For users away from the office or home, there is an increasing demand for mobile solutions that offer effective collaborative facilities on the move. The mobile cellular device, or “smart phone”, can offer a ubiquitous platform to deliver such services, provided that its many physical and technological constraints can be overcome. In an effort to better support mobile collaboration, this thesis presents a contributing Mobile Exchange Architecture (MEA) designed to improve upon the capabilities provided by mobile devices to enable synchronous exchange of digital media during a phone conversation using wireless networks and cellular devices. This research includes the design and development of one such MEA in the form of a fully functional Photo-conferencing service, supporting shared remote interaction techniques, simultaneous voice communication and seamless digital media exchange between remote and collocated mobile users. Furthermore, through systematic design, experimental evaluations and field studies we evaluate the effects of different shared remote interaction techniques – 'pointing', 'scaling', 'mixed' and 'hybrid' – assessing the task effort required by users when interacting around shared images across resource constrained mobile devices. This thesis presents a direction for the future development of technologies and methods to enable a new era of scalable always-to-hand mobile collaborative environments.

Abstract Reform, liberalization, and economic takeoff have propelled China toward becoming a major world power. Media industrialization and market orientation, combined with the growing pace of conglomeratization and globalization, are now an important national strategy for Beijing. One of its objectives is to gain a dominant voice in the international community while holding its own against leading European and American transnational media that are already eyeing China¡¦s media industry. Another objective is to suppress Taiwan¡¦s voice in the world arena and gradually marginalize Taiwan¡¦s film and television industries in the ethnic Chinese community. Even while the two sides of the Taiwan Strait are actively engaged in cultural and media exchanges, Taiwan has experienced a slowdown as China picks up pace in audiovisual media development. Taiwanese businesses and performing artists have been forced to take a strategic approach in seeking a future in China¡¦s market. This has resulted in an outflow of capital, human resources, and technology that has hurt Taiwan¡¦s film and television industries. China, on its part, has strategically ¡§attracted funding while keeping out programs¡¨ through media exchange policies and legal restrictions. It has blocked the broadcast of Taiwanese TV productions on local channels as well as the reception of Taiwan¡¦s TV channels. Additionally, it has used its huge market potential as bait to lure Taiwanese performing artists and media professionals to seek commercial and performing opportunities on the other side of the Strait. Through this two-pronged approach, China is trying to establish cultural hegemony over Taiwan with its media exports while pushing for unification. In other words, China¡¦s rapidly expanding audiovisual industry and the platform for cross-strait media exchange have contributed to the dwindling of Taiwan¡¦s film and television industries. China¡¦s carrot-and-stick strategy has compelled Taiwanese artists to cooperate and openly express views on specific political and national identity issues, thereby influencing viewers and listeners in Taiwan. This thesis explores how China¡¦s swiftly growing media industry has marginalized Taiwan¡¦s audiovisual media and influenced the national identity concept of Taiwanese performing artists. For this purpose, historical records and documents are analyzed and in-depth interviews conducted. The thesis takes an interdisciplinary approach that incorporates the concept of cultural hegemony espoused by Antonio Gramsci, the theory of culture industry advocated by Anthony Giddens and Nicholas Garnham, the role of discourse proposed by Michel Foucault, and the concept of national identity expounded by Benedict Anderson and Jhang Mao-guei. Research findings indicate a large gap between publicly expressed views and genuine standpoints of Taiwanese performing artists. Their positions on national identity clearly reflect a complex effect resulting from indelible impressions of Taiwan¡¦s history, education under the 50-year rule by the Kuomintang, Taiwan¡¦s democratic achievements, and realization that China adopts a very different social system. The study has not found a perceptible change in the national identity concept of Taiwanese artists seeking a future on the western shore of the Strait. Nonetheless, should cross-strait media exchange expand and Taiwan¡¦s film and television industries continue to weaken, Taiwanese artists will ultimately seek a sustainable future in China. Sooner or later, they will identify with China and embrace Beijing¡¦s ideological stand on cross-strait unification. Keywords: cultural hegemony culture industry conglomeratization media exchange, audiovisual exchange exposition national identity

