Target size and displacement along the axis of implied gravitational attraction: Effects of implied weight and evidence of representational gravity.

Author(s):  
Timothy L. Hubbard
1979 ◽  
Vol 44 ◽  
pp. 41-47
Author(s):  
Donald A. Landman

This paper describes some recent results of our quiescent prominence spectrometry program at the Mees Solar Observatory on Haleakala. The observations were made with the 25 cm coronagraph/coudé spectrograph system using a silicon vidicon detector. This detector consists of 500 contiguous channels covering approximately 6 or 80 Å, depending on the grating used. The instrument is interfaced to the Observatory’s PDP 11/45 computer system, and has the important advantages of wide spectral response, linearity and signal-averaging with real-time display. Its principal drawback is the relatively small target size. For the present work, the aperture was about 3″ × 5″. Absolute intensity calibrations were made by measuring quiet regions near sun center.


2016 ◽  
Vol 14 (1) ◽  
pp. 125-135
Author(s):  
Patrick J. Connolly

In a recent article Fred Ablondi compares the different approaches to occasionalism put forward by two eighteenth-century Newtonians, Colin Maclaurin and Andrew Baxter. The goal of this short essay is to respond to Ablondi by clarifying some key features of Maclaurin's views on occasionalism and the cause of gravitational attraction. In particular, I explore Maclaurin's matter theory, his views on the explanatory limits of mechanism, and his appeals to the authority of Newton. This leads to a clearer picture of the way in which Maclaurin understood gravitational attraction and the workings of nature.


Survey Review ◽  
1994 ◽  
Vol 32 (251) ◽  
pp. 273-278
Author(s):  
A. C. Ruffhead

2021 ◽  
pp. 174702182110248
Author(s):  
Xiaogang Wu ◽  
Aijun Wang ◽  
Ming Zhang

The normalization model of attention (NMoA) predicts that the attention gain pattern is mediated by changes in the size of the attentional field and stimuli. However, existing studies have not measured gain patterns when the relative sizes of stimuli are changed. To investigate the NMoA, the present study manipulated the attentional field size, namely, the exogenous cue size. Moreover, we assessed whether the relative rather than the absolute size of the attentional field matters, either by holding the target size constant and changing the cue size (experiments 1-3) or by holding the cue size constant and changing the target size (experiment 4), in a spatial cueing paradigm of psychophysical procedures. The results show that the gain modulations changed from response gain to contrast gain when the precue size changed from small to large relative to the target size (experiments 1-3). Moreover, when the target size was once again made larger than the precue size, there was still a change in response gain (experiment 4). These results suggest that the size of exogenous cues plays an important role in adjusting the attentional field and that relative changes rather than absolute changes to exogenous cue size determine gain modulation. These results are consistent with the prediction of the NMoA and provide novel insights into gain modulations of visual selective attention.


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