An atmospheric dust recorder     

Willis G. Hazard 《Journal of The Franklin Institute》1934,217(5):571-590

An apparatus is described for recording general atmospheric dust. The full-scale range of the present model of approximately 120 × 10⁶ particles per cubic foot of air may be increased or decreased as desired. The dust concentrations measured are far below smoke concentrations. The method is to impinge dust on a slowly moving strip of transparent film, and to measure the deposit by a comparison of two beams of light, one passing through the dusty film, the other through clean film. The decrease in transmitted light due to the dust is balanced automatically by a motor-driven optical wedge in the unobstructed beam. The position of this wedge is recorded on a chart. Dusty air is sampled continuously for long periods. Rapid fluctuations of a few minutes in length are registered. In this, and in the fact that it is direct-reading, without tedious laboratory quantitation, the recorder offers distinct advantages over the present dust determinators, almost all of which take momentary samples. A different calibration is needed for different dusts. The machine may be adapted to laboratory or field use. In factories, auxiliary blowers may be operated through relays, when the dustiness exceeds a specified level.  相似文献   

Photoelectric and thermionic emission from composite surfaces     

Wayne B. Nottingham 《Journal of The Franklin Institute》1932,214(5):605-606

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The Sins of Methodology     

Martin Willis 《Metascience》2008,17(3):507-510

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Learning Outcome Testing Program: Standardized Classroom Testing in West Virginia Through Item Banking, Test Generation, and Curricular Management Software     

John A. Willis 《Educational Measurement》1990,9(2):11-14

What conditions stimulated the Learning Outcome Testing Program and what approaches were adopted? What issues need to be addressed in the selection of computer software? What steps should be taken to train teachers to develop item banks and use testing software?  相似文献   

Using game‐based learning to support struggling readers at home     

Wayne Holmes 《Learning, Media and Technology》2011,36(1):5-19

Significant numbers of children (6% of 11‐year‐olds) have difficulties learning to read. Meanwhile, children who receive appropriate support from their parents do better in literacy than those who do not. This study uses a case study approach to investigate how digital games designed to support struggling readers in school were used at home, by the parents of six children to support their children’s literacy. Mostly, the children enjoyed playing the games and believe that it helped improve their reading. The parents all valued the opportunity to participate in their child’s learning and believe that the games’ approach to learning is effective. The study considers key influences on the successful use of games to support struggling readers (repetition, feedback, motivation, self‐efficacy, parental beliefs) and raises questions, further consideration of which might usefully inform the future development of effective game‐based learning.  相似文献   

FUTURISM AND EDUCATION     

Willis W. Harman 《Review of Education, Pedagogy & Cultural Studies》2013,35(1):5-17

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English,Si!     

Nina Willis Walter 《College Teaching》2013,61(4):239-240

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“Latino night”: Performances of latino/a culture in northwest Ohio     

Jennifer L. Willis 《Communication quarterly》2013,61(4):335-354

It's something they can relate to. You know, assimilate. They go there, talk in Spanish, not worry about it, drink, have fun, do it all in a language they're accustomed to, or at least with people they feel more comfortable with. I guess that's why a lot of them come Monday nights from these distances. That's what I was trying to explain to Chris. If you have a Latino night it's going to be successful because us as Latinos don't have a lot of options for us to go or places for us to go.  相似文献   

An open letter from the president     

Wayne N. Thompson 《Communication Studies》2013,64(1):2-3

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A comparison of subjective and objective measures of physical exertion     

Skatrud-Mickelson M  Benson J  Hannon JC  Askew EW 《Journal of sports sciences》2011,29(15):1635-1644

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