Generation of high-resolution surface temperature distributions

We have performed numerical calculations to study the generation of arbitrary temperature profiles with high spatial resolution on the surface of a solid. The characteristics of steady-state distributions and time-dependent heating and cooling cycles are examined, as well as their dependence on material properties and device geometry. Ideally, low-power consumption and fast response times are desirable. The simulations show that the achievable spatial resolution is on the order of the substrate thickness and that the response time t+ depends on the width of the individual heating elements. Moreover, the rise time t+ can be significantly shortened by deposition of a thermal insulation layer, which also reduces the power consumption and increases lateral resolution

Physical mechanisms governing pattern fidelity in microscale offset printing

We have studied the offset printing of liquid polymers curable by exposure to ultraviolet light onto flat and unpatterned silicon and glass substrates. The interplay of capillary, viscous, and adhesion forces dominates the dynamics of ink transfer at small feature sizes and low capillary number. For smooth and nonporous substrates, pattern fidelity can be compromised because the ink contact lines are free to migrate across the substrate during plate separation. Using a combination of experiments and equilibrium simulations, we have identified the physical mechanisms controlling ink transfer and pattern fidelity. In considering the resolution limit of this technique, it appears that the dynamics of ink flow and redistribution during transfer do not explicitly depend on the absolute feature size, but only on the aspect ratio of film thickness to feature size. Direct printing holds promise as a high-throughput fabrication method for large area electronics

Zur Nützlichkeit des Morphem-Begriffes in der Deutschlehrerausbildung (DaF)

Im vorliegenden Artikel werden Gründe gegen die Verwendung des Begriffs „Morphem“ in Einführungskursen in die Linguistik angeführt, die im Rahmen von Lehramtsstudiengängen im Fach „Deutsch“ im nichtdeutschsprachigen Ausland durchgeführt werden. Die hauptsächlichen Gründe sind: (a) notorische Schwierigkeiten bei der Anwendung von morphembasierten Analysen auf deutsches Sprachmaterial (z. B. beim „Ablaut“), (b) Entwicklungen innerhalb der Linguistik der letzten 40 Jahre, die die strukturalistischen, morphembasierten Ansätze aus ihrer früheren Führungsposition verdrängt haben, (c) fehlende Relevanz des Begriffes für die Benutzung von Standardwerken und Handbüchern des DaF-Unterrichts. Statt „Morphem“ wird die Verwendung theoretisch neutraler Begriffe wie „Stamm“ oder „Affix“ empfohlen.V článku jsou uvedeny argumenty proti používání pojmu „morfém“ v úvodních seminářích určených studentům německého jazyka v učitelských studijních programech. Hlavními důvody proti používání tohoto pojmu jsou (a) známé potíže při aplikaci na konkrétní jazykový materiál, zejména když jde o němčinu, (b) vývoj lingvistiky v posledních 40 letech, který vedl k tomu, že strukturalistický přístup operující s pojmem „morfém“ pozbyl svého vedoucího postavení v jazykovědě, (c) absence pojmu „morfém“ ve většině příruček a učebnic používaných pro praktické účely ve výuce němčiny jako cizího jazyka. V článku se doporučuje nahradit pojem „morfém“ teoreticky neutrálními pojmy jako „kmen“ nebo „přípona“.The article argues against the use of the concept “morpheme” in introductory classes to linguistics aimed at students of German as a foreign language within teaching degree programs. The use of more neutral terminology as “affix” or “stem” is recommended. The main reasons for the suggestion are (a) notorious problems in applying morpheme-based systems to German morphology (e.g. “Ablaut”), (b) developments inside linguistics within the last 40 years, which led to a loss of significance of the morpheme-based approach to language, (c) irrelevance of the concept for using reference grammars and handbooks in the field of German as a foreign language

