No description available.

No description available.

No description available.

A delay line phase shifter for the 30-70 GHz range is presented that uses an aluminum micro-ribbon array fabricated in the ground plane of a microstrip transmission line. Phase shift is achieved by changing the propagation velocity of an RF signal in the transmission line by controlling the effective permittivity of the substrate. This is done by actuating the micro-ribbons away from the substrate. This phase shifter has the benefits of analog phase shifts and high Figure of Merit. Simulations were done to model the micro-ribbon deflections, transmission line performance and phase shift. Arrays of 5, 10, and 20 μm wide micro-ribbons were fabricated and tested. At 40.80 GHz, the 20 μm wide micro-ribbons had a measured phase shift of 33º with an actuation voltage of 120 V. The corresponding Figure of Merit was a negative value indicating that there was no line loss due to ribbon deflection. / February 2008

A delay line phase shifter for the 30-70 GHz range is presented that uses an aluminum micro-ribbon array fabricated in the ground plane of a microstrip transmission line. Phase shift is achieved by changing the propagation velocity of an RF signal in the transmission line by controlling the effective permittivity of the substrate. This is done by actuating the micro-ribbons away from the substrate. This phase shifter has the benefits of analog phase shifts and high Figure of Merit. Simulations were done to model the micro-ribbon deflections, transmission line performance and phase shift. Arrays of 5, 10, and 20 μm wide micro-ribbons were fabricated and tested. At 40.80 GHz, the 20 μm wide micro-ribbons had a measured phase shift of 33º with an actuation voltage of 120 V. The corresponding Figure of Merit was a negative value indicating that there was no line loss due to ribbon deflection.

A delay line phase shifter for the 30-70 GHz range is presented that uses an aluminum micro-ribbon array fabricated in the ground plane of a microstrip transmission line. Phase shift is achieved by changing the propagation velocity of an RF signal in the transmission line by controlling the effective permittivity of the substrate. This is done by actuating the micro-ribbons away from the substrate. This phase shifter has the benefits of analog phase shifts and high Figure of Merit. Simulations were done to model the micro-ribbon deflections, transmission line performance and phase shift. Arrays of 5, 10, and 20 μm wide micro-ribbons were fabricated and tested. At 40.80 GHz, the 20 μm wide micro-ribbons had a measured phase shift of 33º with an actuation voltage of 120 V. The corresponding Figure of Merit was a negative value indicating that there was no line loss due to ribbon deflection.

No description available.

Intuitively, a ribbon is a topological and geometric surface that has a fixed width. In the 1960s and 1970s, Calugareanu, White, and Fuller each independently proved a relationship between the geometry and topology of thin ribbons. This result has been applied in mathematical biology when analyzing properties of DNA strands. Although ribbons of small width have been studied extensively, it appears as though little to no research has be completed regarding ribbons of large width. In general, suppose K is a smoothly embedded knot in R3. Given an arclength parametrization of K, denoted by gamma(s), and given a smooth, smoothly-closed, unit vector field u(s) with the property that u'(s) is not equal to 0 for any s in the domain, we may define a ribbon of generalized width r0 associated to gamma and u as the set of all points gamma(s) + ru(s) for all s in the domain and for all r in [0,r0]. These wide ribbons are likely to have self-intersections. In this thesis, we analyze how the knot type of the outer ribbon edge relates to that of the original knot K and the embedded resolutions of the unit vector field u as the width increases indefinitely. If the outer ribbon edge is embedded for large widths, we prove that the knot type of the outer ribbon edge is one of only finitely many possibilities. Furthermore, the possible set of finitely many knot types is completely determinable from u, independent of gamma. However, the particular knot type in general depends on gamma. The occurrence of stabilized knot types for large widths is generic; we show that the set of pairs (gamma, u) for which the outer ribbon edge stabilizes for large widths (as a subset of all such pairs (gamma, u) is open and dense in the C1 topology. Finally, we provide an algorithm for constructing a ribbon of constant generalized width between any two given knot types K1 and K2. We conclude by providing concrete examples.

As the commercial business is getting more and more active, along with the living standard of Taiwanese people improved, consumers not only care about the quality of products, but also emphasize the spiritual side they can create. Therefore, packing gifts with ribbons has changed the quality of people¡¦s life and molded their dispositions unobtrusively. There is a saying that ¡§the tailor makes the man¡¨, and it goes the same with gift packing. Besides, gift packing has become a media for an enterprise to sell its products in a more creative way. This study tried to explore the influence of ribbon gift packing on the behavior of consumers through the emphasis on the concept of creativity, uniqueness and refinement. This study utilized E. B. M. consuming behavior model, taking as an independent variable the consuming behavior of the consumers buying gifts packed with ribbons and tacking as dependent variables the demographics variable and the life style variable, and it came up with a research framework and a hypothesis. Besides, the study used purposive selection form the consumers buying gifts packed with ribbons, and the data would be verified through statistical methods. The study found that the factors of the life style of the consumers in Taichung who buy gifts packed with ribbons includes fashion pursuing, independence and confidence, life efficiency, social experience, stereotype, and egoism. Through factor analysis, those consumers are divided into four groups: traditional value group, fashion trend group, highly independent group and experimentalist group. There are noticeable disparities among each group in terms of ages, monthly salary, education levels and vocations. The consumers in each of the groups behave differently on their consuming behaviors. The noticeable differences are shown in need cognition, information searching, evaluation of schemes, purchasing and results. The seller can do some adjustments on the strategy of marketing combinations according to these five factors.

Würzburg, Univ., Diss., 2009. / Zsfassung in engl. Sprache.