200,934 research outputs found
An improved thick-film piezoelectric material by powder blending and enhanced processing parameters
No full textThis paper details improvements of the d33 coefficient for thick-film lead zirconate titanate (PZT) layers. In particular, the effect of blending ball and attritor milled powders has been investigated. Mathematical modeling of the film structure has produced initial experimental values for powder combination percentages. A range of paste formulations between 8:1 and 2:1 ball to attritor milled PZT powders by weight have been mixed into a screen-printable paste. Each paste contains 10% by weight of lead borosilicate glass and an appropriate quantity of solvent to formulate a screen printable thixotropic paste. A d33 of 63.5 pC/N was obtained with a combination of 4:1 ball milled to attritor milled powder by weight. The improved paste combines the high d33 values of ball and the consistency of attritor milled powder. The measured d33 coefficient was further improved to 131 pC/N by increasing the furnace firing pro-file to 100
Performance of a micro-engineered ultrasonic particle manipulator
No full textAn ultrasonic microfluidic particle manipulator has been modeled and its experimentally measured separation performance has been compared with the modeled results for 1 µm latex particles, and yeast particles in water
Experimental investigation into the effect of substrate clamping on the piezoelectric behaviour of thick-film PZT elements
No full textThis paper details an experimental investigation of the clamping effect associated with thick-film piezoelectric elements printed on a substrate. The clamping effect reduces the measured piezoelectric coefficient, d33, of the film. This reduction is due to the influence of the d31 component in the film when a deformation of the structure occurs, by either the direct or indirect piezoelectric effect. Theoretical analysis shows a reduction in the measured d33 of 62%, i.e. a standard bulk lead zirconate titanate (PZT)-5H sample with a manufacturer specified d33 of 593pC/N would fall to 227.8pC/N. To confirm this effect, the d33 coefficients of five thin bulk PZT-5H samples of 220µm thickness were measured before and after their attachment to a metallized 96% alumina substrate. The experimental results show a reduction in d33 of 74% from 529pC/N to 139pC/N. The theoretical analysis was then applied to existing University of Southampton thick-film devices. It is estimated that the measured d33 value of 131pC/N of the thick-film devices is the equivalent of an unconstrained d33 of 345pC/N
The workshop as the work: white anti-racism organising in 1960s, 70s, and 80s US social movements
No full textThis thesis explores the rise of anti-racism workshops developed by white activists in various United States social movements from the late 1960s through the mid-1980s. The shifting ideology of the black freedom movement in the late 1960s, from integration to Black Power, transformed white activists‘ place within racial justice struggles. While recent scholarship has begun to turn its attention towards whites‘ ongoing racial justice activities, one of the most radical and widespread of these efforts is consistently overlooked: anti-racism workshops. Increasingly prevalent from the late 1960s through to the diversity-trainings explosion of the 1990s, this thesis demonstrates that these workshops had their roots in the black freedom, women‘s liberation and gay liberation movements. White activists from these movements led these workshops in order to examine white racial domination and privilege within both leftist social movements and larger US society.
Analysing case studies from the black freedom, women‘s liberation and gay liberation/rights movements, this thesis explores the foundational assumptions of anti-racism workshops. It seeks to explain how and why these efforts sought to frame race and racism as issues of knowledge and consciousness and why such efforts constituted radical praxis. It is argued that early anti-racism workshops were pedagogical projects that sought to confront the racial ignorance that structured the lives of whites in the US, including progressives and their liberation movements. This thesis draws attention to the efficacy and power of these workshops in terms of their epistemological effects, in the transformations they brought about in whites‘ understanding, or awareness, of racial realities
[Memo to W. P. Gannaway by R. W. Westphal, November 29, 1963 #1]
No full textCriminal intelligence report addressed to W. P. Gannaway. The report, which was written by R. W. Westphal, states that a white floral cross was ordered to be placed at the grave of Lee Harvey Oswald. The text of the card read: "Deepest sympathy to the family of Lee Harvey Oswald, A Veteran." The original order form is attached to the report
Appropriate Similarity Measures for Author Cocitation Analysis
No full textWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
P. Gould et R. White, Cartes mentales
No full textCrétin Claude. P. Gould et R. White, Cartes mentales. In: Revue de géographie de Lyon, vol. 59, n°1-2, 1984. p. 120
[Report to W. P. Gannaway by J. R. Revill, February 5, 1964 #2]
No full textCriminal intelligence report written by J. R. Revill and submitted to W. P. Gannaway of the Secret Service Bureau. The report states that in preparation for President Kennedy's visit to Dallas, Texas, the Criminal Intelligence Section kept members of extremist groups under surveillance. Active groups in Dallas included (among others) the KKK, the Indignant White Citizens Council, National States Rights Party, and Black Muslims. Members of the Indignant White Citizens Council were seen outside of the Dallas Trade Mart on November 22nd and arrested. These individuals were: Bobby Joiner, Raymond Lee Joiner, Roy Eugene Joiner, Gary Dwayne Joiner, Gene Audra Guinn, and William Lee Cummings
[Report to W. P. Gannaway by J. R. Revill, February 5, 1964 #1]
No full textCriminal intelligence report written by J. R. Revill and submitted to W. P. Gannaway of the Secret Service Bureau. The report states that in preparation for President Kennedy's visit to Dallas, Texas, the Criminal Intelligence Section kept members of extremist groups under surveillance. Active groups in Dallas included (among others) the KKK, the Indignant White Citizens Council, National States Rights Party, and Black Muslims. Members of the Indignant White Citizens Council were seen outside of the Dallas Trade Mart on November 22nd and arrested. These individuals were: Bobby Joiner, Raymond Lee Joiner, Roy Eugene Joiner, Gary Dwayne Joiner, Gene Audra Guinn, and William Lee Cummings
P. Gould et R. White, Cartes Mentales
No full textScariati Renato. P. Gould et R. White, Cartes Mentales. In: Le Globe. Revue genevoise de géographie, tome 124, 1984. pp. 117-118
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