Chomsky and Postal on Raising – peripetie s jedním konstrukčním typem

Otázka, jak správně analyzovat konstrukce akuzativu s infinitivem, se stala na konci 60. let jedním z bodů, kvůli kterým došlo k roztržce mezi generativismem hlavního (tj. Chomskyanského) proudu a skupinou generativních sémantiků kolem P. Postela. Zatímco Postal tvrdil, že akuzativní složka ve zmíněné konstrukci je hloubkovým subjektem zanořeného infinitivu, který se v důsledku operace „vyzdvižení subjektu“ ocitne v pozici povrchového objektu, Chomsky hájil názor, že akuzativní složka se nachází i na rovině povrchové struktury v subjektové pozici zanořeného infinitivu, kde jí matricové sloveso takřka „výjimečně“ přiděluje akuzativní pád. Jak je známo, posléze se obecně prosadilo pojetí Chomského. Na této situaci se nic nezměnilo v průběhu dalších třiceti let, až se náhle, „bez dalšího komentáře“ (Seuren 2004, 202n.), objevila v programatickém spisu minimalistického programu (Chomsky 1995) poznámka, že příslušné případy jsou nyní analyzovány jako vyzdvižení nominální fráze do specifikátoru fráze objektové shody (s. 174), tj. do syntaktické pozice vyhrazené pro objekt. Stejná poznámka se opakuje i v článku Chomského (2013, 47) v časopise Lingua. V referátu znovu projdu argumenty, které byly předneseny jednotlivými protagonisty sporu pro to které řešení, a zkusím vyjasnit, zda lze mluvit o zásadním obratu Chomského názoru na danou otázku.The question what the correct analysis of constructions containing an infinitive verb and a nominal constituent in the accusative case would look like became in the 60th one of the stumbling blocks leading to the disassociation of the generative semantics movement (with P. Postal as one of its leading figures) from mainstream, i. e. Chomskyan, generative grammar. Against Postal’s view that the accusative constituent is located in object position at surface structure, Chomsky’s view of the accusative constituent as surface subject exceptionally marked for accusative case remained dominant during the 70th and 80th until suddenly, without further comments (Seuren, 2004), the notion of ECM as raising-to-object appears in the second part of the Minimalist Program (Chomsky 1995). The same analysis is restated in Chomsky (2013, 47). The question suggests itself if we face a major change in Chomsky’s views on the described type of construction or if there is a mere readjustment caused by a change in the theoretical perspective. In the talk I review the well known arguments of both sides of the debate and try to find an answer to the indicated question

The Habitus of Mackenzie King: Canadian Artists, Cultural Capital and the Struggle for Power

This dissertation analyzes the struggle between William Lyon Mackenzie King, Canada’s longest-serving Prime Minister (1922-1930, 1935-1948), and Canadian artists to define and determine the nature and distribution of arts and culture in Canada prior to the 1949 Royal Commission on National Development in the Arts, Letters and Sciences. Using Pierre Bourdieu’s theories of habitus, “fields” of knowledge and power, and religious, social and cultural capital, the dissertation analyzes the central paradox of why—despite his decades-long involvement in half-a-dozen artistic disciplines—King failed to implement cultural policies as Prime Minister that would have benefited Canadian artists and the arts and culture in Canada. The dissertation applies Pierre Bourdieu’s model of social change in which “priests” with conservation strategies and charismatic “prophets” with subversion strategies compete among the “laity” for consumers of their respective symbolic goods to document how artists organized locally and nationally to accumulate social, cultural and political capital in their attempt to compel the federal government to implement their cultural objectives—state support for the arts. The dissertation posits that Mackenzie King’s inability to control his sexual impulses led him to espouse a conception of art whose primary function was to project Christian character and ideals. By establishing King’s religious and sexual habiti, I am able to show why he felt compelled to project such an idealized characterization in works of art depicting himself, members of his family, and public figures whose service to the nation he felt should be emulated by Canadians. As Leader of the Liberal Party, Leader of the Opposition in Parliament and as Prime Minister, King was able to use his political and economic power in the political field over three decades (1919-1948) to define who was a real artist and who was not, what constituted artistic legitimacy and what was the artistic and economic value of Canadian cultural production. The dissertation suggests that the analysis of King’s relationship with the arts and artists provides the key to unlocking the enigma of Mackenzie King and that in the struggle between artists and the Prime Minister over the nature and distribution of arts and culture in Canada, the artists won

Morphology of liquid microstructures on chemically patterned surfaces

We study the equilibrium conformations of liquid microstructures on flat but chemically heterogeneous substrates using energy minimization computations. The surface patterns, which establish regions of different surface energy, induce deformations of the liquid–solid contact line. Depending on the geometry, these deformations either promote or impede capillary breakup and bulge formation. The contact angles of the liquid on the hydrophilic and hydrophobic regions, as well as the pattern geometry and volume of liquid deposited, strongly affect the equilibrium shapes. Moreover, due to the small scale of the liquid features, the presence of chemical or topological surface defects significantly influence the final liquid shapes. Preliminary experiments with arrays of parallel hydrophilic strips produce shapes resembling the simulated forms. These encouraging results provide a basis for the development of high resolution lithography by direct wet printing

Effect of contact angle hysteresis on thermocapillary droplet actuation

Open microfluidic devices based on actuation techniques such as electrowetting, dielectrophoresis, or thermocapillary stresses require controlled motion of small liquid droplets on the surface of glass or silicon substrates. In this article we explore the physical mechanisms affecting thermocapillary migration of droplets generated by surface temperature gradients on the supporting substrate. Using a combination of experiment and modeling, we investigate the behavior of the threshold force required for droplet mobilization and the speed after depinning as a function of the droplet size, the applied thermal gradient and the liquid material parameters. The experimental results are well described by a hydrodynamic model based on earlier work by Ford and Nadim. The model describes the steady motion of a two-dimensional droplet driven by thermocapillary stresses including contact angle hysteresis. The results of this study highlight the critical role of chemical or mechanical hysteresis and the need to reduce this retentive force for minimizing power requirements in microfluidic devices