Two detection cum latency models are constructed by combining sets of plausible assumptions about latency with, in the first instance, the model of the Theory of Signal Detection and, in the second instance, a general threshold model. The aim of this paper is to show that latency statistics can be used to provide sharp tests for distinguishing between the two models. The two statistics studied ...

We measured the lowest velocity (velocity threshold) for discriminating motion direction in relative and uniform motion stimuli, varying the contrast and the spatial frequency of the stimulus gratings. The results showed significant differences in the effects of contrast and spatial frequency on the threshold, as well as on the absolute threshold level between the two motion conditions, except ...

The dependence of spatial frequency on accommodation has been investigated extensively. Recently, differences between myopes and emmetropes with respect to accommodative microfluctuations for high spatial frequency targets have been reported. Considering the diversity of accommodative responses (ARs) to sinusoidal gratings among subjects, this experiment was designed to analyze the contrast dep...

Simultaneous Contrast and Assimilation test targets are almost always viewed at high light levels. We measured the appearances of Simultaneous Contrast, Assimilation and other spatial surrounds near absolute rod threshold. Given the very different spatial organizations of receptive fields in rod and cone vision at detection threshold, it is not obvious that these familiar cone-vision spatial ef...

Spatial coupling of individual LDPC codes improves the BP threshold of the coupled ensemble to the MAP threshold of the underlying ensemble. In this report, we investigate the performance of spatial coupling on LDGM codes which might lead to constructing a new class of rateless codes. In what follows, we study Raptor codes as a class of rateless codes and investigate spatial coupling on LDPC en...

snow cover area is one of the most important criteria to calculate snow melt runoff. this can have an effect on the biology of the plant and the environment of a region. using the catchment basin physical characteristic to calculate snow cover area is a conventional method, though its accuracy is not good enough. most of the useful methods in calculating snow cover area are based on satellite i...

background: our hearing ability in space is critical for hearing speech in noisy environment and localization. the spatial hearing questionnaire (shq) has been devised to focus only on spatial haring tasks (e.g., lateralization, distance detection and binaural detection). the aim of the present study was to determine the reliability and validity of the persian translation of the shq (spatial he...

Studies on spatial co-location mining required distance threshold to define spatial neighbourhood (Shashi Shekhar and Yan Huang(2001); Yoo and Shekhar (2004, 2006); Yasuhiko Morimoto(2001); Koperski and Han(1995); Ding et al. (2008)) However, it is problematical for users to choose suitable threshold values because they lack prior knowledge about spatial data. Spatial neighbourhood has been def...

Usually a high-contrast, co-local mask increases contrast threshold (inhibition). Interestingly, a laterally displaced mask (flanker) can facilitate contrast detection (Vision Research 33 (1993) 993; 34 (1994) 73). When spatial scaling of these flanker effects was implied, stimulus bandwidth was confounded with spatial frequency (lambda(-1)). Under conditions where at lower spatial frequencies,...

In this paper the authors investigate critical phase transition characteristic of collective action by considering the mechanisms of both rational utility and psychological threshold based on the Granovetter (1978)’s threshold model. Numeric simulation is used to observe the collective dynamics with consideration of both spatial factor and social network friendship density. The authors observe ...