The nematode Caenorhabditis elegans is a model organism for understanding sensory molecules of multicellular organisms. Ovulating hermaphrodites produce putative pheromone(s) that cause male attraction. Because pheromones are produced in such small quantities, adult conditioned-media from large-scale synchronous culture is necessary to analyze these pheromones. Current protocols for culture synchronization have volume constraints that limit large-scale synchronous cultures and current methodology for adult conditioned-media production is impractical. Modification of Tangential Flow Filtration (TFF) systems was investigated for use as a method to increase the volume limits of bleach egg harvest for C. elegans culture synchronization. Also, an adult retention device built within the culture vessel was investigated to optimize the environment for aseptic conditioned-media production from dense large-scale C. elegans cultures. During this investigation, we have shown that synchronous C. elegans cultures for adult conditioned-media production can be grown at scales larger than reported before, with potential for further scale up. Our growth methodologies have also yielded denser cultures than previously achieved at large scales. Since rapid bleach harvesting appears to be the bottleneck for large-scale production of synchronous C. elegans cultures, our approach of using modified TFF systems with mesh to retain C. elegans eggs increased the amount of eggs that could be bleach harvested at one time. Using this method we have been able to achieve up to 5x103 synchronous C. elegans per mL at a 50L scale. Since scale-up of TFF is straightforward, our results suggest that the technique reported here can easily be applied to larger scale systems for production of adult conditionedmedia from C. elegans. Further, the adult retention device within the culture vessel can ensure that the whole process remains aseptic.

In both, cell secretome analysis and bacteria evolution, controlled handling of particles with a few to sub-micrometers in size and media exchange are inevitable in order to investigate body fluid’s proteins or change the surrounding culture conditions for pivoted evolution. Typically, nanofiltration and ultra-centrifugation are employed which can lead to cell damage, need large sample volumes and have a high sample loss. Using contactless and label-free acoustic cell manipulation, disadvantages of other magnetic, dielectric or hydrodynamic methods can be avoided. Here, a novel design using acoustic forces for small particle trapping and media exchange is thoroughly numerically investigated including first- and second-order acoustic effects. The device comprises parallel aligned medium and air channels separated by a thin wall. Particle trapping occurs at this thin wall. The medium channel dimensions (height and width) and thin wall thickness are optimized with respect to trapping forces. Thinnest walls are preferable and an aspect ratio of 0.8. First preliminary experimental variation with polystyrene particles showed good agreement with the simulations. Thereby the particle trapping efficiency is evaluated under quiescent flow conditions. For particle trapping, a device with a channel height of 290μm and an aspect ratio of 0.7 is superior which supports the numerical results. Finally, medium exchange of E. coli bacteria is demonstrated with best results for a device with a channel height of 450μm and an aspect ratio of 0.8 showing that 13.4% of the initial bacteria were released after medium exchange which can be used for further processing.

Chemically ordered FePt is one of the most promising materials to reach the ultimate limitations in storage density of future magnetic recording devices due to its high uniaxial magnetocrystalline anisotropy and a corrosion resistance superior to rare-earth based magnets. In this study, FePt and FePt/Cu bilayers have been sputter deposited at room temperature onto thermally oxidized silicon wafers, glass substrates and self-assembled arrays of spherical SiO2 particles with diameters down to 10 nm. Millisecond flash lamp annealing, as well as conventional rapid thermal annealing was employed to induce the phase transformation from the chemically disordered A1 phase into the chemically ordered L10 phase. The influence of the annealing temperature, annealing time and the film thickness on the ordering transformation and (001) texture evolution of FePt films with near equiatomic composition was studied. Whereas flash lamp annealed FePt films exhibit a polycrystalline morphology with high chemical L10 order, rapid thermal annealing can lead to the formation of chemically ordered FePt fifilms with (001) texture on amorphous SiO2/Si substrates. The resultant high perpendicular magnetic anisotropy and large coercivities up to 40 kOe are demonstrated. Simultaneuosly to the ordering transformation, rapid thermal annealing to temperatures exceeding 600 °C leads to a break up of the continuous FePt film into separated islands. This dewetting behavior was utilized to create regular arrays of FePt nanostructures on SiO2 particle templates with periods down to 50 nm. The addition of Cu improves the (001) texture formation and chemcial ordering for annealing temperatures T < 600 °C. In addition, the magnetic anisotropy and the coercivity of the ternary FePtCu alloy can be effectively tailored by adjusting the Cu content. The prospects of FePtCu based exchange spring media, as well as the magnetic properties of FePtCu nanostructures fabricated using e-beam and nanoimprint lithography have been investigated.