Effects of temporal coherence and signal-frequency uncertainty for tone detection in a random-frequency multi-tonal masker

2017 ◽  
Vol 141 (5) ◽  
pp. 3902-3903
Author(s):  
Emily Buss ◽  
Huanping Dai
Keyword(s):  
Temporal Coherence ◽  
Signal Frequency ◽  
Random Frequency ◽  
Tone Detection

Effects of Signal and Masker Uncertainty on Children’s Detection

1995 ◽  
Vol 38 (2) ◽  
pp. 503-511 ◽  
Author(s):  
Prudence Allen ◽  
Frederic Wightman
Keyword(s):  
Psychometric Function ◽  
Forced Choice ◽  
Preschool Age ◽  
Signal Frequency ◽  
Focused Attention ◽  
Random Frequency ◽  
Random Level

This paper reports the results of two experiments that examined the effects of signal and masker uncertainty on preschool-age children’s and adults’ detection of tonal signals in noise maskers. In Experiment 1 (signal uncertainty) the signal was randomly at 501 or 2818 Hz. The majority of the adult listeners showed a slight decrement in performance consistent with an ability to monitor both frequencies simultaneously. The majority of the children, however, showed no decrement in performance, suggesting that the children may not have focused attention at the signal frequency even when it was fixed. In Experiment 2 (masker uncertainty), random-frequency, random-level, tonal distracters were added to each interval of the 2 alternative-forced-choice (2afc) procedure. The effect of masker uncertainty was much larger than that of signal uncertainty. For most of the adult listeners and some of the children, the distracters produced higher thresholds (on average by 10 dB) and shallower psychometric function slopes. For most of the children, thresholds increased by 20 dB or more and psychometric functions were often nearly flat. This paper reports the results of two experiments that examined the effects of signal and masker uncertainty on preschool-age children's and adults' detection of tonal signals in noise maskers. In Experiment 1 (signal uncertainty) the signal was randomly at 501 or 2818 Hz. The majority of the adult listeners showed a slight decrement in performance consistent with an ability to monitor both frequencies simultaneously. The majority of the children, however, showed no decrement in performance, suggesting that the children may not have focused attention at the signal frequency even when it was fixed. In Experiment 2 (masker uncertainty), random-frequency, random-level, tonal distracters were added to each interval of the 2 alternative-forced-choice (2afc) procedure. The effect of masker uncertainty was much larger than that of signal uncertainty. For most of the adult listeners and some of the children, the distracters produced higher thresholds (on average by 10 dB) and shallower psychometric function slopes. For most of the children, thresholds increased by 20 dB or more and psychometric functions were often nearly flat.

Principle and practice of high-resolution imaging with a field-emission TEM

1992 ◽  
Vol 50 (1) ◽  
pp. 138-139
Author(s):  
Max T. Otten ◽  
Wim M.J. Coene
Keyword(s):  
High Resolution ◽  
Field Emission ◽  
Incidence Angle ◽  
Temporal Coherence ◽  
Energy Spread ◽  
High Resolution Imaging ◽  
Major Improvement ◽  
High Resolution Images ◽  
Resolution Imaging

High-resolution imaging with a LaB6 instrument is limited by the spatial and temporal coherence, with little contrast remaining beyond the point resolution. A Field Emission Gun (FEG) reduces the incidence angle by a factor 5 to 10 and the energy spread by 2 to 3. Since the incidence angle is the dominant limitation for LaB6 the FEG provides a major improvement in contrast transfer, reducing the information limit to roughly one half of the point resolution. The strong improvement, predicted from high-resolution theory, can be seen readily in diffractograms (Fig. 1) and high-resolution images (Fig. 2). Even if the information in the image is limited deliberately to the point resolution by using an objective aperture, the improved contrast transfer close to the point resolution (Fig. 1) is already worthwhile.

Test Circuit Conditioning for Soft Defect Localization

2014 ◽  
Author(s):  
Kristopher D. Staller ◽  
Corey Goodrich
Keyword(s):  
Laser Beam ◽  
Failure Analysis ◽  
Signal Frequency ◽  
Dynamic Failure ◽  
The Third ◽  
Analysis Technique ◽  
Test Circuit ◽  
Defect Localization ◽  
Manual Input ◽  
Fast Dynamic

Abstract Soft Defect Localization (SDL) is a dynamic laser-based failure analysis technique that can detect circuit upsets (or cause a malfunctioning circuit to recover) by generation of localized heat or photons from a rastered laser beam. SDL is the third and seldom used method on the LSM tool. Most failure analysis LSM sessions use the endo-thermic mode (TIVA, XIVA, OBIRCH), followed by the photo-injection mode (LIVA) to isolate most of their failures. SDL is seldom used or attempted, unless there is a unique and obvious failure mode that can benefit from the application. Many failure analysts, with a creative approach to the analysis, can employ SDL. They will benefit by rapidly finding the location of the failure mechanism and forgoing weeks of nodal probing and isolation. This paper will cover circuit signal conditioning to allow for fast dynamic failure isolation using an LSM for laser stimulation. Discussions of several cases will demonstrate how the laser can be employed for triggering across a pass/fail boundary as defined by voltage levels, supply currents, signal frequency, or digital flags. A technique for manual input of the LSM trigger is also discussed.

Energy Absorption in Dielectric–Dispersed Conductor Compositions versus Signal Frequency

2020 ◽  
Vol 65 (6) ◽  
pp. 935-937
Author(s):  
V. A. Sotskov ◽  
O. G. Ashkhotov ◽  
T. T. Magkoev
Keyword(s):  
Energy Absorption ◽  
Signal Frequency

Time

2018 ◽  
Author(s):  
Bruno and
Keyword(s):  
Temporal Coherence ◽  
The Other ◽  
Sensory Receptors ◽  
Traditional Notion ◽  
Physical Energy ◽  
Multisensory Interactions ◽  
The Senses ◽  
Perception Of Time ◽  
Temporal Extent ◽  
Stimulus Time

Within the traditional notion of the senses, the perception of time is especially puzzling. There is no specific physical energy carrying information about time, and hence no sensory receptors can transduce a ‘temporal stimulus.’ Time-related properties of events can instead be shown to emerge from specific perceptual processes involving multisensory interactions. In this chapter, we will examine five such properties: the awareness that two events occur at the same time (simultaneity) or one after the other (succession); the coherent time-stamping of events despite inaccuracies and imprecisions in coding simultaneity and succession (temporal coherence); the awareness of the temporal extent occupied by events (duration); the organization of events in regular temporal units (rhythm).

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