high, up to 60%. A standard approach to scatter correction in 3D PET is to estimate the scattered coincidences and subtract them from the list of recorded events. More recently, novel techniques have been proposed in which the information carried by the scattered photons was extracted and directly used in the image reconstruction step. In this work, the algorithms were extended for use in non-TOF 3D PET systems and were qualitatively and quantitatively evaluated. Despite some promising initial outcomes, standard performance metrics of images reconstructed with each technique, representing the quality of images, was shown to be deteriorated under specified conditions. Further work is required to investigate potential benefits of the proposed algorithms for both ideal and clinical conditions.

Due to infrequent and imprecise maintenance inspection in power-line corridors, accidents can be caused by interferences, for instance, surrounding trees. Transmission power-line inspection conventionally relies on the participation of ground personnel and airborne camera to patrol power-lines, and is limited by intensive labour, and difficult working conditions and management. Airborne light detection and ranging (LiDAR) has proven a powerful tool to overcome these limitations to enable more efficient inspection. Active airborne LiDAR systems directly capture the 3D information of power infrastructure and surrounding objects. This study aims at building a semi-automatic 3D reconstruction workflow for power-lines extracted from airborne LiDAR data of 138 kV transmission line corridors (500 m by 340 m) in Nanaimo, BC, Canada. The proposed workflow consists of three components: detection, extraction, and fitting. The power-lines are automatically detected with regular geometric shape using a set of algorithms, including density-based filtering, Hough transform and concatenating algorithm. The complete power-lines are then extracted using a rectangular searching technique. Finally, the 3D power-lines are reconstructed through fitting by a hyperbolic cosine function and least-squares fitting. A case study is carried out to evaluate the proposed workflow for hazard tree detection in the corridor. The results obtained demonstrate that power-lines can be reconstructed in 3D, which are useful in detection of hazard trees to support power-line corridor management.

This thesis present a new algorithm for creating high quality surfaces from large data sets of oriented points, sampled using a laser range scanner. This method works in two phases. In the first phase, using wavelet surface reconstruction method, we calculate a rough estimate of the surface in the form of Haar wavelet coefficients, stored in an Octree. In the second phase, we modify these coefficients to obtain a higher quality surface. We cast this method as a gradient minimization problem in the wavelet domain. We show that the solution to the gradient minimization problem, in the wavelet domain, is a sparse linear system with dimensionality roughly proportional to the surface of the model in question. We introduce a fast inplace method, which uses various properties of Haar wavelets, to solve the linear system and demonstrate the results of the algorithm.