23,356 research outputs found
Letter from Hattie Allen Ray to John Muir, 1910 Jan 13.
No full text[1]2146 San Antonio AveAlameda, Cal.,Jan. 13, 1910.Dear Mr. Muir,-Ever since Christmas I have been intending to write you and among other things wish you a happy New Year from the Ray family.Allen had a present of a little book which is very dear to his heart. Jessie sent it to him from Honolulu & it is Stickeen by John Muir Allen read it aloud to me and we both enjoyed it hugely. It was queer to hear04681https://scholarlycommons.pacific.edu/jmcl/32024/thumbnail.jp
Ray Allen
No full textArthur Raymond (Ray) Allen is pictured his school year at Roosevelt Elementary. He is the son of Arthur R. and Mabel Allen. He served in the Army. He was born October 29, 1935 and died September 13, 1973
Allen Teel's Graduate Recital
No full textOriginal Format: CassetteComposers in the first graduate recital: Stanley Leonard; David Steinquest; Osvaldo Lacerda; Ruud Wiener; John Serry, Jr.Composers in the second graduate recital: Thomas Wubbenhorst; Paul Smadbeck; William Cahn; J. S. Bach; Robert KreutzFirst Recital: PercussionSecond Recital: Percussio
[Letter from Alex Bradford to Lieutenant and Mrs. Ray Starner - November 4, 1940]
No full textLetter from Alex Bradford to Lieutenant and Mrs. Ray Starner describing the the current state of affairs that the author was experiencing, including: the London blitz, the moral of the troops on the ground, and the collective company of men opposing the Nazi regime
Metamaterials for light rays: ray optics without wave-optical analog in the ray-optics limit
No full textVolumes of sub-wavelength electromagnetic elements can act like homogeneous materials: metamaterials. In analogy, sheets of optical elements such as prisms can act ray-optically like homogeneous sheet materials. In this sense, such sheets can be considered to be metamaterials for light rays (METATOYs). METATOYs realize new and unusual transformations of the directions of transmitted light rays. We study here, in the ray-optics and scalar-wave limits, the wave-optical analog of such transformations, and we show that such an analog does not always exist. Perhaps, this is the reason why many of the ray-optical possibilities offered by METATOYs have never before been considered
Robert Allen Porter and Ray Stewart
No full textRobert Porter Allen (right) pose near the Sass River in the Northwest Territories, Canada.https://digitalcommons.usf.edu/rpa_photographs/1171/thumbnail.jp
The student's guide to completing an author study
No full textThe 'Student's guide to completing an author study' emerged during the early development of the school library resource center program at Glen Stewart Elementary School in Stratford Canada on Prince Edward Island. This research process centered on an author study, with direct teaching and clear assignment. The resulting model has been adapted to various grade levels and subject areas in different schools.Source type: Electronic(1)http://proquest.umi.com/pqdweb?did=49237063&Fmt=7&clientId=65345&RQT=309&VName=PQ
Active X-ray optics for the next generation of X-ray space telescopes
No full textDescribed within is the design, manufacture, metrology and X-ray testing of an active X-ray
prototype intended for the next generation of X-ray telescopes. One of the challenges faced by
the X-ray telescope community is how to combine high resolution and high sensitivity into one
system, as weight limitations place constraints on the optics that can be launched. Therefore the
mandate of the active X-ray prototype is to provide high sensitivity through the ability of the optics
to be nested and to deliver high angular resolution through the active control of the optic’s form.
Piezoelectric unimorph actuators provide the active component: it is intended that they will correct
for figure errors within the optic and therefore increase the angular resolution capability.
The prototype’s design is based upon an ellipsoidal segment which provides point-to-point
focussing of an X-ray source. The prototype itself is composed of an electroformed nickel optic
where the non-reflective surface is populated with 30 piezoelectric actuators and it is the production
of the prototype that is the core of the presented research. Metrology of the actuators’ influence
functions is presented and highlight the prototype’s ability to deform its optic surface by microns.
In addition, the measured influence functions are compared against finite element models and a
distinct similarity between the functions is observed.
The prototype was tested at an X-ray beamline facility in November 2008 and the results
showed the prototype’s ability to correct the optic to achieve an improved angular resolution: from
0.786 arc-minutes to 0.686 arc-minutes in terms of full width half maximum. Finally, difficulties
in the manufacture of the prototype and X-ray testing shall be presented alongside future work in
conclusion to this thesis
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Economies of Size and the Future of Black Farmers
No full textThis paper attempts to assess the options available to blacks in agriculture by examining the existence of economies
of size in agricultural production and the importance of these economies in (a) explaining the past declines and (b) in
predicting the future survival of small farmers in general and black farmers in particular. (It should be remembered that the
problems faced by small farmers apply to. most black farmers. In 1969, only two percent of Southern nonwhite farmers had sales of $20,000 or more.) There are two essential questions that must be answered: (1) Are there economies of size which place small
operators in a disadvantaged position and (2) Are the problems of black farmers more severe than those faced by small farmers
in general because of race.Southern Regional CouncilRay Marshall Center for the Study of Human Resource
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