Humans can easily segregate texture regions based on differences in contrast, orientation, and contrast polarity. It has been suggested that these abilities can be inclusively modeled by 2nd-order visual mechanisms that detect changes in the half-wave rectified outputs of orientation-selective filters. Using a subthreshold-summation paradigm, however, we show that modulations of contrast polari...

This paper presents the preliminary results of an extensive parametric study on seismic response of two-dimensional semi-sine shaped hills to vertically propagating incident P- and SV-waves. Clear perspectives of the induced diffraction and amplification patterns are given by investigation of time-domain and frequency-domain responses. It is shown that site geometry, wave characteristics , and ...

An assumption commonly made in the study of visual perception is that the lower the contrast threshold for a given stimulus, the more sensitive and selective will be the mechanism that processes it. On the basis of this consideration, we investigated contrast thresholds for two classes of stimuli: sine-wave gratings and radial frequency stimuli (i.e., j0 targets or stimuli modulated by spherica...

this paper presents a modified 32-bit rom-based direct digital frequency synthesizer (ddfs). maximum output frequency of the ddfs is limited by the structure of the accumulator used in the ddfs architecture. the hierarchical pipeline accumulator (hpa) presented in this paper has less propagation delay time rather than the conventional structures. therefore, it results in both higher maximum ope...

Based on the recently introduced fractional Taylor’s formula, a fractional heat conduction constitutive equation is formulated by expanding the single-phase lag model using the fractional Taylor’s formula. Combining with the energy balance equation, the derived fractional heat conduction equation has been shown to be capable of modeling diffusion-to-Thermal wave behavior of heat propagation by ...

The efficiency of the traditional DDFS is greatly depends on the large size of memory. The ROM less architecture for generating sine wave and its necessary corrective measure based on parabola has already been developed. This paper proposes a modified parabola by adding a triangular wave to achieve a sine wave with less distortion. This architecture gives better performance.

This work is focused on the finite element study of the energy absorbing behavior of aluminum (corrugated webs). The aim is to study the mechanism of energy absorption in specific metallic structures by understanding these mechanisms. The sine wave web (or corrugated web) structural component constructed of aluminum has been chosen as the specific structural element for this study. The sine wav...

It is hypothesized that in sine-wave replicas of natural speech, lexical tone recognition would be severely impaired due to the loss of F0 information, but the linguistic information at the sentence level could be retrieved even with limited tone information. Forty-one native Mandarin-Chinese-speaking listeners participated in the experiments. Results showed that sine-wave tone-recognition perf...

In this paper we describe an efficient CORDIC algorithm that completely eliminates the scaling factor. Besides we have proposed an algorithm to redefine the elementary angles for reducing the number of CORDIC iterations. The Coordinate Rotational Digital Computer (CORDIC) algorithm is another classic approach for sine wave generation. The particular architecture hereby presented generates the p...

We investigated the noise levels in cell-attached patch capacitance recordings with a lock-in amplifier. The capacitance noise level decreases with increasing sine wave frequency up to 20-40 kHz. With a 20-mV rms sine wave the rms noise level above 8 kHz is <50 aF. With increasing sine wave amplitudes a further reduction down to 14 aF could be achieved. Capacitance measurements with a lock-in a...