Multi-modality imaging is a possible solution for overcoming individual modality limitations. With the use of modality specific contrast agents, contrast-enhanced multi-modality imaging may provide a more comprehensive evaluation of tumour characteristics. This may be possible by combining ultrasound and magnetic resonance imaging, whose contrast agents behave differently within the microvasculature. A novel, microvascular, and leaky phantom is presented that permits ultrasound contrast agents to remain entirely within the mimicking vascular compartment while the magnetic resonance contrast agents may freely diffuse between the mimicking vasculature and tissue compartments. The results show that the phantom is a useful tool for investigating the combination of contrast-enhanced ultrasound and magnetic resonance imaging. This work motivates further combined contrast-enhanced imaging studies, with future work to incorporate additional modalities.

Interferometry and holography are two well-known methods for measuring distances, positions, vibrations, index of refraction etc. In these methods a coherent light source is used to create interference between different parts of the light. Since the wavelength of the light is used as reference it is possible to achieve very good accuracy in the measurements. The need of small and cheap light sources for these applications is large and an interesting alternative would be to use ordinary semiconductor diode lasers. These are unfortunately not designed to give sufficiently good coherence. In this Master Thesis work investigations of how the coherence of semiconductor diode lasers is affected by changes in temperature, injection current and between different individuals are performed. A Michelson interferometer is used to create an interference pattern where the contrast then can be analyzed. The contrast is related to the coherence of the laser, i.e., good coherence will give high contrast. The results show that in order to drive the laser in a stable way it is better to hold the temperature constant and varying the injection current until the wanted output power is achieved instead of doing the opposite. The results also indicate that the best coherence is achieved for low temperatures (around 10 OC) and high injection currents (around 80 mA). During these conditions a contrast of 70 % -80 % is achieved. The result of this Master Thesis work gives a hint on how to run a semiconductor diode laser in a stable way.

Frederic Francois Chopin was the first composer to write a Ballade as an instrumental musical work. From 1831 to 1843 he wrote a total of four Ballades. This study primarily discusses Chopin's use of contrast in the Ballade in G minor, opus 23 and in the Ballade in F minor, opus 52. First, it discusses the background of Chopin's life and his composition of the Ballades. Second, it reviews the origin and development of those genres of poetry and music called "ballad" or "ballade" that relate to Chopin's Ballades. Finally, it focuses on the ways that Chopin utilizes contrast in the G minor Ballade and the F minor Ballade, on whether or not the contrasts appear differently in different musical forms, and on allowing the performer to understand the unique kinds of writing in the Ballades. It is hoped that the performer who plays the Ballades, in addition to having the required technical ability, is also able to understand in more depth the content of these Ballades and the ideas they are meant to express.

Diss. (sammanfattning) Uppsala : Univ., 2001. / Härtill 4 uppsatser.

Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1994. / Vita. Abstract. Includes bibliographical references (leaves 39-45). Also available via the Internet.

Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1992. / Vita. Abstract. Includes bibliographical references (leaves 43-46). Also available via the Internet.

Thesis (Ph. D.)--University of Washington, 2002. / Vita. Includes bibliographical references (leaves 176-185).

Dans le cadre de cette thèse nous nous sommes intéressés à l’amélioration de la qualité visuelle des images, en rehaussant le contraste des images. Nous avons proposé, tout d’abord, une méthode de rehaussement simple et efficace s’inspirant du système visuel humain. Cette méthode est efficace,quand elle est appliquée aux images naturelles en couleur, ou monochromes. La méthode proposée est ensuite améliorée pour pouvoir rehausser d’autre type d’image comme les images médicale, telles que les images de rétine et l’endoscopie. Par la suite, nous nous sommes aussi intéressés aux rehaussements des images médicales et en particulier aux images de mammographie et nous avons donc proposé une méthode de rehaussement de contraste qui leur est spécifiquement dédiée. Au final,nous nous sommes intéressés à l’évaluation des méthodes de rehaussement proposées et aux différentes approches existantes dans la littérature. La méthode d’évaluation proposée s’appuie sur l’analyse radiale et angulaire du spectre d’énergie de Fourier. La validation de notre méthode de rehaussement de contraste a été faite en utilisant des échantillons d’images de 2 bases et en utilisant un test subjectif pour la comparer à d’autres méthodes de rehaussement. La note subjective finale de MOS, obtenue par la moyenne des notes des observateurs, montre la fiabilité de notre méthode de rehaussement de contraste et son intérêt par comparaison aux autres méthodes classiques. / The aim of this thesis is to propose new methods for image enhancement based on oriented and multi-scale transforms using some perceptual criteria. The first part of the thesis is devoted to the development of a simple and efficient contrast enhancement method inspired from the human visual system. This method is evaluated on a set of natural color and monochrome images. The obtained results are evaluated subjectively and by using objective measures based on energy spectrum analysis and perceptual criteria. The enhancement technique is also extended to some medical images, such as mammography and endoscopy images. A special contrast enhancement method adapted to mammography is then proposed. It is based on a segmentation process using a priori information on the mammography images. The last part of the thesis is devoted to image enhancement evaluation. A critical literature survey of image enhancement evaluation methods is provided. The evaluation method proposed in this thesis is based on the radial and angular analysis of the Fourier powerspectrum. Another perceptual approach is proposed to evaluate the output. This method is based on the analysis of the visibility map computed by using a pyramidal contrast. The evaluation is performed on some samples taken from two databases. Both subjective and objective evaluations demonstrate the efficiency of the proposed image enhancement methods.

archives@tulane.edu / 1 / Genevieve Mattei

The dialogue between old and new architecture is a conversation brought to the forefront of the conservationist movement and city planning efforts as cities expand to their physical limits and eco-friendly reuse options become mainstream. As designers try and achieve a mutual respect between existing buildings and modern interventions, we are often faced with the dilemma of not only deciding which architectural artifacts should remain but also how to compose the different historic and modern layers in a way that formulates a new and more dynamic whole as a result of the interaction. The following thesis is an adaptive reuse project of a historically and architecturally significant, turn of the century firehouse located in northwest Washington, DC. This architectural endeavor seeks to find a mutually respectful balance between old and new architecture while highlighting the clear differences in building materials, design aesthetic, and construction methods. / Master of Architecture